Sample records for self-expandable metallic stents

  1. Functional Self-Expandable Metal Stents in Biliary Obstruction

    PubMed Central

    Kwon, Chang-Il; Ko, Kwang Hyun; Hahm, Ki Baik

    2013-01-01

    Biliary stents are widely used not only for palliative treatment of malignant biliary obstruction but also for benign biliary diseases. Each plastic stent or self-expandable metal stent (SEMS) has its own advantages, and a proper stent should be selected carefully for individual condition. To compensate and overcome several drawbacks of SEMS, functional self-expandable metal stent (FSEMS) has been developed with much progress so far. This article looks into the outcomes and defects of each stent type for benign biliary stricture and describes newly introduced FSEMSs according to their functional categories. PMID:24143314

  2. Feasibility of using bulk metallic glass for self-expandable stent applications.

    PubMed

    Praveen Kumar, Gideon; Jafary-Zadeh, Mehdi; Tavakoli, Rouhollah; Cui, Fangsen

    2017-10-01

    Self-expandable stents are widely used to restore blood flow in a diseased artery segment by keeping the artery open after angioplasty. Despite the prevalent use of conventional crystalline metallic alloys, for example, nitinol, to construct self-expandable stents, new biomaterials such as bulk metallic glasses (BMGs) are being actively pursued to improve stent performance. Here, we conducted a series of analyses including finite element analysis and molecular dynamics simulations to investigate the feasibility of using a prototypical Zr-based BMG for self-expandable stent applications. We model stent crimping of several designs for different percutaneous applications. Our results indicate that BMG-based stents with diamond-shaped crowns suffer from severe localization of plastic deformation and abrupt failure during crimping. As a possible solution, we further illustrate that such abrupt failure could be avoided in BMG-based stents without diamond shape crowns. This work would open a new horizon for a quest toward exploiting superior mechanical and functional properties of metallic glasses to design future stents. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1874-1882, 2017. © 2016 Wiley Periodicals, Inc.

  3. Self-Expandable Metal Stents and Trans-stent Light Delivery: Are Metal Stents and Photodynamic Therapy Compatible?

    PubMed Central

    Wang, Luo-Wei; Li, Li-Bo; Li, Zhao-Shen; Chen, Yang K; Hetzel, Fred W.; Huang, Zheng

    2008-01-01

    Background and Objectives: Obstructive non-small cell lung cancer and obstructive esophageal cancer are US FDA approved indications of photodynamic therapy (PDT). The usefulness of PDT for the treatment of cholangiocarcinoma is currently under clinical investigation. Endoscopic stenting for lumen restoration is a common palliative intervention for those indications. It is important to assess whether self-expandable metal stents are compatible with trans-stent PDT light delivery. Study Design/Materials and Methods: Direct effects of various components of metal biliary (n = 2), esophageal (n = 2), and bronchial (n = 1) stents on PDT light transmittance and distribution were examined using a point or linear light source (630 or 652 nm diode laser). Resected pig biliary duct and esophageal wall tissues were used to examine the feasibility of PDT light delivery through the fully expanded metal stents. Results: While using a point light source, the metal components (thread and joint) of the stent could cause a significant shadow effect. The liner material (polytetrafluoroethylene or polyurethane) could cause various degrees of light absorption. When the stent was covered with a thin layer of biliary duct and esophageal tissues containing all wall layers, the shadow effect could be mitigated due to tissue scattering. Conclusions: This study clearly demonstrates that it is feasible to combine stenting and PDT for the treatment of luminal lesions. PDT light dose should be adjusted to counteract the reduction of light transmittance caused by the metal and liner materials of stent. PMID:18951422

  4. Long-term outcome of self expandable metal stents for biliary obstruction in chronic pancreatitis.

    PubMed

    Waldthaler, Alexander; Schütte, Kerstin; Weigt, Jochen; Kropf, Siegfried; Malfertheiner, Peter; Kahl, Stefan

    2013-01-10

    Insertion of a self-expandable metal stent is still controversial for treatment of benign common bile duct stenosis but can be a valuable alternative to surgical treatment. Aim of our study was to analyze the efficacy of covered and uncovered self-expandable metal stent in patients with chronic pancreatitis and common bile duct stenosis. Twenty patients with common bile duct stenosis due to alcoholic chronic pancreatitis were retrospective analyzed. All patients had advanced chronic pancreatitis, presenting with calcifications in pancreatic head. Uncovered self-expandable metal stent (uSEMS) were used in 11 patients (3 females, 8 males) while in 9 patients (3 females, 6 males) partially covered self-expandable metal stent (cSEMS) were inserted. All patients treated with self-expandable metal stent had contraindications for surgery. Overall mean follow up time was 155 weeks: 206 (52-412) weeks in uSEMS, and 93 (25-233) weeks in cSEMS, respectively. Stent patency was in mean 118 weeks: 159 (44-412) weeks in uSEMS and 67 (25-150) weeks in cSEMS (P=0.019). In the uSEMS group, reintervention was necessary in 5 patients (45%) due to stent obstruction, whereas in the cSEMS group 4 patients (44%) needed reintervention (2 obstructions, 2 migration). Stent migration is an early complication, compared to obstruction (P<0.05), and in cSEMS obstruction occurred significantly earlier compared to uSEMS (P<0.05). Patency of uSEMS was significantly longer compared to partially cSEMS. Available self-expandable metal stent, unfortunately, do not meet the demands on successful treatment of benign common bile duct stenosis.

  5. Clinical Outcomes of Self-Expandable Metal Stents for Malignant Rectal Obstruction.

    PubMed

    Lee, Hyun Jung; Hong, Sung Pil; Cheon, Jae Hee; Kim, Tae Il; Kim, Won Ho; Park, Soo Jung

    2018-01-01

    Self-expandable metal stents are widely used to treat malignant colorectal obstruction. However, data on clinical outcomes of stent placement for rectal obstruction specifically are lacking. We aimed to investigate the clinical outcomes of self-expandable metal stents in malignant rectal obstruction in comparison with those in left colonic obstruction and to identify factors associated with clinical failure and complication. This was a retrospective study. The study was conducted at a tertiary care center. Between January 2005 and December 2013, medical charts of patients who underwent stent placement for malignant rectal or left colonic obstruction were reviewed retrospectively. Study intervention included self-expandable metal stent placement. Technical success, clinical success, and complications were measured. Technical success rates for the 2 study groups (rectum vs left colon, 93.5% vs 93.1%; p = 0.86) did not differ significantly; however, the clinical success rate was lower in patients with rectal obstruction (85.4% vs 92.1%; p = 0.02). In addition, the complication rate was higher in patients with rectal obstruction (37.4% vs 25.1%; p = 0.01). Patients with rectal obstruction showed higher rates of obstruction because of extracolonic malignancy (33.8% vs 15.8%; p < 0.001) and stent use for palliation (78.6% vs 56.3%; p < 0.001). Multivariate analysis indicated obstruction attributed to extracolonic malignancy and covered stent usage to be independent risk factors for clinical failure. Factors predictive of complications in the palliative group were total obstruction, obstruction because of extracolonic malignancy, and covered stent usage. This was a retrospective, single-center study. The efficacy and safety of stent placement for malignant rectal obstruction were comparable with those for left colonic obstruction. However, obstruction attributed to extracolonic malignancy, use of covered stents, and total obstruction negatively impacted clinical outcomes

  6. Safety and efficacy of self-expandable metal stents for obstructive proximal and distal large bowel cancer.

    PubMed

    Mitra, V; Hu, M; Majumdar, D; Krishnan, V; Chaudhury, B; Hancock, J; Dwarakanath, D

    2017-03-01

    Self-expandable metal stents are often used to treat obstructive large bowel cancers. This study assessed the safety and efficacy of colonic stent insertion carried out in a district general hospital. Methods A retrospective review was carried out between 1 January 2007 and 28 February 2014 to identify patients who underwent stent insertion for malignant colorectal obstruction. Results Seventy-five patients (median age 75.2 years, 70.6% male) with primary colorectal cancer underwent stent insertion - 53 underwent semi-elective self-expanded metal stent insertion (for subacute bowel obstruction) and 22 had emergency stent inserted (for acute bowel obstruction). The majority (88%) had self-expanded metal stents inserted for palliation. Technical and clinical success rates were 98.7% and 91.2%, respectively. One patient had stent-related perforation; there was no procedure-related mortality. Conclusion This study shows that self-expanded metal stent insertion in malignant colorectal obstruction is safe and effective and can be successfully delivered in a district general hospital with high technical and clinical success rates.

  7. Self-Expandable Metallic Stent Placement for the Palliation of Esophageal Cancer.

    PubMed

    Kim, Kun Yung; Tsauo, Jiaywei; Song, Ho Young; Kim, Pyeong Hwa; Park, Jung Hoon

    2017-07-01

    Esophageal stents have been used to palliate patients with dysphagia caused by esophageal cancer. Early rigid plastic prostheses have been associated with a high risk of complications. However, with the development of self-expanding stents, it has developed into a widely accepted method for treating malignant esophageal strictures and esophagorespiratory fistulas (ERFs). The present review covers various aspects of self-expanding metallic stent placement for palliating esophageal cancer, including its types, placement procedures, indications, contraindications, complications, and some of innovations that will become available in the future. © 2017 The Korean Academy of Medical Sciences.

  8. Self-Expandable Metallic Stent Placement for the Palliation of Esophageal Cancer

    PubMed Central

    2017-01-01

    Esophageal stents have been used to palliate patients with dysphagia caused by esophageal cancer. Early rigid plastic prostheses have been associated with a high risk of complications. However, with the development of self-expanding stents, it has developed into a widely accepted method for treating malignant esophageal strictures and esophagorespiratory fistulas (ERFs). The present review covers various aspects of self-expanding metallic stent placement for palliating esophageal cancer, including its types, placement procedures, indications, contraindications, complications, and some of innovations that will become available in the future. PMID:28581260

  9. [Cost-effectiveness trial of self-expandable metal stents and plastic biliary stents in malignant biliary obstruction].

    PubMed

    Daróczi, Tímea; Bor, Renáta; Fábián, Anna; Szabó, Ella; Farkas, Klaudia; Bálint, Anita; Czakó, László; Rutka, Mariann; Szűcs, Mónika; Milassin, Ágnes; Molnár, Tamás; Szepes, Zoltán

    2016-02-14

    Self-expandable metal and plastic stents can be applied in the palliative endoscopic treatment of patients with unresectable malignant biliary obstruction. The use of metal stentsis recommended if the patient's life expectancy is more than four months. To compare the therapeutic efficacy and cost-effectiveness of metal and plastic stents in the treatment of malignant biliary obstruction. The authors retrospectively enrolled patients who received metal (37 patients) or plastic stent (37 patients). The complication rate, stent patency and cumulative cost of treatment were assessed in the two groups. The complication rate of metal stents was lower (37.84% vs. 56.76%), but the stent patency was higher compared with plastic stents (19.11 vs. 8.29 weeks; p = 0.0041). In the plastic stent group the frequency of hospitalization of patients in context with stent complications (1.18 vs. 2.32; p = 0.05) and the necessity of reintervention for stent dysfunction (17 vs. 27; p = 0.033) were substantially higher. In this group multiple stent implantation raised the stent patency from 7.68 to 10.75 weeks. There was no difference in the total cost of treatment of malignant biliary obstruction between the two groups (p = 0.848). Considering the cost of treatment and the burden of patients the authors recommend self-expandable metal sten timplantation if the life expectancy of patients is more than two months. In short survival cases multiple plastic stent implantation is recommended.

  10. Difficult removal of fully covered self expandable metal stents (SEMS) for benign biliary strictures: the "SEMS in SEMS" technique.

    PubMed

    Tringali, Andrea; Blero, Daniel; Boškoski, Ivo; Familiari, Pietro; Perri, Vincenzo; Devière, Jacques; Costamagna, Guido

    2014-06-01

    Removal of biliary Fully Covered Self Expandable Metal Stents can fail due to stent migration and/or hyperplastic ingrowth/overgrowth. A case series of 5 patients with benign biliary strictures (2 post-cholecystectomy, 2 following liver transplantation and 1 related to chronic pancreatitis) is reported. The biliary stricture was treated by temporary insertion of Fully Covered Self Expandable Metal Stents. Stent removal failed due to proximal stent migration and/or overgrowth. Metal stent removal was attempted a few weeks after the insertion of another Fully Covered Metal Stent into the first one. The inner Fully Covered Self Expandable Metal Stent compressed the hyperplastic tissue, leading to the extraction of both the stents in all cases. Two complications were reported as a result of the attempt to stents removal (mild pancreatitis and self-limited haemobilia). In the present series, the "SEMS in SEMS" technique revealed to be effective when difficulties are encountered during Fully Covered Self Expandable Metal Stents removal. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  11. Self-expandable metal stents in the treatment of benign anastomotic stricture after rectal resection for cancer.

    PubMed

    Lamazza, A; Fiori, E; Sterpetti, A V; Schillaci, A; Scoglio, D; Lezoche, E

    2014-04-01

    To evaluate the use of self-expandable metallic stents to treat patients with symptomatic benign anastomotic stricture after colorectal resection. Ten patients with a benign symptomatic anastomotic stricture after colorectal resection were treated with endoscopic placement of a self-expandable metal stent. The stent was placed successfully in all 10 patients without any major morbidity. At a mean follow-up of 18 months the stenosis was resolved successfully in 7 out 10 patients (70%). The remaining three patients were subsequently treated successfully with balloon dilatation. Self-expandable metal stents represent a valid alternative to balloon dilatation to treat patients with benign symptomatic anastomotic stricture after colorectal resection for cancer. Colorectal Disease © 2013 The Association of Coloproctology of Great Britain and Ireland.

  12. Covered duodenal self-expandable metal stents prolong biliary stent patency in double stenting: The largest series of bilioduodenal obstruction.

    PubMed

    Hori, Yasuki; Naitoh, Itaru; Hayashi, Kazuki; Kondo, Hiromu; Yoshida, Michihiro; Shimizu, Shuya; Hirano, Atsuyuki; Okumura, Fumihiro; Ando, Tomoaki; Jinno, Naruomi; Takada, Hiroki; Togawa, Shozo; Joh, Takashi

    2018-03-01

    Endoscopic biliary and duodenal stenting (DS; double stenting) is widely accepted as a palliation therapy for malignant bilioduodenal obstruction. The aim of the current study was to investigate the patency and adverse events of duodenal and biliary stents in patients with DS. Patients who underwent DS from April 2004 to March 2017 were analyzed retrospectively with regard to clinical outcomes and predictive factors of recurrent biliary and duodenal obstruction (recurrent biliary obstruction [RBO] and recurrent duodenal obstruction [RDO]). A total of 109 consecutive patients was enrolled. Technical success of DS was achieved in 108 patients (99.1%). Symptoms due to biliary and duodenal obstruction were improved in 89 patients (81.7%). RBO occurred in 25 patients (22.9%) and RDO in 13 (11.9%). The median times to RBO and RDO from DS were 87 and 76 days, respectively. Placement of a duodenal uncovered self-expandable metal stent (U-SEMS) was significantly associated with RBO in the multivariable analysis (P = 0.007). Time to RBO was significantly longer in the duodenal covered self-expandable metal stent group than in the U-SEMS group (P = 0.003). No predictive factors of RDO were detected, and duodenal stent type was not associated with the time to RDO (P = 0.724). Double stenting was safe and effective for malignant bilioduodenal obstruction. Duodenal U-SEMS is a risk factor for RBO. The covered self-expandable metal stent is the preferred type of duodenal SEMS in patients with DS (Clinical trial registration number: UMIN000027606). © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  13. Fully Covered Self-Expandable Metal Stents for Treatment of Both Benign and Malignant Biliary Disorders

    PubMed Central

    Abdel Samie, Ahmed; Theilmann, Lorenz

    2012-01-01

    Transpapillary stents are increasingly being used for biliary strictures, whether benign or malignant. However, there are different stent types and available data is controversial. Recently, completely covered self-expandable metal stents (CSEMSs) have been proposed as an alternative therapeutic option in different biliary indications, including strictures of the distal bile duct, anastomotic stenosis after orthotopic liver transplantation, bile duct leaks, periampullary perforation following endoscopic sphincterotomy (ES), and postsphincterotomy bleeding. Despite the higher costs of these devices, fully covered self-expanding metal stents seem to be a suitable therapeutic option to relief biliary obstruction due to bile duct stenosis, regardless of the underlying cause. PMID:22761543

  14. Thoracic Discitis as a Complication of Self-Expanding Metallic Stents in Esophageal Carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McQueen, A. S.; Eljabu, W.; Latimer, J., E-mail: joanne.latimer@nth.nhs.uk

    2011-02-15

    The role of metallic stents in the palliation of esophageal cancer is well established. Self-expanding metal stents (SEMSs) are frequently used, as they provide an effective and safe method of relieving malignant dysphagia. A number of complications are associated with the use of SEMSs, including esophageal perforation. We report a case of thoracic discitis occurring in a patient with advanced esophageal malignancy, treated with SEMSs. We propose that the likely etiology in this patient was esophageal perforation by a metallic stent.

  15. Predictors of the patency of self-expandable metallic stents in malignant gastroduodenal obstruction.

    PubMed

    Kim, Seung Han; Chun, Hoon Jai; Yoo, In Kyung; Lee, Jae Min; Nam, Seung Joo; Choi, Hyuk Soon; Kim, Eun Sun; Keum, Bora; Seo, Yeon Seok; Jeen, Yoon Tae; Lee, Hong Sik; Um, Soon Ho; Kim, Chang Duck

    2015-08-14

    To investigate the predictive factors of self-expandable metallic stent patency after stent placement in patients with inoperable malignant gastroduodenal obstruction. A total of 116 patients underwent stent placements for inoperable malignant gastroduodenal obstruction at a tertiary academic center. Clinical success was defined as acceptable decompression of the obstructive lesion within the malignant gastroduodenal neoplasm. We evaluated patient comorbidities and clinical statuses using the World Health Organization's scoring system and categorized patient responses to chemotherapy using the Response Evaluation Criteria in Solid Tumors criteria. We analyzed the relationships between possible predictive factors and stent patency. Self-expandable metallic stent placement was technically successful in all patients (100%), and the clinical success rate was 84.2%. In a multivariate Cox proportional hazards model, carcinoembryonic antigen (CEA) levels were correlated with a reduction in stent patency [P = 0.006; adjusted hazard ratio (aHR) = 2.92, 95%CI: 1.36-6.25]. Palliative chemotherapy was statistically associated with an increase in stent patency (P = 0.009; aHR = 0.27, 95%CI: 0.10-0.72). CEA levels can easily be measured at the time of stent placement and may help clinicians to predict stent patency and determine the appropriate stent procedure.

  16. Predictors of the patency of self-expandable metallic stents in malignant gastroduodenal obstruction

    PubMed Central

    Kim, Seung Han; Chun, Hoon Jai; Yoo, In Kyung; Lee, Jae Min; Nam, Seung Joo; Choi, Hyuk Soon; Kim, Eun Sun; Keum, Bora; Seo, Yeon Seok; Jeen, Yoon Tae; Lee, Hong Sik; Um, Soon Ho; Kim, Chang Duck

    2015-01-01

    AIM: To investigate the predictive factors of self-expandable metallic stent patency after stent placement in patients with inoperable malignant gastroduodenal obstruction. METHODS: A total of 116 patients underwent stent placements for inoperable malignant gastroduodenal obstruction at a tertiary academic center. Clinical success was defined as acceptable decompression of the obstructive lesion within the malignant gastroduodenal neoplasm. We evaluated patient comorbidities and clinical statuses using the World Health Organization’s scoring system and categorized patient responses to chemotherapy using the Response Evaluation Criteria in Solid Tumors criteria. We analyzed the relationships between possible predictive factors and stent patency. RESULTS: Self-expandable metallic stent placement was technically successful in all patients (100%), and the clinical success rate was 84.2%. In a multivariate Cox proportional hazards model, carcinoembryonic antigen (CEA) levels were correlated with a reduction in stent patency [P = 0.006; adjusted hazard ratio (aHR) = 2.92, 95%CI: 1.36-6.25]. Palliative chemotherapy was statistically associated with an increase in stent patency (P = 0.009; aHR = 0.27, 95%CI: 0.10-0.72). CONCLUSION: CEA levels can easily be measured at the time of stent placement and may help clinicians to predict stent patency and determine the appropriate stent procedure. PMID:26290640

  17. Novel biliary self-expanding metal stents: indications and applications.

    PubMed

    Blero, Daniel; Huberty, Vincent; Devière, Jacques

    2015-03-01

    Endoscopic insertion of a self-expanding metal stent (SEMS) through a malignant common bile duct stricture is the first line of palliation for malignant jaundice. Patency of these stents remains a major concern. SEMS dysfunction can result from tumor ingrowth, overgrowth and/or clogging. Initial SEMS modifications involved covering the central part of the stent in order to reduce ingrowth and ultimately increase patency. Fully covered stents became available shortly after reports of their use in human patients. The potential removability and radial strength of SEMS have led to evaluation of their use in new indications including benign biliary strictures, post sphincterotomy bleeding and perforation. Other aspects of development include the addition of features such as anti-reflux valves, drug elution and spontaneous biodegradability. These aspects and their clinical implications are reviewed and discussed.

  18. Successful removal of self-expanding metallic stent after deployment for tubercular bronchostenosis.

    PubMed

    Isaac, Barney Thomas Jesudason; Datey, Ashima; Christopher, Devasahayam Jesudas

    2016-01-01

    The use of metallic stents is traditionally not recommended for benign tracheobronchial conditions. With advances in the field of interventional bronchoscopy, metal tracheobronchial stents have occasionally been used to treat benign disease. However, the removal of these stents from the airway is technically difficult. We are reporting the case of a young female subject who received a self-expanding metallic stent for alleviation of post-tubercular bronchostenosis, which was successfully removed after two months without complications. Metal stents can be used in benign tracheobronchial conditions but require meticulous follow-up to monitor complications. Experienced operators can remove them without major complications and this may be life-saving in emergencies. We are reporting this case for the rarity of such procedures in India. Copyright © 2015 Tuberculosis Association of India. Published by Elsevier B.V. All rights reserved.

  19. Self-expandable metal stents for malignant colonic obstruction: data from a retrospective regional SIED-AIGO study.

    PubMed

    Di Mitri, Roberto; Mocciaro, Filippo; Traina, Mario; Montalbano, Luigi Maria; Familiari, Luigi; D'Amore, Fabio; Raimondo, Dario; Virgilio, Clara; Tarantino, Ilaria; Barresi, Luca; Giunta, Marco; Borina, Eleonora; Borruto, Antonino; Marino, Antonino

    2014-03-01

    Self-expandable metal stents are a non-surgical option for the treatment of symptomatic malignant colorectal obstruction as palliative treatment or as a bridge to surgery. To report data from a regional study on self-expandable metal stent (SEMS) placement for malignant colorectal obstruction. Two hundred and four patients (male 54.9%, mean age of 69.5 ± 14.2) were retrospectively evaluated and data on technical and clinical success, and complications, were analyzed. Technical and clinical success rates were 99% and 94.6% respectively, with 36.7% treated on an emergency basis and 63.3% electively. Palliative treatment was administered to 70.1%, and as a bridge to surgery for 29.9%. Complications were 17 neoplastic ingrowths, 10 stent migrations, and 4 perforations. Palliative treatment was associated with a higher risk of stent ingrowth (p=0.003), and chemotherapy with a lower risk of stent ingrowth (p=0.009). This regional study, although it has certain limitations, confirms the positive role of self-expandable metal stents in the treatment of symptomatic malignant colorectal obstruction, and that chemotherapy decreases the risk of ingrowth. Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  20. Anesthesia and airway management for removing pulmonary self-expanding metallic stents.

    PubMed

    Doyle, D John; Abdelmalak, Basem; Machuzak, Michael; Gildea, Thomas R

    2009-11-01

    The use of bronchoscopically placed self-expanding metallic stents (SEMS) and silastic stents in patients suffering from tracheobronchial stenosis or similar problems has proven to be an important clinical option. When complications occur, it may be necessary to remove the device. Removal of a SEMS is usually performed during general anesthesia with muscle relaxation and positive pressure ventilation, often using total intravenous anesthesia. Airway management depends on stent type and location. Intubating patients' tracheas with a tracheal stent requires special caution, as it risks damaging tissue and dislodging the stent distally. Potential complications with removal include tracheal disruption, retained stent pieces, mucosal tears, re-obstruction requiring new stent placement, the need for postoperative ventilation, pneumothorax, damage to the pulmonary artery, and death.

  1. Comparison of covered and uncovered self-expandable stents in the treatment of malignant biliary obstruction.

    PubMed

    Flores Carmona, Diana Yamel; Alonso Lárraga, Juan Octavio; Hernández Guerrero, Angélica; Ramírez Solís, Mauro Eduardo

    2016-05-01

    Drainage with metallic stents is the treatment of choice in malignant obstructive jaundice. Technical and clinical success with metallic stents is obtained in over 90% and 80% of cases, respectively. There are self-expandable metallic stents designed to increase permeability. The aim of this study was to describe the results obtained with totally covered self-expandable and uncovered self-expandable metallic stents in the palliative treatment of malignant biliary obstruction. Sixty eight patients with malignant obstructive jaundice secondary to pancreatobiliary or metastatic disease not amenable to surgery were retrospectively included. Two groups were created: group A (covered self-expandable metallic stents) (n = 22) and group B (uncovered self-expandable metallic stents) (n = 46). Serum total bilirubin, direct bilirubin, alkaline phosphatase and gamma glutamyl transferase levels decreased in both groups and no statistically significant difference was detected (p = 0.800, p = 0.190, p = 0.743, p = 0.521). Migration was greater with covered stents but it was not statistically significant either (p = 0.101). Obstruction was greater in the group with uncovered stents but it was not statistically significant either (p = 0.476). There are no differences when using covered self-expandable stents or uncovered self-expandable stents in terms of technical and clinical success or complications in the palliative treatment of malignant obstructive jaundice.

  2. Evaluation of anti-migration properties of biliary covered self-expandable metal stents

    PubMed Central

    Minaga, Kosuke; Kitano, Masayuki; Imai, Hajime; Harwani, Yogesh; Yamao, Kentaro; Kamata, Ken; Miyata, Takeshi; Omoto, Shunsuke; Kadosaka, Kumpei; Sakurai, Toshiharu; Nishida, Naoshi; Kudo, Masatoshi

    2016-01-01

    AIM: To assess anti-migration potential of six biliary covered self-expandable metal stents (C-SEMSs) by using a newly designed phantom model. METHODS: In the phantom model, the stent was placed in differently sized holes in a silicone wall and retracted with a retraction robot. Resistance force to migration (RFM) was measured by a force gauge on the stent end. Radial force (RF) was measured with a RF measurement machine. Measured flare structure variables were the outer diameter, height, and taper angle of the flare (ODF, HF, and TAF, respectively). Correlations between RFM and RF or flare variables were analyzed using a linear correlated model. RESULTS: Out of the six stents, five stents were braided, the other was laser-cut. The RF and RFM of each stent were expressed as the average of five replicate measurements. For all six stents, RFM and RF decreased as the hole diameter increased. For all six stents, RFM and RF correlated strongly when the stent had not fully expanded. This correlation was not observed in the five braided stents excluding the laser cut stent. For all six stents, there was a strong correlation between RFM and TAF when the stent fully expanded. For the five braided stents, RFM after full stent expansion correlated strongly with all three stent flare structure variables (ODF, HF, and TAF). The laser-cut C-SEMS had higher RFMs than the braided C-SEMSs regardless of expansion state. CONCLUSION: RF was an important anti-migration property when the C-SEMS did not fully expand. Once fully expanded, stent flare structure variables plays an important role in anti-migration. PMID:27570427

  3. Evaluation of anti-migration properties of biliary covered self-expandable metal stents.

    PubMed

    Minaga, Kosuke; Kitano, Masayuki; Imai, Hajime; Harwani, Yogesh; Yamao, Kentaro; Kamata, Ken; Miyata, Takeshi; Omoto, Shunsuke; Kadosaka, Kumpei; Sakurai, Toshiharu; Nishida, Naoshi; Kudo, Masatoshi

    2016-08-14

    To assess anti-migration potential of six biliary covered self-expandable metal stents (C-SEMSs) by using a newly designed phantom model. In the phantom model, the stent was placed in differently sized holes in a silicone wall and retracted with a retraction robot. Resistance force to migration (RFM) was measured by a force gauge on the stent end. Radial force (RF) was measured with a RF measurement machine. Measured flare structure variables were the outer diameter, height, and taper angle of the flare (ODF, HF, and TAF, respectively). Correlations between RFM and RF or flare variables were analyzed using a linear correlated model. Out of the six stents, five stents were braided, the other was laser-cut. The RF and RFM of each stent were expressed as the average of five replicate measurements. For all six stents, RFM and RF decreased as the hole diameter increased. For all six stents, RFM and RF correlated strongly when the stent had not fully expanded. This correlation was not observed in the five braided stents excluding the laser cut stent. For all six stents, there was a strong correlation between RFM and TAF when the stent fully expanded. For the five braided stents, RFM after full stent expansion correlated strongly with all three stent flare structure variables (ODF, HF, and TAF). The laser-cut C-SEMS had higher RFMs than the braided C-SEMSs regardless of expansion state. RF was an important anti-migration property when the C-SEMS did not fully expand. Once fully expanded, stent flare structure variables plays an important role in anti-migration.

  4. Obstruction after Self-expanding Metallic Stents in Tuberculous Bronchial Stenosis

    PubMed Central

    Kim, Won; Lee, Youg Chul; Rhee, Yang Keun

    1995-01-01

    Expandable metallic stents seemed to be a good method in tuberculous bronchial stenosis that does not respond to medical therapy. But there was no long-term follow-up study after stents insertion in tuberculous bronchial stenosis. We report a case of obstruction after successful Gianturco metallic stents insertion due to tuberculous bronchial stenosis. PMID:7542914

  5. Self-Expandable Metallic Stent Placement in Malignant Gastric Outlet Obstruction

    PubMed Central

    Ye, Bing-Wei; Lee, Kuei-Chuan; Hsieh, Yun-Cheng; Li, Chung-Pin; Chao, Yee; Hou, Ming-Chih; Lin, Han-Chieh

    2015-01-01

    Abstract Malignant gastric outlet obstruction is a late complication of intraabdominal malignancy. Self-expandable metallic stent placement has been a safe palliative treatment to relieve obstructive symptoms. We aimed to assess the efficacy and safety of metallic stents in our patients and analyzed the clinical outcome of different brands. Seventy-one patients with inoperable gastric outlet obstruction receiving WallFlex enteral stents (WallFlex group) or Bonastents (Bonastent group) since April 2010 were analyzed retrospectively. The overall technical and clinical success rates of stent placement were 100% and 93%, respectively. The baseline characteristics and clinical outcomes including procedure-related complications, restenosis, and reintervention rates were comparable between the 2 groups. However, the Bonastent group had a higher rate of stent fracture than the WallFlex group (13.3% vs 0%, P = 0.03). The mean duration of overall stent patency was 132.7 days. The mean duration of survival was 181.9 days. Resumption of regular diet or low residual diet at day 7 after stent insertion predicted stent patency (hazard ratio [HR]: 0.28, P = 0.01). Cancer with gastric origin (HR: 0.25, P = 0.045) and poststent chemotherapy (HR: 0.38, P = 0.006) predicted lower mortality; however, peritoneal carcinomatosis (HR: 3.09, P = 0.04) correlated with higher mortality. Metallic stent placement is a safe and effective method for relieving gastric outlet obstruction. Except higher rate of stent fracture in the Bonastent group, there is no significant difference in clinical outcomes between the Bonastent group and the WallFlex group. PMID:26200641

  6. Covered self-expandable metal stents for benign biliary tract diseases.

    PubMed

    Baron, Todd H

    2011-05-01

    Benign biliary diseases are often managed endoscopically using plastic stents. Benign biliary strictures (BBS) respond to placement of multiple large-bore plastic stents, though requiring multiple procedures to place stents, and to exchange stents to prevent and/or treat stent occlusion. Bile leaks close using plastic stents, which divert bile away from the leak into the duodenum. Covered self-expandable metal stents (CSEMS), intended for palliation of malignant biliary obstruction, have been used to treat benign biliary diseases. Advantages include small predeployment and large postexpansion diameters. Lack of imbedding of the metal into the bile duct wall enables removability. For strictures, one CSEMS is inserted without need for dilation and remains in place for up to 6 months. Successful removal has been reported in all cases. Long-term stricture resolution is achieved in up to 92%. Adverse events include migration and new stricture formation. For treatment of complex bile leaks, the covering and large diameter allow successful closure in nearly all cases. Other uses of CSEMS include treatment of postsphincterotomy bleeding and closure of perforations. CSEMS show promise for treatment of BBS and complex biliary leaks. Successful resolution can be achieved in the majority of patients with the advantage of fewer procedures, which offsets their higher cost.

  7. Role of laser photoablative therapy and expandable metal stents in colorectal carcinoma

    NASA Astrophysics Data System (ADS)

    Chennupati, Raja S.; Trowers, Eugene A.

    2000-05-01

    Metallic stents are effective in relieving colorectal obstruction in more than 80% of cases. Self expanding metallic stents allow for decompression of the proximal colon and preoperative bowel cleansing. Hence, emergent surgery for large bowel obstruction with its associated high morbidity and mortality might be avoided. Endoscopic laser photoablation and stent placement may successfully palliate inoperable colorectal cancer patients by maintaining luminal patency and avoiding the need for a colostomy. Major complications associated with metallic stents include pressure necrosis, perforation, bleeding and migration. The effectiveness of expandable metallic stents in obstructive colorectal carcinoma is critically reviewed. The authors present a concise review of the effectiveness of endoscopic laser photoablation and expandable metal stent placement.

  8. Improvement of quality of life and survival using self-expandable metal stent placement for severe malignant stenosis of the gastric body: a case report.

    PubMed

    Kumagai, Hozumi; Nio, Kenta; Shirakawa, Tsuyoshi; Uchino, Keita; Kusaba, Hitoshi; Isobe, Taichi; Komoda, Masato; Tamura, Shingo; Maeyama, Ryo; Nagai, Eishi; Akashi, Koichi; Baba, Eishi

    2012-09-19

    Advanced gastric carcinoma often decreases quality of life because of upper gastrointestinal tract stenosis. Self-expandable metal stents have been thought to be an effective, minimally invasive treatment for stenosis. However, the effectiveness of self-expandable metal stent placement for carcinomatous stenosis of the gastric body and antrum has not been clarified, and there have been few reports of such cases. A 74-year-old Japanese woman developed stenosis of the gastric body and antrum caused by advanced gastric cancer during first-line chemotherapy. She developed weight loss and poor nutrition due to inadequate intake. Self-expandable metal stent placement for stenosis of the gastric body and antrum ameliorated her symptoms rapidly and improved her general condition and quality of life. Eight days after self-expandable metal stent placement, second-line chemotherapy could be administered safely. Oral intake and nutritional status were maintained for 117 days after self-expandable metal stent placement, and she died of gastric cancer 176 days after self-expandable metal stent placement and initiation of second-line chemotherapy. Self-expandable metal stent placement for carcinomatous stenosis in the gastric body and antrum could be an effective therapeutic strategy for patients with inadequate oral uptake. It may provide rapid improvement of the patient's general condition and oral intake with minimal complications, comparatively long-term symptom relief, and a survival benefit by allowing second-line chemotherapy.

  9. Role of fully covered self-expandable metal stent for treatment of benign biliary strictures and bile leaks.

    PubMed

    Pausawasadi, Nonthalee; Soontornmanokul, Tanassanee; Rerknimitr, Rungsun

    2012-01-01

    Endoscopic therapy by balloon dilation and placement of multiple large-bore plastic stents is the treatment of choice for benign biliary stricture. This approach is effective but it typically requires multiple endoscopic sessions given the short duration of stent patency. The endoscopic approach for treatment of bile leak involves the placement of a stent with or without biliary sphincterotomy. The self-expandable metal stent (SEMS) has traditionally been used for palliation of malignant biliary strictures given the long duration of stent patency owing to their larger stent diameter. Recently, SEMS has been used in a variety of benign biliary strictures and leaks, especially with the design of the covered self-expandable metal stent (CSEMS), which permits endoscopic-mediated stent removal. The use of CSEMS in benign biliary stricture could potentially result in a decrease in endoscopic sessions and it is technically easier when compared to placement of multiple plastic stents. However, complications such as cholecystitis due to blockage of cystic duct, stent migration, infection and pancreatitis have been reported. The potential subsegmental occlusion of contralateral intrahepatic ducts also limits the use of CSEMS in hilar stricture. Certain techniques and improvement of stent design may overcome these challenges in the future. Thus, CSEMS may be appropriate in only highly selected conditions, such as refractory benign biliary stricture, despite multiple plastic stent placement or difficult to treat bile duct stricture from chronic pancreatitis, and should not be used routinely. This review focuses on the use of fully covered self-expandable metal stent for benign biliary strictures and bile leaks.

  10. Role of Fully Covered Self-Expandable Metal Stent for Treatment of Benign Biliary Strictures and Bile Leaks

    PubMed Central

    Pausawasadi, Nonthalee; Soontornmanokul, Tanassanee

    2012-01-01

    Endoscopic therapy by balloon dilation and placement of multiple large-bore plastic stents is the treatment of choice for benign biliary stricture. This approach is effective but it typically requires multiple endoscopic sessions given the short duration of stent patency. The endoscopic approach for treatment of bile leak involves the placement of a stent with or without biliary sphincterotomy. The self-expandable metal stent (SEMS) has traditionally been used for palliation of malignant biliary strictures given the long duration of stent patency owing to their larger stent diameter. Recently, SEMS has been used in a variety of benign biliary strictures and leaks, especially with the design of the covered self-expandable metal stent (CSEMS), which permits endoscopic-mediated stent removal. The use of CSEMS in benign biliary stricture could potentially result in a decrease in endoscopic sessions and it is technically easier when compared to placement of multiple plastic stents. However, complications such as cholecystitis due to blockage of cystic duct, stent migration, infection and pancreatitis have been reported. The potential subsegmental occlusion of contralateral intrahepatic ducts also limits the use of CSEMS in hilar stricture. Certain techniques and improvement of stent design may overcome these challenges in the future. Thus, CSEMS may be appropriate in only highly selected conditions, such as refractory benign biliary stricture, despite multiple plastic stent placement or difficult to treat bile duct stricture from chronic pancreatitis, and should not be used routinely. This review focuses on the use of fully covered self-expandable metal stent for benign biliary strictures and bile leaks. PMID:22563290

  11. Comparison of self-expandable and balloon-expanding stents for hybrid ductal stenting in hypoplastic left heart complex.

    PubMed

    Goreczny, Sebastian; Qureshi, Shakeel A; Rosenthal, Eric; Krasemann, Thomas; Nassar, Mohamed S; Anderson, David R; Morgan, Gareth J

    2017-07-01

    We aimed to compare the procedural and mid-term performance of a specifically designed self-expanding stent with balloon-expandable stents in patients undergoing hybrid palliation for hypoplastic left heart syndrome and its variants. The lack of specifically designed stents has led to off-label use of coronary, biliary, or peripheral stents in the neonatal ductus arteriosus. Recently, a self-expanding stent, specifically designed for use in hypoplastic left heart syndrome, has become available. We carried out a retrospective cohort comparison of 69 neonates who underwent hybrid ductal stenting with balloon-expandable and self-expanding stents from December, 2005 to July, 2014. In total, 43 balloon-expandable stents were implanted in 41 neonates and more recently 47 self-expanding stents in 28 neonates. In the balloon-expandable stents group, stent-related complications occurred in nine patients (22%), compared with one patient in the self-expanding stent group (4%). During follow-up, percutaneous re-intervention related to the ductal stent was performed in five patients (17%) in the balloon-expandable stent group and seven patients (28%) in self-expanding stents group. Hybrid ductal stenting with self-expanding stents produced favourable results when compared with the results obtained with balloon-expandable stents. Immediate additional interventions and follow-up re-interventions were similar in both groups with complications more common in those with balloon-expandable stents.

  12. Placement of retrievable self-expandable metallic stents with barbs into patients with obstructive prostate cancer.

    PubMed

    Song, Ho-Young; Kim, Choung Soo; Jeong, In Gab; Yoo, Dalsan; Kim, Jin Hyoung; Nam, Deok Ho; Bae, Jae-Ik; Park, Jung-Hoon

    2013-03-01

    To evaluate the technical feasibility and clinical effectiveness of retrievable self-expandable metallic stents with barbs in patients with obstructive prostate cancer. Retrievable self-expandable metallic stents with eight barbs each were inserted into eight consecutive patients with obstructive prostate cancer. Patient ages ranged from 55 to 76 years (mean, 69 years). All eight patients had previously received hormone therapy, and three had undergone palliative transurethral prostatectomy. Stents were removed using a 21-F stent removal set if they caused complications. Stent placement was technically successful and well tolerated in all patients. One had severe incontinence, which improved spontaneously, and two had gross haematuria, which disappeared spontaneously within 4 days. Peak urine flow rates and post-void residual urine volumes 1 month after stent placement were 5.6-10.2 ml/s (mean, 8.3 ml/s), and 5-45 ml (mean, 27 ml), respectively. During a mean follow-up of 192 days (range, 39-632 days), one patient required stent removal after 232 days because of stone formation within the stent. No further intervention was required because the mass improved after stent removal. These preliminary results suggest that retrievable stents with eight barbs are both feasible to place and effective in patients with obstructive prostate cancer.

  13. Chemotherapy versus self-expanding metal stent as primary treatment of severe dysphagia from unresectable oesophageal or gastro-oesophageal junction cancer.

    PubMed

    Touchefeu, Yann; Archambeaud, Isabelle; Landi, Bruno; Lièvre, Astrid; Lepère, Céline; Rougier, Philippe; Mitry, Emmanuel

    2014-03-01

    To compare chemotherapy first (group 1) versus self-expanding metal stent first (group 2) for the management of malignant dysphagia in unresectable oesophageal or gastro-oesophageal junction cancer. Patients from two university hospitals with severe malignant dysphagia (dysphagia score ≥ 2) uneligible for surgery or radiochemotherapy were evaluated retrospectively. Forty-two patients were included in group 1, and 29 in group 2. After 4 weeks, dysphagia scores improved by at least 1 point in 67% of patients in group 1 versus 93% in group 2 (p=0.01); 48% of patients in group 1 were able to eat solid food versus 68% in group 2 (p=0.054). In group 1, a self-expanding metal stent was secondarily placed in 18 patients (42.9%), whereas in group 2 dysphagia required a second self-expanding metal stent placement in 33.3% of patients. Chemotherapy as the first treatment may be a valid option, avoiding self-expanding metal stent insertion in half of the patients. Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  14. Fully covered self-expandable metal stents (SEMS), partially covered SEMS and self-expandable plastic stents for the treatment of benign esophageal ruptures and anastomotic leaks.

    PubMed

    van Boeckel, Petra G A; Dua, Kulwinder S; Weusten, Bas L A M; Schmits, Ruben J H; Surapaneni, Naveen; Timmer, Robin; Vleggaar, Frank P; Siersema, Peter D

    2012-02-29

    Benign esophageal ruptures and anastomotic leaks are life-threatening conditions that are often treated surgically. Recently, placement of partially and fully covered metal or plastic stents has emerged as a minimally invasive treatment option. We aimed to determine the clinical effectiveness of covered stent placement for the treatment of esophageal ruptures and anastomotic leaks with special emphasis on different stent designs. Consecutive patients who underwent placement of a fully covered self-expandable metal stent (FSEMS), a partially covered SEMS (PSEMS) or a self-expanding plastic stent (SEPS) for a benign esophageal rupture or anastomotic leak after upper gastrointestinal surgery in the period 2007-2010 were included. Data on patient demographics, type of lesion, stent placement and removal, clinical success and complications were collected A total of 52 patients received 83 esophageal stents (61 PSEMS, 15 FSEMS, 7 SEPS) for an anastomotic leak (n=32), iatrogenic rupture (n=13), Boerhaave's syndrome (n=4) or other cause (n=3). Endoscopic stent removal was successful in all but eight patients treated with a PSEMS due to tissue ingrowth. Clinical success was achieved in 34 (76%, intention-to-treat: 65%) patients (PSEMS: 73%, FSEMS: 83%, SEPS: 83%) after a median of 1 (range 1-5) stent and a median stenting time of 39 (range 7-120) days. In total, 33 complications in 24 (46%) patients occurred (tissue in- or overgrowth (n=8), stent migration (n=10), ruptured stent cover (all Ultraflex; n=6), food obstruction (n=3), severe pain (n=2), esophageal rupture (n=2), hemorrhage (n=2)). One (2%) patient died of a stent-related cause. Covered stents placed for a period of 5-6 weeks may well be an alternative to surgery for treating benign esophageal ruptures or anastomotic leaks. As efficacy between PSEMS, FSEMS and SEPS is not different, stent choice should depend on expected risks of stent migration (SEPS and FSEMS) and tissue in- or overgrowth (PSEMS).

  15. Fully covered self-expandable metal stents (SEMS), partially covered SEMS and self-expandable plastic stents for the treatment of benign esophageal ruptures and anastomotic leaks

    PubMed Central

    2012-01-01

    Background Benign esophageal ruptures and anastomotic leaks are life-threatening conditions that are often treated surgically. Recently, placement of partially and fully covered metal or plastic stents has emerged as a minimally invasive treatment option. We aimed to determine the clinical effectiveness of covered stent placement for the treatment of esophageal ruptures and anastomotic leaks with special emphasis on different stent designs. Methods Consecutive patients who underwent placement of a fully covered self-expandable metal stent (FSEMS), a partially covered SEMS (PSEMS) or a self-expanding plastic stent (SEPS) for a benign esophageal rupture or anastomotic leak after upper gastrointestinal surgery in the period 2007-2010 were included. Data on patient demographics, type of lesion, stent placement and removal, clinical success and complications were collected Results A total of 52 patients received 83 esophageal stents (61 PSEMS, 15 FSEMS, 7 SEPS) for an anastomotic leak (n = 32), iatrogenic rupture (n = 13), Boerhaave's syndrome (n = 4) or other cause (n = 3). Endoscopic stent removal was successful in all but eight patients treated with a PSEMS due to tissue ingrowth. Clinical success was achieved in 34 (76%, intention-to-treat: 65%) patients (PSEMS: 73%, FSEMS: 83%, SEPS: 83%) after a median of 1 (range 1-5) stent and a median stenting time of 39 (range 7-120) days. In total, 33 complications in 24 (46%) patients occurred (tissue in- or overgrowth (n = 8), stent migration (n = 10), ruptured stent cover (all Ultraflex; n = 6), food obstruction (n = 3), severe pain (n = 2), esophageal rupture (n = 2), hemorrhage (n = 2)). One (2%) patient died of a stent-related cause. Conclusions Covered stents placed for a period of 5-6 weeks may well be an alternative to surgery for treating benign esophageal ruptures or anastomotic leaks. As efficacy between PSEMS, FSEMS and SEPS is not different, stent choice should depend on expected risks of stent migration (SEPS

  16. Application of self-expandable metal stents for ureteroileal anastomotic strictures: long-term results.

    PubMed

    Liatsikos, Evangelos N; Kagadis, George C; Karnabatidis, Dimitrios; Katsanos, Konstantinos; Papathanassiou, Zafiria; Constantinides, Constantinos; Perimenis, Petros; Nikiforidis, George C; Stolzenburg, Jens-Uwe; Siablis, Dimitrios

    2007-07-01

    We report our long-term experience with the management of benign ureteroileal anastomotic strictures using self-expandable metal stents. A total of 16 male and 2 female patients with a mean+/-SD age of 72+/-7 years (range 66 to 78) with benign fibrotic strictures at the site of ureteroileal anastomosis underwent implantation of self-expandable metal stents with a nominal diameter of 6 to 8 mm. A total of 24 ureteroileal conduits were treated. The external nephrostomy tubes were removed after fluoroscopic validation of ureteral patency. Patients were followed with blood biochemistry, ultrasonography, urography and/or virtual endoscopy. Retrograde external-internal catheter insertion through the cutaneous stoma was performed in cases of recalcitrant stricture. The technical success rate of ureteroileal stricture crossing and stenting was 100% (24 of 24 cases). Mean followup was 21 months (range 7 to 50). The clinical success rate during the immediate post-stenting period was 70.8% (17 of 24 cases). The 1 and 4-year primary patency rates were 37.8% and 22.7%, respectively. Secondary interventions included repeat balloon dilation in 15 ureters, of which 8 also underwent subsequent coaxial stent placement. The 1 and 4-year secondary patency rates were 64.8% and 56.7%, respectively. Except in 2 patients who died external-internal Double-J catheters continued to be inserted retrograde in 6 ureteroileal conduits. They are periodically exchanged to prevent mucous inspissation and stent encrustation. Metal stents served as the definitive treatment for stricture in more than half of the cases, whereas in the remainder the stents allowed the uncomplicated and regular exchange of Double-J catheters in retrograde fashion. This combined, less invasive treatment for ureteroileal anastomotic strictures may help patients avoid surgical revision and preserve quality of life.

  17. Clinical Application of Fully Covered Self-Expandable Metal Stents in the Treatment of Bronchial Fistula.

    PubMed

    Cao, Ming; Zhu, Qiang; Wang, Wei; Zhang, Tian Xiao; Jiang, Min Zhong; Zang, Qi

    2016-09-01

    Background The study was designed to access the feasibility, safety, and efficacy of fully covered self-expandable metal stents in the treatment of bronchial fistula. Methods Clinical data of nine patients (seven males and two females) who were treated with placement of tracheobronchial or bronchial fully covered self-expandable metal stents from August 2005 to November 2011 were analyzed retrospectively. Among these patients, seven were diagnosed with bronchopleural fistula, one with tracheopleural fistula, and one with left main bronchoesophageal fistula. Eight had accompanying thoracic empyema. The fistula orifices ranged from 3.5 mm to 25 mm in diameter. All patients received topical anesthesia. L-shaped stents were placed in six patients and I-shaped stents in three under fluoroscopic guidance. After stent placement, patients with empyema were treated with pleural lavage. Results Stent placement in the tracheobronchial tree was successful in all patients, without procedure-related complications. The operating time was 5 to 16 minutes. A small amount of bubble overflowed from the intrathoracic drainage tube of only one patient. In the other patients, the bubble in the intrathoracic drainage tube disappeared immediately or angiography showed no overflow of contrast agent from the fistula orifice. The effective rate of fistula orifice closure after stent placement was 100%, with 88.9% rated as excellent. One patient coughed the stent out 5 days after placement and hence a new stent was placed. Among the patients with empyema, one died of septicemia arising from empyema on day 8 and another died of brain metastases of lung cancer 6 months after stent insertion with persistent empyema. In the other six patients, empyema resolved after 2 to 5 months (cure rate 75%). Seven patients were followed up for 3 to 36 months. During follow-up, one stent was removed 8 months after implantation due to difficult expectoration, without recurrent empyema. The remaining

  18. Predictors of stent dysfunction after self-expandable metal stent placement for malignant gastric outlet obstruction: tumor ingrowth in uncovered stents and migration of covered stents.

    PubMed

    Hori, Yasuki; Naitoh, Itaru; Hayashi, Kazuki; Ban, Tesshin; Natsume, Makoto; Okumura, Fumihiro; Nakazawa, Takahiro; Takada, Hiroki; Hirano, Atsuyuki; Jinno, Naruomi; Togawa, Shozo; Ando, Tomoaki; Kataoka, Hiromi; Joh, Takashi

    2017-10-01

    Endoscopic metallic stenting is widely accepted as a palliation therapy for malignant gastric outlet obstruction (GOO). However, the predictors of stent dysfunction have not been clarified. We aimed to evaluate the predictors, especially tumor ingrowth in uncovered self-expandable metallic stents (U-SEMS) and migration of covered self-expandable metallic stents (C-SEMS), which are the main causes related to the stent characteristics. In this multicenter retrospective study, we compared patients with U-SEMS and C-SEMS in terms of clinical outcomes, and predictors of stent dysfunction. In total, 252 patients (126 with U-SEMS and 126 with C-SEMS) were enrolled. There were no significant differences in technical success, clinical success, GOO score, or time to stent dysfunction. Tumor ingrowth was significantly more frequent in U-SEMS (U-SEMS, 11.90% vs. C-SEMS, 0.79%; p = 0.002), and stent migration was significantly more frequent for C-SEMS (C-SEMS, 8.73% vs. U-SEMS, 0.79%; p = 0.005). Karnofsky performance status (p = 0.04), no presence of ascites (p = 0.02), and insufficient (<30%) stent expansion (p = 0.003) were significantly associated with tumor ingrowth in U-SEMS. Meanwhile, a shorter stent length (p = 0.05) and chemotherapy (p = 0.03) were predictors of C-SEMS migration. Both U-SEMS and C-SEMS are effective with comparable patencies. Tumor ingrowth and stent migration are the main causes of stent dysfunction for U-SEMS and C-SEMS, respectively. With regard to stent dysfunction, U-SEMS might be a good option for patients receiving chemotherapy, while C-SEMS with longer stents for patients in good condition. (Clinical trial registration number: UMIN000024059).

  19. Use of Self-Expanding Metallic Ureteral Stents in the Secondary Treatment of Ureteral Stenosis Following Kidney Transplantation.

    PubMed

    Xu, Guibin; Li, Xun; He, Yongzhong; Zhao, Haibo; Yang, Weiqing; Xie, Qingling

    2015-10-01

    To evaluate the safety and efficacy of self-expanding metal stents in the treatment of ureteral stenosis following kidney transplantation. Seven patients who developed benign stenosis after kidney transplantation were treated by a self-expanding metallic stent implantation from June 2007 to March 2014. All patients had undergone at least one open surgical procedure and one endourologic procedure for treatment of the stenosis. The extent of stenosis varied from 1.2 to 3.7 cm. Ultrasonography, urography, diuretic renography, and urine culture were performed every 3 months after stent insertion. Ureteroscopic examination was performed when needed. Stent placement was technically effective in all cases. The mean operative time was 37 minutes (range, 26-59 minutes). Lower urinary-tract symptoms and the ipsilateral flank pain were common early-stage complications and were greatly relieved after an average of 3 months. The mean follow-up duration was 38 months (range, 13-86 months), and no stent migration or fragmentation was observed. Urothelial hyperplasia occurred in only one patient and was effectively managed with a Double-J stent. Five patients had normal stable renal function; the remaining two had impaired renal function, including one patient with a preoperative renal failure who required dialysis at the end of the follow-up period (36 months). As an alternative to open surgery, implantation of a self-expanding metal stent is a safe and effective treatment for ureteral stenosis in patients who have undergone kidney transplantation.

  20. Fluoroscopically guided placement of self-expandable metallic stents and stent-grafts in the treatment of acute malignant colorectal obstruction.

    PubMed

    Kim, Honsoul; Kim, Seung Hyoung; Choi, Sun Young; Lee, Kwang-Hun; Won, Jong Yoon; Lee, Do Yun; Lee, Jong Tae

    2008-12-01

    To evaluate the technical feasibility and clinical effectiveness of fluoroscopically guided placement of self-expandable metallic stents and stent-grafts for acute malignant colorectal obstruction. Radiologic images and clinical reports of 42 patients (22 men, 20 women; age range, 28-93 years; median age, 65.5 years) who underwent fluoroscopically guided colorectal stent insertion without endoscopic assistance for acute malignant obstruction were reviewed retrospectively. Eighteen patients received bare stents as a bridge to surgery. Twenty-four patients received 27 insertions of either a bare stent (n = 15) or a stent-graft (n = 12) for palliation. The obstruction was located in the rectum (n = 8), sigmoid (n = 17), descending colon (n = 8), splenic flexure (n = 3), and transverse colon (n = 6). Clinical success, defined as more than 50% dilatation of the stent with subsequent symptomatic improvement, was achieved in 41 of the 42 patients (98%). No major procedure-related complications occurred. Minor complications occurred in eight of the 45 procedures (18%). No perioperative mortalities occurred within 1 month after surgery. In the palliative group, the median stent patency was 62 days (range, 0-1,014 days). There was no statistically significant difference in stent patency between the bare stents (range, 0-855 days; median, 68 days) and stent-grafts (range, 1-1,014 days; median, 81 days). Fluoroscopically guided placement of self-expandable metallic stents and stent-grafts for the relief of acute malignant colorectal obstruction was technically feasible without endoscopic assistance-even in lesions proximal to the splenic flexure and transverse colon-and clinically effective in both bridge to surgery and palliative management.

  1. Outcomes of secondary self-expandable metal stents versus surgery after delayed initial palliative stent failure in malignant colorectal obstruction.

    PubMed

    Yoon, Jin Young; Park, Soo Jung; Hong, Sung Pil; Kim, Tae Il; Kim, Won Ho; Cheon, Jae Hee

    2013-01-01

    When re-intervention is required due to an occluded first colorectal self-expanding metal stent for malignant colorectal obstruction, serious controversies exist regarding whether to use endoscopic re-stenting or surgery. To compare the clinical outcomes in patients who underwent stent re-insertion versus palliative surgery as a second intervention. A total of 115 patients who received either self-expandable metal stent (SEMS) insertion or palliative surgery for treatment of a second occurrence of malignant colorectal obstruction after the first SEMS placement were retrospectively studied between July 2005 and December 2009. The median overall survival (8.2 vs. 15.5 months) and progression-free survival (4.0 vs. 2.7 months) were not significantly different between the stent and surgery groups (p = 0.895 and 0.650, respectively). The median lumen patency in the stent group was 3.4 months and that in the surgery group was 7.9 months (p = 0.003). The immediate complication rate after second stent insertion was 13.9% and late complication rate was observed in 12 of 79 (15.2%) patients. There was no mortality related to the SEMS procedure. The complication and mortality rates associated with palliative surgery were 3.5% (2/57) and 12.3% (7/57), respectively. Although there is no significant difference in the overall survival between stenting and surgery, a secondary stent insertion had a lower mortality rate despite a shorter duration of temporary colorectal decompression compared to that of palliative surgery.

  2. Endoscopic removal and trimming of distal self-expandable metallic biliary stents

    PubMed Central

    Ishii, Kentaro; Itoi, Takao; Sofuni, Atsushi; Itokawa, Fumihide; Tsuchiya, Takayoshi; Kurihara, Toshio; Tsuji, Shujiro; Ikeuchi, Nobuhito; Umeda, Junko; Moriyasu, Fuminori; Tsuchida, Akihiko

    2011-01-01

    AIM: To evaluate the efficacy and safety of endoscopic removal and trimming of self-expandable metallic stents (SEMS). METHODS: All SEMS had been placed for distal biliary strictures. Twenty-seven endoscopic procedures were performed in 19 patients in whom SEMS (one uncovered and 18 covered) removal had been attempted, and 8 patients in whom stent trimming using argon plasma coagulation (APC) had been attempted at Tokyo Medical University Hospital. The APC settings were: voltage 60-80 W and gas flow at 1.5 L/min. RESULTS: The mean stent indwelling period for all patients in whom stent removal had been attempted was 113.7 ± 77.6 d (range, 8-280 d). Of the 19 patients in whom removal of the SEMS had been attempted, the procedure was successful in 14 (73.7%) without procedure-related adverse events. The indwelling period in the stent removable group was shorter than that in the unremovable group (94.9 ± 71.5 d vs 166.2 ± 76.2 d, P = 0.08). Stent trimming was successful for all patients with one minor adverse event consisting of self-limited hemorrhage. Trimming time ranged from 11 to 16 min. CONCLUSION: Although further investigations on larger numbers of cases are necessary to accumulate evidence, the present data suggested that stent removal and stent trimming is feasible and effective for stent-related complications. PMID:21677835

  3. Conformable covered versus uncovered self-expandable metallic stents for palliation of malignant gastroduodenal obstruction: a randomized prospective study.

    PubMed

    Lim, Sun Gyo; Kim, Jin Hong; Lee, Kee Myung; Shin, Sung Jae; Kim, Chan Gyoo; Kim, Kyung Ho; Kim, Ho Gak; Yang, Chang Heon

    2014-07-01

    A conformable self-expandable metallic stent was developed to overcome the limitation of previous self-expandable metallic stents. The aim of this study was to evaluate outcomes after placement of conformable covered and uncovered self-expandable metallic stents for palliation of malignant gastroduodenal obstruction. A single-blind, randomized, parallel-group, prospective study were conducted in 4 medical centres between March 2009 and July 2012. 134 patients with unresectable malignant gastroduodenal obstruction were assigned to a covered double-layered (n=66) or uncovered unfixed-cell braided (n=68) stent placement group. Primary analysis was performed to compare re-intervention rates between two groups. 120 patients were analysed (59 in the covered group and 61 in the uncovered group). Overall rates of re-intervention were not significantly different between the two groups: 13/59 (22.0%) in the covered group vs. 13/61 (21.3%) in the uncovered group, p=0.999. Stent migration was more frequent in the covered group than in the uncovered group (p=0.003). The tumour ingrowth rate was higher in the uncovered group than in the covered group (p=0.016). The rates of re-intervention did not significantly differ between the two stents. Conformable covered double-layered and uncovered unfixed-cell braided stents were associated with different patterns of stent malfunction. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  4. Safety of endoscopic removal of self-expandable stents after treatment of benign esophageal diseases.

    PubMed

    van Halsema, Emo E; Wong Kee Song, Louis M; Baron, Todd H; Siersema, Peter D; Vleggaar, Frank P; Ginsberg, Gregory G; Shah, Pari M; Fleischer, David E; Ratuapli, Shiva K; Fockens, Paul; Dijkgraaf, Marcel G W; Rando, Giacomo; Repici, Alessandro; van Hooft, Jeanin E

    2013-01-01

    Temporary placement of self-expandable stents has been increasingly used for the management of benign esophageal diseases. To evaluate the safety of endoscopic removal of esophageal self-expandable stents placed for the treatment of benign esophageal diseases. Multicenter retrospective study. Six tertiary care centers in the United States and Europe. A total of 214 patients with benign esophageal diseases undergoing endoscopic stent removal. Endoscopic stent removal. Endoscopic techniques for stent removal, time to stent removal, and adverse events related to stent removal. A total of 214 patients underwent a total of 329 stent extractions. Stents were mainly placed for refractory strictures (49.2%) and fistulae (49.8%). Of the removed stents, 52% were fully covered self-expandable metal stents (FCSEMSs), 28.6% were partially covered self-expandable metal stents (PCSEMSs), and 19.5% were self-expandable plastic stents. A total of 35 (10.6%) procedure-related adverse events were reported, including 7 (2.1%) major adverse events. Multivariate analysis revealed that use of PCSEMSs (P < .001) was a risk factor for adverse events during stent removal. Favorable factors for successful stent removal were FCSEMSs (P ≤ .012) and stent migration (P = .010). No significant associations were found for stent indwelling time (P = .145) and stent embedding (P = .194). Retrospective analysis, only tertiary care centers. With an acceptable major adverse event rate of 2.1%, esophageal stent removal in the setting of benign disease was found to be a safe and feasible procedure. FCSEMSs were more successfully removed than self-expandable plastic stents and PCSEMSs. Adverse events caused by stent removal were not time dependent. Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  5. Management of post-gastrectomy anastomosis site obstruction with a self-expandable metallic stent.

    PubMed

    Cha, Ra Ri; Lee, Sang Soo; Kim, Hyunjin; Kim, Hong Jun; Kim, Tae-Hyo; Jung, Woon Tae; Lee, Ok Jae; Bae, Kyung Soo; Jeong, Sang-Ho; Ha, Chang Yoon

    2015-04-28

    Post-gastrectomy anastomosis site obstruction is a relatively rare complication after a subtotal gastrectomy. We present a case of a 75-year-old man who underwent a truncal vagotomy, omental patch, gastrojejunostomy, and Braun anastomosis for duodenal ulcer perforation and a gastric outlet obstruction. Following the 10(th) postoperative day, the patient complained of abdominal discomfort and vomiting. We diagnosed post-gastrectomy anastomosis site obstruction by an upper gastrointestinal series and an upper endoscopic examination. We inserted a self-expandable metallic stent (SEMS) at the anastomosis site. The stent was fully expanded after deployment. On the day following the stent insertion, the patient began to eat, and his abdominal discomfort was resolved. This paper describes the successful management of post-gastrectomy anastomosis site obstruction with temporary placement of a SEMS.

  6. Endoscopic treatment of benign biliary strictures using covered self-expandable metal stents (CSEMS).

    PubMed

    Irani, Shayan; Baron, Todd H; Akbar, Ali; Lin, Otto S; Gluck, Michael; Gan, Ian; Ross, Andrew S; Petersen, Bret T; Topazian, Mark; Kozarek, Richard A

    2014-01-01

    Traditional endoscopic management of benign biliary strictures (BBS) consists of placement of one or more plastic stents. Emerging data support the use of covered self-expandable metal stents (CSEMS). We sought to assess outcome of endoscopic temporary placement of CSEMS in patients with BBS. This was a retrospective study of CSEMS placement for BBS between May 2005 and July 2012 from two tertiary care centers. A total of 145 patients (81 males, median age 59 years) with BBS were identified; 73 of which were classified as extrinsic and were caused by chronic pancreatitis, and 70 were intrinsic. Main outcome measures were resolution of stricture and adverse events (AEs) due to self-expandable metal stents (SEMS)-related therapy. Fully covered and partially covered 8-10 mm diameter SEMS were placed and subsequently removed in 121/125 (97 %) attempts in BBS (failure to remove four partially covered stents). Stricture resolution occurred in 83/125 (66 %) patients after a median stent duration of 26 weeks (median follow-up 90 weeks). Resolution of extrinsic strictures was significantly lower compared to intrinsic strictures (31/65, 48 % vs. 52/60, 87 %, p = 0.004) despite longer median stent duration (30 vs. 20 weeks). Thirty-seven AEs occurred in 25 patients (17 %), with 12 developing multiple AEs including cholangitis (n = 17), pancreatitis (n = 5), proximal stent migration (n = 3), cholecystitis (n = 2), pain requiring SEMS removal and/or hospitalization (n = 3), inability to remove (n = 4), and new stricture formation (n = 3). Benign biliary strictures can be effectively treated with CSEMS. Successful resolution of biliary strictures due to extrinsic disease is seen significantly less often than those due to intrinsic disease. Removal is successful in all patients with fully covered SEMS.

  7. Management of occluded self-expanding biliary metal stents in malignant biliary disease.

    PubMed

    Nennstiel, Simon; Tschurtschenthaler, Isolde; Neu, Bruno; Algül, Hana; Bajbouj, Monther; Schmid, Roland M; von Delius, Stefan; Weber, Andreas

    2018-02-01

    Occlusion of self-expanding metal stents (SEMS) in malignant biliary obstruction occurs in up to 40% of patients. This study aimed to compare the different techniques to resolve stent occlusion in our collective of patients. Patients with malignant biliary obstruction and occlusion of biliary metal stent at a tertiary referral endoscopic center were retrospectively identified between April 1, 1994 and May 31, 2014. The clinical records were further analyzed regarding the characteristics of patients, malignant strictures, SEMS, management strategies, stent patency, subsequent interventions, survival time and case charges. A total of 108 patients with biliary metal stent occlusion were identified. Seventy-nine of these patients were eligible for further analysis. Favored management was plastic stent insertion in 73.4% patients. Second SEMS were inserted in 12.7% patients. Percutaneous transhepatic biliary drainage and mechanical cleansing were conducted in a minority of patients. Further analysis showed no statistically significant difference in median overall secondary stent patency (88 vs. 143 days, P = 0.069), median survival time (95 vs. 192 days, P = 0.116), median subsequent intervention rate (53.4% vs. 40.0%, P = 0.501) and median case charge (€5145 vs. €3473, P = 0.803) for the treatment with a second metal stent insertion compared to plastic stent insertion. In patients with survival time of more than three months, significantly more patients treated with plastic stents needed re-interventions than patients treated with second SEMS (93.3% vs. 57.1%, P = 0.037). In malignant biliary strictures, both plastic and metal stent insertions are feasible strategies for the treatment of occluded SEMS. Our data suggest that in palliative biliary stenting, patients especially those with longer expected survival might benefit from second SEMS insertion. Careful patient selection is important to ensure a proper decision for either management

  8. Endoscopic removal of malfunctioning biliary self-expandable metallic stents.

    PubMed

    Familiari, Pietro; Bulajic, Milutin; Mutignani, Massimiliano; Lee, Linda S; Spera, Gianluca; Spada, Cristiano; Tringali, Andrea; Costamagna, Guido

    2005-12-01

    Endoscopic removal of malfunctioning self-expandable metallic biliary stents (SEMS) is difficult and not well described. The aim of this study is to review the indications, the techniques, and the results of SEMS removal in a cohort of patients with malfunctioning stents. All patients who underwent an attempt at endoscopic removal of biliary SEMS over a 5-year period were retrospectively identified. The main indications for SEMS removal were the following: distal migration of the stent or impaction to the duodenum, impaction into the bile-duct wall, tissue ingrowth, and inappropriate length of the stent causing occlusion of intrahepatic ducts. SEMS were removed by using foreign-body forceps or polypectomy snares. Endoscopic removal of 39 SEMS (13 uncovered and 26 covered) was attempted in 29 patients (17 men; mean age, 66 years). SEMS extraction was attempted after a mean of 7.5 months (8.75 months standard deviation) post-SEMS insertion. Removal was successful in 20 patients (68.9%) and in 29 SEMS (74.3%). Covered SEMS were effectively removed more frequently than uncovered ones: 24 of 26 (92.3%) and 5 of 13 (38.4%), respectively (p < 0.05). No major complications were recorded. Multivariate analysis showed that the time interval between insertion and removal, SEMS length, stent-mesh design (zigzag vs. interlaced), and indication for removal were not predictive of success at stent removal. Endoscopic removal of biliary SEMS is feasible and safe in more than 70% of cases. Because only 38% of uncovered SEMS were removable, the presence of a stent covering is the only factor predictive of successful stent extraction. The presence of diffuse and severe ingrowth was the main feature limiting SEMS removal.

  9. Self-Expanding Metal Stents Improve Swallowing and Maintain Nutrition During Neoadjuvant Therapy for Esophageal Cancer.

    PubMed

    Smith, Zachary L; Gonzaga, Jason E; Haasler, George B; Gore, Elizabeth M; Dua, Kulwinder S

    2017-06-01

    Patients with locally advanced esophageal cancer can have significant dysphagia. Nutritional support during neoadjuvant therapy is often delivered via nasoenteric or percutaneous feeding tubes. These approaches do not allow for per-oral feeding. Evaluate the safety and efficacy of fully covered self-expanding metal esophageal stents for nutritional support during neoadjuvant therapy. This was a pilot, prospective study at a single tertiary center. From March 2012 to May 2013, consecutive patients with esophageal cancer eligible for neoadjuvant therapy were enrolled. Metal stents were placed prior to starting neoadjuvant therapy. Data were collected at baseline and predetermined intervals until an endpoint (surgery or disease progression). Outcomes included dysphagia grade, satisfaction of swallowing score, nutritional status (weight, serum albumin), impact on surgery, and adverse events. Fourteen stents were placed in 12 patients (59.1 ± 9.5 years, 11 men, 1 woman). Dysphagia grade (pre 3.4 ± 0.5 vs post 0.2 ± 0.4, p < 0.0001) and swallowing scores (20.2 ± 5.9 vs 6.3 ± 4.7, p < 0.0001) significantly improved after stent placement. Improvements were sustained throughout neoadjuvant therapy. Body weight and serum albumin levels remained stable. Adverse events included severe chest pain (2), food impaction (1), and delayed stent migration (2). Five patients underwent surgical resection. No significant chemoradiation or operative adverse events occurred due to the presence of a stent. During neoadjuvant therapy for esophageal cancer, self-expanding metal stents are safe and effective in relieving dysphagia and maintaining nutrition. They allow patients to eat orally, thereby improving patient satisfaction. The presence of an in situ stent did not interfere with surgery.

  10. Ex-vivo assessment of anchoring force of covered biflanged metal stent and covered self-expandable metal stent for interventional EUS.

    PubMed

    Tonozuka, Ryosuke; Yunoki, Shunji; Itoi, Takao; Sofuni, Atsushi; Tsuchiya, Takayoshi; Ishii, Kentaro; Tanaka, Reina; Honjo, Mitsuyoshi; Mukai, Shuntaro; Fujita, Mitsuru; Yamamoto, Kenjiro; Asai, Yasutsugu; Matsunami, Yukitoshi; Kurosawa, Takashi; Kojima, Hiroyuki; Nagakawa, Yuichi; Nagakawa, Yoshiyasu

    2018-06-05

    EUS-guided transmural drainage (EUS-TD) using a covered biflanged metal stent (CBFMS) and a conventional tubular biliary covered self-expandable metal stent (CSEMS) has recently been performed by EUS experts. However, appropriate traction force of the sheath to prevent the migration during stent deployment is well unknown. Herein, we assessed the anchoring force (AF) of the distal flange in CBFMSs and CSEMSs. The AFs of 4 CBFMSs (Stents AX, NG, PL, and SX) and 6 CSEMSs (Stents BF, BP, EG, HN, SP, and WF) were compared in an ex vivo setting. We assessed the AF produced by each stent using an EUS-TD model and an EUS-guided hepaticogastrostomy (EUS-HGS) model consisting of sheet-shaped specimens of the stomach, gelatin gel, and gelatin tubes. For CBFMSs, the maximum AF of Stent AX was significantly higher than those of Stents PL and SX (P < 0.05) in the porcine model. In the gelatin series, all stents except Stent NG showed a nearly similar AF. For CSEMSs, Stents HN, EG, BF, and WF showed gradual AF elevation in the porcine stomach. Stents SP and BP showed a lower AF than the other 4 stents. For the gelatin setting, the maximum AF of Stents HN, EG, and WF were higher than those of the other stents regardless of the type of specimens. The significance of the AF and traction distance according to the property of various CBFMSs and CSEMSs could be elucidated using ex-vivo models. This article is protected by copyright. All rights reserved.

  11. Self-Expandable Metallic Stent Placement in Malignant Gastric Outlet Obstruction: A Comparison Between 2 Brands of Stents.

    PubMed

    Ye, Bing-Wei; Lee, Kuei-Chuan; Hsieh, Yun-Cheng; Li, Chung-Pin; Chao, Yee; Hou, Ming-Chih; Lin, Han-Chieh

    2015-07-01

    Malignant gastric outlet obstruction is a late complication of intraabdominal malignancy. Self-expandable metallic stent placement has been a safe palliative treatment to relieve obstructive symptoms. We aimed to assess the efficacy and safety of metallic stents in our patients and analyzed the clinical outcome of different brands. Seventy-one patients with inoperable gastric outlet obstruction receiving WallFlex enteral stents (WallFlex group) or Bonastents (Bonastent group) since April 2010 were analyzed retrospectively. The overall technical and clinical success rates of stent placement were 100% and 93%, respectively. The baseline characteristics and clinical outcomes including procedure-related complications, restenosis, and reintervention rates were comparable between the 2 groups. However, the Bonastent group had a higher rate of stent fracture than the WallFlex group (13.3% vs 0%, P = 0.03). The mean duration of overall stent patency was 132.7 days. The mean duration of survival was 181.9 days. Resumption of regular diet or low residual diet at day 7 after stent insertion predicted stent patency (hazard ratio [HR]: 0.28, P = 0.01). Cancer with gastric origin (HR: 0.25, P = 0.045) and poststent chemotherapy (HR: 0.38, P = 0.006) predicted lower mortality; however, peritoneal carcinomatosis (HR: 3.09, P = 0.04) correlated with higher mortality. Metallic stent placement is a safe and effective method for relieving gastric outlet obstruction. Except higher rate of stent fracture in the Bonastent group, there is no significant difference in clinical outcomes between the Bonastent group and the WallFlex group.

  12. [Trimming with argon plasma of self-expanding metal stents: report of 7 cases].

    PubMed

    Jury, Gastón; Amieva, Leandro; López, Fagalde Rafael; Jury, Rubén

    2014-06-01

    The use of self-expandable enteral stents for palliation of malignant stenosis may present the complication of concealing the ampulla of Vater behind the metallic mesh. Anchoring in the duodenal wall (distal or partial migration) may also be a complication of biliary metallic stents and therefore may cause difficulty in gaining access to the biliary tract. In these cases of difficult access, a fenestration on the prosthesis ( biliary or enteral) can be created to allow reaching the obstructed biliary tract by means of argon plasma (AP). Were retrospectively analysed 7 cases. Under endoscopic vision, AP was directed to filgurate and cut 6 biliary prosthesis and a duodenal stent. Fulguration and cut of biliary stent was performed in 5 cases of distal partial migration and cholangitis. In one case of obstruction caused by distal migration inside the duodenal stent light, cutting of the biliary stent was performed. A window was created in the enteral prosthesis in order to access the ampulla of Vater and place a biliary tract prosthesis. All cases were resolved successfully and without complications. We conclude that the use of AP to fulgurate and cut nitinol prosthesis was effective and presented no complications in this series.

  13. Stent selection for both biliary and pancreatic strictures caused by chronic pancreatitis: multiple plastic stents or metallic stents?

    PubMed

    Gupta, Rajesh; Reddy, D Nageshwar

    2011-09-01

    Endoscopic stenting is an effective treatment option in the management of both benign biliary strictures and pancreatic ductal strictures. Plastic stents and self-expandable metal stents have been used with variable success for the management of both benign biliary strictures and pancreatic ductal strictures caused by chronic pancreatitis. Fully covered self-expandable metal stents of improved design represent a major technological advance which has added to the endoscopic armamentarium. Both multiple plastic stents and covered self-expandable metal stents have shown promising results. However, data to support the use of self-expandable metal stents over multiple plastic stents or vice versa are still lacking.

  14. Self-expandable metallic stents vs. plastic stents for endoscopic biliary drainage in hepatocellular carcinoma.

    PubMed

    Chung, Kwang Hyun; Lee, Sang Hyub; Park, Jin Myung; Lee, Jae Min; Ahn, Dong-Won; Ryu, Ji Kon; Kim, Yong-Tae

    2015-06-01

    The patency of self-expandable metallic stents (SEMS) is known to be better than plastic stents in the palliation of malignant biliary obstruction. However, data are scarce for obstructive jaundice caused by hepatocellular carcinoma (HCC). This study aimed to compare SEMSs and plastic stents for the palliation of obstructive jaundice in unresectable HCC. A total of 96 patients who underwent endoscopic retrograde biliary drainage with SEMSs or plastic stents were included in this retrospective analysis. The rate of successful biliary drainage, adverse events, stent patency duration, and patient survival were compared between the SEMS (n = 36) and plastic stent (n = 60) groups. The rate of successful biliary drainage was similar between the SEMS and plastic stent groups (25/36 [69.4 %] vs. 39/60 [65.0 %]; P = 0.655). Adverse events occurred in 6 patients (16.7 %) in the SEMS group and 13 patients (21.7 %) in the plastic stent group (P = 0.552). The median patency duration was also similar between the two groups (60 vs. 68 days; P = 0.396). The median patient survival was longer in the plastic stent group than in the SEMS group (123 vs. 48 days; P = 0.005). SEMSs were not superior to plastic stents for the palliation of malignant biliary obstruction in HCC with regard to successful drainage, stent patency, and adverse events. Patient survival was better in the plastic stent group. Given the lower cost, plastic stents could be a favorable option for malignant biliary obstruction caused by HCC. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Treatment of benign and malignant tracheobronchial obstruction with metal wire stents: experience with a balloon-expandable and a self-expandable stent type.

    PubMed

    Rieger, Johannes; Hautmann, Hubert; Linsenmaier, Ulrich; Weber, Cristoph; Treitl, Markus; Huber, Rudolf Maria; Pfeifer, Klaus-Jürgen

    2004-01-01

    Over the last few years various types of metal wire stents have been increasingly employed in the treatment of both malignant and benign tracheobronchial obstruction. To date, however, few studies have investigated the in vivo properties of different stent types. We implanted 26 balloon-expandable tantalum Strecker stents (18 patients) and 18 self-expandable Wallstents (16 patients) into the tracheobronchial system of 30 patients with combined stenting in 4 patients. Mean age was 51 years (range: 0.5-79 years). Malignant disease was present in 23 patients, benign disease in seven patients. Both patients and individual stents were monitored clinically and radiographically. The probability of stents remaining within the tracheobronchial system, and of their remaining undislocated and uncompressed was calculated using Kaplan-Meier analysis for both stent types. Average stent follow-up time was 112 days until explantation and 115 days until patients' death or discharge. Kaplan-Meier analysis revealed a higher probability for the Wallstent to remain within the tracheobronchial system. Dislocation and compression occurred more rarely. Explantation, however, if desired, was more difficult compared to the Strecker stent. The Wallstent also led to the formation of granulation tissue, especially at the proximal stent end, frequently requiring reintervention. Both stent types proved to be effective therapeutic options in the management of obstructive tracheobronchial disease. The mechanical properties of the Strecker stent seem to be less favorable compared to the Wallstent but removal is easy. For benign disease, however, the Wallstent reveals limitations due to significant side effects.

  16. Y-shaped bilateral self-expandable metallic stent placement for malignant hilar biliary obstruction: data from a referral center for palliative care.

    PubMed

    Di Mitri, R; Mocciaro, F

    2014-01-01

    Malignant hilar strictures are a clinical challenge because of the current therapeutic approach and the poor prognosis. In recent years, self-expandable metallic stents have proven more effective than plastic stents for palliation of malignant hilar strictures, with the bilateral stent-in-stent technique registering a high success rate. We report our experience with Y-shaped endoscopic self-expandable metallic stents placement for treatment of advanced malignant hilar strictures. From April 2009 to August 2012, we prospectively collected data on patients treated with Y-shaped SEMS placement for advanced malignant hilar carcinoma. Data on technical success, clinical success, and complications were collected. Twenty patients (9 males) were treated (mean age 64.2 ± 15.3 years). The grade of malignant hilar strictures according to the Bismuth classification was II in 5 patients (25%), IIIa in 1 (5%), and IV in 14 (70%). The mean bilirubin level was 14.7 ± 4.9 mg/dL. Technical success was achieved in all patients, with a significant reduction in bilirubin levels (2.9 ± 1.7 mg/dL). One patient experienced cholangitis as early complication, while in 2 patients stent ingrowth was observed. No stents migration was recorded. There was no procedure-related mortality. At the end of the follow-up (7.1 ± 3.1 months), 13 of the 20 patients (65%) had died. Our experience confirms endoscopic bilateral self-expandable metallic stents placement with stent-in-stent technique (Y-shaped configuration) as a feasible, effective, and safe procedure for palliation of unresectable malignant hilar strictures.

  17. Expandable metallic stents for tracheobronchial stenoses in esophageal cancer.

    PubMed

    Takamori, S; Fujita, H; Hayashi, A; Tayama, K; Mitsuoka, M; Ohtsuka, S; Shirouzu, K

    1996-09-01

    Tracheobronchial stenosis in patients with esophageal cancer can be life threatening. Few reports have discussed use of expandable metallic stents for central airway stenoses in patients with esophageal cancer. Twelve patients with esophageal cancer underwent placement of expandable metallic stents for respiratory distress caused by tracheobronchial stricture. Single or double metallic stents were placed in the stenotic airways under fluoroscopic guidance. Improvement in respiratory symptoms and clinical outcome were assessed. Most stenoses were located in the trachea or the left main bronchus. From one to four expandable metallic stents were placed in each stricture site, with immediate relief of respiratory symptoms in 8 patients. One patient with tracheomalacia in alive 3 years after stent placement and another is alive 6 months after stent insertion. The other 10 patients lived from 10 to 70 days (mean; survival, 35 days) after stent placement. Death was due to progression of disease. Although metallic stents are useful for relieving respiratory distress in patients with advanced esophageal cancer, additional therapies should be considered.

  18. Covered versus uncovered self-expandable metal stents for malignant biliary strictures: A meta-analysis and systematic review.

    PubMed

    Moole, Harsha; Bechtold, Matthew L; Cashman, Micheal; Volmar, Fritz H; Dhillon, Sonu; Forcione, David; Taneja, Deepak; Puli, Srinivas R

    2016-09-01

    Self-expandable metal stents (SEMS) are used for palliating inoperable malignant biliary strictures. It is unclear if covered metal stents are superior to uncovered metal stents in these patients. We compared clinical outcomes in patients with covered and uncovered stents. Studies using covered and uncovered metallic stents for palliation in patients with malignant biliary stricture were reviewed. Articles were searched in MEDLINE, PubMed, and Ovid journals. Fixed and random effects models were used to calculate the pooled proportions. Initial search identified 1436 reference articles, of which 132 were selected and reviewed. Thirteen studies (n = 2239) for covered and uncovered metallic stents which met the inclusion criteria were included in this analysis. Odds ratio for stent occlusion rates in covered vs. uncovered stents was 0.79 (95 % CI = 0.65 to 0.96). Survival benefit in patients with covered vs. uncovered stents showed the odds ratio to be 1.29 (95 % CI = 0.95 to 1.74). Pooled odds ratio for migration of covered vs. uncovered stents was 9.9 (95 % CI = 4.5 to 22.3). Covered stents seemed to have significantly lesser occlusion rates, increased odds of migration, and increased odds of pancreatitis compared to uncovered stents. There was no statistically significant difference in the survival benefit, overall adverse event rate, and patency period of covered vs. uncovered metal stents in patients with malignant biliary strictures.

  19. Fully covered self-expanding metal stents versus lumen-apposing fully covered self-expanding metal stent versus plastic stents for endoscopic drainage of pancreatic walled-off necrosis: clinical outcomes and success.

    PubMed

    Siddiqui, Ali A; Kowalski, Thomas E; Loren, David E; Khalid, Ammara; Soomro, Ayesha; Mazhar, Syed M; Isby, Laura; Kahaleh, Michel; Karia, Kunal; Yoo, Joseph; Ofosu, Andrew; Ng, Beverly; Sharaiha, Reem Z

    2017-04-01

    Endoscopic transmural drainage/debridement of pancreatic walled-off necrosis (WON) has been performed using double-pigtail plastic (DP), fully covered self-expanding metal stents (FCSEMSs), or the novel lumen-apposing fully covered self-expanding metal stent (LAMS). Our aim was to perform a retrospective cohort study to compare the clinical outcomes and adverse events of EUS-guided drainage/debridement of WON with DP stents, FCSEMSs, and LAMSs. Consecutive patients in 2 centers with WON managed by EUS-guided debridement were divided into 3 groups: (1) those who underwent debridement using DP stents, (2) debridement using FCSEMSs, (3) debridement using LAMSs. Technical success (ability to access and drain a WON by placement of transmural stents), early adverse events, number of procedures performed per patient to achieve WON resolution, and long-term success (complete resolution of the WON without need for further reintervention at 6 months after treatment) were evaluated. From 2010 to 2015, 313 patients (23.3% female; mean age, 53 years) underwent WON debridement, including 106 who were drained using DP stents, 121 using FCSEMSs, and 86 using LAMSs. The 3 groups were matched for age, cause of the pancreatitis, WON size, and location. The cause of the patients' pancreatitis was gallstones (40.6%), alcohol (30.7%), idiopathic (13.1%), and other causes (15.6%). The mean cyst size was 102 mm (range, 20-510 mm). The mean number of endoscopy sessions was 2.5 (range, 1-13). The technical success rate of stent placement was 99%. Early adverse events were noted in 27 of 313 (8.6%) patients (perforation in 6, bleeding in 8, suprainfection in 9, other in 7). Successful endoscopic therapy was noted in 277 of 313 (89.6%) patients. When comparing the 3 groups, there was no difference in the technical success (P = .37). Early adverse events were significantly lower in the FCSEMS group compared with the DP and LAMS groups (1.6%, 7.5%, and 9.3%; P < .01). At 6-month follow

  20. Pilot study of a novel, large-bore, fully covered self-expandable metallic stent for unresectable distal biliary malignancies.

    PubMed

    Mukai, Tsuyoshi; Yasuda, Ichiro; Isayama, Hiroyuki; Iwashita, Takuji; Itoi, Takao; Kawakami, Hiroshi; Kogure, Hirofumi; Nakai, Yousuke

    2016-09-01

    In patients with unresectable malignant distal biliary obstruction, covered self-expandable metallic stents (CSEMS) may remain patent longer than uncovered self-expandable metallic stents as a result of tumor ingrowth prevention. One main cause of recurrent biliary obstruction (RBO) in CSEMS is sludge formation, which can be prevented using a large-bore stent. Therefore, we developed a novel, 12-mm diameter fully covered SEMS (FCSEMS) and investigated its clinical safety, efficacy, and rate of adverse events. This prospective, multicenter pilot study, which ran between June 2011 and November 2012, included 38 consecutive patients with unresectable malignant distal biliary obstruction. All patients underwent endoscopic insertion of our novel stent. Primary endpoint was non-RBO rate 6 months after placement. Technical and functional success rates of the procedures were 100%. Six-month non-RBO rate was 50%, and median time to RBO was 184 days. Median survival time was 241 days. Twelve patients died within 6 months after stent placement without RBO. RBO was observed in 10 patients (26%), with seven experiencing stent occlusion and three experiencing stent migration. Adverse events other than RBO (at <30 days) developed in six patients (16%; cholecystitis, one; pancreatitis, one; hyperamylasemia, one; pancreatic ductitis, one; abdominal pain, two). Stent removal for reintervention was successfully completed in eight patients. Our novel FCSEMS may be safe and effective for managing malignant distal obstruction with an acceptable incidence of adverse events. © 2016 Japan Gastroenterological Endoscopy Society.

  1. [Clinical application of a fully covered self-expandable metallic stent in treatment of airway fistula].

    PubMed

    Zhu, Qiang; Zang, Qi; Jiang, Zhong-min; Wang, Wei; Cao, Ming

    2013-06-01

    To assess the feasibility, safety and efficacy of the use of a fully covered self-expandable stent for the treatment of airway fistula. From August 2005 to November 2011, 9 patients underwent treatment by the introduction of a tracheo-bronchial or bronchial fully covered self-expandable metallic stent. There were 7 males and 2 females, aged from 28-65 years with a mean of 46 years. In this group, 7 cases were diagnosed as bronchopleural fistula, 1 case as tracheopleural fistula, 1 case as broncho-esophageal fistula, 8 cases with thoracic empyema. The fistula orifices were from 3.5-25.0 mm in diameter with a mean 8.4 mm. All patients received topical anesthesia, and L-shaped stent was placed in 6 patients and I-shaped stent in 3 patients under fluoroscopic guidance. After the stent placement, the patients with empyema were treated with continual irrigation of the empyema cavity. Stent placement in the tracheo-bronchial tree was technically successful in all patients, without procedure-related complications. The operating time was from 5-16 minutes, mean time (10 ± 4) minutes. Except for 1 patient, immediate closure of the airway fistula was achieved in the other patients after the procedure, as shown by the immediate cessation of bubbling in the chest drain system or the contrast examination. In this study, 1 patient coughed the inserted stent out due to irritable cough on the 5th day and had to receive repositioning of a new stent. Among the patients who were with empyema, 1 patient died of septicemia on the 8th day and 1 patient died of brain metastases from lung cancer 6 months after the stent insertion with empyema not cured, the other 6 patients' empyema healed from 2-5 months, mean time 3.7 months. Seven patients were followed from 3 to 36 months with a median of 13.5 months. During follow-up, 1 stent was removed from a patient 8 months after the stent implantation without empyema recurred. The remaining patient presented good tolerability to the existence of

  2. Expandable metal stents for endoscopic bilateral stent-within-stent placement for malignant hilar biliary obstruction.

    PubMed

    Chahal, Prabhleen; Baron, Todd H

    2010-01-01

    Placement of biliary stents is effective for palliation of unresectable hilar malignant biliary obstruction. However, when bilateral self-expandable metal stents (SEMSs) are used, placement can be technically challenging. In many studies, side-by-side placement is performed, although it is unclear whether this is the most anatomical and functional approach. We sought to assess the technical feasibility and effectiveness of deploying bilateral SEMSs with a stent-within-stent approach using commercially available stents with a large cell width. Retrospective study. Tertiary care medical center. Patients with malignant biliary hilar obstruction referred for endoscopic palliation of obstructive jaundice. Technical success, ie, successful bilateral SEMS placement across the stricture; functional success, ie, decrease in pretreatment bilirubin level; early and late complications; and stent patency. Bilateral biliary drainage was attempted and successfully established in 21 patients with malignant hilar obstruction (15 men, 6 women; mean age 63.7 [standard deviation 13.9] years), resulting in clinical improvement of obstructive symptoms. Median follow-up was 6.14 months (interquartile range 3.5-9.5 months). There were 1 (5%) early and 7 (33%) late stent occlusions that required endoscopic reintervention. The 30-day mortality rate was 10% (2 deaths). Retrospective study of a series of cases treated at a tertiary care center by expert endoscopists. This simple technique was performed by using an open-cell expandable metal stent is technically feasible and easy and allows bilateral placement of SEMSs in patients with unresectable hilar malignancy. 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  3. Reintervention for stent occlusion after bilateral self-expandable metallic stent placement for malignant hilar biliary obstruction.

    PubMed

    Inoue, Tadahisa; Naitoh, Itaru; Okumura, Fumihiro; Ozeki, Takanori; Anbe, Kaiki; Iwasaki, Hiroyasu; Nishie, Hirotada; Mizushima, Takashi; Sano, Hitoshi; Nakazawa, Takahiro; Yoneda, Masashi; Joh, Takashi

    2016-11-01

    Endoscopic reintervention for stent occlusions following bilateral self-expandable metallic stent (SEMS) placement for malignant hilar biliary obstruction (MHBO) is challenging, and time to recurrent biliary obstruction (RBO) of the revisionary stent remains unclear. We aimed to clarify a suitable reintervention method for stent occlusions following bilateral SEMS placement for MHBO. Between 2002 and 2014, 52 consecutive patients with MHBO who underwent endoscopic reintervention for stent occlusion after bilateral SEMS placement were enrolled at two university hospitals and one tertiary care referral center. We retrospectively evaluated the technical and functional success rates of the reinterventions, and the time to RBO of the revisionary stents. Technical and functional success rates of the reinterventions were 92% (48/52) and 90% (43/48), respectively. Univariate analysis did not determine any significant predictive factors for technical and functional failures. Median time to RBO of the revisionary stents was 68 days. Median time to RBO was significantly longer for revisionary SEMS placement than for plastic stent placement (131 days vs 47 days, respectively; log-rank test, P = 0.005). Revisionary SEMS placement was the only independent factor that was significantly associated with a longer time to RBO of the revisionary stent in the multivariate Cox proportional hazards analysis (hazard ratio 0.37; 95% confidence interval 0.14-0.95; P = 0.039). Revisionary SEMS placement is a suitable endoscopic reintervention method for stent occlusion following bilateral SEMS placement from the perspective of time to RBO of the revisionary stent. © 2016 Japan Gastroenterological Endoscopy Society.

  4. [Neoplasic colonic obstruction: resolution with self-expanding metallic stents].

    PubMed

    Jury, Gastón; Amieva, Leandro; Dolan, Martín; Fagalde, Rafael López; Naiderman, Diego; Pastorino, Martín; Jury, Rubén

    2014-03-01

    The endoscopic placement of self-expanding metallic stents (SEMS) emerges as a therapeutic option for neoplastic colonic obstruction in two situations: as palliative treatment and as a bridge to surgery. The latter can avoid emergency surgery, thus decreasing the rate of ostomies and the mortality and morbidity associated with them. To evaluate the feasibility, safety and benefits of SEMS placement for the treatment of neoplastic colorectal obstruction. Between August 2008 and June 2012, we included in this prospective, longitudinal, descriptive and observational study all the patients suffering from colorectal neoplasia who were subjected to SEMS placement by the same group ofendoscopists. Nitinol SEMS were inserted under endoscopic vision and radioscopic control. Twenty seven SEMS were inserted in 27 patients, 61% of them were male and the average age was 70 years old. Symptoms of colonic suboclussion or obstruction were found in 92% of patients, 88% of the lesions were located in the left-side colon, 41% of cases were performed on an ambulatory basis and 65% of stenting was carried out for palliative purposes. The average time of hospitalization was 6,46 days. Technical and clinical success were 93% and 100%, respectively. Minor complications were observed in 11% of patients. Colonic stenting was followed by elective surgery within one month, by a laparoscopic technique in most cases. The placement of SEMS arises as a safe and effective alternative to palliative surgery or as a bridge to elective surgery.

  5. Fully covered self-expanding metal stents for refractory anastomotic colorectal strictures.

    PubMed

    Caruso, Angelo; Conigliaro, Rita; Manta, Raffaele; Manno, Mauro; Bertani, Helga; Barbera, Carmelo; Mirante, Vincenzo Giorgio; Frazzoni, Marzio

    2015-05-01

    Some patients with benign colorectal obstruction do not respond to endoscopic balloon dilation. Fully covered self-expandable metal stents (FCSEMSs) have several potential advantages over non-covered stents, including a higher likelihood of retrieval owing to limited local tissue reaction. However, the efficacy and safety of FCSEMSs in benign colorectal strictures have not yet been established. Retrospective analysis of prospectively collected data concerning patients with post-surgical benign symptomatic anastomotic colorectal strictures, refractory to endoscopic dilation and in whom FCSEMSs had been placed at our center. Technical success was defined as successful stent placement and deployment at the stricture site. Early clinical success was defined as symptom relief persisting at least for 3 days. Follow-up was based on monthly clinical evaluation and quarterly endoscopic assessment. Endoscopic stent removal was planned on the basis of clinical or endoscopic assessment. Prolonged clinical success was defined as persistent symptom relief during follow-up. Technical and early clinical success were obtained in 16 of 16 (100%) patients. The median follow-up was 21 months. Prolonged clinical success was achieved in 9/16 (56%) cases. There was no major complication, including perforation and bleeding. Stent migration occurred in 3 (19%) cases, in two of them associated with clinical failure. The median stent diameter was significantly higher in patients with successful than in those with unsuccessful clinical outcome (26 vs. 20 mm, P = 0.006). The clinical success rate was 1/6 (17%) in patients who received a 20-22 mm stent and 8/10 (80%) in those who received a 24-26 mm stent, respectively (P = 0.035). FCSEMSs can represent effective and safe treatment for refractory anastomotic colorectal strictures. Large diameter stents are warranted for better results.

  6. Preoperative biliary decompression preceding pancreaticoduodenectomy with plastic or self-expandable metallic stent.

    PubMed

    Haapamäki, C; Seppänen, H; Udd, M; Juuti, A; Halttunen, J; Kiviluoto, T; Sirén, J; Mustonen, H; Kylänpää, L

    2015-06-01

    The rainage (PBD) prior to pancreaticoduodenectomy (PD) is controversial. If PBD is required, large bore self-expandable metallic stents (SEMS) are thought to maintain better drainage and have fewer postoperative complications than plastic stents. The confirming evidence is scarce. The aim of the study was to compare outcomes of surgery in patients who underwent PBD with SEMS or plastic stents deployed at endoscopic retrograde cholangiopancreatography (ERCP). This is a retrospective study of 366 patients having had PD during 2000-2009. Preceding endoscopic PBD was performed in 191 patients and nine had had percutaneous transhepatic drainage (PTD). At the time of operation, 163 patients had a plastic stent and 28 had SEMS. Due to stent exchanges, 176 plastic stents and 29 SEMS were placed in all. The stent failure rate was 7.4% for plastic stents and 3.4% for SEMS (p = 0.697). A bilirubin level under 50 µmol/L was reached by 80% of the patients with plastic stents and by 61% of the patients with SEMS (p = 0.058). A postoperative infection complication and/or a pancreatic fistula was found in 26% while using plastic stents and in 25% using SEMS (p = 1.000). In unstented patients with biliary obstruction, the bile juice was sterile significantly more often than in endoscopically stented patients (100% vs 1%, p < 0.001). When the stented and unstented patients were compared regarding postoperative infection complications, there was no significant difference between the groups (p = 0.365). Plastic stents did not differ from SEMS regarding the stent failure rate, bilirubin level decrease, amount of bacteria in the bile juice, or postoperative complications when used for PBD. The significantly higher price of SEMS suggests their use in selected cases only. © The Finnish Surgical Society 2014.

  7. Outcomes of second self-expandable metallic stent insertion for malignant gastric outlet obstruction.

    PubMed

    Kim, Chan Gyoo; Choi, Il Ju; Lee, Jong Yeul; Cho, Soo-Jeong; Kim, Soo Jin; Kim, Mi-Jung; Park, Sook Ryun; Park, Young Lee

    2014-01-01

    Self-expandable metallic stents are used widely to relieve malignant gastric outlet obstruction (GOO). However, restenosis or migration of first stents is a frequent complication. The purpose of this retrospective cohort study was to evaluate the effectiveness of second stents as an approach to manage failure of first stents in patients with malignant GOO. A total of 222 patients with gastric cancer received first stents due to inoperable GOO at National Cancer Center in Korea between January 2008 and June 2011. Monthly follow-up interviews were performed, and second stents (stent-in-stent or stent-after-migration) were inserted in 59 patients by June 2012. Technical and clinical successes and long-term complications were evaluated. The technical and immediate clinical success rates were 98.3 % (58/59) and 91.5 % (54/59), respectively. Patients who received a second stent due to late complications involving the first stent (migration, restenosis, and fracture) showed a higher clinical success rate (95.8 % [46/48]) than patients who received a second stent due to immediate clinical failure of the first stent (72.7 % [8/11], p = 0.04). The immediate clinical success rate of stent-after-migration (100 % [11/11]) was not different from that of stent-in-stent (89.6 % [43/48], p = 1.0). The stent dysfunction rate of stent-after-migration (27.3 % [3/11]) also was similar to that of stent-in-stent (29.2 % [14/48], p = 1.0). The median patencies of stent-in-stent and stent-after-migration were 27.4 and 58.4 weeks, respectively (p = 0.177). There were no significant prognostic factors for patency of second stents. Insertion of a second stent is effective for treating the first-stent failure in gastric cancer patients with GOO, especially if the immediate outcome of the first stent was successful.

  8. Fully covered self-expandable metal stent in tracheobronchial disorders: clinical experience.

    PubMed

    Marchese, Roberto; Poidomani, Grazia; Paglino, Giuseppe; Crimi, Claudia; Lo Nigro, Chiara; Argano, Vincenzo

    2015-01-01

    The third-generation fully covered self-expandable metallic stent (SEMS) has been developed to solve the problems of difficult removal and in-stent granuloma formation related to the uncovered or partially covered type. There are few written reports about the performance of this type of stents with early encouraging results. To report and analyse our experience with the Silmet® stent in the management of malignant and benign tracheobronchial disorders. We retrospectively reviewed medical records of patients who underwent fully covered SEMS Silmet placement at the Interventional Pulmonology Unit, La Maddalena Cancer Center, Palermo, Italy, between May 2010 and August 2013. Stents were placed in 52 patients with malignant (n = 49) and benign airway obstruction (n = 2) and broncho-oesophageal fistula (n = 1). SEMSs were inserted into the trachea (n = 19), the main bronchi (n = 21) and the peripheral bronchi (n = 31). Besides 1 procedural dislocation, the deployment was successful in all patients with an immediate significant improvement of symptoms (Barthel Index p < 0.001; Medical Research Council score p < 0.001). A radiographic improvement was detected in 48% of patients. The mean follow-up duration was 119 ± 120 days (range 22-549 days). Complications observed were: migration (7.6%), tumour overgrowth (15%), infections (5.7%), granulation tissue formation (3.8%) and mucus plug (3.8%). The Silmet stent is effective, safe and simple to implant and remove. We suggest its use in cases of tight stenoses, in the treatment of small- to medium-caliber airways or in cases of tortuous airways. © 2015 S. Karger AG, Basel.

  9. [The application of Y-shaped self-expandable covered metal stents in the thoracostomach-airway fistula: a single center, 11 years experience].

    PubMed

    Fang, Yi; Li, Tengfei; Han, Xinwei; Wu, Gang; Ren, Jianzhuang; Ren, Kewei; Lu, Huibin; Zhang, Quanhui; Li, Zongming

    2015-08-01

    To investigate the clinical feasibility and efficacy of Y-shaped self-expandable covered metal stents (Y-stents) in the management of thoracostomach-airway fistula. Retrospective analysis was performed for 108 patients treated for thoracostomach-airway fistula with Y-shaped self-expandable coated metal stents between April 2003 and October 2014. Y-stents were designed based on the dimensions of trachea and bronchus and sites of the fistula and then were inserted under DSA monitoring. There were 65 cases with single big Y-stent placement, 26 cases with single small Y-stent placement, 23 cases with double Y-stents placement, and 1 case with 3 Y-stents placement. Stent implantation was successfully accomplished with single manipulation in all patients. Complete occlusion of the fistula was obtained in 104 patients after the primary manipulation, and 4 patients required a secondary manipulation where a double Y-stents was inserted because of failure of primary manipulate. Ninety-two patients completed the follow-up , while 16 were lost. Fifty-nine patients died while 33 were alive with marked improvement in their quality of life. The placement of Y-stents can effectively occlude the thoracostomach-airway fistula in patients who had had the esophageal tumors resected. The technique is not only feasible but reliable to improve the quality of life of the patients.

  10. Use of covered self-expandable stents for benign colorectal disorders in children.

    PubMed

    Lange, Bettina; Sold, Moritz; Kähler, Georg; Wessel, Lucas M; Kubiak, Rainer

    2017-01-01

    There is a lack of experience with covered self-expandable stents for benign colorectal disorders in children. Five children (4M, 1F) with a median age of 5years (range, 6months-9years) who underwent treatment with covered self-expandable plastic (SEPSs) or self-expandable metal stents (SEMSs) for a benign colorectal condition between April 2005 and November 2013 were recruited to this retrospective study. Etiologies included: anastomotic stricture with (n=1) or without (n=3) simultaneous enterocutaneous fistula, as well as an anastomotic leak associated with enterocutaneous fistula (n=1). All children suffered from either Hirschsprung's disease (n=3) or total colonic aganglionosis (Zuelzer-Wilson syndrome) (n=2). Median duration of individual stent placement was 23days (range, 1-87days). In all cases up to five different stents were placed over time. At follow-up two patients were successfully treated without further intervention. In another patient the anastomotic stricture resolved fully, but a coexisting enterocutaneous fistula persisted. Overall, three patients did not improve completely following stenting and required definite surgery. Stent-related problems were noted in all cases. There was one perforation of the colon at stent insertion. Further complications consisted of stent dislocation (n=4), obstruction (n=1), formation of granulation tissue (n=1), ulceration (n=1) and discomfort (n=3). Covered self-expandable stents enrich the armamentarium of interventions for benign colorectal disorders in children including anastomotic strictures and intestinal leaks. A stent can be applied either as an emergency procedure (bridge to surgery) or as an adjuvant treatment further to endoscopy and dilatation. Postinterventional problems are frequent but there is a potential for temporary or definite improvement following stent insertion. Copyright © 2017. Published by Elsevier Inc.

  11. [A Case of Removable Self-Expandable Metallic Stent(SEMS)Placement for Gastric Tube Stenosis after Esophageal Cancer Resection].

    PubMed

    Yoshikawa, Yukihiro; Yoshikawa, Masato; Kawabata, Ryohei; Yoshida, Yuta; Kawada, Masahiro; Yasuyama, Akinobu; Watase, Chikashi; Koga, Chikato; Hitora, Toshiki; Murakami, Masahiro; Hirota, Masaki; Ikenaga, Masakazu; Shimizu, Junzo; Hasegawa, Junichi

    2015-11-01

    A 68-year-old man underwent esophagectomy for early esophageal cancer. Postoperative upper gastrointestinal series and esophagogastroduodenoscopy showed gastric tube stenosis. To improve passage, a removable self-expandable metallic stent (SEMS) was placed across the stenotic lesion. Two weeks later, the stent was removed, and passage through the gastric tube improved. The patient has no symptoms of stenosis. A removable SEMS could be an option for the treatment of gastric tube stenosis after esophagectomy.

  12. Single brand, fully-covered, self-expandable metal stent for the treatment of benign biliary disease: when should stents be removed?

    PubMed

    Mangiavillano, Benedetto; Khashab, Mouen A; Eusebi, Leonardo H; Tarantino, Ilaria; Bianchetti, Mario; Semeraro, Rossella; Pellicano, Rinaldo; Traina, Mario; Repici, Alessandro

    2018-05-31

    The two most relevant endoscopic treatable benign biliary diseases (BBD) are benign biliary strictures (BBSs) and biliary leaks (BLs), often associated with high morbidity. The most common endoscopic treatment for biliary strictures involves placement of multiple plastic stents (PSs), with or without balloon dilation, followed by planned exchange of the stents. Thus, there continues to be high interest in pursuing alternative endoscopic approaches that may achieve better results with fewer interventions. In this setting, the use of a fully-covered, self-expandable metal stent (FCSEMS) is an attractive alternative to single or multiple PSs for the treatment of BBDs. A single metal stent can remain in place for a longer period of time before removal; however, the maximum time the stent can be remain in place is still not well defined. The aim of this review is to determine the removal time of the TaeWoong® FCSEMS, placed for BBD. According to our data analysis, considering the absence of loss of the covering of the FCSEMS and of any adverse events during and after stent removal, leaving the TaeWoong medical FCSEMS in situ for an 8 months' period seems to be acceptable for benign biliary diseases. Further studies need to evaluate their removability at 1 year.

  13. Comparison between uncovered and covered self-expandable metal stent placement in malignant duodenal obstruction.

    PubMed

    Kim, Ji Won; Jeong, Ji Bong; Lee, Kook Lae; Kim, Byeong Gwan; Ahn, Dong Won; Lee, Jae Kyung; Kim, Su Hwan

    2015-02-07

    To compare the clinical outcomes of uncovered and covered self-expandable metal stent placements in patients with malignant duodenal obstruction. A total of 67 patients were retrospectively enrolled from January 2003 to June 2013. All patients had symptomatic obstruction characterized by nausea, vomiting, reduced oral intake, and weight loss. The exclusion criteria included asymptomatic duodenal obstruction, perforation or peritonitis, concomitant small bowel obstruction, or duodenal obstruction caused by benign strictures. The technical and clinical success rate, complication rate, and stent patency were compared according to the placement of uncovered (n = 38) or covered (n = 29) stents. The technical and clinical success rates did not differ between the uncovered and covered stent groups (100% vs 96.6% and 89.5% vs 82.8%). There were no differences in the overall complication rates between the uncovered and covered stent groups (31.6% vs 41.4%). However, stent migration occurred more frequently with covered than uncovered stents [20.7% (6/29) vs 0% (0/38), P < 0.05]. Moreover, the overall cumulative median duration of stent patency was longer in uncovered than in covered stents [251 d (95%CI: 149.8 d-352.2 d) vs 139 d (95%CI: 45.5 d-232.5 d), P < 0.05 by log-rank test] The overall cumulative median survival period was not different between the uncovered stent (70 d) and covered stent groups (60 d). Uncovered stents may be preferable in malignant duodenal obstruction because of their greater resistance to stent migration and longer stent patency than covered stents.

  14. Comparison between uncovered and covered self-expandable metal stent placement in malignant duodenal obstruction

    PubMed Central

    Kim, Ji Won; Jeong, Ji Bong; Lee, Kook Lae; Kim, Byeong Gwan; Ahn, Dong Won; Lee, Jae Kyung; Kim, Su Hwan

    2015-01-01

    AIM: To compare the clinical outcomes of uncovered and covered self-expandable metal stent placements in patients with malignant duodenal obstruction. METHODS: A total of 67 patients were retrospectively enrolled from January 2003 to June 2013. All patients had symptomatic obstruction characterized by nausea, vomiting, reduced oral intake, and weight loss. The exclusion criteria included asymptomatic duodenal obstruction, perforation or peritonitis, concomitant small bowel obstruction, or duodenal obstruction caused by benign strictures. The technical and clinical success rate, complication rate, and stent patency were compared according to the placement of uncovered (n = 38) or covered (n = 29) stents. RESULTS: The technical and clinical success rates did not differ between the uncovered and covered stent groups (100% vs 96.6% and 89.5% vs 82.8%). There were no differences in the overall complication rates between the uncovered and covered stent groups (31.6% vs 41.4%). However, stent migration occurred more frequently with covered than uncovered stents [20.7% (6/29) vs 0% (0/38), P < 0.05]. Moreover, the overall cumulative median duration of stent patency was longer in uncovered than in covered stents [251 d (95%CI: 149.8 d-352.2 d) vs 139 d (95%CI: 45.5 d-232.5 d), P < 0.05 by log-rank test] The overall cumulative median survival period was not different between the uncovered stent (70 d) and covered stent groups (60 d). CONCLUSION: Uncovered stents may be preferable in malignant duodenal obstruction because of their greater resistance to stent migration and longer stent patency than covered stents. PMID:25663777

  15. Predictive factors for the failure of endoscopic stent-in-stent self-expandable metallic stent placement to treat malignant hilar biliary obstruction.

    PubMed

    Sugimoto, Mitsuru; Takagi, Tadayuki; Suzuki, Rei; Konno, Naoki; Asama, Hiroyuki; Watanabe, Ko; Nakamura, Jun; Kikuchi, Hitomi; Waragai, Yuichi; Takasumi, Mika; Sato, Yuki; Hikichi, Takuto; Ohira, Hiromasa

    2017-09-14

    To investigate the factors predictive of failure when placing a second biliary self-expandable metallic stents (SEMSs). This study evaluated 65 patients with an unresectable malignant hilar biliary obstruction who were examined in our hospital. Sixty-two of these patients were recruited to the study and divided into two groups: the success group, which consisted of patients in whom a stent-in-stent SEMS had been placed successfully, and the failure group, which consisted of patients in whom the stent-in-stent SEMS had not been placed successfully. We compared the characteristics of the patients, the stricture state of their biliary ducts, and the implemented endoscopic retrograde cholangiopancreatography (ERCP) procedures between the two groups. The angle between the target biliary duct stricture and the first implanted SEMS was significantly larger in the failure group than in the success group. There were significantly fewer wire or dilation devices (ERCP catheter, dilator, or balloon catheter) passing the first SEMS cell in the failure group than in the success group. The cut-off value of the angle predicting stent-in-stent SEMS placement failure was 49.7 degrees according to the ROC curve (sensitivity 91.7%, specificity 61.2%). Furthermore, the angle was significantly smaller in patients with wire or dilation devices passing the first SEMS cell than in patients without wire or dilation devices passing the first SEMS cell. A large angle was identified as a predictive factor for failure of stent-in-stent SEMS placement.

  16. Expandable stents.

    PubMed

    Nesbitt, J C; Carrasco, H

    1996-05-01

    Expandable metallic stents are effective in selected patients with malignant or benign airway stenoses. When used for malignant lesions, the primary purpose of the stent is to improve the quality of life; stents are usually chosen for palliation of symptoms in recognition of the low likelihood of success for other therapy. For patients with benign stenoses, the stents provide a permanent source of structural support to alleviate the narrowed segment. The advantages of the expandable metallic stents are as follows: (1) they can be inserted through an endotracheal tube or under local anesthesia with relative simplicity under fluoroscopic guidance; (2) they do not impair the drainage of sputum because ciliary movement is not interrupted; (3) over a period of a few weeks, the meshwork is gradually covered with mucosa as the stent becomes incorporated into the airway wall; (4) ventilation usually is not impaired if the metallic mesh stent covers another nonstenosed bronchus, because the interstices of the stent are nonobstructive; and (5) they are dynamic and continue to expand over time, particularly if concurrent treatment achieves an effect on the lesion that caused stenosis. Disadvantages of the expandable stent include (1) they often are only temporarily effective for tracheobronchial stenosis due to intraluminal tumor or granulation tissue, both of which can grow between the wires; (2) they are considered permanent stents because removal is difficult; and (3) they can be poorly positioned during placement or can become displaced by progressive migration after placement, and they cannot be repositioned. A relative contraindication to insertion is an inflammatory process or infection that can predispose to granulation formation, particularly at the points of maximal contact pressure of the stent to the airway mucosa. In the presence of inflammation, it may be better to use a silicone prosthesis until the inflammatory process subsides and fibrosis occurs. Granulation

  17. Endoscopic removal of laser-cut covered self-expandable metallic biliary stents: A report of six cases.

    PubMed

    Tanisaka, Yuki; Ryozawa, Shomei; Kobayashi, Masanori; Harada, Maiko; Kobatake, Tsutomu; Omiya, Kumiko; Iwano, Hirotoshi; Arai, Shin; Nonaka, Kouichi; Mashimo, Yumi

    2018-02-01

    Covered self-expandable metallic stents (CSEMS) may provide palliative drainage for unresectable distal malignant biliary strictures. Laser-cut CSEMS allows easy positioning due to its characteristic of minimal stent shortening. Endoscopic stent removal is sometimes recommended for recurrent biliary obstruction (RBO). However, there are no previous reports of endoscopic removal of laser-cut CSEMS. The current study presents data from 6 patients who were placed a laser-cut CSEMS for unresectable distal malignant biliary strictures, and later endoscopic stent removal was attempted for RBO at the present institute. The duration of stent placement, the procedural success rate, the procedural duration, and accidental complications were evaluated. The mean duration of stent placement was 156±37.9 days (range, 117-205). The procedural success rate was 100%. The mean procedural duration was 11.8±7.5 min (range, 5-24). No complications were reported. Laser-cut CSEMS were safely removed from all patients. The present case report is the first to demonstrate that Endoscopic stent removal of laser-cut CSEMS was safely performed.

  18. Understanding the Mechanical forces of Self-Expandable Metal Stents in the Biliary Ducts.

    PubMed

    Isayama, Hiroyuki; Nakai, Yousuke; Hamada, Tsuyoshi; Matsubara, Saburo; Kogure, Hirofumi; Koike, Kazuhiko

    2016-12-01

    Self-expandable metallic stent (SEMS) was an effective biliary endoprosthesis. Mechanical properties of SEMS, radial and axial force (RF, AF), may play important roles in the bile duct after placement. RF was well known dilation force and influenced on the occurrence of migration. AF, newly proposed by this author, was defined as the recovery force when the SEMS vended. AF was related with the cause of bile duct kinking, pancreatitis, and cholecystitis due to the compression of the bile duct, orifice of the cystic duct, and pancreatic orifice. Ideal SEMS may show high RF and low AF.

  19. Management of stent dislodgment in coarctoplasty of aorta with three overlapping self-expandable nitinol stents.

    PubMed

    Ghazi, Payam; Haji-Zeinali, Ali-Mohammad

    2010-01-01

    We describe a case of native coarctation of aorta managed with three self-expandable nitinol stents. After balloon pre-dilation, the first and second stents were dislodged. The coarcted area was successfully treated with the third stent overlapped with the previous stents. During follow up (30 months), the patient was free of complications. It seems that implantation of multiple overlapping self-expandable stents in aortic coarctation patients, if needed, is safe and possible.

  20. Fully covered self-expanding metallic stent placement for benign refractory esophageal strictures.

    PubMed

    Kahalekar, Vinit; Gupta, Deepak Trilokinath; Bhatt, Pratin; Shukla, Akash; Bhatia, Shobna

    2017-05-01

    Treatment options for benign refractory esophageal stricture are limited. We retrospectively analyzed data of 11 patients who underwent fully covered self-expanding metallic stent (FC-SEMS) placement for refractory benign esophageal stricture at our institute. Refractory benign esophageal stricture was defined as inability to dilate a stricture to a diameter of 14 mm after a minimum of five sessions at 2-week intervals or inability to maintain diameter of 14 mm for at least 4 weeks. Eleven patients with refractory benign esophageal stricture (corrosive-6, peptic-3, and post-sclerotherapy-2) underwent FC-SEMS placement. The stent was removed after 4-6 weeks as per manufacturer's recommendation. Patients were followed up for 1 year. Three patients with peptic strictures [length of stricture 2, 3, and 3 cm] and two patients with post-sclerotherapy stricture [length 2 and 1.5 cm] had complete response. Two of 6 patients with corrosive stricture (10 cm, 12 cm) developed recurrence of symptoms within 1 month of stent removal, and two after 2 months (8 cm, 3 cm). One patient with corrosive stricture (6 cm) had recurrence after 6 months, and responded to single session of dilatation. One patient with corrosive stricture was asymptomatic for last 12 months. Four stents were migrated. Four patients developed severe retrosternal pain following stent placement, which was managed with analgesics. There were no serious adverse events after placement of stent and removal of stent. Fully covered SEMS is safe and effective for refractory benign non-corrosive esophageal strictures.

  1. Efficacy of endoscopic management of leak after foregut surgery with endoscopic covered self-expanding metal stents (SEMS).

    PubMed

    Aryaie, Amir H; Singer, Jordan L; Fayezizadeh, Mojtaba; Lash, Jon; Marks, Jeffrey M

    2017-02-01

    Anastomotic or staple-line leak after foregut surgery presents a formidable management challenge. In recent years, with advancement of endoscopy, self-expanding covered stents have been gaining popularity. In this study, we aimed to determine the safety and effectiveness of self-expanding covered stents in management of leak after foregut surgery. Consecutive patients who received a fully covered self-expandable metal stent (SEMS) due to an anastomotic leak after upper gastrointestinal surgery between 2009 and 2014 were retrospectively reviewed. Demographic data, stent placement and removal, clinical success, time to resolution, and complications were collected. Predictive factors for clinical success rate were assessed. A total of 20 consecutive patients underwent placement of fully covered SEMS for anastomotic leak, following esophagectomy (n = 5), esophageal diverticulectomy (n = 1), gastric sleeve (n = 4), gastric bypass (n = 3), partial gastrectomy (n = 4), and total gastrectomy (n = 3). All the stents were removed successfully, and clinical resolution was achieved in 18 patients (90 %) after a median of two (range 1-3) procedures and a mean of 6.2 weeks (range 0.4-14). Complications presented in 12 patients (60 %), including stent migration (n = 8), mucosal friability (n = 4), tissue integration (n = 2), and bleeding (n = 2). Two (10 %) patients' treatment was complicated by aorto-esophageal fistula formation resulting in one death. Demographic factors, comorbidities, and type of surgery were not predictive of clinical success rate or time to resolution. SEMS are effective tools for the management of leaks after foregut surgery. The biggest challenge with this approach is stent migration. Caution is warranted due to the risk of fatal complications such as aorto-esophageal fistula formation. No type of surgery or particular patient factor, including age, sex, BMI, albumin, history of radiation, malignancy, and comorbid diabetes or

  2. How to design the optimal self-expandable oesophageal metallic stents: 22 years of experience in 645 patients with malignant strictures.

    PubMed

    Na, Han Kyu; Song, Ho-Young; Kim, Jin Hyoung; Park, Jung-Hoon; Kang, Min Kyoung; Lee, Jongjin; Oh, Se Jin

    2013-03-01

    To evaluate the clinical efficacy and safety of self-expandable metallic stent (SEMS) placement for malignant oesophageal strictures and their relationship with stent designs. Seven generations of SEMS were used to treat 645 consecutive patients with oesophageal strictures. Logistic regression models were constructed to identify predictive factors associated with complications. Stent placement was technically successful in 641 of 645 patients (99.4%). The clinical success rate was 95.5%. There were 260 (40.3%) complications after stent placement. Due to complications, 68 stents were removed; 66 of 68 stents (97.1%) were removed successfully. Stainless steel (SS) stents (odds ratio [OR] 4.18; 95% confidence interval [CI] 2.10, 8.32) and radiation therapy (RT) before stent placement (OR 4.23; CI 2.02, 8.83) were significantly associated with severe pain. Flared ends (OR 9.63; CI 3.38, 27.43), stricture length <6 cm (OR 2.01; CI 1.13, 3.60), and a stent diameter <18 mm (OR 3.00; CI 1.32, 6.84) were predictive factors of stent migration. Polyurethane membranes were associated with more frequent tumour ingrowth than polytetrafluoroethylene (PTFE) membranes (P = 0.002). Despite the relatively high complication rate, retrievable self-expandable PTFE-covered nitinol stents equipped with a head and a tail appeared to be an effective treatment for malignant oesophageal strictures.

  3. Self-expandable metallic stent placement plus laparoscopy for acute malignant colorectal obstruction.

    PubMed

    Zhou, Jia-Min; Yao, Li-Qing; Xu, Jian-Min; Xu, Mei-Dong; Zhou, Ping-Hong; Chen, Wei-Feng; Shi, Qiang; Ren, Zhong; Chen, Tao; Zhong, Yun-Shi

    2013-09-07

    To investigate the clinical advantages of the stent-laparoscopy approach to treat colorectal cancer (CRC) patients with acute colorectal obstruction (ACO). From April 2008 to April 2012, surgery-related parameters, complications, overall survival (OS), and disease-free survival (DFS) of 74 consecutive patients with left-sided CRC presented with ACO who underwent self-expandable metallic stent (SEMS) placement followed by one-stage open (n = 58) or laparoscopic resection (n = 16) were evaluated retrospectively. The stent-laparoscopy group was also compared with a control group of 96 CRC patients who underwent regular laparoscopy without ACO between January 2010 and December 2011 to explore whether SEMS placement influenced the laparoscopic procedure or reduced long-term survival by influencing CRC oncological characteristics. The characteristics of patients among these groups were comparable. The rate of conversion to open surgery was 12.5% in the stent-laparoscopy group. Bowel function recovery and postoperative hospital stay were significantly shorter (3.3 ± 0.9 d vs 4.2 ± 1.5 d and 6.7 ± 1.1 d vs 9.5 ± 6.7 d, P = 0.016 and P = 0.005), and surgical time was significantly longer (152.1 ± 44.4 min vs 127.4 ± 38.4 min, P = 0.045) in the stent-laparoscopy group than in the stent-open group. Surgery-related complications and the rate of admission to the intensive care unit were lower in the stent-laparoscopy group. There were no significant differences in the interval between stenting and surgery, intraoperative blood loss, OS, and DFS between the two stent groups. Compared with those in the stent-laparoscopy group, all surgery-related parameters, complications, OS, and DFS in the control group were comparable. The stent-laparoscopy approach is a feasible, rapid, and minimally invasive option for patients with ACO caused by left-sided CRC and can achieve a favorable long-term prognosis.

  4. Self-expanding metal stents for treatment of anastomotic complications after colorectal resection.

    PubMed

    Lamazza, A; Fiori, E; De Masi, E; Scoglio, D; Sterpetti, A V; Lezoche, E

    2013-06-01

    Self-expanding metal stents (SEMS) can be used to treat patients with symptomatic anastomotic complications after colorectal resection. In the present case series, 16 patients with symptomatic anastomotic stricture after colorectal resection were treated with endoscopic placement of SEMS. Seven patients had a "simple" anastomotic stricture and nine patients had a fistula associated with the stricture. The anastomotic fistula healed without evidence of residual stricture or major fecal incontinence in seven of the nine patients. Overall the anastomotic stricture was resolved in 10 of the 16 patients. SEMS placement represents a valid adjunctive to treatment in patients with symptomatic anastomotic complications after colorectal resection for cancer. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Predictive factors for the failure of endoscopic stent-in-stent self-expandable metallic stent placement to treat malignant hilar biliary obstruction

    PubMed Central

    Sugimoto, Mitsuru; Takagi, Tadayuki; Suzuki, Rei; Konno, Naoki; Asama, Hiroyuki; Watanabe, Ko; Nakamura, Jun; Kikuchi, Hitomi; Waragai, Yuichi; Takasumi, Mika; Sato, Yuki; Hikichi, Takuto; Ohira, Hiromasa

    2017-01-01

    AIM To investigate the factors predictive of failure when placing a second biliary self-expandable metallic stents (SEMSs). METHODS This study evaluated 65 patients with an unresectable malignant hilar biliary obstruction who were examined in our hospital. Sixty-two of these patients were recruited to the study and divided into two groups: the success group, which consisted of patients in whom a stent-in-stent SEMS had been placed successfully, and the failure group, which consisted of patients in whom the stent-in-stent SEMS had not been placed successfully. We compared the characteristics of the patients, the stricture state of their biliary ducts, and the implemented endoscopic retrograde cholangiopancreatography (ERCP) procedures between the two groups. RESULTS The angle between the target biliary duct stricture and the first implanted SEMS was significantly larger in the failure group than in the success group. There were significantly fewer wire or dilation devices (ERCP catheter, dilator, or balloon catheter) passing the first SEMS cell in the failure group than in the success group. The cut-off value of the angle predicting stent-in-stent SEMS placement failure was 49.7 degrees according to the ROC curve (sensitivity 91.7%, specificity 61.2%). Furthermore, the angle was significantly smaller in patients with wire or dilation devices passing the first SEMS cell than in patients without wire or dilation devices passing the first SEMS cell. CONCLUSION A large angle was identified as a predictive factor for failure of stent-in-stent SEMS placement. PMID:28974893

  6. Covered versus Uncovered Self-Expandable Metal Stents for Managing Malignant Distal Biliary Obstruction: A Meta-Analysis.

    PubMed

    Li, Jinjin; Li, Tong; Sun, Ping; Yu, Qihong; Wang, Kun; Chang, Weilong; Song, Zifang; Zheng, Qichang

    2016-01-01

    To compare the efficacy of using covered self-expandable metal stents (CSEMSs) and uncovered self-expandable metal stents (UCSEMSs) to treat objective jaundice caused by an unresectable malignant tumor. We performed a comprehensive electronic search from 1980 to May 2015. All randomized controlled trials comparing the use of CSEMSs and UCSEMSs to treat malignant distal biliary obstruction were included. The analysis included 1417 patients enrolled in 14 trials. We did not detect significant differences between the UCSEMS group and the CSEMS group in terms of cumulative stent patency (hazard ratio (HR) 0.93, 95% confidence interval (CI) 0.19-4.53; p = 0.93, I2 = 0%), patient survival (HR 0.77, 95% CI 0.05-10.87; p = 0.85, I2 = 0%), overall stent dysfunction (relative ratio (RR) 0.85, M-H, random, 95% CI 0.57-1.25; p = 0.83, I2 = 63%), the overall complication rate (RR 1.26, M-H, fixed, 95% CI 0.94-1.68; p = 0.12, I2 = 0%) or the change in serum bilirubin (weighted mean difference (WMD) -0.13, IV fixed, 95% CI 0.56-0.3; p = 0.55, I2 = 0%). However, we did detect a significant difference in the main causes of stent dysfunction between the two groups. In particular, the CSEMS group exhibited a lower rate of tumor ingrowth (RR 0.25, M-H, random, 95% CI 0.12-0.52; p = 0.002, I2 = 40%) but a higher rate of tumor overgrowth (RR 1.76, M-H, fixed, 95% CI 1.03-3.02; p = 0.04, I2 = 0%). Patients with CSEMSs also exhibited a higher migration rate (RR 9.33, M-H, fixed, 95% CI 2.54-34.24; p = 0.008, I2 = 0%) and a higher rate of sludge formation (RR 2.47, M-H, fixed, 95% CI 1.36-4.50; p = 0.003, I2 = 0%). Our meta-analysis indicates that there is no significant difference in primary stent patency and stent dysfunction between CSEMSs and UCSEMSs during the period from primary stent insertion to primary stent dysfunction or patient death. However, when taking further management for occluded stents into consideration, CSEMSs is a better choice for patients with malignant biliary

  7. Covered versus Uncovered Self-Expandable Metal Stents for Managing Malignant Distal Biliary Obstruction: A Meta-Analysis

    PubMed Central

    Sun, Ping; Yu, Qihong; Wang, Kun; Chang, Weilong; Song, Zifang; Zheng, Qichang

    2016-01-01

    Aim To compare the efficacy of using covered self-expandable metal stents (CSEMSs) and uncovered self-expandable metal stents (UCSEMSs) to treat objective jaundice caused by an unresectable malignant tumor. Methods We performed a comprehensive electronic search from 1980 to May 2015. All randomized controlled trials comparing the use of CSEMSs and UCSEMSs to treat malignant distal biliary obstruction were included. Results The analysis included 1417 patients enrolled in 14 trials. We did not detect significant differences between the UCSEMS group and the CSEMS group in terms of cumulative stent patency (hazard ratio (HR) 0.93, 95% confidence interval (CI) 0.19–4.53; p = 0.93, I2 = 0%), patient survival (HR 0.77, 95% CI 0.05–10.87; p = 0.85, I2 = 0%), overall stent dysfunction (relative ratio (RR) 0.85, M-H, random, 95% CI 0.57–1.25; p = 0.83, I2 = 63%), the overall complication rate (RR 1.26, M-H, fixed, 95% CI 0.94–1.68; p = 0.12, I2 = 0%) or the change in serum bilirubin (weighted mean difference (WMD) -0.13, IV fixed, 95% CI 0.56–0.3; p = 0.55, I2 = 0%). However, we did detect a significant difference in the main causes of stent dysfunction between the two groups. In particular, the CSEMS group exhibited a lower rate of tumor ingrowth (RR 0.25, M-H, random, 95% CI 0.12–0.52; p = 0.002, I2 = 40%) but a higher rate of tumor overgrowth (RR 1.76, M-H, fixed, 95% CI 1.03–3.02; p = 0.04, I2 = 0%). Patients with CSEMSs also exhibited a higher migration rate (RR 9.33, M-H, fixed, 95% CI 2.54–34.24; p = 0.008, I2 = 0%) and a higher rate of sludge formation (RR 2.47, M-H, fixed, 95% CI 1.36–4.50; p = 0.003, I2 = 0%). Conclusions Our meta-analysis indicates that there is no significant difference in primary stent patency and stent dysfunction between CSEMSs and UCSEMSs during the period from primary stent insertion to primary stent dysfunction or patient death. However, when taking further management for occluded stents into consideration, CSEMSs is a

  8. Tracheal Self-Expandable Metallic Stents: A Comparative Study of Three Different Stents in a Rabbit Model.

    PubMed

    Serrano, Carolina; Lostalé, Fernando; Rodríguez-Panadero, Francisco; Blas, Ignacio de; Laborda, Alicia; de Gregorio, Miguel Angel

    2016-03-01

    The objective of this study was to assess tracheal reactivity after the deployment of different self-expandable metal stents (SEMS). Forty female New Zealand rabbits were divided into four groups. Three groups received three different SEMS: steel (ST), nitinol (NiTi), or nitinol drug-eluting stent (DES); the fourth group was the control group (no stent). Stents were deployed percutaneously under fluoroscopic guidance. Animals were assessed by multi-slice, computed tomography (CT) scans, and tracheas were collected for anatomical pathology (AP) study. Data from CT and AP were statistically analyzed and correlated. The DES group had the longest stenosis (20.51±14.08mm vs. 5.84±12.43 and 6.57±6.54mm in NiTi and ST, respectively, day 30; P<.05), and higher granuloma formation on CT (50% of cases). The NiTi group showed the lowest grade of stenosis (2.86±6.91% vs. 11.28±13.98 and 15.54±25.95% in DES and ST, respectively; P<.05). The AP study revealed that the ST group developed intense proliferative reactivity compared to the other groups. In the DES group, a destructive response was observed in 70% of the animals, while the NiTi was the least reactive stent. CT was more effective in detecting wall thickening (positive correlation of 68.9%; P<.001) than granuloma (not significant). The ST group developed granulomas and significant stenosis. NiTi was the least reactive stent, while DES caused significant lesions that may be related to drug dosage. This type of DES stent is therefore not recommended for the treatment of tracheobronchial stenosis. Copyright © 2015 SEPAR. Published by Elsevier Espana. All rights reserved.

  9. [Membrane-covered self-expanding stents in the treatment of high-positioned esophageal stenosis or fistula].

    PubMed

    Liu, Jing-zheng; Zhong, Yun-shi; Xu, Mei-dong; Chen, Wei-feng; Zhou, Ping-hong; Yao, Li-qing

    2013-12-01

    To investigate the efficacy and safety of membrane-covered self-expanding metal stent in the treatment of high-positioned esophageal diseases, including esophageal stenosis, esophagotracheal fistula and anastomotic stricture. Clinical data of 84 patients who underwent stenting in our center from May 2005 to July 2013 were retrospectively analyzed. Of 84 patients, 31 were diagnosed as esophageal malignant stenosis, 2 compression stenosis, 10 radiation stenosis, 4 recurrent malignant stenosis, 27 anastomotic stricture, 1 esophageal stenosis after endoscopic submucosal dissection (ESD), 7 esophageal-tracheal fistula, 1 esophageal-mediastinal fistula, and 1 remnant stomach fistula. Distance from stenosis or fistula to central incisor was 15-20 cm in 48 cases, and more than 20 cm in 36 cases. All the patients were treated by 16 mm membrane-covered self-expanding metal stents. Main clinical manifestations and complications were evaluated. A total of 100 stents were placed in 84 patients,with a success rate of 100%. There were no complications such as perforation and bleeding during operation. Dysphagia and cough were improved quickly with a success rate of 100%. After the placement of stents, the incidence of complication was 6.0% (5/84), of which 2 cases were severe retrosternal pain, 1 was tracheal collapse, and 2 were stent displacement. Seventy-six patients (90.5%) received complete follow-up of 1 to 36 months (mean 15 months). Re-stenosis occurred in 4 cases, new esophageal-tracheal fistula in 2 cases. Among these 6 cases, 5 cases underwent successfully stent placement once again, and another one case received Savary bougie and Argon-ion coagulation with good efficacy. Endoscopic membrane-covered self-expanding metal stent placement is effective and safe for the relieve of dysphagia symptoms and the sealing of esophagotracheal fistula.

  10. Management of benign biliary strictures with a novel retrievable self-expandable metal stent.

    PubMed

    Hu, Bing; Leung, Joseph W; Gao, Dao Jian; Wang, Tian Tian; Wu, Jun

    2014-03-01

    Endoscopic placement of covered self-expandable metal stent (SEMS) has gained popularity in the management of benign biliary strictures (BBS). The existing SEMS has been designed primarily to palliate malignant biliary obstruction and has a high frequency of stent migration, difficulty in retrieval and stricture recurrence after stent removal. This study aimed to design a novel retrievable SEMS dedicated to the treatment of extrahepatic BBS and evaluate its clinical efficacy and safety. A short fully covered SEMS (FCSEMS) with a retrieval lasso was designed for the specific treatment of BBS. A total of 45 patients with segmental extrahepatic BBS were included in this study. The stent was placed entirely inside the bile duct with only the retrieval lasso extending from the papilla. The stents were recommended to be in situ for 6 to 12 months before removal. The FCSEMS was successfully placed in all 45 patients. In all, 33 patients had their FCSEMS successfully removed after a mean period of 8.6 ± 3.7 (range 2-15.5) months. Stent migration occurred in 9.1% of the patients. During a mean follow-up of 18.9 months after stent removal, recurrent stricture was found in 2 (6.1%) patients and was successfully treated with a second FCSEMS. Overall, the strictures resolved in 30/33 (90.9%) patients. Intraductal placement of a short FCSEMS is suitable for the treatment of segmental extrahepatic BBS. This new removable design offered prolonged stenting and drainage for BBS for up to one year with minimal complications. © 2013 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

  11. Treatment of esophagopleural fistulas using covered retrievable expandable metallic stents.

    PubMed

    Kim, Tae-Hyung; Shin, Ji Hoon; Kim, Kyung Rae; Park, Jung-Hoon; Kim, Jin Hyoung; Song, Ho-Young

    2014-04-01

    To evaluate the clinical efficacy of placement of covered retrievable expandable metallic stents for esophagopleural fistulas (EPFs). During the period 1997-2013, nine patients with EPF were treated using covered retrievable expandable metallic stents. The underlying causes of EPF were esophageal carcinoma (n = 6), lung cancer (n = 2), and postoperative empyema for Boerhaave syndrome (n = 1). Technical success was achieved in eight patients (88.9%). In one patient, incomplete EPF closure was due to incomplete stent expansion. Clinical success, defined as complete EPF closure within 7 days, was achieved in five patients (55.6%). Overall fistula persistence (n = 1) or reopening (n = 4) occurred in five patients (55.6%) 0-15 days after stent placement. The causes of reopening were due to the gap between the stent and the esophagus (n = 3) or stent migration (n = 1). For fistula persistence or reopening, additional interventional management, such as gastrostomy, stent removal, or stent reinsertion, was performed. Stent migration occurred as a complication in one patient with EPF from a benign cause secondary to postoperative empyema. In the eight patients who died during the follow-up period, the mean and median survival times were 78.8 days and 46 days, respectively. Placement of a covered expandable metallic esophageal stent for the palliative treatment of EPF is technically feasible, although the rate of clinical success was poor secondary to fistula persistence or reopening. Fistula reopening was caused by the gap between the stent and the esophagus or by stent migration, and additional interventional treatment was useful to ensure enteral nutritional support. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  12. Self-expanding Y stents in the treatment of central airway stenosis: a retrospective analysis.

    PubMed

    Gompelmann, Daniela; Eberhardt, Ralf; Schuhmann, Maren; Heussel, Claus P; Herth, Felix J F

    2013-10-01

    Central airway obstruction (CAO) is a life-threatening situation. Stent insertion re-establishes patency of the central airways. Self-expanding metallic Y stents have been available since 2005, widening the spectrum of interventional bronchoscopic techniques. Retrospective analysis of all patients treated for CAO with a self-expanding metallic Y stent at the Thoraxklinik Heidelberg between May 2005 and January 2009. A total of 43 patients aged 26-81 had a metallic Y stent inserted endoscopically for the treatment of CAO; 39 of these patients (90.7%) had CAO due to malignant disease, four patients (9.3%) due to benign disease. In all 43 patients, the Y stent was deployed without any complications. A longitudinal follow up was possible in 32 of the 43 patients. The stents remained in situ for an average of 107.1 days (range 1-640 days). In 29 patients with malignant CAO the stenosis was successfully overcome with a Y stent; 11 of these patients died within 6 weeks following stent insertion. On follow up the remaining 18 patients showed immediate improvement of dyspnoea. Eight out of the 18 patients (44.4%) tolerated the stent without problems, two (11.1%) required further stenting, six (33.3%) had complications such as increased secretions, cough, dyspnoea or granulation tissue formation. The stent was removed in one patient (5.6%) due to increased secretions, and in another (5.6%) as the stent was no longer required due to successful tumour-specific therapy. Placement of Y stents in symptomatic CAO allows for quick relief of symptoms. Severe complications are rare. Stent removal is possible after successful treatment of the primary tumour. However, the prognostic indicator for survival is the underlying malignancy.

  13. The integrated place of tracheobronchial stents in the multidisciplinary management of large post-pneumonectomy fistulas: our experience using a novel customised conical self-expandable metallic stent.

    PubMed

    Dutau, Hervé; Breen, David Patrick; Gomez, Carine; Thomas, Pascal Alexandre; Vergnon, Jean-Michel

    2011-02-01

    Stump dehiscence after pneumonectomy is a cause of morbidity and mortality in patients treated for non-small-cell lung carcinoma. Surgical repair remains the treatment of choice but can be postponed or contraindicated. Bronchoscopic techniques may be an option with curative intent or as a bridge towards definitive surgery. The aim of the study is to evaluate the efficacy and the outcome of a new customised covered conical self-expandable metallic stent in the management of large bronchopleural fistulas complicating pneumonectomies. A case series using chart review of non-operable patients presenting with large bronchopleural fistulas (>6mm) post-pneumonectomies as a definitive treatment with curative intent for non-small-cell lung carcinomas and requiring the use of a dedicated conical shaped stent in two tertiary referral centres. Seven patients presenting large post-pneumonectomy fistulas (between 6 and 12 mm) were included. Cessation of the air leak and clinical improvement was achieved in all the patients after stent placement. Stent-related complications (two migrations and one stent rupture) were successfully managed using bronchoscopic techniques in two patients and surgery in one. Mortality, mainly related to overwhelming sepsis, was 57%. Delayed definitive surgery was achieved successfully in three patients (43%). This case series assesses the short-term clinical efficacy of a new customised covered conical self-expandable metallic stent in the multidisciplinary management of large bronchopleural fistulas complicating pneumonectomies in patients deemed non-operable. Long-term benefits are jeopardised by infectious complications. Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

  14. Effects of the temporary placement of a self-expandable metallic stent in benign pyloric stenosis.

    PubMed

    Choi, Won Jae; Park, Jong-Jae; Park, Jain; Lim, Eun-Hye; Joo, Moon Kyung; Yun, Jae-Won; Noh, Hyejin; Kim, Sung Ho; Choi, Woo Seok; Lee, Beom Jae; Kim, Ji Hoon; Yeon, Jong Eun; Kim, Jae Seon; Byun, Kwan Soo; Bak, Young-Tae

    2013-07-01

    The use of self-expandable metallic stents (SEMS) is an established palliative treatment for malignant stenosis in the gastrointestinal tract; therefore, its application to benign stenosis is expected to be beneficial because of the more gradual and sustained dilatation in the stenotic portion. We aimed in this prospective observational study to evaluate the efficacy and safety of temporary SEMS placement in benign pyloric stenosis. Twenty-two patients with benign stenosis of the prepylorus, pylorus, and duodenal bulb were enrolled and underwent SEMS placement. We assessed symptom improvement, defined as an increase of at least 1 degree in the gastric-outlet-obstruction scoring system after stent insertion. No major complications were observed during the procedures. After stent placement, early symptom improvement was achieved in 18 of 22 patients (81.8%). During the follow-up period (mean 10.2 months), the stents remained in place successfully for 6 to 8 weeks in seven patients (31.8%). Among the 15 patients (62.5%) with stent migration, seven (46.6%) showed continued symptomatic improvement without recurrence of obstructive symptoms. Despite the symptomatic improvement, temporary SEMS placement is premature as an effective therapeutic tool for benign pyloric stenosis unless a novel stent is developed to prevent migration.

  15. Effects of the Temporary Placement of a Self-Expandable Metallic Stent in Benign Pyloric Stenosis

    PubMed Central

    Choi, Won Jae; Park, Jain; Lim, Eun-Hye; Joo, Moon Kyung; Yun, Jae-Won; Noh, Hyejin; Kim, Sung Ho; Choi, Woo Seok; Lee, Beom Jae; Kim, Ji Hoon; Yeon, Jong Eun; Kim, Jae Seon; Byun, Kwan Soo; Bak, Young-Tae

    2013-01-01

    Background/Aims The use of self-expandable metallic stents (SEMS) is an established palliative treatment for malignant stenosis in the gastrointestinal tract; therefore, its application to benign stenosis is expected to be beneficial because of the more gradual and sustained dilatation in the stenotic portion. We aimed in this prospective observational study to evaluate the efficacy and safety of temporary SEMS placement in benign pyloric stenosis. Methods Twenty-two patients with benign stenosis of the prepylorus, pylorus, and duodenal bulb were enrolled and underwent SEMS placement. We assessed symptom improvement, defined as an increase of at least 1 degree in the gastric-outlet-obstruction scoring system after stent insertion. Results No major complications were observed during the procedures. After stent placement, early symptom improvement was achieved in 18 of 22 patients (81.8%). During the follow-up period (mean 10.2 months), the stents remained in place successfully for 6 to 8 weeks in seven patients (31.8%). Among the 15 patients (62.5%) with stent migration, seven (46.6%) showed continued symptomatic improvement without recurrence of obstructive symptoms. Conclusions Despite the symptomatic improvement, temporary SEMS placement is premature as an effective therapeutic tool for benign pyloric stenosis unless a novel stent is developed to prevent migration. PMID:23898381

  16. Bronchoscopic management of critical central airway obstruction by thyroid cancer: Combination airway stenting using tracheal and inverted-Y carinal self-expanding metallic stents

    PubMed Central

    Madan, Karan; Shrestha, Prajowl; Garg, Rakesh; Hadda, Vijay; Mohan, Anant; Guleria, Randeep

    2017-01-01

    Central airway obstruction (CAO) can result from various benign and malignant etiologies. Anaplastic thyroid cancer (ATC) is the most aggressive form of thyroid cancer. Rapid airway compromise is the main cause of death in ATC. We report a patient with ATC who presented with a large neck mass leading to CAO with long segment tracheal and right main bronchial compression and respiratory failure. Urgent Rigid Bronchoscopy was performed for airway stabilization and patient was managed with a combination airway stenting approach. A combination of self expanding, metallic, covered inverted Y and straight tracheal stents was used to stabilize the near complete airway structure. We herein highlight the role of therapeutic rigid bronchoscopy with airway stenting as an efficacious treatment modality for management of malignant CAO. PMID:28360477

  17. [Numerical modeling of shape memory alloy vascular stent's self-expandable progress and "optimized grid" of stent].

    PubMed

    Xu, Qiang; Liu, Yulan; Wang, Biao; He, Jin

    2008-10-01

    Vascular stent is an important medical appliance for angiocardiopathy. Its key deformation process is the expandable progress of stent in the vessel. The important deformation behaviour corresponds to two mechanics targets: deformation and stress. This paper is devoted to the research and development of vascular stent with proprietary intellectual property rights. The design of NiTinol self-expandable stent is optimized by means of finite element software. ANSYS is used to build the finite element simulation model of vascular stent; the molding material is NiTinol shape memory alloy. To cope with the factors that affect the structure of stent, the shape of grid and so on, the self-expanding process of Nitinol stent is simulated through computer. By making a comparison between two kinds of stents with similar grid structure, we present a new concept of "Optimized Grid" of stent.

  18. Tracheal obstruction caused by an expandable metallic stent: a case of successful removal of the stent.

    PubMed

    Okuyama, Hiroomi; Kubota, Akio; Kawahara, Hisayoshi; Oue, Takaharu; Nose, Satoko; Ihara, Toshiyuki

    2005-07-01

    We report a case of tracheal obstruction caused by an expandable metallic stent. A 3-month-old girl with severe tracheomalacia had a placement of a Palmaz stent. At 3 years of age, she developed progressive dyspnea. The CT scan showed tracheal obstruction caused by granulation tissue over the stent. At operation, the stent was found to have penetrated the posterior tracheal wall. Under partial cardiopulmonary bypass, the stent was removed along with the membranous wall of the trachea, and the trachea was reconstructed using slide tracheoplasty. Tracheal obstruction is one of the serious complications caused by an expandable metallic stent. Direct open approach to the trachea under cardiopulmonary bypass is thought to be a safe way to manage this problem.

  19. Fully covered self-expanding metal stents are effective for benign esophagogastric disruptions and strictures.

    PubMed

    Wilson, Jennifer L; Louie, Brian E; Farivar, Alexander S; Vallières, Eric; Aye, Ralph W

    2013-12-01

    Self-expanding fully covered metal stents (CSs) are ideal for use in benign esophagogastric disease. We reviewed our experience with CS to evaluate outcomes, to determine a role for CS in a standard treatment for benign esophageal conditions, and to compare our results with recently published studies. We performed a retrospective chart review from 2005 to 2012. A total of 57 CSs were placed in 44 patients. Indications were stricture (11 patients), anastomotic leak (20), perforation (7), and tracheoesophageal fistulae (6). For GI tract disruptions, open repair or diversion was avoided in 31/33 patients (93.9 %) but required an associated drainage procedure in 22/33 (67 %) patients. Resolution does not depend on achieving radiological control with 6/26 (23 %) having evidence of a persistent leak. Benign strictures were dilated at a mean of 3.7 times prior to stenting. Adjunctive intra-mucosal steroid injections were used in 8/11 patients. Stents were removed at a mean of 33 days. At a mean of 283 days of follow-up, 6/11 (54.5 %) had symptom resolution. The most common complication was stent migration occurring in 17.5 % of patients overall. Covered stents are an effective adjunct in the management of benign upper gastrointestinal tract fistulae, leaks, perforations and benign strictures.

  20. Partially covered self-expandable metal stents versus polyethylene stents for malignant biliary obstruction: A cost-effectiveness analysis

    PubMed Central

    Barkun, Alan N; Adam, Viviane; Martel, Myriam; AlNaamani, Khalid; Moses, Peter L

    2015-01-01

    BACKGROUND/OBJECTIVE: Partially covered self-expandable metal stents (SEMS) and polyethylene stents (PES) are both commonly used in the palliation of malignant biliary obstruction. Although SEMS are significantly more expensive, they are more efficacious than PES. Accordingly, a cost-effectiveness analysis was performed. METHODS: A cost-effectiveness analysis compared the approach of initial placement of PES versus SEMS for the study population. Patients with malignant biliary obstruction underwent an endoscopic retrograde cholangiopancreatography to insert the initial stent. If the insertion failed, a percutaneous transhepatic cholangiogram was performed. If stent occlusion occurred, a PES was inserted at repeat endoscopic retrograde cholangiopancreatography, either in an outpatient setting or after admission to hospital if cholangitis was present. A third-party payer perspective was adopted. Effectiveness was expressed as the likelihood of no occlusion over the one-year adopted time horizon. Probabilities were based on a contemporary randomized clinical trial, and costs were issued from national references. Deterministic and probabilistic sensitivity analyses were performed. RESULTS: A PES-first strategy was both more expensive and less efficacious than an SEMS-first approach. The mean per-patient costs were US$6,701 for initial SEMS and US$20,671 for initial PES, which were associated with effectiveness probabilities of 65.6% and 13.9%, respectively. Sensitivity analyses confirmed the robustness of these results. CONCLUSION: At the time of initial endoscopic drainage for patients with malignant biliary obstruction undergoing palliative stenting, an initial SEMS insertion approach was both more effective and less costly than a PES-first strategy. PMID:26125107

  1. Safety and Efficacy of a Fully Covered Self-Expandable Metallic Stent in Benign Airway Stenosis.

    PubMed

    Fortin, Marc; Lacasse, Yves; Elharrar, Xavier; Tazi-Mezalek, Rachid; Laroumagne, Sophie; Guinde, Julien; Astoul, Philippe; Dutau, Hervé

    2017-01-01

    The use of self-expandable metallic stents (SEMS) in benign airway disease was the object of a boxed warning from the United States Food and Drug Administration in 2005 due to the risk of stent-related complications and difficulties associated with their removal. Third-generation fully covered SEMS have been commercialized since this warning and theoretically should not present the same difficulties associated with removal as they cannot become embedded in the airway mucosa. We aimed to examine the safety and efficacy of a specific third-generation SEMS, the Silmet stent. We reviewed the records of all patients treated for benign airway stenosis with third-generation Silmet SEMS from January 2011 to December 2015 at the North Hospital of Marseilles, France. Forty SEMS were inserted in 30 patients over this period. Twenty (50.0%) stents were removed because of stent-related complications after a median of 77.0 ± 96.6 days (migration 32.5%, granulation tissue formation 7.5%, subjective intolerance 5.0%, mucus plugging 2.5%, laryngeal edema 2.5%). There were no cases of stent-related mortality. All complications were managed successfully endoscopically. Thirty-six stents (90.0%) were removed successfully after a median of 122.0 ± 113.2 days without any complications. The clinical success rate of stent treatment was 40.7%. Third-generation SEMS are a safe treatment option for complex benign airway stenosis, but complications requiring stent removal are frequent. Further studies are needed to compare the performance of third-generation SEMS and silicone stents in benign airway stenosis. © 2017 S. Karger AG, Basel.

  2. Safety and benefits of self-expandable metallic stents with chemotherapy for malignant gastric outlet obstruction.

    PubMed

    Miyabe, Katsuyuki; Hayashi, Kazuki; Nakazawa, Takahiro; Sano, Hitoshi; Yamada, Tomonori; Takada, Hiroki; Naitoh, Itaru; Shimizu, Shuya; Kondo, Hiromu; Nishi, Yuji; Yoshida, Michihiro; Umemura, Shuichiro; Hori, Yasuki; Kato, Akihisa; Ohara, Hirotaka; Joh, Takashi

    2015-07-01

    The influence of chemotherapy on placement of self-expandable metallic stents (SEMS) for malignant gastric outlet obstruction (MGOO) has not been evaluated extensively. We investigated the influence of chemotherapy on the clinical outcomes of SEMS placement for MGOO. A total of 152 cancer patients with MGOO from a university hospital and affiliate hospitals were included. The patients were classified according to chemotherapy status and evaluated for palliative efficacy and safety of SEMS placement. Technical success rate, time to oral intake, and parameters indicating improvement of physical condition did not differ between the with- and without-chemotherapy groups after stent placement. Re-intervention and stent migration were significantly more frequent in the with-chemotherapy group than in the without-chemotherapy group after stent placement (re-intervention, 32.4% vs 7.8%, P = 0.0005; stent migration, 13.5% vs 1.7%, P = 0.0097). The frequency of adverse events did not differ between the with- and without-chemotherapy groups. Although chemotherapy after stent placement was an independent predictive factor for shortening the stent patency period (hazard ratio [HR], 3.10; P = 0.0264), the use of additional stents facilitated uneventful recovery and further prolonged survival time (HR, 0.60; P = 0.0132). Various cancer patients with MGOO can undergo SEMS placement safely regardless of chemotherapy, and concurrent chemotherapy after stent placement can prolong survival time, although re-intervention and stent migration may be increased. © 2015 The Authors. Digestive Endoscopy © 2015 Japan Gastroenterological Endoscopy Society.

  3. [Self-expandable metallic biliary endoprosthesis in malignant obstructive jaundice].

    PubMed

    Güitrón-Cantú, Alfredo; Adalid-Martínez, Raúl; Gutiérrez-Bermúdez, José A

    2005-01-01

    Implantation of metallic stents for malignant biliary strictures has been recognized to be effective alternatives. To show our experience in metallic stents for palliation of malignant biliary strictures. Seventy three patients (38 males, 35 females, mean age 64.26) with malignant biliary strictures have been treated by implantation of metallic stents. Causes of obstruction were pancreatic carcinoma (23/73, 31.5%), bile duct carcinoma (31/73, 42.5%), carcinoma of ampula of Vater (11/73, 15%) and Klatskin tumor (3/73, 4.1%). Endoscopic procedure was successful in all cases. Neither procedure-related morbidity nor mortality was observed. Life surviving curve was 9 months and showed significant difference (p < 0.0071) in patients with carcinoma of ampula of Vater. Self-expanding metal endoprosthesis is a recognized method of palliation in malignant biliary obstruction. It efficiently relieves jaundice and generally improves comfort and nutritional status during the patient's remaining lifetime. The metallic stents are advantageous in patients surviving 6 months or less.

  4. Removable self-expanding metal stents insertion for the treatment of perforations and postoperative leaks of the esophagus.

    PubMed

    Nasa, Mukesh; Sharma, Zubin Dev; Choudhary, Narendra S; Puri, Rajesh; Sud, Randhir

    2016-03-01

    Esophageal rupture, spontaneous or iatrogenic, is associated with significant morbidity and mortality. The current study aims at highlighting the various clinical scenarios, where esophageal fully covered self-expanding removable metal stents (FCSEMS) can be used in esophageal rupture. In patients who underwent insertion of FCSEMS between January 2013 and June 2014, all data regarding demographics, indications, insertion, removal, and outcomes were studied retrospectively. Seven patients underwent the placement of esophageal covered SEMS. Two patients had Boerhaave syndrome, two had leak following the repair of aortic aneurysm, one had extensive esophageal injury following transesophageal echocardiography, one had carcinoma esophagus with tracheaesophageal fistula, and one had dehiscence of esophagogastric anastomosis. Stent insertion was successful in all the patients; one had stent migration which was managed endoscopically. Two patients died due to underlying illness; the rest had successful removal of stents after 8-10 weeks and good outcomes. Esophageal FCSEMS placement is safe and effective modality in management of patients with esophageal rupture.

  5. Novel characteristics of traction force in biliary self-expandable metallic stents.

    PubMed

    Hori, Yasuki; Hayashi, Kazuki; Yoshida, Michihiro; Naitoh, Itaru; Ban, Tesshin; Miyabe, Katsuyuki; Kondo, Hiromu; Nishi, Yuji; Umemura, Shuichiro; Fujita, Yasuaki; Natsume, Makoto; Kato, Akihisa; Ohara, Hirotaka; Joh, Takashi

    2017-05-01

    In recent years, knowledge concerning the mechanical properties of self-expandable metallic stents (SEMS) has increased. In a previous study, we defined traction force and traction momentum and reported that these characteristics are important for optimal stent deployment. However, traction force and traction momentum were represented as relative values and were not evaluated in various conditions. The purpose of the present study was to measure traction force in various situations assumed during SEMS placement. Traction force and traction momentum were measured in non-stricture, stricture, and angled stricture models using in-house equipment. Stricture and angled stricture models had significantly higher traction force and traction momentum than those of the non-stricture model (stricture vs non-stricture: traction force, 7.2 N vs 1.4 N, P < 0.001; traction momentum, 237.8 Ns vs 62.3 Ns, P = 0.001; angled stricture vs non-stricture: traction force, 7.4 N vs 1.4 N, P < 0.001; traction momentum, 307.2 Ns vs 62.3 Ns, P < 0.001). Traction force was variable during SEMS placement and was categorized into five different stages, which were similar in both the stricture and angled stricture models. We measured traction force and traction momentum under simulated clinical conditions and demonstrated that strictures and the angular positioning of the stent influenced the traction force. Clinicians should be aware of the transition of the traction force and should schedule X-ray imaging during SEMS placement. © 2017 Japan Gastroenterological Endoscopy Society.

  6. SU-E-T-115: Dose Perturbation Study of Self-Expandable Metal and Polyester Esophageal Stents in Proton Therapy Beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, S; Li, Z; Jalaj, S

    2014-06-01

    Purpose: This work investigates dose perturbations due to Self-expandable metal and polyester esophageal stents undergoing proton radiotherapy for esophageal cancer. Methods: Five commercially available esophageal stents made of nitinol (Evolution, Wallflex and Ultraflex), stainless steel (Z-Stent) and polyester (Polyflex) were tested. Radiochromic film (GafChromic EBT3 film, Ashland, Covington, KY) wrapped around a stent and a 12cc syringe was irradiated with 2CGE (Cobalt Gray Equivalent) of proton beam in a custom fabricated acrylic phantom. An air-hollow syringe simulates the esophagus. Results: The Z-stent created the largest dose perturbations ranges from -14.5% to 6.1% due to the steel composition. The WallFlex, Evolutionmore » and Ultraflex stents produced the dose perturbation ranges of (−9.2%∼8.6%), (−6.8%∼5.7%) and (−6.2%∼6.2%), respectively. The PolyFlex stent contains the radiopaque tungsten markers located top, middle and bottom portions. When the focal cold spots induced by the markers were excluded in the analysis, the dose perturbation range was changed from (−11.6%∼6.4%) to (−0.6%∼5.0%). Conclusion: The magnitude of dose perturbation is related to material of a metallic stent. The non-metallic stent such as PolyFlex shows relatively lower dose perturbation than metallic stents except a radiopaque marker region. Overall Evolution and Ultraflex stent appear to be less dose perturbations. The largest dose perturbations (cold spots) were located at both edges of stents in distal area for the single proton beam irradiation study. The analysis of more than two proton beam which is more typical clinical beam arrangement would be necessary to minimize the doe perturbation effect in proton ratiotherapy.« less

  7. Temporary placement of fully covered self-expandable metal stents in benign biliary strictures.

    PubMed

    Ryu, Choong Heon; Kim, Myung Hwan; Lee, Sang Soo; Park, Do Hyun; Seo, Dong Wan; Lee, Sung Koo

    2013-07-01

    Benign biliary strictures (BBSs) have been endoscopically managed with plastic stent placement. However, data regarding fully covered self-expandable metal stents (FCSEMSs) in BBS patients remain scarce in Korea. Forty-one patients (21 men, 65.9%) with BBSs underwent FCSEMS placement between February 2007 and July 2010 in Asan Medical Center. Efficacy and safety were evaluated retrospectively. Patients were considered to have resolution if they showed evidence of stricture resolution on cholangiography and if an inflated retrieval balloon easily passed through the strictures at FCSEMS removal. The mean FCSEMS placement time was 3.2 (1.9-6.2) months. Patients were followed for a mean of 10.2 (1.0-32.0) months after FCSEMS removal. The BBS resolution rate was confirmed in 38 of 41 (92.7%) patients who underwent FCSEMS removal. After FCSEMS removal, 6 of 38 (15.8%) patients experienced symptomatic recurrent stricture and repeat stenting was performed. When a breakdown by etiology of stricture was performed, 14 of 15 (93.3%) patients with chronic pancreatitis, 17 of 19 (89.5%) with gall stone-related disease, 4 of 4 (100%) with surgical procedures, and 2 of 2 (100%) with BBSs of other etiology had resolution at FCSEMS removal. Complications related to stent therapy occurred in 12 (29%) patients, including post-ERCP pancreatitis (n=4), proximal migration (n=3), distal migration (n=3), and occlusion (n=2). Temporary FCSEMS placement in BBS patients offers a potential alternative to plastic stenting. However, because of the significant complications and modest resolution rates, the potential benefits and risks should be evaluated in further investigations.

  8. Efficacy and safety of a new fully covered self-expandable non-foreshortening metal esophageal stent.

    PubMed

    Dua, Kulwinder S; Latif, Sahibzada U; Yang, Juliana F; Fang, Tom C; Khan, Abdul; Oh, Young

    2014-10-01

    Fully covered esophageal self-expandable metal stents (SEMSs) are potentially removable but can be associated with high migration rates. For precise positioning, non-foreshortening SEMSs are preferred. Recently, a new fully covered non-foreshortening SEMS with anti-migration features was introduced. To evaluate the efficacy and safety of this new esophageal SEMS. Retrospective study. Single, tertiary-care center. Consecutive patients with malignant and benign strictures with dysphagia grade of ≥3 and patients with fistulas/leaks were studied. Stent placement and removal. Technical success in stent deployment/removal, efficacy in relieving dysphagia and sealing fistulas/leaks, and adverse events. Forty-three stents were placed in 35 patients (mean [± standard deviation] age 65 ± 11 years; 31 male), 24 for malignant and 11 for benign (5 strictures, 6 leaks) indications. Technical success in precise SEMS placement was 100%. The after-stent dysphagia grade improved significantly (at 1 week: 1.5 ± 0.7; at 4 weeks: 1.2 ± 0.4; baseline: 3.8 ± 0.4; P < .0001). Twenty stents were removed for clinical indications, with technical success of 100%. All leaks sealed after SEMS placement and did not recur after stent removal. All benign strictures recurred after stent removal. Adverse events included migration (14%), chest pain (11%), and dysphagia from tissue hyperplasia (6%). There was no stent-related mortality. Nonrandomized, single-center study. The new esophageal SEMS was effective in relieving malignant dysphagia, allowed for precise placement, and was easily removable. It was effective in treating benign esophageal fistulas and leaks. Stent-related adverse events were acceptable. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  9. Treatment of Postoperative Leaks of the Upper Gastrointestinal Tract with Colonic Self-Expandable Metal Stents.

    PubMed

    Sousa, Paula; Castanheira, António; Martins, Diana; Pinho, Juliana; Araújo, Ricardo; Cancela, Eugénia; Ministro, Paula; Silva, Américo

    2017-07-01

    The use of self-expandable metal stents (SEMS) for the treatment of postoperative leaks of the upper gastrointestinal tract is already established. However, there are discrepancies between the relatively small caliber of the esophageal stents available and the postsurgical luminal size, which may determine an inadequate juxtaposition. As colonic stents have a bigger diameter, they might be more adequate. Additionally, stents with a larger diameter might have a lower risk of migration. The aim of this study was to evaluate the efficacy and complications associated with the use of colonic fully covered SEMS (FSEMS) in the treatment of postoperative leaks in critical patients. All patients with postoperative leaks of the upper gastrointestinal tract treated with colonic stents (Hanarostent® CCI) between 2010 and 2013 were retrospectively included. Four patients with postoperative leaks were treated with colonic SEMS. The underlying surgeries were a gastric bypass, an esophagogastrectomy for Boerhaave syndrome, a primary repair of esophagopleural fistula due to Boerhaave syndrome, and an esophagectomy due to esophageal cancer. The leaks were detected on average 17 days after the initial surgery. All patients needed admission to a critical care unit after index surgery. Stent placement was technically feasible in all patients. The median residence time of the stents was 7 weeks, and no complications were verified when they were removed. There were no cases of stent migration. The treatment was successful in all patients, with complete healing of the leaks. The placement of colonic FSEMS seems to be successful and safe in the treatment of postoperative leaks of the upper gastrointestinal tract.

  10. Predictors of outcomes in patients undergoing covered and uncovered self-expandable metal stent placement for malignant gastric outlet obstruction: a multicenter study.

    PubMed

    Hori, Yasuki; Naitoh, Itaru; Hayashi, Kazuki; Ban, Tesshin; Natsume, Makoto; Okumura, Fumihiro; Nakazawa, Takahiro; Takada, Hiroki; Hirano, Atsuyuki; Jinno, Naruomi; Togawa, Shozo; Ando, Tomoaki; Kataoka, Hiromi; Joh, Takashi

    2017-02-01

    Uncovered self-expandable metal stents (U-SEMSs) and covered self-expandable metal stents (C-SEMSs) are available for palliative therapy for malignant gastric outlet obstruction (GOO). However, clinical differences and indications between the 2 types of SEMSs have not been elucidated. We retrospectively compared 126 patients with U-SEMS and 126 patients with C-SEMSs with regard to clinical outcome and factors predictive of clinical improvement after SEMSs placement. No significant difference was observed between the U-SEMS and C-SEMS groups with respect to technical success, clinical success, GOO score, or time to stent dysfunction. Stent migration was significantly more frequent in patients with C-SEMSs (U-SEMSs, .79%; C-SEMSs, 8.73%; P = .005). Karnofsky performance status, chemotherapy, peritoneal dissemination, and stent expansion ≤ 30% were associated significantly with poor GOO score improvement in multivariable analyses, but stent type was not (P = .213). In subgroup analyses, insufficient (≤30%) stent expansion was an independent factor in patients with U-SEMSs (P = .041) but not C-SEMSs. In the insufficient stent expansion subgroup, C-SEMSs was associated significantly with superior clinical improvement compared with U-SEMSs (P = .01). Insufficient stent expansion was observed more frequently in patients with GI obstruction because of anastomotic sites or metastatic cancer (44.8% [13/29], P = .001). No clinical difference, apart from stent migration, was observed between patients with U-SEMSs and C-SEMSs. GI obstruction because of an anastomotic site or metastatic cancer may be an indication for C-SEMS use to improve oral intake after SEMSs placement. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  11. Wing-shaped plastic stents vs. self-expandable metal stents for palliative drainage of malignant distal biliary obstruction: a randomized multicenter study.

    PubMed

    Schmidt, Arthur; Riecken, Bettina; Rische, Susanne; Klinger, Christoph; Jakobs, Ralf; Bechtler, Matthias; Kähler, Georg; Dormann, Arno; Caca, Karel

    2015-05-01

    Previous studies have shown superior patency rates for self-expandable metal stents (SEMS) compared with plastic stents in patients with malignant biliary obstruction. The aim of this study was to compare stent patency, patient survival, and complication rates between a newly designed, wing-shaped, plastic stent and SEMSs in patients with unresectable, malignant, distal, biliary obstruction. A randomized, multicenter trial was conducted at four tertiary care centers in Germany. A total of 37 patients underwent randomization between March 2010 and January 2013. Patients underwent endoscopic retrograde cholangiography with insertion of either a wing-shaped, plastic stent without lumen or an SEMS.  Stent failure occurred in 10/16 patients (62.5 %) in the winged-stent group vs. 4/18 patients (22.2 %) in the SEMS group (P = 0.034). The median time to stent failure was 51 days (range 2 - 92 days) for the winged stent and 80 days (range 28 - 266 days) for the SEMS (P = 0.002). Early stent failure (< 8 weeks after placement) occurred in 8 patients (50 %) vs. 2 patients (11.1 %), respectively (P = 0.022). After obtaining the results from this interim analysis, the study was discontinued because of safety concerns. The frequency of stent failure was significantly higher in the winged-stent group compared with the SEMS group. A high incidence of early stent failure within 8 weeks was observed in the winged-stent group. Thus, the winged, plastic stent without central lumen may not be appropriate for mid or long term drainage of malignant biliary obstruction. Study registration ClinicalTrials.gov (NCT01063634). © Georg Thieme Verlag KG Stuttgart · New York.

  12. The use of balloon-expandable metallic stents in the treatment of pediatric tracheomalacia and bronchomalacia.

    PubMed

    Furman, R H; Backer, C L; Dunham, M E; Donaldson, J; Mavroudis, C; Holinger, L D

    1999-02-01

    To evaluate the use of balloon-expandable metallic stents in the treatment of children with tracheomalacia and bronchomalacia in whom conventional therapy has failed. Retrospective case series. Tertiary pediatric otolaryngology and cardiothoracic surgery referral center. Six patients were identified as having undergone bronchoscopic placement of metallic balloon-expandable stents between 1994 and 1997. The age at stent placement, prior surgical interventions, and indications for and sites of stent placement were noted. Also, the complications related to stent placement and the current airway status of the patients were reviewed. Twelve balloon-expandable metallic angioplasty stents (Palmaz; Johnson & Johnson Interventional Systems Co, Warren, NJ) were placed bronchoscopically in 6 patients. Six stents were placed in the lower trachea, and 6 were placed in the main bronchi. The stents were balloon expanded under fluoroscopic guidance. Discontinuation of mechanical ventilation. The age at stent placement ranged from 1.5 to 38 months (mean age at placement, 10 months). The indications for stent placement were (1) tracheomalacia or bronchomalacia, (2) pericardial patch or slide tracheoplasty failure, and (3) bronchomalacia caused by tetralogy of Fallot and large pulmonary arteries. The primary complication of stent placement was postoperative granulation tissue formation. One patient required the removal of 2 tracheal stents because of granulation tissue formation. There were 2 deaths in the series, 1 possibly related to stent placement. Four of the 6 patients were weaned from mechanical ventilation, and 3 experienced prolonged relief of airway obstruction. Metallic balloon-expandable stents are effective in relieving lower tracheomalacia and bronchomalacia in select patients. Only patients in whom conventional therapy has failed should be considered for stent placement.

  13. An approach to tracheostomy in a patient with an expandable metallic tracheal stent.

    PubMed

    Madden, Brendan P; Sheth, Abhijat

    2005-09-01

    With increasing use of expandable metallic stents to manage patients with a variety of endobronchial pathologies, some will have a subsequent need for tracheostomy insertion. We describe a successful technique to insert a tracheostomy using rigid and fibre-optic bronchoscopy in a patient who had an 8 cm expandable metallic tracheal stent deployed previously on account of tracheomalacia.

  14. Long-term outcomes of covered self-expandable metal stents for treating benign biliary strictures.

    PubMed

    Park, Jin-Seok; Lee, Sang Soo; Song, Tae Jun; Park, Do Hyun; Seo, Dong-Wan; Lee, Sung Koo; Han, Seungbong; Kim, Myung-Hwan

    2016-05-01

    Fully covered, self-expandable metal stents (FCSEMSs) are acceptable tools for treating benign biliary stricture (BBS). However, little is known about the long-term outcomes of this technique. The aim of the present study was to evaluate the procedural and long-term outcomes of FCSEMSs for treating BBSs. A total of 134 consecutive patients (median age 56 years; range 21 - 83) with BBS were retrospectively reviewed. The main outcomes were technical and clinical success, stricture resolution, recurrence, and adverse events. Outcomes were analyzed by reviewing patient medical records. The success rates of FCSEMS placement and removal were 99.3 % and 98.2 %, respectively. Stricture resolution occurred in 103/132 (78.0 %) of the patients (median stent duration, 93 days; range 1 - 489). The associated factors for stricture resolution were longer stent indwelling period (≥ 120 days) and absence of stent migration. Stricture recurrence was seen in 26/103 patients (25.2 %; 95 % confidence interval [CI] 0.17 - 0.34) within a median of 390 days (range 4 - 903 days). Chronic pancreatitis was associated with stricture recurrence (hazard ratio [HR] 2.59, 95 %CI 1.20 - 5.61; P = 0.02). Stent migration occurred in 41/132 patients (31.1 %; 95 %CI 0.23 - 0.39). The FCSEMS with anchoring flaps appeared to protect against stent migration (HR 0.22, 95 %CI 0.08 - 0.63; P < 0.01). FCSEMSs had a high success rate for BBS resolution. Longer indwelling periods and the absence of stent migration might be important factors for stricture resolution. © Georg Thieme Verlag KG Stuttgart · New York.

  15. The use of expandable metallic airway stents for tracheobronchial obstruction in children.

    PubMed

    Filler, R M; Forte, V; Fraga, J C; Matute, J

    1995-07-01

    Expandable metallic angioplasty stents (Palmaz stent) have been implanted in the trachea and/or bronchi of seven children. Three children had severe tracheal stenosis after tracheoplasty for congenital tracheal stenosis repair, and four had tracheomalacia or bronchomalacia with or without vascular compression. The mean age at stenting was 9.7 months (range, 2 to 15 months). Balloon expandable stents were inserted into the trachea or bronchus through a 3.5-mm bronchoscope under fluoroscopic control. Initially a single tracheal stent was used for all patients except for one with obstruction in the trachea and both bronchi, in whom three stents were implanted. Three children had recurrent airway obstruction 1 month later; one was cured with a second stent; one child died 1 year later; and the other is being treated for heart disease. The others have no serious respiratory problems. The stents in all have been in place for 1 to 25 (mean, 11) months. No immediate complications were noted. Early and late bronchoscopy showed incomplete epithelialization of the stent and patches of granulation tissue on it. Two stents were removed bronchoscopically, one at the completion of treatment for tracheomalacia and the other at the time of recurrent airway obstruction. This preliminary experience indicates that expandable metallic stents have a useful role in the treatment of selected lower airway obstructions.

  16. A Novel Partially Covered Self-Expandable Metallic Stent with Proximal Flare in Patients with Malignant Gastric Outlet Obstruction.

    PubMed

    Takahara, Naminatsu; Isayama, Hiroyuki; Nakai, Yousuke; Yoshida, Shuntaro; Saito, Tomotaka; Mizuno, Suguru; Yagioka, Hiroshi; Kogure, Hirofumi; Togawa, Osamu; Matsubara, Saburo; Ito, Yukiko; Yamamoto, Natsuyo; Tada, Minoru; Koike, Kazuhiko

    2017-07-15

    Endoscopic placement of self-expandable metal stents (SEMSs) has emerged as a palliative treatment for malignant gastric outlet obstruction (GOO). Although covered SEMSs can prevent tumor ingrowth, frequent migration of covered SEMSs may offset their advantages in preventing tumor ingrowth. We conducted this multicenter, single-arm, retrospective study at six tertiary referral centers to evaluate the safety and efficacy of a partially covered SEMS with an uncovered large-bore flare at the proximal end as an antimigration system in 41 patients with symptomatic malignant GOO. The primary outcome was clinical success, and the secondary outcomes were technical success, stent dysfunction, adverse events, and survival after stent placement. The technical and clinical success rates were 100% and 95%, respectively. Stent dysfunctions occurred in 17 patients (41%), including stent migration in nine (23%), tumor ingrowth in one (2%), and tumor overgrowth in four (10%). Two patients (5%) developed adverse events: one pancreatitis and one perforation. No procedure-related death was observed. A novel partially covered SEMS with a large-bore flare proximal end was safe and effective for malignant GOO but failed to prevent stent migration. Further research is warranted to develop a covered SEMS with an optimal antimigration system.

  17. Self-Expandable Metal Stents for Persisting Esophageal Variceal Bleeding after Band Ligation or Injection-Therapy: A Retrospective Study.

    PubMed

    Müller, Martin; Seufferlein, Thomas; Perkhofer, Lukas; Wagner, Martin; Kleger, Alexander

    2015-01-01

    Despite a pronounced reduction of lethality rates due to upper gastrointestinal bleeding, esophageal variceal bleeding remains a challenge for the endoscopist and still accounts for a mortality rate of up to 40% within the first 6 weeks. A relevant proportion of patients with esophageal variceal bleeding remains refractory to standard therapy, thus making a call for additional tools to achieve hemostasis. Self-expandable metal stents (SEMS) incorporate such a tool. We evaluated a total number of 582 patients admitted to our endoscopy unit with the diagnosis "gastrointestinal bleeding" according to our documentation software between 2011 and 2014. 82 patients suffered from esophageal variceal bleeding, out of which 11 cases were refractory to standard therapy leading to SEMS application. Patients with esophageal malignancy, fistula, or stricture and a non-esophageal variceal bleeding source were excluded from the analysis. A retrospective analysis reporting a series of clinically relevant parameters in combination with bleeding control rates and adverse events was performed. The initial bleeding control rate after SEMS application was 100%. Despite this success, we observed a 27% mortality rate within the first 42 days. All of these patients died due to non-directly hemorrhage-associated reasons. The majority of patients exhibited an extensive demand of medical care with prolonged hospital stay. Common complications were hepatic decompensation, pulmonary infection and decline of renal function. Interestingly, we found in 7 out of 11 patients (63.6%) stent dislocation at time of control endoscopy 24 h after hemostasis or at time of stent removal. The presence of hiatal hernia did not affect obviously stent dislocation rates. Refractory patients had significantly longer hospitalization times compared to non-refractory patients. Self-expandable metal stents for esophageal variceal bleeding seem to be safe and efficient after failed standard therapy. Stent migration

  18. [Treatment of tracheobronchomalacia with expandable metallic stents].

    PubMed

    Antón-Pacheco Sánchez, J; García Vázquez, A; Cuadros García, J; Cano Novillo, I; Villafruela Sanz, M; Berchi García, F J

    2002-10-01

    Tracheomalacia is an unfrequent disease that causes tracheal collapse during breathing. It is generally associated to esophageal atresia, but cases of primary tracheomalacia and others secondary to extrinsic compression, have also been described. Spontaneous resolution is generally the rule and only a few cases need surgical treatment. When this therapy fails or is not indicated for any reason, endoluminal tracheobronchial stents may be used. We have treated two patients with four expandable metallic stents: one had severe tracheomalacia associated to esophageal atresia and the other tracheobronchomalacia secondary to cardiomegaly. Results have been good in both cases.

  19. Covered Balloon-Expanding Stents in Airway Stenosis.

    PubMed

    Majid, Adnan; Kheir, Fayez; Chung, Jey; Alape, Daniel; Husta, Bryan; Oh, Scott; Folch, Erik

    2017-04-01

    The balloon-expanding stents are widely available but rarely described for use within the tracheobronchial tree. This report describes our experience with these stents in airway stenosis particularly as a lobar salvage therapy. This was a retrospective review of all records in which the balloon-expanding stents were used at a tertiary medical center. Ages, sex, location of stenosis, etiology of stenosis, stent size, duration of stent placement and associated interventions for airway stenosis were recorded. Patient's self-reported respiratory symptoms, dyspnea scale, and radiographic imaging at baseline and after stent placement were also reported. Twenty-one Atrium iCAST stents were inserted in 18 patients with malignant and benign airway disease. The median age was 69.5 years (interquartile range, 53.5 to 74). Most stents (n=20, 95%) were deployed in the lobar airways. There was a significant improvement in the modified Medical Research Council dyspnea scale from median of 3 to 2 (P<0.05). Self-reported respiratory symptoms improved in 14 patients (78%, P<0.05). Radiographic improvement post Atrium iCAST stent placement was achieved in 15 patients (83%). No deaths were related to airway stenting complications. Adverse events related to stents included migration (n=2, 9.5%), granulation tissue formation (n=2, 9.5%) and mucus plugging (n=1, 4.8%). Lobar stenting with balloon-expanding metallic stents appears feasible, safe and improves symptoms as well as radiographic atelectasis in patients with lobar airway stenosis in this small case series. Larger studies are needed to confirm this observation and to address long-term safety.

  20. Risk factors for technical failure of endoscopic double self-expandable metallic stent placement by partial stent-in-stent method.

    PubMed

    Kawakubo, Kazumichi; Kawakami, Hiroshi; Toyokawa, Yoshihide; Otani, Koichi; Kuwatani, Masaki; Abe, Yoko; Kawahata, Shuhei; Kubo, Kimitoshi; Kubota, Yoshimasa; Sakamoto, Naoya

    2015-01-01

    Endoscopic double self-expandable metallic stent (SEMS) placement by the partial stent-in-stent (PSIS) method has been reported to be useful for the management of unresectable hilar malignant biliary obstruction. However, it is technically challenging, and the optimal SEMS for the procedure remains unknown. The aim of this study was to identify the risk factors for technical failure of endoscopic double SEMS placement for unresectable malignant hilar biliary obstruction (MHBO). Between December 2009 and May 2013, 50 consecutive patients with MHBO underwent endoscopic double SEMS placement by the PSIS method. We retrospectively evaluated the rate of successful double SEMS placement and identified the risk factors for technical failure. The technical success rate for double SEMS placement was 82.0% (95% confidence interval [CI]: 69.2-90.2). On univariate analysis, the rate of technical failure was high in patients with metastatic disease and unilateral placement. Multivariate analysis revealed that metastatic disease was a significant risk factor for technical failure (odds ratio: 9.63, 95% CI: 1.11-105.5). The subgroup analysis after double guidewire insertion showed that the rate of technical success was higher in the laser-cut type SEMS with a large mesh and thick delivery system than in the braided type SEMS with a small mesh and thick delivery system. Metastatic disease was a significant risk factor for technical failure of double SEMS placement for unresectable MHBO. The laser-cut type SEMS with a large mesh and thin delivery system might be preferable for the PSIS procedure. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  1. Clinical outcomes of self-expandable stent placement for benign esophageal diseases: A pooled analysis of the literature

    PubMed Central

    van Halsema, Emo E; van Hooft, Jeanin E

    2015-01-01

    AIM: To analyze the outcomes of self-expandable stent placement for benign esophageal strictures and benign esophageal leaks in the literature. METHODS: The PubMed, Embase and Cochrane databases were searched for relevant articles published between January 2000 and July 2014. Eight prospective studies were identified that analyzed the outcomes of stent placement for refractory benign esophageal strictures. The outcomes of stent placement for benign esophageal leaks, perforations and fistulae were extracted from 20 retrospective studies that were published after the inclusion period of a recent systematic review. Data were pooled and analyzed using descriptive statistics. RESULTS: Fully covered self-expandable metal stents (FC SEMS) (n = 85), biodegradable (BD) stents (n = 77) and self-expandable plastic stents (SEPS) (n = 70) were inserted in 232 patients with refractory benign esophageal strictures. The overall clinical success rate was 24.2% and according to stent type 14.1% for FC SEMS, 32.9% for BD stents and 27.1% for SEPS. Stent migration occurred in 24.6% of cases. The overall complication rate was 31.0%, including major (17.7%) and minor (13.4%) complications. A total of 643 patients were treated with self-expandable stents mainly for postsurgical leaks (64.5%), iatrogenic perforations (19.6%), Boerhaave’s syndrome (7.8%) and fistulae (3.7%). FC SEMS and partially covered SEMS were used in the majority of patients. Successful closure of the defect was achieved in 76.8% of patients and according to etiology in 81.4% for postsurgical leaks, 86.0% for perforations and 64.7% for fistulae. The pooled stent migration rate was 16.5%. Stent-related complications occurred in 13.4% of patients, including major (7.8%) and minor (5.5%) complications. CONCLUSION: The outcomes of stent placement for refractory benign esophageal strictures were poor. However, randomized trials are needed to put this into perspective. The evidence on successful stent placement for benign

  2. Clinical outcomes of self-expandable stent placement for benign esophageal diseases: A pooled analysis of the literature.

    PubMed

    van Halsema, Emo E; van Hooft, Jeanin E

    2015-02-16

    To analyze the outcomes of self-expandable stent placement for benign esophageal strictures and benign esophageal leaks in the literature. The PubMed, Embase and Cochrane databases were searched for relevant articles published between January 2000 and July 2014. Eight prospective studies were identified that analyzed the outcomes of stent placement for refractory benign esophageal strictures. The outcomes of stent placement for benign esophageal leaks, perforations and fistulae were extracted from 20 retrospective studies that were published after the inclusion period of a recent systematic review. Data were pooled and analyzed using descriptive statistics. Fully covered self-expandable metal stents (FC SEMS) (n = 85), biodegradable (BD) stents (n = 77) and self-expandable plastic stents (SEPS) (n = 70) were inserted in 232 patients with refractory benign esophageal strictures. The overall clinical success rate was 24.2% and according to stent type 14.1% for FC SEMS, 32.9% for BD stents and 27.1% for SEPS. Stent migration occurred in 24.6% of cases. The overall complication rate was 31.0%, including major (17.7%) and minor (13.4%) complications. A total of 643 patients were treated with self-expandable stents mainly for postsurgical leaks (64.5%), iatrogenic perforations (19.6%), Boerhaave's syndrome (7.8%) and fistulae (3.7%). FC SEMS and partially covered SEMS were used in the majority of patients. Successful closure of the defect was achieved in 76.8% of patients and according to etiology in 81.4% for postsurgical leaks, 86.0% for perforations and 64.7% for fistulae. The pooled stent migration rate was 16.5%. Stent-related complications occurred in 13.4% of patients, including major (7.8%) and minor (5.5%) complications. The outcomes of stent placement for refractory benign esophageal strictures were poor. However, randomized trials are needed to put this into perspective. The evidence on successful stent placement for benign esophageal leaks, perforations and

  3. Multicenter trial evaluating the use of covered self-expanding metal stents in benign biliary strictures: time to revisit our therapeutic options?

    PubMed

    Kahaleh, Michel; Brijbassie, Alan; Sethi, Amrita; Degaetani, Marisa; Poneros, John M; Loren, David E; Kowalski, Thomas E; Sejpal, Divyesh V; Patel, Sandeep; Rosenkranz, Laura; McNamara, Kevin N; Raijman, Isaac; Talreja, Jayant P; Gaidhane, Monica; Sauer, Bryan G; Stevens, Peter D

    2013-09-01

    Covered self-expanding metal stents are being used more frequently in benign biliary strictures (BBS). We report the results of a multicenter study with fully covered self-expanding metal stent (FCSEMS) placement for the management of BBS. : To prospectively evaluate the efficacy and safety of FCSEMS in the management of BBS. Patients with BBS from 6 tertiary care centers who received FCSEMS with flared ends between April 2009 and October 2010 were included in this retrospective study.Efficacy was measured after removal of FCSEMS by evaluating stricture resolution on the basis of symptom resolution, imaging, laboratory studies, and/or choledochoscopy at removal. Safety profile was evaluated by assessing postprocedural complications. A total of 133 patients (78, 58.6% males) with a mean age of 59.2±14.8 years with BBS received stents. Of the 133 stents placed, 97 (72.9%) were removed after a mean stent duration of 95.5±48.7 days. Stricture resolution after FCSEMS removal was as follows: postsurgical, 11/12 (91.6%); gallstone-related disease, 16/19 (84.2%); chronic pancreatitis, 26/31 (80.7%); other etiology, 4/5 (80.0%); and anastomotic strictures, 19/31(61.2%). Ninety-four patients were included in the logistic regression analyses. Patients who had indwelling stents for >90 days were 4.3 times more likely to have resolved strictures [odds ratio, 4.3 (95% confidence interval, 1.24-15.09)] and patients with nonmigrated stents were 5.4 times more likely to have resolved strictures [odds ratio, 5.4 (95% confidence interval, 1.001-29.29)]. FCSEMS for BBS had an acceptable rate of stricture resolution for postsurgical strictures, gallstone-related strictures, and those due to chronic pancreatitis. Predictors for stricture resolution include longer indwell time and absence of migration. Further study is warranted to assess long-term efficacy in a prospective manner with longer than 3-month time of stent indwelling time.

  4. [Gastric outlet obstruction in malignant stenosis: self expanding metal stents].

    PubMed

    Jury, Gastón; Amieva, Leandro; Bouzas, Guillermo; López Fagalde, Rafael; Pili, Carlos; Ramacciotti, Gonzalo; Jury, Rubén

    2012-12-01

    Gastric outlet obstruction is a complication that can occur in the evolution of patients with pancreatic adenocarcinoma. Self-expanding metal stents (SEMS) resolve this situation by endoscopy, thus avoiding a laparoscopic gastroenterotomy. The aim of our study is to report our experience in the palliative treatment with SEMS of gastroduodenal neoplasic obstruction at a monovalent gastroenterology institute in Mar del Plata. All patients with symptoms of gastric outlet obstruction of neoplasic origin who fit for SEMS between January 2006 and February 2011 were included. Data were collected regarding the patients' clinical characteristics as well as the type of tumor and the efficacy of the procedure measured according to success and complication rates, length of hospital stay and evaluation of clinical benefit, according to performance status scales and gastric outlet obstruction score (GOOS). A total of 17 prosthesis placed in 16 patients were analyzed. In all cases the procedure was completed successfully. The intervention was performed on an outpatient basis in 12 patients (75%). One patient presented within 7 days gastric haemorrhage related with the stent, who was early treated with argon plasma. Late expected com- plications due to prolonged survival were observed in 60% of patients. None of them was serious and resolved spontaneously or by endoscopic treatment. Average survival was 117 days (range 3 to 300 days) and most patients showed subjective improvement in GOOS scale. SEMS have a high rate of technical and clinical success. However, they are scarcely known in our field. They present an insignificant number of early complications and the resolution of later ones is quite easy. An improvement in GOOS scale and quality of life is achieved.

  5. Randomized multicenter study of multiple plastic stents vs. covered self-expandable metallic stent in the treatment of biliary stricture in chronic pancreatitis.

    PubMed

    Haapamäki, Carola; Kylänpää, Leena; Udd, Marianne; Lindström, Outi; Grönroos, Juha; Saarela, Arto; Mustonen, Harri; Halttunen, Jorma

    2015-07-01

    The use of covered self-expandable metallic stents (cSEMS) in benign biliary indications is evolving. The aim of the study was to assess the safety and feasibility of cSEMS compared with multiple plastic stents in the treatment of benign biliary stricture (BBS) caused by chronic pancreatitis. This was a prospective, multicenter, randomized study of 60 patients with BBS caused by chronic pancreatitis. All patients received an initial plastic stent before randomization. At randomization, the stent was replaced either with a single cSEMS or three plastic stents. After 3 months, the position of the cSEMS was checked or another three plastic stents were added. At 6 months after randomization, all stents were removed. Clinical follow-up including abdominal ultrasound and laboratory tests were performed at 6 months and 2 years after stent removal. Two patients dropped out of the cSEMS group before stent removal. In April 2014, the median follow-up was 40 months (range 1 - 66 months). The 2-year, stricture-free success rate was 90 % (95 % confidence interval [CI] 72 % - 97 %) in the plastic stent group and 92 % (95 %CI 70 % - 98 %) in the cSEMS group (P = 0.405). There was one late recurrence in the plastic stent group 50 months after stent removal. Stent migration occurred three times (10 %) in the plastic stent group and twice in the cSEMS group (7 %; P = 1.000). A 6-month treatment with either six 10-Fr plastic stents or with one 10-mm cSEMS produced good long-term relief of biliary stricture caused by chronic pancreatitis.Study registered at ClinicalTrials.gov (NCT01085747). © Georg Thieme Verlag KG Stuttgart · New York.

  6. Self-expandable metal stents for malignant gastric outlet obstruction: A pooled analysis of prospective literature.

    PubMed

    van Halsema, Emo E; Rauws, Erik A J; Fockens, Paul; van Hooft, Jeanin E

    2015-11-21

    To provide an overview of the clinical outcomes of self-expandable metal stent (SEMS) placement for malignant gastric outlet obstruction (MGOO). A systematic literature search was performed in PubMed of the literature published between January 2009 and March 2015. Only prospective studies that reported on the clinical success of stent placement for MGOO were included. The primary endpoint was clinical success, defined according to the definition used in the original article. Data were pooled and analyzed using descriptive statistics. Subgroup analyses were performed for partially covered SEMSs (PCSEMSs) and uncovered SEMSs (UCSEMSs) using Fisher's exact test. A total of 19 studies, including 1281 patients, were included in the final analysis. Gastric (42%) and pancreatic (37%) cancer were the main causes of MGOO. UCSEMSs were used in 76% of patients and PCSEMSs in 24%. The overall pooled technical success rate was 97.3% and the clinical success rate was 85.7%. Stent dysfunction occurred in 19.6% of patients, mainly caused by re-obstruction (12.6%) and stent migration (4.3%), and was comparable between PCSEMSs and UCSEMSs (21.2% vs 19.1%, respectively, P = 0.412). Re-obstruction was more common with UCSEMSs (14.9% vs 5.1%, P < 0.001) and stent migration was more frequent after PCSEMS placement (10.9% vs 2.2%, P < 0.001). The overall perforation rate was 1.2%. Bleeding was reported in 4.1% of patients, including major bleeding in 0.8%. The median stent patency ranged from 68 to 307 d in five studies. The median overall survival ranged from 49 to 183 d in 13 studies. The clinical outcomes in this large population showed that enteral stent placement was feasible, effective and safe. Therefore, stent placement is a valid treatment option for the palliation of MGOO.

  7. Self-expandable metal stents for malignant gastric outlet obstruction: A pooled analysis of prospective literature

    PubMed Central

    van Halsema, Emo E; Rauws, Erik AJ; Fockens, Paul; van Hooft, Jeanin E

    2015-01-01

    AIM: To provide an overview of the clinical outcomes of self-expandable metal stent (SEMS) placement for malignant gastric outlet obstruction (MGOO). METHODS: A systematic literature search was performed in PubMed of the literature published between January 2009 and March 2015. Only prospective studies that reported on the clinical success of stent placement for MGOO were included. The primary endpoint was clinical success, defined according to the definition used in the original article. Data were pooled and analyzed using descriptive statistics. Subgroup analyses were performed for partially covered SEMSs (PCSEMSs) and uncovered SEMSs (UCSEMSs) using Fisher’s exact test. RESULTS: A total of 19 studies, including 1281 patients, were included in the final analysis. Gastric (42%) and pancreatic (37%) cancer were the main causes of MGOO. UCSEMSs were used in 76% of patients and PCSEMSs in 24%. The overall pooled technical success rate was 97.3% and the clinical success rate was 85.7%. Stent dysfunction occurred in 19.6% of patients, mainly caused by re-obstruction (12.6%) and stent migration (4.3%), and was comparable between PCSEMSs and UCSEMSs (21.2% vs 19.1%, respectively, P = 0.412). Re-obstruction was more common with UCSEMSs (14.9% vs 5.1%, P < 0.001) and stent migration was more frequent after PCSEMS placement (10.9% vs 2.2%, P < 0.001). The overall perforation rate was 1.2%. Bleeding was reported in 4.1% of patients, including major bleeding in 0.8%. The median stent patency ranged from 68 to 307 d in five studies. The median overall survival ranged from 49 to 183 d in 13 studies. CONCLUSION: The clinical outcomes in this large population showed that enteral stent placement was feasible, effective and safe. Therefore, stent placement is a valid treatment option for the palliation of MGOO. PMID:26604654

  8. Self-expandable metal stents for malignant esophageal obstruction: a comparative study between extrinsic and intrinsic compression.

    PubMed

    Rhee, K; Kim, J-H; Jung, D H; Han, J W; Lee, Y C; Lee, S K; Shin, S K; Park, J C; Chung, H S; Park, J J; Youn, Y H; Park, H

    2016-04-01

    Self-expandable metal stents (SEMSs) are effective for malignant esophageal obstruction, but usefulness of SEMSs in extrinsic lesions is yet to be elucidated. This study is aimed at evaluating the clinical usefulness of SEMSs in the extrinsic compression compared with intrinsic. A retrospective review was conducted for 105 patients (intrinsic, 85; extrinsic, 20) with malignant esophageal obstruction who underwent endoscopic SEMSs placement. Technical and clinical success rates were evaluated and clinical outcomes were compared between extrinsic and intrinsic group. Extrinsic group was mostly pulmonary origin. Overall technical and clinical success rate was 100% and 91%, respectively, without immediate complications. Extrinsic and intrinsic group did not differ significantly in clinical success rate. The median stent patency time was 131.3 ± 85.8 days in intrinsic group while that of extrinsic was 54.6 ± 45.1 due to shorter survival after stent insertion. The 4-, 8-, and 12-week patency rates were 90.5%, 78.8%, and 64.9% respectively in intrinsic group, while stents of extrinsic group remained patent until death. Uncovered, fully covered, and double-layered stent were used evenly and the types did not influence patency in both groups. In conclusion, esophageal SEMSs can safely and effectively be used for malignant extrinsic compression as well as intrinsic. © 2015 International Society for Diseases of the Esophagus.

  9. Successful management of benign biliary strictures with fully covered self-expanding metal stents.

    PubMed

    Devière, Jacques; Nageshwar Reddy, D; Püspök, Andreas; Ponchon, Thierry; Bruno, Marco J; Bourke, Michael J; Neuhaus, Horst; Roy, André; González-Huix Lladó, Ferrán; Barkun, Alan N; Kortan, Paul P; Navarrete, Claudio; Peetermans, Joyce; Blero, Daniel; Lakhtakia, Sundeep; Dolak, Werner; Lepilliez, Vincent; Poley, Jan W; Tringali, Andrea; Costamagna, Guido

    2014-08-01

    Fully covered self-expanding metal stents (FCSEMS) are gaining acceptance for the treatment of benign biliary strictures. We performed a large prospective multinational study to study the ability to remove these stents after extended indwell and the frequency and durability of stricture resolution. In a nonrandomized study at 13 centers in 11 countries, 187 patients with benign biliary strictures received FCSEMS. Removal was scheduled at 10-12 months for patients with chronic pancreatitis or cholecystectomy and at 4-6 months for patients who received liver transplants. The primary outcome measure was removal success, defined as either scheduled endoscopic removal of the stent with no removal-related serious adverse events or spontaneous stent passage without the need for immediate restenting. Endoscopic removal of FCSEMS was not performed for 10 patients because of death (from unrelated causes), withdrawal of consent, or switch to palliative treatment. For the remaining 177 patients, removal success was accomplished in 74.6% (95% confidence interval [CI], 67.5%-80.8%). Removal success was more frequent in the chronic pancreatitis group (80.5%) than in the liver transplantation (63.4%) or cholecystectomy (61.1%) groups (P = .017). FCSEMS were removed by endoscopy from all patients in whom this procedure was attempted. Stricture resolution without restenting upon FCSEMS removal occurred in 76.3% of patients (95% CI, 69.3%-82.3%). The rate of resolution was lower in patients with FCSEMS migration (odds ratio, 0.22; 95% CI, 0.11-0.46). Over a median follow-up period of 20.3 months (interquartile range, 12.9-24.3 mo), the rate of stricture recurrence was 14.8% (95% CI, 8.2%-20.9%). Stent- or removal-related serious adverse events, most often cholangitis, occurred in 27.3% of patients. There was no stent- or removal-related mortality. In a large prospective multinational study, removal success of FCSEMS after extended indwell and stricture resolution were achieved for

  10. Lumen-apposing covered self-expandable metal stents for short benign gastrointestinal strictures: a multicenter study.

    PubMed

    Yang, Dennis; Nieto, Jose M; Siddiqui, Ali; Riff, Brian P; DiMaio, Christopher J; Nagula, Satish; Ismail, Amr M; Ngamreungphong, Saowanee; Khashab, Mouen A; Wagh, Mihir S; Tzimas, Demetrios; Buscaglia, Jonathan M; Strand, Daniel S; Wang, Andrew Y; Chauhan, Shailendra S; Forsmark, Christopher E; Draganov, Peter V

    2017-04-01

    Background and study aim  Use of the fully covered self-expandable metal stent (SEMS) for benign luminal gastrointestinal (GI) stricture (BLGS) has been limited by the migration rate. The role of the lumen-apposing metal stent (LAMS) for BLGS is not well defined. We assessed the safety, feasibility, and efficacy of LAMS for the treatment of BLGS. Patients and methods  This was an observational, open-label, retrospective, single-arm, multicenter consecutive case series of patients undergoing LAMS placement for BLGS. Technical success was defined as successful placement of the LAMS. Short- and long-term clinical success rates were defined as symptom improvement/resolution with indwelling stent and after stent removal, respectively. All adverse events and additional interventions were recorded. Results  A total of 30 patients (mean age 51.6 years; 63.3 % women) underwent LAMS placement for GI strictures (83.9 % anastomotic). Median stricture diameter and length were 4.5 mm (range 2 - 10 mm) and 8 mm (range 5 - 10 mm), respectively. Technical success was achieved in 29 patients (96.7 %), with an adverse event rate of 13.3 %. The stent migration rate was 8.0 % (2/25) on follow-up endoscopy. Short-term clinical success was achieved in 90.0 % (27/30) at a median of 60 days (interquartile range [IQR] 40 - 90 days). Most patients (19/23; 82.6 %) experienced sustained symptom improvement/resolution without the need for additional interventions at a median follow-up of 100 days (IQR 60 - 139 days) after LAMS removal. Conclusion  This multicenter study demonstrated that LAMS placement represents a safe, feasible, and effective therapeutic option for patients with BLGS and is associated with a low stent migration rate. Our initial findings suggest that future prospective comparative studies are needed on the use of LAMS, endoscopic dilation, and conventional SEMS. . © Georg Thieme Verlag KG Stuttgart · New York.

  11. Treatment of cuff-related tracheal stenosis with a fully covered retrievable expandable metallic stent.

    PubMed

    Chen, G; Wang, Z; Liang, X; Wang, Y; Wang, Y; Wang, Z; Xian, J

    2013-04-01

    To investigate the clinical effectiveness, complications, and optimal duration of use of covered retrievable expandable metallic stents in the management of cuff-related tracheal stenosis. Twenty-one patients with cuff-related tracheal stenosis, Meyer-Cotton grade II (29%) and III (71%), who underwent fluoroscopically guided placement of covered retrievable expandable metallic stents were studied. Sixty-four-section computed tomography (CT) and bronchovideoscopy were performed prior to stent insertion, 1 month after stent insertion, in the case of stent-related complications, and after stent removal. Clinical manifestations, Hugh-Jones classification, and forced expiratory volume in 1 s (FEV1) were used to evaluate respiratory function before and after stent insertion and removal. The diameter of the stricture and FEV1 changes before insertion and after removal were analysed using the paired samples t-test. A p-value of ≤0.05 was considered statistically significant. Twenty-one patients had 27 covered retrievable expandable metallic stents placed. Stents were electively removed from 20 patients. The median duration of stent placement was 5 months (range 4-12 months). One stent was not removed due to mucopolysaccharidosis type II (MPS II or Hunter syndrome) with tracheomalacia. After stent removal, airway dimensions increased and airway occlusion was symptomatically relieved in all patients. CT and bronchovideoscopy showed patent lumens with increased dimensions. Stent-related complications occurred in 19 (91%) patients, including granulation tissue formation (n = 18, 86%), stent migration and stent expectoration (n = 2, 10%), mucus plugging (n = 1, 5%), and halitosis (n = 6, 29%). Some patients experienced multiple complications, which were all managed effectively while the stent was still in place. There was a statistically significant difference in the diameter of the stricture and FEV1 between the time of stent insertion and removal. An improvement in

  12. Palliative self-expandable metal stents for acute malignant colorectal obstruction: clinical outcomes and risk factors for complications.

    PubMed

    Han, Jae Pil; Hong, Su Jin; Kim, Shin Hee; Choi, Jong Hyo; Jung, Hee Jae; Cho, Youn Hee; Ko, Bong Min; Lee, Moon Sung

    2014-08-01

    Self-expandable metal stents (SEMSs) have been used as palliative treatment or bridge to surgery for obstructions caused by colorectal cancer (CRC). We assessed the long-term outcomes of palliative SEMSs and evaluated the risk factors influencing complications. One hundred and seventy-five patients underwent SEMS placement for acute malignant colorectal obstruction. Of the 72 patients who underwent palliative treatment for primary CRC, 30 patients received chemotherapy (CT) for primary cancer (CT group) and 42 underwent best supportive treatment (BST) without CT (BST group). There was a significant difference in late migration between the CT group and the BST group (20.0% in CT group, 2.4% in BST group, p = 0.018). Response to CT influenced the rate of late obstruction (0% in disease control, 35.7% in disease progression, p = 0.014). However, late obstruction was not associated with stent properties, such as diameter or type (≤22 mm vs. >22 mm, 13.5% vs. 14.3%, p = 1.00; uncovered stent vs. covered stent, 15.5% vs. 7.1%, p = 0.675) and migration (≤22 mm vs. >22 mm, 16.2% vs. 2.9%, p = 0.108; uncovered stent vs. covered stent, 8.6% vs. 14.3%, p = 0.615) in palliative SEMS. The administration of CT increases the rate of stent migration, and disease control by CT can reduce the risk of obstruction by maintaining the luminal patency of palliative SEMSs.

  13. Use of nitinol self-expandable stents in 26 dogs with tracheal collapse.

    PubMed

    Beranek, J; Jaresova, H; Rytz, U

    2014-02-01

    A study was designed to describe a novel approach to the treatment of tracheal collapse (TC) in dogs using self-expandable nitinol stents. Medical records were reviewed retrospectively for 26 client owned dogs in which nitinol stents were deployed. The entire length of trachea was supported independently of the extent of TC. Two overlapping stents were used instead of one in cases where one stent was not spanning the entire trachea adequately. The diameter of the cranial radiolucent portion of trachea, just behind the cricoid cartilage, was measured as a specific landmark to select the appropriate size of the stent. Two self-expandable nitinol stents were inserted in 9 of 26 dogs; the trachea in the rest of the cases was supported with only one stent. A follow up tracheoscopy was performed in 10 of 26 cases with recurrent clinical signs. Secondary tracheal stenosis in these cases was caused by stent fracture, granuloma or excessive stent shortening. Additional stents were placed successfully to expand the stenotic lumen. A support of the entire trachea may decrease risk of nitinol fracture at the end of the implant. Long term clinical improvement (25 of 26 dogs, 96 %) is comparable with the results of other studies.

  14. Short-Term Use of Uncovered Self-Expanding Metallic Airway Stents for Severe Expiratory Central Airway Collapse.

    PubMed

    Majid, Adnan; Alape, Daniel; Kheir, Fayez; Folch, Erik; Ochoa, Sebastian; Folch, Alejandro; Gangadharan, Sidhu P

    2016-01-01

    Patients with severe symptomatic expiratory central airway collapse (ECAC) undergo a stent trial to determine whether they are candidate for tracheobronchoplasty. Most stent trials were done using silicone stents. However, there was a higher number of silicone stent-related complications. The aim of this study was to evaluate the safety and efficacy of short-term uncovered self-expanding metallic airway stents (USEMAS) in patients with ECAC. This was a retrospective review. Baseline measurements were compared to those obtained after 7-14 days. Measurements included: Modified Medical Research Council (mMRC), Cough Quality of Life Questionnaire (CQLQ), spirometry testing, and 6-Minute Walk Test (6MWT). Stent- and procedure-related complications were reported. 33 patients (median age, 52 years) underwent the USEMAS trial. Presenting symptoms were dyspnea in 100%, intractable cough in 90.3%, recurrent infection in 42.2%, and inability to clear secretions in 21.4%. Dyspnea, cough, and secretion clearance improved in 88, 70, and 57%, respectively. Overall, there was a significant improvement in mMRC (p < 0.001), CQLQ (p = 0.015), and 6MWT (p = 0.015). There was 1 airway infection, 1 stent migration, and 1 pneumothorax. The median duration of USEMAS was 7 days. All stents were removed without any complications. At the time of stent removal, no granulation tissue was observed in 30.9%, and mild granulation tissue was observed in 69.1%. The short-term USEMAS trial improves respiratory symptoms, quality of life, and exercise capacity with few complications in patients with severe symptomatic ECAC when performed by a multidisciplinary airway team in highly specialized centers with experience in the evaluation and treatment of this patient population. © 2016 S. Karger AG, Basel.

  15. A New Fully Covered Self-Expandable Metal Stent for the Treatment of Postsurgical Benign Biliary Strictures.

    PubMed

    Wu, Jun; Zhou, Dong-Xun; Wang, Tian-Tian; Gao, Dao-Jian; Hu, Bing

    2017-09-01

    Endotherapy with plastic stent (PS) placement is the main modality for treating benign biliary strictures (BBSs). Fully covered self-expandable metal stents (FCSEMSs) are being increasingly used for BBS management, with high stricture resolution. However, traditional metal tents are associated with high migration, causing treatment failure. We investigated the efficacy and safety of a new FCSEMS for postsurgical BBS treatment and compared these parameters between the FCSEMS and PS treatment through retrospective analysis. The primary outcome measurements included stricture resolution, stricture recurrence, and complications. In total, 69 patients were included, of whom 32 underwent FCSEMS treatment and 37 underwent PS treatment. The technical success rate and the number of endoscopic retrograde cholangiopancreatography procedures were similar between the groups. The median stenting duration was 5.2 months (range 1.5-15.3) in the FCSEMS group and 10.7 months (range 2.5-22.6) in the PS group (P < 0.01). The stents removal rate was 96.9% in the FCSEMS group and 94.6% in the PS group. The stricture resolution rate based on intention-to-treat analysis was 83.8% in the PS group and 84.4% (27/32) in the FCSEMS group (P = 0.947), whereas the rates from per-protocol analysis were 88.6% (31/35) and 87.1% (27/31), respectively (P = 0.574). Early and late complications were similar between the groups. The median follow-up time was 43 months (range 13-71). The stricture recurrence rate was 11.1% (3/27) in the FCSEMS group and 16.1% (5/31) in the PS group (P = 0.435). The new FCSEMS and the PS approach showed similar efficacy and safety in postsurgical BBS treatment. However, the FCSEMS required fewer procedural steps and shorter stenting time, making it an effective alternative modality.

  16. Nitinol versus steel partially covered self-expandable metal stent for malignant distal biliary obstruction: a randomized trial.

    PubMed

    Soderlund, Claes; Linder, Stefan; Bergenzaun, Per E; Grape, Tomas; Hakansson, Hans-Olof; Kilander, Anders; Lindell, Gert; Ljungman, Martin; Ohlin, Bo; Nielsen, Jorgen; Rudberg, Claes; Stotzer, Per-Ove; Svartholm, Erik; Toth, Ervin; Frozanpor, Farshad

    2014-11-01

    Covered nitinol alloy self-expandable metal stents (SEMSs) have been developed to overcome the shortcomings of steel SEMS in patients with malignant biliary obstruction. In a randomized, multicenter trial, we compared stent patency, patient survival, and adverse events in patients with partly covered stents made from steel or nitinol. A total of 400 patients with unresectable distal malignant biliary obstruction were randomized at endoscopic retrograde cholangiopancreatography (ERCP) to insertion of a steel or nitinol partially covered SEMS, with 200 patients in each group. The primary outcome was confirmed stent failure during 300 days of follow-up.  At 300 days, the proportion of patients with patent stents was 77 % in the steel group, compared with 89 % in the nitinol group (P = 0.01). Confirmed stent failure occurred more often in the steel SEMS group compared with the nitinol SEMS group, in 30 versus 14 patients (P = 0.02). Stent migration occurred in 13 patients in the steel group and in 3 patients in the nitinol group (P = 0.01). Median patient survival (secondary outcome) was 137 days and 120 days in the steel SEMS and nitinol SEMS groups, respectively (P = 0.59). The nitinol SEMS showed longer patency time, and the nitinol group had fewer patients with stent failure, compared with the steel SEMS group. We could not detect any differences between the two groups regarding survival time, and regarding adverse event rate.Clinical trial registration : NCT 00980889. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Treatment of congenital tracheal stenosis by balloon-expandable metallic stents in paediatric intensive care unit

    PubMed Central

    Xu, Xuan; Li, Dandan; Zhao, Shuyu; Liu, Xicheng; Feng, Zhichun; Ding, Hui

    2012-01-01

    The aim of this study was to evaluate the use of balloon-expandable metallic stents in the treatment of children with congenital tracheal stenosis in whom conventional therapy has failed. From 2010 to 2011, balloon-expandable metallic stents were implanted into the trachea of eight infants aged 2–20 months in the paediatric intensive care unit. The infants had severe airway obstruction caused by congenital tracheal stenosis. Tracheal stents were placed after intraluminal balloon dilatation of the tracheal stenosis, inserted with balloon catheters and implanted into the desired position bronchoscopically. The stents were 12 to 29 mm long and 4 mm in diameter. Seven children were relieved of airway obstruction after this procedure. However, a child died due to severe sepsis after the placement of bronchial stents. No granulation tissue developed over the stents in any of the children. Stents have been in place for 1–6 months after insertion without any other complication. Balloon-expandable metallic stents are effective in relieving airway obstruction by congenital tracheal stenosis in children. This technique may provide an important remedy for congenital tracheal stenosis in children. PMID:22361127

  18. Application of Y-shaped, coated self-expandable metallic stents for anastomotic stenosis after gastrojejunostomy (Billroth II).

    PubMed

    Li, Teng-Fei; Wu, Gang; Han, Xin-Wei; Shui, Shao-Feng; Ren, Jian-Zhuang; Li, Zhen; Ren, Ke-Wei

    2017-01-01

    Anastomotic stenosis is an infrequent but life-threatening complication after gastrojejunostomy (Billroth II). Tubular or single tubular stents have limited efficacy due to the particular anatomy. To assess the feasibility of a Y-shaped, fully-coated, self-expandable, metallic stent (SEMS) for anastomotic stenosis after gastrojejunostomy (Billroth II). Between January 2008 and August 2014, 14 patients (10 with gastric carcinoma and four with duodenal ulcers) had anastomotic stenoses following Billroth II reconstructions. Eight patients with gastric cancer had tumor recurrence near the anastomosis; two had benign strictures. The four duodenal ulcer patients had benign stenoses. An integrated Y-shaped, fully coated SEMS was designed to accord with the anatomy of residual gastrojejunal anastomotic strictures. Fourteen stents were inserted under fluoroscopic control. Follow-up was at 1, 3, 9, and 12 months, and then annually. All 14 stents were inserted successfully at the first attempt with a technical success rate of 100%. After stenting, abdominal symptoms resolved in all patients. All patients were followed up for 4-27 months (mean, 13.9 months). One of the eight recurrent cases died of multiple tumor metastases and liver failure after 7 months, without obstruction symptoms. In all six patients with benign anastomotic stenosis, the stents were removed successfully without complication and with no evidence of restenosis based on clinical evaluation and imaging. A Y-shaped, fully-coated SEMS proved to be a feasible and minimally invasive procedure for treating anastomotic stenosis after gastrojejunostomy (Billroth II). © The Foundation Acta Radiologica 2016.

  19. Treatment of benign biliary leaks with transhepatic placement of coated self-expanding metallic stents.

    PubMed

    Páramo, M; García-Barquín, P; Carrillo, M; Millor Muruzábal, M; Vivas, I; Bilbao, J I

    To analyze the safety and efficacy of percutaneous placement of coated self-expanding metallic stents (SEMS) in patients with biliary leaks. This ethics committee at our center approved this study. We retrospectively reviewed all coated SEMS placed between October 2008 and September 2015. We analyzed patient-related factors such as the primary underlying disease, prior hepatic procedures, and clinical outcome. We evaluated the location, the number and type of leak (anastomotic or non-anastomotic), and the characteristics of the interventional procedure (number of stents deployed, location of the stents, technical success, and primary functionality). We recorded the complications registered. We studied 14 patients (11 men and 3 women). The mean follow-up period was 375.5 days (range 15-1920 days). Leaks were postsurgical in 12 patients. One patient developed an arteriobilioportal fistula. In another, the biliary leak occurred secondary to the rupture of the common bile duct after ERCP. A total of 23 coated SEMS were placed, including 21 Fluency ® stents (Bard, Tempe, AZ, USA) and 2 Wallflex ® stents (Boston Scientific, Galway, Republic of Ireland). The technical success of the procedure was considered total in 11 (78.6%) patients, partial in 2 (14.3%) patients, and null in 1 (7.2%) patient. The clinical outcome was good in 13 of the 14 patients. The mean period of primary functionality of the coated SEMS was 331 days (range 15-1920 days). No major complications were observed in 11 (78.6%) patients. Percutaneous placement of coated SEMS for the treatment of benign biliary leaks is safe and efficacious, with a high rate of technical and clinical success and a moderate rate of complications. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Alteration of intraaneurysmal hemodynamics by placement of a self-expandable stent. Laboratory investigation.

    PubMed

    Tateshima, Satoshi; Tanishita, Kazuo; Hakata, Yasuhiro; Tanoue, Shin-ya; Viñuela, Fernando

    2009-07-01

    Development of a flexible self-expanding stent system and stent-assisted coiling technique facilitates endovascular treatment of wide-necked brain aneurysms. The hemodynamic effect of self-expandable stent placement across the neck of a brain aneurysm has not been well documented in patient-specific aneurysm models. Three patient-specific silicone aneurysm models based on clinical images were used in this study. Model 1 was constructed from a wide-necked internal carotid artery-ophthalmic artery aneurysm, and Models 2 and 3 were constructed from small wide-necked middle cerebral artery aneurysms. Neuroform stents were placed in the in vitro aneurysm models, and flow structures were compared before and after the stent placements. Flow velocity fields were acquired with particle imaging velocimetry. In Model 1, a clockwise, single-vortex flow pattern was observed in the aneurysm dome before stenting was performed. There were multiple vortices, and a very small fast flow stream was newly formed in the aneurysm dome after stenting. The mean intraaneurysmal flow velocity was reduced by approximately 23-40%. In Model 2, there was a clockwise vortex flow in the aneurysm dome and another small counterclockwise vortex in the tip of the aneurysm dome before stenting. The small vortex area disappeared after stenting, and the mean flow velocity in the aneurysm dome was reduced by 43-64%. In Model 3, a large, counterclockwise, single vortex was seen in the aneurysm dome before stenting. Multiple small vortices appeared in the aneurysm dome after stenting, and the mean flow velocity became slower by 22-51%. The flexible self-expandable stents significantly altered flow velocity and also flow structure in these aneurysms. Overall flow alterations by the stent appeared favorable for the long-term durability of aneurysm embolization. The possibility that the placement of a low-profile self-expandable stent might induce unfavorable flow patterns such as a fast flow stream in the

  1. Full covered self-expandable metal stents for the treatment of anastomotic leak using a silk thread

    PubMed Central

    Choi, Cheol Woong; Kang, Dae Hwan; Kim, Hyung Wook; Park, Su Bum; Kim, Su Jin; Hwang, Sun Hwi; Lee, Si Hak

    2017-01-01

    Abstract To evaluate the safety and effectiveness of fixation of the fully covered self-expandable metal stent (SEMS) placement using a silk thread for complete closure of an anastomotic leak. An anastomotic leak is a life-threatening complication after gastrectomy. Although the traditional treatment of choice was surgical re-intervention, an endoscopic SEMS can be used alternatively. During the study period, we retrospectively reviewed consecutive patients who received a modified covered SEMS capable of being fixed using a silk thread (Shim technique) due to an anastomotic leak after gastrectomy to prevent stent migration. Demographic data, stent placement and removal, clinical success, time to resolution, and complications were evaluated. A total of 7 patients underwent fully covered SEMS with a silk thread placement for an anastomotic leak after gastrectomy to treat gastric cancer. The patients’ mean age was 71.3 ± 8.0 years. Man sex was predominant (85.7%). All patients’ American Society of Anesthesiologists (ASA) scores were between I and III. Total gastrectomy was performed in 5 patients (71.4%) and proximal gastrectomy was performed in 2 patients (28.6%). The time between gastrectomy and stent insertion was 22.3 ± 11.1 days. The size of the leaks was 27.1 ± 11.1 mm. Technical success and complete leak closure were achieved in all patients. Stent migration was absent. All stents were removed between 4 and 6 weeks. Delayed esophageal stricture was found in 1 patient (14.2) and successfully resolved after endoscopic balloon dilation. For an anastomotic leak after gastrectomy, fully covered SEMS placement with a silk thread is an effective and safe treatment option without stent migration. The stent extraction time between 4 and 6 weeks was optimal without severe complications. PMID:28723752

  2. Full covered self-expandable metal stents for the treatment of anastomotic leak using a silk thread.

    PubMed

    Choi, Cheol Woong; Kang, Dae Hwan; Kim, Hyung Wook; Park, Su Bum; Kim, Su Jin; Hwang, Sun Hwi; Lee, Si Hak

    2017-07-01

    To evaluate the safety and effectiveness of fixation of the fully covered self-expandable metal stent (SEMS) placement using a silk thread for complete closure of an anastomotic leak. An anastomotic leak is a life-threatening complication after gastrectomy. Although the traditional treatment of choice was surgical re-intervention, an endoscopic SEMS can be used alternatively.During the study period, we retrospectively reviewed consecutive patients who received a modified covered SEMS capable of being fixed using a silk thread (Shim technique) due to an anastomotic leak after gastrectomy to prevent stent migration. Demographic data, stent placement and removal, clinical success, time to resolution, and complications were evaluated.A total of 7 patients underwent fully covered SEMS with a silk thread placement for an anastomotic leak after gastrectomy to treat gastric cancer. The patients' mean age was 71.3 ± 8.0 years. Man sex was predominant (85.7%). All patients' American Society of Anesthesiologists (ASA) scores were between I and III. Total gastrectomy was performed in 5 patients (71.4%) and proximal gastrectomy was performed in 2 patients (28.6%). The time between gastrectomy and stent insertion was 22.3 ± 11.1 days. The size of the leaks was 27.1 ± 11.1 mm. Technical success and complete leak closure were achieved in all patients. Stent migration was absent. All stents were removed between 4 and 6 weeks. Delayed esophageal stricture was found in 1 patient (14.2) and successfully resolved after endoscopic balloon dilation.For an anastomotic leak after gastrectomy, fully covered SEMS placement with a silk thread is an effective and safe treatment option without stent migration. The stent extraction time between 4 and 6 weeks was optimal without severe complications.

  3. Self-expanding metal mesh stents and laser therapy: a complementary approach for the palliation of malignant dysphagia

    NASA Astrophysics Data System (ADS)

    Madhotra, Ravi; Raouf, A.; Sturgess, R.; Krasner, Neville

    1997-12-01

    Re-establishment of the oesophageal lumen is the main focus of care in patients with inoperable oesophageal carcinomas. The self-expanding metal mesh stents (MMS) are increasingly being used. 51 patients aged 44 - 89 with inoperable oesophago-gastric carcinomas were intubated with MMS. 18 of these patients had endoscopic laser therapy (ELT) as primary palliation. 25 patients required follow-up endoscopy at variable intervals after stent insertion. 17 patients were found to have significant tumor growth (9), overgrowth (4) and both (4). All these patients were treated with Nd:YAG or diode laser for maintenance of satisfactory swallowing. 4 patients being treated with Nd:YAG laser developed deformity of MMS. This complication was not encountered with diode laser. The reblockage of MMS due to ingrowth or overgrowth of tumor is a not uncommon complication. The timing of the stent insertion should be carefully chosen since the longer the stent is in situ, the greater is the likelihood of tumor ingrowth or overgrowth. ELT can effectively deal with tumor ingrowth and overgrowth. Nd:YAG laser can cause melting of MMS. Overall the combination of ELT and MMS may offer the best palliation, particularly when patient survival of several months is anticipated.

  4. Fabrication of balloon-expandable self-lock drug-eluting polycaprolactone stents using micro-injection molding and spray coating techniques.

    PubMed

    Liu, Shih-Jung; Chiang, Fu-Jun; Hsiao, Chao-Ying; Kau, Yi-Chuan; Liu, Kuo-Sheng

    2010-10-01

    The purpose of this report was to develop novel balloon-expandable self-lock drug-eluting poly(ε-caprolactone) stents. To fabricate the biodegradable stents, polycaprolactone (PCL) components were first fabricated by a lab-scale micro-injection molded machine. They were then assembled and hot-spot welded into mesh-like stents of 3 and 5 mm in diameters. A special geometry of the components was designed to self-lock the assembled stents and to resist the external pressure of the blood vessels after being expanded by balloons. Characterization of the biodegradable PCL stents was carried out. PCL stents exhibited comparable mechanical property to that of metallic stents. No significant collapse pressure reduction and weight loss of the stents were observed after being submerged in PBS for 12 weeks. In addition, the developed stent was coated with paclitaxel by a spray coating technique and the release characteristic of the drug was determined by an in vitro elution method. The high-performance liquid chromatography analysis showed that the biodegradable stents could release a high concentration of paclitaxel for more than 60 days. By adopting the novel techniques, we will be able to fabricate biodegradable drug-eluting PCL stents of different sizes for various cardiovascular applications.

  5. Assessment of safety and efficacy of an indigenous self-expandable fully covered esophageal metal stent for palliation of esophageal cancer.

    PubMed

    Padhan, R K; Nongthombam, S K; Venuthurimilli, A; Dhingra, R; Sahni, P; Garg, P K

    2016-01-01

    Patients with unresectable esophageal cancer require palliation for dysphagia. Placement of a self-expandable metal stent (SEMS) is the procedure of choice for palliation of dysphagia. To evaluate the safety and efficacy of an indigenous fully-covered SEMS in patients with esophageal cancer. Eligible patients with unresectable esophageal cancer requiring palliation for dysphagia were included in the study. An indigenous fully covered SEMS of appropriate length was placed under endoscopic and fluoroscopic guidance. Outcome measures assessed were adverse events and improvement in dysphagia. Twenty one patients (mean age 57.71±13.14 years; 17 males) were included. After stenting, dysphagia score decreased from 3.2+0.4 to 0.35+0.74 at 4 weeks. Adverse events included retrosternal pain, respiratory distress and aspiration pneumonia in 12, 2 and 1 patients respectively. Five patients required repeat stenting due to stent migration in 4 (following radiotherapy in 3) and tumour ingrowth in 1. There was primary stent malfunction in one patient. The median survival of patients was 140 (76-199) days, which was higher in those who received radiotherapy. The stent was reasonably safe and effective to relieve dysphagia due to unresectable esophageal cancer.

  6. Stent migration following endoscopic suture fixation of esophageal self-expandable metal stents: a systematic review and meta-analysis.

    PubMed

    Law, Ryan; Prabhu, Anoop; Fujii-Lau, Larissa; Shannon, Carol; Singh, Siddharth

    2018-02-01

    Covered self-expandable metal stents (SEMS) are utilized for the management of benign and malignant esophageal conditions; however, covered SEMS are prone to migration. Endoscopic suture fixation may mitigate the migration risk of covered esophageal SEMS. Hence, we conducted a systematic review and meta-analysis to evaluate the effectiveness and safety of endoscopic suture fixation for covered esophageal SEMS. Following PRISMA guidelines, we performed a systematic review from 2011 to 2016 to identify studies (case control/case series) reporting the technical success and migration rate of covered esophageal SEMS following endoscopic suture fixation. We searched multiple electronic databases and conference proceedings. We calculated pooled rates (and 95% confidence intervals [CI]) of technical success and stent migration using a random effects model. We identified 14 studies (212 patients) describing covered esophageal SEMS placement with endoscopic suture fixation. When reported, SEMS indications included leak/fistula (n = 75), stricture (n = 65), perforation (n = 10), and achalasia (n = 4). The pooled technical success rate was 96.7% (95% CI 92.3-98.6), without heterogeneity (I 2  = 0%). We identified 29 SEMS migrations at rate of 15.9% (95% CI 11.4-21.6), without heterogeneity (I 2  = 0%). Publication bias was observed, and using the trim-and-fill method, a more conservative estimate for stent migration was 17.0%. Suture-related adverse events were estimated to occur in 3.7% (95% CI 1.6-8.2) of cases. Endoscopic suture fixation of covered esophageal SEMS appears to reduce stent migration when compared to published rates of non-anchored SEMS. However, SEMS migration still occurs in approximately 1 out of 6 cases despite excellent immediate technical success and low risk of suture-related adverse events.

  7. Endoscopic suture fixation is associated with reduced migration of esophageal fully covered self-expandable metal stents (FCSEMS).

    PubMed

    Wright, Andrew; Chang, Andrew; Bedi, Aarti Oza; Wamsteker, Erik-Jan; Elta, Grace; Kwon, Richard S; Carrott, Phillip; Elmunzer, B Joseph; Law, Ryan

    2017-09-01

    Esophageal fully covered self-expandable metal stents (FCSEMS) are indicated for the management of benign and malignant conditions of the esophagus including perforations, leaks, and strictures. FCSEMS are resistant to tissue ingrowth and are removable; however, stent migration occurs in 30-55% of cases. Endoscopic suture fixation of FCSEMS has been utilized to decrease the risk of stent migration though data supporting this practice remain limited. The primary aim of this study was to compare clinical outcomes and migration rate of patients who underwent placement of esophageal FCSEMS with and without endoscopic suture fixation. Our single-center, retrospective, cohort study includes patients who underwent esophageal FCSEMS placement with and without endoscopic suture fixation between January 1, 2012, and November 11, 2015. Baseline patient characteristics, procedural details, and clinical outcomes were abstracted. Logistic regression was performed to identify clinical and technical factors associated with outcomes and stent migration. A total of 51 patients underwent 62 FCSEMS placements, including 21 procedures with endoscopic suture fixation and 41 without. Suture fixation was associated with reduced risk of stent migration (OR 0.13, 95% CI 0.03-0.47). Prior stent migration was associated with significantly higher risk of subsequent migration (OR 6.4, 95% CI 1.6-26.0). Stent migration was associated with lower likelihood of clinical success (OR 0.21, 95% CI 0.06-0.69). There was a trend toward higher clinical success among patients undergoing suture fixation (85.7 vs. 60.9%, p = 0.07). Endoscopic suture fixation of FCSEMS was associated with a reduced stent migration rate. Appropriate patient selection for suture fixation of FCSEMS may lead to reduced migration in high-risk patients.

  8. Self-expanding metallic stents drainage for acute proximal colon obstruction

    PubMed Central

    Yao, Li-Qin; Zhong, Yun-Shi; Xu, Mei-Dong; Xu, Jian-Min; Zhou, Ping-Hong; Cai, Xian-Li

    2011-01-01

    AIM: To clarify the usefulness of the self-expanding metallic stents (SEMS) in the management of acute proximal colon obstruction due to colon carcinoma before curative surgery. METHODS: Eighty-one colon (proximal to spleen flex) carcinoma patients (47 males and 34 females, aged 18-94 years, mean = 66.2 years) treated between September 2004 and June 2010 for acute colon obstruction were enrolled to this study, and their clinical and radiological features were reviewed. After a cleaning enema was administered, urgent colonoscopy was performed. Subsequently, endoscopic decompression using SEMS placement was attempted. RESULTS: Endoscopic decompression using SEMS placement was technically successful in 78 (96.3%) of 81 patients. Three patients’ symptoms could not be relieved after SEMS placement and emergent operation was performed 1 d later. The site of obstruction was transverse colon in 18 patients, the hepatic flex in 42, and the ascending colon in 21. Following adequate cleansing of the colon, patients’ abdominal girth was decreased from 88 ± 3 cm before drainage to 72 ± 6 cm 7 d later, and one-stage surgery after 8 ± 1 d (range, 7-10 d) was performed. No anastomotic leakage or postoperative stenosis occurred after operation. CONCLUSION: SEMS placement is effective and safe in the management of acute proximal colon obstruction due to colon carcinoma, and is considered as a bridged method before curative surgery. PMID:21876623

  9. Novel self-expandable, stent-based transcatheter pulmonic valve: a preclinical animal study.

    PubMed

    Kim, Gi Beom; Lim, Hong-Gook; Kim, Yong Jin; Choi, Eun Young; Kwon, Bo Sang; Jeong, Saeromi

    2014-04-15

    Because transcatheter implantation of pulmonary valve is indicated for limited-size dysfunctional right ventricular outflow tract only as a balloon-expandable stent, we investigated the feasibility of a large-diameter self-expandable valved stent and the durability of the valve after >6 months. We made a nitinol-wire-based, self-expandable valved stent with leaflets made from porcine pericardium. The porcine pericardium was treated with α-galactosidase, glutaraldehyde, and glycine after decellularization. After cutting the inguinal or cervical area, we implanted a valved stent in 12 sheep through the femoral or jugular vein by using an 18-Fr delivery catheter, controlling the catheter handles and hook block under fluoroscopic and echocardiographic guidance. The mean body weight of sheep was 43.9 kg. We successfully implanted valved stents (diameter: 24 mm in 7 sheep, 26 mm in 5 sheep) in good position in 8 sheep, in the main pulmonary artery (PA) in 2 sheep, and in the right ventricular outlet tract (RVOT) in 2 sheep. We sacrificed 8 sheep (6 sheep in good position, 1 sheep in the main PA, and 1 sheep in the RVOT) after >6 months. Five of the 6 sheep implanted in good position showed well-preserved valve morphology at the time of sacrifice. Histologic findings after routine sacrifice showed well-maintained collagen wave structure and no visible calcification in all explanted valve leaflets. Transcatheter implantation of a nitinol-wire-based, self-expandable valved stent in the pulmonic valve was feasible, and stents implanted in good position showed well-preserved valve leaflets with functional competence in the mid-term results. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Endoscopic management of complications of self-expandable metal stents for treatment of malignant esophageal stenosis and tracheoesophageal fistulas.

    PubMed

    Bor, Renáta; Fábián, Anna; Bálint, Anita; Farkas, Klaudia; Szűcs, Mónika; Milassin, Ágnes; Czakó, László; Rutka, Mariann; Molnár, Tamás; Szepes, Zoltán

    2017-08-01

    Self-expandable metal stent (SEMS) implantation may rapidly improve the symptoms of malignant esophageal stenosis and tracheoesophageal fistulas (TEF). However, dysphagia often returns subsequently and repeated endoscopic intervention may be necessary. The aims of the study were to identify the risk factors of complications, and the frequency and efficacy of repeated endoscopic interventions; and to provide technical recommendations on appropriate stent selection. We analyzed retrospectively the clinical data of 212 patients with locally advanced esophageal cancer who underwent SEMS implantation. A total of 238 SEMS implantations were performed with 99.06% technical success and 1.26% procedure-related deaths in the enrolled 212 cases. Complications occurred in 84 patients (39.62%) and in 55 cases (25.94%) repeated endoscopic procedures were required. Early reintervention 24-48 h after the stent implantations was necessary due to stent migration (12 cases), arrhythmia (2 cases), intolerable retrosternal pain (1 case) and dyspnea (1 case). An average of 1.98 repeated gastroscopies (range 1-6; median 2), 13.58 weeks (range 1.5-48; median 11) after the stent implantation were performed during the follow-up period: 37 stent repositions, 23 restent implantations, 15 endoscopic esophageal dilations and 7 stent removals. In 48 cases (87.3%) oral feeding of patients was made possible by endoscopic interventions. In a quarter of SEMS implantations, complications occur that can be successfully managed by endoscopic interventions. Our experiences have shown that individualized stent choice may substantially reduce the complications rate and make repeated endoscopic interventions easier.

  11. Esophagojejunal Anastomosis Fistula, Distal Esophageal Stenosis, and Metalic Stent Migration after Total Gastrectomy

    PubMed Central

    Al Hajjar, Nadim; Popa, Calin; Al-Momani, Tareg; Margarit, Simona; Graur, Florin; Tantau, Marcel

    2015-01-01

    Esophagojejunal anastomosis fistula is the main complication after a total gastrectomy. To avoid a complex procedure on friable inflamed perianastomotic tissues, a coated self-expandable stent is mounted at the site of the anastomotic leak. A complication of stenting procedure is that it might lead to distal esophageal stenosis. However, another frequently encountered complication of stenting is stent migration, which is treated nonsurgically. When the migrated stent creates life threatening complications, surgical removal is indicated. We present a case of a 67-year-old male patient who was treated at our facility for a gastric adenocarcinoma which developed, postoperatively, an esophagojejunostomy fistula, a distal esophageal stenosis, and a metallic coated self-expandable stent migration. To our knowledge, this is the first reported case of an esophagojejunostomy fistula combined with a distal esophageal stenosis as well as with a metallic coated self-expandable stent migration. PMID:25945277

  12. A new approach to improve the local compressive properties of PPDO self-expandable stent.

    PubMed

    Zhao, Fan; Xue, Wen; Wang, Fujun; Yu, Chenglong; Xu, Haiyan; Hao, Yi; Wang, Lu

    2017-04-01

    The radial performance of bioabsorbable polymeric intravascular stents is extremely important in assessing the efficiency of these devices in expanding narrow lumen, reducing stent recoil, and recovering to their original states after suffering from pulsating pressure. However, these stents remain inferior to metallic stents. Several thermal treatment conditions (60°C, 80°C, and 100°C for 1h) were investigated to improve the characteristics of poly(p-dioxanone) (PPDO) self-expandable stents. The local compressive force, stiffness, and viscoelasticity of these stents were also evaluated. Wide-angle X-ray diffraction and different scanning calorimetry measurements were performed to evaluate the recrystalline and thermodynamic changes of molecular chains. The declining conformer entropy of PPDO monofilaments was examined via energy analysis. The untreated stents had compressive modules of 514.80±70.59mN/mm, which was much higher than those of 80°C and 100°C treated stents (332.35±66.08mN/mm and 394.31±64.71mN/mm, respectively). Nevertheless, 100°C annealing stents had less stress relaxation and prior elastic recovery rate of 82.32±3.43mN and 92.55±1.61%, respectively, showing a much better shape stability than untreated stents (139.51±16.67mN and 86.18±3.57%, respectively). These findings present important clinical implications in the stent manufacturing process and warrant further study to develop new bioabsorbable stents with outstanding clinical efficacy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Self-Expanding Metal Stents for the Treatment of Post-Surgical Esophageal Leaks: A Tertiary Referral Center Experience.

    PubMed

    Anderloni, Andrea; Genco, Chiara; Massidda, Marco; Di Leo, Milena; Fumagalli, Uberto Romario; Rosati, Riccardo; Correale, Loredana; Maselli, Roberta; Ferrara, Elisa Chiara; Jovani, Manol; Repici, Alessandro

    2018-06-05

    The study aimed to evaluate the effectiveness and safety of self-expanding metal stents (SEMS) in the management of post-surgical esophageal leaks. Retrospective data of consecutive patients with a post-surgical esophageal leak treated by means of a metal stent between January 2008 and December 2014 at the Humanitas Research Hospital (Milan, Italy) were extracted from a prospectively maintained register of SEMS used for benign indications, such as post-surgical benign esophageal strictures and/or leaks. The primary outcome of the study was to assess the rate of successful leak closure and to identify the variables associated with its achievement. As a secondary outcome, we evaluated the overall safety of SEMS placement and the efficacy and safety for different types of SEMS in this specific setting of patients. Leak resolution was documented with endoscopic and/or imaging studies. In the case of leak persistence, further attempts of esophageal stenting were carried out at the discretion of both endoscopists and surgeons. A total of 49 patients were included in the study (men 41 of 49, 83.7%, mean age 62.4 ± 11.9). One patient was excluded from analysis, because of death 1 day after stent insertion due to worsening of pre-existing mediastinitis. A total number of 82 stents were placed (mean number of stents per patient: 1.7) in 49 patients: 35 patients (71.4%) received a partially covered SEMS (PCSEMS) as the first stent positioned, while the remaining 14 (28.6%) received a fully covered SEMS (FCSEMS); but 1 patient (2%) died following stent insertion; therefore, data regarding therapeutic success were available for 48 patients. Stents were left in place for a mean period of 21.9 ± 15.2 days. Leak closure after the first stent placement was achieved in 22 of 48 (45.8%) patients. Of the 26 patients with failure of index stent placement, 18 patients underwent further stenting attempts (69.2%), and secondary closure of leak was achieved in 7 (38.9%) of these 18

  14. Ultrathin endoscope-assisted self-expandable metallic stent placement following initial unsuccessful attempt in malignant upper gastrointestinal obstruction.

    PubMed

    Park, Se Woo; Lee, Hyuk; Park, Jun Chul; Shin, Sung Kwan; Lee, Sang Kil; Lee, Yong Chan

    2014-03-01

    Conventional endoscopy for self-expandable metallic stent (SEMS) placement may be technically limited in long and tortuous strictures. Therefore, we analyzed the feasibility, safety and usefulness of ultrathin endoscopy (UTE)-guided SEMS placement. This study involved 24 patients with upper gastrointestinal obstruction and unsuccessful initial attempts to place SEMS using conventional endoscopy. After completely passing a UTE across the stricture, the UTE was withdrawn, leaving a guidewire placed via the working channel. Through-the-scope SEMS placement was done using a conventional endoscope inserted along the guidewire. The primary endpoints were assessed by technical/clinical success and stent patency duration. Stents were successfully placed at target locations in all but one case with a long tortuous stricture, with 95.8% (23/24) technical success. One week after stent placement, mean gastricoutlet obstruction score improved significantly from baseline (1.74 ± 0.62 and 0.33 ± 0.48, respectively; P < 0.001). Stent migration, restenosis, and fracture occurred in four (17.4%), six (26.1%), and one (4.3%) of 23 stents, respectively. Median stent patency duration was 79 days. Mean stent patency was significantly longer in patients who received palliative chemotherapy than in those who did not (122.9 ± 11.0 and 38.3 ± 4.6, respectively; P < 0.001). UTE guidance SEMS delivery can be a feasible and safe rescue treatment method for malignant upper gastrointestinal obstruction in cases of failed attempts to place SEMS using conventional endoscopy. Our result warrants a further study to define the efficacy of this method in difficult SEMS placement cases. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  15. A US Multicenter Study of Safety and Efficacy of Fully Covered Self-Expandable Metallic Stents in Benign Extrahepatic Biliary Strictures.

    PubMed

    Saxena, Payal; Diehl, David L; Kumbhari, Vivek; Shieh, Frederick; Buscaglia, Jonathan M; Sze, Wilson; Kapoor, Sumit; Komanduri, Srinadh; Nasr, John; Shin, Eun Ji; Singh, Vikesh; Lennon, Anne Marie; Kalloo, Anthony N; Khashab, Mouen A

    2015-11-01

    Endoscopic therapy is considered first line for management of benign biliary strictures (BBSs). Placement of plastic stents has been effective but limited by their short-term patency and need for repeated procedures. Fully covered self-expandable metallic stents (FCSEMSs) offer longer-lasting biliary drainage without the need for frequent exchanges. The aim of this study was to assess the efficacy and safety of FCSEMS in patients with BBS. A retrospective review of all patients who underwent ERCP and FCSEMS placement at five tertiary referral US hospitals was performed. Stricture resolution and adverse events related to ERCP and/or stenting were recorded. A total of 123 patients underwent FCSEMS placement for BBS and 112 underwent a subsequent follow-up ERCP. The mean age was 62 years (±15.6), and 57% were males. Stricture resolution occurred in 81% of patients after a mean of 1.2 stenting procedures (mean stent dwell time 24.4 ± 2.3 weeks), with a mean follow-up of 18.5 months. Stricture recurrence occurred in 5 patients, and 3 patients required surgery for treatment of refractory strictures. Stent migration (9.7%) was the most common complication, followed by stent occlusion (4.9%), cholangitis (4.1%), and pancreatitis (3.3%). There was one case of stent fracture during removal, and one stent could not be removed. There was one death due to cholangitis. Majority of BBS can be successfully managed with 1-2 consecutive FCSEMS with stent dwell time of 6 months.

  16. A new self-expandable aortic valved stent deployed above native leaflets for aortic insufficiency: an in vitro study.

    PubMed

    Huang, H; Zhou, Y; Shao, J; Cai, J; Mei, Y; Wang, Y

    2012-12-01

    The aim of this paper was to develop a new self-expandable aortic valved stent following the shape of the sinus of Valsalva, which can be deployed above native leaflets for aortic regurgitation, and study it's effect on coronary artery flow when orthotopic implantation in and above native leaflets. New self-expandable aortic valved stent consist of nitinol stent and bovine pericardium, and was designed following the shape of the sinus of Valsalva, the bovine pericardium was tailed as native leaflet. Thirty-six swine hearts were divided into three equal groups of twelve. In Group A (N.=12), the new self-expandable aortic valved stents deployed in native leaflets. In Group B (N.=12), the new self-expandable aortic valved stents deployed above native leaflets. In Group C (N.=12), the cylinder-like valved stents deployed only in native leaflets. The measurements of each coronary flow rate and endoscopic inspections were repeated post-implantation. In Group A and C, valve implantation in native leaflets resulted in a significant decrease in both left and right coronary flows. In Group B, no significant change in either right or left coronary flow was found after new self-expandable aortic valved stent placement. Endoscopic inspections showed that in group A and C the native leaflets sandwiched between valved stent and aortic wall, whereas, in group B the native leaflets were under the artificial leaflets. Two kinds of stents deployed in native leaflets affect left and right coronary flows significantly. No significant effect was found when the new self-expandable aortic valved stent deployed above native leaflets. This new self-expandable aortic valved stent can be deployed above the native leaflets, which avoids the obstruction of native leaflets on coronary flow.

  17. Self-expandable metallic stent as a bridge to elective surgery versus emergency surgery for acute malignant colorectal obstruction.

    PubMed

    Li, Zhi-Xiong; Wu, Xiao-Hua; Wu, Hai-yan; Chang, Wen-Ju; Chang, Xiu-juan; Yi, Tuo; Shi, Qiang; Chen, Jing-Wen; Feng, Qing-Yang; Zhu, De-Xiang; Wei, Ye; Zhong, Yun-Shi; Xu, Jian-Min

    2016-03-01

    The efficacy and safety of self-expandable metallic stents (SEMSs) as a bridge for patients with acute malignant colorectal obstructions (AMCOs) are still controversial. We conducted this study to evaluate the outcomes of patients with AMCOs treated by different strategies. From January 2010 to March 2014, a total of 171 patients with AMCOs from Zhongshan Hospital were retrospectively enrolled in this study. One hundred twenty patients successfully received stent placement followed by one-stage laparoscopic or open resection in the stent group, and 51 patients received emergency operations in the emergency group. The operation duration and postoperative hospital stay were significantly shorter in the stent group (114.51 ± 28.65 vs. 160.39 ± 58.94 min, P < 0.001; 8.00 ± 3.97 vs. 12.59 ± 9.07 days, P = 0.001). The stent group also had significantly reduced intraoperative blood loss and the incidence of postoperative complications compared with the emergency group (61.00 ± 43.70 vs. 121.18 ± 85.90 ml, P < 0.001; 16.7 vs. 37.3%, P = 0.003). Kaplan-Meier survival curves showed that the median survival time in the stent group was significantly longer than that in the emergency group (53 vs. 41 months, P = 0.034). In subgroup analysis of stent group, the stent laparoscopy group had significantly decreased postoperative complications (P = 0.025), and similar long-term survival (P = 0.81). Stent placement as a bridge to surgery is a safe and feasible procedure and provides significant advantages in terms of short-term outcomes and favorable prognoses for patients with AMCOs. Laparoscopic surgery could be considered as an optimal treatment after stent placement.

  18. Clinical feasibility of a new through-the-scope fully covered esophageal self-expandable metallic stent: an in vivo animal study.

    PubMed

    Cheon, Young Koog; Lee, Tae Yoon; Sung, In Kyung; Shim, Chan Sup

    2014-01-01

    Most delivery devices used for esophageal stents for obstructing esophageal cancer have a diameter of 5-8 mm, a size that is too large to pass through the endoscopic working channel. The conventional esophageal stent requires multiple endoscopic procedures for implantation. The purpose of the present study was to evaluate the clinical feasibility of a newly developed fully covered, self-expanding, through-the-scope (TTS) esophageal stent in a porcine model. Eight mini pigs were used. Each animal underwent placement of a fully covered TTS stent (Hanarostent® Esophagus TTS) and the upper part of the stent was fixed by suturing with nylon. Fluoroscopy was carried out every week to assess migration of the stent. Follow-up endoscopy was done every month for 3 months to evaluate the status of the membrane, stent mesh, grade of tissue hyperplasia, and mucosal changes at both ends of the stent. All stents were successfully and easily deployed, and were placed without any distortion in the stent or without rupture of the membrane. In two cases, stent migration was observed after 8 weeks. No case of membrane disruption, stent mesh disruption or tissue hyperplasia at either end of the stent was found at the completion of the study. Our findings indicate that the new fully covered self-expanding TTS esophageal stent is easy and simple to implant, and no significant distortion of mesh or disruption of membrane was observed. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  19. Comparison between gastrostomy feeding and self-expandable metal stent insertion for patients with esophageal cancer and dysphagia.

    PubMed

    Min, Yang Won; Jang, Eun Young; Jung, Ji Hey; Lee, Hyuk; Min, Byung-Hoon; Lee, Jun Haeng; Rhee, Poong-Lyul; Kim, Jae J

    2017-01-01

    Self-expandable metal stent (SEMS) insertion and percutaneous gastrostomy (PG) feeding are commonly used for patients with esophageal cancer and dysphagia. This study aimed to compare outcomes between SEMS insertion and PG feeding for them. We retrospectively analyzed 308 patients with esophageal cancer who underwent fully covered SEMS insertion (stent group) or PG (gastrostomy group) for dysphagia due to tumor. Patients with other causes of dysphagia, such as radiation-induced or postoperative stricture, were excluded from the study. Clinical outcomes were compared between the two groups, including overall survival and need for additional intervention and postprocedural nutritional status. At baseline, the stent group (n = 169) had more stage IV patients, less cervical cancers, and received radiotherapy and esophagectomy less often than the gastrostomy group (n = 64). The Kaplan-Meier curves showed higher overall survival in the gastrostomy group than in the stent group. Multivariate analysis revealed that PG was associated with better survival compared with SEMS insertion (hazard ratio 0.541, 95% confidence interval 0.346-0.848, p = 0.007). In addition, the gastrostomy group needed additional intervention less often (3.1% vs. 21.9%, p < 0.001) and experienced less decrease in serum albumin levels (-0.15 ± 0.56 g/dL vs. -0.39 ± 0.58 g/dL, p = 0.011) than the stent group after procedure. Our data suggested that, compared with SEMS insertion, PG is associated with better overall survival in patients with esophageal cancer and dysphagia. Stabilized nutritional status by PG may play a role in improving patient survival.

  20. Success and complications of an intra-ductal fully covered self-expanding metal stent (ID-FCSEMS) to treat anastomotic biliary strictures (AS) after orthotopic liver transplantation (OLT).

    PubMed

    Aepli, Patrick; St John, Andrew; Gupta, Saurabh; Hourigan, Luke F; Vaughan, Rhys; Efthymiou, Marios; Kaffes, Arthur

    2017-04-01

    Anastomotic biliary strictures (AS) after orthotopic liver transplantation (OLT) belong to the most common biliary complications and cause the biggest morbidity burden after OLT. Metal stents for benign biliary strictures are gaining acceptance with many published series. Traditional metal stent designs seem to have poor durability in AS after OLT. Novel intra-ductal stents are showing promise in these strictures. As a result, we designed a special stent with an antimigration waist and a short stent length with a long removal string that rests in the duodenum for easy removal. This is a retrospective multi-centre Australian study of AS after OLT treated with a novel intra-ductal fully covered self-expanding metal stent. From August 2008 to October 2014, records from three liver transplant centres were reviewed. Totally 36 ID-FCSEMS were inserted in 31 cases to treat an AS after OLT. The mean age of the patients was 56 years, and 61 % were male. The mean time of AS presentation after OLT was 20.3 months. Eight out of our 31 patients were previously treated using multiple plastic stenting over time without any success. Treatment with the ID-FCSEMS was performed with an average treatment time of 3.8 months. Stricture resolution was achieved in 100 %. All attempted stents removals were successful without any difficulty. Complications were reported in 6.5 %. It was pleasing that only one case of stent migration (2.8 %) was seen. Follow-up showed seven cases of AS recurrence (24.1 %), and all were treated successfully with repeat ERCP and stenting (some metal, some plastic). This novel ID-FCSEMS has a high clinical success and low complication rate, and in particular, there was only one case of stent migration. As a result, this stent type is preferred to traditional metal stents for treating AS after OLT.

  1. Self-expandable metal stent placement in a child for treatment of achalasia after failed Heller myotomy.

    PubMed

    Gugig, Roberto; Muñoz Jurado, Guillermo; Huang, Clifton; Oleas, Roberto; Robles-Medranda, Carlos

    2018-01-01

    Background and study aims  Childhood achalasia treatment remains inconclusive. What is next after myotomy failure? Repeated pneumatic-dilation put patients at greater risk of perforation with possible symptom recurrence. We report on a 12-year-old patient with a 1-year history of achalasia whom underwent Heller myotomy with fundoplication and recurred with symptoms 1 week after surgery. Pneumatic dilatation was considered but not done because of the risk of esophageal perforation. The decision was made to place a fully covered self-expanding metallic stent (FC-SEMS) for 3 months, which resolved the stenosis as confirmed by esophagram. The patient has remained asymptomatic since the procedure was performed 2 years ago. FC-SEMS is an alternative for treatment of refractory achalasia in children who do not respond to conventional treatment.

  2. Efficacy and complications in the use of self-expanding colonic stents: an analysis of 15 years' experience.

    PubMed

    Samper Wamba, J D; Fernández Martínez, A; González Pastrana, L; López González, L; Balboa Arregui, Ó

    2015-01-01

    To analyze the efficacy and safety of the procedure for placing self-expanding stents in the colon. To evaluate the factors associated with complications. To analyze the dose of radiation delivered in the procedure. This was a retrospective descriptive study of 478 procedures done at a single center to place self-expanding metallic stents in the colon. A total of 423 nitinol stents and 79 stainless steel stents were placed. We included all colonic obstructions, of which 446 had malignant causes and 8 had benign causes. We excluded patients with intestinal perforation, severe colonic bleeding, short life expectancy, or lesions located less than 5 cm from the anus. We collected the dosimetric data and analyzed the technical success, clinical success, and complications during follow-up. The procedure was a technical success in 92.26% of cases (n=441) and a clinical success in 78.45% (n=375); complications occurred during follow-up in 18.5% of cases. Complications occurred more frequently with the stainless steel stents than with the nitinol stents (OR: 3.2; 95% CI: 1.8-5.7). The mean value of the dose area product was 35 Gy*cm(2). When instead of being done by the interventional radiologist working together with an endoscopist the procedure was done exclusively by the interventional radiologist, the time under fluoroscopy (p=0.001), dose area product (p=0.029), and kinetic energy released per unit mass (p=0.001) were greater. The procedure for placing self-expanding colonic stents is efficacious and safe with an acceptable rate of complications. The doses of radiation delivered were low, and the radiation doses and time under fluoroscopy were lower when the procedure was done together with an endoscopist. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  3. Medium-term follow-up after deployment of ultraflex expandable metallic stents to manage endobronchial pathology.

    PubMed

    Madden, Brendan P; Park, John E S; Sheth, Abhijat

    2004-12-01

    Between March 1997 and March 2004 we deployed 80 Ultraflex metallic expandable stents (Boston Scientific, Waterson, MA) in 69 patients under direct vision using rigid bronchoscopy. We report our medium- to long-term experience in patients for whom these stents were deployed. To date 15 patients have been followed for more than 1 year (median 41 months, range 12 to 83 months) after stent deployment. Indications for stenting in these patients were neoplasia (5), stricture (5), airway malacia (1), iatrogenic tracheal tear (1), and compression from an aortic aneurysm (1), a right interrupted aortic arch (1), and a right brachiocephalic artery aneurysm with tracheomalacia (1). Ten tracheal stents (9 covered, 1 uncovered) and 10 bronchial stents (8 uncovered, 2 covered) were inserted, and 5 patients received two stents. Five of these patients experienced no long-term problems. Complications included troublesome halitosis (5), which was difficult to treat despite various antibiotic regimes; granulation tissue formation above and below the stent that was successfully treated with low-power Nd:YAG laser therapy (7); and metal fatigue (1). We did not encounter stent migration. We conclude that Ultraflex expandable metallic stents have an important role in the management of selected patients with diverse endobronchial pathologies and are well tolerated in the long-term. Although associated granulation tissue can be successfully treated with Nd:YAG laser, halitosis can be a difficult problem to address.

  4. Efficacy of laser photoablative therapy and expandable metal stents for esophageal carcinoma

    NASA Astrophysics Data System (ADS)

    Balachandar, Gowra; Trowers, Eugene A.

    2000-05-01

    Malignant dysphagia is a serious condition in which 70% of patients die within one year, regardless of the treatment received. It provokes a rapid deterioration of a patient's physical condition and a significant worsening of quality of life. The surgical treatment of dysphagia is frequently complicated with technical difficulties, and often the tumors cannot be excised because of extensive invasion into adjacent structures. Furthermore, many patients are considered inoperable due to advanced age, associated diseases and malnutrition. Laser photoablative therapy coupled with expandable metal stents restores luminal patency in more than 80% of patients allowing them to eat liquids and soft foods. The efficacy of laser photoablative therapy and expandable metal stents for the palliation esophageal carcinoma will be critically reviewed.

  5. The use of retrievable fully covered self-expanding metal stent in refractory postoperative restenosis of benign esophageal stricture in children.

    PubMed

    Zhang, Jie; Ren, Lixin; Huo, Jirong; Zhu, Zhiyuan; Liu, Deliang

    2013-11-01

    This study analyzes the efficacy and safety of a retrievable, fully covered self-expanding metal stent (cSEMS) in the treatment of refractory benign esophageal restenosis in children. This is a retrospective analysis of the application of a newly designed cSEMS in treating refractory benign postoperative restenosis in five children with ages ranging from 16 months to 8 years. Efficacy and safety were evaluated during the follow-up period. cSEMS with or without an antireflux valve at the distal end were successfully placed and removed in five children. These five patients were followed up for 4-12 months after stent removal. Among the five patients, ulcerative stricture was observed in two patients because of reflux esophagitis, while three patients showed no signs of stricture recurrence. Stent migration was observed in three patients, two of which required the stent to be reset. The narrow esophagus was successfully expended to a diameter of 12-13 mm. Besides the observation of mild granulation tissue growth in one case, no severe complications were observed during surgery and after stent placement. Our study suggests that a retrievable, fully covered SEMS is safe and partially effective for treating refractory benign postoperative esophageal restenosis in children during short-term observation. © 2013.

  6. Primary Self-Expandable Nitinol Stent Placement in Focal Lesions of Infrarenal Abdominal Aorta: Long Term Results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lastovickova, Jarmila, E-mail: jala@medicon.cz; Peregrin, Jan H.

    Purpose. To evaluate the technical and clinical success, safety and long term results of percutaneous transluminal angioplasty/self-expandable nitinol stent placement of infrarenal abdominal aorta focal lesions. Materials and Methods. Eighteen patients underwent PTA of focal atherosclerotic occlusive disease of distal abdominal aorta. Two symptomatic occlusions and 16 stenoses in 10 male and 8 female patients (mean age 68.2 years) were treated with primary self-expandable nitinol stent placement. Results. Primary self-expandable nitinol stent placement was technically successful in all 18 procedures; clinical success was achieved in 100% of patients. No complications associated with the procedure occurred. During the 49.4 months ofmore » mean follow up (range 3-96, 4 months) all treated aortic segments remained patent. Conclusions. Endovascular treatment (primary self-expandable nitinol stent placement) of focal atherosclerotic lesions of distal abdominal aorta is a safe method with excellent primary technical and clinical success rates and favourable Long term results.« less

  7. Coated and uncoated self-expanding metal stents for malignant stenosis in the upper GI tract: preliminary clinical experiences with Wallstents.

    PubMed

    Ell, C; Hochberger, J; May, A; Fleig, W E; Hahn, E G

    1994-09-01

    The clinical feasibility of self-expanding metal stents with respect to the technical success, complications, and reintervention rate should be tested. Five coated and 26 uncoated prototype Wallstents, especially designed for stenosis of the upper GI tract, were implanted in 23 patients. All patients with dysphagia suffered from inoperable tumor stenosis of the esophagus or the cardia. Stent implantation was performed under slight i.v. sedoanalgesia. Technical success was achieved in all 31 implanted stents. Forty-eight hr after implantation, dysphagia was improved in 21/23 patients. Acute problems observed within 1 wk were stent migration (1 patient, uncoated stent), oblique position of the stent (3 patients), epigastric or retrosternal pain (9 patients), insufficient stent expansion (4 patients), and pouch formation at the upper rim of the stent (4 patients). An uncomplicated follow-up (median 66 days, range 10-139 days) was seen in 12 patients (52%). Major problems in the follow-up period were stent migration in three patients (three coated stents, two stent migrations in one patient) and stent obstruction by tumor ingrowth/overgrowth and/or food impaction in eight patients (35%). Most of these problems could be successfully resolved by implantation of a second stent or electrocoagulation of overgrowing tumor tissue. By the 1st of March, 1994, three patients were still alive with a follow-up period of 530 days (median range, 336-880 days); 20 patients were decreased with a follow-up period of 70 days (median range, 3-374 days). Implantation of esophageal Wallstents is safe and has a low risk of acute complications and mortality for the patient. Early complications such as perforation and bleeding did not occur. Tumor ingrowth/overgrowth are the major reasons for the high reintervention rate in the follow-up period. Coated stents can resolve this problem, provided that stent migration can be avoided by improvement of the coating technology.

  8. In vivo evaluation of a new bioabsorbable self-expanding biliary stent.

    PubMed

    Ginsberg, Gregory; Cope, Constantin; Shah, Janak; Martin, Tanisha; Carty, Anthony; Habecker, Perry; Kaufmann, Carol; Clerc, Claude; Nuutinen, Juha-Pekka; Törmälä, Pertti

    2003-11-01

    Bioabsorbable stents may offer advantages for the treatment of benign and malignant biliary strictures, including large stent diameter, decreased biofilm accumulation and proliferative changes, elimination of the need for stent removal and imaging artifacts, and prospects for drug impregnation. However, suboptimal expansion has hampered prior iterations. A new bioabsorbable biliary stent (BioStent) was evaluated in a porcine model. BioStents were placed in 8 animals for long-term follow-up. The following were evaluated: accuracy and ease of delivery and deployment, radial expansion, and radiologic visualization. Stent function and biotolerance were assessed by cholangiography, serum bilirubin, and necropsy for histopathology performed in pairs at 2, 4, 6, and 12 months. Stents were delivered without sphincterotomy and were deployed easily, accurately, and with good immediate stent expansion and radiographic visualization. On follow-up, all stents were fully expanded and serum bilirubin levels remained within the normal range. Although there was no clinical evidence of biliary obstruction, filling defects were common at cholangiography. On histopathologic evaluation, there was neither bile duct integration or proliferative change. The BioStent bioabsorbable biliary stent, modified with axial runners, can be effectively deployed endoscopically, is self-expanding, is visualized radiographically, and remains patent up to 6 months. There was no bile duct integration or proliferative change, which are potential advantages. Stent occlusion and migration remain concerns.

  9. Hepatocellular Carcinoma Complicated by Gastroduodenal Obstruction: Palliative Treatment with Metallic Stent Placement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, Ye Jin; Kim, Jin Hyoung, E-mail: m1fenew@daum.net; Song, Ho-Young

    Purpose: To evaluate the clinical effectiveness of self-expandable metallic stents in seven patients with malignant gastroduodenal obstruction caused by inoperable hepatocellular carcinoma (HCC). Methods: Seven patients with gastroduodenal obstruction caused by advanced HCC underwent metallic stent placement from 2003 to 2010. These patients had total dysphagia (n = 5) or were able to eat only liquids (n = 2) before stent placement. Patients had Eastern Cooperative Oncology Group performance scores of 2 or 3, and Child-Pugh classification B or C. Results: Stent placement was technically successful in all seven patients (100%) and clinically successful in six (86%). Five patients couldmore » eat a soft diet, and one patient tolerated regular diet after stent placement. Stent-related obstructive jaundice occurred in one patient. One patient had hematemesis 11 days after stent placement. Overall mean survival was 51 days (range, 10-119 days). Stent patency was preserved in six patients with clinical success until death. Conclusion: Placement of a covered self-expandable metallic stent may offer good palliation in patients with gastroduodenal obstruction due to advanced HCC.« less

  10. [Self-expanding antireflux stents for malignant esophageal stenosis - a report of three cases].

    PubMed

    Kusano-Kitazume, Akiko; Ami, Katsunori; Nagahama, Takeshi; Kondo, Mayumi; Okamoto, Eiko; Tamura, Atsushi; Takagi, Kentaro; Hayasaka, Junnosuke; Watanabe, Ayako; Kawai, Yosuke; Fujiya, Keiichi; Amagasa, Hidetoshi; Ganno, Hideaki; Imai, Kenichiro; Fukuda, Akira; Ando, Masayuki; Arai, Kuniyoshi; Shibayama, Takao

    2014-11-01

    Use of a standard open stent or self-expanding metal stent for patients with malignant dysphagia is associated with a risk of gastroesophageal reflux especially when placed across the esophagogastric junction. We report 3 cases of malignant esophageal stenosis treated with a long cover-type Niti-STM stent with an antireflux mechanism. Case 1: A 87-year-old man presented with dysphagia due to esophageal cancer at the middle thoracic esophagus. Two months after surgery using a standard open stent, the dysphagia relapsed because of tissue overgrowth. Case 2: A 73-year-old woman presented with lung cancer and severe dysphagia due to enlarged mediastinal lymph nodes. Case 3: A 66-year-old man presented with dysphagia due to esophageal cancer at the lower thoracic esophagus. All 3 patients received an antireflux stent across the esophagogastric junction. In cases 1 and 2, dysphagia was relieved immediately without complications. In case 3, the patient experienced severe reflux and chest pain associated with stent placement and could not ingest any solid food. We conclude that the antireflux stent may be useful for palliation in patients with severe malignant esophageal obstruction; however, patients should be informed about the risk of failure to prevent reflux.

  11. A fully covered self-expandable metal stent with antimigration features for benign biliary strictures: a prospective, multicenter cohort study.

    PubMed

    Walter, Daisy; Laleman, Wim; Jansen, Jeroen M; van Milligen de Wit, A W M; Weusten, Bas L; van Boeckel, Petra G; Hirdes, Meike M; Vleggaar, Frank P; Siersema, Peter D

    2015-05-01

    Self-expandable metal stents (SEMSs) are increasingly used for the treatment of benign biliary strictures (BBSs). A new fully covered SEMS (FCSEMS) with flared ends and high conformability was designed to prevent migration of the stent. To evaluate the efficacy of a novel FCSEMS with antimigration features. Prospective cohort study. Five hospitals in the Netherlands and Belgium. Consecutive patients with BBS. FCSEMS placement for 3 months. Initial and long term clinical success, stent migration rate and safety. Thirty-eight patients (24 men; mean age, 53 ± 16 years) were included. Stent placement was technically successful in 37 patients (97%). Two patients died of an unrelated cause before stent removal, and no data on these patients were available on stricture resolution. Initial clinical success was achieved in 28 of 35 patients (80%). During follow-up after stent removal, a symptomatic recurrent stricture developed in 6 of 28 patients (21%). Overall, the long-term clinical success rate was 63% (22 of 35 patients). Stent migration occurred in 11 of 35 patients (31%), including 5 symptomatic (14%) and 6 asymptomatic (17%) migrations. In total, 11 serious adverse events occurred in 10 patients (29%), with cholangitis (n = 5) being most common. Nonrandomized study design. Good initial clinical success was achieved after placement of this novel FCSEMS, but stricture recurrence was in the upper range compared with other FCSEMSs. The antimigration design could not prevent migration in a significant number of patients with a persisting stricture. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  12. Role of metallic stents in benign esophageal stricture

    NASA Astrophysics Data System (ADS)

    Shim, Chan Sup

    2012-10-01

    Simple esophageal strictures, which are focal, straight, and large in diameter, usually require 1 - 3 dilation sessions to relieve symptoms. However, complex strictures, which are long, tortuous, or associated with a severely compromised luminal diameter, are usually more difficult to treat with conventional bougie or balloon dilation techniques, and often have high recurrence rates. Although the permanent placement of self-expandable metal stents (SEMS) has been used to manage refractory benign esophageal strictures, this procedure is associated with additional problems, such as stricture from tissue hyperplasia, stent migration, and fistula formation. Thus, several new types of stents have been developed, including temporary SEMS, self-expandable plastic stents (SEPS), and biodegradable stents. The use of these new products has produced varied results. Temporary SEMS that have been used to relieve benign esophageal conditions have caused granulation tissue at both ends of the stent because of contact between the mucosa and the exposed metal components of the stent, thus hindering stent removal. We examined the tissue response to two new types of SEMS, a flange-type and a straighttype, each coated with a silicone membrane on the outside of the metal mesh. These two SEMS were evaluated individually and compared with a conventional control stent in animal experiments. Although the newly designed stents resulted in reduced tissue hyperplasia, and were thus more easily separated from the esophageal tissue, some degree of tissue hyperplasia did occur. We suggest that newly designed DES (drug-eluting stents) may provide an alternative tool to manage refractory benign esophageal stricture.

  13. Self-Expandable Nitinol Stent Placement in Homocysteinemic Porcine Aorta

    PubMed Central

    França, Luís Henrique Gil; Pereira, Adamastor Humberto; Perini, Sílvio César

    2008-01-01

    PURPOSE To compare aortic intimal thickening of normal and hyperhomocysteinemic pigs (induced with a methionine-rich diet) following placement of a self-expanding nitinol stent. METHODS Eighteen Macau pigs were used. They were older than eight weeks in age and had an average weight of 30 kg. Pigs were randomly divided into two groups. The first, Group C (control), was fed a regular diet, and the second group, Group M, was fed a methionine-rich diet for 30 days to induce hyperhomocysteinemia. The self-expandable nitinol stents were 25mm in length and 8 mm in diameter after expansion. Blood samples were collected to measure total cholesterol, triglycerides, HDL and homocysteine concentrations. All animals were subjected to angiography. Thirty days after the procedure, the animals were sacrificed, and the abdominal aorta was removed for histological and digital morphometry analysis. RESULTS Under microscopic evaluation, the intima was significantly thicker in Group C than in Group M. When groups were compared by digital morphometric analysis, intimal thickening of the vessel wall was higher in Group C than in Group M. There was no significant change in total cholesterol, triglycerides or HDL concentrations in either group. In group C the levels of plasma homocysteine ranged from 14,40 to 16,73μmol/l; in Group M, plasma homocysteine levels ranged from 17.47 to 59.80 μmol/l after 30 days of a methionine-rich diet. CONCLUSION Compared to normal pigs, less intimal hyperplasia was observed in the abdominal aortas of hyperhomocysteinemic pigs thirty days after the insertion of a self-expandable nitinol stent. PMID:18438578

  14. Comparison between gastrostomy feeding and self-expandable metal stent insertion for patients with esophageal cancer and dysphagia

    PubMed Central

    Jung, Ji Hey; Lee, Hyuk; Min, Byung-Hoon; Lee, Jun Haeng; Rhee, Poong-Lyul; Kim, Jae J.

    2017-01-01

    Background Self-expandable metal stent (SEMS) insertion and percutaneous gastrostomy (PG) feeding are commonly used for patients with esophageal cancer and dysphagia. This study aimed to compare outcomes between SEMS insertion and PG feeding for them. Methods We retrospectively analyzed 308 patients with esophageal cancer who underwent fully covered SEMS insertion (stent group) or PG (gastrostomy group) for dysphagia due to tumor. Patients with other causes of dysphagia, such as radiation-induced or postoperative stricture, were excluded from the study. Clinical outcomes were compared between the two groups, including overall survival and need for additional intervention and postprocedural nutritional status. Results At baseline, the stent group (n = 169) had more stage IV patients, less cervical cancers, and received radiotherapy and esophagectomy less often than the gastrostomy group (n = 64). The Kaplan-Meier curves showed higher overall survival in the gastrostomy group than in the stent group. Multivariate analysis revealed that PG was associated with better survival compared with SEMS insertion (hazard ratio 0.541, 95% confidence interval 0.346–0.848, p = 0.007). In addition, the gastrostomy group needed additional intervention less often (3.1% vs. 21.9%, p < 0.001) and experienced less decrease in serum albumin levels (-0.15 ± 0.56 g/dL vs. -0.39 ± 0.58 g/dL, p = 0.011) than the stent group after procedure. Conclusions Our data suggested that, compared with SEMS insertion, PG is associated with better overall survival in patients with esophageal cancer and dysphagia. Stabilized nutritional status by PG may play a role in improving patient survival. PMID:28632744

  15. Treatment of esophageal anastomotic leakage with self-expanding metal stents: analysis of risk factors for treatment failure

    PubMed Central

    Persson, Saga; Rouvelas, Ioannis; Kumagai, Koshi; Song, Huan; Lindblad, Mats; Lundell, Lars; Nilsson, Magnus; Tsai, Jon A.

    2016-01-01

    Background and study aim: The endoscopic placement of self-expandable metallic esophageal stents (SEMS) has become the preferred primary treatment for esophageal anastomotic leakage in many institutions. The aim of this study was to investigate possible risk factors for failure of SEMS-based therapy in patients with esophageal anastomotic leakage. Patients and methods: Beginning in 2003, all patients with an esophageal leak were initially approached and assessed for temporary closure with a SEMS. Until 2014, all patients at the Karolinska University Hospital with a leak from an esophagogastric or esophagojejunal anastomosis were identified. Data regarding the characteristics of the patients and leaks and the treatment outcomes were compiled. Failure of the SEMS treatment strategy was defined as death due to the leak or a major change in management strategy. The risk factors for treatment failure were analyzed with simple and multivariable logistic regression statistics. Results: A total of 447 patients with an esophagogastric or esophagojejunal anastomosis were identified. Of these patients, 80 (18 %) had an anastomotic leak, of whom 46 (58 %) received a stent as first-line treatment. In 29 of these 46 patients, the leak healed without any major change in treatment strategy. Continuous leakage after the application of a stent, decreased physical performance preoperatively, and concomitant esophagotracheal fistula were identified as independent risk factors for failure with multivariable logistic regression analysis. Conclusion: Stent treatment for esophageal anastomotic leakage is successful in the majority of cases. Continuous leakage after initial stent insertion, decreased physical performance preoperatively, and the development of an esophagotracheal fistula decrease the probability of successful treatment. PMID:27092321

  16. Current Status of Biliary Metal Stents

    PubMed Central

    Nam, Hyeong Seok; Kang, Dae Hwan

    2016-01-01

    Many advances have been achieved in biliary stenting over the past 30 years. Endoscopic stent placement has become the primary management therapy to relieve obstruction in patients with benign or malignant biliary tract diseases. Compared with plastic stents, a self-expandable metallic stent (SEMS) has been used for management in patients with malignant strictures because of a larger lumen and longer stent patency. Recently, SEMS has been used for various benign biliary strictures and leaks. In this article, we briefly review the characteristics of SEMS as well as complications of stent placement. We review the current guidelines for managing malignant and benign biliary obstructions. Recent developments in biliary stenting are also discussed. PMID:26911896

  17. Preoperative biliary drainage using a fully covered self-expandable metallic stent for pancreatic head cancer: A prospective feasibility study.

    PubMed

    Togawa, Osamu; Isayama, Hiroyuki; Kawakami, Hiroshi; Nakai, Yousuke; Mohri, Dai; Hamada, Tsuyoshi; Kogure, Hirofumi; Kawakubo, Kazumichi; Sakamoto, Naoya; Koike, Kazuhiko; Kita, Hiroto

    2018-01-01

    The role of endoscopic preoperative biliary drainage (PBD) for pancreatic head cancer is controversial because of the high incidence of stent occlusion before surgery. This study was performed to evaluate the feasibility and safety of PBD using a fully covered self-expandable metallic stent (FCSEMS). This multicenter prospective study involved 26 patients treated for pancreatic head cancer with distal bile duct obstruction from April 2011 to March 2013. An FCSEMS was endoscopically placed in 24 patients. Among these, 7 patients were diagnosed with unresectable cancer, and 17 underwent surgery at a median of 18 days after FCSEMS placement. The main outcome measure was preoperative and postoperative adverse events. Two adverse events (cholecystitis and insufficient resolution of jaundice) occurred between FCSEMS placement and surgery (12%). Postoperative adverse events occurred in eight patients (47%). The cumulative incidence of stent-related adverse events 4 and 8 weeks after FCSEMS placement among the 24 patients who underwent this procedure were 19%. PBD using an FCSEMS is feasible in patients with resectable pancreatic head cancer. Placement of an FCSEMS can be an alternative PBD technique when surgery without delay is impossible. A larger randomized controlled trial is warranted.

  18. Self-expanding stent for spontaneous coronary artery dissection: a rational choice.

    PubMed

    Mele, Marco; Langialonga, Tommaso; Maggi, Alessandro; Villella, Massimo; Villella, Alessandro

    2016-12-01

    : Spontaneous coronary artery dissection (SCAD) is a rare and poorly understood cause of acute coronary syndrome in relatively young patients. Nowadays, the optimal treatment of SCAD is uncertain. A conservative approach seems to be preferable, but in particular conditions, an invasive strategy is necessary. The poor rate of procedural success, the high risk of procedural complications and the uncertain long and mid-term results make the interventional treatment of SCAD a challenge. We report a case of a young male patient presenting with SCAD successfully treated with a sirolimus-eluting self-expanding coronary stent. To our knowledge, the use of self-expanding coronary stent for SCAD has never been described yet and we discuss about the rationale of a possible larger use in clinical practice.

  19. Evaluation of a fully covered self-expanding metal stent with flared ends in malignant biliary obstruction: a multicenter study.

    PubMed

    Kahaleh, Michel; Talreja, Jayant P; Loren, David E; Kowalski, Thomas E; Poneros, John M; Degaetani, Marisa; Raijman, Isaac; Sejpal, Divyesh V; Patel, Sandeep; Rosenkranz, Lauren; McNamara, Kevin N; Brijbassie, Alan; Wang, Andrew Y; Gaidhane, Monica; Sethi, Amrita; Stevens, Peter D

    2013-01-01

    Limited data are available regarding fully covered metal stents in the management of malignant distal biliary strictures. The aim of this study was to evaluate the safety of a fully covered self-expanding metal stent (FCSEMS) with flared ends, in treating malignant biliary strictures. We report our long-term retrospective analysis from 6 centers. A total of 260 patients (142 males, median age 68 y) underwent endoscopic retrograde cholangiopancreatography with placement of FCSEMS (WallFlex; Boston Scientific, Natick, MA) for the palliation of obstructive jaundice in the setting of pancreatic adenocarcinoma (169), metastatic disease (36), cholangiocarcinoma (23), ampullary cancer (19), or other (13). Patients were evaluated clinically in follow-up and biochemical tests of liver function were obtained. Data were recorded for the following variables: patient survival, duration of stent patency, the need for subsequent biliary intervention, and complications. A total of 266 FCSEMS were placed in 260 patients. There was a median survival of 100 days (range, 7 to 531 d). There was a mean follow-up of 134±118 days (range, 4 to 519 d). Biliary decompression was successful in 252 patients (97%). At the end of the study period, 121 were alive with a patent stent, 65 patients died with a patent stent, 40 patients were successfully bridged to surgery, 8 patients had their patent stent removed and had no need for further stenting, and 18 patients were lost to follow-up. Five patients who had a successfully placed FCSEMS were considered a failure due to the following reason: migration (2), cholangitis (1), stent occlusion (1), and removal for management of proximal biliary obstruction (1). Two additional patients experienced migration that did not require FCSEMS removal or replacement. Stent replacement was required in 10 patients, of whom 6 had a second FCSEMS placed. The remaining 4 were in the failure group and underwent replacement with either uncovered stents or plastic

  20. Clinical benefits and oncologic equivalence of self-expandable metallic stent insertion for right-sided malignant colonic obstruction.

    PubMed

    Ji, Woong Bae; Kwak, Jung Myun; Kang, Dong Woo; Kwak, Han Deok; Um, Jun Won; Lee, Sun-Il; Min, Byung-Wook; Sung, Nak Song; Kim, Jin; Kim, Seon Hahn

    2017-01-01

    The efficacy of stenting for right-sided malignant colonic obstruction is unknown. This study aimed to evaluate the safety, feasibility, and clinical benefits of self-expandable metallic stent insertion for right-sided malignant colonic obstruction. Clinical data from patients who underwent right hemicolectomy for right colon cancer from January 2006 to July 2014 at three Korea University hospitals were retrospectively reviewed. A total of 39 patients who developed malignant obstruction in the right-sided colon were identified, and their data were analyzed. Stent insertion was attempted in 16 patients, and initial technical success was achieved in 14 patients (87.5 %). No stent-related immediate complications were reported. Complete relief from obstruction was achieved in all 14 patients. Twenty-five patients, including two patients who failed stenting, underwent emergency surgery. In the stent group, 93 % (13/14) of patients underwent elective laparoscopic surgery, and only one surgery was converted to an open procedure. All patients in the emergency group underwent emergency surgery within 24 h of admission. In the emergency group, only 12 % (3/25) of patients underwent laparoscopic surgery, with one surgery converted to an open procedure. All patients in both groups underwent either laparoscopy-assisted or open right/extended right hemicolectomy with primary anastomoses as the first operation. The operative times, retrieved lymph nodes, and pathologic stage did not differ between the two groups. Postoperative hospital stay (9.4 ± 3.4 days in the stent group vs. 12.4 ± 5.9 in the emergency group, p = 0.089) and time to resume oral food intake (3.2 ± 2.1 days in the stent group vs. 5.7 ± 3.4 in the emergency group, p = 0.019) were shorter in the stent group. And there were no significant differences in disease-free survival and overall survival between the two groups. Stent insertion appears to be safe and feasible in patients with right

  1. Efficacy of Endoscopic Over 3-branched Partial Stent-in-Stent Drainage Using Self-expandable Metallic Stents in Patients With Unresectable Hilar Biliary Carcinoma.

    PubMed

    Uchida, Daisuke; Kato, Hironari; Muro, Shinichiro; Noma, Yasuhiro; Yamamoto, Naoki; Horiguchi, Shigeru; Harada, Ryo; Tsutsumi, Koichiro; Kawamoto, Hirofumi; Okada, Hiroyuki; Yamamoto, Kazuhide

    2015-07-01

    The treatment of biliary stricture is crucially important for continuing stable chemotherapy for unresectable biliary carcinoma; however, there is no consensus regarding the use of hilar biliary drainage. In this study, we examined the efficacy of endoscopic over 3-branched biliary drainage using self-expandable metallic stents (SEMSs) in patients with unresectable malignant hilar biliary stricture (HBS). A total of 77 patients with unresectable HBS treated with a SEMS and chemotherapy were retrospectively reviewed. There were 59 patients with cholangiocarcinoma and 18 patients with gallbladder carcinoma. The patients were divided into 2 groups (4- or 3-branched group and 2- or 1-branched group) and compared with respect to the duration of stent patency and overall survival. A comparison of the patients' baseline characteristics showed no significant differences between the 4- or 3-branched group and the 2- or 1-branched group. Neither the duration of patency nor survival time exhibited significant differences between the 2 groups, although, among the patients achieving disease control , the duration of patency period and survival time of the 4- or 3-branched group were significantly higher than those observed in the 2- or 1-branched group (P=0.0231 and 0.0466). The use of endoscopic over 3-branched biliary drainage with a SEMS may improve the duration of patency in patients with HBS.

  2. First Experience of Inserting a Metallic Mesh Stent (Uventa Stent) in Malignant Ureteral Obstruction in Iran.

    PubMed

    Ghaed, Mohammad Ali; Daniali, Maziar; Ebrahimian, Mohammad

    2018-05-03

    Malignant ureteral obstruction is usually caused by an extrinsic compression including intra-abdominal cancers. One of the treatment modalities decompressing the obstruction is applying stent to open the ureter. Metallic Stent is an effective instrument which we used for the first time in Iran in our patient who had a metastatic colon cancerwith a single kidney and we used a Novel, Double-Layered, Coated, Self-expandable Metallic Mesh Stent (Uventa Stent) to keep the ureter open. After six months of follow up with ureteroscopy, there was no obstruction any more.

  3. Anchoring of a fully covered self-expandable metal stent with a 5F double-pigtail plastic stent to prevent migration in the management of benign biliary strictures.

    PubMed

    Park, Jong Kyu; Moon, Jong Ho; Choi, Hyun Jong; Min, Seul Ki; Lee, Tae Hoon; Cheon, Gab Jin; Cheon, Young Koog; Cho, Young Deok; Park, Sang-Heum; Kim, Sun-Joo

    2011-10-01

    Fully covered self-expandable metal stents (FCSEMSs) can be effectively placed in patients with benign biliary stricture (BBS). However, stent migration is an inherent problem of FCSEMSs. We evaluated the efficacy of anchoring with a 5F double-pigtail plastic stent (anchoring stent) to prevent migration of an FCSEMS in patients with BBS. Between January 2007 and December 2009, 33 of 37 consecutive patients with BBS who had experienced treatment failure of at least one plastic stent placement were prospectively enrolled in this study. The patients with BBS were randomly assigned to undergo FCSEMS placement with or without an anchoring stent (anchoring group: 16 patients; non-anchoring group: 17 patients). The main outcome measures were the stent migration rate and success rates. The technical success rate was 100% in both groups. Significantly less stent migration occurred in the anchoring group (6.3%, 1/16) than in the non-anchoring group (41.2%, 7/17; P=0.024). The median indwelling time was significantly longer in the anchoring group (154 days; range, 86-176 days) than in the non-anchoring group (114 days; range, 19-162 days; P=0.010). Improvement or resolution of the BBS was confirmed in 15 of 16 patients (93.8%) in the anchoring group, and in 12 of 17 patients (70.6%) in the non-anchoring group (P=0.101). The placement of an anchoring stent appears to be a simple and effective method of preventing premature migration of FCSEMSs in patients with BBS. Appropriately powered studies are needed to confirm this finding.

  4. Use of self-expandable plastic stents for the treatment of esophageal perforations and symptomatic anastomotic leaks.

    PubMed

    Gelbmann, C M; Ratiu, N L; Rath, H C; Rogler, G; Lock, G; Schölmerich, J; Kullmann, F

    2004-08-01

    Extensive anastomotic leaks after esophageal resection and esophageal perforations are a therapeutic challenge. The aim of the present study was to assess the potential of the self-expandable Polyflex plastic stent for the treatment of these conditions. Between January 2002 and March 2003, nine patients were treated with a self-expandable Polyflex plastic stent for sealing of thoracic esophagoenteric anastomotic leaks following surgical resection (n = 5) or esophageal perforation (n = 4). In all patients the stents were inserted successfully without technical problems. In all but two patients complete sealing of the leak was achieved as demonstrated by radiography with water-soluble contrast media. The stent migration rate was 30 % and repositioning of the migrated stents was possible in all cases. Complete mucosal healing of the esophageal leaks and stent extraction was achieved in six patients. The stents were in situ for an average period of 135 +/- 78 days. Two critically ill patients with anastomotic leaks died in spite of stent insertion due to sepsis and one patient with esophageal perforation died due to the underlying malignant disease. Our preliminary experience with the self-expanding and removable Polyflex plastic stent for the sealing of anastomotic leaks and esophageal perforations suggests that this stent is a feasible treatment option, in particular, for more extensive esophageal defects, patients with co-morbid conditions, and critically ill patients.

  5. Primary Self-EXPANDing Nitinol Stenting vs Balloon Angioplasty With Optional Bailout Stenting for the Treatment of Infrapopliteal Artery Disease in Patients With Severe Intermittent Claudication or Critical Limb Ischemia (EXPAND Study).

    PubMed

    Schulte, Karl-Ludwig; Pilger, Ernst; Schellong, Sebastian; Tan, Kong Ten; Baumann, Frederic; Langhoff, Ralf; Torsello, Giovanni; Zeller, Thomas; Amendt, Klaus; Brodmann, Marianne

    2015-10-01

    To compare primary placement of a self-expanding nitinol stent to percutaneous transluminal angioplasty (PTA) with bailout stenting in infrapopliteal arteries of patients with severe intermittent claudication or critical limb ischemia (CLI). In the EXPAND trial (ClinicalTrials.gov; identifier NCT00906022), 92 patients (mean age 72.9±9.5 years; 62 men) undergoing treatment for infrapopliteal stenosis in 11 European centers were randomized 1:1 to either self-expanding nitinol stenting with the Astron Pulsar/Pulsar-18 nitinol stent or PTA with bailout stenting. The primary endpoint was sustainable clinical improvement after 12 months, defined as a ≥1-category increase for Rutherford category 3 patients or a ≥2-category increase for CLI patients (Rutherford categories 4/5) compared with baseline. Furthermore, target lesion revascularization (TLR), mortality, and amputation were assessed after 12 months. Sustained clinical improvement at 1 year was observed in 74.3% of the patients treated with primary stenting and in 68.6% of the patients treated with PTA and bailout stenting (p>0.05). Kaplan-Meier estimates of freedom from TLR (76.6% and 77.6%), mortality (7.4% vs 2.1%), and amputation [8.9% (major 6.7%) vs 13.2% (major 8.7%)] at 1 year were not significantly different. Primary self-expanding nitinol stenting did not show statistically different clinical outcomes compared to angioplasty with bailout stenting for infrapopliteal lesions. © The Author(s) 2015.

  6. Carotid Artery Stenting Using a Novel Self-Expanding Braided Nickel-Titanium Stent: Feasibility and Safety Porcine Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ahlhelm, Frank, E-mail: frah1@gmx.de; Kaufmann, Ralf, E-mail: ralf.kaufmann@vascomed.d; Ahlhelm, Dirk, E-mail: ahlhelmd@gmx.de

    We studied the deliverability and safety of a braided, self-expanding, closed-cell nickel-titanium (NiTi) stent (E-volution, Jotec GmbH, Hechingen, Germany) especially designed for the endovascular treatment of carotid artery bifurcation stenosis with special regard to in-stent stenosis and thrombosis compared with a laser-cut reference nitinol stent in a porcine model of percutaneous vascular interventions. We aimed to assess histopathologic response in minipig carotid and subclavian arteries. Eight minipigs received a total of 42 stents: 14 reference stents and 28 E-volution stents. Eleven of the E-volution stents were additionally coated with heparin. Control angiography was obtained immediately before and after vascular interventionmore » as well as 4 weeks after the procedure. Primary endpoints were 28 days of angiographic analyses as well as histomorphometric analysis, including injury score, inflammation score, luminal diameter, vessel diameter, maximal neointimal thickness, and area of in-stent stenosis. Secondary end points were procedural success, 28-day mortality, and stent thrombosis. All stents could be delivered successfully without procedural complications, morbidity, or mortality during our observation time. As confirmed by histology, no in-stent thrombosis was observed. Compared with common carotid arteries, subclavian arteries are significantly more vulnerable to developing in-stent stenosis caused by neointima proliferation (p < 0.05). Compared with the use of 1 single stent/artery, serial application of two stents leads to a more excessive but not significantly different neointimal proliferation (p > 0.05). The E-volution stent, especially when heparin coated, is in line with the comparison to the laser-cut reference stent displaying similar results of angiographic, histologic, and histomorphometric analyses (p > 0.05). Compared with the reference laser-cut stent, the self-expanding nitinol stent (E-volution) with its advanced braiding

  7. Outcomes of endoscopically inserted self-expandable metal stents in malignancy according to the type of stent and the site of obstruction.

    PubMed

    Jung, Kyoungwon; Ahn, Ji Yong; Jung, Hwoon-Yong; Cho, Charles J; Na, Hee Kyong; Jung, Kee Wook; Lee, Jeong Hoon; Kim, Do Hoon; Choi, Kee Don; Song, Ho June; Lee, Gin Hyug; Kim, Jin-Ho

    2016-09-01

    Self-expandable metal stents (SEMSs) can be used for the palliation of malignant obstruction in the upper gastrointestinal tract. This study assessed the feasibility and efficacy of endoscopically inserted SEMSs for the palliation of malignant obstruction in the stomach and duodenum. Between January 2011 and April 2014, 220 patients with gastric or duodenal obstruction due to malignancy underwent endoscopic SEMS insertion at Asan Medical Center. The associations of technical/clinical outcomes and complications with the type of stent and site of obstruction were analyzed. The 220 patients included 125 men (56.8 %) and 95 women (43.2 %); median patient age was 63 years. Fully covered, partially covered, and uncovered SEMSs were inserted into 16, 77, and 120 patients, respectively. Obstructions were located in the gastric outlet, including the duodenal bulb, in 106 patients, and in the duodenal second and third portions in 114 patients. Technical success was achieved in 213 of 220 patients (96.8 %) and clinical success in 184 of 213 (86.4 %). Clinical success rates were similar to the type of stent, but were significantly greater for gastric outlet (95/104, 91.3 %) than for duodenal (89/109, 81.7 %) obstructions (p = 0.039). Stent migration was observed in 20 patients (9.1 %) and stent obstruction in 51 (23.2 %). Rates of stent migration were significantly higher for fully covered (6/16, 37.5 %) than for partially covered (7/77, 9.1 %) and uncovered (7/120, 5.8 %) SEMSs (p < 0.001) and were significantly higher for gastric outlet (16/104, 15.4 %) than for duodenal (4/109, 1.2 %) obstructions (p = 0.003). Rates of stent obstruction were similar for fully covered (2/16, 12.5 %), partially covered (17/77, 22.1 %), and uncovered (32/120, 26.7 %) SEMSs (p = 0.409) and in patients with gastric outlet (26/104, 25.0 %) and duodenal (25/109, 22.9 %) obstruction (p = 0.724). SEMS selection for malignant obstruction of the upper gastrointestinal

  8. Study design and rationale of the 'Balloon-Expandable Cobalt Chromium SCUBA Stent versus Self-Expandable COMPLETE-SE Nitinol Stent for the Atherosclerotic ILIAC Arterial Disease (SENS-ILIAC Trial) Trial': study protocol for a randomized controlled trial.

    PubMed

    Choi, Woong Gil; Rha, Seung Woon; Choi, Cheol Ung; Kim, Eung Ju; Oh, Dong Joo; Cho, Yoon Hyung; Park, Sang Ho; Lee, Seung Jin; Hur, Ae Yong; Ko, Young Guk; Park, Sang Min; Kim, Ki Chang; Kim, Joo Han; Kim, Min Woong; Kim, Sang Min; Bae, Jang Ho; Bong, Jung Min; Kang, Won Yu; Seo, Jae Bin; Jung, Woo Yong; Cho, Jang Hyun; Kim, Do Hoi; Ahn, Ji Hoon; Kim, Soo Hyun; Jang, Ji Yong

    2016-06-25

    The self-expandable COMPLETE™ stent (Medtronic) has greater elasticity, allowing it to regain its shape after the compression force reduces, and has higher trackability, thus is easier to maneuver through tortuous vessels, whereas the balloon-expandable SCUBA™ stent (Medtronic) has higher radial stiffness and can afford more accurate placement without geographic miss, which is important in aortoiliac bifurcation lesions. To date, there have been no randomized control trials comparing efficacy and safety between the self-expanding stent and balloon-expandable stent in advanced atherosclerotic iliac artery disease. The purpose of our study is to examine primary patency (efficacy) and incidence of stent fracture and geographic miss (safety) between two different major representative stents, the self-expanding nitinol stent (COMPLETE-SE™) and the balloon-expanding cobalt-chromium stent (SCUBA™), in stenotic or occlusive iliac arterial lesions. This trial is designed as a prospective, randomized, multicenter trial to demonstrate a noninferiority of SCUBA™ stent to COMPLETE-SE™ stent following balloon angioplasty in iliac arterial lesions, and a total of 280 patients will be enrolled. The primary end point of this study is the rate of primary patency in the treated segment at 12 months after intervention as determined by catheter angiography, computed tomography angiography, or duplex ultrasound. The SENS-ILIAC trial will give powerful insight into whether the stent choice according to deployment mechanics would impact stent patency, geographic miss, or stent fracture in patients undergoing stent implantation in iliac artery lesions. National Institutes of Health Clinical Trials Registry (ClinicalTrials.gov identifier: NCT01834495 ), registration date: May 8, 2012.

  9. Removal of Retrievable Self-Expandable Metallic Tracheobronchial Stents: An 18-Year Experience in a Single Center.

    PubMed

    Park, Jung-Hoon; Kim, Pyeong Hwa; Shin, Ji Hoon; Tsauo, Jiaywei; Kim, Min Tae; Cho, Young Chul; Kim, Jin Hyoung; Song, Ho-Young

    2016-11-01

    The purpose of the study was to retrospectively evaluate the technical outcomes of removal of retrievable self-expandable metallic stents (REMSs) and identify predictors of technical failure in 81 patients with benign and malignant tracheobronchial strictures. A total of 98 REMSs were removed under fluoroscopic guidance in 81 patients with benign (n = 48) or malignant (n = 33) tracheobronchial strictures. Primary and secondary technical success rates and complication rate were evaluated. Technical outcomes with regard to underlying diseases were also evaluated. Logistic regression models were constructed to identify predictors of primary technical success. Primary and secondary technical success rates were 86.7 and 94.9 %, respectively. Stent removal-related complication rate was 7.1 % (7/98) and all were bleeding after stent removal. All bleeding complications were minor and managed conservatively. Primary technical success rate for benign strictures was significantly lower compared with that for malignant strictures (80.9 vs. 97.1 %, P = 0.029), but secondary technical success rate (93.7 vs. 97.1 %, P = 0.652) did not differ between the two groups. Granulation tissue formation was identified as an independent predictor of primary technical success (odds ratio 0.249, 95 % CI 0.071-0.874, P = 0.030). Removal of REMSs in patients with benign and malignant tracheobronchial strictures is safe and technically feasible. Bronchoscopic guidance may be required when the removal using a hook wire fails. The presence of granulation tissue was the negative predictor of primary technical success.

  10. Management of large bowel obstruction with self-expanding metal stents. A multicentre retrospective study of factors determining outcome.

    PubMed

    Geraghty, J; Sarkar, S; Cox, T; Lal, S; Willert, R; Ramesh, J; Bodger, K; Carlson, G L

    2014-06-01

    UK cancer guidelines recommend patients with colonic obstruction due to suspected malignancy be considered for stenting with a self-expanding metal stent (SEMS). Considerable variation in practice exists due to a lack of expertise, technical difficulties and other, as yet ill-defined features. This retrospective multi-centre study aims to determine the outcome following colonic stenting for large bowel obstruction and identify factors associated with successful intervention. A regional programme of colonic stenting for large bowel obstruction, in five UK centres from 2005 to 2010 was evaluated for outcome including technical and clinical success, survival, complications and reoperation. A SEMS was inserted in 334 patients, including 264 (79.0%) for palliation and 52 (15.6%) as a bridge to surgery. Technical success was achieved in 292 (87.4%) patients, with 46 (13.8%) experiencing a complication or technical failure. Reoperation was required in 39 (14.8%) patients stented for palliation of colorectal cancer of whom 16 (6.1%) subsequently required a colostomy. A one-stage primary anastomosis was achieved in 35 (67.3%) of the 52 patients undergoing stenting as a bridge to resection. Technical success did not vary by indication or site of obstruction (P = 0.60) but was higher for operators who had performed more than 10 procedures (OR 3.34, P = 0.001). ASA grade ≥3 predicted a worse clinical outcome (OR 0.43, P = 0.04). The through-the-scope (TTS) endoscopy technique was more successful than radiological placement alone (90.3% vs 74.8%, P < 0.001). Experienced operators using a TTS technique achieved a better outcome for the emergency management of large bowel obstruction. Older, sicker patients and those with extracolonic and benign strictures fared less well. Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.

  11. A pilot study about the oncologic safety of colonic self-expandable metal stents (SEMS) in obstructive colon cancer: is occlusion always better than "silent" perforation?

    PubMed

    Zanghì, A; Piccolo, G; Cavallaro, A; Pulvirenti, E; Lo Menzo, E; Cardì, F; Di Vita, M; Cappellani, A

    2016-12-01

    To evaluate the oncologic safety of colonic self-expandable metal stents (SEMS) in obstructive colon cancer. We retrospectively reviewed all the patients who were treated with endoscopic placement of a self-expandable metallic stent (SEMS) at our institution. A total of 26 patients were identified during the study period, of which 24 patients (92.30%) were treated with SEMS as a bridge-to-surgery and 2 (7.69%) as palliation. In 22 cases (80.76%), the stenosis was localized to the left side. Clinical success with resolution of bowel obstructions was achieved in 22 (84.61%) patients within a short period of time. Among patients treated successfully with SEMS insertion as bridge to surgery (n = 22), 20 (90.9%) underwent one-stage surgery with primary anastomosis while 2 patients (9.09%) underwent colostomy due to intraoperative evidence of a covered perforation by cancer tissue in the pelvis. Patients with subclinical perforation developed an early peritoneal carcinomatosis, 10 patients treated with curative intent subsequently developed liver metastasis after 24 months. We reported an overall poor outcome among patients treated with the insertion of SEMS. This led us to think that, in some cases, occlusion may be better than a "silent" perforation.

  12. Comparative Study of Esophageal Self-expandable Metallic Stent Insertion and Gastrostomy Feeding for Dysphagia Caused by Lung Cancer.

    PubMed

    Kim, Jihye; Min, Yang Won; Lee, Hyuk; Min, Byung Hoon; Lee, Joon Haeng; Rhee, Poong Lyul; Kim, Jae J

    2018-03-25

    Dysphagia is encountered in a large proportion of patients with lung cancer and is associated with malnutrition and a poor quality of life. This study compared the clinical outcomes of self-expandable metallic stent (SEMS) insertion and percutaneous gastrostomy (PG) feeding for patients with lung cancer and dysphagia. A total of 261 patients with lung cancer, who underwent either SEMS insertion (stent group) or PG (gastrostomy group) as an initial treatment procedure for dysphagia between July 1997 and July 2015 at the Samsung Medical Center, were reviewed retrospectively, and 84 patients with esophageal obstruction were identified. The clinical outcomes, including the overall survival, additional intervention, complications, and post-procedural nutritional status in the two groups, were compared. Among the 84 patients finally analyzed, 68 patients received SEMS insertion and 16 had PG. The stent group had less cervical obstruction and more mid-esophageal obstruction than the gastrostomy group. The Kaplan-Meier curves revealed similar overall survival in the two groups. Multivariate analysis showed that the two modalities had similar survival rates (PG compared with SEMS insertion, hazard ratio 0.682, p=0.219). Fifteen patients (22.1%) in the stent group received additional intervention, whereas there was no case in the gastrostomy group (p=0.063). The decrease in the serum albumin level after the procedure was lower in the gastrostomy group than in the stent group (-0.20±0.54 g/dL vs. -0.65±0.57 g/dL, p=0.013). SEMS insertion and PG feeding for relieving dysphagia by lung cancer had a comparable survival outcome. On the other hand, PG was associated with a better nutritional status.

  13. Self-expanding metallic stent as a bridge to surgery in the treatment of left colon cancer obstruction: Cost-benefit analysis and oncologic results.

    PubMed

    Flor-Lorente, Blas; Báguena, Gloria; Frasson, Matteo; García-Granero, Alvaro; Cervantes, Andrés; Sanchiz, Vicente; Peña, Andres; Espí, Alejandro; Esclapez, Pedro; García-Granero, Eduardo

    2017-03-01

    The use of a self-expanding metallic stent as a bridge to surgery in acute malignant left colonic obstruction has been suggested as an alternative treatment to emergency surgery. The aim of the present study was to compare the morbi-mortality, cost-benefit and long-term oncological outcomes of both therapeutic options. This is a prospective, comparative, controlled, non-randomized study (2005-2010) performed in a specialized unit. The study included 82 patients with left colon cancer obstruction treated by stent as a bridge to surgery (n=27) or emergency surgery (n=55) operated with local curative intention. The main outcome measures (postoperative morbi-mortaliy, cost-benefit, stoma rate and long-term oncological outcomes) were compared based on an "intention-to-treat" analysis. There were no significant statistical differences between the two groups in terms of preoperative data and tumor characteristics. The technically successful stenting rate was 88.9% (11.1% perforation during stent placement) and clinical success was 81.4%. No difference was observed in postoperative morbi-mortality rates. The primary anastomosis rate was higher in the bridge to surgery group compared to the emergency surgery group (77.8% vs. 56.4%; P=.05). The mean costs in the emergency surgery group resulted to be €1,391.9 more expensive per patient than in the bridge to surgery group. There was no significant statistical difference in oncological long-term outcomes. The use of self-expanding metalllic stents as a bridge to surgery is a safe option in the urgent treatment of obstructive left colon cancer, with similar short and long-term results compared to direct surgery, inferior mean costs and a higher rate of primary anastomosis. Copyright © 2017 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Development of tissue-engineered self-expandable aortic stent grafts (Bio stent grafts) using in-body tissue architecture technology in beagles.

    PubMed

    Kawajiri, Hidetake; Mizuno, Takeshi; Moriwaki, Takeshi; Ishibashi-Ueda, Hatsue; Yamanami, Masashi; Kanda, Keiichi; Yaku, Hitoshi; Nakayama, Yasuhide

    2015-02-01

    In this study, we aimed to describe the development of tissue-engineered self-expandable aortic stent grafts (Bio stent graft) using in-body tissue architecture technology in beagles and to determine its mechanical and histological properties. The preparation mold was assembled by insertion of an acryl rod (outer diameter, 8.6 mm; length, 40 mm) into a self-expanding nitinol stent (internal diameter, 9.0 mm; length, 35 mm). The molds (n = 6) were embedded into the subcutaneous pouches of three beagles for 4 weeks. After harvesting and removing each rod, the excessive fragile tissue connected around the molds was trimmed, and thus tubular autologous connective tissues with the stent were obtained for use as Bio stent grafts (outer diameter, approximately 9.3 mm in all molds). The stent strut was completely surrounded by the dense collagenous membrane (thickness, ∼150 µm). The Bio stent graft luminal surface was extremely flat and smooth. The graft wall of the Bio stent graft possessed an elastic modulus that was almost two times higher than that of the native beagle abdominal aorta. This Bio stent graft is expected to exhibit excellent biocompatibility after being implanted in the aorta, which may reduce the risk of type 1 endoleaks or migration. © 2014 Wiley Periodicals, Inc.

  15. Management of pancreatic collections with a novel endoscopically placed fully covered self-expandable metal stent: a national experience (with videos).

    PubMed

    Chandran, Sujievvan; Efthymiou, Marios; Kaffes, Arthur; Chen, John Wei; Kwan, Vu; Murray, Michael; Williams, David; Nguyen, Nam Quoc; Tam, William; Welch, Christine; Chong, Andre; Gupta, Saurabh; Devereaux, Ben; Tagkalidis, Peter; Parker, Frank; Vaughan, Rhys

    2015-01-01

    Recent medical literature on novel lumen-apposing stents for the treatment of pancreatic fluid collections (PFCs) is limited by small numbers, solo operators, and single-center experience. To evaluate a recently developed lumen-apposing, fully covered self-expandable metal stent (FCSEMS) in the management of PFCs. Retrospective case series. Thirteen tertiary and private health care centers across Australia. Forty-seven patients (median age 51 years) who underwent endoscopic management of PFCs. Insertion of FCSEMS after PFC puncture under EUS guidance. A subgroup of 9 patients underwent direct endoscopic necrosectomy. Technical and clinical success rate, adverse event rate. The technical success rate was 53 of 54 patients (98.1%), and the initial clinical success rate was 36 of 47 (76.6%), which was sustained for more than 6 months in 34 of 36 (94.4%). Early adverse events included 4 cases (7.4%) of stent migration during direct endoscopic necrosectomy, 4 cases (7.4%) of sepsis, 1 case (1.9%) of bleeding, and 1 case (1.9%) of stent migration into the fistula tract. Late adverse events were 6 (11.1%) spontaneous stent migrations, 3 (5.6%) recurrent stent occlusions, 3 (5.6%) tissue ingrowth/overgrowth, and 2 (3.7%) bleeding into PFC. The majority of stents inserted (48 of 54, 88.9%) and removed (31 of 35, 88.6%) in our study were described by the operator as superior to pigtail stents with regard to ease of use. Retrospective study. Although FCSEMSs are technically easier to insert and remove compared with traditional pigtail stents, there are significant limitations to the widespread use of FCSEMSs in the management of PFCs. These include cost, adverse events, and lower-than-expected resolution rates. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  16. Placement of a Newly Designed Y-Configured Bilateral Self-Expanding Metallic Stent for Hilar Biliary Obstruction: A Pilot Study.

    PubMed

    Jiao, Dechao; Huang, Kai; Zhu, Ming; Wu, Gang; Ren, Jianzhuang; Wang, Yanli; Han, Xinwei

    2017-01-01

    Whether unilateral or bilateral drainage should be performed for malignant hilar biliary obstruction remains a matter of debate. Although a Y-stent with a central wide-open mesh facilitates bilateral stent placement, it has its own limitations. This study aims to evaluate the feasibility and efficacy of a newly designed Y-configured bilateral self-expanding metallic stent (SEMS) for the treatment of hilar biliary obstruction. In this retrospective study, 14 consecutive patients with unresectable malignant hilar biliary obstruction (Bismuth type II or higher), who underwent placement of a newly designed Y-configured bilateral SEMS for hilar biliary obstruction from April 2013 to March 2015, were included into this study. Data on technical success, clinical success, stent patency, complications and patient survival were collected. Technical and clinical success was 100 and 92.9 %, respectively. Mean serum bilirubin level was significantly decreased 1 month after stent placement (P < 0.01). Furthermore, two patients (14.3 %) had early complications (one patient had severe hemobilia and one patient had cholangitis), and two patients (14.3 %) had late complications (one patient had cholangitis and one patient had cholecystitis). During the mean follow-up period of 298 days (range 89-465 days), six patients (42.9 %) developed stent occlusion caused by tumor ingrowth or overgrowth (n = 5) and sludge (n = 1). Median stent patency and overall survival times were 281 days (95 % CI 175.9-386.1 days) and 381 days (95 % CI 291.4-470.6 days), respectively. The use of the newly designed Y-configured bilateral SEMS is feasible and effective for hilar biliary obstruction using port docking deployment.

  17. Self-expandable metal stents for relieving malignant colorectal obstruction: short-term safety and efficacy within 30 days of stent procedure in 447 patients.

    PubMed

    Meisner, Søren; González-Huix, Ferran; Vandervoort, Jo G; Goldberg, Paul; Casellas, Juan A; Roncero, Oscar; Grund, Karl E; Alvarez, Alberto; García-Cano, Jesús; Vázquez-Astray, Enrique; Jiménez-Pérez, Javier

    2011-10-01

    The self-expandable metal stent (SEMS) can alleviate malignant colonic obstruction and avoid emergency decompressive surgery. To document performance, safety, and effectiveness of colorectal stents used per local standards of practice in patients with malignant large-bowel obstruction to avoid palliative stoma surgery in incurable patients (PAL) and facilitate bowel decompression as a bridge to surgery for curable patients (BTS). Prospective clinical cohort study. Two global registries with 39 academic and community centers. This study involved 447 patients with malignant colonic obstruction who received stents (255 PAL, 182 BTS, 10 no indication specified). Colorectal through-the-scope SEMS placement. The primary endpoint was clinical success at 30 days, defined as the patient's ability to maintain bowel function without adverse events related to the procedure or stent. Secondary endpoints were procedural success, defined as successful stent placement in the correct position, symptoms of persistent or recurrent colonic obstruction, and complications. The procedural success rate was 94.8% (439/463), and the clinical success rates were 90.5% (313/346) as assessed on a per protocol basis and 71.6% (313/437) as assessed on an intent-to-treat basis. Complications included 15 (3.9%) perforations, 3 resulting in death, 7 (1.8%) migrations, 7 (1.8%) cases of pain, and 2 (0.5%) cases of bleeding. No control group. No primary endpoint analysis data for 25% of patients. This largest multicenter, prospective study of colonic SEMS placement demonstrates that colonic SEMSs are safe and highly effective for the short-term treatment of malignant colorectal obstruction, allowing most curable patients to have 1-step resection without stoma and providing most incurable patients minimally invasive palliation instead of surgery. The risk of complications, including perforation, was low. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All

  18. Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents.

    PubMed

    Uthamaraj, Susheil; Tefft, Brandon J; Jana, Soumen; Hlinomaz, Ota; Kalra, Manju; Lerman, Amir; Dragomir-Daescu, Dan; Sandhu, Gurpreet S

    2016-10-26

    Stent-grafts are widely used for the treatment of various conditions such as aortic lesions, aneurysms, emboli due to coronary intervention procedures and perforations in vasculature. Such stent-grafts are manufactured by covering a stent with a polymer membrane. An ideal stent-graft should have a biocompatible stent covered by a porous, thromboresistant, and biocompatible polymer membrane which mimics the extracellular matrix thereby promoting injury site healing. The goal of this protocol is to manufacture a small caliber stent-graft by encapsulating a balloon expandable stent within two layers of electrospun polyurethane nanofibers. Electrospinning of polyurethane has been shown to assist in healing by mimicking native extracellular matrix, thereby promoting endothelialization. Electrospinning polyurethane nanofibers on a slowly rotating mandrel enabled us to precisely control the thickness of the nanofibrous membrane, which is essential to achieve a small caliber balloon expandable stent-graft. Mechanical validation by crimping and expansion of the stent-graft has shown that the nanofibrous polyurethane membrane is sufficiently flexible to crimp and expand while staying patent without showing any signs of tearing or delamination. Furthermore, stent-grafts fabricated using the methods described here are capable of being implanted using a coronary intervention procedure using standard size guide catheters.

  19. Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents

    PubMed Central

    Uthamaraj, Susheil; Tefft, Brandon J.; Jana, Soumen; Hlinomaz, Ota; Kalra, Manju; Lerman, Amir; Dragomir-Daescu, Dan; Sandhu, Gurpreet S.

    2016-01-01

    Stent-grafts are widely used for the treatment of various conditions such as aortic lesions, aneurysms, emboli due to coronary intervention procedures and perforations in vasculature. Such stent-grafts are manufactured by covering a stent with a polymer membrane. An ideal stent-graft should have a biocompatible stent covered by a porous, thromboresistant, and biocompatible polymer membrane which mimics the extracellular matrix thereby promoting injury site healing. The goal of this protocol is to manufacture a small caliber stent-graft by encapsulating a balloon expandable stent within two layers of electrospun polyurethane nanofibers. Electrospinning of polyurethane has been shown to assist in healing by mimicking native extracellular matrix, thereby promoting endothelialization. Electrospinning polyurethane nanofibers on a slowly rotating mandrel enabled us to precisely control the thickness of the nanofibrous membrane, which is essential to achieve a small caliber balloon expandable stent-graft. Mechanical validation by crimping and expansion of the stent-graft has shown that the nanofibrous polyurethane membrane is sufficiently flexible to crimp and expand while staying patent without showing any signs of tearing or delamination. Furthermore, stent-grafts fabricated using the methods described here are capable of being implanted using a coronary intervention procedure using standard size guide catheters. PMID:27805589

  20. Management of postoperative esophageal leaks with the Polyflex self-expanding covered plastic stent.

    PubMed

    Langer, Felix B; Wenzl, Etienne; Prager, Gerhard; Salat, Andreas; Miholic, Johannes; Mang, Thomas; Zacherl, Johannes

    2005-02-01

    Esophageal anastomotic leaks can lead to prolonged hospitalization. In this article we present our experience with the placement of the Polyflex self-expanding plastic stent (Willy Ruesch GMBH, Kernen, Germany) for leak occlusion. Between April 2000 and November 2003, 24 patients were included into this prospective study and underwent Polyflex stent placement for postoperative esophageal anastomotic leaks. The primary operation was esophagectomy in 13 patients, gastrectomy in 7, cardia resection in 2, and other procedures in 2 patients. The median interval between operation and stent placement was 19 days (range, 4 to 65). The effectiveness of leak occlusion was evaluated by water-soluble contrast swallow and the clinical course. In 2 patients stent misplacement produced an enlarged anastomotic dehiscence that necessitated reoperation. Radiologic evaluation was impossible in 4 patients because of their generally restricted condition. Among 18 evaluable patients, leak occlusion was successful with a single stent in 16 patients (89%) based on radiologic evaluation. Immediate oral feeding was well tolerated by these patients. After a median follow-up of 220 days (range, 7 to 1221), 9 cases of late stent dislocation were observed. Stent removal in patients after esophagectomy with gastric pull-up led to dysphagia from anastomotic strictures in 2 patients. Symptomatic strictures did not develop in the 5 evaluable postgastrectomy patients after stent removal. The placement of self-expanding plastic stents is a highly effective treatment for esophageal anastomotic leaks. Because clinically-relevant anastomotic strictures can be expected, we do not recommend stent removal after esophagectomy with gastric pull-up reconstruction.

  1. Use of Self-Expanding Stents for the Treatment of Vertebral Artery Ostial Stenosis: a Single Center Experience

    PubMed Central

    Chung, Sun Young; Choi, Jin Woo; Choi, Byung Se; In, Hyun Sin; Kim, Sun Mi; Choi, Choong Gon; Kim, Sang Joon; Suh, Dae Chul

    2010-01-01

    Objective To evaluate our early experience using self-expanding stents to treat atherosclerotic vertebral artery ostial stenosis (VAOS), with respect to technical feasibility and clinical and imaging follow-up results. Materials and Methods A total of 20 lesions in 20 patients underwent stenting of the VAOS using a self-expanding stent (Precise RX; Cordis Neurovascular, Miami Lakes, FL). Two patients were asymptomatic. We analyzed the technical success rate, causes of technical failure, occurrence of any vascular or neurological event, and the occurrence of any neurological abnormality or in-stent restenosis (ISR) seen on follow-up. The imaging follow-up was performed with Doppler ultrasound (DUS) as a primary screening modality. Results One instance of technical failure was caused by failure of the guidewire passage. The stent diameter was 5 mm, and post-stenting balloon dilatations were necessary in all cases. Stent misplacement requiring placement of an additional stent occurred in four cases. Following a 14.8 month average clinical follow-up time, two patients showed anterior circulation ischemia, which was not attributed to the VAOS we treated. Following a 13.7 month average DUS follow-up, five patients showed a mild degree of diffuse or focal intimal thickening in the stent lumen; however, none of the stenosis showed luminal loss of more than 50% and no stent fracture was noted. Conclusion The use of self-expanding stents for treating VAOS was technically feasible and helped to improve artery patency during our limited follow-up interval. PMID:20191062

  2. Removal of Retrievable Self-Expandable Metallic Tracheobronchial Stents: An 18-Year Experience in a Single Center

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Jung-Hoon; Kim, Pyeong Hwa; Shin, Ji Hoon, E-mail: jhshin@amc.seoul.kr

    2016-11-15

    PurposeThe purpose of the study was to retrospectively evaluate the technical outcomes of removal of retrievable self-expandable metallic stents (REMSs) and identify predictors of technical failure in 81 patients with benign and malignant tracheobronchial strictures.Materials and MethodsA total of 98 REMSs were removed under fluoroscopic guidance in 81 patients with benign (n = 48) or malignant (n = 33) tracheobronchial strictures. Primary and secondary technical success rates and complication rate were evaluated. Technical outcomes with regard to underlying diseases were also evaluated. Logistic regression models were constructed to identify predictors of primary technical success.ResultsPrimary and secondary technical success rates were 86.7 and 94.9 %, respectively.more » Stent removal-related complication rate was 7.1 % (7/98) and all were bleeding after stent removal. All bleeding complications were minor and managed conservatively. Primary technical success rate for benign strictures was significantly lower compared with that for malignant strictures (80.9 vs. 97.1 %, P = 0.029), but secondary technical success rate (93.7 vs. 97.1 %, P = 0.652) did not differ between the two groups. Granulation tissue formation was identified as an independent predictor of primary technical success (odds ratio 0.249, 95 % CI 0.071–0.874, P = 0.030).ConclusionRemoval of REMSs in patients with benign and malignant tracheobronchial strictures is safe and technically feasible. Bronchoscopic guidance may be required when the removal using a hook wire fails. The presence of granulation tissue was the negative predictor of primary technical success.« less

  3. The Safety and efficacy of a new self-expandable intratracheal nitinol stent for the tracheal collapse in dogs

    PubMed Central

    Kim, Joon-young; Han, Hyun-jung; Yun, Hun-young; Lee, Bora; Jang, Ha-young; Eom, Ki-dong; Park, Hee-myung

    2008-01-01

    To evaluate the potential utility of a self-expandable intratracheal nitinol stent with flared ends for the treatment of tracheal collapse in dogs, endotracheal stenting therapy was performed under fluoroscopic guidance in four dogs with severe tracheal collapse. During the 4 to 7 month follow-up, after stent implantation, clinical signs, including dyspnea and respiratory distress, dramatically improved in all dogs. The radiographs showed that the implanted stents improved the tracheal collapse, and there were no side effects such as collapse, shortening or migration of the stents. In conclusion, the self-expandable intratracheal nitinol stents provided adequate stability to the trachea and were effective for attenuating the clinical signs associated with severe tracheal collapse. PMID:18296893

  4. Treatment of nostril and nasal stenosis due to facial burn using a self-expandable metallic esophageal stent.

    PubMed

    Sekine, Kuwon; Matsune, Shoji; Shiiba, Kyoko; Kimura, Maki; Okubo, Kimihiro; Kaneshiro, Tadashi; Tajima, Hiroyuki; Murakami, Masahiro; Kurokawa, Akira

    2015-08-01

    For the treatment of nasal and nostril stenosis caused by facial burn, it is necessary to perform rhinoplasty and nasal vestibuloplasty using various flaps, perform cicatrectomy of the nostrils with a rhinosurgical procedure, and prevent restenosis of the nostrils and nasal cavity for a certain period by methods such as placement of a nasal retainer or transnasal airway and gauze packing of the nasal cavity. With all methods, postoperative placement of a retainer or nasal treatment is necessary for the prevention of postoperative restenosis, and the patient's cooperation is essential. In a patient who did not cooperate in postoperative treatments due to autism and had recurrences of nasal and nostril stenosis after conventional surgical treatments, adequate patency of the nasal cavity and nostrils could be maintained with minimal postoperative treatment by placing a self-expandable metallic esophageal stent. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. The development of self-expanding peripheral stent with ion-modified surface layer

    NASA Astrophysics Data System (ADS)

    Lotkov, Alexander I.; Kashin, Oleg A.; Kudryashov, Andrey N.; Krukovskii, Konstantin V.; Kuznetsov, Vladimir M.; Borisov, Dmitry P.; Kretov, Evgenii I.

    2016-11-01

    In work researches of chemical composition of surface layers of self-expanding stents of nickel-titanium (NiTi) and their functional and mechanical properties after plasma immersion processing by ions of silicon (Si). It is established that in the treatment in the inner and outer surfaces of stents formed doped silicon layer with a thickness of 80 nm. The formation of the doped layer does not impair the functional properties of the stent. At human body temperature, the stent is fully restore its shape after removing the deforming load. The resulting graph of loading of stents during their compression between parallel plates. The research results allow the conclusion that Si-doped stents are promising for treatment of peripheral vascular disease. However, related studies on laboratory animals are required.

  6. Effective treatment of benign biliary strictures with a removable, fully covered, self-expandable metal stent: A prospective, multicenter European study.

    PubMed

    Schmidt, Arthur; Pickartz, Tilman; Lerch, Markus M; Fanelli, Fabrizio; Fiocca, Fausto; Lucatelli, Pierleone; Cereatti, Fabrizio; Hoffmeister, Albrecht; van Steenbergen, Werner; Kraft, Matthias; Meier, Benjamin; Caca, Karel

    2017-04-01

    Temporary placement of removable, fully covered, self-expandable metal stents (fcSEMS) for treatment of benign biliary strictures (BBS) has been reported to be effective. However, the optimal extraction time point remains unclear and stent migration has been a major concern. The objective of this study was to evaluate the efficacy and safety of this treatment modality using an fcSEMS with a special antimigration design and prolonged stent indwell time. We performed a prospective, single-arm study at six tertiary care centers in Europe. Patients with BBS underwent endoscopic or percutaneous implantation of an fcSEMS (GORE® VIABIL® Biliary Endoprosthesis, W.L. Gore & Associates, Flagstaff, AZ, USA). The devices were scheduled to be removed nine months later, and patients were to return for follow-up for an additional 15 months. Forty-three patients were enrolled in the study. Stricture etiology was chronic pancreatitis in the majority of patients (57.5%). All fcSEMS were placed successfully, either endoscopically (76.7%) or percutaneously (23.3%). Stent migration was observed in two patients (5.2%). Primary patency of the SEMS prior to removal was 73.0%. All attempted stent removals were successful. At removal, stricture was resolved or significantly improved without need for further therapy in 78.9% of patients. Stricture recurrence during a follow-up of two years post-implant was observed in two patients. Temporary placement of the fcSEMS is a feasible, safe and effective treatment for BBS. The design of the device used in this study accounts for very low migration rates and facilitates easy stent retrieval, even after it has been in place for up to 11 months.

  7. Effective treatment of benign biliary strictures with a removable, fully covered, self-expandable metal stent: A prospective, multicenter European study

    PubMed Central

    Schmidt, Arthur; Pickartz, Tilman; Lerch, Markus M; Fanelli, Fabrizio; Fiocca, Fausto; Lucatelli, Pierleone; Cereatti, Fabrizio; Hoffmeister, Albrecht; van Steenbergen, Werner; Kraft, Matthias; Meier, Benjamin

    2016-01-01

    Background Temporary placement of removable, fully covered, self-expandable metal stents (fcSEMS) for treatment of benign biliary strictures (BBS) has been reported to be effective. However, the optimal extraction time point remains unclear and stent migration has been a major concern. Objective The objective of this study was to evaluate the efficacy and safety of this treatment modality using an fcSEMS with a special antimigration design and prolonged stent indwell time. Methods We performed a prospective, single-arm study at six tertiary care centers in Europe. Patients with BBS underwent endoscopic or percutaneous implantation of an fcSEMS (GORE® VIABIL® Biliary Endoprosthesis, W.L. Gore & Associates, Flagstaff, AZ, USA). The devices were scheduled to be removed nine months later, and patients were to return for follow-up for an additional 15 months. Results Forty-three patients were enrolled in the study. Stricture etiology was chronic pancreatitis in the majority of patients (57.5%). All fcSEMS were placed successfully, either endoscopically (76.7%) or percutaneously (23.3%). Stent migration was observed in two patients (5.2%). Primary patency of the SEMS prior to removal was 73.0%. All attempted stent removals were successful. At removal, stricture was resolved or significantly improved without need for further therapy in 78.9% of patients. Stricture recurrence during a follow-up of two years post-implant was observed in two patients. Conclusions Temporary placement of the fcSEMS is a feasible, safe and effective treatment for BBS. The design of the device used in this study accounts for very low migration rates and facilitates easy stent retrieval, even after it has been in place for up to 11 months. PMID:28507752

  8. The New Nitinol Conformable Self-Expandable Metal Stents for Malignant Colonic Obstruction: A Pilot Experience as Bridge to Surgery Treatment

    PubMed Central

    2014-01-01

    Introduction. Self-expandable metal stents (SEMS) are a nonsurgical option for treatment of malignant colorectal obstruction also as a bridge to surgery approach. The new nitinol conformable stent has improved clinical outcomes in these kinds of patients. We report a pilot experience with nitinol conformable SEMS placement as bridge to surgery treatment in patients with colorectal obstruction. Materials and Methods. Between April and August 2012, we collected data on colonic nitinol conformable SEMS placement in a cohort of consecutive symptomatic patients, with malignant colorectal obstruction, who were treated as a bridge to surgery. Technical success, clinical success, and adverse events were recorded. Results. Ten patients (7 male (70%)), with a mean age of 69.2 ± 10.1, were evaluated. The mean length of the stenosis was 3.6 ± 0.6 cm. Five patients (50%) were treated on an emergency basis. The median time from stent placement to surgery was 16 days (interquartile range 7–21). Technical and clinical success was achieved in all patients with a significant early improvement of symptoms. No adverse events due to the SEMS placement were observed. Conclusion. This pilot study confirmed the important role of nitinol conformable SEMS as a bridge to surgery option in the treatment of symptomatic malignant colorectal obstruction. PMID:24526914

  9. Mechanical modeling of self-expandable stent fabricated using braiding technology.

    PubMed

    Kim, Ju Hyun; Kang, Tae Jin; Yu, Woong-Ryeol

    2008-11-14

    The mechanical behavior of a stent is one of the important factors involved in ensuring its opening within arterial conduits. This study aimed to develop a mechanical model for designing self-expandable stents fabricated using braiding technology. For this purpose, a finite element model was constructed by developing a preprocessing program for the three-dimensional geometrical modeling of the braiding structure inside stents, and validated for various stents with different braiding structures. The constituent wires (Nitinol) in the braided stents were assumed to be superelastic material and their mechanical behavior was incorporated into the finite element software through a user material subroutine (VUMAT in ABAQUS) employing a one-dimensional superelastic model. For the verification of the model, several braided stents were manufactured using an automated braiding machine and characterized focusing on their compressive behavior. It was observed that the braided stents showed a hysteresis between their loading and unloading behavior when a compressive load was applied to the braided tube. Through the finite element analysis, it was concluded that the current mechanical model can appropriately predict the mechanical behavior of braided stents including such hysteretic behavior, and that the hysteresis was caused by the slippage between the constituent wires and their superelastic property.

  10. No Distal Migration in Unfixed Versus Fixed Cell Structure Covered Self-Expanding Metal Stents for Treatment of Benign Biliary Disease.

    PubMed

    Walter, Dirk; Sarrazin, Christoph; Trojan, Jörg; Kronenberger, Bernd; Bojunga, Jörg; Zeuzem, Stefan; Friedrich-Rust, Mireen; Albert, Jörg G

    2015-08-01

    Fully covered self-expandable metal stents (FCSEMS) are increasingly used for treatment of benign common bile duct (CBD) stricture or leakage, but dislodgement of FCSEMS is frequent. To compare dislocation rate and clinical outcome of a standard fixed cell structure FCSEMS (S-FCSEMS) to a novel FCSEMS with an unfixed cell structure (N-FCSEMS). We performed a retrospective analysis of all patients with FCSEMS insertion for benign biliary disease at our Hospital from 03/2008 to 03/2014. Both stent types N-FCSEMS and S-FCSEMS were applied as available unrelated to the indication. Twenty-nine patients (S-FCSEMS: 18, N-FCSEMS: 11) were included. Stent placement was technically successful in 28/29 (96.6 %) patients; stent removal was successful in 26/27 (96.2 %). Two patients with N-FCSEMS were excluded due to unsuccessful placement and withdrawal of consent for stent removal, respectively. Stent migration into the duodenum (distal migration) was observed in 9/18 (50 %) in the S-FCSEMS group compared to 0/9 in the N-FCSEMS (p < 0.005). FCSEMS migration into the CBD (proximal migration) was found in 2/18 (11 %, S-FCSEMS) versus 2/9 (22 %, N-FCSEMS, p = 0.514). A foreshortening of the N-FCSEMS occurred in 3/9 patients (33 %) compared to 0/18 S-FCSEMS (p = 0.08). Clinical resolution of the treated CBD-disease was observed in 5/9 (56 %, N-FCSEMS) versus 12/18 (67 %, S-FCSEMS) at the time of stent removal (p = 0.604) and in 0/9 and 10/18 (56 %) cases during follow-up, respectively (p < 0.005). An unfixed cell structure of FCSEMS seems to prevent distal migration, but proximal migration still occurs and foreshortening of the N-FCSEMS constrains clinical outcome.

  11. The use of double lasso, fully covered self-expandable metal stents with new "anchoring flap" system in the treatment of benign biliary diseases.

    PubMed

    Mangiavillano, B; Manes, G; Baron, T H; Frego, R; Dinelli, M; Radaelli, F; Teruzzi, V; Amato, A; Pallotta, S; Santoro, T; Masci, E

    2014-09-01

    Many benign biliary diseases (BBD) can be treated with fully covered, self-expandable metal stents (FCSEMS) but stent migration occurs in up to 35.7 %. The aim of this study was to prospectively assess the rate of, safety and effectiveness and stent migration of a new biliary FCSEMS with an anti-migration flap (FCSEMS-AF) in patients with BBD. This was a prospective study from four Italian referral endoscopy centers of 32 consecutive patients (10 females and 22 males; mean age: 60.1 ± 14.8 years; range: 32-84 years) with BBD who were offered endoscopic placement of a FCSEMS-AF as first-line therapy. Were 24 strictures and 8 leaks. Stent placement was technically successful in 32/32 patients (100 %). Immediate clinical improvement was seen in all 32 patients (100 %). One late stent migration occurred (3.3 %). FCSEMS-AF were removed from 30 of the 32 patients (93.7 %) at a mean (± SD) of 124.4 ± 84.2 days (range: 10-386 days) after placement. All patients remained clinically and biochemically well at 1- and 3-month follow-up. One patient (3.3 %) with a post-laparoscopic cholecystectomy stricture developed distal stent migration at 125 days. This new FCSEMS with anti-migration flap seems to be a safe and effective first-line treatment option for patients with BBD.

  12. Midterm to long-term safety and efficacy of self-expandable nitinol stent implantation for coarctation of aorta in adults.

    PubMed

    Haji Zeinali, Ali Mohammad; Sadeghian, Mohammad; Qureshi, Shakeel A; Ghazi, Payam

    2017-09-01

    Endovascular treatment of coarctation of aorta (CoA) by self-expandable Nitinol stents is one of the recognized treatment methods and may be an alternative to surgery or balloon-expandable stent implantation for CoA but there is little information about midterm to long term results of self-expandable stents. Sixty-two patients with CoA (40 men), with a mean age of 30.7 ± 11 years, (range 17-63 years) underwent stent implantation with Optimed self-expandable Nitinol stents between 2005 and 2014. Successful outcome was defined as peak systolic pressure gradient ≤20 mmHg after stent implantation. The patients were followed-up clinically and by echocardiography and in patients, in whom there was suspicion of recoarctation, CT angiography or recatheterization was performed. 65 stents were successfully implanted in all 62 patients. Peak systolic pressure gradient decreased from mean 62.4 ± 18 mmHg (range 35-100 mmHg) to mean 2.8 ± 5 mmHg (range 0-15 mmHg; P < 0.001). Stent displacement occurred in 3 patients during the procedure. These were managed successfully by an overlapping second stent. None of the patients had major complications such as aortic dissection, rupture, or vascular access problems. In follow up, only three patients had recoarctation, and two of these were managed successfully by balloon redilation or further stenting 16 and 18 months after the first procedure and one patient refused reintervention. There were two deaths, unrelated to the procedure, 12 and 78 months after the initial intervention. Follow-up of a mean of 45.5 ± 17 months (range 12-105 months) demonstrated no evidence of aneurysm formation or stent fracture. Self-expandable nitinol stents for the treatment of native and recurrent CoA is safe and has good efficacy with acceptable midterm to long-term outcome. © 2017 Wiley Periodicals, Inc.

  13. Endovascular abdominal aortic stenosis treatment with the OptiMed self-expandable nitinol stent.

    PubMed

    Ghazi, Payam; Haji-Zeinali, Ali-Mohammad; Shafiee, Nahid; Qureshi, Shakeel A

    2009-10-01

    To evaluate the safety and feasibility of self-expandable stents (OptiMed) for treatment of abdominal aortic stenosis in the situations in which the aortic stenosis locates near the origin of celiac, superior mesenteric, renal and inferior mesenteric arteries. Five consecutive patients scheduled for endovascular treatment of abdominal aortic stenosis by self-expandable nitinol stent (Sinus-Aorta/OptiMed) implantation. The diameter of the stent was chosen as 10-30% more than that of the normal portion of the aorta above the stenosis. Long stents of 60 mm or longer were chosen. After stent deployment, balloon postdilation was performed with a balloon in patients with residual gradient > 5 mm Hg. All patients were successfully treated with the OptiMed stents. The balloon predilation was performed in one patient due to severe stenosis. The mean diameter and length of the stents deployed were 20.4 +/- 2.9 (range, 16-24 mm) and 64 +/- 8.9 (range, 60-80 mm), respectively. The balloon postdilation was performed in all cases. The mean diameter of the balloons was 13.6 +/- 1.5 (range, 12-15 mm). The mean diameter of stenosis increased from 4.8 +/- 1.9 to 14.4 +/- 1.8 mm after stent placement. The mean peak systolic gradient decreased from 46.8 +/- 31.5 mm Hg to 0.8 +/- 1.8 mm Hg. During follow-up (22.8 +/- 14.3 months), none of the patients had restenosis within the stent, occlusion of any branches of the aorta, or other related complications. In our small series, we observed that abdominal aortic stenosis can be successfully and effectively treated with OptiMed stents in the situations in which the stenotic segment is located next to the origins of the main visceral branches of abdominal aorta.

  14. Preoperative biliary drainage by plastic or self-expandable metal stents in patients with periampullary tumors: results of a randomized clinical study

    PubMed Central

    Olsson, Greger; Frozanpor, Farshad; Lundell, Lars; Enochsson, Lars; Ansorge, Christoph; Del Chiaro, Marco; Reuterwall-Hansson, Marcus; Shetye, Alysha; Arnelo, Urban

    2017-01-01

    Background and study aims  Preoperative biliary drainage in patients with periampullary tumors and jaundice has been popularized to improve the quality of life and minimize the risks associated with subsequent radical surgery. The aim of this study was to investigate the possible superiority of self-expandable metal stents (SEMS) over plastic stents, by comparing the amount of bacteria in intraoperatively collected bile and using this variable as a proxy for the efficacy of the respective biliary drainage modalities. Patients and methods  In this randomized clinical trial, 92 patients with obstructive jaundice were enrolled; 45 were allocated to the plastic stent group and 47 to the SEMS group. The primary outcome was the extent and magnitude of biliary bacterial growth at the time of surgical exploration. Secondary outcomes were: macroscopic grading of inflammation of the stented bile ducts, occurrence of adverse events after stenting, stent dysfunction, recognized surgical complexities, and incidence of postoperative complications. Results  The patients were well matched regarding clinical and disease-specific characteristics. At surgery, there were no group differences in the bacterial amount and composition of the bile cultures or the perceived difficulty of surgical dissection. During the preoperative biliary drainage period, more instances of stent dysfunction requiring stent replacement were recorded in the plastic stent group (19 % vs. 0 %; P  = 0.03). Postoperative complications in patients who underwent curative surgery were more common in patients with plastic stents (72 % vs. 52 %), among which clinically significant leakage from the pancreatic anastomoses seemed to predominate (12 % vs. 3.7 %); however, none of these differences in postoperative adverse events reached statistical significance. Conclusion  This randomized clinical study was unable to demonstrate any superiority of SEMS in the efficacy of preoperative bile

  15. Successful management of a benign anastomotic colonic stricture with self-expanding metallic stents: A case report

    PubMed Central

    Guan, Yong-Song; Sun, Long; Li, Xiao; Zheng, Xiao-Hua

    2004-01-01

    AIM: To assess the effectiveness of and complications associated with metallic stent placement for treatment of anastomotic colonic strictures. METHODS: A 46-year-old man underging two procedures of surgery for perforation of descending colon due to a traffic accident presented with pain, abdominal distention, and inability to defecate. Single-contrast barium enema radiograph showed a severe stenosis in the region of surgical anastomosis and the patient was too weak to accept another laparotomy. Under fluoroscopic and endoscopic guidance, we placed two metallic stents in the stenosis site of the anastomosis of the patient with anastomotic colonic strictures. RESULTS: In this case of postsurgical stenosis, the first stent relieved the symptoms of obstruction, but stent migration happened on the next day so an additional stent was required to deal with the stricture and relieve the symptoms. CONCLUSION: This case confirms that metallic stenting may represent an effective treatment for anastomotic colonic strictures in the absence of other therapeutic alternatives. PMID:15526381

  16. Self-expanding stent effects on radiation dosimetry in esophageal cancer.

    PubMed

    Francis, Samual R; Anker, Christopher J; Wang, Brian; Williams, Greg V; Cox, Kristen; Adler, Douglas G; Shrieve, Dennis C; Salter, Bill J

    2013-07-08

    It is the purpose of this study to evaluate how self-expanding stents (SESs) affect esophageal cancer radiation planning target volumes (PTVs) and dose delivered to surrounding organs at risk (OARs). Ten patients were evaluated, for whom a SES was placed before radiation. A computed tomography (CT) scan obtained before stent placement was fused to the post-stent CT simulation scan. Three methods were used to represent pre-stent PTVs: 1) image fusion (IF), 2) volume approximation (VA), and 3) diameter approximation (DA). PTVs and OARs were contoured per RTOG 1010 protocol using Eclipse Treatment Planning software. Post-stent dosimetry for each patient was compared to approximated pre-stent dosimetry. For each of the three pre-stent approximations (IF, VA, and DA), the mean lung and liver doses and the estimated percentages of lung volumes receiving 5 Gy, 10 Gy, 20 Gy, and 30 Gy, and heart volumes receiving 40 Gy were significantly lower (p-values < 0.02) than those estimated in the post-stent treatment plans. The lung V5, lung V10, and heart V40 constraints were achieved more often using our pre-stent approximations. Esophageal SES placement increases the dose delivered to the lungs, heart, and liver. This may have clinical importance, especially when the dose-volume constraints are near the recommended thresholds, as was the case for lung V5, lung V10, and heart V40. While stents have established benefits for treating patients with significant dysphagia, physicians considering stent placement and radiation therapy must realize the effects stents can have on the dosimetry.

  17. Treatment of Malignant Biliary Obstruction with a PTFE-Covered Self-Expandable Nitinol Stent

    PubMed Central

    Kwak, Hyo-Sung; Jin, Gong-Yong; Lee, Seung-Ok; Chung, Gyung-Ho

    2007-01-01

    Objective We wanted to determine the technical and clinical efficacy of using a PTFE-covered self-expandable nitinol stent for the palliative treatment of malignant biliary obstruction. Materials and Methods Thirty-seven patients with common bile duct strictures caused by malignant disease were treated by placing a total of 37 nitinol PTFE stents. These stents were covered with PTFE with the exception of the last 5 mm at each end; the stent had an unconstrained diameter of 10 mm and a total length of 50-80 mm. The patient survival rate and stent patency rate were calculated by performing Kaplan-Meier survival analysis. The bilirubin, serum amylase and lipase levels before and after stent placement were measured and then compared using a Wilcoxon signed-rank test. The average follow-up duration was 27.9 weeks (range: 2-81 weeks). Results Placement was successful in all cases. Seventy-six percent of the patients (28/37) experienced adequate palliative drainage for the remainder of their lives. There were no immediate complications. Three patients demonstrated stent sludge occlusion that required PTBD (percutaneous transhepatic biliary drainage) irrigation. Two patients experienced delayed stent migration with stone formation at 7 and 27 weeks of follow-up, respectively. Stent insertion resulted in acute elevations of the amylase and lipase levels one day after stent insertion in 11 patients in spite of performing endoscopic sphincterotomy (4/6). The bilirubin levels were significantly reduced one week after stent insertion (p < 0.01). The 30-day mortality rate was 8% (3/37), and the survival rates were 49% and 27% at 20 and 50 weeks, respectively. The primary stent patency rates were 85%, and 78% at 20 and 50 weeks, respectively. Conclusion The PTFE-covered self-expandable nitinol stent is safe to use with acceptable complication rates. This study is similar to the previous studies with regard to comparing the patency rates and survival rates. PMID:17923784

  18. Efficacy of a Self-Expandable Porous Stent as the Sole Curative Treatment for Extracranial Carotid Pseudoaneurysms.

    PubMed

    Chen, Peng Roc; Edwards, Nancy J; Sanzgiri, Aditya; Day, Arthur L

    2016-04-01

    Extracranial carotid pseudoaneurysms are uncommon vascular lesions. Even with conservative management complications can happen, such as delayed cerebral embolization or symptoms due to flow limitation. Although endovascular therapy can be curative, literature demonstrating a preferred technique is scant. Our goal was to evaluate the use of 1 technique only-the deployment of overlapping self-expandable porous stents-to treat a series of extracranial carotid pseudoaneurysms. From 2008 to 2014, 14 consecutive cases of symptomatic extracranial carotid pseudoaneurysms were managed with single or multilayer porous stents at our institution. Each patient underwent a standardized angiographic follow-up at 6 months. Twelve patients also received a follow-up computed tomography angiogram at 12 months, and yearly thereafter (median radiographic follow-up, 38 months). The total clinical follow-up period ranged between 6 and 69 months (median, 46 months). In our series, each of the extracranial carotid pseudoaneurysms appeared to be the result of carotid artery dissection with associated carotid stenosis at the origin of every pseudoaneurysm. Endovascular treatment consisted of 1-3 layers of self-expandable porous stents placed without balloon angioplasty. Immediately after stenting angiographic images were notable for stagnant opacification of the pseudoaneurysm through the stent(s). All pseudoaneurysms were completely obliterated by the 6-month follow-up angiogram and remained so throughout the radiographic follow-up period. Complications were minimal, consisting of 1 patient developing a mild Horner's syndrome after treatment that resolved during clinical follow-up. Extracranial carotid pseudoaneurysms can be successfully obliterated with the use of porous, self-expandable stents. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Use of a balloon-expandable metallic stent for treatment of nasopharyngeal stenosis in dogs and cats: six cases (2005-2007).

    PubMed

    Berent, Allyson C; Weisse, Chick; Todd, Kimberly; Rondeau, Mark P; Reiter, Alexander M

    2008-11-01

    To determine outcome associated with use of a balloon-expandable metallic stent for treatment of nasopharyngeal stenosis in dogs and cats. Retrospective case series. 3 dogs and 3 cats. All 6 animals had severe inspiratory stertor at initial examination. Two animals had no orifice present at the stenosis. Nasopharyngeal stenosis was diagnosed and stent size determined by use of computed tomography. A percutaneous transluminal angioplasty balloon premounted with a balloon-expandable metallic stent was placed over a guidewire, advanced through the stenotic lesion under fluoroscopic and rhinoscopic guidance, and dilated to restore patency. All animals had immediate resolution of clinical signs after stent placement. The procedure took a median of 38 minutes (range, 22 to 70 minutes). One animal with a stenosis located far caudally needed the tip of the stent resected because of hairball entrapment and exaggerated swallowing. Both animals without an orifice in the stenosis had tissue in-growth requiring a covered stent. All animals were reexamined 6 to 12 weeks after treatment via rhinoscopy, radiography, computed tomography, or a combination of techniques. All animals lacked signs of discomfort; 5 of 6 were breathing normally 12 to 28 months after the procedure. Transnasal balloon-expandable metallic stent placement may represent a rapid, safe, noninvasive, and effective treatment in animals with nasopharyngeal stenosis. If the stenosis is extremely caudal in the nasopharynx, serial balloon dilatation might be considered prior to stent placement. A covered stent should be considered initially if the stenosis is completely closed.

  20. Comparison of the utility of covered metal stents versus uncovered metal stents in the management of malignant biliary strictures in 749 patients.

    PubMed

    Lee, Jeffrey H; Krishna, Somashekar G; Singh, Amanpal; Ladha, Harshad S; Slack, Rebecca S; Ramireddy, Srinivas; Raju, Gottumukkala S; Davila, Marta; Ross, William A

    2013-08-01

    Self-expandable metal stents (SEMSs) are used to relieve malignant biliary obstruction. To compare outcomes between covered self-expandable metal stents (CSEMSs) and uncovered self-expandable metal stents (USEMSs) in malignant biliary obstruction. Retrospective cohort study. Tertiary cancer center. Patients with malignant biliary obstruction. Placement of CSEMS or USEMS. Time to recurrent biliary obstruction (TRO), overall survival (OS), and adverse events. From January 2000 to June 2011, 749 patients received SEMSs: 171 CSEMSs and 578 USEMSs. At 1 year, there was no significant difference in the percentage of patients with recurrent obstruction (CSEMSs, 35% vs USEMSs, 38%) and survival (CSEMSs, 45% vs USEMSs, 49%). There was no significant difference in the median OS (CSEMSs, 10.4 months vs USEMSs, 11.8 months; P = .84) and the median TRO (CSEMSs, 15.4 months vs USEMSs, 26.3 months; P = .61). The adverse event rate was 27.5% for the CSEMS group and 27.7% for the USEMS group. Although tumor ingrowth with recurrent obstruction was more common in the USEMS group (76% vs 9%, P < .001), stent migration (36% vs 2%, P < .001) and acute pancreatitis (6% vs 1%, P < .001) were more common in the CSEMS group. Retrospective study. There was no significant difference in the patency rate or overall survival between CSEMSs and USEMSs for malignant distal biliary strictures. The CSEMS group had a significantly higher rate of migration and pancreatitis than the USEMS group. No significant SEMS-related adverse events were observed in patients undergoing neoadjuvant chemoradiation or surgical resection. Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  1. Endoscopic treatment of large pancreatic fluid collections (PFC) using self-expanding metallic stents (SEMS) - a two-center experience.

    PubMed

    Chaves, Dalton Marques; Mönkemüller, Klaus; Carneiro, Fred; Medrado, Bruno; Dos Santos, Marcos; Wodak, Stephanie; Reimão, Sílvia; Sakai, Paulo; de Moura, Eduardo

    2014-12-01

    Background/study aim: During the last several years, endoscopic ultrasound (EUS)-guided pancreatic fluid collections' (PFC) drainage has evolved into the preferred drainage technique. Recently, self-expanding metallic stents (SEMS) have been used as an alternative to double pigtail stents, with the advantage of providing a larger diameter fistula, thereby decreasing the risk of early obstruction and also allowing for direct endoscopic exploration of the cavity. The aim of this study was to evaluate the technical and clinical success, safety, and outcome of patients undergoing EUS-guided drainage of complex PFC using SEMS. The study was conducted at two tertiary hospitals from January 2010 to January 2013. All patients with PFC referred for endoscopic drainage were enrolled in a prospective database. The inclusion criteria were: (1) patients with pseudocysts or walled-off necrosis based on the revised Atlanta classification; (2) symptomatic patients with thick PFC; (3) PFC that persisted more than 6 weeks; and (4) large PFC diameter (≥ 9 cm). The exclusion criteria consisted of coagulation disorders, PFC bleeding or infection, and failure-to-inform written consent. A total of 16 patients (9 females, 7 males; mean age 52.6, range 20 - 82) underwent EUS drainage with SEMS. There were 14 cases of pseudocysts and 2 cases of walled-off necrosis. The etiologies of the PFC were mainly gallstones (8 of 16 patients, 50 %) and alcohol (5 of 16 patients, 31 %). Technical success was achieved in 100 % of the cases. All patients had a complete resolution of the PFC. Transmural EUS-guided drainage of complex PFC using SEMS is feasible, appears safe, and is efficacious. However, the exchange of the UC (uncovered)-SEMS for plastic stents is mandatory within 1 week. Future prospective studies, preferably multicenter studies, comparing SEMS versus traditional plastic stents for the drainage of PFC are warranted.

  2. Efficacy of different types of self-expandable stents in carotid artery stenting for carotid bifurcation stenosis.

    PubMed

    Liu, Ya-min; Qin, Hao; Zhang, Bo; Wang, Yu-jing; Feng, Jun; Wu, Xiang

    2016-02-01

    Both open and closed loop self-expandable stents were used in carotid artery stenting (CAS) for carotid bifurcation stenosis. We sought to compare the efficacy of two types of stents in CAS. The data of 212 patients treated with CAS (42 and 170 cases implanted with closed and open loop stents, respectively) for carotid bifurcation stenosis and distal filtration protection devices were retrospectively analyzed. Between closed and open loop stents, there were no significant differences in hospitalization duration, NIHSS score before and after the treatment, stenosis at 12th month, and cumulative incidence of primary endpoint events within 30 days or from the 31st day to the 12th month; while there were significant differences in hemodynamic changes and rate of difficulty in recycling distal filtration protection devices. Use of open vs. closed loop stents for carotid bifurcation stenosis seems to be associated with similar incidence of complications, except for greater rate of hemodynamic changes and lower rate of difficulty in recycling the distal filtration protection devices.

  3. Plastic vs. Self-Expandable Metal Stents for Palliation in Malignant Biliary Obstruction: A Series of Meta-Analyses.

    PubMed

    Almadi, Majid A; Barkun, Alan; Martel, Myriam

    2017-02-01

    Self-expandable metal stents (SEMS) are thought to have an advantage over plastic stents in achieving biliary drainage. We performed a systematic search of MEDLINE, EMBASE, Scopus, CENTRAL, and ISI Web of knowledge databases, from January 1980 to September 2015, for randomized-controlled trials (RCTs) comparing SEMS vs. plastic stents in the palliation of malignant biliary obstruction. Primary outcomes were durations of stent patency, patient survival, and 30-day mortality. Numerous secondary outcomes were assessed, and extensive sensitivity and subgroup analyses were performed. In all, 20 RCTs totaling 1,713 patients yielded a weighted mean difference (WMD) in time to stent patency (4 studies) of 4.45 months (95% confidence interval (CI), 0.31, 8.59; GRADE=moderate) favoring SEMS. There were no differences in overall patient survival (5 studies) WMD=0.67 months (95% CI, -0.66, 1.99; GRADE=moderate), or 30-day mortality (8 studies) odds ratio (OR)=0.80 (95% CI, 0.52, 1.24; GRADE=moderate) but there was a higher symptom-free survival at 6 months (4 studies) OR=5.96 (95% CI, 1.71, 20.81; GRADE=moderate). SEMS use resulted in lower rates of late complications (11 studies) OR=0.43 (95% CI, 0.26, 0.71; GRADE=moderate), sepsis or cholangitis (14 studies) OR=0.53 (95% CI, 0.37, 0.77; GRADE=high), blocking from sludge (8 studies) OR=0.11(95% CI, 0.07, 0.17; GRADE=moderate), and mean number of re-interventions (8 studies) WMD=-0.83 interventions (95% CI, -1.64, -0.02; GRADE=moderate). There was a longer patency of SEMS for those without a prior drainage attempt (2 studies) WMD 7.70 months (95% CI, 7.14, 8.25; GRADE=high). Although a survival advantage was found when an uncovered SEMS was used (3 studies) WMD 1.31 months (95% CI, 0.30, 2.32; GRADE=high), but not partially or fully covered SEMS (2 studies) WMD -0.66 months (95% CI, -1.02, -0.30; GRADE=high) vs. plastic stents, and for SEMS in the setting of pre- or post-procedural antibiotic administration (2 studies) WMD 1

  4. Feasibility of placing a modified fully covered self-expandable metal stent above the papilla to minimize stent-induced bile duct injury in patients with refractory benign biliary strictures (with videos).

    PubMed

    Moon, Jong Ho; Choi, Hyun Jong; Koo, Hyun Cheol; Han, Seung Hyo; Lee, Tae Hoon; Cho, Young Deok; Park, Sang-Heum; Kim, Sun-Joo

    2012-05-01

    Endoscopic placement of fully covered self-expandable metal stents (FCSEMS) has been attempted to manage benign biliary strictures, but currently available FCSEMSs may be associated with unintended complications, including de novo strictures, in patients with normal life expectancy. To evaluate the feasibility of an intraductally placed modified FCSEMS to minimize stent-induced bile duct injury in patients with benign biliary strictures. Prospective observational clinical feasibility study. Tertiary-care academic center. This study involved 21 patients with symptomatic benign biliary strictures in whom conventional endoscopic management failed. Strictured segments were 15 mm above the ampulla of Vater. The modified FCSEMS has convex margins, a lasso, and an anti-migrating waist on the central portion. Stents were placed entirely above the papilla and removed after 3 to 5 months. Success, complications, removability, midterm outcome. FCSEMSs were successfully placed inside the bile duct in all patients. No episodes of pancreatitis, cholangitis, or sepsis were noted during the stenting period. Stent migration occurred in 4 patients (19.0%), but 3 were asymptomatic during follow-up. All stents were removed successfully with rat-tooth forceps without complications. Post-stenting cholangiograms showed improvement of strictures in 20 of 21 patients, without de novo focal stricture. The clinical success rate was 95.2%, with one recurrent stricture. The small number and lack of comparison with other types of FCSEMSs. Temporary intraductal placement of a newly modified FCSEMS effectively improved strictures and prevented potential stent-induced complications in patients with benign biliary strictures. Controlled large-scale trials are needed to confirm the long-term efficacy. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  5. Outcome of self-expandable metallic stent deployment in patients with malignant gastroduodenal outlet obstruction and Niti-S and WallFlex comparison: a multicenter retrospective clinical study.

    PubMed

    Kato, Hironari; Kawamoto, Hirofumi; Matsumoto, Kazuya; Moriyama, Ichiro; Kamada, Hideki; Tsutsumi, Koichiro; Goto, Daisuke; Fukuba, Nobuhiko; Kato, Kiyohito; Sonoyama, Hiroki; Isomoto, Hajime; Okada, Hiroyuki

    2016-08-01

    Several studies report on the outcomes of self-expandable metallic stents (SEMSs) deployment for malignant gastric outlet obstruction (GOO). However, data was mostly based on the analysis of single-center studies including only a small number of patients. This study aimed to evaluate clinical outcomes after the deployment of SEMS in patients with malignant GOO and to compare the clinical outcomes of two metallic stents with different designs. Altogether 125 consecutive patients from five institutions were included. Clinical outcomes were evaluated according to technical success, clinical success, stent patency period, survival period and complications. A comparison of clinical outcomes between Niti-S pyloric/duodenal and WallFlex duodenal stents was also undertaken. Rates for clinical and technical success were 100% and 92.0%, respectively. The median stent patency and survival periods were 72.0 days (range 3-775 days) and 75.0 days (range 3-775 days), respectively. The rate of overall adverse events was 28.8%. The rate of stent dysfunction was 16.8%, and that of adverse events, except stent dysfunction was 12.0%. Massive bleeding occurred in two patients as a late complication. The clinical success rate for Niti-S stent was significantly higher than that for WallFlex stent (96.2% vs 84.8%, P = 0.023). We successfully deployed a SEMS in malignant GOO. The selection of a SEMS with a lower axial force may be important for patients to resume the oral food intake. Additionally, consideration must be given to the appropriate management of fatal bleeding as a late complication. © 2016 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

  6. Biodegradable shape-memory block co-polymers for fast self-expandable stents.

    PubMed

    Xue, Liang; Dai, Shiyao; Li, Zhi

    2010-11-01

    Block co-polymers PCTBVs (M(n) of 36,300-65,300 g/mol, T(m) of 39-40 and 142 degrees C) containing hyperbranched three-arm poly(epsilon-caprolactone) (PCL) as switching segment and microbial polyester PHBV as crystallizable hard segment were designed as biodegradable shape-memory polymer (SMP) for fast self-expandable stent and synthesized in 96% yield by the reaction of three-arm PCL-triol (M(n) of 4200 g/mol, T(m) of 47 degrees C) with methylene diphenyl 4,4'-diisocyanate isocynate (MDI) to form the hyperbrached MDI-linked PCL (PTCM; M(n) of 25,400 g/mol and a T(m) of 38 degrees C), followed by further polymerization with PHBV-diol (M(n) of 2200 g/mol, T(m) of 137 and 148 degrees C). The polymers were characterized by (1)H NMR, GPC, DSC, tensile test, and cyclic thermomechanical tensile test. PCTBVs showed desired thermal properties, mechanical properties, and ductile nature. PCTBV containing 25 wt% PHBV (PCTBV-25) demonstrated excellent shape-memory property at 40 degrees C, with R(f) of 94%, R(r) of 98%, and shape recovery within 25s. PCTBV-25 was also shown as a safe material with good biocompatibility by cytotoxicity tests and cell growth experiments. The stent made from PCTBV-25 film showed nearly complete self-expansion at 37 degrees C within only 25 s, which is much better and faster than the best known self-expandable stents. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  7. Systematic review of self-expanding stents in the management of benign colorectal obstruction.

    PubMed

    Currie, A; Christmas, C; Aldean, H; Mobasheri, M; Bloom, I T M

    2014-04-01

    Colorectal obstruction due to benign disease is likely to become more prevalent. Self-expanding stents have been shown to be effective in reducing morbidity and allowing one-stage resection or improved palliation in colorectal cancer. This review assessed the use of self-expanding stents in benign colorectal obstruction. A systematic review was performed using PubMed, Embase and the Cochrane Library. Keywords included: 'benign disease' 'colorectal obstruction', 'stent', 'endoprosthesis' and 'prosthesis' Original articles from all relevant listings were sourced. These were hand searched for further articles of relevance. The main outcome measures assessed were technical and clinical success, perforation, reobstruction and stoma avoidance in the bridge to surgery population. The search strategy identified 130 articles; the 21 included studies yielded a pooled analysis of 122 patients. Diverticulitis was the predominant aetiology (66/122, 54%). Technical success was achieved in 115/122 (94%) and clinical success in 108/120 (87%) patients. Overall, the perforation rate was 12% (15/122) and the reobstruction rate was 14% (17/122). A stoma was avoided in 48% (23/48) of bridge to surgery patients. Perforation and stoma avoidance in the bridge to surgery group were worse with an aetiology of diverticulitis. Complication rates in stenting for benign colorectal obstruction are higher than for malignant obstruction. On the basis of limited published evidence, stenting cannot be recommended for benign colorectal obstruction. Colorectal Disease © 2013 The Association of Coloproctology of Great Britain and Ireland.

  8. Evolution of patency rates of self-expandable bare metal stents for endovascular treatment of femoro-popliteal arterial occlusive disease: Does stent design matter?

    PubMed

    Treitl, Karla Maria; Woerner, Benedikt; Schinner, Regina; Czihal, Michael; Notohamiprodjo, Susan; Hoffmann, Ulrich; Treitl, Marcus

    2017-09-01

    To analyse the patency rates of femoro-popliteal stenting with different self-expandable Nitinol stent-designs. Two hundred and twenty-two patients (142 (64%) male; age 72.4 ± 11.6 years) with symptomatic femoro-popliteal peripheral arterial occlusive disease (PAOD) underwent percutaneous transluminal angioplasty (PTA) and stenting with three different Nitinol stents (interwoven IW: n = 70; closed-cell CC: n = 85; open-cell OC: n = 67). One-year post-procedural target lesion revascularization (TLR_12M) rates were investigated with regard to co-morbidities: diabetes (DBM), hyperlipidaemia (HLP), hypertension (RR), coronary artery disease (CAD) and degree of calcification. Twelve-month follow-up data were available for 60, 69 and 50 patients in the IW, OC and CC groups (179 patients in total). The cumulative patency (IW: 52 (86.7%); OC: 50 (72.5%); CC: 23 (46.0%); P < 0.001) and the TLR_12M rates (IW: 8 (13.3%); OC: 19 (27.5%); CC: 27 (54.0%); P < 0.001) differed significantly, as did the subgroup analyses (DBM: P = 0.05; RR: P = 0.003; HLP: P = 0.005; CAD: P = 0.02; localization: P < 0.001; calcification: P < 0.001), with the best patency for the IW stent and the highest TLR_12M for the CC stent. The interwoven stent-design was superior to the standard open- and closed-cell stent-designs in endovascular treatment of femoro-popliteal PAOD in a follow-up period of 12 months. • Results of femoro-popliteal stenting are still unsatisfactory. • Comparative studies for currently available different Nitinol stent-designs are lacking. • This is a first comparative study on long-term patency of different Nitinol stent-designs. • Interwoven stent-design leads to improved long-term patency. • Interwoven stent-design leads to lower TLR than other stent-designs.

  9. Modified fully covered self-expandable metal stents with antimigration features for benign pancreatic-duct strictures in advanced chronic pancreatitis, with a focus on the safety profile and reducing migration.

    PubMed

    Moon, Sung-Hoon; Kim, Myung-Hwan; Park, Do Hyun; Song, Tae Joon; Eum, Junbum; Lee, Sang Soo; Seo, Dong Wan; Lee, Sung Koo

    2010-07-01

    Fully covered self-expandable metal stent (FCSEMS) placement has recently been tried in the management of refractory pancreatic-duct strictures associated with advanced chronic pancreatitis. The major limitation of FCSEMSs was frequent migration. To assess the safety, migration rate, and removability of modified FCSEMSs with antimigration features used for the treatment of benign pancreatic-duct strictures. Prospective study. Tertiary academic center. Thirty-two patients with chronic painful pancreatitis and dominant ductal stricture. Transpapillary endoscopic placement of FCSEMSs in the pancreatic duct with removal after 3 months. Technical and functional success and adverse events associated with the placement of metal stents. FCSEMSs were successfully placed in all patients through the major (n = 27) or minor (n = 5) duodenal papilla. All patients achieved pain relief from stent placement. There was no occurrence of stent-induced pancreatitis or pancreatic sepsis. No stent migrated, and all stents were easily removed. Follow-up ERCP 3 months after stent placement showed resolution of duct strictures in all patients. Pancreatograms obtained at FCSEMS removal displayed de novo focal pancreatic duct strictures in 5 patients, but all were asymptomatic. No long-term follow-up. Temporary 3-month placement of FCSEMSs was effective in resolving pancreatic-duct strictures in chronic pancreatitis, with an acceptable morbidity profile. Modified FCSEMSs can prevent stent migration, but may be associated with de novo duct strictures. Further trials are needed to assess long-term safety and efficacy. Copyright 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  10. Management of acute cholangitis as a result of occlusion from a self-expandable metallic stent in patients with malignant distal and hilar biliary obstructions.

    PubMed

    Shiomi, Hideyuki; Matsumoto, Kazuya; Isayama, Hiroyuki

    2017-04-01

    Acute cholangitis as a result of common bile duct stones can be managed; however, cholangitis caused by occlusion with a biliary self-expandable metallic stent (SEMS) in patients with an unresectable malignant biliary obstruction has not been fully discussed. The acute cholangitis clinical guidelines (Tokyo Guidelines 2013) recommend following the same procedure as that used for cholangitis; however, the patient's condition, including performance status, tumor extension or staging, and prognosis must be considered. Most physicians manage cholangitis from a SEMS occlusion using a two-step procedure. They insert endoscopic drainage with a plastic stent or insert a nasobiliary drainage tube, which does not exacerbate sepsis. Addition or replacement of a biliary SEMS is required in many cases depending on the cause of the occlusion. Tumor ingrowth through the stent mesh is common in uncovered SEMS and requires placement of another stent in an in-stent method. However, covered SEMS tends to be occluded by sludge, so it must be replaced because of the bacterial biofilm that forms on the covering membrane. The location of the biliary stricture (hilar or distal) should also be considered. Strategies for managing cholangitis as a result of occlusion by a biliary SEMS remain controversial, so prospective clinical trials are needed. © 2017 The Authors. Digestive Endoscopy © 2017 Japan Gastroenterological Endoscopy Society.

  11. A comparison of the temporary placement of 3 different self-expanding stents for the treatment of refractory benign esophageal strictures: a prospective multicentre study

    PubMed Central

    2012-01-01

    Background Refractory benign esophageal strictures (RBESs) have been treated with the temporary placement of different self-expanding stents with conflicting results. We compared the clinical effectiveness of 3 types of stents: self-expanding plastic stents (SEPSs), biodegradable stents, and fully covered self-expanding metal stents (FCSEMSs), for the treatment of RBES. Methods This study prospectively evaluated 3 groups of 30 consecutive patients with RBESs who underwent temporary placement of either SEPSs (12 weeks, n = 10), biodegradable stents (n = 10) or FCSEMSs (12 weeks, n = 10). Data were collected to analyze the technical success and clinical outcome of the stents as evaluated by recurrent dysphagia, complications and reinterventions. Results Stent implantation was technically successful in all patients. Migration occurred in 11 patients: 6 (60%) in the SEPS group, 2 (20%) in the biodegradable group and 3 (30%) in the FCSEMS group (P = 0.16). A total of 8/30 patients (26.6%) were dysphagia-free after the end of follow-up: 1 (10%) in the SEPS group, 3 (30%) in the biodegradable group and 4 (40%) in the FCSEMS group (P = 0.27). More reinterventions were required in the SEPS group (n = 24) than in the biodegradable group (n = 13) or the FCSEMS group (n = 13) (P = 0.24). Multivariate analysis showed that stricture length was significantly associated with higher recurrence rates after temporary stent placement (HR = 1.37; 95% CI = 1.08-1.75; P = 0.011). Conclusions Temporary placement of a biodegradable stent or of a FCSEMS in patients with RBES may lead to long-term relief of dysphagia in 30 and 40% of patients, respectively. The use of SEPSs seems least preferable, as they are associated with frequent stent migration, more reinterventions and few cases of long-term improvement. Additionally, longer strictures were associated with a higher risk of recurrence. PMID:22691296

  12. Influence of K-ras status and anti-tumour treatments on complications due to colorectal self-expandable metallic stents: a retrospective multicentre study.

    PubMed

    Fuccio, Lorenzo; Correale, Loredana; Arezzo, Alberto; Repici, Alessandro; Manes, Gianpiero; Trovato, Cristina; Mangiavillano, Benedetto; Manno, Mauro; Cortelezzi, Claudio Camillo; Dinelli, Marco; Cennamo, Vincenzo; de Bellis, Mario

    2014-06-01

    This study aimed to explore the relationship between K-ras status, anti-tumour treatments, and the complications of colorectal self-expandable metallic stenting in colorectal cancer. This is a retrospective, multicentre study of 91 patients with obstructive advanced colorectal cancer palliated with enteral stents between 2007 and 2011. K-ras wild-type tumours were diagnosed in 44 patients (48.4%); 82 (90.1%) received chemotherapy and 45 (49.4%) had additional biological therapy (34 bevacizumab, 11 cetuximab). Twenty-one (23.1%) experienced stent-related complications: 11 (52.4%) occurred in the K-ras mutant group (P=0.9). K-ras wild-type patients were not less likely to develop adverse events than K-ras mutant patients (OR, 0.99; 95% CI: 0.4-2.7). Overall mean time to complication was 167.6 days (range 4-720 days), with no difference between the two groups (141 vs. 197 days; P=0.5). Chemotherapy did not influence the risk of complications (OR, 0.56; 95% CI: 0.14-2.9), and there was no evidence that patients treated with chemotherapy and cetuximab were more likely to experience stent-related complications than patients treated with chemotherapy alone, or untreated (OR, 1.2; 95% CI: 0.2-5.9). Although perforation rates were higher with bevacizumab-based treatment (11.8% vs. 7%), this result was not statistically significant (P=0.69). K-ras mutation status, chemotherapy, and biological treatments should not influence colorectal stent-related complication rates. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  13. Temporary placement of covered self-expandable metallic stents in the management of benign biliary strictures.

    PubMed

    Yasuda, Ichiro; Mukai, Tsuyoshi; Doi, Shinpei; Tomita, Eiichi; Moriwaki, Hisataka

    2012-05-01

    Currently, endoscopic intervention is widely attempted as the first-line treatment of benign biliary strictures because of its convenience and low morbidity. Plastic tube stents (PS) are usually used for such treatment; however, covered self-expandable metallic stents (C-SEMS) are becoming more commonly used at some institutions. The temporary placement of C-SEMS may lead to better outcomes because of their larger diameter and, therefore, better dilation of the stricture, especially in refractory cases. The aim of the present study was to evaluate the efficacy of the temporary placement of C-SEMS in the management of benign biliary strictures. We retrospectively reviewed our endoscopic retrograde cholangiopancreatography (ERCP) database (May 1996 to December 2010), and extracted the data of patients who underwent endoscopic treatment for benign biliary strictures. Then, the follow-up data from patient charts were reviewed to determine the long-term outcomes of those procedures. All patients (n = 56) initially had a PS placed, with or without balloon dilation. However, C-SEMS placement was later attempted in 12 patients because the stricture was refractory to placement of the PS. During their follow-up periods, two patients died of unrelated diseases after 15 and 17 months, and another two still had the C-SEMS in place after 9 and 50 months. In the remaining eight patients, the C-SEMS was removed after a median placement period of 6 months (range, 2-15). Seven patients in this group have not experienced a recurrence at a median follow-up time of 48 months. However, in one patient, stenosis did recur 8 months after the C-SEMS was removed. Temporary placement of C-SEMS can be a treatment option for benign biliary strictures, especially in refractory cases. © 2012 The Authors. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

  14. Single-step simultaneous side-by-side placement of a self-expandable metallic stent with a 6-Fr delivery system for unresectable malignant hilar biliary obstruction: a feasibility study.

    PubMed

    Kawakubo, Kazumichi; Kawakami, Hiroshi; Kuwatani, Masaki; Kudo, Taiki; Abe, Yoko; Kawahata, Shuhei; Kubo, Kimitoshi; Kubota, Yoshimasa; Sakamoto, Naoya

    2015-02-01

    Bilateral self-expandable metallic stent (SEMS) placement for the management of unresectable malignant hilar biliary obstruction (UMHBO) is technically challenging to perform using the existing metallic stents with thick delivery systems. The recently developed 6-Fr delivery systems could facilitate a single-step simultaneous side-by-side placement through the accessory channel of the duodenoscope. The aim of this study was to evaluate the feasibility of this procedure. Between May and September 2013, 13 consecutive patients with UMHBO underwent a single-step simultaneous side-by-side placement of SEMS with the 6-Fr delivery system. The technical success rate, stent patency, and rate of complications were evaluated from the prospectively collected database. Technical success was achieved in 11 (84.6%, 95% confidence interval [CI]: 57.8-95.8) patients. The median procedure time was 25 min. Early and late complications were observed in 23% (one segmental cholangitis and two liver abscesses) and 15% (one segmental cholangitis and one cholecystitis) patients, respectively. Median dysfunction free patency was 263 days (95% CI: 37-263). Five patients (38%) experienced stent occlusion that was successfully managed by endoscopic stent placement. A single-step simultaneous side-by-side placement of SEMS with a 6-Fr delivery system was feasible for the management of UMHBO. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  15. Polyflex self-expanding, removable plastic stents: assessment of treatment efficacy and safety in a variety of benign and malignant conditions of the esophagus.

    PubMed

    Karbowski, M; Schembre, D; Kozarek, R; Ayub, K; Low, D

    2008-05-01

    Historically, esophageal fistulas, perforations, and benign and malignant strictures have been managed surgically or with the placement of permanent endoprostheses or metallic stents. Recently, a removable, self-expanding, plastic stent has become available. The authors investigated the use of this new stent at their institution. The study reviewed all the patients who received a Polyflex stent for an esophageal indication at the authors' institution between January 2004 and October 2006. Duration of placement, complications, and treatment efficacy were recorded. A total of 37 stents were placed in 30 patients (14 women and 16 men) with a mean age of 68 years (range, 28-92 years). Stent placement included 7 for fistulas, 3 for perforations, 1 for an anastomotic leak, 7 for malignant strictures, and 19 for benign strictures (8 anastomotic, 1 caustic, 5 reflux, 2 radiation, and 2 autoimmune esophagitis strictures, and 1 post-Nissen gas bloat stricture). The mean follow-up period was 6 months. Stent deployment was successful for all the patients, and no complications resulted from stent placement or removal. Nine stents migrated spontaneously. Three of three perforations and three of five fistulas sealed. Only one stent was removed because of patient discomfort. One patient with a radiation stricture experienced tracheoesophageal fistulas secondary to pressure necrosis. Of 20 patients with stricture, 18 experienced improvement in their dysphagia. Self-expanding, removable plastic stents are easily and safely placed and removed from the esophagus. This has facilitated their use in the authors' institution for an increasing number of esophageal conditions. Further studies to help define their ultimate role in benign and malignant esophageal pathology are warranted.

  16. The insertion of self expanding metal stents with flexible bronchoscopy under sedation for malignant tracheobronchial stenosis: a single-center retrospective analysis.

    PubMed

    McGrath, Emmet E; Warriner, David; Anderson, Paul

    2012-02-01

    To describe a 10-year experience of inserting Ultraflex™ self-expanding metal stents (SEMS) under sedation using flexible bronchoscopy for the treatment of malignant tracheobronchial stenosis in a tertiary referral centre. Medical notes were retrospectively reviewed for all patients who underwent SEMS insertion between 1999 and 2009. A data analysis of 68 patients who had Ultraflex™ SEMS inserted under sedation was completed. Thirty three males and 35 females with a mean age of 67.9 years (range 35-94) presented with features including dyspnea/respiratory distress (39 patients), stridor (16 patients) and hemoptysis/dyspnea (13 patients). Etiology of stenosis included lung cancer (46 patients) esophageal cancer (14 patients) and other malignancies (8 patients). Mean dose of midazolam administered was 5mg (range 0-10mg). The trachea was the most common site of stent insertion followed by the right and left main bronchus, respectively. Adjuvant laser therapy was applied at some stage in 31% of all cases, and chemotherapy and/or radiotherapy was administered to at least 64% of patients with malignant disease. Hemoptysis and stent migration were the most frequent complications (5 and 4 patients, respectively). The mean survival time of stented non-small cell lung cancer (NSCLC) patients was 214 days (range 5-1233) and that of esophageal malignancy was 70 days (range 12-249). Mean pack-year history of individuals with lung cancer requiring stent insertion was 37 (range 2-100). Ultraflex stents offer a safe and effective therapy for patients who are inoperable or unresectable that otherwise would have no alternative therapy. It has an immediate beneficial effect upon patients, not only through symptom relief but, in some, through prolongation of life. Survival data is no worse than other studies using different varieties of stents and insertion techniques indicating its longer-term efficacy. Moreover, this report highlights the feasibility of performing this procedure

  17. Polyflex expandable stents in the treatment of esophageal disease: initial experience.

    PubMed

    Pennathur, Arjun; Chang, Andrew C; McGrath, Kevin M; Steiner, Gregory; Alvelo-Rivera, Miguel; Awais, Omar; Gooding, William E; Christie, Neil A; Gilbert, Sebastien; Landreneau, Rodney J; Luketich, James D

    2008-06-01

    The new generation of expandable plastic esophageal stents (Polyflex; Boston Scientific, Natick, MA), combine the features of plastic and self-expanding metallic stents. The main objective of this study is to evaluate our initial experience with Polyflex expandable stents in the treatment of esophageal disease from two institutions. A total of 58 Polyflex stents were placed in 38 patients over a two-year period. There were 24 men and 14 women, with a median age of 63 years (range, 25 to 83). The most common indication for placement was an esophageal stricture in 25 patients (66%); other causes included leak in 8 (21%) and tracheoesophageal fistula (TEF) in 5 (13%). We evaluated the hospital course, complications, and outcomes. The median postoperative stay was one day. Complications included migration in 38 stents (63%) (28 patients; 73%), retrosternal chest discomfort in nine, reflux in four, airway obstruction in one, and food impaction in three. Continued leak or a persistent TEF occurred in five patients (38%). Reintervention was required predominantly due to migration of the stent at a mean interval of 46 days (range, 1 to 353). Patients with dysphagia improved significantly with dysphagia scores (1 = no dysphagia; 5 = unable to swallow saliva) improving from 3.44 to 2.15 (p < 0.0001). Polyflex stents were effective in the relief of dysphagia due to strictures. They were less effective in esophageal perforations or leaks. Their primary disadvantage is a high migration rate and further improvements in design are required to decrease this high incidence of migration.

  18. Feasibility and safety of placement of a newly designed, fully covered self-expandable metal stent for refractory benign pancreatic ductal strictures: a pilot study (with video).

    PubMed

    Park, Do Hyun; Kim, Myung-Hwan; Moon, Sung-Hoon; Lee, Sang Soo; Seo, Dong-Wan; Lee, Sung-Koo

    2008-12-01

    Painful chronic pancreatitis with main pancreatic ductal strictures is usually managed with endotherapy with a plastic stent. To date, the role of placement of metallic stents, especially uncovered ones in benign pancreatic ductal stricture, has been unsatisfactory as a result of stent dysfunction related to mucosal hyperplasia. We explored the feasibility and safety of temporary placement of a newly designed, fully covered self-expandable metal stent (FCSEMS) in painful chronic pancreatitis and refractory benign pancreatic ductal strictures. A prospective pilot and feasibility study. A tertiary academic center. Thirteen patients with chronic painful pancreatitis of alcoholic (8) or idiopathic (5) etiology. ERCP with temporary FCSEMS placement (2 months). Endoscopic removal of FCSEMSs was performed with a snare or rat-tooth forceps. End points were feasibility, safety, and morbidity. Successful FCSEMS placement was performed in all enrolled patients. After immediate placement of FCSEMS, 2 patients had mild acute pancreatitis related mainly to the stricture dilation procedure (Soehendra stent retriever or balloon dilation). Complications associated with stent placement included 5 migrations (39%, 1 proximal and 4 distal) and 2 incidents of cholestatic liver dysfunction associated with the compression of the bile duct orifice by expansion of FCSEMSs. In 1 patient with proximal migration, the stent was repositioned by an inflated retrieval balloon. Additional endoscopic biliary sphincterotomy with or without biliary stenting was performed in 2 patients with cholestatic liver dysfunction. There was no occurrence of pancreatic sepsis among any patients. FCSEMSs were removed from 9 of 9 patients without stent migration (100% [9/9] as per protocol, and 69% [9/13] as intention to treat, respectively). Improvement or resolution of the pancreatic ductal strictures was confirmed in all 13 patients on follow-up ERCP (2 months after stent placement), regardless of stent

  19. Unique usage of a partially covered metal stent for drainage of a pancreatic pseudocyst via endosonography-guided transcystgastrostomy.

    PubMed

    Nici, Anthony J; Hussain, Syed A; Kim, Sang H; Mehta, Preeti

    2012-05-01

    Pancreatic pseudocysts are frequent complications of pancreatitis episodes. The current therapeutic modalities for drainage of pancreatic pseudocysts include surgical, percutaneous, and endoscopic drainage modalities. Endosonography-assisted endoscopic drainage of these pseudocysts with the placement of multiple plastic or fully covered self-expanding biliary metal stents is becoming more commonly carried out. The present case report discusses the unique and successful drainage of a pancreatic pseudocyst with the placement of a partially covered self-expanding metal stent. © 2012 The Authors. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

  20. [Expandable stents and composite prosthesis].

    PubMed

    Baldeyrou, P

    1999-11-01

    Today, numerous expandable and mixed silicone metallic stents for trachea and bronchi are available. Among the many technical propositions, Nitinol is a new alloy with promising potential, offering the advantage of shape memory. The right stent is the one which best meets the needs of the individual stenotic situation as evaluated by endoscopy and CT. Sufficient experience has been acquired only with the Dumon stent, giving exact information about its qualities and possible complications. The new stents are thinner. Some can be inserted under fluoroscopic and fibroscopic control. They are presumed to produce fewer complications an provide answers to some still unresolved questions such as dyskinesia or stenosis on short bronchi. They appear to be more easily inserted on the tracheo-bronchial tree. More experience is needed to satisfactorily identify specific indications and contraindications. A prospective registry will be important to obtain comparative information more quickly.

  1. Treatment of complex airway lesions after lung transplantation with self-expandable nitinol stents: early experience.

    PubMed

    Anile, M; Venuta, F; Diso, D; Liparulo, V; Ricella, C; De Giacomo, T; Pugliese, F; Rolla, M; Quattrucci, S; Pecoraro, Y; Rendina, E A; Coloni, G F

    2010-05-01

    Airway complications (AC) are considered a serious cause of morbidity after lung transplantation (LT). Mechanical dilatation, laser vaporization, and silicone stent placement usually solve it. However, the use of self-expandable metallic stents (SENS) may be indicated in selected cases. Ten lung transplant recipients with AC were treated with SENS. Six patients underwent LT for cystic fibrosis, 2 for idiopathic pulmonary fibrosis, 1 for bronchiectasis, and 1 for emphysema. All patients received at least 1 treatment attempt with dilatation and silicone stent placement. The indications for SENS placement were the presence of a tortuous airway axis with stenosis and malacia of the right main bronchus in 5 patients; a long stenosis of the main and intermediate right bronchus involving the upper lobe orifice in 3 patients; or malacia that could not be stabilized with silicone stents in 3 cases. In 1 patient the procedure was bilateral. Functional improvement was immediate with a mean forced expiratory volume at 1 second (FEV(1)) gain of 35%. No stent dislocation was observed. Symptoms did not occur again in 5 patients with previous recurrent episodes of pneumonia. One stenosis, which was due to the ingrowth of granulation tissue occurred at 6 months after the procedure, was successfully treated with mechanical dilatation and laser vaporization. The deployment of SENS in a selected group of patients with AC after LT was easy, safe, and effective. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  2. Fluoroscopic removal of retrievable self-expandable metal stents in patients with malignant oesophageal strictures: Experience with a non-endoscopic removal system.

    PubMed

    Kim, Pyeong Hwa; Song, Ho-Young; Park, Jung-Hoon; Zhou, Wei-Zhong; Na, Han Kyu; Cho, Young Chul; Jun, Eun Jung; Kim, Jun Ki; Kim, Guk Bae

    2017-03-01

    To evaluate clinical outcomes of fluoroscopic removal of retrievable self-expandable metal stents (SEMSs) for malignant oesophageal strictures, to compare clinical outcomes of three different removal techniques, and to identify predictive factors of successful removal by the standard technique (primary technical success). A total of 137 stents were removed from 128 patients with malignant oesophageal strictures. Primary overall technical success and removal-related complications were evaluated. Logistic regression models were constructed to identify predictive factors of primary technical success. Primary technical success rate was 78.8 % (108/137). Complications occurred in six (4.4 %) cases. Stent location in the upper oesophagus (P=0.004), stricture length over 8 cm (P=0.030), and proximal granulation tissue (P<0.001) were negative predictive factors of primary technical success. If granulation tissue was present at the proximal end, eversion technique was more frequently required (P=0.002). Fluoroscopic removal of retrievable SEMSs for malignant oesophageal strictures using three different removal techniques appeared to be safe and easy. The standard technique is safe and effective in the majority of patients. The presence of proximal granulation tissue, stent location in the upper oesophagus, and stricture length over 8 cm were negative predictive factors for primary technical success by standard extraction and may require a modified removal technique. • Fluoroscopic retrievable SEMS removal is safe and effective. • Standard removal technique by traction is effective in the majority of patients. • Three negative predictive factors of primary technical success were identified. • Caution should be exercised during the removal in those situations. • Eversion technique is effective in cases of proximal granulation tissue.

  3. Efficacy of self-expandable metal stents in management of benign biliary strictures and comparison with multiple plastic stents: a meta-analysis.

    PubMed

    Khan, Muhammad Ali; Baron, Todd H; Kamal, Faisal; Ali, Bilal; Nollan, Richard; Ismail, Mohammad Kashif; Tombazzi, Claudio; Artifon, Everson L A; Repici, Alessandro; Khashab, Mouen A

    2017-07-01

    Background and study aims  There is burgeoning interest in the utilization of covered self-expandable metal stents (CSEMSs) for managing benign biliary stricture (BBS). This systematic review and meta-analysis evaluated cumulative stricture resolution and recurrence rates using CSEMSs and compared performance of CSEMSs and multiple plastic stents (MPS) in BBS management. Method  Searches in several databases identified studies including ≥ 10 patients that utilized CSEMSs for BBS treatment. Weighted pooled rates were calculated for stricture resolution and recurrence. Pooled risk ratios (RRs) comparing CSEMSs with MPS were calculated for stricture resolution, stricture recurrence, and adverse events. Pooled difference in means was calculated to compare number of endoscopic retrograde cholangiopancreatographies (ERCPs) in each group.  Results  The meta-analysis included 22 studies with 1298 patients. Weighted pooled rate for BBS resolution with CSEMS was 83 % (95 % confidence limits [95 %CLs] 78 %, 87 %; I 2  = 72 %). On meta-regression analysis, resolution in chronic pancreatitis patients and post-orthotopic liver transplant patients were significant predictors of heterogeneity. Weighted pooled rate for stricture recurrence with CSEMSs was 16 % (11 %, 22 %). Overall rate of adverse events requiring intervention and/or hospitalization was 15 %. Four randomized controlled trials with 213 patients compared CSEMSs with MPS: the pooled RRs for stricture resolution, recurrence, and adverse events were 1.07 (0.97, 1.18), 0.88 (0.48, 1.63), and 1.16 (0.71, 1.88), respectively with no heterogeneity. Pooled difference in means for number of ERCPs was - 1.71 ( - 2.33, - 1.09) in favor of CSEMS. Conclusions  CSEMSs appear to have excellent efficacy in BBS management. They are as effective as MPS but require fewer ERCPs to achieve clinical success. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Self-expandable Metallic Stents Contribute to Reducing Perioperative Complications in Colorectal Cancer Patients with Acute Obstruction.

    PubMed

    Furuke, Hirotaka; Komatsu, Shuhei; Ikeda, Jun; Tanaka, Sachie; Kumano, Tatsuya; Imura, Ken-Ichiro; Shimomura, Katsumi; Taniguchi, Fumihiro; Ueshima, Yasuo; Takashina, Ken-Ichiro; Lee, Chol Joo; Deguchi, Eiichi; Ikeda, Eito; Otsuji, Eigo; Shioaki, Yasuhiro

    2018-03-01

    The self-expandable metallic stent (SEMS) is an excellent non-invasive tool for emergent bowel obstruction. This study was designed to evaluate the clinical usefulness of the SEMS for avoiding perioperative complications. We analyzed a total of 47 consecutive patients who had a bowel obstruction due to colorectal cancer at initial diagnosis between 2012 and 2017 from hospital records. Perioperative complications occurred in 30% (14/47) of patients. Univariate and multivariate logistic regression analyses identified an age of more than 75 years [p=0.037, OR=6.84 (95% CI=1.11-41.6)] and the absence of an SEMS treatment [p=0.028, OR=18.5 (95% CI=1.36-250.0)] as independent risk factors for perioperative complications. Pneumonia (12.7% (6/47)) was the most common complication. There were no pneumonia patients (0% (0/15)) who were treated with the SEMS. In contrast to patients with the non-SEMS treatment, 18.7% (6/32) of all patients and 35.7% (5/14) of elderly patients had pneumonia. The SEMS is a safe and effective treatment for avoiding perioperative complications, particularly pneumonia, and may be a crucial strategy in elderly patients with acute obstruction due to colorectal cancer. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  5. Pneumoperitoneum Caused by Transhepatic Air Leak After Metallic Biliary Stent Placement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, Jei Hee; Lee, Deok Hee; Yu, Jeong-Sik

    2000-11-15

    A self-expanding metallic biliary stent was placed for palliation of a common bile duct obstruction in a 68-year-old male with unresectable pancreatic head cancer 3 days after initial percutaneous right transhepatic catheter decompression. The stent crossed the ampulla of Vater. Three days later, the stent was balloon-dilated and the percutaneous access was removed. At removal, a small contrast leak from the transhepatic tract was seen. Three days later, pneumoperitoneum was found with symptoms of peritoneal irritation and fever. A widely open sphincter of Oddi caused by the metallic stent, accompanied by delayed sealing of the transhepatic tract, may have causedmore » the air and bile leakage into the peritoneal space. This case shows that pneumoperitoneum may occur without ductal tear or bowel injury, with a biliary stent crossing the ampulla of Vater.« less

  6. Transapical Aortic Valve Replacement under Real-time Magnetic Resonance Imaging Guidance: Experimental Results with Balloon-Expandable and Self-Expanding Stents

    PubMed Central

    Horvath, Keith A.; Mazilu, Dumitru; Kocaturk, Ozgur; Li, Ming

    2010-01-01

    Objective Aortic valves have been implanted on self-expanding (SE) and balloon-expandable (BE) stents minimally invasively. We have demonstrated the advantages of transapical aortic valve implantation (tAVI) under real-time magnetic resonance imaging (rtMRI) guidance. Whether there are different advantages to SE or BE stents is unknown. We report rtMRI guided tAVI in a porcine model using both SE and BE stents, and compare the differences between the stents. Methods Twenty-two Yucatan pigs (45-57kgs.) underwent tAVI. Commercially available stentless bioprostheses (21-25mm) were mounted on either BE platinum-iridium stents or SE nitinol stents. rtMRI guidance was employed as the intraoperative imaging. Markers on both types of stents were used to enhance the visualization in rtMRI. Pigs were allowed to survive and had follow-up MRI scans and echocardiography at 1, 3 and 6 months postoperatively. Results rtMRI provided excellent visualization of the aortic valve implantation mounted on both stent types. The implantation times were shorter with the SE stents (60±14 seconds) than BE (74±18s), (p=0.027). Total procedure time was 31 and 37 minutes respectively (p=0.12). It was considerably easier to manipulate the SE stent during deployment without hemodynamic compromise. This was not always the case with the BE stent and its placement occasionally resulted in coronary obstruction and death. Long-term results demonstrated stability of the implants with preservation of myocardial perfusion and function over time for both stents. Conclusions SE stents were easier to position and deploy thus leading to fewer complications during tAVI. Future optimization of SE stent design should improve clinical results. PMID:20971017

  7. Multi-stage surgery for airway patency after metallic stent removal in benign laryngotracheal airway disease in two adolescents.

    PubMed

    Coordes, Annekatrin; Todt, Ingo; Ernst, Arne; Seidl, Rainer O

    2013-05-01

    Laryngotracheal stents may damage the highly complex laryngeal structures, impair voice and swallowing functions and cause tissue ingrowths, thereby necessitating airway patency interventions. In benign airway disease, the number of adolescents with laryngotracheal stents is therefore limited. We present two cases of laryngeal metallic stent placement following benign airway disease. Two adolescents presented with severe dyspnea and self-expandable metallic stent placement after benign laryngotracheal stenoses. Granulation tissue ingrowths required additional surgical interventions every 6-8 weeks to recanalize the stent lumen. We performed multi-stage surgery including removal of the embedded stent, segmental resection of the stenotic area, end-to-end-anastomosis and laryngotracheal reconstruction respectively, to achieve patent airway without tracheal cannulation. Montgomery T-tubes were temporarily inserted to bridge the complex reconstructions. In both adolescents, we achieved successful removal of the embedded stent and patent airway. Bilateral vocal fold paralysis required additional surgery to improve the final airway patency and vocal rehabilitation. Stent removal, segmental resection and laryngotracheal reconstruction provide the achievement of patent airway and allow decannulation. Temporary Montgomery T-tubes bridge complex laryngotracheal reconstructions. In benign laryngeal airway disease, stent placement should be avoided, especially in adolescents. Transfer to a specialist center should be considered prior to metallic stent implantation. In general, self-expanding tracheobronchial stents can be placed in selected patients where surgical interventions are limited. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. Partial stent-in-stent placement of biliary metallic stents using a short double-balloon enteroscopy.

    PubMed

    Tsutsumi, Koichiro; Kato, Hironari; Tomoda, Takeshi; Matsumoto, Kazuyuki; Sakakihara, Ichiro; Yamamoto, Naoki; Noma, Yasuhiro; Sonoyama, Takayuki; Okada, Hiroyuki; Yamamoto, Kazuhide

    2012-12-07

    Endoscopic intervention is less invasive than percutaneous or surgical approaches and should be considered the primary drainage procedure in most cases with obstructive jaundice. Recently, therapeutic endoscopic retrograde cholangiopancreatography (ERCP) using double-balloon enteroscopy (DBE) has been shown to be feasible and effective, even in patients with surgically altered anatomies. On the other hand, endoscopic partial stent-in-stent (PSIS) placement of self-expandable metallic stents (SEMSs) for malignant hilar biliary obstruction in conventional ERCP has also been shown to be feasible, safe and effective. We performed PSIS placement of SEMSs for malignant hilar biliary obstruction due to liver metastasis using a short DBE in a patient with Roux-en-Y anastomosis and achieved technical and clinical success. This procedure can result in quick relief from obstructive jaundice in a single session and with short-term hospitalization, even in patients with surgically altered anatomies.

  9. Mechanical properties of different airway stents.

    PubMed

    Ratnovsky, Anat; Regev, Noa; Wald, Shaily; Kramer, Mordechai; Naftali, Sara

    2015-04-01

    Airway stents improve pulmonary function and quality of life in patients suffering from airway obstruction. The aim of this study was to compare main types of stents (silicone, balloon-dilated metal, self-expanding metal, and covered self-expanding metal) in terms of their mechanical properties and the radial forces they exert on the trachea. Mechanical measurements were carried out using a force gauge and specially designed adaptors fabricated in our lab. Numerical simulations were performed for eight different stent geometries, inserted into trachea models. The results show a clear correlation between stent diameter (oversizing) and the levels of stress it exerts on the trachea. Compared with uncovered metal stents, metal stents that are covered with less stiff material exert significantly less stress on the trachea while still maintaining strong contact with it. The use of such stents may reduce formation of mucosa necrosis and fistulas while still preventing stent migration. Silicone stents produce the lowest levels of stress, which may be due to weak contact between the stent and the trachea and can explain their propensity for migration. Unexpectedly, stents made of the same materials exerted different stresses due to differences in their structure. Stenosis significantly increases stress levels in all stents. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  10. Predictors of Complications and Mortality in Patients with Self-Expanding Metallic Stents for the Palliation of Malignant Colonic Obstruction

    PubMed Central

    Sousa, Mafalda; Pinho, Rolando; Proença, Luísa; Silva, Joana; Ponte, Ana; Rodrigues, Jaime; Carvalho, João

    2017-01-01

    Introduction Self-expanding metallic stents (SEMS) for palliative purposes in malignant colonic obstruction are an alternative to surgery that has gained popularity over time. Methods We performed a retrospective study of patients submitted to SEMS for palliation of obstructing malignant colorectal cancer from 2005 to 2015 to evaluate predictive clinical factors for complications and mortality. Results Forty-five patients with high rates of technical and clinical success were included (97.8 and 95.6%, respectively), with complications occurring in 17.8% (8.9% perforations, 4.4% obstructions, and 4.4% migrations). The length of the stenosis was superior in patients with complications (p = 0.01); 11.1% of patients had a re-intervention (2.2% surgery and 8.9% placement of another SEMS). Relief of obstruction without intervention was maintained until death in 77.8% of patients and in 81.4% of patients who had immediate clinical success. The mortality rate was 37.2% at 30 days, 56.5% at 60 days, and 87.5% at 1 year. There were no predictors of survival identified, including age, sex, tumor stage, metastasis, or complications of the procedure. Discussion and Conclusions In this study, SEMS placement was associated with a high rate of technical and clinical success and a low rate of complications, being an option to palliate patients with obstructive neoplasia. The length of the stenosis was associated with a greater risk of complications. The majority of stent-related complications can be managed successfully without surgery. PMID:28848796

  11. Food impaction after expandable metal stent placement: experience in 1,360 patients with esophageal and upper gastrointestinal tract obstruction.

    PubMed

    Song, Min; Song, Ho-Young; Kim, Jin Hyoung; Park, Jung-Hoon; Jung, Hwoon-Yong; Kim, Jong-Hoon; Kim, Sung-Bae

    2011-09-01

    To retrospectively evaluate the incidence, predictive factors, and interventional management of food impaction after expandable metallic stent placement in patients with obstruction of the esophagus or upper gastrointestinal tract caused by benign or malignant disease. Between March 1993 and March 2010, 1,360 patients (1,029 men, 331 women; age range, 21-89 y; mean age, 61 y) underwent fluoroscopically guided stent placement for dysphagia caused by esophageal or gastrointestinal tract strictures. Five types of covered expandable metal stents were used, including four types of esophageal stents (types A-D) and one type of gastroduodenal stent (type E), with types A, B, C, D, and E stents used in 180, 60, 90, 432, and 598 patients, respectively. Multivariate analysis was performed to evaluate factors predictive of food impaction. Food impaction occurred in 41 of 1,360 patients (3.0%). The food impaction rates for types A, B, C, D, and E stents were 0.6%, 1.7%, 1.1%, 3.2%, and 4.0%, respectively. Multivariate analysis showed that stent length was an independent predictor of food impaction (odds ratio, 0.839; P = .012). Of the 41 patients with food impaction, 23 underwent endoscopic management, 12 underwent fluoroscopically guided management, and six did not require management because impacted food spontaneously passed through the stent. The overall food impaction rate was 3.0%, with multiple logistic regression analysis showing that shorter stent length was the only significant predictor of food impaction. Food impaction can be managed by endoscopic or fluoroscopically guided removal or placement of a second stent. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

  12. Performance of a self-expanding silicone stent in palliation of benign airway conditions.

    PubMed

    Gildea, Thomas R; Murthy, Sudish C; Sahoo, Debashish; Mason, David P; Mehta, Atul C

    2006-11-01

    The Polyflex stent (Boston Scientific; Boston, MA) is a self-expanding, thin-walled, silicone stent. Its use has been described in the management of patients with malignant airway obstruction, yet reports of its use for treatment of benign airway conditions are rare. We report a retrospective review of our experience with the Polyflex stent in the management of benign airway conditions. A total of 16 stents were deployed in 12 patients. The indications for the stent placement included the following: anastomotic stenosis following lung transplantation (LTR) [four patients]; tracheal stenosis (three patients); tracheobronchomalacia (two patients); tracheobronchopathiaosteochondroplastica (one patient); relapsing polychondritis (one patient); and bronchopleural fistula (one patient). Even though immediate palliation was established in most cases (90%), the incidence of complications was 75%. Stent migration was the most common consequence, with time to the event ranging from < 24 h to 7 months. One stent was expectorated within < 24 h. One patient coughed up a portion of the inner lining of the stent 7 months after its placement. Emergent bronchoscopy was required in four patients for mucous impaction. The complication rate was 100% in patients with LTR-related anastomotic stenosis. The use of the Polyflex stent for the treatment of benign airway conditions is associated with a high complication rate. We have abandoned its use under such conditions in our practice.

  13. An intriguing design concept to enhance the pulsatile fatigue life of self-expanding stents.

    PubMed

    Hsiao, Hao-Ming; Yin, Ming-Ting

    2014-02-01

    Intravascular stenting has emerged as the primary treatment for vascular diseases and has received great attention from the medical community since its introduction two decades ago. The endovascular self-expanding stent is used to treat peripheral artery diseases; however, once implanted, these stents suffer from various cyclic motions caused by pulsatile blood pressure and daily activities. Due to this challenging environment, fatigue performance has become a critical issue for stent design. In this paper, a simple yet intriguing concept of stent design aimed at enhancing pulsatile fatigue life is investigated. The concept of this design is to shift the highly concentrated stresses/strains away from the crown and re-distribute them along the stress-free bar arm by tapering its strut width. Finite element models were developed to evaluate the mechanical integrity and pulsatile fatigue resistance of the stent to various loading conditions. Results show that the fatigue safety factor jumped to 2.5-3.0 times that of the standard stent with constant strut width. This is astonishing considering that the stent profile and scaffolding were not compromised. The findings of this paper provide an excellent approach to the optimization of future stent design to greatly improve stent fatigue performance.

  14. A prospective randomized study for efficacy of an uncovered double bare metal stent compared to a single bare metal stent in malignant biliary obstruction.

    PubMed

    Lee, Hyun Jik; Chung, Moon Jae; Park, Jeong Yup; Park, Seung Woo; Nam, Chung Mo; Song, Si Young; Bang, Seungmin

    2017-08-01

    A biliary self-expandable metal stent (SEMS) is commonly used to relieve malignant biliary obstruction. The aim of this study was to compare the efficacy of a conventional uncovered SEMS with that of a newly developed uncovered double bare metal stent in reducing the risk of stent occlusion caused by tumor ingrowth. We performed a prospective, open-labeled, randomized trial in 71 patients at Severance Hospital, Yonsei University College of Medicine from June 2013 to June 2014. Patients with inoperable malignant biliary obstruction were included and randomized to receive an uncovered single bare metal stent (SBSs; S&G Biotech Inc.), an uncovered single bare metal stent (SBSt; Taewoong Medical), or an uncovered double bare metal stent (DBS; S&G Biotech Inc.). The mean age was 66.6 years (range, 35-83), and 42 (59.2%) were male. The mean duration of stent patency was 212 days (±152) in the DBS group (n = 24) compared with 124 days (±98) in the SBSs group (n = 23; P = 0.022 for noninferiority) and 116 days (±79) in the SBSt group (n = 24; P = 0.010 for noninferiority). There were no differences in the incidences of early and delayed complications or migration. The newly developed DBS is noninferior to the conventional uncovered SEMSs on duration of stent patency and tumor ingrowth occurred less frequently in the DBS group. This might decrease the need for reintervention and offer a better quality of life. The trial is registered with Clinicaltrials.gov no: NCT01869894.

  15. Endoscopic management of malignant biliary obstruction by means of covered metallic stents: primary stent placement vs. re-intervention.

    PubMed

    Kida, M; Miyazawa, S; Iwai, T; Ikeda, H; Takezawa, M; Kikuchi, H; Watanabe, M; Imaizumi, H; Koizumi, W

    2011-12-01

    Recent progress in chemotherapy has prolonged the survival of patients with malignant biliary strictures, leading to increased rates of stent occlusion. Occlusion of covered metallic stents now occurs in about half of all patients with malignant biliary strictures. The removal of metallic stents followed by placement of a second stent has been attempted, but outcomes remain controversial. The aim of the current study was to evaluate the effectiveness and safety of the primary placement and secondary placement (re-intervention) of covered metallic stents and to assess the feasibility and safety of stent removal. The study included 186 patients with unresectable malignant biliary strictures who underwent primary stent placement between October 2001 and March 2010.  Covered biliary self-expandable metal stents (SEMSs) were removed in 39 of these patients, and 36 underwent re-intervention. The patency times, occlusion rates of the first stent and re-intervention, success rates of stent removal, and complications were investigated. Covered SEMSs were placed in 186 patients. The median patency time of the first stent was 352 days. Stent occlusion occurred in 48.9 % of the patients and was mainly caused by debris or food residue (37 %), dislocation (19 %), and migration with hyperplasia (19 %). Stent removal was attempted in 50 patients and was successful without complication in 39 (78 %). Most of the patients in whom stent removal was unsuccessful had migration with hyperplasia. The median patency time of the second stent was 263 days. The stent patency time did not significantly differ between the first and the second stent. Covered SEMSs could be safely removed at the time of stent occlusion. Patency rates were similar for initial stent placement and re-intervention. © Georg Thieme Verlag KG Stuttgart · New York.

  16. Do expandable metallic airway stents have a role in the management of patients with benign tracheobronchial disease?

    PubMed

    Madden, Brendan P; Loke, Tuck-Kay; Sheth, Abhijat C

    2006-07-01

    With increasing availability many centers are deploying expandable metallic stents to manage patients with diverse endobronchial disorders. Although these devices have an important role in malignant disease their usefulness in benign large airway disorders is less defined. Between 1997 and 2005, 31 patients aged 34 to 83 years with benign large airway compromise secondary to tracheomalacia (n = 7), posttracheostomy stricture (n = 8), posttracheostomy rupture (n = 2), postpneumonectomy bronchopleural fistula (n = 2), stricture after lung transplantation (n = 3), lobectomy, tuberculosis, traumatic injury to right main bronchus (n = 1 patient each), and external compression of the airway secondary to achalasia, multinodular goiter, aortic aneurysm, right brachiocephalic artery aneurysm, right interrupted aortic arch, and dissecting aneurysm (n = 1 patient each) who were medically unfit for formal surgical intervention were treated by Ultraflex stent deployment. The range of follow-up was 1 week to 96 months. Stents were deployed under anesthesia using rigid bronchoscopy. Complications included granulation tissue formation (n = 11) treated with Nd: YAG laser ablation, stent migration (n = 1; stent removed, another deployed), metal fatigue (n = 1), stent removal (n = 1), mucus plugging (n = 2), and halitosis (n = 6) difficult to treat despite antibiotics. Thirteen patients died of unrelated causes between 1 week and 15 months after stent deployment. Endobronchial metallic stents should be considered only for selected patients with large airway compromise secondary to benign airway diseases for whom other medical comorbidities contraindicate formal airway surgery. Once deployed, they are difficult to remove, are associated with significant complications, and require prospective bronchoscopic surveillance and often further therapeutic intervention.

  17. Endoscopic ultrasound staging is adversely affected by placement of a self-expandable metal stent: fact or fiction?

    PubMed

    Shami, Vanessa M; Mahajan, Anshu; Sundaram, Vinay; Davis, Eric M; Loch, Michelle M; Kahaleh, Michel

    2008-11-01

    Accurate preoperative staging of pancreatic cancer (Pca) is crucial to direct management. There is a perception that endoscopic ultrasound (EUS) staging should be performed before biliary decompression because of artifact caused by self-expandable metal stents (SEMS). Our aim is to determine whether placement of SEMS affects the staging of Pca. Fifty-five patients (35 men; mean age, 67 years) with newly diagnosed Pca staged in the last 5 years and captured prospectively were divided into 2 groups matched by age, sex, and final staging. The staging accuracy of EUS in patients who had a SEMS (n = 28) was compared with patients without a SEMS (n = 27). The gold standard was surgical pathology, or cytologic confirmation of metastatic disease. Multivariate analysis was effected on age, sex, presence of SEMS, and presence of metastasis to assess prediction of staging inaccuracy. Endoscopic ultrasound correctly staged 14 (52%) of 27 patients in the no-SEMS group and 13 (46%) of 28 in the SEMS group. Logistic regression analysis identified only metastasis as a predictor of inaccuracy in EUS staging. Endoscopic ultrasound staging of Pca does not seem to be affected by the presence of a SEMS. The major reason for misstaging in both groups was failure to detect metastatic disease.

  18. Evaluation of a Bioabsorbable Self-Expandable Vein Stent-Base Made of Poly(L-lactide) In Vitro and In Vivo.

    PubMed

    Løvdal, Alexandra Liv Vest; Calve, Sarah; Yang, Shuo; Van Alstine, William; Binkert, Christoph A; Klausen, Kasper

    2017-01-01

    This study was designed to evaluate performance and tissue response to a self-expandable bioabsorbable vein stent-base cut from a tube with enhanced stiffness and strength in vitro and in vivo. A diamond-shaped stent-base was cut from a sequential biaxially strained poly(L-lactide) (PLLA) tube for optimized performance. The performance of the stent-base was evaluated in a finite element analysis model, and validation was attempted in vitro through a cyclic flat-plate compression and radial force measurement. The performance of the stent-base was tested in vivo using 3 sheep with 2 implants each for 2 and 3½ weeks, respectively. In vitro the stent-base showed an elliptical deformation but no fractures. In vivo the stent-base showed adequate radial force and no migration. All implanted stent-bases showed multiple fractures not only at the predicted stress zones but at all connecting points. Fragments of the caudal stent-base stayed in the vein wall indicating sufficient tissue coverage to avoid embolization of the fractured stent pieces, whereas fragments from the cranial device remaining were few. Neointima formation was confirmed histologically at 2 and 3½ weeks. A bioabsorbable self-expandable stent-base made from PLLA for large veins seems feasible, but over time, the PLLA used in this study appears too stiff and lacks the sufficient flexibility to move with the vena cava, causing multiple fractures.

  19. Evaluation of a Bioabsorbable Self-Expandable Vein Stent-Base Made of Poly(l-lactide) In Vitro and In Vivo

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Løvdal, Alexandra Liv Vest, E-mail: alvlo@nanotech.dtu.dk; Calve, Sarah; Yang, Shuo

    PurposeThis study was designed to evaluate performance and tissue response to a self-expandable bioabsorbable vein stent-base cut from a tube with enhanced stiffness and strength in vitro and in vivo.MethodsA diamond-shaped stent-base was cut from a sequential biaxially strained poly(l-lactide) (PLLA) tube for optimized performance. The performance of the stent-base was evaluated in a finite element analysis model, and validation was attempted in vitro through a cyclic flat-plate compression and radial force measurement. The performance of the stent-base was tested in vivo using 3 sheep with 2 implants each for 2 and 3½ weeks, respectively.ResultsIn vitro the stent-base showed anmore » elliptical deformation but no fractures. In vivo the stent-base showed adequate radial force and no migration. All implanted stent-bases showed multiple fractures not only at the predicted stress zones but at all connecting points. Fragments of the caudal stent-base stayed in the vein wall indicating sufficient tissue coverage to avoid embolization of the fractured stent pieces, whereas fragments from the cranial device remaining were few. Neointima formation was confirmed histologically at 2 and 3½ weeks.ConclusionA bioabsorbable self-expandable stent-base made from PLLA for large veins seems feasible, but over time, the PLLA used in this study appears too stiff and lacks the sufficient flexibility to move with the vena cava, causing multiple fractures.« less

  20. Internal stenting in malignant biliary obstruction.

    PubMed

    Cowling, M G; Adam, A N

    2001-03-01

    Internal stenting in inoperable malignant biliary obstruction plays an important role in patient management. Surgical bypass may still be undertaken where there is also duodenal obstruction, though the need for gastroenterostomy may be reduced with the increasing use of metallic stents for the relief of malignant gastric outlet obstruction. Stents may be placed endoscopically or percutaneously, though in most centers the endoscopic route is usually tried first, with the percutaneous route being reserved for endoscopic failures. Plastic and self-expanding metallic biliary stents are available, each with its own advantages and disadvantages. In general, longer periods of patency are observed with metallic stents, though they are more expensive. Plastic stents can be changed endoscopically relatively easily when they have blocked, and in practice it is common for plastic stents to be inserted via this route for initial biliary drainage. If there is prolonged survival thereafter, many workers insert a metallic stent in an attempt to reduce the number of interventions required. If the percutaneous route is being employed, the histologic diagnosis has been confirmed, and the malignancy is inoperable, our practice is to use a self-expanding metallic stent, as the delivery system is relatively small and subsequent occlusion less likely.

  1. Treatment of gastric leaks with coated self-expanding stents after sleeve gastrectomy.

    PubMed

    Serra, Carlos; Baltasar, Aniceto; Andreo, Luis; Pérez, Nieves; Bou, Rafael; Bengochea, Marcelo; Chisbert, Juan José

    2007-07-01

    Duodenal switch (DS) is one of the most effective techniques for the treatment of morbid obesity and its co-morbidities, with mortality rate <1%, but with 9.4% morbidity rates (6.5% due to leaks). In our experience, leaks of the staple-line after sleeve gastrectomy (SG) are the most frequent sites of fistula formation and conservative treatment usually takes a long time. We present our experience in the treatment of gastric leaks with coated self-expandable stents (CSES). 6 patients had gastric leaks at the gastroesophageal (GE) junction after SG or DS. One patient had a symptomatic gastro-bronchial fistula. Stents were placed by the interventional radiologist under fluoroscopic control and removed endoscopically. In one case, we used an uncoated Wallstent. In two patients, percutaneous microcoil embolization of the fistula was added. The patient treated with the Wallstent required a total gastrectomy 6 months after placement of the uncovered stent. In the other 5 patients, coated stents were successfully removed and the gastric leaks completely sealed. CSES are proposed as an alternative therapeutic option for the management of GE junction leaks in bariatric surgery with good results in terms of morbidity and survival.

  2. [Expandable metal mesh stents for treatment of tracheal stenoses and tracheomalacia].

    PubMed

    Müller, C; Dienemann, H; Hoffmann, H; Berger, H; Storck, M; Jolk, A; Schildberg, F W

    1993-01-01

    The treatment of tracheo-bronchial stenosis or tracheomalacia is mainly carried out by means of resection or tracheoplastic operative strategies. Since the introduction of metal-mesh stents, a definitive endoluminal therapy has to be considered under new aspects. Six patients with malignant stenosis or tracheomalacia due to compression were treated by implantation of Palmaz- or Wallstents. Immediately after the implantation, patients were relieved from dyspnoea, the forced inspiratory volume-1 (FIV1) was normalized. All implanted stents were well tolerated, even in the long-time follow-up (19 months). Bronchoscopic control showed overgrowth of the metal meshes by respiratory epithelium. The implantation of metal-mesh stents is an adequate alternative in the treatment of malignant stenosis and tracheomalacia.

  3. Malignant esophageal-tracheobronchial strictures: parallel placement of covered retrievable expandable nitinol stents.

    PubMed

    Nam, D H; Shin, J H; Song, H Y; Jung, G S; Han, Y M

    2006-02-01

    To assess the safety and clinical effectiveness of the parallel placement of covered retrievable expandable metallic stents in the palliative treatment of malignant esophageal and tracheobronchial strictures. Under fluoroscopic guidance, parallel stents were placed in 12 symptomatic patients with both malignant esophageal and tracheobronchial strictures. Seven of these 12 patients also had an esophagorespiratory fistula (ERF) and one patient had an esophagocutaneous fistula. Technical success, clinical improvement, complications, and survival rates were evaluated. A total of 28 esophageal and airway stents were successfully placed. The grade of dysphagia and dyspnea score significantly decreased after stent placement (P=0.002 and 0.003, respectively). ERF and esophagocutaneous fistula were sealed off in all eight patients after esophageal stent placement; however, the esophagocutaneous fistula reopened 1 month later. Complications included stent migration or expectoration (n=3), tracheal compression by the esophageal stent (n=3), new fistula development due to covering membrane degradation of the esophageal stent (n=1), and symptomatic sputum retention (n=1). Stent removal was easily performed for two stents; one migrated stent and the other with covering membrane degradation. All 12 patients died within the mean survival period of 72.50 days (range 7-375 days). Parallel placement of covered retrievable expandable metallic stents is safe and effective for the palliative treatment of malignant esophageal and tracheobronchial strictures.

  4. A Novel Self-Expandable, Radioactive Airway Stent Loaded with 125I Seeds: A Feasibility and Safety Study in Healthy Beagle Dog.

    PubMed

    Wang, Yong; Guo, Jin-He; Zhu, Guang-Yu; Zhu, Hai-Dong; Chen, Li; Lu, Jian; Wang, Chao; Teng, Gao-Jun

    2017-07-01

    Airway stent placement is an effective treatment for the immediate palliation of malignant airway obstruction. However, restenosis caused by tumor ingrowth and/or overgrowth after stenting is common. The purpose of this study was to investigate the feasibility and safety of a novel self-expandable stent loaded with 125 I seeds in healthy beagle dog. Under fluoroscopic guidance, forty-eight self-expandable airway stents loaded with 125 I seeds were perorally placed in the main trachea of 48 healthy beagle dogs, who were randomly divided into four groups (Group A: 0.3 mCi; Group B: 0.6 mCi; Group C: 0.9 mCi; Control group: 0 mCi). The estimated radiation dose was calculated using the isotropic point source approximation. Radiological follow-up examinations and histopathological examinations of stented tracheal segments and their adjacent organs and tissues were performed at 2, 4, 8, and 16 weeks following the stenting. All stents were successfully deployed in the targeted tracheal segment in the beagle dogs without procedure-related complications. Tracheal stenosis became severe gradually in all the four groups, which was not associated with the radioactivity of 125 I seeds (p > 0.05). The tracheal injury scores increased along with the higher dose of radioactive seeds which reached peak at 8 weeks and then turned back slightly at 16 weeks. The adjacent tissue did not show pathohistological changes under microscope, while mild and reversible ultrastructure changes were showed under electronic microscope. This study demonstrates that it is feasible and safe to insert this novel self-expandable airway stent loaded with 125 I seeds in healthy beagle dog.

  5. Clinical outcomes, quality of life, advantages and disadvantages of metal stent placement in the upper gastrointestinal tract.

    PubMed

    Vlavianos, Panagiotis; Zabron, Abigail

    2012-03-01

    This review will discuss the immediate- and long-term success, complications and overall benefits of self-expandable metal stents (SEMSs) in malignant or benign obstruction of the oesophagus, stomach and duodenum. Over recent years, indications such as benign disease have expanded, as has SEMS diversity with self-expandable plastic stents (SEPSs) or fully covered and biodegradable stents, for example. SEMSs have been increasingly used in malignant upper gastrointestinal obstruction with many reports confirming efficacy, despite a significant complication rate. Fully covered stents are increasingly used for a variety of benign oesophageal disease, but their place in gastric outlet obstruction is still unclear. Covered and uncovered stents have different functional characteristics and stent type must be selected on an individual basis. Biodegradable stents show promise and the outcome of experience in larger patient cohorts is eagerly awaited. This area is an evolving field, in which the clinician requires up-to-date knowledge of therapeutic options to make individualized treatment choices in difficult clinical circumstances. Technical and clinical success for oesophageal or gastroduodenal SEMSs are then above 90%. Minor complications are common, but serious complications seldom occur. Biodegradable stents may be useful, especially when stenting is needed for a short period of time.

  6. Long-Term Outcomes of Double-Layered Polytetrafluoroethylene Membrane-Covered Self-Expandable Segmental Metallic Stents (Uventa) in Patients with Chronic Ureteral Obstructions: Is It Really Safe?

    PubMed

    Kim, Myong; Hong, Bumsik; Park, Hyung Keun

    2016-12-01

    To evaluate the long-term clinical efficacy and safety of double-layered polytetrafluoroethylene membrane-covered self-expandable segmental metallic stents (Uventa) in patients with chronic ureteral obstruction. In a retrospective study, a total of 50 ureter units (44 patients) with chronic obstructions were included from July 2010 to May 2015. Indications for Uventa placement were primary stenting for malignant ureteral obstruction, failed conventional polymeric Double-J stent (PS), or percutaneous nephrostomy (PCN) technique, with comorbidities or fears limiting PS/PCN changes, or with irritation or pain due to PS/PCN. Patients underwent Uventa stent placement using the antegrade or retrograde approach. There were no immediate procedure-related complications, and all stents were placed in the proper sites. During the median follow-up of 30.9 (interquartile range [IQR], 8.1-49.0) months, the primary (no obstruction and no additional intervention) and overall success (no obstruction and no additional intervention except supplementary Uventa) was 30.0% and 34.0%, respectively. Moreover, 14 of 50 ureter units (28.0%) experienced major complications (≥Clavien-Dindo class IIIb), such as ureteroarterial fistula (three cases, 6.0%), ureteroenteric fistula (three, 6.0%), ureterovaginal fistula (one, 2.0%), ureter perforation (one, 2.0%), uncontrollable bleeding (one, 2.0%), and complete obstruction (five, 10.0%). On univariate analysis, major complications were associated with female (odds ratio [OR] = 6.000), cervical cancer (OR = 4.667), ureteral stricture length (≥6.0 cm, OR = 4.583), and placement duration (≥24.0 months, OR = 20.429; all p < 0.05). In long-term follow-up, the Uventa stent demonstrated poor treatment outcomes with frequent major complications in patients with chronic ureteral obstructions.

  7. Management of occluded metal stents in malignant biliary obstruction: similar outcomes with second metal stents compared to plastic stents

    PubMed Central

    Shah, Tilak; Desai, Svetang; Haque, Mahfuzul; Dakik, Hassan; Fisher, Deborah

    2013-01-01

    Background Covered or uncovered self expandable metallic stents (SEMS) placed in patients with malignant biliary obstruction can occlude in 19–40%, but optimal management is unclear. Aim We sought to summarize current evidence regarding management of occluded SEMS in patients with malignant biliary obstruction. Methods Two investigators independently searched Pubmed, Embase, and Web of Science using pre-defined search criteria, and reviewed bibliographies of included studies. Data were independently abstracted by two investigators, and analyzed using RevMan. We compared strategies of second SEMS versus plastic stents with respect to the following outcomes: rate of second stent re-occlusion, duration of second stent patency, and survival. Results Ten retrospective studies met inclusion criteria for the systematic review. Management options described were placement of an uncovered SEMS (n=125), covered SEMS (n=106), plastic stent (n=135), percutaneous biliary drain (n=7), mechanical cleaning (n=18), or microwave coagulation (n=7). Relative risk of re-occlusion was not significantly different in patients with second SEMS compared to plastic stents (RR 1.24, 95% CI 0.92, 1.67, I2= 0, p 0.16). Duration of second stent patency was not significantly different between patients who received second SEMS versus plastic stents (weighted mean difference 0.46, 95% CI −0.30, 1.23, I2=83%). Survival was not significantly different among patients who received plastic stents versus SEMS (weighted mean difference −1.13, 95% CI −2.33, 0.07, I2 86%, p 0.07). Conclusions Among patients with malignant biliary obstruction and occluded SEMS, available evidence suggests a strategy of placing a plastic stent may be as effective as second SEMS. Limitations of these findings were that all studies were retrospective and heterogeneity between studies was detected for two of the outcomes. PMID:22732833

  8. Structural Evaluation of Radially Expandable Cardiovascular Stents Encased in a Polyurethane Film

    NASA Technical Reports Server (NTRS)

    Trigwell, Steve; De, Samiran; Sharma, Rajesh; Mazumder, Malay K.; Mehta, Jawahar L.

    2004-01-01

    A method of encasing cardiovascular stents with an expandable polyurethane coating has been developed to provide a smooth homogeneous inner wall allowing for a confluent growth of endothelial cells. In this design, the metal wire stent structure is completely covered by the polyurethane film minimizing biocorrosion of the metal (stainless steel or nitinol), and providing a homogeneous surface for surface treatment and incorporation of various eluting drugs to prevent platelet aggregation while supporting endothelialization. The polyurethane surface was treated with a helium plasma for sterilization and promotes growth of cells. The paper details the performance of the coated film to expand with the metal stent up to 225 % during deployment. We present stress/strain behavior of polyurethane films, and subsequent plasma treatment of the surface and the adhesion of the coating to the stent structure upon expansion. A film of less than 25 tm was found to be sufficient for corrosion resistance and flexibility without producing any excess stress on the stent structure. Straining the film to 225 % and plasma modification did not affect the mechanical and surface properties while allowing for improved biocompatibility as determined by the critical surface tension, surface chemistry, and roughness.

  9. Self-expandable macroporous nitinol stents for transfemoral exclusion of aortic aneurysms in dogs: preliminary results.

    PubMed

    Hagen, B; Harnoss, B M; Trabhardt, S; Ladeburg, M; Fuhrmann, H; Franck, C

    1993-01-01

    This experimental study evaluated the feasibility of excluding artificially created aortic aneurysms in dogs with transfemorally inserted nitinol stents, serving as intraluminal bypass. Infrarenal aortic aneurysms were created in eleven dogs (28-35 kg) by end-to-end anastomosis of sacciform conduits. Single and double wire-knitted, macroporous, superelastic, self-expanding nitinol stents without any additional wrapping or in-between fabrics served as endovascular grafts. The pore size of the double-knitted stents was less than 0.7 mm2. Angiography following stent placement showed immediate exclusion of the aneurysms for the double-knitted stents. For the single-knitted stents (2 cases), partial exclusion was achieved only after considerable delay. CT studies in the dogs with the double-knitted stents revealed patency of the grafts after 3 to 5 weeks with the aneurysms totally thrombosed. So far gross pathology of 1 dog at 24 h and 1 at 12 months revealed patency of the stents. At 12 months histopathology showed a neointima covering the inner stent surface with the aneurysm filled by an organized thrombus. It is concluded, that an "open" stent with a tight meshwork appears to be a suitable device to instantly exclude artificial aneurysms of the canine aorta.

  10. Comparison of outcomes among secondary covered metallic, uncovered metallic, and plastic biliary stents in treating occluded primary metallic stents in malignant distal biliary obstruction.

    PubMed

    Cho, Jae Hee; Jeon, Tae Joo; Park, Jeong Youp; Kim, Hee Man; Kim, Yoon Jae; Park, Seung Woo; Chung, Jae Bock; Song, Si Young; Bang, Seungmin

    2011-02-01

    The self-expandable metallic stent (SEMS) has been widely used for unresectable malignant biliary obstruction but eventually becomes occluded by tumor ingrowth/overgrowth and sludge. Therefore, we aimed to determine the therapeutic effectiveness of secondary stents and to find differences according to various combinations of the first and second stents for the management of occluded SEMSs in patients with malignant distal biliary obstruction. Between 1999 and November 2008, 77 patients with malignant biliary obstruction underwent secondary biliary stent placement as "stent-in-stent" at three university hospitals in Korea (40 covered, 26 uncovered, and 11 plastic stents). The membrane of the covered SEMS was regarded as the barrier against tumor ingrowth. We categorized the patients into three groups based on whether the covered SEMS was either the first or the second stent: membrane-SEMS (18 covered-covered; 9 covered-uncovered; 22 uncovered-covered SEMS), bare-SEMS (17 uncovered-uncovered SEMS), and plastic stent (3 covered-plastic; 8 uncovered-plastic). The median patency of second stents was 138, 109, and 88 days (covered, uncovered, and plastic stents). The second covered SEMSs had a significantly longer patency than plastic stents (p=0.047). In a multivariate analysis including membrane-SEMS, bare-SEMS, and plastic stent groups, the bare-SEMS had a worse cumulative stent patency (HR=2.04, CI=1.08-3.86) and survival time (HR=2.37, CI=1.25-4.49) than the membrane-SEMS. Patients with ampulla of Vater cancer had better stent patency (HR=0.27, CI=0.08-0.98) and survival (HR=0.17, CI=0.04-0.77) than those with other pancreatobiliary malignancies. In addition, antitumor treatment prolonged survival time (HR=0.50, CI=0.26-0.99). The placement of additional biliary stents using the "stent-in-stent" method is an effective treatment for an occluded metallic primary stent. In addition, double biliary SEMS placement using at least one covered SEMS (in the primary and

  11. Biliary hemorrhage after removal of an expandable metallic stent during liver transplantation.

    PubMed

    Narumi, Shunji; Hakamda, Kenichi; Toyoki, Yoshikazu; Ishido, Keinosuke; Nara, Masaki; Yoshihara, Syuichi; Sasaki, Mutsuo

    2008-11-01

    The self-expandable metallic stent (SEMS) has become a common device for palliative treatment of malignant biliary obstructions or benign strictures. Despite the ease of placement of SEMSs, their removal has been reported to be very difficult. Here, we report a case with primary sclerosing cholangitis who developed massive hemorrhage after intraoperative removal of a SEMS. Possible living donor liver transplantation (LT) was considered for a 49-year-old female with primary sclerosing cholangitis. However, her general condition did not meet the criteria for LT; therefore, she was referred back to her primary physician. Two years later, she developed jaundice, and her primary physician placed multiple SEMSs, 1 of which was placed across the papilla of Vater. She was evaluated rapidly, and underwent living donor LT. During the operation, the common bile duct was examined and an incision was made. A stent was found firmly embedded in the bile duct. Each wire of the SEMS was pinched and then successfully pulled out 1 by 1. Finally, all parts of the SEMS were removed. Before creating the Roux-en-Y limb, hemorrhage from the remnant bile duct was confirmed by examination of the duodenum and bile duct stump. The bile duct was sewn internally with monofilament stitches and compressed for 10 minutes. Finally, hemostasis was brought about and transplantation was completed successfully. Despite some reports regarding successful endoscopic removal of SEMSs, its removal in patients with portal hypertension coagulopathy is risky. SEMSs should not be placed in patients who are candidates for LT.

  12. Study of the Behavior of a Bell-Shaped Colonic Self-Expandable NiTi Stent under Peristaltic Movements

    PubMed Central

    Puértolas, José A.; López, Enrique

    2013-01-01

    Managing bowel obstruction produced by colon cancer requires an emergency intervention to patients usually in poor conditions, and it requires creating an intestinal stoma in most cases. Regardless of that the tumor may be resectable, a two-stage surgery is mandatory. To avoid these disadvantages, endoscopic placement of self-expanding stents has been introduced more than 10 years ago, as an alternative to relieve colonic obstruction. It can be used as a bridge to elective single-stage surgery avoiding a stoma or as a definitive palliative solution in patients with irresectable tumor or poor estimated survival. Stents must be capable of exerting an adequate radial pressure on the stenosed wall, keeping in mind that stent must not move or be crushed, guaranteeing an adequate lumen when affected by peristaltic waves. A finite element simulation of bell-shaped nitinol stent functionality has been done. Catheter introduction, releasing at position, and the effect of peristaltic wave were simulated. To check the reliability of the simulation, a clinical experimentation with porcine specimens was carried out. The stent presented a good deployment and flexibility. Stent behavior was excellent, expanding from the very narrow lumen corresponding to the maximum peristaltic pressure to the complete recovery of operative lumen when the pressure disappears. PMID:23841067

  13. Future developments in biliary stenting

    PubMed Central

    Hair, Clark D; Sejpal, Divyesh V

    2013-01-01

    Biliary stenting has evolved dramatically over the past 30 years. Advancements in stent design have led to prolonged patency and improved efficacy. However, biliary stenting is still affected by occlusion, migration, anatomical difficulties, and the need for repeat procedures. Multiple novel plastic biliary stent designs have recently been introduced with the primary goals of reduced migration and improved ease of placement. Self-expandable bioabsorbable stents are currently being investigated in animal models. Although not US Food and Drug Administration approved for benign disease, fully covered self-expandable metal stents are increasingly being used in a variety of benign biliary conditions. In malignant disease, developments are being made to improve ease of placement and stent patency for both hilar and distal biliary strictures. The purpose of this review is to describe recent developments and future directions of biliary stenting. PMID:23837001

  14. Malignant Gastroduodenal Obstruction: Treatment with Self-Expanding Uncovered Wallstent

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gutzeit, Andreas, E-mail: Andreas.Gutzeit@ksw.ch; Binkert, Christoph A.; Schoch, Eric

    2009-01-15

    Purpose: To retrospectively evaluate the clinical effectiveness of a self-expanding uncovered Wallstent in patients with malignant gastroduodenal obstruction. Materials and Methods: Under combined endoscopic and fluoroscopic guidance, 29 patients with a malignant gastroduodenal stenosis were treated with a self-expanding uncovered metallic Wallstent. A dysphagia score was assessed before and after the intervention to measure the success of this palliative therapy. The dysphagia score ranged between grade 0 to grade 4: grade 0 = able to tolerate solid food, grade 1 = able to tolerate soft food, grade 2 = able to tolerate thick liquids, grade 3 = able to toleratemore » water or clear fluids, and grade 4 = unable to tolerate anything perorally. Stent patency and patients survival rates were calculated. Results: The insertion of the gastroduodenal stent was technically successful in 28 patients (96.5%). After stenting, 25 patients (86.2%) showed clinical improvement by at least one score point. During follow-up, 22 (78.5%) of 28 patients showed no stent occlusion until death and did not have to undergo any further intervention. In six patients (20.6%), all of whom were treated with secondary stent insertions, occlusion with tumor ingrowth and/or overgrowth was observed after the intervention. The median period of primary stent patency in our study was 240 days. Conclusion: Placement of an uncovered Wallstent is clinically effective in patients with malignant gastroduodenal obstruction. Stent placement is associated with high technical success, good palliation effect, and high durability of stent function.« less

  15. Self-Expanding Versus Balloon-Expandable Stents for Iliac Artery Occlusive Disease: The Randomized ICE Trial.

    PubMed

    Krankenberg, Hans; Zeller, Thomas; Ingwersen, Maja; Schmalstieg, Josefin; Gissler, Hans Martin; Nikol, Sigrid; Baumgartner, Iris; Diehm, Nicolas; Nickling, Estell; Müller-Hülsbeck, Stefan; Schmiedel, Rainer; Torsello, Giovanni; Hochholzer, Willibald; Stelzner, Christian; Brechtel, Klaus; Ito, Wulf; Kickuth, Ralph; Blessing, Erwin; Thieme, Marcus; Nakonieczny, Jaroslaw; Nolte, Thomas; Gareis, Ragnar; Boden, Harald; Sixt, Sebastian

    2017-08-28

    Atherosclerosis of iliac arteries is widespread. As inflow vessels, they are of great clinical significance and increasingly being treated by endovascular means. Most commonly, stents are implanted. So far, due to a lack of comparative data, no guideline recommendations on the preferable stent type, balloon-expandable stent (BE) or self-expanding stent (SE), have been issued. In this randomized, multicenter study, patients with moderate to severe claudication from common or external iliac artery occlusive disease were assigned 1:1 to either BE or SE. The primary endpoint was binary restenosis at 12 months as determined by duplex ultrasound. Key secondary endpoints were walking impairment, freedom from target lesion revascularization (TLR), hemodynamic success, target limb amputation, and all-cause death. Six hundred sixty patients with 660 lesions were enrolled at 18 German and Swiss sites over a period of 34 months; 24.8% of the patients had diabetes and 57.4% were current smokers. The common iliac artery was affected in 58.9%. One hundred nine (16.5%) lesions were totally occluded and 25.6% heavily calcified. Twelve-month incidence of restenosis was 6.1% after SE implantation and 14.9% after BE implantation (p = 0.006). Kaplan-Meier estimate of freedom from TLR was 97.2% and 93.6%, respectively (p = 0.042). There was no between-group difference in walking impairment, hemodynamic success, amputation rate, all-cause death, or periprocedural complications. The treatment of iliac artery occlusive disease with SE as compared with BE resulted in a lower 12-month restenosis rate and a significantly reduced TLR rate. No safety concerns arose in both groups. (Iliac, Common and External [ICE] Artery Stent Trial; NCT01305174). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  16. Percutaneous stent placement for the treatment of malignant biliary obstruction: nitinol versus elgiloy stents.

    PubMed

    Zurstrassen, Charles Edouard; Bitencourt, Almir Galvão Vieira; Guimaraes, Marcos Duarte; Cavalcante, Aline Cristine Barbosa Santos; Tyng, Chiang Jeng; Amoedo, Mauricio Kauark; Matsushita Junior, João Paulo Kawaoka; Szklaruk, Janio; Marchiori, Edson; Chojniak, Rubens

    2017-01-01

    This study aimed to compare two self-expanding stents, a nitinol stent and an elgiloy stent, both placed percutaneously, in terms of their efficacy in palliating inoperable malignant biliary obstruction. We retrospectively investigated 99 patients with unresectable malignant biliary obstruction treated with percutaneous placement of a self-expanding metallic stent at our institution between May 2007 and January 2010. Serum bilirubin and liver enzyme levels were measured before and 30 days after stenting. For all procedures using elgiloy or nitinol stents, stent occlusion and patient survival rates were calculated using Kaplan-Meyer analysis. All of the patients showed clinical improvement after stent placement, with no difference between the two groups. In both groups, the occlusion-free survival rate was 67% at 30 days, 37% at 90 days, 25% at 180 days, and 10% at 360 days, with no significant difference in relation to the type of stent. The two stents evaluated showed comparable efficacy for the percutaneous treatment of unresectable biliary malignancy, with good clinical results.

  17. Histological Evaluation of a Self-Expanding Stent-Graft 23 Months After Implantation in the Superficial Femoral Artery.

    PubMed

    Ishihara, Takayuki; Iida, Osamu; Inoue, Katsumi; Fujita, Masashi; Masuda, Masaharu; Okamoto, Shin; Nanto, Kiyonori; Kanda, Takashi; Tsujimura, Takuya; Sunaga, Akihiro; Mano, Toshiaki; Uematsu, Masaaki

    2017-10-01

    To report histological examination of a Viabahn stent-graft implanted in the superficial femoral artery (SFA) for nearly 2 years. A 78-year-old man with peripheral artery disease was treated successfully with a 6.0×250-mm Viabahn self-expanding stent-graft in the right SFA, relieving his lower limb claudication. The patient died suddenly due to acute myocardial infarction 23 months later. Histological evaluation of the stent-graft implantation site revealed moderate neointimal proliferation at both proximal and distal edges of the device. In the middle part of the stent, significant macrophages and multinucleated foreign body giant cells had accumulated, although the stent was entirely patent. Furthermore, no endothelial cell coverage was found. Judging from these features, it might be necessary to continue dual antiplatelet therapy after stent-graft implantation over the long term to prevent thrombosis and subsequent restenosis or reocclusion.

  18. Temporary placement of retrievable fully covered metallic stents versus percutaneous balloon dilation in the treatment of benign biliary strictures.

    PubMed

    Kim, Jin Hyoung; Gwon, Dong Il; Ko, Gi-Young; Sung, Kyu-Bo; Lee, Sung Koo; Yoon, Hyun-Ki; Shin, Ji Hoon; Song, Ho-Young

    2011-06-01

    To compare retrospectively percutaneous transhepatic primary placement of a retrievable self-expanding metallic stent with percutaneous balloon dilation for the treatment of benign biliary strictures. From 2005-2009, 66 patients with benign biliary strictures in whom an endoscopic approach failed or in whom such an approach was inaccessible were evaluated. Of 66 patients, 31 underwent balloon dilation, and 35 underwent temporary metallic stent placement. The etiologies of the benign strictures were anastomotic stricture after surgery (n = 54), stricture secondary to intraoperative injury (n = 9), inflammatory stricture (n = 2), and stricture secondary to trauma (n = 1). The primary patency rates were significantly better in the stent group (87% at 3 years) than in the balloon group (44% at 3 years; P = .022). The indwelling period of percutaneous transhepatic biliary drainage (PTBD) catheters after the initial procedure was able to be significantly reduced in the stent group (median 2.5 months) compared with the balloon group (median 4.5 months; P = .001). Significant bleeding (associated with PTBD) occurred in one patient in the balloon group. In the stent group, stent migration occurred in two patients, and one patient underwent surgery for stent removal after failure of removal under fluoroscopic guidance. Percutaneous primary placement of a retrievable self-expanding metallic stent showed superior intermediate-term results compared with percutaneous balloon dilation for the treatment of benign biliary strictures. In addition, the indwelling period of PTBD catheters can be significantly reduced using temporary stent placement. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

  19. Endovascular treatment of post-thrombotic and non-thrombotic iliofemoral venous outflow obstructions with self-expanding nitinol stents.

    PubMed

    Stuck, Anna K; Reich, Thomas; Engelberger, Rolf P; Sebastian, Tim; Kucher, Nils

    2018-06-01

    The aim of the study was to investigate venous patency and clinical outcomes for endovascular treatment of iliofemoral venous obstruction in patients with post-thrombotic syndrome (PTS) and non-thrombotic iliac vein lesion (NIVL) with dedicated self-expanding nitinol stents. Data were collected from the prospective Swiss Venous Stent Registry, enrolling consecutive patients with a standardized follow-up procedure since January 2008. Patency was evaluated by duplex sonography and clinical outcome by various scores including the Villalta score at baseline, three, six, and 12 months, and then annually after endovascular therapy. Overall, 93 patients (64 PTS, 29 NIVL) were analysed. Mean follow-up time was 20 ± 16 (range 3-70) months. A total of 11 (12 %) patients had a stent occlusion, all of which occurred in the PTS group, and 13 (14 %) patients had a symptomatic stent stenosis. Primary patency was 79 % (95 % CI 68-87 %) at 12 months and 72 % (95 % CI 59-82 %) at 24 months. In PTS patients, primary patency at 12 months was 75 % (95 % CI 61-84 %) vs. 89 % (95 % CI 63-97 %) in NIVL patients (p = 0.10). Secondary patency at 24 months was 94 % (95 % CI 84-98 %) in PTS and 100 % in NIVL, p = 0.19). Overall, 62 (67 %) patients were free from PTS at the latest follow-up with a Villalta score < 5 points. Predictive factors for the loss of primary patency were stents placed below the inguinal ligament (OR 2.59, 95 % CI, 0.99-6.84, p = 0.05). In symptomatic patients with chronic iliofemoral vein obstruction, endovascular therapy with self-expanding nitinol stents was associated with favourable patency rates and clinical improvement in the majority of patients.

  20. Stents for colorectal obstruction: Past, present, and future

    PubMed Central

    Kim, Eui Joo; Kim, Yoon Jae

    2016-01-01

    Since the development of uncovered self-expanding metal stents (SEMS) in the 1990s, endoscopic stents have evolved dramatically. Application of new materials and new designs has expanded the indications for enteral SEMS. At present, enteral stents are considered the first-line modality for palliative care, and numerous types of enteral stents are under development for extended clinical usage, beyond a merely palliative purpose. Herein, we will discuss the current status and the future development of lower enteral stents. PMID:26811630

  1. Endoscopic management of occluded metal biliary stents: metal versus 10F plastic stents.

    PubMed

    Yoon, Won Jae; Ryu, Ji Kon; Lee, Jung Won; Ahn, Dong-Won; Kim, Yong-Tae; Yoon, Yong Bum; Woo, Sang Myung; Lee, Woo Jin

    2010-11-14

    To compare the efficacy of self-expandable metal stents (SEMSs) with 10F plastic stents (PSs) in the endoscopic management of occluded SEMSs. We retrospectively reviewed the medical records of 56 patients who underwent SEMS insertion for palliation of unresectable malignant biliary obstruction between 2000 and 2007 and subsequent endoscopic retrograde biliary drainage (ERBD) with SEMS or PS for initial SEMS occlusion between 2000 and 2008. Subsequent ERBD with SEMS was performed in 29 patients and with PS in 27. The median time to stent occlusion after subsequent ERBD was 186 d in the SEMS group and 101 d in the PS group (P = 0.118). Overall median stent patency was 79 d for the SEMS group and 66 d for the PS group (P = 0.379). The mean number of additional biliary drainage procedures after subsequent ERBD in patients that died (n = 50) during the study period was 2.54 ± 4.12 for the SEMS group and 1.85 ± 1.95 for the PS group (P = 0.457). The mean total cost of additional biliary drainage procedures after the occlusion of subsequent SEMS or PS was $410.04 ± 692.60 for the SEMS group and $630.16 ± 671.63 for the PS group (P = 0.260). Tumor ingrowth as the cause of initial SEMS occlusion was the only factor associated with a shorter time to subsequent stent occlusion (101 d for patients with tumor ingrowth vs 268 d for patients without tumor ingrowth, P = 0.008). Subsequent ERBD with PSs offered similar patency and number of additional biliary drainage procedures compared to SEMSs in the management of occluded SEMS.

  2. Palliative radiotherapy in addition to self-expanding metal stent for improving dysphagia and survival in advanced oesophageal cancer (ROCS: Radiotherapy after Oesophageal Cancer Stenting): study protocol for a randomized controlled trial.

    PubMed

    Adamson, Douglas; Blazeby, Jane; Nelson, Annmarie; Hurt, Chris; Nixon, Lisette; Fitzgibbon, Jim; Crosby, Tom; Staffurth, John; Evans, Mim; Kelly, Noreen Hopewell; Cohen, David; Griffiths, Gareth; Byrne, Anthony

    2014-10-22

    The single most distressing symptom for patients with advanced esophageal cancer is dysphagia. Amongst the more effective treatments for relief of dysphagia is insertion of a self-expanding metal stent (SEMS). It is possible that the addition of a palliative dose of external beam radiotherapy may prolong the relief of dysphagia and provide additional survival benefit. The ROCS trial will assess the effect of adding palliative radiotherapy after esophageal stent insertion. The study is a randomized multicenter phase III trial, with an internal pilot phase, comparing stent alone versus stent plus palliative radiotherapy in patients with incurable esophageal cancer. Eligible participants are those with advanced esophageal cancer who are in need of stent insertion for primary management of dysphagia. Radiotherapy will be administered as 20 Gray (Gy) in five fractions over one week or 30 Gy in 10 fractions over two weeks, within four weeks of stent insertion. The internal pilot will assess rates and methods of recruitment; pre-agreed criteria will determine progression to the main trial. In total, 496 patients will be randomized in a 1:1 ratio with follow up until death. The primary outcome is time to progression of patient-reported dysphagia. Secondary outcomes include survival, toxicity, health resource utilization, and quality of life. An embedded qualitative study will explore the feasibility of patient recruitment by examining patients' motivations for involvement and their experiences of consent and recruitment, including reasons for not consenting. It will also explore patients' experiences of each trial arm. The ROCS study will be a challenging trial studying palliation in patients with a poor prognosis. The internal pilot design will optimize methods for recruitment and data collection to ensure that the main trial is completed on time. As a pragmatic trial, study strengths include collection of all follow-up data in the usual place of care, and a focus on

  3. Covered self-expanding metal stents may be preferable to plastic stents in the treatment of chronic pancreatitis-related biliary strictures: a systematic review comparing 2 methods of stent therapy in benign biliary strictures.

    PubMed

    Siiki, Antti; Helminen, Mika; Sand, Juhani; Laukkarinen, Johanna

    2014-08-01

    Covered self-expanding metal stents (CSEMS) are being increasingly used in the endoscopic treatment of benign biliary strictures (BBS). There is no solid evidence yet to support their routine use. To evaluate feasibility, success rate, and complications of CSEMS compared with multiple plastic stents (PS) in BBS in a systematic review. A systematic search of electronic databases (Medline, Scopus, and Embase) for studies published from 2000 to 2012 combined to hand-search of reference lists resulted 4977 articles. Out of 99 potentially relevant studies selected for full-text review, 12 CSEMS (376 patients) and 13 PS studies (570 patients) met the final inclusion criteria. A systematic review comparing the 2 methods was made using proportion meta-analysis. A tendency to successful use of CSEMS in strictures related to chronic pancreatitis (CP) was shown: clinical success of 77% and 33% [95% confidence interval (CI), 61%-94% vs. 4%-63%, P=0.06] was achieved with CSEMS and PS at 12 months follow-up, respectively. There were no differences in the success rates of other etiologies except CP or in the early complications. In CSEMS, incidence of late adverse events was lower in CP-related strictures (3% vs. 67%, 95% CI, 0%-13% vs. 17%-99%, P=0.02). The median number of endoscopic retrograde cholangiopancreatographies was lower with CSEMSs: 1.5 versus 3.9 (P=0.002). Improved clinical success with fewer endoscopic sessions and corresponding complication rate may be achieved with CSEMS treatment compared with PS in BBS secondary to CP. In other BBS etiologies, this systematic review remains inconclusive.

  4. A non-randomized study in consecutive patients with postcholecystectomy refractory biliary leaks who were managed endoscopically with the use of multiple plastic stents or fully covered self-expandable metal stents (with videos).

    PubMed

    Canena, Jorge; Liberato, Manuel; Meireles, Liliane; Marques, Inês; Romão, Carlos; Coutinho, António Pereira; Neves, Beatriz Costa; Veiga, Pedro Mota

    2015-07-01

    Endoscopic management of postcholecystectomy biliary leaks is widely accepted as the treatment of choice. However, refractory biliary leaks after a combination of biliary sphincterotomy and the placement of a large-bore (10F) plastic stent can occur, and the optimal rescue endotherapy for this situation is unclear. To compare the clinical effectiveness of the use of a fully covered self-expandable metal stent (FCSEMS) with the placement of multiple plastic stents (MPS) for the treatment of postcholecystectomy refractory biliary leaks. Prospective study. Two tertiary-care referral academic centers and one general district hospital. Forty consecutive patients with refractory biliary leaks who underwent endoscopic management. Temporary placement of MPS (n = 20) or FCSEMSs (n = 20). Clinical outcomes of endotherapy as well as the technical success, adverse events, need for reinterventions, and prognostic factors for clinical success. Endotherapy was possible in all patients. After endotherapy, closure of the leak was accomplished in 13 patients (65%) who received MPS and in 20 patients (100%) who received FCSEMSs (P = .004). The Kaplan-Meier (log-rank) leak-free survival analysis showed a statistically significant difference between the 2 patient populations (χ(2) [1] = 8.30; P < .01) in favor of the FCSEMS group. Use of <3 plastic stents (P = .024), a plastic stent diameter <20F (P = .006), and a high-grade biliary leak (P = .015) were shown to be significant predictors of treatment failure with MPS. The 7 patients in whom placement of MPS failed were retreated with FCSEMSs, resulting in closure of the leaks in all cases. Non-randomized design. In our series, the results of the temporary placement of FCSEMSs for postcholecystectomy refractory biliary leaks were superior to those from the use of MPS. A randomized study is needed to confirm our results before further recommendations. Copyright © 2015 American Society for Gastrointestinal Endoscopy

  5. A prospective multicenter study on self-expandable metallic stents as a bridge to surgery for malignant colorectal obstruction in Japan: efficacy and safety in 312 patients.

    PubMed

    Saito, Shuji; Yoshida, Shuntaro; Isayama, Hiroyuki; Matsuzawa, Takeaki; Kuwai, Toshio; Maetani, Iruru; Shimada, Mamoru; Yamada, Tomonori; Tomita, Masafumi; Koizumi, Koichi; Hirata, Nobuto; Kanazawa, Hideki; Enomoto, Toshiyuki; Sekido, Hitoshi; Saida, Yoshihisa

    2016-09-01

    Endoscopic stenting with a self-expandable metallic stent (SEMS) is a widely accepted procedure for malignant colonic obstruction. The Colonic Stent Safe Procedure Research Group conducted the present prospective feasibility study. Our objectives were to estimate the safety and feasibility of SEMS placement as a bridge to surgery (BTS) for malignant colorectal obstruction. We conducted a prospective, observational, single-arm, multicenter clinical trial from March 2012 to October 2013. Each patient was treated with an uncovered WallFlex enteral colonic stent. Patients were followed up until discharge after surgery. A total of 518 consecutive patients were enrolled in this study. The cohort intended for BTS consisted of 312 patients (61 %), and the stent could be released in 305 patients. Technical and clinical success rates were 98 and 92 %, respectively. Elective surgery was performed in 297 patients, and emergency surgery was performed in eight patients for the treatment of complications. The overall preoperative complication rate was 7.2 %. Major complications, including perforation, occurred in 1.6 %, persistent colonic obstruction occurred in 1.0 %, and stent migration occurred in 1.3 % patients. The median time from SEMS to surgery was 16 days. Silent perforations were observed in 1.3 %. Open and laparoscopic surgery was performed in 121 and 184 patients, respectively. The tumor could be resected in 297 patients. The primary anastomosis rate was 92 %. The rate of anastomotic leakage was 4 %, and the overall stoma creation rate was 10 %. The median duration of hospitalization following surgery was 12 days. Overall postoperative morbidity and mortality rates were 16 and 0.7 %, respectively. This largest, multicenter, prospective study demonstrates the feasibility of SEMS placement as a BTS for malignant colorectal obstruction. SEMS serves as a safe and effective BTS with acceptable stoma creation and complication rates in patients with acute

  6. Temporary placement of metallic stent could lead to long-term benefits for benign tracheobronchial stenosis.

    PubMed

    Zhou, Guo-Wu; Huang, Hai-Dong; Sun, Qin-Ying; Xiong, Ye; Li, Qiang; Dong, Yu-Chao; Zhang, Wei

    2015-12-01

    The permanent placement of metallic stent for benign tracheobronchial stenosis (BTS) was controversial. This study was conducted to evaluate the long-term outcomes of temporary placement of metallic stent for BTS. The BTS patients who received temporary placement of retrievable self-expanded metallic stents were included between 2008 and 2011. Pre-stenting and follow-up respiratory status was analyzed. And symptom recurrence-free survival (SRFS) was assessed. A total of 49 stents were successfully temporarily placed in 40 consecutive BTS patients whose etiologies included endobronchial tuberculosis (EBTB) (n=22), post-tracheostomy stenosis (n=10), post-intubation stenosis (n=6) and post radiotherapy stricture (n=2). All stents were removed integrally after a median 18 days' stenting period, without major complications. During the median 27 months follow-up period after stent removal, a total of 22 patients were free of recurrence. And the overall 3-year SRFS rate was 52.0%. According to the etiology, the 3-year SRFS rates were 59.1% and 42.9% in the patients with EBTB and non-EBTB, respectively. Compared with pre-stenting, the follow-up internal diameter of stricture, Hugh-Jones scale, 6-minute walk test (6MWT) and percentage of forced expiratory volume in one second (FEV1%) were significantly improved. Multivariate analysis suggested that granulation tissue growth and tracheobronchial malacia might be independent factors of poor prognosis. Temporary placement of retrievable metallic stent may be an alternative treatment for BTS patients.

  7. Fully covered stents versus partially covered stents for palliative treatment of esophageal cancer: Is there a difference?

    PubMed

    Alonso Lárraga, J O; Flores Carmona, D Y; Hernández Guerrero, A; Ramírez Solís, M E; de la Mora Levy, J G; Sánchez Del Monte, J C

    2018-02-26

    Malignant dysphagia is difficulty swallowing resulting from esophageal obstruction due to cancer. The goal of palliative treatment is to reduce the dysphagia and improve oral dietary intake. Self-expandable metallic stents are the current treatment of choice, given that they enable the immediate restoration of oral intake. The aim of the present study was to describe the results of using totally covered and partially covered esophageal stents for palliating esophageal cancer. A retrospective study was conducted on patients with inoperable esophageal cancer treated with self-expandable metallic stents. The 2 groups formed were: group A, which consisted of patients with a fully covered self-expandable stent (SX-ELLA ® ), and group B, which was made up of patients with a partially covered self-expandable stent (Ultraflex ® ). Of the 69-patient total, 50 were included in the study. Group A had 19 men and 2 women and their mean age was 63.6 years (range 41-84). Technical success was achieved in 100% (n=21) of the cases and clinical success in 90.4% (n=19). Group B had 24 men and 5 women and their mean age was 67.5 years (range 43-92). Technical success was achieved in 100% (n=29) of the cases and clinical success in 89.6% (n=26). Complications were similar in both groups (33.3 vs. 51.7%). There was no difference between the 2 types of stent for the palliative treatment of esophageal cancer with respect to technical success, clinical success, or complications. Copyright © 2018 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

  8. Comparison of patency and cost-effectiveness of self-expandable metal and plastic stents used for malignant biliary strictures: a Polish single-center study.

    PubMed

    Budzyńska, Agnieszka; Nowakowska-Duława, Ewa; Marek, Tomasz; Hartleb, Marek

    2016-10-01

    Most patients with malignant biliary obstruction are suited only for palliation by endoscopic drainage with plastic stents (PS) or self-expandable metal stents (SEMS). To compare the clinical outcome and costs of biliary stenting with SEMS and PS in patients with malignant biliary strictures. A total of 114 patients with malignant jaundice who underwent 376 endoscopic retrograde biliary drainage (ERBD) were studied. ERBD with the placement of PS was performed in 80 patients, with one-step SEMS in 20 patients and two-step SEMS in 14 patients. Significantly fewer ERBD interventions were performed in patients with one-step SEMS than PS or the two-step SEMS technique (2.0±1.12 vs. 3.1±1.7 or 5.7±2.1, respectively, P<0.0001). The median hospitalization duration per procedure was similar for the three groups of patients. The patients' survival time was the longest in the two-step SEMS group in comparison with the one-step SEMS and PS groups (596±270 vs. 276±141 or 208±219 days, P<0.001). Overall median time to recurrent biliary obstruction was 89.3±159 days for PS and 120.6±101 days for SEMS (P=0.01). The total cost of hospitalization with ERBD was higher for two-step SEMS than for one-step SEMS or PS (1448±312, 1152±135 and 977±156&OV0556;, P<0.0001). However, the estimated annual cost of medical care for one-step SEMS was higher than that for the two-step SEMS or PS groups (4618, 4079, and 3995&OV0556;, respectively). Biliary decompression by SEMS is associated with longer patency and reduced number of auxiliary procedures; however, repeated PS insertions still remain the most cost-effective strategy.

  9. Endoscopic management of occluded metal biliary stents: Metal versus 10F plastic stents

    PubMed Central

    Yoon, Won Jae; Ryu, Ji Kon; Lee, Jung Won; Ahn, Dong-Won; Kim, Yong-Tae; Yoon, Yong Bum; Woo, Sang Myung; Lee, Woo Jin

    2010-01-01

    AIM: To compare the efficacy of self-expandable metal stents (SEMSs) with 10F plastic stents (PSs) in the endoscopic management of occluded SEMSs. METHODS: We retrospectively reviewed the medical records of 56 patients who underwent SEMS insertion for palliation of unresectable malignant biliary obstruction between 2000 and 2007 and subsequent endoscopic retrograde biliary drainage (ERBD) with SEMS or PS for initial SEMS occlusion between 2000 and 2008. RESULTS: Subsequent ERBD with SEMS was performed in 29 patients and with PS in 27. The median time to stent occlusion after subsequent ERBD was 186 d in the SEMS group and 101 d in the PS group (P = 0.118). Overall median stent patency was 79 d for the SEMS group and 66 d for the PS group (P = 0.379). The mean number of additional biliary drainage procedures after subsequent ERBD in patients that died (n = 50) during the study period was 2.54 ± 4.12 for the SEMS group and 1.85 ± 1.95 for the PS group (P = 0.457). The mean total cost of additional biliary drainage procedures after the occlusion of subsequent SEMS or PS was $410.04 ± 692.60 for the SEMS group and $630.16 ± 671.63 for the PS group (P = 0.260). Tumor ingrowth as the cause of initial SEMS occlusion was the only factor associated with a shorter time to subsequent stent occlusion (101 d for patients with tumor ingrowth vs 268 d for patients without tumor ingrowth, P = 0.008). CONCLUSION: Subsequent ERBD with PSs offered similar patency and number of additional biliary drainage procedures compared to SEMSs in the management of occluded SEMS. PMID:21072899

  10. Partially Covered Metal Stents May Not Prolong Stent Patency Compared to Uncovered Stents in Unresectable Malignant Distal Biliary Obstruction.

    PubMed

    Kim, Jae Yun; Ko, Gyu Bong; Lee, Tae Hoon; Park, Sang-Heum; Lee, Yun Nah; Cho, Young Sin; Jung, Yunho; Chung, Il-Kwun; Choi, Hyun Jong; Cha, Sang-Woo; Moon, Jong Ho; Cho, Young Deok; Kim, Sun-Joo

    2017-05-15

    Controversy still exists regarding the benefits of covered self-expandable metal stents (SEMSs) compared to uncovered SEMSs. We aimed to compare the patency and stent-related adverse events of partially covered SEMSs (PC-SEMSs) and uncovered SEMSs in unresectable malignant distal biliary obstruction. A total of 134 patients who received a PC-SEMS or uncovered SEMS for palliation of unresectable malignant distal biliary obstruction were reviewed retrospectively. The main outcome measures were stent patency, stent-related adverse events, and overall survival. The median stent patency was 118 days (range, 3 to 802 days) with PC-SEMSs and 105 days (range, 2 to 485 days) with uncovered SEMSs (p=0.718). The overall endoscopic revision rate due to stent dysfunction was 36.6% (26/71) with PC-SEMSs and 36.5% (23/63) with uncovered SEMSs (p=0.589). Tumor ingrowth was more frequent with uncovered SEMSs (4.2% vs 19.1%, p=0.013), but migration was more frequent with PC-SEMSs (11.2% vs 1.5%, p=0.04). The incidence of stent-related adverse events was 2.8% (2/71) with PC-SEMSs and 9.5% (6/63) with uncovered SEMSs (p=0.224). The median overall survival was 166 days with PC-SEMSs and 168 days with uncovered SEMSs (p=0.189). Compared to uncovered SEMSs, PC-SEMSs did not prolong stent patency in unresectable malignant distal biliary obstruction. Stent migration was more frequent with PC-SEMSs. However, tumor ingrowth was less frequent with PC-SEMSs compared to uncovered SEMSs.

  11. Partially Covered Metal Stents May Not Prolong Stent Patency Compared to Uncovered Stents in Unresectable Malignant Distal Biliary Obstruction

    PubMed Central

    Kim, Jae Yun; Ko, Gyu Bong; Lee, Tae Hoon; Park, Sang-Heum; Lee, Yun Nah; Cho, Young Sin; Jung, Yunho; Chung, Il-Kwun; Choi, Hyun Jong; Cha, Sang-Woo; Moon, Jong Ho; Cho, Young Deok; Kim, Sun-Joo

    2017-01-01

    Background/Aims Controversy still exists regarding the benefits of covered self-expandable metal stents (SEMSs) compared to uncovered SEMSs. We aimed to compare the patency and stent-related adverse events of partially covered SEMSs (PC-SEMSs) and uncovered SEMSs in unresectable malignant distal biliary obstruction. Methods A total of 134 patients who received a PC-SEMS or uncovered SEMS for palliation of unresectable malignant distal biliary obstruction were reviewed retrospectively. The main outcome measures were stent patency, stent-related adverse events, and overall survival. Results The median stent patency was 118 days (range, 3 to 802 days) with PC-SEMSs and 105 days (range, 2 to 485 days) with uncovered SEMSs (p=0.718). The overall endoscopic revision rate due to stent dysfunction was 36.6% (26/71) with PC-SEMSs and 36.5% (23/63) with uncovered SEMSs (p=0.589). Tumor ingrowth was more frequent with uncovered SEMSs (4.2% vs 19.1%, p=0.013), but migration was more frequent with PC-SEMSs (11.2% vs 1.5%, p=0.04). The incidence of stent-related adverse events was 2.8% (2/71) with PC-SEMSs and 9.5% (6/63) with uncovered SEMSs (p=0.224). The median overall survival was 166 days with PC-SEMSs and 168 days with uncovered SEMSs (p=0.189). Conclusions Compared to uncovered SEMSs, PC-SEMSs did not prolong stent patency in unresectable malignant distal biliary obstruction. Stent migration was more frequent with PC-SEMSs. However, tumor ingrowth was less frequent with PC-SEMSs compared to uncovered SEMSs. PMID:28208003

  12. Biodegradable stents for the treatment of refractory or recurrent benign esophageal stenosis.

    PubMed

    Imaz-Iglesia, Iñaki; García-Pérez, Sonia; Nachtnebel, Anna; Martín-Águeda, Belén; Sánchez-Piedra, Carlos; Karadayi, Bilgehan; Demirbaş, Ali Rıza

    2016-06-01

    Esophageal stents are used for the treatment of refractory and recurrent dyphagias. In 2007, esophageal biodegradable stents (EBS) were authorised as an alternative to existing metal and plastic stents in Europe. The advantages claimed for EBS are fewer complications concerning tissue ingrowth, stent migration and stent removal. We performed a systematic review to evaluate the efficacy and safety of EBS compared to fully-covered self-expanding metal stents, self-expanding plastic stents, and esophageal dilation for the treatment of refractory or recurrent benign esophageal stenosis. Three comparative studies (one randomized controlled trial and two cohort studies) were assessed. The studies used different inclusion criteria, had a very small (sample) size and the quality of the evidence was very low. Expert commentary: The current evidence is insufficient to determine the relative efficacy or safety of esophageal biodegradable stents. The results of this systematic review should be updated once new evidence is available.

  13. A new approach to endoscopic treatment of tumors of the esophagogastric junction with individually designed self-expanding metal stents

    PubMed Central

    Aymaz, Serhat; Dormann, Arno J

    2008-01-01

    The incidence of adenocarcinoma of the esophago-gastric junction is constantly increasing. Curative treatment is no longer possible at the time of diagnosis in more than 50% of patients with esophageal carcinoma, and palliative treatment focusing on eliminating dysphagia is required. Endoscopic therapy with stent implantation is an established method of achieving this. It can be carried out quickly, with a low rate of early complications, and leads to fast symptomatic improvement, assessed using the dysphagia score. The relatively high rate of late complications such as stent migration, hemorrhage, and gastroesophageal mucosal prolapse has led to recent debate on the role of metal stents in palliative therapy. We present here a new type of stent design for transcardial application, which is intended to prevent bleeding due to mechanical mucosal lesions caused by the distal end of the stent extending into the stomach. The further intention of this case report is to force the discussion on individually designed nitinol stents in special anatomic conditions. PMID:18609720

  14. A Critical Review on Metallic Glasses as Structural Materials for Cardiovascular Stent Applications.

    PubMed

    Jafary-Zadeh, Mehdi; Praveen Kumar, Gideon; Branicio, Paulo Sergio; Seifi, Mohsen; Lewandowski, John J; Cui, Fangsen

    2018-02-27

    Functional and mechanical properties of novel biomaterials must be carefully evaluated to guarantee long-term biocompatibility and structural integrity of implantable medical devices. Owing to the combination of metallic bonding and amorphous structure, metallic glasses (MGs) exhibit extraordinary properties superior to conventional crystalline metallic alloys, placing them at the frontier of biomaterials research. MGs have potential to improve corrosion resistance, biocompatibility, strength, and longevity of biomedical implants, and hence are promising materials for cardiovascular stent applications. Nevertheless, while functional properties and biocompatibility of MGs have been widely investigated and validated, a solid understanding of their mechanical performance during different stages in stent applications is still scarce. In this review, we provide a brief, yet comprehensive account on the general aspects of MGs regarding their formation, processing, structure, mechanical, and chemical properties. More specifically, we focus on the additive manufacturing (AM) of MGs, their outstanding high strength and resilience, and their fatigue properties. The interconnection between processing, structure and mechanical behaviour of MGs is highlighted. We further review the main categories of cardiovascular stents, the required mechanical properties of each category, and the conventional materials have been using to address these requirements. Then, we bridge between the mechanical requirements of stents, structural properties of MGs, and the corresponding stent design caveats. In particular, we discuss our recent findings on the feasibility of using MGs in self-expandable stents where our results show that a metallic glass based aortic stent can be crimped without mechanical failure. We further justify the safe deployment of this stent in human descending aorta. It is our intent with this review to inspire biodevice developers toward the realization of MG-based stents.

  15. A Critical Review on Metallic Glasses as Structural Materials for Cardiovascular Stent Applications

    PubMed Central

    Jafary-Zadeh, Mehdi; Praveen Kumar, Gideon

    2018-01-01

    Functional and mechanical properties of novel biomaterials must be carefully evaluated to guarantee long-term biocompatibility and structural integrity of implantable medical devices. Owing to the combination of metallic bonding and amorphous structure, metallic glasses (MGs) exhibit extraordinary properties superior to conventional crystalline metallic alloys, placing them at the frontier of biomaterials research. MGs have potential to improve corrosion resistance, biocompatibility, strength, and longevity of biomedical implants, and hence are promising materials for cardiovascular stent applications. Nevertheless, while functional properties and biocompatibility of MGs have been widely investigated and validated, a solid understanding of their mechanical performance during different stages in stent applications is still scarce. In this review, we provide a brief, yet comprehensive account on the general aspects of MGs regarding their formation, processing, structure, mechanical, and chemical properties. More specifically, we focus on the additive manufacturing (AM) of MGs, their outstanding high strength and resilience, and their fatigue properties. The interconnection between processing, structure and mechanical behaviour of MGs is highlighted. We further review the main categories of cardiovascular stents, the required mechanical properties of each category, and the conventional materials have been using to address these requirements. Then, we bridge between the mechanical requirements of stents, structural properties of MGs, and the corresponding stent design caveats. In particular, we discuss our recent findings on the feasibility of using MGs in self-expandable stents where our results show that a metallic glass based aortic stent can be crimped without mechanical failure. We further justify the safe deployment of this stent in human descending aorta. It is our intent with this review to inspire biodevice developers toward the realization of MG-based stents

  16. Bench-top Comparison of Physical Properties of 4 Commercially-Available Self-Expanding Intracranial Stents

    PubMed Central

    Cho, Su-hee; Jo, Won-il; Jo, Ye-eun; Yang, Ku Hyun; Park, Jung Cheol

    2017-01-01

    Purpose To better understand the performance of four commercially available neurovascular stents in intracranial aneurysm embolization, the stents were compared in terms of their basic morphological and mechanical properties. Materials and Methods Four different types of stents that are currently being used for cerebral aneurysm embolization were prepared (two stents per type). Two were laser-cut stents (Neuroform and Enterprise) and two were braided from a single nitinol wire (LEO and LVIS stents). All were subjected to quantitative measurements of stent size, pore density, metal coverage, the force needed to load, push, and deploy the stent, radial force on deployment, surface roughness, and corrosion resistance. Results Compared to their nominal diameters, all stents had greater diameters after deployment. The length generally decreased after deployment. This was particularly marked in the braided stents. The braided stents also had higher pore densities than the laser-cut stents. Metal coverage was highest in the LEO stent (14%) and lowest in the Enterprise stent (5%). The LIVS stent had the highest microcatheter loading force (81.5 gf). The LEO stent had the highest passage force (55.0 gf) and deployment force (78.9 gf). The LVIS and LEO stents had the highest perpendicular (37.1 gf) and circumferential (178.4 gf) radial forces, respectively. The Enterprise stent had the roughest stent wire, followed by the LVIS, LEO, and Neuroform stents. Conclusion The four neurovascular stent types differed in terms of morphological and physical characteristics. An understanding of this diversity may help to decide which stent is most suitable for specific clinical situations. PMID:28316867

  17. Self-Expanding Nitinol Renal Artery Stents: Comparison of Safety and Efficacy of Bare Versus Polyzene-F Nanocoated Stents in a Porcine Model

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kurz, P.; Stampfl, U.; Christoph, P.

    2011-02-15

    Objective: To investigate the safety and efficacy of a Polyzene-F nanocoat on new low-profile self-expandable nitinol stents in minipig renal arteries. Materials and Methods: Ten bare nitinol stents (BNS) and 10 stents coated with a 50 nm-thin Polyzene-F coating were randomly implanted into renal arteries of 10 minipigs (4- and 12-week follow-up, 5 animals/group). Thrombogenicity, on-stent surface endothelialization, vessel wall injury, late in-stent stenosis, and peristrut vessel wall inflammation were determined by quantitative angiography and postmortem histomorphometry. Results: In 6 of 10 BNS, >50% stenosis was found, but no stenosis was found in stents with a nanothin Polyzene-F coating. Histomorphometrymore » showed a statistically significant (p < 0.05) different average maximum luminal loss of 55.16% {+-} 8.43% at 12 weeks in BNS versus 39.77% {+-} 7.41% in stents with a nanothin Polyzene-F coating. Stents with a nanothin Polyzene-F coating had a significantly (p < 0.05) lower inflammation score after 12 weeks, 1.31 {+-} 1.17 versus 2.17 {+-} 0.85 in BNS. The results for vessel wall injury (0.6 {+-} 0.58 for Polyzene-F-coated stents; 0.72 {+-} 0.98 for BNS) and re-endothelialization, (1.16 {+-} 0.43 and 1.23 {+-} 0.54, respectively) were not statistically significant at 12-week follow-up. No thrombus deposition was observed on the stents at either follow-up time point. Conclusion: Nitinol stents with a nanothin Polyzene-F coating successfully decreased in-stent stenosis and vessel wall inflammation compared with BNS. Endothelialization and vessel wall injury were found to be equal. These studies warrant long-term pig studies ({>=}120 days) because 12 weeks may not be sufficient time for complete healing; thereafter, human studies may be warranted.« less

  18. Long-term outcomes of a newly developed hybrid metal stent for EUS-guided biliary drainage (with videos).

    PubMed

    Cho, Dong Hui; Lee, Sang Soo; Oh, Dongwook; Song, Tae Jun; Park, Do Hyun; Seo, Dong Wan; Lee, Sung Koo; Kim, Myung-Hwan

    2017-05-01

    Although fully covered self-expandable metal stents (FCSEMSs) have been commonly used for EUS-guided biliary drainage (EUS-BD), FCSEMS migration is a main limitation of this procedure. In the present study we evaluated the technical and clinical success rates, adverse events, and long-term outcomes of a newly developed hybrid stent that has been customized for EUS-BD. From September 2011 to May 2015, 54 consecutive patients with biliary obstruction were enrolled in this prospective, observational study. These patients were candidates for alternative BD techniques because of failed ERCP. The hybrid metal stent used for EUS-BD in this study was partially covered, had anchoring flaps, and is commercially available in Korea. EUS-guided hepaticogastrostomy (EUS-HGS) was performed in 21 patients and EUS-guided choledochoduodenostomy (EUS-CDS) in 33 patients. The technical and clinical success rates of EUS-BD were 100% (54/54) and 94.4% (51/54), respectively. Immediate adverse events developed after EUS-BD in 9 patients (16.6%; cholangitis in 3, bleeding in 2, self-limited pneumoperitoneum in 3, and abdominal pain in 1). Proximal or distal stent migration was not observed during the follow-up period (median, 148.5 days; IQR, 79.7-244), and the mean stent patency duration was 166.3 days and 329.1 days in the EUS-HGS and EUS-CDS groups, respectively. EUS-BD with the hybrid metal stent is technically feasible and can effectively treat biliary obstruction after failed ERCP. EUS-BD with the hybrid metal stent can reduce stent-related adverse events, especially stent migration. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  19. Covered self-expandable metal stents with an anti-migration system improve patency duration without increased complications compared with uncovered stents for distal biliary obstruction caused by pancreatic carcinoma: a randomized multicenter trial.

    PubMed

    Kitano, Masayuki; Yamashita, Yukitaka; Tanaka, Kiyohito; Konishi, Hideyuki; Yazumi, Shujiro; Nakai, Yoshitaka; Nishiyama, Osamu; Uehara, Hiroyuki; Mitoro, Akira; Sanuki, Tsuyoshi; Takaoka, Makoto; Koshitani, Tatsuya; Arisaka, Yoshifumi; Shiba, Masatsugu; Hoki, Noriyuki; Sato, Hideki; Sasaki, Yuichi; Sato, Masako; Hasegawa, Kazunori; Kawabata, Hideaki; Okabe, Yoshihiro; Mukai, Hidekazu

    2013-11-01

    The requirements of biliary stents used in the palliation of malignant biliary obstruction are a long duration of patency and minimal adverse effects. Covered self-expandable metal stents (SEMSs) have been shown to prevent tumor ingrowth, which is the most frequent complication of uncovered SEMSs. However, because they are prone to migration, the superiority of covered SEMS has yet to be convincingly demonstrated. The aim of this study was to evaluate the superiority of covered over uncovered SEMSs in the palliation of distal biliary obstruction due to unresectable pancreatic carcinoma, using both stent types with relatively low axial force and uncovered flared ends to prevent their migration. From April 2009 to December 2010, 120 patients who were admitted to 22 tertiary-care centers because of distal biliary obstruction from unresectable pancreatic carcinomas were enrolled in this prospective randomized multicenter study. Patients were randomly assigned to receive a covered or uncovered SEMS deployed at the site of the biliary stricture during endoscopic retrograde cholangiopancreatography. Stent patency time, patient survival time, patient survival time without stent dysfunction (time to stent dysfunction or patient death), cause of stent dysfunction (ingrowth, overgrowth, migration, or sludge formation), and serious adverse events were compared between covered and uncovered SEMS groups. Patient survival time in the two groups did not significantly differ (median: 285 and 223 days, respectively; P=0.68). Patient survival time without stent dysfunction was significantly longer in the covered than in the uncovered SEMS group (median: 187 vs. 132 days; P=0.043). Stent patency was also significantly longer in the covered than in the uncovered SEMS group (mean±s.d.: 219.3±159.1 vs. 166.9±124.9 days; P=0.047). Reintervention for stent dysfunction was performed in 14 of 60 patients with covered SEMSs (23%) and in 22 of 60 patients with uncovered SEMSs (37%; P=0

  20. Air cholangiography in endoscopic bilateral stent-in-stent placement of metallic stents for malignant hilar biliary obstruction.

    PubMed

    Lee, Jae Min; Lee, Sang Hyub; Jang, Dong Kee; Chung, Kwang Hyun; Park, Jin Myung; Paik, Woo Hyun; Lee, Jun Kyu; Ryu, Ji Kon; Kim, Yong-Tae

    2016-03-01

    Although endoscopic bilateral stent-in-stent (SIS) placement of self-expandable metallic stents (SEMS) is one of the major palliative treatments for unresectable malignant hilar biliary obstruction, post-endoscopic retrograde cholangiopancreatography (ERCP) cholangitis can occur frequently due to inadequate drainage, especially after contrast injection into the biliary tree. The aim of this study is to evaluate the efficacy and safety of air cholangiography-assisted stenting. This study included 47 patients with malignant hilar biliary obstruction who underwent endoscopic bilateral SEMS placement using the SIS technique. They were divided into two groups, air (n = 23) or iodine contrast (n = 24) cholangiography. We retrospectively compared comprehensive clinical and laboratory data of both groups. There were no significant differences found between the two groups with respect to technical success (87% versus 87.5%, air versus contrast group, respectively), functional success (95% versus 95.2%), 30-day mortality (8.3% versus 8.7%) and stent patency. Post-ERCP adverse events occurred in 5 (21.7%) of the patients in the air group and 8 (33.3%) of the patients in the contrast group. Among these, the rate of cholangitis was significantly lower in the air group (4.8% versus 29.2%, p = 0.048). In multivariate analysis, air cholangiography, technical success and a shorter procedure time were significantly associated with a lower incidence of post-ERCP cholangitis. Air cholangiography-assisted stenting can be a safe and effective method for endoscopic bilateral SIS placement of SEMS in patients with malignant hilar biliary obstruction.

  1. Nasojejunal-stent technique (NJST): A new system to prevent fully covered metal stent migration in the treatment of benign esophageal diseases.

    PubMed

    Hernández Mondragón, Oscar Víctor; Cuellar, Raquel Palos; Murcio Pérez, Enrique

    2018-05-19

    Fully covered self-expandable metal stents (FCSEMS) have been used for the treatment of benign esophageal conditions such as perforation, leaks, and strictures [1]; high clinical success is reported [2]. Different anchoring methods have been described (clips, suturing devices, over-the-scope clips and Shim technique [2]), because of high migration rates (4-36%) [3,4]. However, not all cases are candidates, mostly in "difficult" cases where enteral feeding is needed [5]. We report the use of the nasojejunal-stent technique (NJST) to prevent migration of FCSEMS in three difficult cases. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  2. Estimation and comparison of cumulative incidences of biliary self-expandable metallic stent dysfunction accounting for competing risks.

    PubMed

    Hamada, Tsuyoshi; Nakai, Yousuke; Isayama, Hiroyuki; Togawa, Osamu; Kogure, Hirofumi; Kawakubo, Kazumichi; Tsujino, Takeshi; Sasahira, Naoki; Hirano, Kenji; Yamamoto, Natsuyo; Ito, Yukiko; Sasaki, Takashi; Mizuno, Suguru; Toda, Nobuo; Tada, Minoru; Koike, Kazuhiko

    2014-03-01

    Self-expandable metallic stent (SEMS) placement is widely carried out for distal malignant biliary obstruction, and survival analysis is used to evaluate the cumulative incidences of SEMS dysfunction (e.g. the Kaplan-Meier [KM] method and the log-rank test). However, these statistical methods might be inappropriate in the presence of 'competing risks' (here, death without SEMS dysfunction), which affects the probability of experiencing the event of interest (SEMS dysfunction); that is, SEMS dysfunction can no longer be observed after death. A competing risk analysis has rarely been done in studies on SEMS. We introduced the concept of a competing risk analysis and illustrated its impact on the evaluation of SEMS outcomes using hypothetical and actual data. Our illustrative study included 476 consecutive patients who underwent SEMS placement for unresectable distal malignant biliary obstruction. A significant difference between cumulative incidences of SEMS dysfunction in male and female patients via theKM method (P = 0.044 by the log-rank test) disappeared after applying a competing risk analysis (P = 0.115 by Gray's test). In contrast, although cumulative incidences of SEMS dysfunction via the KM method were similar with and without chemotherapy (P = 0.647 by the log-rank test), cumulative incidence of SEMS dysfunction in the non-chemotherapy group was shown to be significantly lower (P = 0.031 by Gray's test) in a competing risk analysis. Death as a competing risk event needs to be appropriately considered in estimating a cumulative incidence of SEMS dysfunction, otherwise analytical results may be biased. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  3. An Update to Hepatobiliary Stents

    PubMed Central

    Moy, Brian T.; Birk, John W.

    2015-01-01

    Endoscopic stent placement is a common primary management therapy for benign and malignant biliary strictures. However, continuous use of stents is limited by occlusion and migration. Stent technology has evolved significantly over the past two decades to reduce these problems. The purpose of this article is to review current guidelines in managing malignant and benign biliary obstructions, current endoscopic techniques for stent placement, and emerging stent technology. What began as a simple plastic stent technology has evolved significantly to include uncovered, partially covered, and fully covered self-expanding metal stents (SEMS) as well as magnetic, bioabsorbable, drug-eluting, and antireflux stents.1 PMID:26357636

  4. Effect of Covered Metallic Stents Compared With Plastic Stents on Benign Biliary Stricture Resolution

    PubMed Central

    Coté, Gregory A.; Slivka, Adam; Tarnasky, Paul; Mullady, Daniel K.; Elmunzer, B. Joseph; Elta, Grace; Fogel, Evan; Lehman, Glen; McHenry, Lee; Romagnuolo, Joseph; Menon, Shyam; Siddiqui, Uzma D.; Watkins, James; Lynch, Sheryl; Denski, Cheryl; Xu, Huiping; Sherman, Stuart

    2017-01-01

    IMPORTANCE Endoscopic placement of multiple plastic stents in parallel is the first-line treatment for most benign biliary strictures; it is possible that fully covered, self-expandable metallic stents (cSEMS) may require fewer endoscopic retrograde cholangiopancreatography procedures (ERCPs) to achieve resolution. OBJECTIVE To assess whether use of cSEMS is noninferior to plastic stents with respect to stricture resolution. DESIGN, SETTING, AND PARTICIPANTS Multicenter (8 endoscopic referral centers), open-label, parallel, randomized clinical trial involving patients with treatment-naive, benign biliary strictures (N = 112) due to orthotopic liver transplant (n = 73), chronic pancreatitis (n = 35), or postoperative injury (n = 4), who were enrolled between April 2011 and September 2014 (with follow-up ending October 2015). Patients with a bile duct diameter less than 6 mm and those with an intact gallbladder in whom the cystic duct would be overlapped by a cSEMS were excluded. INTERVENTIONS Patients (N = 112) were randomized to receive multiple plastic stents or a single cSEMS, stratified by stricture etiology and with endoscopic reassessment for resolution every 3 months (plastic stents) or every 6 months (cSEMS). Patients were followed up for 12 months after stricture resolution to assess for recurrence. MAIN OUTCOMES AND MEASURES Primary outcome was stricture resolution after no more than 12 months of endoscopic therapy. The sample size was estimated based on the noninferiority of cSEMS to plastic stents, with a noninferiority margin of −15%. RESULTS There were 55 patients in the plastic stent group (mean [SD] age, 57 [11] years; 17 women [31%]) and 57 patients in the cSEMS group (mean [SD] age, 55 [10] years; 19 women [33%]). Compared with plastic stents (41/48, 85.4%), the cSEMS resolution rate was 50 of 54 patients (92.6%), with a rate difference of 7.2% (1-sided 95% CI, −3.0% to ∞; P < .001). Given the prespecified noninferiority margin of −15%, the

  5. A prospective group sequential study evaluating a new type of fully covered self-expandable metal stent for the treatment of benign biliary strictures (with video).

    PubMed

    Poley, Jan-Werner; Cahen, Djuna L; Metselaar, Herold J; van Buuren, Henk R; Kazemier, Geert; van Eijck, Casper H J; Haringsma, Jelle; Kuipers, Ernst J; Bruno, Marco J

    2012-04-01

    Fully-covered self expandable metal stents (fcSEMSs) are an alternative to progressive plastic stenting for the treatment of benign biliary strictures (BBS) with the prospect of a higher treatment efficacy and the need for fewer ERCPs, thereby reducing the burden for patients and possibly costs. Key to this novel treatment is safe stent removal. To investigate the feasibility and safety of stent removal of a fcSEMS with a proximal retrieval lasso: a long wire thread integrated in the proximal ends of the wire mesh that hangs freely in the stent lumen. Pulling it enables gradual removal of the stent inside-out. A secondary aim was success of stricture resolution. Non-randomized, prospective follow-up study with 3 sequential cohorts of 8 patients with BBS. Academic tertiary referral center. Eligible patients had strictures either postsurgical (post-cholecystectomy (LCx) or liver transplantation (OLT)), due to chronic pancreatitis (CP), or papillary stenosis (PF). Strictures had to be located at least 2 cm below the liver hilum. All patients had one plastic stent in situ across the stricture and had not undergone previous treatment with either multiple plastic stents or fcSEMS. The first cohort of patients underwent stent placement for 2 months, followed by 3 months if the stricture had not resolved. The second and third cohort started with 3 months and 4 months, respectively, both followed by another 4 months if indicated. Treatment success was defined by stricture resolution at cholangiography, the ability to pass an inflated extraction balloon and clinical follow-up (at least 6 months). safety of stent removal. Secondary outcomes were complications and successful stricture resolution. A total of 23 patients (11 female; 20-67 yrs) were eligible for final analysis. One patient developed a malignant neuroendocrine tumor in the setting of CP. Strictures were caused by CP (13), OLT (6), LCx (3) and PF (1). In total 39 fcSEMS were placed and removed. Removals were easy

  6. Two-year Clinical Outcomes Post Implantation of Epic™ Self-Expanding Nitinol Stents for the Aortoiliac Occlusive Disease in Patients with Peripheral Arterial Disease

    PubMed Central

    Tsujimura, Takuya; Iida, Osamu; Fujita, Masashi; Masuda, Masaharu; Okamoto, Shin; Ishihara, Takayuki; Nanto, Kiyonori; Kanda, Takashi; Okuno, Shota; Matsuda, Yasuhiro; Fujihara, Masahiko; Yokoi, Yoshiaki; Mano, Toshiaki

    2018-01-01

    Aim: We investigated 2-year clinical outcomes after implantaton of Epic™ self-expanding nitinol stents for patients with peripheral artery disease (PAD) due to the aortoiliac occlusive disease (AIOD). Methods: This study was a multicenter and retrospective study. From February 2013 through October 2014, 292 lesions (chronic total occlusion, 21%; TASC II C/D, 35%) in 217 consecutive patients (74 ± 8 years; male, 81%; diabetes mellitus, 47%; dialysis, 21%; critical limb ischemia, 29%) who had undergone endovascular therapy (EVT) with Epic™ self-expanding nitinol stents for PAD with AIOD were analyzed. The primary endpoints were 2-year primary patency and target lesion revascularization (TLR)-free rate. The primary patency and freedom from TLR were determined by Kaplan–Meier analysis. Additionally, predictors for loss of patency were estimated by Cox proportional hazard model. Results: The mean follow-up duration was 19.1 ± 8.5 months. Primary patency was 87.3% at 2 years. Freedom from TLR rate was 94.1% at 2 years. Multivariate analysis revealed that the presence of diabetes mellitus was associated with a loss of patency. Conclusion: The Epic™ self-expanding nitinol stent was demonstrated to be safe and effectivene for AIOD when tested for two years in patients with PAD. PMID:28978866

  7. Fully-covered metal stents with endoscopic suturing vs. partially-covered metal stents for benign upper gastrointestinal diseases: a comparative study

    PubMed Central

    Ngamruengphong, Saowanee; Sharaiha, Reem; Sethi, Amrita; Siddiqui, Ali; DiMaio, Christopher J.; Gonzalez, Susana; Rogart, Jason; Jagroop, Sophia; Widmer, Jessica; Im, Jennifer; Hasan, Raza Abbas; Laique, Sobia; Gonda, Tamas; Poneros, John; Desai, Amit; Wong, Katherine; Villgran, Vipin; Brewer Gutierrez, Olaya; Bukhari, Majidah; Chen, Yen-I; Hernaez, Ruben; Hanada, Yuri; Sanaei, Omid; Agarwal, Amol; Kalloo, Anthony N.; Kumbhari, Vivek; Singh, Vikesh; Khashab, Mouen A.

    2018-01-01

    Background and study aims  Self-expandable metallic stents (SEMS) have been increasingly used in benign conditions (e. g. strictures, fistulas, leaks, and perforations). Fully covered SEMS (FSEMS) were introduced to avoid undesirable consequences of partially covered SEMS (PSEMS), but come with higher risk of stent migration. Endoscopic suturing (ES) for stent fixation has been shown to reduce migration of FSEMS. Our aim was to compare the outcomes of FSEMS with ES (FS/ES) versus PSEMS in patients with benign upper gastrointestinal conditions. Patients and methods  We retrospectively identified all patients who underwent stent placement for benign gastrointestinal conditions at seven US tertiary-care centers. Patients were divided into two groups: FSEMS with ES (FS/ES group) and PSEMS (PSEMS group). Clinical outcomes between the two groups were compared. Results  A total of 74 (FS/ES 46, PSEMS 28) patients were included. On multivariable analysis, there was no significant difference in rate of stent migration between FS/ES (43 %) and PSEMS (15 %) (adjusted odds ratio 0.56; 95 % CI 0.15 – 2.00). Clinical success was similar [68 % vs. 64 %; P  = 0.81]. Rate of adverse events (AEs) was higher in PSEMS group [13 (46 %) vs. 10 (21 %); P  = 0.03). Difficult stent removal was higher in the PSEMS group (n = 5;17 %) vs. 0 % in the FS/ES group; P  = 0.005. Conclusions  The proportion of stent migration of FS/ES and PSEMS are similar. Rates of other stent-related AEs were higher in the PSEMS group. PSEMS was associated with tissue ingrowth or overgrowth leading to difficult stent removal, and secondary stricture formation. Thus, FSEMS with ES for stent fixation may be the preferred modality over PSEMS for the treatment of benign upper gastrointestinal conditions. PMID:29404384

  8. Temporary endoscopic metallic stent for idiopathic esophageal achalasia.

    PubMed

    Coppola, Franco; Gaia, Silvia; Rolle, Emanuela; Recchia, Serafino

    2014-02-01

    Idiopathic achalasia is a motor disorder of the esophagus of unknown etiology caused by loss of motor neurons determining an altered motility. It may determine severe symptoms such as progressive dysphagia, regurgitations, and pulmonary aspirations. Many therapeutic options may be offered to patients with achalasia, from surgery to endoscopic treatments such as pneumatic dilation, botulinum injection, peroral endoscopic myotomy, or endoscopic stenting. Recently, temporary placement of a stent was proposed by Cheng as therapy for achalasia disorders, whereas no Western authors have dealt with it up to date. The present study reports our preliminary experience in 7 patients with achalasia treated with a temporary stent. Partially covered self-expanding metallic stents (Micro-Tech, Nanjin, China) 80 mm long and 30 mm wide were placed under fluoroscopic control and removed after 6 days. Clinical follow-up was scheduled to check endoscopic success, symptoms release, and complications. The placement and the removal of the stents were obtained in all patients without complications. Mean clinical follow-up was 19 months. Five out of 7 patients referred total symptoms release and 2 experienced significant improvement of dysphagia. The procedure was not time consuming and was safe; no mild or severe complications were registered. In conclusion, our results may suggest a possible safe and effective endoscopic alternative treatment in patients with achalasia; however, further larger studies are necessary to confirm these promising, but very preliminary, data.

  9. Mechanisms of Biliary Plastic Stent Occlusion and Efforts at Prevention

    PubMed Central

    Kwon, Chang-Il; Lehman, Glen A.

    2016-01-01

    Biliary stenting via endoscopic retrograde cholangiopancreatography has greatly improved the quality of patient care over the last 30 years. Plastic stent occlusion limits the life span of such stents. Attempts to improve plastic stent patency duration have mostly failed. Metal stents (self-expandable metal stents [SEMSs]) have therefore replaced plastic stents, especially for malignant biliary strictures. SEMS are at least 10 times more expensive than plastic stents. In this focused review, we will discuss basic mechanisms of plastic stent occlusion, along with a systematic summary of previous efforts and related studies to improve stent patency and potential new techniques to overcome existing limitations. PMID:27000422

  10. Treatment of malignant gastric outlet obstruction with endoscopically placed self-expandable metal stents

    PubMed Central

    Gaidos, Jill KJ; Draganov, Peter V

    2009-01-01

    Malignant gastroduodenal obstruction can occur in up to 20% of patients with primary pancreatic, gastric or duodenal carcinomas. Presenting symptoms include nausea, vomiting, abdominal distention, pain and decreased oral intake which can lead to dehydration, malnutrition, and poor quality of life. Endoscopic stent placement has become the primary therapeutic modality because it is safe, minimally invasive, and a cost-effective option for palliation. Stents can be successfully deployed in the majority of patients. Stent placement appears to lead to a shorter time to symptomatic improvement, shorter time to resumption of an oral diet, and shorter hospital stays as compared with surgical options. Recurrence of the obstructive symptoms resulting from stent occlusion, due to tumor ingrowth or overgrowth, can be successfully treated with repeat endoscopic stent placement in the majority of the cases. Both endoscopic stenting and surgical bypass are considered palliative treatments and, to date, no improvement in survival with either modality has been demonstrated. A tailored therapeutic approach, taking into consideration patient preferences and involving a multidisciplinary team including the therapeutic endoscopist, surgeon, medical oncologist, radiation therapist, and interventional radiologist, should be considered in all cases. PMID:19764086

  11. Role of stents and laser therapy in biliary strictures

    NASA Astrophysics Data System (ADS)

    Chennupati, Raja S.; Trowers, Eugene A.

    2001-05-01

    The most frequent primary cancers causing malignant obstructive jaundice were pancreatic cancer (57%), hilar biliary cancer (19% including metastatic disease), nonhilar biliary cancer (14%) and papillary cancer (10%). Endoscopic stenting has widely replaced palliative surgery for malignant biliary obstruction because of its lower risk and cost. Self-expandable metal stents are the preferred mode of palliation for hilar malignancies. Plastic stents have a major role in benign biliary strictures. Major complications and disadvantages associated with metallic stents include high cost, cholangitis. malposition, migration, unextractability, and breakage of the stents, pancreatitis and stent dysfunction. Dysfunction due to tumor ingrowth can be relieved by thermal methods (argon plasma coagulator therapy). We present a concise review of the efficacy of metallic stents for palliation of malignant strictures.

  12. Percutaneous Transhepatic Biliary Stenting with Uncovered Self-Expandable Metallic Stents in Patients with Malignant Biliary Obstruction - Efficacy and Survival Analysis.

    PubMed

    Pranculis, Andrius; Kievišas, Mantas; Kievišienė, Lina; Vaičius, Artūras; Vanagas, Tomas; Kaupas, Rytis Stasys; Dambrauskas, Žilvinas

    2017-01-01

    The aim of this study was to assess short- and long-term outcomes of malignant biliary obstruction (MBO) treatment by percutaneous transhepatic biliary stenting (PTBS) with uncovered selfexpandable metallic stents (SEMS), and to identify predictors of survival. A nine-year, single-centre study from a prospectively collected database included 222 patients with inoperable MBO treated by PTBS with uncovered nitinol SEMS. Technical and clinical success rates were 95.9% and 82.4%, respectively. The total rate of postprocedural complications was 14.4%. The mean durations of the primary and secondary stent patency were 114.7±15.1 and 146.4±21.2 days, respectively. The 30-day mortality rate was 15.3% with no procedure-related deaths. The mean estimated length of survival was 143.3±20.6 days. Independent predictors increasing the risk of death included higher than 115 μmol/L serum bilirubin 2-5 days after biliary stenting (HR 3.274, P =0.019), distal (non-hilar) obstruction of the bile ducts (HR 3.711, P =0.008), Bismuth-Corlette type IV stricture (HR 2.082, P =0.008), obstruction due to gallbladder cancer (HR 31.029, P =0.012) and only partial drainage of liver parenchyma (HR 4.158, P =0.040). PTBS with uncovered SEMS is an effective and safe method for palliative treatment of MBO. Serum bilirubin higher than 115 μmol/L 2-5 days after the procedure has a significant negative impact on patients' survival. Lower survival is also determined by distal bile duct obstruction, Bismuth- Corlette type IV stricture, biliary obstruction caused by gallbladder cancer and when only partial liver drainage is applied.

  13. Bilateral metal stents for hilar biliary obstruction using a 6Fr delivery system: outcomes following bilateral and side-by-side stent deployment.

    PubMed

    Law, Ryan; Baron, Todd H

    2013-09-01

    Controversy exists on optimal endoscopic management for palliation of malignant hilar obstruction, with advocates for metal "side-by-side" (SBS) and "stent-in-stent" (SIS) techniques. We sought to evaluate the technical feasibility, efficacy, and outcomes of bilateral biliary self-expanding metal stents (SEMS) for treatment of malignant hilar obstruction using a stent with a 6Fr delivery system. This was a single-center, retrospective review of all patients who underwent bilateral placement of Zilver® biliary SEMS for malignant hilar obstruction from January 2010 to August 2012. Patients underwent endoscopic retrograde cholangiopancreatography with placement of stents using either the SIS or SBS stent techniques. Twenty-four patients (19 men, mean age 63 years) underwent bilateral stenting for malignant hilar obstruction during the study period. Seventeen and seven patients underwent the SBS and SIS technique, respectively. Cholangiocarcinoma (n=14) was the most common cause of hilar obstruction. Initial technical success was achieved in 24/24 (100%) of patients; however, 12 (50%) patients required re-intervention during the study period (median 98 days). Comparison of the SBS and SIS groups revealed no statistical difference with respect to need for re-intervention (P=0.31), successful re-intervention (P=0.60), or procedural length (P=0.89). Use of bilateral Zilver® SEMS in either the SBS or SIS configuration is safe, technically feasible, and effective for drainage of malignant hilar obstruction; however, duration of stent patency and procedure-free survival remain variable.

  14. Bronchobiliary Fistula Treated by Self-expanding ePTFE-Covered Nitinol Stent-Graft

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gandini, Roberto; Konda, Daniel; Tisone, Giuseppe

    A 71-year-old man, who had undergone right hepatectomy extended to the caudate lobe with terminolateral Roux-en-Y left hepatojejunostomy for a Klatskin tumor, developed bilioptysis 3 weeks postoperatively due to bronchobiliary fistula. Percutaneous transhepatic cholangiography revealed a non-dilated biliary system with contrast medium extravasation to the right subphrenic space through a resected anomalous right posterior segmental duct. After initial unsuccessful internal-external biliary drainage, the fistula was sealed with a VIATORR covered self-expanding nitinol stent-graft placed with its distal uncovered region in the hepatojejunal anastomosis and the proximal ePTFE-lined region in the left hepatic duct. A 10-month follow-up revealed no recurrence ofmore » bilioptysis and confirmed the complete exclusion of the bronchobiliary fistula.« less

  15. Covered metal stent or multiple plastic stents for refractory pancreatic ductal strictures in chronic pancreatitis: a systematic review.

    PubMed

    Shen, Yonghua; Liu, Mingdong; Chen, Min; Li, Yunhong; Lu, Ying; Zou, Xiaoping

    2014-01-01

    Refractory chronic pancreatitis has been proposed as a challenge for endoscopists following routine single plastic stenting. However, data on the efficacy and safety of further endoscopic stenting are still controversial. The current systematic review aimed to assess the efficacy and safety of placement of fully covered self-expandable metal stent (FCSEMS) and multiple plastic stents. Databases including MEDLINE, EMBASE, the Cochrane Library, CBM, CNKI, VIP, and WANFANG Database were used to search relevant trials. Published studies were assessed by using well-defined inclusion and exclusion criteria. The process was independently performed by two investigators. A total of 5 studies provided data of 80 patients. Forest plots and publication bias were not carried out because few studies were relevant and screened studies were all case series. The technical success rate was 100% both in placement of FCSEMS and multiple plastic stents. The functional success rate after placement of FCSEMS was 100%, followed by multiple plastic stents (94.7%). Complications occurred 26.2% after FCSEMS placement, which was not described in detail in multiple plastic stents. The stent migration rate was 8.2% for FCSEMS and 10.5% for multiple plastic stents. Reintervention rate was 9.8% for FCSEMS and 15.8% for multiple plastic stents. Pain improvement rate was 85.2% for FCSEMS and 84.2% for multiple plastic stents. FCSEMS appeared to be no significant difference with multiple plastic stents in treatment of refractory chronic pancreatitis. We need to develop more investigations. Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.

  16. Two-year Clinical Outcomes Post Implantation of EpicTM Self-Expanding Nitinol Stents for the Aortoiliac Occlusive Disease in Patients with Peripheral Arterial Disease.

    PubMed

    Tsujimura, Takuya; Iida, Osamu; Fujita, Masashi; Masuda, Masaharu; Okamoto, Shin; Ishihara, Takayuki; Nanto, Kiyonori; Kanda, Takashi; Okuno, Shota; Matsuda, Yasuhiro; Fujihara, Masahiko; Yokoi, Yoshiaki; Mano, Toshiaki

    2018-04-01

    We investigated 2-year clinical outcomes after implantaton of Epic TM self-expanding nitinol stents for patients with peripheral artery disease (PAD) due to the aortoiliac occlusive disease (AIOD). This study was a multicenter and retrospective study. From February 2013 through October 2014, 292 lesions (chronic total occlusion, 21%; TASC Ⅱ C/D, 35%) in 217 consecutive patients (74±8 years; male, 81%; diabetes mellitus, 47%; dialysis, 21%; critical limb ischemia, 29%) who had undergone endovascular therapy (EVT) with Epic TM self-expanding nitinol stents for PAD with AIOD were analyzed. The primary endpoints were 2-year primary patency and target lesion revascularization (TLR)-free rate. The primary patency and freedom from TLR were determined by Kaplan-Meier analysis. Additionally, predictors for loss of patency were estimated by Cox proportional hazard model. The mean follow-up duration was 19.1±8.5 months. Primary patency was 87.3% at 2 years. Freedom from TLR rate was 94.1% at 2 years. Multivariate analysis revealed that the presence of diabetes mellitus was associated with a loss of patency. The Epic TM self-expanding nitinol stent was demonstrated to be safe and effectivene for AIOD when tested for two years in patients with PAD.

  17. Efficacy and safety of limited endoscopic sphincterotomy before self-expandable metal stent insertion for malignant biliary obstruction.

    PubMed

    Nam, Hyeong Seok; Kang, Dae Hwan; Kim, Hyung Wook; Choi, Cheol Woong; Park, Su Bum; Kim, Su Jin; Ryu, Dae Gon

    2017-03-07

    To evaluate the safety and efficacy of limited endoscopic sphincterotomy (ES) before placement of self-expandable metal stent (SEMS). This was a retrospective analysis of 244 consecutive patients with unresectable malignant biliary obstruction, who underwent placement of SEMSs following limited ES from December 2008 to February 2015. The diagnosis of malignant biliary obstruction and assessment of patient eligibility for the study was established by a combination of clinical findings, laboratory investigations, imaging and pathological results. All patients were monitored in the hospital for at least 24 h following endoscopic retrograde cholangio pancreatography (ERCP). The incidence of immediate or early post-ERCP complications such as post-ERCP pancreatitis (PEP) and bleeding related to limited ES were considered as primary outcomes. Also, characteristics and complications according to the cancer type were classified. Among the 244 patients included, the underlying diagnosis was cholangiocarcinoma in 118 patients, pancreatic cancer in 79, and non-pancreatic or non-biliary malignancies in the remaining 47 patients. Early post-ERCP complications occurred in 9 patients (3.7%), with PEP in 7 patients (2.9%; mild, 6; moderate, 1) and mild bleeding in 2 patients (0.8%). There was no significant association between the incidence of post-ERCP complications and the type of malignancy (cholangiocarcinoma vs pancreatic cancer vs others, P = 0.696) or the type of SEMS used (uncovered vs covered, P = 1.000). Patients who had more than one SEMS placed at the first instance were at a significantly higher risk of post-ERCP complications (one SEMS vs two SEMS, P = 0.031). No other factors were predictive of post-ERCP complications. Limited ES is feasible and safe, and effectively facilitates the placement of SEMS, without any significant risk of PEP or severe bleeding.

  18. Efficacy and safety of limited endoscopic sphincterotomy before self-expandable metal stent insertion for malignant biliary obstruction

    PubMed Central

    Nam, Hyeong Seok; Kang, Dae Hwan; Kim, Hyung Wook; Choi, Cheol Woong; Park, Su Bum; Kim, Su Jin; Ryu, Dae Gon

    2017-01-01

    AIM To evaluate the safety and efficacy of limited endoscopic sphincterotomy (ES) before placement of self-expandable metal stent (SEMS). METHODS This was a retrospective analysis of 244 consecutive patients with unresectable malignant biliary obstruction, who underwent placement of SEMSs following limited ES from December 2008 to February 2015. The diagnosis of malignant biliary obstruction and assessment of patient eligibility for the study was established by a combination of clinical findings, laboratory investigations, imaging and pathological results. All patients were monitored in the hospital for at least 24 h following endoscopic retrograde cholangio pancreatography (ERCP). The incidence of immediate or early post-ERCP complications such as post-ERCP pancreatitis (PEP) and bleeding related to limited ES were considered as primary outcomes. Also, characteristics and complications according to the cancer type were classified. RESULTS Among the 244 patients included, the underlying diagnosis was cholangiocarcinoma in 118 patients, pancreatic cancer in 79, and non-pancreatic or non-biliary malignancies in the remaining 47 patients. Early post-ERCP complications occurred in 9 patients (3.7%), with PEP in 7 patients (2.9%; mild, 6; moderate, 1) and mild bleeding in 2 patients (0.8%). There was no significant association between the incidence of post-ERCP complications and the type of malignancy (cholangiocarcinoma vs pancreatic cancer vs others, P = 0.696) or the type of SEMS used (uncovered vs covered, P = 1.000). Patients who had more than one SEMS placed at the first instance were at a significantly higher risk of post-ERCP complications (one SEMS vs two SEMS, P = 0.031). No other factors were predictive of post-ERCP complications. CONCLUSION Limited ES is feasible and safe, and effectively facilitates the placement of SEMS, without any significant risk of PEP or severe bleeding. PMID:28321164

  19. Novel antireflux covered metal stent for recurrent occlusion of biliary metal stents: a pilot study.

    PubMed

    Hamada, Tsuyoshi; Isayama, Hiroyuki; Nakai, Yousuke; Kogure, Hirofumi; Togawa, Osamu; Kawakubo, Kazumichi; Yamamoto, Natsuyo; Ito, Yukiko; Sasaki, Takashi; Tsujino, Takeshi; Sasahira, Naoki; Hirano, Kenji; Tada, Minoru; Koike, Kazuhiko

    2014-03-01

    Feasibility of antireflux metal stent (ARMS), designed to prevent duodenobiliary reflux, was reported in patients with distal malignant biliary obstruction. In this prospective pilot study, we aimed to evaluate a newly designed ARMS as a reintervention for self-expandable metallic stent (SEMS) occlusion believed to be caused by duodenobiliary reflux. Patients with non-resectable distal malignant biliary obstruction were included in whom a prior SEMS was occluded as a result of sludge or food impaction between March 2010 and January 2012 at two Japanese tertiary referral centers. The occluded SEMS were endoscopically removed, if possible, and subsequently replaced by a newly designed ARMS. We evaluated the technical success rate and complications of ARMS and compared the time to occlusion of ARMS with that of prior SEMS. A total of 13 patients were included. ARMS was successfully placed in all patients in a single procedure. No procedure-related complications were identified. ARMS occlusion occurred in two patients (15%), the causes of which were sludge in one patient and unknown in the other. ARMS migration occurred in four patients (31%). ARMS patency time was significantly longer than that of prior SEMS (median, not available vs 58 days; P = 0.039). This newly designed ARMS is a technically feasible, safe, and effective reintervention for SEMS occlusion as a result of sludge or food impaction. An anti-migration mechanism to improve the outcomes of ARMS should be considered. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  20. A systematic review and meta-analysis of randomized trials and prospective studies comparing covered and bare self-expandable metal stents for the treatment of malignant obstruction in the digestive tract.

    PubMed

    Yang, Zhiping; Wu, Qiong; Wang, Fang; Ye, Xiaofei; Qi, Xingshun; Fan, Daiming

    2013-01-01

    Self-expandable metal stents (SEMS) are widely used for the palliative treatment of malignant gastrointestinal obstruction. Our aim was to evaluate the evidence comparing covered and bare SEMS in the digestive tract using meta-analytical techniques. A literature search was performed using PubMed, Cochrane Library, and Embase databases for comparative studies assessing the two types of stents. The primary outcomes of interest were stent patency and patient survival; second outcomes included technical success, clinical success, tumor ingrowth, tumor overgrowth, and stent migration. A random-effects model was conducted. Pooled analysis was done separately based on the different segments of the digestive tract. Eleven studies (8 randomized controlled trials and 3 prospective cohort studies) including a total of 1376 patients were identified. Covered SEMS were equivalent to bare SEMS in terms of technical success, clinical success, stent patency (gastroduodenal obstruction: HR =0.87, 95% CI 0.53-1.42; colorectal obstruction: HR =0.89, 95% CI 0.18-4.45; biliary obstruction: HR =0.73, 95% CI 0.41-1.32) and survival rates (esophageal obstruction: HR =1.80, 95% CI 0.73-4.44; gastroduodenal obstruction: HR =0.83, 95% CI 0.55-1.26; biliary obstruction: HR =0.99, 95% CI 0.77-1.28), although bare stents were more prone to tumor ingrowth (esophageal obstruction: RR =0.10, 95% CI 0.01-0.77; gastroduodenal obstruction: RR =0.12, 95% CI 0.03-0.55; colorectal obstruction: RR =0.21, 95% CI 0.06-0.70; biliary obstruction: RR =0.21, 95% CI 0.06-0.69), whereas covered stents had the higher risk of stent migration (gastroduodenal obstruction: RR =5.01, 95% CI 1.53-16.43; colorectal obstruction: RR =11.70, 95% CI 2.84-48.27; biliary obstruction: RR =8.11, 95% CI 1.47-44.76) and tumor overgrowth (biliary obstruction: RR =2.03, 95% CI 1.08-3.78). Both covered and bare SEMS are comparable in efficacy for the palliative treatment of malignant obstruction in the digestive tract. Each type of

  1. Partially covered versus uncovered self-expandable nitinol stents with anti-migration properties for the palliation of malignant distal biliary obstruction: A randomized controlled trial.

    PubMed

    Yang, Min Jae; Kim, Jin Hong; Yoo, Byung Moo; Hwang, Jae Chul; Yoo, Jun Hwan; Lee, Ki Seong; Kang, Joon Koo; Kim, Soon Sun; Lim, Sun Gyo; Shin, Sung Jae; Cheong, Jae Youn; Lee, Kee Myung; Lee, Kwang Jae; Cho, Sung Won

    2015-01-01

    Covered self-expandable metal stents (SEMSs) are increasingly used as alternatives to uncovered SEMSs for the palliation of inoperable malignant distal biliary obstruction to counteract tumor ingrowth. We aimed to compare the outcomes of partially covered and uncovered SEMSs with identical mesh structures and anti-migration properties, such as low axial force and flared ends. One hundred and three patients who were diagnosed with inoperable malignant distal biliary obstruction between January 2006 and August 2013 were randomly assigned to either the partially covered (n = 51) or uncovered (n = 52) SEMS group. There were no significant differences in the cumulative stent patency, overall patient survival, stent dysfunction-free survival and overall adverse events, including pancreatitis and cholecystitis, between the two groups. Compared to the uncovered group, stent migration (5.9% vs. 0%, p = 0.118) and tumor overgrowth (7.8% vs. 1.9%, p = 0.205) were non-significantly more frequent in the partially covered group, whereas tumor ingrowth showed a significantly higher incidence in the uncovered group (5.9% vs. 19.2%, p = 0.041). Stent migration in the partially covered group occurred only in patients with short stenosis of the utmost distal bile duct (two in ampullary cancer, one in bile duct cancer), and did not occur in any patients with pancreatic cancer. For the palliation of malignant distal biliary obstruction, endoscopic placement of partially covered SEMSs with anti-migration designs and identical mesh structures to uncovered SEMSs failed to prolong cumulative stent patency or reduce stent migration.

  2. Plastic or metal stents for benign extrahepatic biliary strictures: a systematic review

    PubMed Central

    2009-01-01

    Background Benign biliary strictures may be a consequence of surgical procedures, chronic pancreatitis or iatrogenic injuries to the ampulla. Stents are increasingly being used for this indication, however it is not completely clear which stent type should be preferred. Methods A systematic review on stent placement for benign extrahepatic biliary strictures was performed after searching PubMed and EMBASE databases. Data were pooled and evaluated for technical success, clinical success and complications. Results In total, 47 studies (1116 patients) on outcome of stent placement were identified. No randomized controlled trials (RCTs), one non-randomized comparative studies and 46 case series were found. Technical success was 98,9% for uncovered self-expandable metal stents (uSEMS), 94,8% for single plastic stents and 94,0% for multiple plastic stents. Overall clinical success rate was highest for placement of multiple plastic stents (94,3%) followed by uSEMS (79,5%) and single plastic stents (59.6%). Complications occurred more frequently with uSEMS (39.5%) compared with single plastic stents (36.0%) and multiple plastic stents (20,3%). Conclusion Based on clinical success and risk of complications, placement of multiple plastic stents is currently the best choice. The evolving role of cSEMS placement as a more patient friendly and cost effective treatment for benign biliary strictures needs further elucidation. There is a need for RCTs comparing different stent types for this indication. PMID:20017920

  3. Bleeding after expandable nitinol stent placement in patients with esophageal and upper gastrointestinal obstruction: incidence, management, and predictors.

    PubMed

    Oh, Se Jin; Song, Ho-Young; Nam, Deok Ho; Ko, Heung Kyu; Park, Jung-Hoon; Na, Han Kyu; Lee, Jong Jin; Kang, Min Kyoung

    2014-11-01

    Placement of self-expandable nitinol stents is useful for the treatment of esophageal and upper gastrointestinal (GI) obstruction. However, complications such as stent migration, tumor overgrowth, and bleeding occur. Although stent migration and tumor overgrowth are well documented in previous studies, the occurrence of bleeding has not been fully evaluated. To evaluate the incidence, management strategies, and predictors of bleeding after placement of self-expandable nitinol stents in patients with esophageal and upper GI obstruction. We retrospectively reviewed the medical records and results of computed tomography and endoscopy of 1485 consecutive patients with esophageal and upper GI obstructions who underwent fluoroscopically guided stent placement. Bleeding occurred in 25 of 1485 (1.7%) patients 0 to 348 days after stent placement. Early stent-related bleeding occurred in 10 patients (40%) and angiographic embolization was used for 5/10. Late bleeding occurred in 15 patients (60%) and endoscopic hemostasis was used for 7/15. Twenty-two of 25 (88%) patients with bleeding had received prior radiotherapy and/or chemotherapy. Bleeding is a rare complication after placement of expandable nitinol stents in patients with esophageal and upper GI obstruction, but patients with early bleeding may require embolization for control. Care must be exercised on placing stents in patients who have received prior radiotherapy or chemotherapy. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  4. Fully Covered Metallic Stents for the Treatment of Benign Airway Stenosis

    PubMed Central

    Ocak, Sebahat; Gourdin, Maximilien; d'Odémont, Jean-Paul

    2016-01-01

    Introduction. We herein report our experience with new fully covered self-expanding metallic stents in the setting of inoperable recurrent benign tracheobronchial stenosis. Methods. Between May 2010 and July 2014, 21 Micro-Tech® FC-SEMS (Nanjing Co., Republic of Korea) were placed in our hospital in 16 patients for inoperable, recurrent (after dilatation), and symptomatic benign airway stenosis. Their medical files were retrospectively reviewed in December 2014, with focus on stent's tolerance and durability data. Results. Twenty-one stents were inserted: 13 for posttransplant left main bronchus anastomotic stricture, seven for postintubation tracheal stenosis, and one for postlobectomy anastomotic stricture. Positioning was easy for all of them. Stents were in place for a mean duration of 282 days. The most common complications were granulation tissue development (35%), migration (30%), and sputum retention (15%). Fifty-five % of the stents (11/20) had to be removed because of various complications, without difficulty for all of them. None of the patients had life-threatening complications. Conclusion. Micro-Tech FC-SEMS were easy to position and to remove. While the rate of complications requiring stent removal was significant, no life-threatening complication occurred. Further studies are needed to better define their efficacy and safety in the treatment of benign airway disease. PMID:27777507

  5. Fully Covered Metallic Stents for the Treatment of Benign Airway Stenosis.

    PubMed

    Dahlqvist, Caroline; Ocak, Sebahat; Gourdin, Maximilien; Dincq, Anne Sophie; Putz, Laurie; d'Odémont, Jean-Paul

    2016-01-01

    Introduction. We herein report our experience with new fully covered self-expanding metallic stents in the setting of inoperable recurrent benign tracheobronchial stenosis. Methods. Between May 2010 and July 2014, 21 Micro-Tech® FC-SEMS (Nanjing Co., Republic of Korea) were placed in our hospital in 16 patients for inoperable, recurrent (after dilatation), and symptomatic benign airway stenosis. Their medical files were retrospectively reviewed in December 2014, with focus on stent's tolerance and durability data. Results. Twenty-one stents were inserted: 13 for posttransplant left main bronchus anastomotic stricture, seven for postintubation tracheal stenosis, and one for postlobectomy anastomotic stricture. Positioning was easy for all of them. Stents were in place for a mean duration of 282 days. The most common complications were granulation tissue development (35%), migration (30%), and sputum retention (15%). Fifty-five % of the stents (11/20) had to be removed because of various complications, without difficulty for all of them. None of the patients had life-threatening complications. Conclusion. Micro-Tech FC-SEMS were easy to position and to remove. While the rate of complications requiring stent removal was significant, no life-threatening complication occurred. Further studies are needed to better define their efficacy and safety in the treatment of benign airway disease.

  6. Metal or plastic stents for preoperative biliary drainage in resectable pancreatic cancer.

    PubMed

    Tol, J A M G; van Hooft, J E; Timmer, R; Kubben, F J G M; van der Harst, E; de Hingh, I H J T; Vleggaar, F P; Molenaar, I Q; Keulemans, Y C A; Boerma, D; Bruno, M J; Schoon, E J; van der Gaag, N A; Besselink, M G H; Fockens, P; van Gulik, T M; Rauws, E A J; Busch, O R C; Gouma, D J

    2016-12-01

    In pancreatic cancer, preoperative biliary drainage (PBD) increases complications compared with surgery without PBD, demonstrated by a recent randomised controlled trial (RCT). This outcome might be related to the plastic endoprosthesis used. Metal stents may reduce the PBD-related complications risk. A prospective multicentre cohort study was performed including patients with obstructive jaundice due to pancreatic cancer, scheduled to undergo PBD before surgery. This cohort was added to the earlier RCT (ISRCTN31939699). The RCT protocol was adhered to, except PBD was performed with a fully covered self-expandable metal stent (FCSEMS). This FCSEMS cohort was compared with the RCT's plastic stent cohort. PBD-related complications were the primary outcome. Three-group comparison of overall complications including early surgery patients was performed. 53 patients underwent PBD with FCSEMS compared with 102 patients treated with plastic stents. Patients' characteristics did not differ. PBD-related complication rates were 24% in the FCSEMS group vs 46% in the plastic stent group (relative risk of plastic stent use 1.9, 95% CI 1.1 to 3.2, p=0.011). Stent-related complications (occlusion and exchange) were 6% vs 31%. Surgical complications did not differ, 40% vs 47%. Overall complication rates for the FCSEMS, plastic stent and early surgery groups were 51% vs 74% vs 39%. For PBD in pancreatic cancer, FCSEMS yield a better outcome compared with plastic stents. Although early surgery without PBD remains the treatment of choice, FCSEMS should be preferred over plastic stents whenever PBD is indicated. Dutch Trial Registry (NTR3142). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  7. An Efficient Finite Element Framework to Assess Flexibility Performances of SMA Self-Expandable Carotid Artery Stents

    PubMed Central

    Ferraro, Mauro; Auricchio, Ferdinando; Boatti, Elisa; Scalet, Giulia; Conti, Michele; Morganti, Simone; Reali, Alessandro

    2015-01-01

    Computer-based simulations are nowadays widely exploited for the prediction of the mechanical behavior of different biomedical devices. In this aspect, structural finite element analyses (FEA) are currently the preferred computational tool to evaluate the stent response under bending. This work aims at developing a computational framework based on linear and higher order FEA to evaluate the flexibility of self-expandable carotid artery stents. In particular, numerical simulations involving large deformations and inelastic shape memory alloy constitutive modeling are performed, and the results suggest that the employment of higher order FEA allows accurately representing the computational domain and getting a better approximation of the solution with a widely-reduced number of degrees of freedom with respect to linear FEA. Moreover, when buckling phenomena occur, higher order FEA presents a superior capability of reproducing the nonlinear local effects related to buckling phenomena. PMID:26184329

  8. Long-Term Primary Patency Rate After Nitinol Self-Expandable Stents Implantation in Long, Totally Occluded Femoropopliteal (TASC II C & D) Lesions.

    PubMed

    Elmahdy, Mahmoud Farouk; Buonamici, Piergiovanni; Trapani, Maurizio; Valenti, Renato; Migliorini, Angela; Parodi, Guido; Antoniucci, David

    2017-06-01

    Endovascular therapy for long femoropopliteal lesions using percutaneous transluminal balloon angioplasty or first-generation of peripheral stents has been associated with unacceptable one-year restenosis rates. However, with recent advances in equipment and techniques, a better primary patency rate is expected. This study was conducted to detect the long-term primary patency rate of nitinol self-expandable stents implanted in long, totally occluded femoropopliteal lesions TransAtlantic Inter-Society Census (TASC II type C & D), and determine the predictors of reocclusion or restenosis in the stented segments. The demographics, clinical, anatomical, and procedural data of 213 patients with 240 de novo totally occluded femoropopliteal (TASC II type C & D) lesions treated with nitinol self-expandable stents were retrospectively analysed. Of these limbs, 159 (66.2%) presented with intermittent claudication, while 81 (33.8%) presented with critical limb ischaemia. The mean-time of follow-up was 36±22.6 months, (range: 6.3-106.2 months). Outcomes evaluated were, primary patency rate and predictors of reocclusion or restenosis in the stented segments. The mean age of the patients was 70.9±9.3 years, with male gender 66.2%. Mean pre-procedural ABI was 0.45±0.53. One-hundred-and-seventy-five (73%) lesions were TASC II type C, while 65 (27%) were type D lesions. The mean length of the lesions was 17.9±11.3mm. Procedure related complications occurred in 10 (4.1%) limbs. There was no periprocedural mortality. Reocclusion and restenosis were detected during follow-up in 45 and 30 limbs respectively, and all were re-treated by endovascular approach. None of the patients required major amputation. Primary patency rates were 81.4±1.1%, 77.7±1.9% and 74.4±2.8% at 12, 24, and 36 months respectively. Male gender, severe calcification, and TASC II D lesion were independent predictors for reocclusion, while predictors of restenosis were DM, smoking and TASC II D lesions

  9. The use of self-expanding silicone stents in esophageal cancer care: optimal pre-, peri-, and postoperative care.

    PubMed

    Martin, Robert; Duvall, Ryan; Ellis, Susan; Scoggins, Charles R

    2009-03-01

    Preoperative nutritional supplementation, management of esophageal leaks, and postoperative anastomotic strictures still remain common problems in the management of esophageal cancer. Jejunal feeding tubes, total parenteral nutrition (TPN) with nasogastric suction, and repeated esophageal dilations remain the most common treatments, respectively. The aim of this study was to evaluate the use of removable silicone stents in (1) the preoperative nutritional optimization during neoadjuvant therapy, (2) the management of perioperative anastomotic leak, and (3) the management of postoperative anastomotic strictures. Review of our prospectively maintained esophageal database identified 15 patients who had removable self-expanding silicone stents placed in the management of one of these three management problems from July 2004 to August 2006. Preoperative therapy: Five patients underwent initial stent placement in preparation for neoadjuvant therapy. Dysphagia relief was seen in 100% of patients, with optimal caloric needs taken within 24 h of placement. All patients tolerated neoadjuvant therapy without delay from dehydration or malnutrition. One stent migration was found at the time of operation, which was removed without sequelae. Perioperative therapy: Five patients developed delayed (>10 days) esophageal leaks that were managed with removable esophageal stent and percutaneous drainage (in three patients). All patients had successful exclusion of the leak on the day of the procedure with resumption of oral intake on the evening of procedure. All five healed leaks without sequelae. Postoperative therapy: Five patients developed postoperative anastomotic strictures that required dilation and placement of removable esophageal stent. The median number of dilations was 1 (range 1-2), with all stents placed for approximate 3 months duration. All patients had immediate dysphagia relief after stent placement. Removable esophageal stents are novel treatment option to optimize

  10. Rare Esophageal Migration of AXIOS Stent Used for Walled-off Pancreatic Necrosis Drainage

    PubMed Central

    Renno, Anas; Hammad, Tariq; Nawras, Ali

    2017-01-01

    The AXIOS stent (Boston Scientific, Marlborough, MA) is a novel lumen-apposing self-expandable metallic stent designed for enteric drainage of nonadherent lumens. Efficacy and safety of using the AXIOS stent for pancreatic fluid drainage have been consistently shown in several studies. Although it is less common with this novel stent, stent migration still may happen. We present a case of AXIOS stent migration into the esophagus. PMID:28584846

  11. Stenting of the Upper Gastrointestinal Tract: Current Status

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Katsanos, Konstantinos; Sabharwal, Tarun, E-mail: tarun.sabharwal@gstt.nhs.uk; Adam, Andreas

    2010-08-15

    Minimally invasive image-guided insertion of self-expanding metal stents in the upper gastrointestinal tract is the current treatment of choice for palliation of malignant esophageal or gastroduodenal outlet obstructions. A concise review is presented of contemporary stenting practice of the upper gastrointestinal tract, and the procedures in terms of appropriate patient evaluation, indications, and contraindications for treatment are analyzed, along with available stent designs, procedural steps, clinical outcomes, inadvertent complications, and future technology. Latest developments include biodegradable polymeric stents for benign disease and radioactive or drug-eluting stents for malignant obstructions.

  12. In-situ investigation of stress conditions during expansion of bare metal stents and PLLA-coated stents using the XRD sin(2)ψ-technique.

    PubMed

    Kowalski, Wolfgang; Dammer, Markus; Bakczewitz, Frank; Schmitz, Klaus-Peter; Grabow, Niels; Kessler, Olaf

    2015-09-01

    Drug eluting stents (DES) consist of platform, coating and drug. The platform often is a balloon-expandable bare metal stent made of the CoCr alloy L-605 or stainless steel 316 L. The function of the coating, typically a permanent polymer, is to hold and release the drug, which should improve therapeutic outcome. Before implantation, DES are compressed (crimped) to allow implantation in the human body. During implantation, DES are expanded by balloon inflation. Crimping, as well as expansion, causes high stresses and high strains locally in the DES struts, as well as in the polymer coating. These stresses and strains are important design criteria of DES. Usually, they are calculated numerically by finite element analysis (FEA), but experimental results for validation are hardly available. In this work, the X-ray diffraction (XRD) sin(2)ψ-technique is applied to in-situ determination of stress conditions of bare metal L-605 stents, and Poly-(L-lactide) (PLLA) coated stents. This provides a realistic characterization of the near-surface stress state and a validation option of the numerical FEA. XRD-results from terminal stent struts of the bare metal stent show an increasing compressive load stress in tangential direction with increasing stent expansion. These findings correlate with numerical FEA results. The PLLA-coating also bears increasing compressive load stress during expansion. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Customized Hinged Covered Metallic Stents for the Treatment of Benign Main Bronchial Stenosis.

    PubMed

    Han, Xinwei; Al-Tariq, Quazi; Zhao, Yanle; Li, Lei; Cheng, Zhe; Wang, Huaqi; Liu, Chao; Jiao, Dechao; Wu, Gang

    2017-08-01

    To address the limitations of silicone stents, we designed a hinged self-expandable covered metallic stent. The aim of this study was to evaluate the safety and efficacy of the customized stents in clinical applications. This was a retrospective analysis. Under conscious sedation and local anesthesia, the stents were implanted or removed by interventional radiologists, with fluoroscopic guidance. Of 24 patients with benign main bronchial stenosis, stents were successfully placed in 21 (87.5%). The low-pressure balloon before dilation failed in 1 case (4.17%) of left main bronchial cicatricial stenosis. In 2 other cases (8.33%), stent placement was abandoned. Stents were successfully removed between 29 and 103 days after the procedure. After stent removal, the follow-up lasted for at least 12 months. Restenosis occurred only in 1 case (4.55%) owing to bronchial collapse 3 days after stent removal. Dyspnea occurred in another case (4.55%) at 2 months after retrieval; recurrence was confirmed using bronchoscopy, leading to a left pneumonectomy. The described procedure is safe and easy to be performed and avoids the use of intubation, bronchoscopy, and general anesthesia. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  14. [An Analysis of Placement of a Self-Expanding Metallic Stent as Bridge to Surgery for Surgical Resection of StageⅣ Obstructive Colorectal Cancers].

    PubMed

    Kawahara, Yohei; Terada, Itsuro; Terai, Shiro; Watanabe, Toshifumi; Amaya, Koji; Yamamoto, Seiichi; Kaji, Masahide; Maeda, Kiichi; Shimizu, Koichi

    2015-11-01

    In our institution, placement of a self-expanding metallic stent (SEMS) for obstructive colorectal cancer to avoid emergency operations, namely as a bridge to surgery (BTS), was introduced in April 2012. Here, we assess the efficacy and safety of pre-operative SEMS placement for treatment of Stage Ⅳ obstructive colorectal cancer. We analyzed a total of 44 cases of Stage Ⅳ colorectal cancer, which consisted of 13 obstructive cases that were surgically resected following SEMS placement as BTS (BTS group), and 31 cases that were resected in elective operations without pre-operative SEMS placement (Ope group), from April 2012 to August 2014. None of the patients had any adverse events during the SEMS procedure or after SEMS placement, and all patients of BTS group could undergo the planned operations after sufficient decompression. In the postoperative period, 1 patient of BTS group (7.7%) had anastomosis bleeding, but no other complications, including anastomosis leakage, were observed in BTS group. However more progressive primary tumors were resected in BTS group (p=0.0115), there were no significant differences for post-operative course between the 2 groups; this indicated avoiding high-risk emergency operations contributed to adequate short-term outcomes in BTS group comparable to those in Ope group. SEMS placement as BTS could be performed safely for Stage Ⅳ obstructive colorectal cancer cases, and was 1 of the effective strategies for local treatment.

  15. Percutaneous Transhepatic Biliary Stenting with Uncovered Self-Expandable Metallic Stents in Patients with Malignant Biliary Obstruction – Efficacy and Survival Analysis

    PubMed Central

    Pranculis, Andrius; Kievišienė, Lina; Vaičius, Artūras; Vanagas, Tomas; Kaupas, Rytis Stasys; Dambrauskas, Žilvinas

    2017-01-01

    Summary Background The aim of this study was to assess short- and long-term outcomes of malignant biliary obstruction (MBO) treatment by percutaneous transhepatic biliary stenting (PTBS) with uncovered selfexpandable metallic stents (SEMS), and to identify predictors of survival. Material/Methods A nine-year, single-centre study from a prospectively collected database included 222 patients with inoperable MBO treated by PTBS with uncovered nitinol SEMS. Results Technical and clinical success rates were 95.9% and 82.4%, respectively. The total rate of postprocedural complications was 14.4%. The mean durations of the primary and secondary stent patency were 114.7±15.1 and 146.4±21.2 days, respectively. The 30-day mortality rate was 15.3% with no procedure-related deaths. The mean estimated length of survival was 143.3±20.6 days. Independent predictors increasing the risk of death included higher than 115 μmol/L serum bilirubin 2–5 days after biliary stenting (HR 3.274, P=0.019), distal (non-hilar) obstruction of the bile ducts (HR 3.711, P=0.008), Bismuth-Corlette type IV stricture (HR 2.082, P=0.008), obstruction due to gallbladder cancer (HR 31.029, P=0.012) and only partial drainage of liver parenchyma (HR 4.158, P=0.040). Conclusions PTBS with uncovered SEMS is an effective and safe method for palliative treatment of MBO. Serum bilirubin higher than 115 μmol/L 2–5 days after the procedure has a significant negative impact on patients’ survival. Lower survival is also determined by distal bile duct obstruction, Bismuth– Corlette type IV stricture, biliary obstruction caused by gallbladder cancer and when only partial liver drainage is applied. PMID:29662569

  16. Nine-Month Outcomes of the DURABILITY Iliac Study on Self-Expanding Stents for Symptomatic Peripheral Artery Disease.

    PubMed

    Faries, Peter; Jaff, Michael; Peeters, Patrick; Khatib, Yazan; Roberts, David; Bosiers, Marc; Malik, Rajesh; Ravin, Reid; Rundback, John

    2018-04-17

    The DURABILITY Iliac clinical study evaluated the safety and effectiveness of two nitinol self-expanding stents for the treatment of atherosclerotic common and external iliac artery lesions up to 10 cm in length and >50% stenosis in subjects with Rutherford Classification peripheral arterial disease stages 2-4. DURABILITY Iliac was a prospective, multicenter, core lab adjudicated, nonrandomized clinical study enrolling 75 subjects from 15 sites in the United States and Europe. Clinical follow-up visits were at 30 days, 9 months, and 1, 2, and 3 years post procedure. The primary outcome measured was the major adverse event rate (MAE) at 9 months, defined as a composite of periprocedural death, in-hospital myocardial infarction (MI), clinically-driven target lesion revascularization (CD-TLR), and amputation of the treated limb through 9 months post-procedure. Secondary outcomes included primary patency rate at 9 months, clinically-driven target vessel revascularization (CD-TVR), change in ankle-brachial index, and change in Walking Impairment Questionnaire score at 30 days and 9 months. Device success was defined as the ability to deploy the stent as intended at the treatment site. The MAE rate at 9 months was 1.3% (1/75), with 1 subject experiencing a CD-TLR. No periprocedural deaths, myocardial infarctions, or amputations were reported. Primacy patency at 9 months was 95.8%. Freedom from CD-TVR was 98.6% at 9 months. Subjects improved in Walking Impairment Questionnaire scores for all categories (walking impairment, walking speed, walking distance, and stair climbing) at the 30-day and 9-month visit. Device success was 100%. The 9-month results of the DURABILITY Iliac study demonstrate the safety and effectiveness of 2 nitinol self-expanding stents for the treatment of atherosclerotic lesions of the common and external iliac arteries. Copyright © 2018. Published by Elsevier Inc.

  17. Partially covered metal stents have longer patency than uncovered and fully covered metal stents in the management of distal malignant biliary obstruction: a retrospective study.

    PubMed

    Yokota, Yudai; Fukasawa, Mitsuharu; Takano, Shinichi; Kadokura, Makoto; Shindo, Hiroko; Takahashi, Ei; Hirose, Sumio; Kawakami, Satoshi; Fukasawa, Yoshimitsu; Sato, Tadashi; Enomoto, Nobuyuki

    2017-10-11

    Self-expandable metal stents (SEMSs) are widely used for malignant biliary obstructions. Nitinol-covered SEMSs have been developed to improve stent patency. Currently, SEMSs may be uncovered, partially covered, or fully covered; however, there is no consensus on the best stent type for the management of malignant distal biliary obstruction (MDBO). Patients with unresectable MDBO receiving SEMS (Wallflex™) were retrospectively analyzed. Time to recurrent biliary obstruction (TRBO) and survival time were compared among the three types of SEMSs. Univariate and multivariate analyses were performed to identify risk factors for stent dysfunction. In total, 101 patients received SEMSs for unresectable MDBO (44 uncovered, 28 partially covered, and 29 fully covered SEMSs). Median survival time was 200, 168, and 276 days in the uncovered, partially covered, and fully covered SEMSs groups, respectively. There were no differences in survival among the three groups. Median TRBO was 199, 444, and 194 days in the uncovered, partially covered, and fully covered SEMSs groups, respectively. Partially covered SEMSs had longer TRBO than uncovered (p = 0.013) and fully covered (p = 0.010) SEMSs. Tumor ingrowth occurred only with uncovered SEMSs and stent migration occurred only with fully covered SEMSs. Multivariate analyses confirmed that partially covered SEMSs have lower risk of dysfunction. Partially covered SEMSs with a proximal uncovered flared end have longer patency than uncovered and fully covered SEMSs by preventing tumor ingrowth and stent migration.

  18. Double stenting with silicone and metallic stents for malignant airway stenosis.

    PubMed

    Matsumoto, Keitaro; Yamasaki, Naoya; Tsuchiya, Tomoshi; Miyazaki, Takuro; Kamohara, Ryotaro; Hatachi, Go; Nagayasu, Takeshi

    2017-08-01

    For severe malignant airway stenosis, there are several types of commercially available airway stents, and each has its own advantages and disadvantages. We herein describe the safety and efficacy of combination stenting with silicone and metallic stents for patients with extended malignant airway stenosis. Seven patients with malignant airway stenosis were treated via combination stenting with a silicone stent and a metallic stent for extended airway stenosis from the central to peripheral airways. Five patients were diagnosed with advanced esophageal cancer, two of whom had tracheoesophageal fistulas. One patient had adenoid cystic carcinoma, and another had mediastinal tumor. There were no specific complications related to the double stenting. Combination stenting with silicone and metallic stents proved to be a safe option for patients with severe, extended, and complicated malignant airway stenosis.

  19. Effect of Covered Metallic Stents Compared With Plastic Stents on Benign Biliary Stricture Resolution: A Randomized Clinical Trial.

    PubMed

    Coté, Gregory A; Slivka, Adam; Tarnasky, Paul; Mullady, Daniel K; Elmunzer, B Joseph; Elta, Grace; Fogel, Evan; Lehman, Glen; McHenry, Lee; Romagnuolo, Joseph; Menon, Shyam; Siddiqui, Uzma D; Watkins, James; Lynch, Sheryl; Denski, Cheryl; Xu, Huiping; Sherman, Stuart

    Endoscopic placement of multiple plastic stents in parallel is the first-line treatment for most benign biliary strictures; it is possible that fully covered, self-expandable metallic stents (cSEMS) may require fewer endoscopic retrograde cholangiopancreatography procedures (ERCPs) to achieve resolution. To assess whether use of cSEMS is noninferior to plastic stents with respect to stricture resolution. Multicenter (8 endoscopic referral centers), open-label, parallel, randomized clinical trial involving patients with treatment-naive, benign biliary strictures (N = 112) due to orthotopic liver transplant (n = 73), chronic pancreatitis (n = 35), or postoperative injury (n = 4), who were enrolled between April 2011 and September 2014 (with follow-up ending October 2015). Patients with a bile duct diameter less than 6 mm and those with an intact gallbladder in whom the cystic duct would be overlapped by a cSEMS were excluded. Patients (N = 112) were randomized to receive multiple plastic stents or a single cSEMS, stratified by stricture etiology and with endoscopic reassessment for resolution every 3 months (plastic stents) or every 6 months (cSEMS). Patients were followed up for 12 months after stricture resolution to assess for recurrence. Primary outcome was stricture resolution after no more than 12 months of endoscopic therapy. The sample size was estimated based on the noninferiority of cSEMS to plastic stents, with a noninferiority margin of -15%. There were 55 patients in the plastic stent group (mean [SD] age, 57 [11] years; 17 women [31%]) and 57 patients in the cSEMS group (mean [SD] age, 55 [10] years; 19 women [33%]). Compared with plastic stents (41/48, 85.4%), the cSEMS resolution rate was 50 of 54 patients (92.6%), with a rate difference of 7.2% (1-sided 95% CI, -3.0% to ∞; P < .001). Given the prespecified noninferiority margin of -15%, the null hypothesis that cSEMS is less effective than plastic stents was rejected. The

  20. Endoscopic management of unresectable malignant gastroduodenal obstruction with a nitinol uncovered metal stent: A prospective Japanese multicenter study

    PubMed Central

    Sasaki, Reina; Sakai, Yuji; Tsuyuguchi, Toshio; Nishikawa, Takao; Fujimoto, Tatsuya; Mikami, Shigeru; Sugiyama, Harutoshi; Yokosuka, Osamu

    2016-01-01

    AIM: To determine the safety and efficacy of endoscopic duodenal stent placement in patients with malignant gastric outlet obstruction. METHODS: This prospective, observational, multicenter study included 39 consecutive patients with malignant gastric outlet obstruction. All patients underwent endoscopic placement of a nitinol, uncovered, self-expandable metal stent. The primary outcome was clinical success at 2 wk after stent placement that was defined as improvement in the Gastric Outlet Obstruction Scoring System score relative to the baseline. RESULTS: Technical success was achieved in all duodenal stent procedures. Procedure-related complications occurred in 4 patients (10.3%) in the form of mild pneumonitis. No other morbidities or mortalities were observed. The clinical success rate was 92.3%. The mean survival period after stent placement was 103 d. The mean period of stent patency was 149 d and the patency remained acceptable for the survival period. Stent dysfunction occurred in 3 patients (7.7%) on account of tumor growth. CONCLUSION: Endoscopic management using duodenal stents for patients with incurable malignant gastric outlet obstruction is safe and improved patients’ quality of life. PMID:27076769

  1. Use of a specially designed partially covered self-expandable metal stent (PSEMS) with a 40-mm diameter for the treatment of upper gastrointestinal suture or staple line leaks in 11 cases.

    PubMed

    Fischer, Andreas; Bausch, Dirk; Richter-Schrag, Hans-Juergen

    2013-02-01

    The use of self-expandable stents to treat postoperative leaks and fistula in the upper gastrointestinal (GI) tract is an established treatment for leaks of the upper GI tract. However, lumen-to-stent size discrepancies (i.e., after sleeve gastrectomy or esophageal resection) may lead to insufficient sealing of the leaks requiring further surgical intervention. This is mainly due to the relatively small diameter (≤30 mm) of commonly used commercial stents. To overcome this problem, we developed a novel partially covered stent with a shaft diameter of 36 mm and a flare diameter of 40 mm. From September 2008 to September 2010, 11 consecutive patients with postoperative leaks were treated with the novel large diameter stent (gastrectomy, n = 5; sleeve gastrectomy, n = 2; fundoplication after esophageal perforation, n = 2; Roux-en-Y gastric bypass, n = 1; esophageal resection, n = 1). Treatment with commercially available stents (shaft/flare: 23/28 mm and 24/30 mm) had been unsuccessful in three patients before treatment with the large diameter stent. Due to dislocation, the large diameter stent was anchored in four patients (2× intraoperatively with transmural sutures, 2× endoscopically with transnasally externalized threads). Treatment was successful in 11 of 11 patients. Stent placement and removal was easy and safe. The median residence time of the stent was 24 (range, 18-41) days. Stent dislocation occurred in four cases (36 %). It was treated by anchoring the stent. Mean follow-up was 25 (range, 14-40) months. No severe complication occurred during or after intervention and no patient was dysphagic. Using the novel large diameter, partially covered stent to seal leaks in the upper GI tract is safe and effective. The large diameter of the stent does not seem to injure the wall of the upper GI tract. However, stent dislocation sometimes requires anchoring of the stent with sutures or transnasally externalized threads.

  2. Outcome and risk factors assessment for adverse events in advanced esophageal cancer patients after self-expanding metal stents placement.

    PubMed

    Rodrigues-Pinto, E; Pereira, P; Coelho, R; Andrade, P; Ribeiro, A; Lopes, S; Moutinho-Ribeiro, P; Macedo, G

    2017-02-01

    Self-expanding metal stents (SEMS) are the treatment of choice for advanced esophageal cancers. Literature is scarce on risk factors predictors for adverse events after SEMS placement. Assess risk factors for adverse events after SEMS placement in advanced esophageal cancer and evaluate survival after SEMS placement. Cross-sectional study of patients with advanced esophageal cancer referred for SEMS placement, during a period of 3 years. Ninety-seven patients with advanced esophageal cancer placed SEMS. Adverse events were more common when tumors were located at the level of the distal esophagus/cardia (47% vs 23%, P = 0.011, OR 3.1), with statistical significance being kept in the multivariate analysis (OR 3.1, P = 0.018). Time until adverse events was lower in the tumors located at the level of the distal esophagus/cardia (P = 0.036). Survival was higher in patients who placed SEMS with curative intent (327 days [126-528] vs. 119 days [91-147], P = 0.002) and in patients submitted subsequently to surgery compared with those who did just chemo/radiotherapy or who did not do further treatment (563 days [378-748] vs. 154 days [133-175] vs. 46 days [20-72], P < 0.001). Subsequent treatment kept statistical significance in the multivariate analysis (HR 3.4, P < 0.001). SEMS allow palliation of dysphagia in advanced esophageal cancer and are associated with an increased out-of-hospital survival, as long as there are conditions for further treatments. Tumors located at the level of the distal esophagus/cardia are associated with a greater number of adverse events, which also occur earlier. © 2016 International Society for Diseases of the Esophagus.

  3. Upper Gastrointestinal Stent Insertion in Malignant and Benign Disorders

    PubMed Central

    Kang, Hyoun Woo

    2015-01-01

    Upper gastrointestinal (GI) stents are increasingly being used to manage upper GI obstructions. Initially developed for palliative treatment of esophageal cancer, upper GI stents now play an emerging role in benign strictures of the upper GI tract. Because recurrent obstruction and stent-related complications are common, new modifications of stents have been implemented. Self-expandable metal stents (SEMS) have replaced older plastic stents. In addition, newly designed SEMS have been developed to prevent complications. This review provides an overview of the various types, indications, methods, complications, and clinical outcomes of upper GI stents in a number of malignant and benign disorders dividing the esophagus and gastroduodenum. PMID:26064817

  4. Palliative treatment with radiation-emitting metallic stents in unresectable Bismuth type III or IV hilar cholangiocarcinoma.

    PubMed

    Lu, Jian; Guo, Jin-He; Zhu, Hai-Dong; Zhu, Guang-Yu; Wang, Yong; Zhang, Qi; Chen, Li; Wang, Chao; Pan, Tian-Fan; Teng, Gao-Jun

    2017-01-01

    The emerging data for stenting in combination with brachytherapy in unresectable hilar cholangiocarcinoma are encouraging. The aim of this study was to evaluate the efficacy and safety of radiation-emitting metallic stents (REMS) for unresectable Bismuth type III or IV hilar cholangiocarcinoma. Consecutive patients who underwent percutaneous placement with REMS or uncovered self-expandable metallic stent (SEMS) for unresectable Bismuth type III or IV hilar cholangiocarcinoma between September 2011 and April 2016 were identified into this retrospective study. Data on patient demographics and overall survival, functional success, stent patency and complications were collected at the authors' hospital. A total of 59 patients were included: 33 (55.9%) in the REMS group and 26 (44.1%) in the SEMS group. The median overall survival was 338 days in the REMS group and 141 days in the SEMS group (p<0.001). The median stent patency time was 385 days for REMS and 142 days for SEMS (p<0.001). The functional success rate (87.9% vs 84.6%, p=0.722) and incidence of overall complications (27.3% vs 26.9%, p=0.999) did not differ in the two groups. Placement with REMS is safe and effective in palliation for unresectable Bismuth type III or IV hilar cholangiocarcinoma, and seems to prolong survival as well as patency of stent in these patients.

  5. Fabrication of a silver particle-integrated silicone polymer-covered metal stent against sludge and biofilm formation and stent-induced tissue inflammation

    PubMed Central

    Lee, Tae Hoon; Jang, Bong Seok; Jung, Min Kyo; Pack, Chan Gi; Choi, Jun-Ho; Park, Do Hyun

    2016-01-01

    To reduce tissue or tumor ingrowth, covered self-expandable metal stents (SEMSs) have been developed. The effectiveness of covered SEMSs may be attenuated by sludge or stone formation or by stent clogging due to the formation of biofilm on the covering membrane. In this study, we tested the hypothesis that a silicone membrane containing silver particles (Ag-P) would prevent sludge and biofilm formation on the covered SEMS. In vitro, the Ag-P-integrated silicone polymer-covered membrane exhibited sustained antibacterial activity, and there was no definite release of silver ions from the Ag-P-integrated silicone polymer membrane at any time point. Using a porcine stent model, in vivo analysis demonstrated that the Ag-P-integrated silicone polymer-covered SEMS reduced the thickness of the biofilm and the quantity of sludge formed, compared with a conventional silicone-covered SEMS. In vivo, the release of silver ions from an Ag-P-integrated silicone polymer-covered SEMS was not detected in porcine serum. The Ag-P-integrated silicone polymer-covered SEMS also resulted in significantly less stent-related bile duct and subepithelium tissue inflammation than a conventional silicone polymer-covered SEMS. Therefore, the Ag-P-integrated silicone polymer-covered SEMS reduced sludge and biofilm formation and stent-induced pathological changes in tissue. This novel SEMS may prolong the stent patency in clinical application. PMID:27739486

  6. Fabrication of a silver particle-integrated silicone polymer-covered metal stent against sludge and biofilm formation and stent-induced tissue inflammation.

    PubMed

    Lee, Tae Hoon; Jang, Bong Seok; Jung, Min Kyo; Pack, Chan Gi; Choi, Jun-Ho; Park, Do Hyun

    2016-10-14

    To reduce tissue or tumor ingrowth, covered self-expandable metal stents (SEMSs) have been developed. The effectiveness of covered SEMSs may be attenuated by sludge or stone formation or by stent clogging due to the formation of biofilm on the covering membrane. In this study, we tested the hypothesis that a silicone membrane containing silver particles (Ag-P) would prevent sludge and biofilm formation on the covered SEMS. In vitro, the Ag-P-integrated silicone polymer-covered membrane exhibited sustained antibacterial activity, and there was no definite release of silver ions from the Ag-P-integrated silicone polymer membrane at any time point. Using a porcine stent model, in vivo analysis demonstrated that the Ag-P-integrated silicone polymer-covered SEMS reduced the thickness of the biofilm and the quantity of sludge formed, compared with a conventional silicone-covered SEMS. In vivo, the release of silver ions from an Ag-P-integrated silicone polymer-covered SEMS was not detected in porcine serum. The Ag-P-integrated silicone polymer-covered SEMS also resulted in significantly less stent-related bile duct and subepithelium tissue inflammation than a conventional silicone polymer-covered SEMS. Therefore, the Ag-P-integrated silicone polymer-covered SEMS reduced sludge and biofilm formation and stent-induced pathological changes in tissue. This novel SEMS may prolong the stent patency in clinical application.

  7. Conformability of balloon-expandable stents to the carotid siphon: an in vitro study.

    PubMed

    du Mesnil de Rochemont, R; Yan, B; Zanella, F E; Rüfenacht, D A; Berkefeld, J

    2006-02-01

    Endovascular placement of coronary balloon-expandable stents in patients with recurrent cerebral ischemia has emerged as a treatment option for intracranial arterial occlusive disease. We have developed an in vitro model matching the tortuous curve of the carotid siphon that allows the assessment of apposition of stents to a curved vessel wall. Six types of balloon-expandable coronary stents were implanted in a silicone model of the carotid siphon. Digital radiographs and 3D rotational angiograms were obtained. Stent morphology was evaluated and the degree of apposition between stent and wall of the model was measured on a digital workstation. All 6 stents showed lack of apposition between stent and the wall at the convexity of the anterior segment of the carotid siphon and the wall at the concavity at both extremities of the stent. In and around the curve, the modules of the stents did not expand completely to their nominal diameter and were distorted to an oval shape. The tested coronary balloon-expandable stents did not completely conform to the vessel wall of the model of the carotid siphon and further development is needed to approach the goal of an "ideal intracranial stent."

  8. Endoscopic bilateral stent-in-stent placement for malignant hilar obstruction using a large cell type stent.

    PubMed

    Park, Jin Myung; Lee, Sang Hyub; Chung, Kwang Hyun; Jang, Dong Kee; Ryu, Ji Kon; Kim, Yong-Tae; Lee, Jae Min; Paik, Woo Hyun

    2016-12-01

    Bilateral stent-in-stent (SIS) self-expandable metal stent placement is technically challenging for palliation of unresectable malignant hilar obstruction. In the SIS technique, the uniform large cell type biliary stent facilitates contralateral stent deployment through the mesh of the first metallic stent. This study aimed to assess the technical success and clinical effectiveness of this technique with a uniform large cell type biliary stent. Thirty-one patients who underwent bilateral SIS placement using a large cell type stent were reviewed retrospectively. All patients showed malignant hilar obstruction (Bismuth types II, III, IV) with different etiologies. Sixteen (51.6%) patients were male. The mean age of the patients was 67.0+/-14.0 years. Most patients were diagnosed as having hilar cholangiocarcinoma (58.1%) and gallbladder cancer (29.0%). Technical success rate was 83.9%. Success was achieved more frequently in patients without masses obstructing the biliary confluence (MOC) than those with MOC (95.2% vs 60.0%, P=0.03). Functional success rate was 77.4%. Complications occurred in 29.0% of the patients. These tended to occur more frequently in patients with MOC (50.0% vs 19.0%, P=0.11). Median time to recurrent biliary obstruction was 188 days and median survival was 175 days. The large cell type stent can be used efficiently for bilateral SIS placement in malignant hilar obstruction. However, the risk of technical failure increases in patients with MOC, and caution is needed to prevent complications for these patients.

  9. Comparison of covered versus uncovered wire mesh stents in the canine biliary tract.

    PubMed

    Silvis, S E; Sievert, C E; Vennes, J A; Abeyta, B K; Brennecke, L H

    1994-01-01

    Self-expanding wire mesh stents have been developed for endoscopic placement across malignant biliary strictures, but tumor ingrowth may limit the usefulness of open mesh stents. We reasoned that coating the wire mesh might prevent tumor ingrowth. Tissue response to covered and uncovered stents was compared in dogs. Stents were surgically placed in the bile ducts of 22 mongrel dogs through the sphincter of Oddi. Either a silicone-covered stent or an uncovered stent was inserted. Liver function test values remained normal throughout a 1- or 3-month study. Necropsy revealed that all ducts were unobstructed. Bile duct histologic examination revealed mild-to-moderate cellular infiltration in all animals. Mucosal hyperplasia was more marked in the animals with uncovered stents and the bare wires became deeply embedded in bile duct epithelium, whereas the wires of covered stents did not. We conclude that covered stents are well tolerated by the canine bile duct. These results suggest that such stents may be removable, making self-expanding metal stents an appropriate treatment for both benign and malignant biliary strictures.

  10. Palliative Airway Stenting Performed Under Radiological Guidance and Local Anesthesia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Profili, Stefano; Manca, Antonio; Feo, Claudio F.

    2007-02-15

    Purpose. To assess the effectiveness of airway stenting performed exclusively under radiological guidance for the palliation of malignant tracheobronchial strictures. Methods. We report our experience in 16 patients with malignant tracheobronchial stricture treated by insertion of 20 Ultraflex self-expandable metal stents performed under fluoroscopic guidance only. Three patients presented dysphagia grade IV due to esophageal malignant infiltration; they therefore underwent combined airway and esophageal stenting. All the procedures were performed under conscious sedation in the radiological room; average procedure time was around 10 min, but the airway impediment never lasted more than 40 sec. Results. We obtained an overall technicalmore » success in 16 cases (100%) and clinical success in 14 patients (88%). All prostheses were successfully placed without procedural complications. Rapid clinical improvement with symptom relief and normalization of respiratory function was obtained in 14 cases. Two patients died within 48 hr from causes unrelated to stent placement. Two cases (13%) of migration were observed; they were successfully treated with another stent. Tumor overgrowth developed in other 2 patients (13%); however, no further treatment was possible because of extensive laryngeal infiltration. Conclusions. Tracheobronchial recanalization with self-expandable metal stents is a safe and effective palliative treatment for malignant strictures. Airway stenting performed exclusively under fluoroscopic view was rapid and well tolerated.« less

  11. Percutaneous treatment of adult isthmic aortic coarctation: acute and long-term clinical and imaging outcome with a self-expandable uncovered nitinol stent.

    PubMed

    Kische, Stephan; D'Ancona, Giuseppe; Stoeckicht, Yannik; Ortak, Jasmin; Elsässer, Albrecht; Ince, Hüseyin

    2015-01-01

    To present perioperative and long-term results of percutaneous treatment of adult isthmic coarctation of the aorta by means of a self-expandable closed-web uncovered nitinol stent (Sinus-XL, Optimed, Esslingen, Germany). Preoperative, perioperative, and long-term clinical and computed tomographic angiography data were collected and analyzed prospectively. A total of 52 consecutive patients were treated with the Sinus-XL stent. Mean age was 36.6 (21-67) years, peak invasive trans-coarctation of the aorta gradient was 54.7 ± 9.9 mm Hg, and upper body hypertension unresponsive to medical treatment was present in all patients. Mean stent diameter and length were 24.2 mm (22-28 mm) and 70.4 mm (40-80 mm), respectively. Eight patients (15.4%) required coarctation of the aorta predilatation. All patients underwent poststent dilatation with a noncompliant balloon. Postoperative peak gradient (3.3 ± 2.5 mm Hg) was reduced significantly (P < 0.001) and minimal aortic diameter was increased significantly (4.6 ± 1.9 versus 18.6 ± 2.5 mm; P < 0.001). All patients were discharged home (mean hospitalization, 3.5 days). At follow-up (47.6 months; 12-84), 1 (1.9%) noncardiovascular mortality was reported. Aortic computed tomography confirmed the absence of stent collapse and secondary migration and documented stability in aortic diameter (18.3 ± 2.7 mm). Thirty patients (57.7%) were completely weaned-off antihypertensive medications and their use dropped from 2.6 to 0.9 drugs/patient (P < 0.001). Ankle-brachial pressure index increased from 0.75 to 0.98 (P < 0.001). Adult coarctation of the aorta treatment by means of a self-expandable uncovered stent is safe and durable. The peculiar stent design maintains adequate localized radial strength over time with minimal trauma on the adjacent aortic wall and negligible device-related complications. Blood pressure control optimization is immediate and persistent even at long-term follow-up. © 2015 American Heart Association, Inc.

  12. [Complications and the management of fully covered retrievable metal stent placement in benign tracheal stenosis].

    PubMed

    Wang, Zheng-yu; Wang, Yong-li; Chen, Guang-li; Liang, Xi-hong; Wang, Zhen-chang; Ma, Jian-zhong; Wu, Guang-zhong; Zhang, Xiao-ping

    2012-11-01

    To study complications and the management of the use of covered retrievable expandable metallic stents in the treatment of benign tracheal stenosis. Fully covered retrievable metal stents were placed in 21 patients with benign tracheal stenosis. Stent-related complications and the management were reviewed and analysed. Twenty-eight fully covered retrievable metallic stents were successfully placed fluoroscopically in 21 patients. Stents were removed 4 - 12 months [mean (5.5 ± 2.2) mouths] after placement in all patients. Stent-related complications included granulation tissue (n = 18), stent migration (n = 4), stent expectoration (n = 2), halitosis (n = 8), mucous retention (n = 21) and mucus plugging (n = 1). Granulation tissue was removed with a carbon dioxide laser in 2 patients. Stents were replaced for 2 times and 3 times respectively in 2 patients after stent migration and stent expectoration. An additional stent was placed in 2 patients after stent migration. Symptom of halitosis was relieved after prolonged course of systemic antibiotics treatment in 8 patients. Symptom of mucous retention was relieved with nebulized saline and N-acetylcysteine saline inhalation. Mucous plug was expelled after severe coughing after suctioning using an aspirator in one patient. There were statistically significant differences in stricture diameter, rank of tachypnea and pulmonary function (FEV(1)) in all 21 patients before stent insertion and after stents removal. No patient has experienced recurrence during the follow-up period of 1 - 36 months [mean (23.2 ± 8.0) months]. Fully covered retrievable metallic stent may be a safe and effective in benign tracheal stenosis. Stent-related complications may be effectively managed.

  13. Evaluation of Quality of Life Following Placement of Self-Expanding Plastic Stents as a Bridge to Surgery in Patients Receiving Neoadjuvant Therapy for Esophageal Cancer

    PubMed Central

    Cannon, Robert M.; Brown, Russell E.; Ellis, Susan F.; Williams, Sharon; Scoggins, C.R.; Abbas, Abbas E.

    2014-01-01

    Purpose. To determine whether self-expanding plastic stent (SEPS) placement significantly improves quality of life and maintains optimal nutrition while allowing full-dose neoadjuvant therapy (NAT) in patients with esophageal cancer. Patients and Methods. A prospective, dual-institution, single-arm, phase II (http://ClinicalTrials.gov: NCT00727376) evaluation of esophageal cancer patients undergoing NAT prior to resection. All patients had a self-expanding polymer stent placed prior to NAT. The European Organisation for Research and Treatment of Cancer QLQ-C30 and QLQ-OG25, Functional Assessment of Cancer Therapy–Anorexia, and Functional Assessment of Cancer Therapy–General surveys were administered prior to stenting, within 1 week post-stent placement, and at the completion of neoadjuvant therapy. Results. Fifty-two patients were enrolled; 3 (5.8%) had stent migrations requiring replacement. There were no instances of esophageal erosion or perforation. All patients received some form of neoadjuvant therapy. Thirty-six (69%) received chemoradiation; 34 (93%) of these patients received the planned dose of chemotherapy, and 27 (75%) received the full planned dose of radiotherapy. There were 16 (31%) patients receiving chemotherapy alone; 12 (74%) of patients in the chemotherapy-alone group completed the planned dose of therapy. Conclusion. Placement of SEPS appears to provide significant improvement in quality of life related to dysphagia and eating restriction in patients with esophageal cancer undergoing neoadjuvant therapy. Consideration of SEPS instead of percutaneous feeding tube should be initiated as a first line in dysphagia palliation and NAT nutritional support. PMID:24567281

  14. Primary and revision efficacy of cross-wired metallic stents for endoscopic bilateral stent-in-stent placement in malignant hilar biliary strictures.

    PubMed

    Lee, T H; Moon, J H; Kim, J H; Park, D H; Lee, S S; Choi, H J; Cho, Y D; Park, S H; Kim, S J

    2013-01-01

    Endoscopic bilateral drainage for inoperable malignant hilar biliary strictures (HBS) using metal stents is considered to be technically difficult. Furthermore, endoscopic revision of bilateral stenting after occlusion can be challenging. This study was performed to evaluate the long-term efficacy of endoscopic bilateral stent-in-stent placement of cross-wired metallic stents in high-grade malignant HBS and planned endoscopic bilateral revision. A total of 84 patients with inoperable high-grade malignant HBS were enrolled from three academic tertiary referral centers. Two cross-wired metal stents were inserted using a bilateral stent-in-stent placement method. Bilateral endoscopic revision was also performed during follow-up using either identical metal stents or plastic stents. The main outcome measurements were technical and functional success, complications, stent patency, and endoscopic revision efficacy. The technical and clinical success rates of endoscopic bilateral stent-in-stent placement of cross-wired metallic stents were 95.2% (80/84) and 92.9% (78/84), respectively. Median patency (range) and survival were 238 days (10-429) and 256 days (10-1130), respectively. Obstruction of primary bilateral stents occurred in 30.8% (24/78) of patients with functionally successful stent placement. The technical and clinical success rates of planned bilateral endoscopic revision for occluded stents were 83.3% (20/24) and 79.2% (19/24), respectively. For revision, bilateral metallic stents were placed in 11 patients (55.0%); the remaining patients received plastic stents. Palliative endoscopic bilateral stent-in-stent placement of cross-wired metallic stents was effective in patients with inoperable HBS. Revision endoscopic bilateral stenting may be feasible and successful in cases where the primary deployed metal stents are occluded. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Management of embedded metallic stents used in the treatment of grades III and IV subglottic, and upper tracheal stenosis in adults.

    PubMed

    Sendi, Khalil; Al-Khatib, Talal; Ahmed, Duha G; Tonkul, Al-Baraa

    2014-11-01

    The aim of this study was to evaluate the post-operative complications of using balloon-expandable metallic stents in treatment of benign, major subglottic and tracheal stenosis in adult patients whom conventional therapy has failed and to demonstrate how to deal with these complications in the long run. A retrospective review of five cases; adlut patiets with benign, major subglottic and upper tracheal stenosis whom were treated with balloon expandable metallic stents at King Abdulaziz University Hospital, in the years between 2008 and 2013. Granulation tissue formed in five of the four cases and restenosis occurred. Other complications encountered were stent infection and dislodgment. The complications were managed by removing the stents surgically via a laryngofissure incision and required the placement of a Montgomery T-tube. Managing the restenosis due to granulation tissue formation around the metallic stents is best achieved by removing the embedded metallic stents surgically via open technique and then by placement of a Montgomery T-tube as a bridging option to successful decannulation. Open surgical procedures remain the mainstay treatment for advanced airway stenosis.

  16. Durability of the balloon-expandable covered versus bare-metal stents in the Covered versus Balloon Expandable Stent Trial (COBEST) for the treatment of aortoiliac occlusive disease.

    PubMed

    Mwipatayi, Bibombe P; Sharma, Surabhi; Daneshmand, Ali; Thomas, Shannon D; Vijayan, Vikram; Altaf, Nishath; Garbowski, Marek; Jackson, Mark

    2016-07-01

    The Covered vs Balloon Expandable Stent Trial (COBEST) is the first multicenter trial to investigate the patency of covered stents (CSs) and bare-metal stents (BMSs) in the treatment of aortoiliac arterial disease. The short-term results demonstrated that CSs were superior to BMSs in maintaining patency for TransAtlantic Inter-Society Consensus (TASC) C and D lesions at 18 months and were equivalent to BMSs for TASC B lesions. The current study was conducted to determine if the initial patency advantage of CSs over BMSs was sustained at the 5-year follow-up. A retrospective post hoc analysis of COBEST was performed. Originally, 125 patients with 168 iliac arteries were prospectively enrolled and randomly assigned to receive a CS or BMS. In this study, 77 of the 125 patients (61.6%; 119 limbs) were assessed at 60 months for the primary and secondary end points, with particular attention paid to the outcomes stratified according to TASC lesion severity. The primary end point was the rate of binary stenosis or freedom from stent occlusion of the treated area, as determined by ultrasound imaging or quantitative visual angiography. The 5-year results of the COBEST showed that the CS had a significantly higher patency rate than the BMS at 18, 24, 48, and 60 months (95.1%, 82.1%, 79.9%, 74.7% for CS vs 73.9%, 70.9%, 63% and 62.5% for BMS; log-rank test, P = .01). On multivariate analysis, the type of stent used (hazard ratio [HR], 2.797; 95% confidence interval [CI], 1.471-5.318; P = .002) and the Rutherford classification (HR, 2.019; 95% CI, 1.278-3.191; P = .026) significantly affected the adjusted primary patency. On subgroup analysis, the CS showed significantly higher patency and a survival benefit compared with the BMS in TASC C and D lesions (HR, 8.639; 95% CI, 54.253-75.753; P = .003). Moreover, fewer patients received target limb revascularization in the CS group than in the BMS group (odds ratio, 2.32; 95% CI, 1.47-3.36; P = .02); however, there was no

  17. Endoscopic management with inside stent for proximal benign biliary stricture after laparoscopic cholecystectomy.

    PubMed

    Sasahira, Naoki; Isayama, Hiroyuki; Kogure, Hirofumi; Tsujino, Takeshi; Koike, Kazuhiko

    2012-05-01

    Endoscopic placement of a plastic stent is the standard drainage for a symptomatic benign biliary stricture. Although a removable fully covered self-expandable metal stent has been applied for distal benign biliary stricture, placement of a plastic stent remains the standard treatment for proximal benign biliary stricture. Placement of a plastic stent above the papilla (inside stent) is an alternative to the conventional method because of its preventive effect against the dysfunction of the stent in patients with proximal benign biliary stricture. © 2012 The Authors. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

  18. Mechanical behavior of peripheral stents and stent-vessel interaction: A computational study

    NASA Astrophysics Data System (ADS)

    Dottori, Serena; Flamini, Vittoria; Vairo, Giuseppe

    2016-05-01

    In this paper stents employed to treat peripheral artery disease are analyzed through a three-dimensional finite-element approach, based on a large-strain and large-displacement formulation. Aiming to evaluate the influence of some stent design parameters on stent mechanics and on the biomechanical interaction between stent and arterial wall, quasi-static and dynamic numerical analyses are carried out by referring to computational models of commercially and noncommercially available versions of both braided self-expandable stents and balloon-expandable stents. Addressing isolated device models, opening mechanisms and flexibility of both opened and closed stent configurations are numerically experienced. Moreover, stent deployment into a stenotic peripheral artery and possible postdilatation angioplasty (the latter for the self-expandable device only) are simulated by considering different idealized vessel geometries and accounting for the presence of a stenotic plaque. Proposed results highlight important differences in the mechanical response of the two types of stents, as well as a significant influence of the vessel shape on the stress distributions arising upon the artery-plaque system. Finally, computational results are used to assess both the stent mechanical performance and the effectiveness of the stenting treatment, allowing also to identify possible critical conditions affecting the risk of stent fracture, tissue damage, and/or pathological tissue response.

  19. Very late stent thrombosis in a bare-metal stent, 9 years after implantation.

    PubMed

    Almasswary, Adel A

    2009-06-01

    Very late bare-metal stent thrombosis occurring beyond one year after stenting is uncommon. We report a case of bare-metal stent thrombosis presenting as acute myocardial infarction. The patient's stent was implanted 9 years ago, however, he was not adherent to his antiplatelet therapy (aspirin). This case highlights the importance of antiplatelet therapy in patients with stents even many years after implantation.

  20. Percutaneous unilateral biliary metallic stent placement in patients with malignant obstruction of the biliary hila and contralateral portal vein steno-occlusion.

    PubMed

    Son, Rak Chae; Gwon, Dong Il; Ko, Heung Kyu; Kim, Jong Woo; Ko, Gi-Young

    2015-01-01

    To investigate the outcomes of percutaneous unilateral metallic stent placement in patients with a malignant obstruction of the biliary hila and a contralateral portal vein steno-occlusion. Sixty patients with a malignant hilar obstruction and unilobar portal vein steno-occlusion caused by tumor invasion or preoperative portal vein embolization were enrolled in this retrospective study from October 2010 to October 2013. All patients were treated with percutaneous placement of a biliary metallic stent, including expanded polytetrafluoroethylene (ePTFE)-covered stents in 27 patients and uncovered stents in 33 patients. A total of 70 stents were successfully placed in 60 patients. Procedural-related minor complications, including self-limiting hemobilia (n = 2) and cholangitis (n = 4) occurred in six (10%) patients. Acute cholecystitis occurred in two patients. Successful internal drainage was achieved in 54 (90%) of the 60 patients. According to a Kaplan-Meier analysis, median survival time was 210 days (95% confidence interval [CI], 135-284 days), and median stent patency time was 133 days (95% CI, 94-171 days). No significant difference in stent patency was observed between covered and uncovered stents (p = 0.646). Stent dysfunction occurred in 16 (29.6%) of 54 patients after a mean of 159 days (range, 65-321 days). Unilateral placement of ePTFE-covered and uncovered stents in the hepatic lobe with a patent portal vein is a safe and effective method for palliative treatment of patients with a contralateral portal vein steno-occlusion caused by an advanced hilar malignancy or portal vein embolization. No significant difference in stent patency was detected between covered and uncovered metallic stents.

  1. Percutaneous Unilateral Biliary Metallic Stent Placement in Patients with Malignant Obstruction of the Biliary Hila and Contralateral Portal Vein Steno-Occlusion

    PubMed Central

    Son, Rak Chae; Ko, Heung Kyu; Kim, Jong Woo; Ko, Gi-Young

    2015-01-01

    Objective To investigate the outcomes of percutaneous unilateral metallic stent placement in patients with a malignant obstruction of the biliary hila and a contralateral portal vein steno-occlusion. Materials and Methods Sixty patients with a malignant hilar obstruction and unilobar portal vein steno-occlusion caused by tumor invasion or preoperative portal vein embolization were enrolled in this retrospective study from October 2010 to October 2013. All patients were treated with percutaneous placement of a biliary metallic stent, including expanded polytetrafluoroethylene (ePTFE)-covered stents in 27 patients and uncovered stents in 33 patients. Results A total of 70 stents were successfully placed in 60 patients. Procedural-related minor complications, including self-limiting hemobilia (n = 2) and cholangitis (n = 4) occurred in six (10%) patients. Acute cholecystitis occurred in two patients. Successful internal drainage was achieved in 54 (90%) of the 60 patients. According to a Kaplan-Meier analysis, median survival time was 210 days (95% confidence interval [CI], 135-284 days), and median stent patency time was 133 days (95% CI, 94-171 days). No significant difference in stent patency was observed between covered and uncovered stents (p = 0.646). Stent dysfunction occurred in 16 (29.6%) of 54 patients after a mean of 159 days (range, 65-321 days). Conclusion Unilateral placement of ePTFE-covered and uncovered stents in the hepatic lobe with a patent portal vein is a safe and effective method for palliative treatment of patients with a contralateral portal vein steno-occlusion caused by an advanced hilar malignancy or portal vein embolization. No significant difference in stent patency was detected between covered and uncovered metallic stents. PMID:25995688

  2. Balloon-Expandable Stent Graft for Treating Uretero-Iliac Artery Fistula

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guntau, Moritz, E-mail: guntau@med.uni-marburg.de; Hegele, Axel; Rheinheimer, Stephan

    PurposeTo evaluate the safety, efficacy and outcome of percutaneous balloon-expandable covered stent graft placement for uretero-iliac artery fistula (UAF) treatment.MethodsThis retrospective study evaluated the single-center experience of percutaneous balloon-expandable covered stent graft placement (ADVANTA™, Atrium Hudson, NH, USA) in UAF. Data were obtained from a prospective institutional database. Patient follow-up included complications, symptoms recurrence and mortality rate.ResultsTen UAFs in eight patients (3 males; 5 females) with a mean age of 64.5 (35–77) years were identified. All patients had a history pelvic malignancy, extirpative surgery (n = 6), long-term ureteral stenting (n = 7) and pelvic radiation (n = 5). All procedures were completed successfully without complications.more » Thirty-day mortality rate was zero. At a median follow-up of 6 (1–60) months, one patient suffered recurrent hematuria requiring a secondary stent graft placement 26 months after the initial treatment. During follow-up, five patients died of the underlying disease (43, 66, 105, and 183 and 274 days after the last procedure).ConclusionPercutaneous balloon-expandable stent graft placement in UAF is a safe and effective treatment option. Implantation of stent grafts should be considered as treatment of choice in UAF.« less

  3. Metal versus plastic stents for drainage of malignant biliary obstruction before primary surgical resection.

    PubMed

    Song, Tae Jun; Lee, Jae Hoon; Lee, Sang Soo; Jang, Ji Woong; Kim, Jung Wook; Ok, Tae Jin; Oh, Dong Wook; Park, Do Hyun; Seo, Dong Wan; Lee, Sung Koo; Kim, Myung-Hwan; Kim, Song Cheol; Kim, Chul Nam; Yun, Sung Cheol

    2016-11-01

    Preoperative biliary drainage (PBD) with stent placement has been commonly used for patients with malignant biliary obstruction. In PBD, the placement of fully covered self-expandable metal stents (FCSEMSs) may provide better patency duration and a lower incidence of cholangitis compared with plastic stents. We aimed to evaluate which type of stent showed better outcomes in PBD. In this multicenter, prospective randomized trial, we compared PBD with FCSEMSs versus plastic stents in 86 patients with malignant biliary obstruction between January 2012 and December 2014. Patients with obstructive jaundice were randomly assigned to undergo PBD either with plastic stents or FCSEMS placement. Baseline characteristics were not significantly different between the 2 groups. Endoscopic stent placement was technically successful in all patients. Procedure-related adverse events were not significantly different between the 2 groups (plastic vs FCSEMS group; 16.3% vs 16.3%, P = 1.0). Reintervention was required in 16.3% of the plastic stent group and 14.0% of the FCSEMS group (P = .763). The interval to surgery after PBD (plastic vs FCSEMS group; 14.2 ± 8.3 vs 12.3 ± 6.9 days, P = .426) was not significantly different between groups. Surgery-related adverse events occurred in 43.6% of the plastic stent group and 40.0% of the FCSEMS group (P = .755). In patients with resectable malignant biliary obstruction, the outcomes of PBD with plastic stents and FCSEMSs were similar. Considering the cost-effectiveness, PBD with plastic stents may be preferable to FCSEMS placement. (Clinical trial registration number: NCT01789502.). Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  4. True double bifurcation lesions: new application of the self-expandable Axxess stent and review of literature with dedicated bifurcation devices.

    PubMed

    Borgia, Francesco; Niglio, Tullio; De Luca, Nicola; Di Serafino, Luigi; Esposito, Giovanni; Trimarco, Bruno; Cirillo, Plinio

    2018-04-21

    Complex coronary artery bifurcation lesions occurred in hard clinical scenarios, such as acute coronary syndromes, may represent a challenge for interventional cardiologists, with not-defined general consensus on treatment. Even if provisional stenting is the most common option used to restore rapidly the coronary branches flow, improvements in industrial technologies and design of new dedicated bifurcation devices might open new modalities of treatment in these complex cases. The Axxess stent (Biosensors Europe SA, Morges, Switzerland) is a self-expanding biolimus-eluting conical V-shape stent, specifically designed to treat "easily" coronary artery bifurcation lesions, with reported favorable long-term clinical results in stable patients compared to a provisional technique. We report for the first time the feasibility to use this device in a case of "true double coronary bifurcation lesion" occurred in the context of acute coronary syndrome. Moreover, we reviewed studies with bifurcation dedicated devices and available cases of "true double bifurcation lesions", underlying advantages/disadvantages of using one device over the others during acute coronary syndrome. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Self-expandable metallic stents in the treatment of post-esophagogastrostomy/post-esophagoenterostomy fistula.

    PubMed

    Nowakowski, P; Ziaja, K; Ludyga, T; Kuczmik, W; Biolik, G; Cwik, P; Ziaja, D

    2007-01-01

    Esophageus or gaster resection in patients with malignant disease is still a treatment of choice. It is obvious that each surgical procedure in these patients carries some possibility of complications. Esophageo-gastric or esophageo-jejuno anastomosis has a 4-27% frequency of fistula occurrence. All these result in 65% mortality in cases of poorer prognosis. The aim of this paper is not to present all types of complications but to objectively analyse the usefulness of the covered stent placement in the treatment of anastomotic fistulas. We present six patients who were treated for postoperative fistula of esophageo-gastric anastomosis (1 case) or esophageo-jejuno anastomosis (5 cases). All patients were treated with stapler suture for digestive tract reconstruction after malignancy removal during the primary surgical procedure. Signs and symptoms of suture leak between 5-8 days post-surgery were observed. Conservative therapy was not effective. Thus a new method of treatment was employed - covered stent placement. The procedure was performed under X-ray control. In all treated patients there was change for the better and quick reduction of secretion from the fistulas was observed. All patients were discharged from the department after several days and all had survived at 30 days follow-up. Covered esophageal stent placement seems to be a safe and promising method of treatment for patients with anastomotic fistula which significantly reduces mortality and improves quality of live. Our experiences confirms that of other investigators.

  6. Elastic Deformation Properties of Implanted Endobronchial Wire Stents in Benign and Malignant Bronchial Disease: A Radiographic In Vivo Evaluation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hautmann, Hubert; Rieger, Johannes; Huber, Rudolf M.

    1999-03-15

    Purpose: To evaluate the long-term mechanical behavior in vivo of expandable endobronchial wire stents, we imaged three different prostheses in the treatment of tracheobronchial disease. Methods: Six patients with bronchial stenoses (three benign, three malignant) underwent insertion of metallic stents. Two self-expandable Wallstents, two balloon-expandable tantalum Strecker stents and two self-expandable nitinol Accuflex stents were used. Measurements of deformation properties were performed during voluntary cough by means of fluoroscopy, at 1 month and 7-10 months after implantation. The procedures were videotaped, their images digitized and the narrowing of stent diameters calculated at intervals of 20 msec. Results: After stent implantationmore » all patients improved with respect to ventilatory function. Radial stent narrowing during cough reached 53% (Wallstent), 59% (tantalum Strecker stent), and 52% (nitinol Accuflex stent) of the relaxed post-implantation diameter. Stent compression was more marked in benign compared with malignant stenoses. In the long term permanent deformation occurred with the tantalum Strecker stents; the other stents were unchanged. Conclusion: Endobronchial wire stents can be helpful in the treatment of major airway collapse and obstructing bronchial lesions. However, evidence of material fatigue as a possible effect of exposure to recurrent mechanical stress on the flexible mesh tube may limit their long-term use. This seems to be predominantly important in benign bronchial collapse.« less

  7. Recurrent airway obstructions in a patient with benign tracheal stenosis and a silicone airway stent: a case report

    PubMed Central

    Sriram, KB; Robinson, PC

    2008-01-01

    Airway stents (silicone and metal stents) are used to treat patients with benign tracheal stenosis, who are symptomatic and in whom tracheal surgical reconstruction has failed or is not appropriate. However airway stents are often associated with complications such as migration, granuloma formation and mucous hypersecretion, which cause significant morbidity, especially in patients with benign tracheal stenosis and relatively normal life expectancy. We report a patient who had frequent critical airway obstructions over 8 years due to granuloma and mucus hypersecretion in a silicone airway stent. The problem was resolved when the silicone stent was removed and replaced with a covered self expanding metal stent. PMID:18840299

  8. Implantability, Complications, and Follow-Up After Transjugular Intrahepatic Portosystemic Stent-Shunt Creation With the 6F Self-Expanding Sinus-SuperFlex-Visual Stent.

    PubMed

    Spira, Daniel; Wiskirchen, Jakub; Lauer, Ulrich; Ketelsen, Dominik; Nikolaou, Konstantin; Wiesinger, Benjamin

    2016-07-01

    The transjugular intrahepatic portosystemic stent-shunt (TIPSS) builds a shortcut between the portal vein and a liver vein, and represents a sophisticated alternative to open surgery in the management of portal hypertension or its complications. To describe clinical experiences with a low-profile nitinol stent system in TIPSS creation, and to assess primary and long-term success. Twenty-six patients (5 females, 21 males; mean age 54.6 years) were treated using a low-profile 6F self-expanding sinus-SuperFlex-Visual stent system. The indication for TIPSS creation was refractory bleeding in 9 of the 26 patients, refractory ascites in 18 patients, and acute thrombosis of the portal vein confluence in one patient. Portosystemic pressure gradients before and after TIPSS, periprocedural and long-term complications, and the time to orthotopic liver transplantation (OLT) or death were recorded. The portosystemic pressure gradient was significantly reduced, from 20.9 ± 6.3 mmHg before to 8.2 ± 2.3 mmHg after TIPSS creation (P < 0.001). Procedure-related complications included acute tract occlusion (n = 2), liver hematoma (n = 1), hepatic encephalopathy (n = 1), and cardiac failure (n = 1). Three of the 26 patients had late-onset TIPSS occlusion (at 12, 12, and 39 months after TIPSS creation). Three patients died within one week after the procedure due to their poor general condition (multiorgan failure, acute respiratory distress syndrome, necrotizing pancreatitis, and aspiration pneumonia). Another four patients succumbed to their underlying advanced liver disease within one year after TIPSS insertion. Seven patients underwent OLT at a mean time of 9.4 months after TIPSS creation. The sinus-SuperFlex-Visual stent system can be safely deployed as a TIPSS device. The pressure gradient reduction was clinically sufficient to treat the patients' symptoms, and periprocedural complications were due to the TIPSS procedure per se rather than to the particular stent system employed

  9. Clinical evaluation of radiotherapy for advanced esophageal cancer after metallic stent placement

    PubMed Central

    Yu, You-Tao; Yang, Guang; Liu, Yan; Shen, Bao-Zhong

    2004-01-01

    AIM: To evaluate the therapeutic effect of radiotherapy for esophageal cancer after expandable metallic stent placement. METHODS: Ten cases of advanced esophageal cancer were evaluated, 7 having complete obstruction and 3 with digestive-respiratory fistula. Ten nitinol stents were placed at the site of stenosis. Patients were treated with a total dose of 1200 cGy divided into 3 fractions of 400 cGy 4-7 d after stents placement. RESULTS: All the 10 stents were placed successfully at one time. After radiotherapy for advanced esophageal cancer, the survival period of the cases ranged from 14 to 22 mo, with a mean survival of 17 mo. No re-stenosis occurred among all the 10 cases. CONCLUSION: Stent placement combined with radiotherapy for esophageal cancer is helpful to prolong patients’ survival and reduce occurrence of re-stenosis. PMID:15237455

  10. Photodynamic therapy for occluded biliary metal stents

    NASA Astrophysics Data System (ADS)

    Roche, Joseph V. E.; Krasner, Neville; Sturgess, R.

    1999-02-01

    In this abstract we describe the use of photodynamic therapy (PDT) to recanalize occluded biliary metal stents. In patients with jaundice secondary to obstructed metal stents PDT was carried out 72 hours after the administration of m THPC. Red laser light at 652 nm was delivered endoscopically at an energy intensity of 50 J/cm. A week later endoscopic retrograde cholangiogram showed complete recanalization of the metal stent.

  11. Evaluation of the 4-French Pulsar-18 Self-expanding Nitinol Stent in Long Femoropopliteal Lesions.

    PubMed

    Lichtenberg, Michael; Hailer, Birgit; Kaeunicke, Matthias; Stahlhoff, Wilhelm-Friedrich; Boese, Dirk; Breuckmann, Frank

    2014-01-01

    To evaluate the patency and the freedom of target lesion revascularization of the 4-French Pulsar-18 self-expandable (SE) nitinol stent for the treatment of long femoropopliteal occlusive disease in a two-center, prospective, all-comers registry with a follow-up period of 12 months. This registry enrolled 36 patients with symptomatic femoropopliteal long lesions for recanalization and implantation of the 4-French Pulsar-18 SE nitinol stent. Routine follow-up examination including duplex ultrasound was performed after 6 and 12 months. Primary patency was defined as no binary restenosis on duplex ultrasound (Peak systolic velocitiy ration (PSVR) <2.5) and no target lesion revascularization was performed within 12 months' follow-up. No drug-eluting devices were allowed in this registry. Average lesion length of the femoropopliteal segment was 182.3 ± 51.8 mm. Mean stent implantation length was 181.5 ± 35.4 mm. Total occlusion was present in 46 of the 48 (95.8%) treated lesions. Involvement of popliteal segment I-III was present in 3 (6.3%) lesions. The primary patency after 6 and 12 months was 87.5% and 85.4%, respectively. The clinically driven overall freedom from target lesion revascularization (fTLR) was 89.6% after 6 months and 87.5% after 12 months. ABI, pain-free walking distance and Rutherford category, all improved significantly (P < 0.001) after 6 and 12 months. The primary patency rate in patients with diabetes (P = 0.18) and renal insufficiency (P = 0.3) was not significantly lower as compared to the overall primary patency. In this two-center, all-comers registry, the use of the Pulsar-18 SE nitinol stent for endovascular intervention of femoropopliteal disease with a mean lesion length of 182.3 ± 51.8 mm showed promising primary patency and fTLR rates after 6 and 12 months. Diabetes and renal insufficiency had no negative impact on the patency rate.

  12. Comparison of expandable endotracheal stents in the treatment of surgically induced piglet tracheomalacia.

    PubMed

    Mair, E A; Parsons, D S; Lally, K P; Van Dellen, A F

    1991-09-01

    Present surgical alternatives for pediatric tracheobronchomalacia are limited and associated with many potentially undesirable complications. The feasibility of different intraluminal expandable endotracheal stents for the treatment of surgically induced tracheomalacia was analyzed in 27 piglets. A potentially fatal tracheomalacia was surgically created. Either a stainless steel "zig-zag" stent or a woven polymeric stent was then implanted. Tracheal patency, mucosal function, histopathologic respiratory tract changes, and effects of the stent on esophageal motility were evaluated over a 16-week period. Piglets with steel stents uniformly experienced intense inflammation leading to tracheal dysfunction and death. Piglets with polymeric stents experienced minimal respiratory symptoms. Expandable polymeric endotracheal stents alleviate surgically induced piglet tracheomalacia, were easy to insert, allowed for tracheal growth, and reduced the need for high-risk surgical procedures with prolonged ventilatory support.

  13. Evidence-Based Recommendations on Upper Gastrointestinal Tract Stenting: A Report from the Stent Study Group of the Korean Society of Gastrointestinal Endoscopy

    PubMed Central

    Jee, Sam Ryong; Kim, Kyung Ho; Kim, Sang Gyun; Cho, Jun-Hyung

    2013-01-01

    Endoscopic stents have evolved dramatically over the past 20 years. With the introduction of uncovered self-expanding metal stents in the early 1990s, they are primarily used to palliate symptoms of malignant obstruction in patients with inoperable gastrointestinal (GI) cancer. At present, stents have emerged as an effective, safe, and less invasive alternative for the treatment of malignant GI obstruction. Clinical decisions about stent placement should be made based on the exact understanding of the patient's condition. These recommendations based on a critical review of the available data and expert consensus are made for the purpose of providing endoscopists with information about stent placement. These can be helpful for management of patients with inoperable cancer or various nonmalignant conditions in the upper GI tract. PMID:23964331

  14. [Fine mesh metal endoprostheses for treatment of extensive cervical and intrathoracic tracheomalacia].

    PubMed

    Wilmes, E; Berger, H; Dienemann, H; Jolk, A

    1994-01-01

    The treatment of tracheal stenoses caused by tracheomalacia is mainly carried out by means of sleeve resection, tracheopexy with ring support or other tracheoplastic operative procedures. If patients cannot be treated by surgical operative strategies, conventional stents are usually used to dilate the trachea. The use of a self-expanding elastic metal prosthesis in 5 patients with tracheal airway obstruction caused by tracheomalacia proved to be a true alternative in the therapy of tracheobronchial stenoses. We report on the long term use of 5 patients with tracheal stenoses treated by implantation of elastic metal wallstents. The implantation of the stents resulted in immediate improvement in respiratory function in all 5 patients. None of the patients experienced complications secondary to the stent placement. The stents were well tolerated (long-time follow-up 26 months). The implantation of self-expanding metal stents type "wallstent" seems to offer alternative possibilities for the treatment of tracheomalacia.

  15. A systematic review of biodegradable biliary stents: promising biocompatibility without stent removal.

    PubMed

    Siiki, Antti; Sand, Juhani; Laukkarinen, Johanna

    2018-05-18

    Biodegradable self-expanding stents are an emerging alternative to standard biliary stents as the development of endoscopic insertion devices advances. The aim was to systematically review the existing literature on biodegradable biliary stents. In-vivo studies on the use of biodegradable stents in the biliary duct were systematically reviewed from 1990 to 2017. Despite extensive research on the biocompatibility of stents, the experience so far on their clinical use is limited. A few favorable reports have recently been presented on endoscopically and percutaneously inserted self-expanding biodegradable polydioxanone stents in benign biliary strictures. Another potential indication appears to be postcholecystectomy leak of the cystic duct. The main benefit of biodegradable stents is that stent removal can be avoided. The biocompatibility of the current biodegradable stent materials, most prominently polydioxanone, is well documented. In the few studies currently available, biodegradable stents are reported to be feasible and safe, also in humans. The initial results of the endoscopic use of these stents in benign biliary stricture management and for treating postcholecystectomy bile leaks are promising. Further controlled studies on long-term clinical results and cost-effectiveness are needed.

  16. A Double-Layered Covered Biliary Metal Stent for the Management of Unresectable Malignant Biliary Obstruction: A Multicenter Feasibility Study.

    PubMed

    Park, Jin-Seok; Jeong, Seok; Lee, Don Haeng; Moon, Jong Ho; Lee, Kyu Taek; Dong, Seok Ho

    2016-11-15

    The covered self-expandable metal stent (CMS) was developed to prevent tumor ingrowth-induced stent occlusion during the treatment of malignant biliary obstruction. However, complications such as cholecystitis, pancreatitis, and stent migration can occur after the endoscopic insertion of CMSs. The aim of the present study was to assess the efficacy and safety of a double-layered CMS (DCMS) for the management of malignant bile duct obstruction. DCMSs were endoscopically introduced into 59 patients with unresectable malignant extrahepatic biliary obstruction at four tertiary referral centers, and the patient medical records were retrospectively reviewed. Both the technical and functional success rates were 100%. Procedure-related complications including pancreatitis, cholangitis, stent migration, and liver abscess occurred in five patients (8.5%). The median follow-up period was 265 days (range, 31 to 752 days). Cumulative stent patency rates were 68.2% and 40.8% at 6 and 12 months, respectively. At the final follow-up, the rate of stent occlusion was 33.9% (20/59), and the median stent patency period was 276 days (range, 2 to 706 days). The clinical outcomes of DCMSs were comparable to the outcomes previously reported for CMSs with respect to stent patency period and complication rates.

  17. Stent thrombosis with drug-eluting and bare-metal stents: evidence from a comprehensive network meta-analysis.

    PubMed

    Palmerini, Tullio; Biondi-Zoccai, Giuseppe; Della Riva, Diego; Stettler, Christoph; Sangiorgi, Diego; D'Ascenzo, Fabrizio; Kimura, Takeshi; Briguori, Carlo; Sabatè, Manel; Kim, Hyo-Soo; De Waha, Antoinette; Kedhi, Elvin; Smits, Pieter C; Kaiser, Christoph; Sardella, Gennaro; Marullo, Antonino; Kirtane, Ajay J; Leon, Martin B; Stone, Gregg W

    2012-04-14

    The relative safety of drug-eluting stents and bare-metal stents, especially with respect to stent thrombosis, continues to be debated. In view of the overall low frequency of stent thrombosis, large sample sizes are needed to accurately estimate treatment differences between stents. We compared the risk of thrombosis between bare-metal and drug-eluting stents. For this network meta-analysis, randomised controlled trials comparing different drug-eluting stents or drug-eluting with bare-metal stents currently approved in the USA were identified through Medline, Embase, Cochrane databases, and proceedings of international meetings. Information about study design, inclusion and exclusion criteria, sample characteristics, and clinical outcomes was extracted. 49 trials including 50,844 patients randomly assigned to treatment groups were analysed. 1-year definite stent thrombosis was significantly lower with cobalt-chromium everolimus eluting stents (CoCr-EES) than with bare-metal stents (odds ratio [OR] 0·23, 95% CI 0·13-0·41). The significant difference in stent thrombosis between CoCr-EES and bare-metal stents was evident as early as 30 days (OR 0·21, 95% CI 0·11-0·42) and was also significant between 31 days and 1 year (OR 0·27, 95% CI 0·08-0·74). CoCr-EES were also associated with significantly lower rates of 1-year definite stent thrombosis compared with paclitaxel-eluting stents (OR 0·28, 95% CI 0·16-0·48), permanent polymer-based sirolimus-eluting stents (OR 0·41, 95% CI 0·24-0·70), phosphorylcholine-based zotarolimus-eluting stents (OR 0·21, 95% CI 0·10-0·44), and Resolute zotarolimus-eluting stents (OR 0·14, 95% CI 0·03-0·47). At 2-year follow-up, CoCr-EES were still associated with significantly lower rates of definite stent thrombosis than were bare-metal (OR 0·35, 95% CI 0·17-0·69) and paclitaxel-eluting stents (OR 0·34, 95% CI 0·19-0·62). No other drug-eluting stent had lower definite thrombosis rates compared with bare-metal

  18. Randomized trial in malignant biliary obstruction: Plastic vs partially covered metal stents

    PubMed Central

    Moses, Peter L; AlNaamani, Khalid M; Barkun, Alan N; Gordon, Stuart R; Mitty, Roger D; Branch, M Stanley; Kowalski, Thomas E; Martel, Myriam; Adam, Viviane

    2013-01-01

    AIM: To compare efficacy and complications of partially covered self-expandable metal stent (pcSEMS) to plastic stent (PS) in patients treated for malignant, infrahilar biliary obstruction. METHODS: Multicenter prospective randomized clinical trial with treatment allocation to a pcWallstent® (SEMS) or a 10 French PS. Palliative patients aged ≥ 18, for infrahilar malignant biliary obstruction and a Karnofsky performance scale index > 60% from 6 participating North American university centers. Primary endpoint was time to stent failure, with secondary outcomes of death, adverse events, Karnofsky performance score and short-form-36 scale administered on a three-monthly basis for up to 2 years. Survival analyses were performed for stent failure and death, with Cox proportional hazards regression models to determine significant predictive characteristics. RESULTS: Eighty-five patients were accrued over 37 mo, 42 were randomized to the SEMS group and 83 patients were available for analyses. Time to stent failure was 385.3 ± 52.5 d in the SEMS and 153.3 ± 19.8 d in the PS group, P = 0.006. Time to death did not differ between groups (192.3 ± 23.4 d for SEMS vs 211.5 ± 28.0 d for PS, P = 0.70). The only significant predictor was treatment allocation, relating to the time to stent failure (P = 0.01). Amongst other measured outcomes, only cholangitis differed, being more common in the PS group (4.9% vs 24.5%, P = 0.029). The small number of patients in follow-up limits longitudinal assessments of performance and quality of life. From an initially planned 120 patients, only 85 patients were recruited. CONCLUSION: Partially covered SEMS result in a longer duration till stent failure without increased complication rates, yet without accompanying measurable benefits in survival, performance, or quality of life. PMID:24379581

  19. Tracheal stricture and fistula: management with a barbed silicone-covered retrievable expandable nitinol stent.

    PubMed

    Kim, Yong Hee; Shin, Ji Hoon; Song, Ho-Young; Kim, Jin Hyoung

    2010-02-01

    The purpose of this study was to evaluate the safety and effectiveness of a barbed silicone-covered retrievable expandable nitinol stent in preventing stent migration in patients with tracheal strictures or fistulas. Under fluoroscopic guidance, barbed silicone-covered retrievable expandable nitinol stents were placed in 15 patients with tracheal strictures, two patients with fistulas, two patients with combined strictures and fistulas, and one patient with variable extrathoracic airway obstruction. The three pairs of barbs were attached to the external stent surface at the middle of the stent at equal intervals. Technical success, improvement in respiratory status, complications, and related interventions were evaluated. The technical success rate was 100%, and respiratory status improved or the fistula closed in all 20 patients. Complications included sputum retention (three patients), tumor overgrowth (three patients), pain (one patient), and granulation tissue formation (one patient). No stent migration occurred, even in the three patients without fixed strictures. Four stents subsequently were removed because of complications, and one stent was removed because the patient's condition improved. Stent removal was not difficult and was uneventful. The silicone membranes and barbs of the removed stents were intact. Use of a barbed silicone-covered retrievable expandable nitinol stent relieves dyspnea and facilitates fistula closure in patients with benign or malignant tracheal strictures or fistulas. The barbed design of the stent is important in preventing migration.

  20. Endoscopic biliary stent insertion through specialized duodenal stent for combined malignant biliary and duodenal obstruction facilitated by stent or PTBD guidance.

    PubMed

    Lee, Jong Jin; Hyun, Jong Jin; Choe, Jung Wan; Lee, Dong-Won; Kim, Seung Young; Jung, Sung Woo; Jung, Young Kul; Koo, Ja Seol; Yim, Hyung Joon; Lee, Sang Woo

    2017-11-01

    Endoscopic stenting for combined malignant biliary and duodenal obstruction is technically demanding. However, this procedure can be facilitated when there is guidance from previously inserted stent or PTBD tube. This study aimed to evaluate the feasibility and clinical success rate of endoscopic placement of biliary self-expandable metal stent (SEMS) through duodenal SEMS in patients with combined biliary and duodenal obstruction due to inoperable or metastatic periampullary malignancy. A total of 12 patients with combined malignant biliary and duodenal stricture underwent insertion of biliary SEMS through the mesh of specialized duodenal SEMS from July 2012 to October 2016. Technical and clinical success rate, adverse events and survival after completion of SEMS insertion were evaluated. The duodenal strictures were located in the first portion of the duodenum in four patients (Type I), in the second portion in three patients (Type II), and in the third portion in five patients (Type III). Technical success rate of combined metallic stenting was 91.7%. Insertion of biliary SEMS was guided by previously inserted biliary SEMS in nine patients, plastic stent in one patient, and PTBD in two patients. Clinical success rate was 90.9%. There were no early adverse events after the procedure. Mean survival period after combined metallic stenting was 91.9 days (range: 15-245 days). Endoscopic placement of biliary SEMS through duodenal SEMS is feasible with high success rates and relatively easy when there is guidance. This method can be a good alternative for palliation in patients with combined biliary and duodenal obstruction.

  1. Covered Metallic Stents With an Anti-Migration Design vs. Uncovered Stents for the Palliation of Malignant Gastric Outlet Obstruction: A Multicenter, Randomized Trial

    PubMed Central

    Lee, Hyuk; Min, Byung-Hoon; Lee, Jeong Hoon; Shin, Cheol Min; Kim, Younjoo; Chung, Hyunsoo; Lee, Sang Hyub

    2015-01-01

    OBJECTIVES: Previous studies reported comparable stent patency between covered self-expandable metallic stents (SEMS) and uncovered SEMS (UCS) for palliation of malignant gastric outlet obstruction (GOO). The aim of this study was to evaluate the efficacy and safety of the newly developed WAVE-covered SEMS (WCS), which has an anti-migration design, compared with UCS in gastric cancer patients with symptomatic GOO. METHODS: A total of 102 inoperable gastric cancer patients with symptomatic GOO were prospectively enrolled from five referral centers and randomized to undergo UCS or WCS placement. Stent patency and recurrence of obstructive symptoms were assessed at 8 weeks and 16 weeks after stent placement. RESULTS: At the 8-week follow-up, both stent patency rates (72.5% vs. 62.7%) and re-intervention rates (19.6% vs. 19.6%) were comparable between the WCS and the UCS groups. Both stent stenosis (2.4% vs. 8.1%) and migration rates (9.5% vs. 5.4%) were comparable between WCS and UCS groups. At the 16-week follow-up, however, the WCS group had a significantly higher stent patency rate than the UCS group (68.6% vs. 41.2%). Re-intervention rates in the WCS and UCS groups were 23.5% and 39.2%, respectively. Compared with the UCS group, the WCS group had a significantly lower stent restenosis rate (7.1% vs. 37.8%) and a comparable migration rate (9.5% vs. 5.4%). Overall stent patency was significantly longer in the WCS group than in the UCS group. No stent-associated significant adverse events occurred in either the WCS or UCS groups. In the multivariate analysis, WCS placement and chemotherapy were identified as independent predictors of 16-week stent patency. CONCLUSIONS: WCS group showed comparable migration rate and significantly more durable long-term stent patency compared with UCS group for the palliation of GOO in patients with inoperable gastric cancer. PMID:26372507

  2. Resolution of Metallic Biliary Stent Allergic Reaction After Partial Stent Removal in a Patient with Nickel Sensitivity.

    PubMed

    Esparaz, Anthony M; Ahmed, Muneeb

    2017-07-01

    Local and systemic reactions to implanted metallic devices, particularly to those containing nickel, are well documented. Metal ions are released due to exposure of the metal to blood, proteins, other body fluids, and sheer mechanical stress. Metal ions then complex with native proteins and become antigens, which can elicit hypersensitivity reactions. Another case report depicts a specific allergic complication (early stent occlusion) related to metallic biliary stent implantation. We present a case of allergic symptoms, associated with eating, in a patient who developed nickel sensitivity after biliary metal stent placement confirmed by allergic skin testing to the same metallic biliary stent placed one year earlier. Symptoms resolved following partial removal of the non-epithelialized portion of the biliary stent.

  3. Aspirin Use Is Associated With Reduced Risk of Occlusion of Metallic Biliary Stents.

    PubMed

    Jang, Sunguk; Stevens, Tyler; Parsi, Mansour A; Lopez, Rocio; Vargo, John J

    2017-03-01

    Biliary self-expandable metallic stents (SEMSs) are widely used to treat malignant and benign conditions of bile duct. Despite their lower rate of occlusion and longer patency than plastic stents, SEMSs still have significant rates of occlusion. We aimed to identify factors associated with occlusion of biliary SEMS. We performed a retrospective study of consecutive patients who underwent endoscopic retrograde cholangiopancreatography with biliary SEMS placement at the Cleveland Clinic Foundation from March 2011 to April 2016. We collected clinical, endoscopic, radiographic, and surgical data from medical records and performed multivariable analysis to identify factors associated with SEMS patency. Subjects that received minimal daily dose of 81 mg at the time of stent placement until the end of follow-up were assigned to the aspirin exposure group (n = 157) and compared with subjects with no aspirin exposure (n = 436). Patients were followed for a median 81 days. The primary outcome was hazard ratio for SEMS occlusion requiring an interventional maneuver for biliary drainage. We analyzed data from patients receiving a total of 593 biliary SEMS for treatment of malignant and benign conditions of bile duct. Stent occlusion was observed in 126 cases. Multivariable analysis showed that daily use of aspirin (81 mg or more) was associated with 51% lower risk of stent occlusion than in patients without daily use of aspirin (hazard ratio, 0.49; 95% confidence interval, 0.32-0.75). Furthermore, SEMSs had a longer duration of stent patency in patients in the aspirin exposure group (434.4 days) versus the no aspirin exposure group (339.9 days) (P < .001). Stricture location limited to distal bile duct (in comparison with strictures involving proximal extrahepatic duct) was associated with lower risk of stent occlusion (hazard ratio, 0.39; 95% CI, 0.22-0.71). In an analysis of a large cohort of subjects with metallic biliary stent placement for malignant and benign

  4. Novel 3D-CT evaluation of carotid stent volume: greater chronological expansion of stents in patients with vulnerable plaques.

    PubMed

    Itami, Hisakazu; Tokunaga, Koji; Okuma, Yu; Hishikawa, Tomohito; Sugiu, Kenji; Ida, Kentaro; Date, Isao

    2013-09-01

    Although self-expanding carotid stents may dilate gradually, the degrees of residual stenosis have been quantified by the NASCET criteria, which is too simple to reflect the configuration of the stented artery. We measured the volumes of the stent lumens chronologically by 3D-CT in patients after carotid artery stenting (CAS), and analyzed the correlations between the volume change and medical factors. Fourteen patients with carotid artery stenosis were treated using self-expanding, open-cell stents. All patients underwent preoperative plaque MRI (magnetization-prepared rapid acquisition gradient-echo, MPRAGE) and chronological 3D-CT examinations of their stents immediately after their placement and 1 day, 1 week, and 1 month after the procedure. The volume of the stent lumen was measured using a 3D workstation. The correlations between stent volume and various factors including the presence of underlying diseases, plaque characteristics, and the results of the CAS procedure were analyzed. Stent volume gradually increased in each case and had increased by 1.04-1.55 (mean, 1.25)-fold at 1 postoperative month. The presence of underlying medical diseases, plaque length, the degree of residual stenosis immediately after CAS, and plaque calcification did not have an impact on the change in stent volume. On the other hand, the stent volume increase was significantly larger in the patients with vulnerable plaques that demonstrated high MPRAGE signal intensity (P < 0.05). A 3D-CT examination is useful for precisely measuring stent volume. Self-expanding stents in carotid arteries containing vulnerable plaques expand significantly more than those without such plaques in a follow-up period.

  5. Long term impact of balloon post-dilatation on neointimal formation: an experimental comparative study between second-generation self-expanding versus balloon-expandable stent technologies.

    PubMed

    Aboodi, Michael S; Milewski, Krzysztof; Tellez, Armando; Cheng, Yanping; Yi, Geng-Hua; Kaluza, Greg L; Granada, Juan F

    2014-02-15

    Background: Self-expanding stents (SES) are reemerging as therapeutic alternatives to treat coronary artery disease. It has been proposed that SES can improve clinical outcomes by inducing less injury at implantation and achieving better vessel wall apposition.To date, little data exists comparing the vascular response to both methods of deployment in a controlled experimental setting. Objective: To quantify differences in vascular injury and healing between second-generation SES and balloon-expandable stents (BES) and the effects of balloon post-dilatation in a porcine coronary model. Methods: Seventy-five bare SES (AXXESS or vProtect) and 42 BES (Vision) were implanted in porcine coronaries. A subset of these received balloon post-dilatation(SES 1 D 5 22, BES 1 D 5 20). Follow-up was scheduled at 30 (BES 5 10, BES 1 D 56, SES 5 19, SES 1 D 5 8), 90 (BES 5 6, BES 1 D 5 8, SES 5 19, SES 1 D 5 8), and 180 days (BES 5 6, BES 1 D 5 6, SES 5 15, SES 1 D 5 6). Results: In vivo imaging and histological analysis showed that neointimal formation peaks early (30 days) in BES. Conversely, for SES, the peak occurred later (90 days). However, the neointimal formation achieved in either group equalized at 180 days. For SES, post-dilatation shortened the peak of neointimal formation to 30 days. Conversely, for BES, post-dilatation delayed the peak of neointimal formation to 90 days. At 30 days, histology showed that SES had significantly less injury. However, at 90 days, injury scores tended to be higher for SES. By 180 days, injury scores were comparable between both groups. Conclusions: The mechanism of stent expansion influences the degree of vascular injury and healing. The synergistic use of balloon post dilatation changes the dynamics of healing and may impact the potential beneficial effects inherent to SES technologies.

  6. Antireflux Metal Stent as a First-Line Metal Stent for Distal Malignant Biliary Obstruction: A Pilot Study.

    PubMed

    Hamada, Tsuyoshi; Isayama, Hiroyuki; Nakai, Yousuke; Togawa, Osamu; Takahara, Naminatsu; Uchino, Rie; Mizuno, Suguru; Mohri, Dai; Yagioka, Hiroshi; Kogure, Hirofumi; Matsubara, Saburo; Yamamoto, Natsuyo; Ito, Yukiko; Tada, Minoru; Koike, Kazuhiko

    2017-01-15

    In distal malignant biliary obstruction, an antireflux metal stent (ARMS) with a funnel-shaped valve is effective as a reintervention for metal stent occlusion caused by reflux. This study sought to evaluate the feasibility of this ARMS as a first-line metal stent. Patients with nonresectable distal malignant biliary obstruction were identified between April and December 2014 at three Japanese tertiary centers. We retrospectively evaluated recurrent biliary obstruction and adverse events after ARMS placement. In total, 20 consecutive patients were included. The most common cause of biliary obstruction was pancreatic cancer (75%). Overall, recurrent biliary obstruction was observed in seven patients (35%), with a median time to recurrent biliary obstruction of 246 days (range, 11 to 246 days). Stent occlusion occurred in five patients (25%), the causes of which were sludge and food impaction in three and two patients, respectively. Stent migration occurred in two patients (10%). The rate of adverse events associated with ARMS was 25%: pancreatitis occurred in three patients, cholecystitis in one and liver abscess in one. No patients experienced nonocclusion cholangitis. The ARMS as a first-line biliary drainage procedure was feasible. Because the ARMS did not fully prevent stent dysfunction due to reflux, further investigation is warranted.

  7. Evaluation of the short- and long-term effectiveness and safety of fully covered self-expandable metal stents for drainage of pancreatic fluid collections: results of a Spanish nationwide registry.

    PubMed

    Vazquez-Sequeiros, Enrique; Baron, Todd H; Pérez-Miranda, Manuel; Sánchez-Yagüe, Andres; Gornals, Joan; Gonzalez-Huix, Ferran; de la Serna, Carlos; Gonzalez Martin, Juan Angel; Gimeno-Garcia, Antonio Z; Marra-Lopez, Carlos; Castellot, Ana; Alberca, Fernando; Fernandez-Urien, Ignacio; Aparicio, Jose Ramon; Legaz, Maria Luisa; Sendino, Oriol; Loras, Carmen; Subtil, Jose Carlos; Nerin, Juan; Perez-Carreras, Mercedes; Diaz-Tasende, Jose; Perez, Gustavo; Repiso, Alejandro; Vilella, Angels; Dolz, Carlos; Alvarez, Alberto; Rodriguez, Santiago; Esteban, Jose Miguel; Juzgado, Diego; Albillos, Agustin

    2016-09-01

    Initial reports suggest that fully covered self-expandable metal stents (FCSEMSs) may be better suited for drainage of dense pancreatic fluid collections (PFCs), such as walled-off pancreatic necrosis. The primary aim was to analyze the effectiveness and safety of FCSEMSs for drainage of different types of PFCs in a large cohort. The secondary aim was to investigate which type of FCSEMS is superior. This was a retrospective, noncomparative review of a nationwide database involving all hospitals in Spain performing EUS-guided PFC drainage. From April 2008 to August 2013, all patients undergoing PFC drainage with an FCSEMS were included in a database. The main outcome measurements were technical success, short-term (2 weeks) and long-term (6 months) effectiveness, adverse events, and need for surgery. The study included 211 patients (pseudocyst/walled-off pancreatic necrosis, 53%/47%). The FCSEMSs used were straight biliary (66%) or lumen-apposing (34%). Technical success was achieved in 97% of patients (95% confidence interval [CI], 93%-99%). Short-term- and long-term clinical success was obtained in 94% (95% CI, 89%-97%) and 85% (95% CI, 79%-89%) of patients, respectively. Adverse events occurred in 21% of patients (95% CI, 16%-27%): infection (11%), bleeding (7%), and stent migration and/or perforation (3%). By multivariate analysis, patient age (>58 years) and previous failed drainage were the most important factors associated with negative outcome. An FCSEMS is effective and safe for PFC drainage. Older patients with a history of unsuccessful drainage are more likely to fail EUS-guided drainage. The type of FCSEMS does not seem to influence patient outcome. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  8. A Pilot Study of Open Venous Revascularization using Expandable PTFE Stent Grafts in a Porcine (Sus scrofa) Model

    DTIC Science & Technology

    2017-05-23

    expandable stent -grafts that are designed to expand within a vessel to cover an injury or open a blockage. Methods: 3 Yorkshire cross swine were...expandable PTFE stent graft was deployed into the vessel in an open direct fashion. The swine were awoken and allowed to ambulate. At 72 hours, conduit...hours, all stents were patent on venography. Conclusion: Direct site endovascular repair of venous injuries utilizing expandable PTFE stent grafts is a

  9. [Evaluation of stents in treating childhood benign esophageal strictures].

    PubMed

    Reinshagen, K; Kähler, G; Manegold, B C; Waag, K-L

    2009-01-01

    Esophageal stenting is a popular of treatment of esophageal strictures in adults. It has also been described for children with benign strictures who did not respond to standard dilatation therapy. The aim of the study was to evaluate weather esophageal stents could be used safely and effectively in the treatment of benign esophageal strictures in children. From 1993 to 2005 stenting therapy was performed in 12 children with complicated esophageal strictures. Etiologies of the strictures were caustic burns in 9 patients, postoperative strictures due to complicated esophageal atresia in 2 patients and iatrogenic esophageal injury in 1 patient. Esophageal silicon tubi, covered retrievable expandable nitinol and plastic stents were placed endoscopically. The clinical course and the long term follow up were evaluated retrospectively The stents and tubi were placed in all patients without complications and were later removed successfully. 6 patients were treated with a self expanding plastic stent. The plastic stents showed a distinct tendency to migrate but in 5/6 patients esophageal stricture was treated successfully. 3 patients were treated by a covered self expanding nitinol stent. No migration occurred. One patient was asymptomatic after therapy, one required further dilatation therapy and the third had esophageal resection. 3 patients were treated by esophageal tubi. 2 patients required surgery in the follow up, one patient is asymptomatic. The use of stenting devices in children to treat benign esophageal strictures is safe and efficient. The self expanding plastic stents had the best long term results but required high compliance of parents and children due to the tendency of stent migration. Self expanding nitinol stents are more traumatic at the extraction procedure and are useful in patients with low compliance. Recurrence of strictures occurred most often after esophageal tubi possibly due to the lack of radial expansion.

  10. Esophageal leiomyoma in a dog causing esophageal distension and treated by transcardial placement of a self-expanding, covered, nitinol esophageal stent.

    PubMed

    Robin, Elisabeth M; Pey, Pascaline B; de Fornel-Thibaud, Pauline; Moissonnier, Pierre H M; Freiche, Valérie

    2018-02-01

    CASE DESCRIPTION A 10-year-old spayed female Rottweiler was referred for evaluation because of a 2-month history of regurgitation and weight loss, despite no apparent change in appetite. The dog had received antiemetic and antacid treatment, without improvement. CLINICAL FINDINGS Physical examination revealed a low body condition score (2/5), but other findings were unremarkable. Diffuse, global esophageal dilatation was noted on plain thoracic radiographs, and normal motility was confirmed through videofluoroscopic evaluation of swallowing. Transhepatic ultrasonographic and CT examination revealed a circumferential, intraparietal lesion in the distal portion of the esophagus causing distal esophageal or cardial subobstruction and no metastases. Incisional biopsy of the lesion was performed, and findings of histologic examination supported a diagnosis of esophageal leiomyoma. TREATMENT AND OUTCOME In view of numerous possible complications associated with esophageal surgery, the decision was made to palliatively treat the dog by transcardial placement of a self-expanding, covered, nitinol esophageal stent under endoscopic guidance. Two weeks after stent placement, radiography revealed complete migration of the stent into the gastric lumen. Gastrotomy was performed, and the stent was replaced and fixed in place. Twenty-four months after initial stent placement, the dog had a healthy body condition and remained free of previous clinical signs. CLINICAL RELEVANCE Diffuse benign muscular neoplasia should be considered as a differential diagnosis for acquired esophageal dilatation in adult and elderly dogs. In the dog of this report, transcardial stent placement resulted in resolution of the clinical signs, with no apparent adverse effect on digestive function. The described procedure could be beneficial for nonsurgical treatment of benign esophageal tumors in dogs.

  11. A practical method to rapidly dissolve metallic stents.

    PubMed

    Bradshaw, Scott H; Kennedy, Lloyd; Dexter, David F; Veinot, John P

    2009-01-01

    Metallic stents are commonly used in many clinical applications including peripheral vascular disease intervention, biliary obstruction, endovascular repair of aneurysms, and percutaneous coronary interventions. In the examination of vascular stent placement, it is important to determine if the stent is open or has become obstructed. This is increasingly important in the era of drug-eluting stent usage in coronary arteries. We describe a practical, rapid and cost-effective method to dissolve most metallic stents leaving the vascular and luminal tissues intact. This practical method may replace the laborious and expensive plastic embedding methods currently utilized.

  12. Use of a lumen-apposing metal stent to treat GI strictures (with videos).

    PubMed

    Irani, Shayan; Jalaj, Sujai; Ross, Andrew; Larsen, Michael; Grimm, Ian S; Baron, Todd H

    2017-06-01

    Benign GI strictures occur typically in the esophagus and pyloric channel but can occur anywhere in the GI tract and at anastomotic sites. Such strictures can be treated with dilation, incisional therapy, steroid injection, and stents. Our aim was to describe the use of a lumen-apposing metal stent (LAMS) to treat short, benign GI strictures. Consecutive patients who underwent LAMS placement for various benign strictures at 2 tertiary care centers from August 2014 to November 2015 were reviewed retrospectively. The main outcome measures were technical success, clinical success, stent migration, and adverse events. Twenty-five patients (7 males, 18 females) with a median age of 54 years (33-85 years) underwent 28 LAMS placements to treat various benign strictures. The location of the strictures included esophagogastric anastomoses (n=4), gastrojejunal anastomoses (n=13), pylorus (n=6), vertical banded gastroplasty (n=1), and ileocolonic anastomosis (n=1). Twenty patients had been previously treated with dilation alone (9 patients with ≥3 dilations), 11 patients with dilation and steroid injection, 2 patients with additional needle-knife therapy, and 1 patient with placement of a traditional fully covered self-expandable metal stent. A 15-mm internal diameter LAMS was placed in all patients; 3 patients had been treated previously with a 10-mm LAMS. Technical success was achieved in all patients, whereas clinical success was achieved in 15 of 25 patients (60%) who completed a minimum of 6 months of follow-up after placement. Median stent dwell time was 92 days (range, 3-273 days). Stent migration was seen in 2 of 28 stent placements (7%). Four of 25 patients (16%) developed 5 moderate adverse events (pain requiring removal, 2; new stricture formation, 2; bleeding, 1). Median follow-up was 301 days after stent placement. Study limitations include the small, select group of patients, the retrospective study design, and short follow-up. LAMS placement for benign GI

  13. Treatment of tracheomalacia with Palmaz stent: a case report.

    PubMed

    Inan, Mustafa; Ayvaz, Süleyman; Basaran, Umit Nusret

    2005-01-01

    Tracheomalacia is a potentially life-threatening clinical problem. The expandable Palmaz stent can be used for the treatment of tracheomalacia. We describe a female infant with tracheomalacia who showed respiratory distress the day after birth. Tracheomalacia was diagnosed by bronchoscopic examination, computed tomography and bronchography. At 75 days of age, an expandable metallic stent (Palmaz stent) was inserted into the trachea under fluoroscopic control. The patient's respiratory status improved rapidly. Bronchoscopic examination 6 months after the insertion did not show any granulation tissue. However, in bronchoscopic examination carried out two years later, we detected invasion of the Palmaz stent to the trachea and development of granulation tissue. We think that expandable metallic stent placement should be considered in patients who show intractable respiratory symptoms caused by tracheomalacia in the earlier stages of the treatment. But long-term complications of this procedure are crucial.

  14. Understanding the requirements of self-expandable stents for heart valve replacement: Radial force, hoop force and equilibrium.

    PubMed

    Cabrera, María Sol; Oomens, Cees W J; Baaijens, Frank P T

    2017-04-01

    A proper interpretation of the forces developed during stent crimping and deployment is of paramount importance for a better understanding of the requirements for successful heart valve replacement. The present study combines experimental and computational methods to assess the performance of a nitinol stent for tissue-engineered heart valve implantation. To validate the stent model, the mechanical response to parallel plate compression and radial crimping was evaluated experimentally. Finite element simulations showed good agreement with the experimental findings. The computational models were further used to determine the hoop force on the stent and radial force on a rigid tool during crimping and self-expansion. In addition, stent deployment against ovine and human pulmonary arteries was simulated to determine the hoop force on the stent-artery system and the equilibrium diameter for different degrees of oversizing. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Impact of stent strut design in metallic stents and biodegradable scaffolds.

    PubMed

    Foin, Nicolas; Lee, Renick D; Torii, Ryo; Guitierrez-Chico, Juan Luis; Mattesini, Alessio; Nijjer, Sukhjinder; Sen, Sayan; Petraco, Ricardo; Davies, Justin E; Di Mario, Carlo; Joner, Michael; Virmani, Renu; Wong, Philip

    2014-12-20

    Advances in the understanding of healing mechanisms after stent implantation have led to the recognition of stent strut thickness as an essential factor affecting re-endothelialization and overall long term vessel healing response after Percutaneous Coronary Interventions (PCI). Emergence of Drug-eluting stents (DESs) with anti-proliferative coating has contributed to reducing the incidence of restenosis and Target Lesion Revascularization (TVR), while progress and innovations in stent materials have in the meantime facilitated the design of newer platforms with more conformability and thinner struts, producing lesser injury and improving integration into the vessel wall. Recent advances in biodegradable metal and polymer materials now also allow for the design of fully biodegradable platforms, which are aimed at scaffolding the vessel only temporarily to prevent recoil and constrictive remodeling of the vessel during the initial period required, and are then progressively resorbed thereby avoiding the drawback of leaving an unnecessary implant permanently in the vessel. The aim of this article is to review recent evolution in stent material and stent strut design while understanding their impact on PCI outcomes. The article describes the different metallic alloys and biodegradable material properties and how these have impacted the evolution of stent strut thickness and ultimately outcomes in patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. The biodurability of covering materials for metallic stents in a bile flow phantom.

    PubMed

    Bang, Byoung Wook; Jeong, Seok; Lee, Don Haeng; Lee, Jung Il; Lee, Se Chul; Kang, Sung-Gwon

    2012-04-01

    Covered biliary metal stents have been introduced for the purpose of overcoming tumor ingrowth and treatment of benign biliary stricture. The aim of this study was to evaluate the biodurability of three commercially available biliary metal stent covering materials [e-PTFE (expanded polytetrafluoroethylene), silicone, and polyurethane] in a bile flow phantom. By operation of a peristaltic pump, human bile was circulated continuously in an experimental perfusion system containing covered metal stents. Each stent was removed, respectively, 1, 2, 4, and 6 months after bile exposure. We performed a gross inspection of the covered stents. The covering membrane was detached from the stent and observed by scanning electron microscopy (SEM). Finally, we measured tensile and tear strength of the membranes. Bile-staining of the membrane showed gradual progression after bile exposure; however, progress was the fastest in e-PTFE. SEM examination showed that the polyurethane surface was smooth, and the silicone surface was relatively smooth. However, e-PTFE had a rough and uneven surface. After bile exposure, there were no significant changes in polyurethane and silicone; however, biofilms and microcracks were observed in e-PTFE. In contrast to a gradual decrease of tensile/tear strength of polyurethane and silicone, those of e-PTFE showed a rapid reduction despite of the strongest baseline tensile and tear strength. e-PTFE tended to form biofilms more frequently than polyurethane and silicone during bile exposure. e-PTFE seemed to be less durable than silicone and polyurethane, however, as clinically applicable material because of strong absolute tensile/tear strengths.

  17. Metallic stents for tracheobronchial pathology treatment.

    PubMed

    Serrano, Carolina; Laborda, Alicia; Lozano, Juan M; Caballero, Hugo; Sebastián, Antonio; Lopera, Jorge; de Gregorio, Miguel Ángel

    2013-12-01

    To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 ± 1.2 months in patients with malignant lesions and 76.2 ± 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results.

  18. Metallic Stents for Tracheobronchial Pathology Treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Serrano, Carolina, E-mail: carolina.serrano@unizar.es; Laborda, Alicia, E-mail: alaborda@unizar.es; Lozano, Juan M., E-mail: juamauloz@gmail.com

    2013-12-15

    Purpose: To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. Patients and Methods: One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniquesmore » at 48 h and at 1-, 3-, 6-, and 12-month intervals. Results: The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 {+-} 1.2 months in patients with malignant lesions and 76.2 {+-} 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Conclusion: Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results.« less

  19. Clinical outcome of endoscopic covered metal stenting for resolution of benign biliary stricture: Systematic review and meta-analysis.

    PubMed

    Zheng, Xiao; Wu, Jun; Sun, Bo; Wu, Ye-Chen; Bo, Zhi-Yuan; Wan, Wei; Gao, Dao-Jian; Hu, Bing

    2017-03-01

    Management of benign biliary stricture is challenging. Endoscopic therapy has evolved as the first-line treatment for various benign biliary strictures. However, covered self-expandable metal stents (CSEMS) have not been approved by the United States Food and Drug Administration for the treatment of benign biliary stricture. With this goal, we conducted the present systemic review and meta-analysis to evaluate the efficacy and safety of endoscopic stenting with CSEMS in the treatment of benign biliary stricture. Systematic review and meta-analysis by searching PubMed, MEDLINE and Embase databases. In total, 37 studies (1677 patients) fulfilled the inclusion criteria. Pooled stricture resolutions were achieved in 83% of cases. Median stent dwelling time was 4.4 months, with median endoscopic retrograde cholangiopancreatography sessions of 2.0. Stricture recurrence at 4-year follow up was 11% (95% CI, 8-14%). Pooled complication rate was 23% (95% CI, 20-26%). Placement of CSEMS is effective in the treatment of benign biliary stricture with relatively short stenting duration and low long-term stricture recurrence rate. However, more prospectively randomized studies are required to confirm the results. © 2016 Japan Gastroenterological Endoscopy Society.

  20. Composite self-expanding bioresorbable prototype stents with reinforced compression performance for congenital heart disease application: Computational and experimental investigation.

    PubMed

    Zhao, Fan; Xue, Wen; Wang, Fujun; Liu, Laijun; Shi, Haoqin; Wang, Lu

    2018-08-01

    Stents are vital devices to treat vascular stenosis in pediatric patients with congenital heart disease. Bioresorbable stents (BRSs) have been applied to reduce challenging complications caused by permanent metal stents. However, it remains almost a total lack of BRSs with satisfactory compression performance specifically for children with congenital heart disease, leading to importantly suboptimal effects. In this work, composite bioresorbable prototype stents with superior compression resistance were designed by braiding and annealing technology, incorporating poly (p-dioxanone) (PPDO) monofilaments and polycaprolactone (PCL) multifilament. Stent prototype compression properties were investigated. The results revealed that novel composite prototype stents showed superior compression force compared to the control ones, as well as recovery ability. Furthermore, deformation mechanisms were analyzed by computational simulation, which revealed bonded interlacing points among yarns play an important role. This research presents important clinical implications in bioresorbable stent manufacture and provides further study with an innovative stent design. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Endoscopic stenting for benign upper gastrointestinal strictures and leaks.

    PubMed

    Sharaiha, Reem Z; Kim, Katherine J; Singh, Vikesh K; Lennon, Anne Marie; Amateau, Stuart K; Shin, Eun Ji; Canto, Marcia Irene; Kalloo, Anthony N; Khashab, Mouen A

    2014-01-01

    Self-expandable metal stents (SEMS) and self-expandable plastic stents (SEPS) maybe used for the treatment of benign upper gastrointestinal (GI) leaks and strictures. This study reviewed our experience with stent insertions in patients with benign upper GI conditions. Patients who underwent stent placement for benign upper GI strictures and leaks between March 2007 and April 2011 at a tertiary referral academic center were studied using an endoscopic database and electronic patient records. The technical success, complications, and clinical improvement after stent removal were compared according to type of stent. The outcomes measured were clinical response, adverse events, and predictors of stent migration. Thirty-eight patients (50 % male, mean age = 54 years, range = 12-82) underwent 121 endoscopic procedures. Twenty patients had stents placed for strictures, and 18 had stents placed for leaks. Stent placement was technically successful in all patients. The average duration of stent placement was 54 days (range = 18-118). Clinical improvement immediately after stent placement was seen in 29 of the 38 patients (76.3 %). Immediate post-procedure adverse events occurred in 8 patients. Late adverse events were seen in 18 patients. Evidence of stent migration occurred in 16 patients and was seen in 42 of the 118 successfully placed stents (35.5 %). Migration was more frequent with fully covered SEMS (p = 0.002). After stent removal, 27 patients were evaluable for long-term success (median follow-up time of 283 days, IQR 38-762). Resolution of strictures or leaks was seen in 11 patients (40.7 %). Predictors for long-term success included increasing age and if the stent did not cross the GE junction. Placement of SEPS and SEMS for benign refractory strictures and fistulas has modest long-term clinical efficacy and is limited by a significant migration rate. Stent migration is common and frequent with fully covered SEMS compared to other types of stents, regardless of

  2. PEACE I all-comers registry: patency evaluation after implantation of the 4-French Pulsar-18 self-expanding nitinol stent in femoropopliteal lesions.

    PubMed

    Lichtenberg, Michael; Kolks, Oliver; Hailer, Birgit; Stahlhoff, Wilhelm-Friedrich; Tiefenbacher, Christiane; Nolte-Ernsting, Claus; Arjumand, Jawed; Wittenberg, Guenther

    2014-06-01

    To evaluate the 1-year patency of the 4-F Pulsar-18 self-expanding nitinol stent for treatment of femoropopliteal occlusive disease in a national, prospective, multicenter, all-comers registry. Between January and June 2012, the German PEACE I all-comers prospective registry enrolled 148 patients with symptomatic femoropopliteal lesions (Rutherford category 2-5) undergoing recanalization and implantation of the Pulsar-18 SE nitinol stent at 6 clinical centers. Thirty patients did not have the 12-month follow-up visit (18 declined reevaluation, 5 withdrew consent, and 7 died), leaving 118 patients (64 men; mean 71.9±9.6 age years) for the 1-year evaluation. The average lesion length was 111.5±71.4 mm, and 38 of the 118 lesions were classified as TASC II D. More than half the lesions (67, 56.7%) were chronic total occlusions (CTO). The popliteal segment was involved in 22 (18.7%) lesions. The mean stented length was 122.7±64.5 mm. Routine follow-up included duplex ultrasound at 6 and 12 months. Outcome measures were primary patency and no clinically driven target lesion revascularization (TLR) within 12 months. The overall primary patency rates after 6 and 12 months were 87.4% and 79.5%, respectively; in the popliteal segments, the rate was 71.4% after 12 months. The overall freedom from TLR was 93.2% after 6 months and 81% after 12 months. Ankle-brachial index, pain-free walking distance, and Rutherford category all improved significantly (p<0.0001) after 6 and 12 months. The primary patency rates in patients with diabetes (p=1.0) and those with renal insufficiency (p=0.8) were not significantly lower compared to the overall rate. There was no significant difference (p=0.67) in restenosis rate for recanalization of CTOs compared to non-CTO lesions. In this all-comers registry, the use of the Pulsar-18 self-expanding nitinol stent in femoropopliteal lesions averaging 111.5 mm long showed promising primary patency and freedom from TLR after 6 and 12 months

  3. Biodegradable Metals for Cardiovascular Stent Application: Interests and New Opportunities

    PubMed Central

    Moravej, Maryam; Mantovani, Diego

    2011-01-01

    During the last decade, biodegradable metallic stents have been developed and investigated as alternatives for the currently-used permanent cardiovascular stents. Degradable metallic materials could potentially replace corrosion-resistant metals currently used for stent application as it has been shown that the role of stenting is temporary and limited to a period of 6–12 months after implantation during which arterial remodeling and healing occur. Although corrosion is generally considered as a failure in metallurgy, the corrodibility of certain metals can be an advantage for their application as degradable implants. The candidate materials for such application should have mechanical properties ideally close to those of 316L stainless steel which is the gold standard material for stent application in order to provide mechanical support to diseased arteries. Non-toxicity of the metal itself and its degradation products is another requirement as the material is absorbed by blood and cells. Based on the mentioned requirements, iron-based and magnesium-based alloys have been the investigated candidates for biodegradable stents. This article reviews the recent developments in the design and evaluation of metallic materials for biodegradable stents. It also introduces the new metallurgical processes which could be applied for the production of metallic biodegradable stents and their effect on the properties of the produced metals. PMID:21845076

  4. Successful management of multiple esophagorespiratory fistulas using two types of stent: report of a case.

    PubMed

    Hamai, Yoichi; Hihara, Jun; Emi, Manabu; Okita, Riki; Shimizu, Katsuhiko; Okada, Morihito

    2011-04-01

    We herein describe a 41-year-old man with esophageal cancer who developed three esophagorespiratory fistulas (ERFs) that were successfully treated using one esophageal and three airway stents. A self-expandable metallic stent (SEMS) was initially inserted into the esophagus to close an ERF in the right bronchus. However, two new ERFs developed in the trachea and the left main bronchus 3 months later because of pressure necrosis and penetration of the esophageal SEMS. These secondary ERFs were subsequently closed using two silicone stents, together with one SEMS in the airway. This experience suggests that appropriate stenting can control multiple and large ERFs.

  5. The BioStent: novel concept for a viable stent structure.

    PubMed

    Weinandy, Stefan; Rongen, Lisanne; Schreiber, Fabian; Cornelissen, Christian; Flanagan, Thomas Cormac; Mahnken, Andreas; Gries, Thomas; Schmitz-Rode, Thomas; Jockenhoevel, Stefan

    2012-09-01

    Percutaneous stenting of occluded peripheral vessels is a well-established technique in clinical practice. Unfortunately, the patency rates of small-caliber vessels after stenting remain unsatisfactory. The aim of the BioStent concept is to overcome in-stent restenosis by excluding the diseased vessel segment entirely from the blood stream, in addition to providing an intact endothelial cell layer. The concept combines the principles of vascular tissue engineering with a self-expanding stent: casting of the stent within a cellularized fibrin gel structure, followed by bioreactor conditioning, allows complete integration of the stent within engineered tissue. Small-caliber BioStents (Ø=6 mm; n=4) were produced by casting a nitinol stent within a thin fibrin/vascular smooth muscle cell (vSMC) mixture, followed by luminal endothelial cell seeding, and conditioning of the BioStent within a bioreactor system. The potential remodeling of the fibrin component into tissue was analyzed using routine histological methods. Scanning electron microscopy was used to assess the luminal endothelial cell coverage following the conditioning phase and crimping of the stent. The BioStent was shown to be noncytotoxic, with no significant effect on cell proliferation. Gross and microscopic analysis revealed complete integration of the nitinol component within a viable tissue structure. Hematoxylin and eosin staining revealed a homogenous distribution of vSMCs throughout the thickness of the BioStent, while a smooth, confluent luminal endothelial cell lining was evident and not significantly affected by the crimping/release process. The BioStent concept is a platform technology offering a novel opportunity to generate a viable, self-expanding stent structure with a functional endothelial cell lining. This platform technology can be transferred to different applications depending on the luminal cell lining required.

  6. Acute Duodenal Obstruction After Percutaneous Placement of Metallic Biliary Stents: Peroral Treatment with Enteral Stents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lopera, Jorge E.; Alvarez, Oscar A.; Perdigao, Joseph

    2003-09-15

    Three patients with malignant biliary obstruction were treated with placement of metallic biliary stents. Two patients had known partial duodenal stenosis but had no symptoms of gastrointestinal obstruction. The patients developed symptomatic duodenal obstruction early after biliary metallic stent placement. The symptomatic duodenal obstructions were successfully treated with peroral placement of duodenal stents, which obviated the need for surgical intervention.

  7. High single-session success rate of endoscopic bilateral stent-in-stent placement with modified large cell Niti-S stents for malignant hilar biliary obstruction.

    PubMed

    Kogure, Hirofumi; Isayama, Hiroyuki; Nakai, Yousuke; Tsujino, Takeshi; Matsubara, Saburo; Yashima, Yoko; Ito, Yukiko; Hamada, Tsuyoshi; Takahara, Naminatsu; Miyabayashi, Koji; Mizuno, Suguru; Mohri, Dai; Kawakubo, Kazumichi; Sasaki, Takashi; Yamamoto, Natsuyo; Hirano, Kenji; Sasahira, Naoki; Tada, Minoru; Koike, Kazuhiko

    2014-01-01

    Endoscopic bilateral self-expandable metallic stent (SEMS) placement in a stent-in-stent method for malignant hilar biliary obstruction is technically challenging. Technical difficulties in the initial placement and reinterventions for stent occlusion are disadvantages inherent to this stent-in-stent method. We previously reported the feasibility of Niti-S large cell D-type biliary stents (LCD). This multicenter prospective consecutive study evaluated the efficacy of bilateral SEMS placement using modified LCD with large and uniform cells, a slimmer delivery system and high radial force. From July 2010 to June 2011, 26 consecutive patients with unresectable malignant hilar biliary obstruction underwent endoscopic bilateral placement of modified LCD in a stent-in-stent method at three tertiary hospitals. Ten patients had gallbladder cancer, eight had cholangiocarcinoma, four had lymph node metastasis, two had intrahepatic cholangiocarcinoma, and two had liver metastasis. Single-session and final technical success rate was 96% and 100%, respectively. Functional success rate was 89%. Stent occlusion occurred in 11 patients (42%) because of sludge (n = 7) or tumor ingrowth (n = 4). Endoscopic bilateral reintervention was technically easy and successful: six patients had stent clearance by balloon sweeping and five had plastic stent placement. According to Kaplan-Meier analysis, median survival and stent patency were 220 days and 157 days, respectively. Modified LCD achieved a high technical success rate both in the initial stent-in-stent placement and in bilateral reinterventions in patients with malignant hilar biliary obstruction. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  8. Endoscopic stent suture fixation for prevention of esophageal stent migration during prolonged dilatation for achalasia treatment.

    PubMed

    Rieder, E; Asari, R; Paireder, M; Lenglinger, J; Schoppmann, S F

    2017-04-01

    The aim of this study is to compare endoscopic stent suture fixation with endoscopic clip attachment or the use of partially covered stents (PCS) regarding their capability to prevent stent migration during prolonged dilatation in achalasia. Large-diameter self-expanding metal stents (30 mm × 80 mm) were placed across the gastroesophageal junction in 11 patients with achalasia. Stent removal was scheduled after 4 to 7 days. To prevent stent dislocation, endoscopic clip attachment, endoscopic stent suture fixation, or PCS were used. The Eckardt score was evaluated before and 6 months after prolonged dilatation. After endoscopic stent suture fixation, no (0/4) sutured stent migrated. When endoscopic clips were used, 80% (4/5) clipped stents migrated (p = 0.02). Of two PCS (n = 2), one migrated and one became embedded leading to difficult stent removal. Technical adverse events were not seen in endoscopic stent suture fixation but were significantly correlated with the use of clips or PCS (r = 0.828, p = 0.02). Overall, 72% of patients were in remission regarding their achalasia symptoms 6 months after prolonged dilatation. Endoscopic suture fixation of esophageal stents but not clip attachment appears to be the best method of preventing early migration of esophageal stents placed at difficult locations such as at the naive gastroesophageal junction. © The Authors 2017. Published by Oxford University Press on behalf of International Society for Diseases of the Esophagus. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Metallic ureteral stents in malignant ureteral obstruction: clinical factors predicting stent failure.

    PubMed

    Chow, Po-Ming; Hsu, Jui-Shan; Huang, Chao-Yuan; Wang, Shuo-Meng; Lee, Yuan-Ju; Huang, Kuo-How; Yu, Hong-Jheng; Pu, Yeong-Shiau; Liang, Po-Chin

    2014-06-01

    To provide clinical outcomes of the Resonance metallic ureteral stent in patients with malignant ureteral obstruction, as well as clinical factors predicting stent failure. Cancer patients who have received Resonance stents from July 2009 to March 2012 for ureteral obstruction were included for chart review. Stent failure was detected by clinical symptoms, image studies, and renal function tests. Survival analysis for stent duration was used to estimate patency rate and factors predicting stent failure. A total of 117 stents were inserted successfully into 94 ureteral units in 79 patients. There were no major complications. These stents underwent survival analysis and proportional hazard regression. The median duration for the stents was 5.77 months. In multivariate analysis, age (P=0.043), preoperative serum creatinine level (P=0.0174), and cancer type (P=0.0494) were significant factors associated with stent failure. Cancer treatment before and after stent insertion had no effect on stent duration. Resonance stents are effective and safe in relieving malignant ureteral obstructions. Old age and high serum creatinine level are predictors for stent failure. Stents in patients with lower gastrointestinal cancers have longer functional duration.

  10. Self-expanding/shrinking structures by 4D printing

    NASA Astrophysics Data System (ADS)

    Bodaghi, M.; Damanpack, A. R.; Liao, W. H.

    2016-10-01

    The aim of this paper is to create adaptive structures capable of self-expanding and self-shrinking by means of four-dimensional printing technology. An actuator unit is designed and fabricated directly by printing fibers of shape memory polymers (SMPs) in flexible beams with different arrangements. Experiments are conducted to determine thermo-mechanical material properties of the fabricated part revealing that the printing process introduced a strong anisotropy into the printed parts. The feasibility of the actuator unit with self-expanding and self-shrinking features is demonstrated experimentally. A phenomenological constitutive model together with analytical closed-form solutions are developed to replicate thermo-mechanical behaviors of SMPs. Governing equations of equilibrium are developed for printed structures based on the non-linear Green-Lagrange strain tensor and solved implementing a finite element method along with an iterative incremental Newton-Raphson scheme. The material-structural model is then applied to digitally design and print SMP adaptive lattices in planar and tubular shapes comprising a periodic arrangement of SMP actuator units that expand and then recover their original shape automatically. Numerical and experimental results reveal that the proposed planar lattice as meta-materials can be employed for plane actuators with self-expanding/shrinking features or as structural switches providing two different dynamic characteristics. It is also shown that the proposed tubular lattice with a self-expanding/shrinking mechanism can serve as tubular stents and grippers for bio-medical or piping applications.

  11. Flexible endoscopy for pediatric tracheobronchial metallic stent placement, maintenance and long-term outcomes

    PubMed Central

    2018-01-01

    Objectives To assess the placement, surveillance management and long-term outcomes of the tracheobronchial (TB) balloon expandable metallic stent (BEMS) managed by therapeutic flexible endoscopy (TFE). Methods This is a retrospective review and analysis of all computerized medical records and related flexible endoscopy videos of pediatric patients who received TB BEMS during 20 years period, from January 1997 to December 2016. TFE techniques with forceps debridement, balloon dilatation and laser ablation were used to implant stents, perform regular surveillance, maintain their functions, and expand the diameters of BEMS. Short-length (30cm-36cm) endoscopes of OD 3.2mm to 5.0mm coupled with the noninvasive ventilation, without ventilation bag, mask or airway tube, supported the whole procedures. Results 146 BEMS were implanted in 87 consecutive children, including 84 tracheal, 15 carinal and 47 bronchial stents. At the time of placement, the mean age was 35.6 ± 54.6 month-old (range 0.3–228) and the mean body weight was 13.9 ± 10.6 kg (range 2.2–60). Surveillance period was 9.4 ± 6.7 years (range, 0.3–18.0). Satisfactory clinical improvements were noted immediately in all but two patients. Seventy-two (82.8%) patients were still alive with stable respiratory status, except two patients necessitating TFE management every two months. Fifty-one stents, including 35 tracheal and 16 bronchial ones, were successfully retrieved mainly with rigid endoscopy. Implanted stents could be significantly (< .001) further expanded for growing TB lumens. The final stent diameters were positively correlated to the implanted duration. Altogether, 33 stents expired (15 patients), 51 were retrieved (40 patients), and 62 remained and functioning well (38 patients), with their mean duration of 7.4 ± 9.5, 34.9 ± 36.3 and 82.3 ± 62.5 months, respectively. Conclusion In pediatric patients, TFE with short-length scopes coupled with this NIV support has provided a safe, feasible and

  12. Comparison of the influence of plastic and fully covered metal biliary stents on the accuracy of EUS-FNA for the diagnosis of pancreatic cancer.

    PubMed

    Siddiqui, Ali A; Fein, Michael; Kowalski, Thomas E; Loren, David E; Eloubeidi, Mohamad A

    2012-09-01

    Prior studies have reported that the presence of prior biliary stent may interfere with EUS visualization of pancreatic tumors. We aimed to compare the influence of the biliary plastic and fully covered self-expanding metal stents (CSEMS) on the accuracy of EUS-FNA cytology in patients with solid pancreatic masses. We conducted a retrospective study evaluating 677 patients with solid pancreatic head/uncinate lesions and a previous biliary stent in whom EUS-FNA was performed. The patients were stratified into two groups: (1) those with a plastic stents and (2) those with CSEMS. Performance characteristics of EUS-FNA including the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were compared between the two groups. The frequency of obtaining an adequate cytology by EUS-FNA was similar in both the CSEMS group and the plastic stent group (97 vs. 97.1 % respectively; p = 1.0). The sensitivity, specificity, and accuracy of EUS-FNA was not significantly different between patients with CSEMS and plastic stents (96.8, 100, 100 % and 97.3, 98, 99.8 %, respectively). The negative predictive value for EUS-FNA was lower in the CSEMS group compared to the plastic stent group (66.6 vs. 78.1 % respectively; p = 0.42). There was one false-positive cytology in the plastic stent group compared to none in the CSEMS group. In a retrospective cohort trial, EUS-FNA was found to be highly accurate and safe in diagnosing patients with suspected pancreatic cancer, even in the presence of a plastic or metallic biliary stent. The presence of a stent did not contribute to a higher false-positive cytology rate.

  13. TOKYO criteria 2014 for transpapillary biliary stenting.

    PubMed

    Isayama, Hiroyuki; Hamada, Tsuyoshi; Yasuda, Ichiro; Itoi, Takao; Ryozawa, Shomei; Nakai, Yousuke; Kogure, Hirofumi; Koike, Kazuhiko

    2015-01-01

    It is difficult to carry out meta-analyses or to compare the results of different studies of biliary stents because there is no uniform evaluation method. Therefore, a standardized reporting system is required. We propose a new standardized system for reporting on biliary stents, the 'TOKYO criteria 2014', based on a consensus among Japanese pancreatobiliary endoscopists. Instead of stent occlusion, we use recurrent biliary obstruction, which includes occlusion and migration. The time to recurrent biliary obstruction was estimated using Kaplan-Meier analysis with the log-rank test. We can evaluate both plastic and self-expandable metallic stents (uncovered and covered). We also propose specification of the cause of recurrent biliary obstruction, identification of complications other than recurrent biliary obstruction, indication of severity, measures of technical and clinical success, and a standard for clinical care. Most importantly, the TOKYO criteria 2014 allow comparison of biliary stent quality across studies. Because blocked stents can be drained not only using transpapillary techniques but also by an endoscopic ultrasonography-guided transmural procedure, we should devise an evaluation method that includes transmural stenting in the near future. © 2014 The Authors. Digestive Endoscopy © 2014 Japan Gastroenterological Endoscopy Society.

  14. Metallic Full-Length Ureteral Stents: Does Urinary Tract Infection Cause Obstruction?

    PubMed Central

    Brown, James A.; Powell, Christopher L.; Carlson, Kristopher R.

    2010-01-01

    Metallic ureteral stents promise to offer superior upper urinary tract drainage with extended exchange intervals and freedom from extrinsic compression in patients with advanced malignancy or other significant obstructing retroperitoneal or pelvic processes. Existing literature indicates a variable experience with these relatively new devices, with some investigators reporting excellent results and long problem-free intervals, and others reporting less enthusiastic outcomes. We report a retrospective review of a series of five sequential patients undergoing placement of Resonance® (Cook Medical, Bloomington, IN) metallic ureteral stents for extrinsic ureteral compression refractory to placement of traditional (polymer) ureteral stents. Of five patients reviewed, three (60%) required additional operative intervention for stent migration or malposition. Four patients (80%) died of their primary malignancy <12 months after metallic stent placement. Four (80%) of five patients had obstruction of their stents demonstrated with nuclear renography and/or other imaging, and three (60%) required removal and alternative means of urinary tract drainage within 4 months of placement due to obstruction, intractable pain, or migration. Four patients (80%) had urinary tract infections (UTIs) within 4 months of stent placement. No obstruction was seen due to extrinsic ureteral compression after stent placement. Metallic ureteral stents may have utility for patients with pathological processes causing extrinsic ureteral compression refractory to the use of traditional polymer ureteral stents. However, metallic ureteral stents are not immune to obstruction, migration, and associated discomfort. Stent obstruction appears to be increased in patients with postoperative UTI. PMID:20730376

  15. Metallic full-length ureteral stents: does urinary tract infection cause obstruction?

    PubMed

    Brown, James A; Powell, Christopher L; Carlson, Kristopher R

    2010-08-17

    Metallic ureteral stents promise to offer superior upper urinary tract drainage with extended exchange intervals and freedom from extrinsic compression in patients with advanced malignancy or other significant obstructing retroperitoneal or pelvic processes. Existing literature indicates a variable experience with these relatively new devices, with some investigators reporting excellent results and long problem-free intervals, and others reporting less enthusiastic outcomes. We report a retrospective review of a series of five sequential patients undergoing placement of Resonance (Cook Medical, Bloomington, IN) metallic ureteral stents for extrinsic ureteral compression refractory to placement of traditional (polymer) ureteral stents. Of five patients reviewed, three (60%) required additional operative intervention for stent migration or malposition. Four patients (80%) died of their primary malignancy <12 months after metallic stent placement. Four (80%) of five patients had obstruction of their stents demonstrated with nuclear renography and/or other imaging, and three (60%) required removal and alternative means of urinary tract drainage within 4 months of placement due to obstruction, intractable pain, or migration. Four patients (80%) had urinary tract infections (UTIs) within 4 months of stent placement. No obstruction was seen due to extrinsic ureteral compression after stent placement. Metallic ureteral stents may have utility for patients with pathological processes causing extrinsic ureteral compression refractory to the use of traditional polymer ureteral stents. However, metallic ureteral stents are not immune to obstruction, migration, and associated discomfort. Stent obstruction appears to be increased in patients with postoperative UTI.

  16. The STENTYS self-apposing stent technology in coronary artery disease: literature review and future directions.

    PubMed

    Lu, Huangling; de Winter, Robbert J; Koch, Karel T

    2018-06-21

    Coronary stent designs have been through extensive developments in the past few decades. Since the first introduction of the self-apposing STENTYS stent, several theoretical advantages of its nitinol platform have been clinically evaluated. This paper reviews the current status, ongoing work and future directions of this device. Areas covered: The OPEN (STENTYS Coronary Bifurcation Stent System fOr the PErcutaNeous treatment of de novo lesions in native bifurcated coronary arteries) trials revealed high technical success rates of the STENTYS performance in bifurcation lesions. The APPOSITION (Assessment of the Safety and Performance of the STENTYS self-expanding Coronary Stent in Acute Myocardial Infarction) trials demonstrated the safety and feasibility of the device in patients with acute myocardial infarction. Optical coherence tomography showed better short-term strut apposition in patients treated with the STENTYS stent in APPOSITION IV. The clinical outcomes of the device in saphenous vein graft lesions and left main coronary artery disease are favourable. Expert Commentary: Despite numerous theoretical advantages of the nitinol platform, superiority of the STENTYS self-apposing stent over currently available DES has not yet been proven. However, the ongoing registries evaluating the performance of the STENTYS Xposition will provide more insights in its clinical performance.

  17. Silane surface modification for improved bioadhesion of esophageal stents

    NASA Astrophysics Data System (ADS)

    Karakoy, Mert; Gultepe, Evin; Pandey, Shivendra; Khashab, Mouen A.; Gracias, David H.

    2014-08-01

    Stent migration occurs in 10-40% of patients who undergo placement of esophageal stents, with higher migration rates seen in those treated for benign esophageal disorders. This remains a major drawback of esophageal stent therapy. In this paper, we propose a new surface modification method to increase the adhesion between self-expandable metallic stents (SEMS) and tissue while preserving their removability. Taking advantage of the well-known affinity between epoxide and amine terminated silane coupling agents with amine and carboxyl groups that are abundant in proteins and related molecules in the human body; we modified the surfaces of silicone coated esophageal SEMS with these adhesive self-assembled monolayers (SAMs). We utilized vapor phase silanization to modify the surfaces of different substrates including PDMS strips and SEMS, and measured the force required to slide these substrates on a tissue piece. Our results suggest that surface modification of esophageal SEMS via covalent attachment of protein-binding coupling agents improves adhesion to tissue and could offer a solution to reduce SEMS migration while preserving their removability.

  18. Silane surface modification for improved bioadhesion of esophageal stents

    PubMed Central

    Karakoy, Mert; Gultepe, Evin; Pandey, Shivendra; Khashab, Mouen A.; Gracias, David H.

    2014-01-01

    Stent migration occurs in 10-40% of patients who undergo placement of esophageal stents, with higher migration rates seen in those treated for benign esophageal disorders. This remains a major drawback of esophageal stent therapy. In this paper, we propose a new surface modification method to increase the adhesion between self-expandable metallic stents (SEMS) and tissue while preserving their removability. Taking advantage of the well-known affinity between epoxide and amine terminated silane coupling agents with amine and carboxyl groups that are abundant in proteins and related molecules in the human body; we modified the surfaces of silicone coated esophageal SEMS with these adhesive self-assembled monolayers (SAMs). We utilized vapor phase silanization to modify the surfaces of different substrates including PDMS strips and SEMS, and measured the force required to slide these substrates on a tissue piece. Our results suggest that surface modification of esophageal SEMS via covalent attachment of protein-binding coupling agents improves adhesion to tissue and could offer a solution to reduce SEMS migration while preserving their removability. PMID:25663731

  19. Treatment of Post-Stent Gastroesophageal Reflux by Anti-Reflux Z-Stent

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Davies, Roger Philip; Kew, Jacqueline; Byrne, Peter D.

    2000-11-15

    Severe symptoms of heartburn and retrosternal pain consistent with gastro-esophageal reflux (GER) developed in a patient following placement of a conventional self-expanding 16-24-mm-diameter x 12-cm-long esophageal stent across the gastroesophageal junction to treat an obstructing esophageal carcinoma. A second 18-mm-diameter x 10-cm-long esophageal stent with anti-reflux valve was deployed coaxially and reduced symptomatic GER immediately. Improvement was sustained at 4-month follow-up. An anti-reflux stent can be successfully used to treat significant symptomatic GER after conventional stenting.

  20. Self‐expanding stent effects on radiation dosimetry in esophageal cancer

    PubMed Central

    Francis, Samual R.; Wang, Brian; Williams, Greg V.; Cox, Kristen; Adler, Douglas G.; Shrieve, Dennis C.; Salter, Bill J.

    2013-01-01

    It is the purpose of this study to evaluate how self‐expanding stents (SESs) affect esophageal cancer radiation planning target volumes (PTVs) and dose delivered to surrounding organs at risk (OARs). Ten patients were evaluated, for whom a SES was placed before radiation. A computed tomography (CT) scan obtained before stent placement was fused to the post‐stent CT simulation scan. Three methods were used to represent pre‐stent PTVs: 1) image fusion (IF), 2) volume approximation (VA), and 3) diameter approximation (DA). PTVs and OARs were contoured per RTOG 1010 protocol using Eclipse Treatment Planning software. Post‐stent dosimetry for each patient was compared to approximated pre‐stent dosimetry. For each of the three pre‐stent approximations (IF, VA, and DA), the mean lung and liver doses and the estimated percentages of lung volumes receiving 5 Gy, 10 Gy, 20 Gy, and 30 Gy, and heart volumes receiving 40 Gy were significantly lower (p‐values <0.02) than those estimated in the post‐stent treatment plans. The lung V5, lung V10, and heart V40 constraints were achieved more often using our pre‐stent approximations. Esophageal SES placement increases the dose delivered to the lungs, heart, and liver. This may have clinical importance, especially when the dose‐volume constraints are near the recommended thresholds, as was the case for lung V5, lung V10, and heart V40. While stents have established benefits for treating patients with significant dysphagia, physicians considering stent placement and radiation therapy must realize the effects stents can have on the dosimetry. PACS number: 87.55.dk PMID:23835387

  1. Stent Angioplasty of Closed Mesocaval Shunt in a Patient with Budd-Chiari Syndrome

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sancak, Tanzer; Karagulle, Ayse Tuba; Bilgic, Sadik

    Budd-Chiari syndrome (BCS) is an uncommon disorder caused by hepatic venous outflow obstruction. It is characterized by ascites, hepatomegaly and abdominal pain. Percutaneous intervention shave recently been used for the treatment of BCS. We present a case of BCS with a closed mesocaval shunt which was reopened with a self-expandable metallic stent.

  2. Evidence-Based Recommendations on Colorectal Stenting: A Report from the Stent Study Group of the Korean Society of Gastrointestinal Endoscopy

    PubMed Central

    Lee, Kwang Jae; Kim, Sang Woo; Kim, Tae Il; Lee, Jong-Hoon; Lee, Bo-In; Keum, Bora; Cheung, Dae Young

    2013-01-01

    Recently, placement of self-expandable metallic stents has been used for the treatment of colorectal obstruction. As domestic awareness of colorectal cancer has increased, the number of colorectal stenting procedures performed has also increased. We aimed to provide evidence-based recommendations for colorectal stenting to aid gastroenterologists in making informed decisions regarding the management of patients who present with colorectal obstruction. The working group consisted of eight gastroenterologists who actively practice and conduct research in the field of colorectal stenting and are the members of the Stent Study Group of the Korean Society of Gastrointestinal Endoscopy. A literature search was conducted using the PubMed, Embase, KoreaMed, and the Cochrane Library databases to identify relevant articles published between January 2001 and June 2012. Based on the modified Delphi process, 10 recommendation statements regarding indications, usefulness, methodology and complications of colorectal stenting, and alternative treatments for malignant colorectal obstruction were determined. The contents will be widely distributed, and periodically revised to reflect the latest knowledge. These evidence-based recommendations for colorectal stenting will provide gastroenterologists and patients with appropriate and balanced information, and will improve the quality of care. PMID:23964332

  3. Endoscopic Drainage of >50% of Liver in Malignant Hilar Biliary Obstruction Using Metallic or Fenestrated Plastic Stents

    PubMed Central

    Kerdsirichairat, Tossapol; Arain, Mustafa A; Attam, Rajeev; Glessing, Brooke; Bakman, Yan; Amateau, Stuart K; Freeman, Martin L

    2017-01-01

    Objectives: Endoscopic drainage of complex hilar tumors has generally resulted in poor outcomes. Drainage of >50% of liver volume has been proposed as optimal, but not evaluated using long multifenestrated plastic stents (MFPS) or self-expanding metal stents (SEMS). We evaluated outcomes of endoscopic drainage of malignant hilar strictures using optimal strategy and stents, and determined factors associated with stent patency, survival, and complications. Methods: Cross-sectional study was conducted at an academic center over 5 years. MFPS (10 French or 8.5 French) or open-cell SEMS were used for palliation of unresectable malignant hilar strictures, with imaging-targeted drainage of as many sectors as needed to drain >50% of viable liver volume. Risk factors were evaluated using regression analysis. The cumulative risk was assessed using Kaplan–Meier analysis. Results: 77 patients with malignant hilar biliary strictures (median Bismuth IV) underwent targeted stenting (41 MFPS and 36 SEMS). Comparing MFPS vs. SEMS, technical success (95.1 vs. 97.2%, P=0.64), clinical success (75.6 vs. 83.3%, P=0.40), frequency of multiple stents (23/41 vs. 25/36, P=0.19), survival and adverse events were similar, but stent patency was significantly shorter (P<0.0001). Factors associated with survival were Karnofsky score and serum bilirubin level at presentation. Outcomes were independent of Bismuth class with acceptable results in Bismuth III and IV. Conclusions: Endoscopic biliary drainage with MFPS or open-cell SEMS targeting >50% of viable liver resulted in effective palliation in patients with complex malignant hilar biliary strictures. Patency was shorter in the MFPS group, but similar survival and complications were found when comparing MFPS and SEMS group. PMID:28858292

  4. Endoscopic Drainage of >50% of Liver in Malignant Hilar Biliary Obstruction Using Metallic or Fenestrated Plastic Stents.

    PubMed

    Kerdsirichairat, Tossapol; Arain, Mustafa A; Attam, Rajeev; Glessing, Brooke; Bakman, Yan; Amateau, Stuart K; Freeman, Martin L

    2017-08-31

    Endoscopic drainage of complex hilar tumors has generally resulted in poor outcomes. Drainage of >50% of liver volume has been proposed as optimal, but not evaluated using long multifenestrated plastic stents (MFPS) or self-expanding metal stents (SEMS). We evaluated outcomes of endoscopic drainage of malignant hilar strictures using optimal strategy and stents, and determined factors associated with stent patency, survival, and complications. Cross-sectional study was conducted at an academic center over 5 years. MFPS (10 French or 8.5 French) or open-cell SEMS were used for palliation of unresectable malignant hilar strictures, with imaging-targeted drainage of as many sectors as needed to drain >50% of viable liver volume. Risk factors were evaluated using regression analysis. The cumulative risk was assessed using Kaplan-Meier analysis. 77 patients with malignant hilar biliary strictures (median Bismuth IV) underwent targeted stenting (41 MFPS and 36 SEMS). Comparing MFPS vs. SEMS, technical success (95.1 vs. 97.2%, P=0.64), clinical success (75.6 vs. 83.3%, P=0.40), frequency of multiple stents (23/41 vs. 25/36, P=0.19), survival and adverse events were similar, but stent patency was significantly shorter (P<0.0001). Factors associated with survival were Karnofsky score and serum bilirubin level at presentation. Outcomes were independent of Bismuth class with acceptable results in Bismuth III and IV. Endoscopic biliary drainage with MFPS or open-cell SEMS targeting >50% of viable liver resulted in effective palliation in patients with complex malignant hilar biliary strictures. Patency was shorter in the MFPS group, but similar survival and complications were found when comparing MFPS and SEMS group.

  5. Development of Biliary and Enteral Stents by the Korean Gastrointestinal Endoscopists

    PubMed Central

    Shim, Chan Sup; Kim, Jin Hong; Bok, Gene Hyun

    2016-01-01

    Stenting in the gastrointestinal tract is a common procedure used for palliation of obstruction in the enteral and biliary tract. Today, stenting of malignant and benign strictures is performed at almost every major tertiary hospital in Korea. Moreover, Korea has become a major global supplier of cutting edge technology in the field of self-expanding metal stents. However, the history of stenting in Korea is relatively short and was far behind that of other nations such as Japan and Germany. The authors are humbled and gratified to have been able to observe the development and application of these stents in Korea, first hand. In this article, the authors review the overall history of stenting with a specific focus on the development of stenting in Korea. The development of esophageal, gastroduodenal, biliary, and colonic stents in Korea are reviewed in this article from a chronological and historical point of view, and a personal account of some of the significant moments of stent development in Korea are described. PMID:26956192

  6. Drug-eluting versus bare-metal coronary stents: where are we now?

    PubMed

    Amoroso, Nicholas S; Bangalore, Sripal

    2012-11-01

    Drug-eluting stents have dramatically reduced the risk of restenosis, but concerns of an increased risk of stent thrombosis have provided uncertainty about their use. Recent studies have continued to show improved procedural and clinical outcomes with drug-eluting stents both in the setting of acute coronary syndromes and stable coronary artery disease. Newer generation drug-eluting stents (especially everolimus-eluting stents) have been shown to be not only efficacious but also safe with reduced risk of stent thrombosis when compared with bare-metal stents, potentially changing the benchmark for stent safety from bare-metal stents to everolimus-eluting stents. While much progress is being made in the development of bioabsorbable polymer stents, nonpolymer stents and bioabsorbable stent technology, it remains to be seen whether these stents will have superior safety and efficacy outcomes compared with the already much improved rates of revascularization and stent thrombosis seen with newer generation stents (everolimus-eluting stents and resolute zotarolimus-eluting stents).

  7. A new fully covered metal stent for the treatment of benign and malignant dysphagia: a prospective follow-up study.

    PubMed

    Hirdes, Meike M C; Siersema, Peter D; Vleggaar, Frank P

    2012-04-01

    Fully covered self-expandable metal stents (FCSEMSs) are increasingly being used for malignant and benign strictures. Particularly in the latter, FCSEMSs are known for their high migration rates. A new FCSEMS with a dog-bone shape and internal covering was developed to reduce migration risk. To evaluate recurrent dysphagia and safety of the new FC stent in benign and malignant esophageal disorders. Prospective follow-up study. Tertiary referral center. Between November 2009 and February 2011, 48 consecutive patients (mean age 61 years, range 28-81 years) underwent FC stent placement for malignant (n = 33) or benign (n = 15) dysphagia. FC stent placement. Recurrent dysphagia and complications. Indications for FC stent placement included esophageal cancer (n = 28), extrinsic malignant compression (n = 4), recurrent malignancy after esophagectomy (n = 1), and refractory benign esophageal stricture (n = 15). In malignant strictures, recurrent dysphagia occurred in 5 patients (15%) because of stent migration (n = 3), tissue overgrowth (n = 1), and acute edema (n = 1). In benign strictures, stents were prematurely removed in 9 (60%) patients because of stent migration (n = 5), tissue overgrowth (n = 3), and pain (n = 1). Recurrent dysphagia occurred in all patients after stent removal. Major complications occurred in 10 patients (30%) with malignant strictures and in 3 patients (20%) with benign strictures and included severe pain and/or vomiting (n = 8), fistula formation (n = 2), bleeding (n = 2), and aspiration pneumonia (n = 1). Nonrandomized study design. Although the new FC stent effectively treats malignant dysphagia, it is associated with substantial major complications. In patients with refractory benign esophageal strictures, recurrent dysphagia occurs rapidly after removal of the new FC stent. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  8. Fracture and Collapse of Balloon-Expandable Stents in the Bilateral Common Iliac Arteries Due to Shiatsu Massage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ichihashi, Shigeo, E-mail: shigeoichihashi@yahoo.co.jp; Higashiura, Wataru; Itoh, Hirofumi

    2012-12-15

    We report a case of stent fracture and collapse of balloon-expandable stents caused by shiatsu massage. A 76-year-old man presented with complaints of intermittent claudication of the right lower extremity. Stenoses of the bilateral common iliac arteries (CIAs) were detected. Balloon-expandable stents were deployed in both CIAs, resulting in resolution of symptoms. Five months later, pelvis x-ray showed collapse of both stents. Despite the stent collapse, the patient was asymptomatic, and his ankle brachial index values were within the normal range. Further history showed that the patient underwent daily shiatsu therapy in the umbilical region, which may have triggered collapsemore » of the stent. Physicians should advise patients to avoid compression of the abdominal wall after implantation of a stent in the iliac artery.« less

  9. Endoscopic stenting in bile duct cancer increases liver volume.

    PubMed

    Lee, Chang Hun; Kim, Seong Hun; Kim, In Hee; Kim, Sang Wook; Lee, Soo Teik; Kim, Dae Ghon; Yang, Jae Do; Yu, Hee Chul; Cho, Baik Hwan; Lee, Seung Ok

    2014-09-01

    Objective evaluation tools for assessing the effectiveness of stenting in palliative treatment of malignant biliary obstruction are not satisfactory. Effects of biliary stenting on liver volume change have never been studied. We aimed to use volumetry to analyze liver volume changes after endoscopic stenting in bile duct cancer according to the location and number of stents. Retrospective review. University hospital. Patients with a diagnosis of hilar or distal bile duct cancer and who underwent biliary metal stenting. ERCP with self-expandable metal stent placement. Liver volume change after biliary stenting and its comparison according to the location (hilar vs distal common bile duct) and number (hilar bilateral vs hilar unilateral). There were 60 patients; 31 were treated for hilar bile duct cancer (13 for bilateral stent and 18 for unilateral stent) and 29 for distal bile duct cancer. Overall mean follow-up duration was 11.7 ± 4.9 weeks. Liver volume increased 17.4 ± 24.1%. The rate of liver growth was rapid during the early period from 4 to 8 weeks. Stenting in hilar bile duct cancer tended to increase liver volume more than distal biliary stents (22.5% vs 11.9%, P = .091). In hilar bile duct cancer, unilateral and bilateral stents showed similar liver volume increases (20.1% and 25.8%, respectively; P = .512). Single center, retrospective. Biliary stenting markedly increased liver volume in both hilar and distal bile duct cancer. Our data suggest that liver volume assessment could be a useful tool for evaluating stent efficacy. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  10. Iliocaval Confluence Stenting for Chronic Venous Obstructions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Graaf, Rick de, E-mail: r.de.graaf@mumc.nl; Wolf, Mark de, E-mail: markthewolf@gmail.com; Sailer, Anna M., E-mail: anni.sailer@mumc.nl

    PurposeDifferent techniques have been described for stenting of venous obstructions. We report our experience with two different confluence stenting techniques to treat chronic bi-iliocaval obstructions.Materials and MethodsBetween 11/2009 and 08/2014 we treated 40 patients for chronic total bi-iliocaval obstructions. Pre-operative magnetic resonance venography showed bilateral extensive post-thrombotic scarring in common and external iliac veins as well as obstruction of the inferior vena cava (IVC). Stenting of the IVC was performed with large self-expandable stents down to the level of the iliocaval confluence. To bridge the confluence, either self-expandable stents were placed inside the IVC stent (24 patients, SECS group) ormore » high radial force balloon-expandable stents were placed at the same level (16 patients, BECS group). In both cases, bilateral iliac extensions were performed using nitinol stents.ResultsRecanalization was achieved for all patients. In 15 (38 %) patients, a hybrid procedure with endophlebectomy and arteriovenous fistula creation needed to be performed because of significant involvement of inflow vessels below the inguinal ligament. Mean follow-up was 443 ± 438 days (range 7–1683 days). For all patients, primary, assisted-primary, and secondary patency rate at 36 months were 70, 73, and 78 %, respectively. Twelve-month patency rates in the SECS group were 85, 85, and 95 % for primary, assisted-primary, and secondary patency. In the BECS group, primary patency was 100 % during a mean follow-up period of 134 ± 118 (range 29–337) days.ConclusionStenting of chronic bi-iliocaval obstruction shows relatively high patency rates at medium follow-up. Short-term patency seems to favor confluence stenting with balloon-expandable stents.« less

  11. Fatigue and durability of Nitinol stents.

    PubMed

    Pelton, A R; Schroeder, V; Mitchell, M R; Gong, Xiao-Yan; Barney, M; Robertson, S W

    2008-04-01

    Nitinol self-expanding stents are effective in treating peripheral artery disease, including the superficial femoral, carotid, and renal arteries. However, fracture occurrences of up to 50% have been reported in some stents after one year. These stent fractures are likely due to in vivo cyclic displacements. As such, the cyclic fatigue and durability properties of Nitinol-based endovascular stents are discussed in terms of an engineering-based experimental testing program. In this paper, the combined effects of cardiac pulsatile fatigue and stent-vessel oversizing are evaluated for application to both stents and stent subcomponents. In particular, displacement-controlled fatigue tests were performed on stent-like specimens processed from Nitinol microtubing. Fatigue data were collected with combinations of simulated oversizing conditions and pulsatile cycles that were identified by computer modeling of the stent that mimic in vivo deformation conditions. These data are analyzed with non-linear finite element computations and are illustrated with strain-life and strain-based constant-life diagrams. The utility of this approach is demonstrated in conjunction with 10 million cycle pulsatile fatigue tests of Cordis SMART Control((R)) Nitinol self-expanding stents to calculate fatigue safety factors and thereby predict in vivo fatigue resistance. These results demonstrate the non-linear constant fatigue-life response of Nitinol stents, whereby, contrary to conventional engineering materials, the fatigue life of Nitinol is observed to increase with increasing mean strain.

  12. Treatment of Biliary Stricture After Live Donor Liver Transplantation With Combined Metal and Plastic Stent Insertion: A Feasibility and Safety Study.

    PubMed

    Parlak, Erkan; Koksal, Aydin Seref; Eminler, Ahmet Tarik; Toka, Bilal; Uslan, Mustafa Ihsan

    2017-08-01

    Fully covered self-expandable metal stents (Fc-SEMSs) have a challenging use in the treatment of anastomosis strictures after live donor liver transplantation (LDLT) because they can occlude secondary branch biliary ducts when placed above the biliary bifurcation. In this study, we evaluated the technical feasibility and safety of combining Fc-SEMSs with plastic stent(s) inserted to the secondary branch biliary ducts for the treatment of anastomosis stricture after LDLT. The study group included 22 patients (12 men, aged 51±11 years) with anastomotic biliary stricture after LDLT. A Fc-SEMS, 8 to 10 mm in diameter, was inserted to the straight, dilated main duct and plastic stent(s) were inserted to the secondary branches to avoid their occlusion. Stents were left in place for 2 months and removed with a stent retrieving forceps. Technical feasibilities, including technical success, successful removal, and adverse events of this novel strategy, were evaluated. Fc-SEMSs were successfuly deployed and removed in all of the cases. Three (13.6%) patients had pain requiring intravenous analgesia and Fc-SEMS had to be removed because of unbearable pain in one of them. Three (13.6%) patients developed cholangitis due to occlusion of unrecognized secondary branch biliary ducts. Primary stricture resolution rate was achieved in 17 (89.5%) of 19 patients. Recurrence was observed in 3 (17.6%) patients after a mean follow-up duration of 154.3±52.6 (range, 104-304) days. Combination of Fc-SEMS and plastic stent(s) is technically feasible and safe for the treatment of anastomotic biliary strictures after LDLT.

  13. Biliary metal stents for proximal esophageal or hypopharyngeal strictures.

    PubMed

    Bechtler, Matthias; Wagner, Florian; Fuchs, Erik-Sebastian; Jakobs, Ralf

    2015-11-01

    Endoscopic dilation is the standard of care for stenoses of the cervical esophagus, but refractory strictures require some form of stenting. Most endoscopists avoid the placement of metal stents near the upper esophageal sphincter as they can cause major problems like severe cervical pain and globus sensation. We report our results with the use of biliary SEMS in the upper esophagus, which have a smaller diameter than regular esophageal stents and therefore exert less expansive force. We retrospectively reviewed all patients in our center between July 2011 and June 2014 who received a biliary metal stent because of a refractory stricture in the cervical esophagus. We implanted biliary SEMS (Wallflex, Boston Scientific) with a diameter of 1 cm and length of 6-8 cm. Technical and clinical success, adverse events and duration of stenting were evaluated. Ten patients were treated with biliary SEMS in the upper esophagus. Strictures were located between 10 and 19 cm from incisor teeth. Stent placement was successful in all (10/10) patients. One stent had to be extracted because of pain and globus sensation. Apart from that stent tolerability was good. All remaining patients (9/9) reported improvement of dysphagia with a decrease in mean dysphagia score from 3.2 to 1.78. Mean duration of stenting was 68 days. Because of a high clinical success rate and good tolerability, biliary metal stents are a reasonable alternative for difficult strictures in the cervical esophagus, especially in the palliative setting.

  14. The Primary Patency and Fracture Rates of Self-Expandable Nitinol Stents Placed in the Popliteal Arteries, Especially in the P2 and P3 Segments, in Korean Patients

    PubMed Central

    Chang, Il Soo; Park, Sang Woo; Yun, Ik Jin; Hwang, Jae Joon; Lee, Song Am; Kim, Jun Seok; Chang, Seong-Hwan; Jung, Hong Geun

    2011-01-01

    Objective We wanted to evaluate the status of self-expandable nitinol stents implanted in the P2 and P3 segments of the popliteal artery in Korean patients. Materials and Methods We retrospectively analyzed 189 consecutive patients who underwent endovascular treatment for stenoocclusive lesions in the femoropopliteal artery from July 2003 to March 2009, and 18 patients who underwent stent placement in popliteal arterial P2 and P3 segments were finally enrolled. Lesion patency was evaluated by ultrasound or CT angiography, and stent fracture was assessed by plain X-rays at 1, 3, 6 and 12 months and annually thereafter. Results At the 1-month follow-up, stent fracture (Type 2) was seen in one limb (up to P3, 1 of 18, 6%) and it was identified in seven limbs at the 3-month follow-up (Type 2, Type 3, Type 4) (n = 1: up to P2; n = 6: P3). At the 6-month follow-up, one more fracture (Type 1) (up to P3) was noted. At the 1-year follow-up, there were no additional stent fractures. Just four limbs (up to P2) at the 2-year follow-up did not have stent fracture. The primary patency was 94%, 61% and 44% at 1, 3 and 6 months, respectively, and the group with stent implantation up to P3 had a higher fracture rate than that of the group that underwent stenting up to P2 (p < 0.05). Conclusion We suggest that stent placement up to the popliteal arterial P3 segment and over P2 in an Asian population can worsen the stent patency owing to stent fracture. It may be necessary to develop a stent design and structure for the Asian population that can resist the bending force in the knee joint. PMID:21430937

  15. Fatigue and In Vivo Validation of a Peritoneum-Lined Self-Expanding Nitinol Stent-Graft

    PubMed Central

    Bastijanic, Jennifer M.; Etscheidt, Jordan; Sattiraju, Mallika; Bonsignore, Craig; Kopchok, George; White, Rodney; Sarac, Timur P.

    2014-01-01

    Purpose To assess the fatigue and in vivo performance of a new stent-graft incorporating bovine peritoneum lining that is designed for application in peripheral vascular occlusive disease. Methods Bovine peritoneum-lined stent-grafts were subjected to accelerated in vitro pulsatile fatigue and axial/torsional fatigue testing designed to simulate 10 years of physiological strain on the devices. At specified times the devices were evaluated for stent fracture, suture failure, or tissue tearing. Seven dogs underwent bilateral common iliac artery (CIA) balloon angioplasty injury with unilateral placement of the peritoneum-lined stent-graft. Angiography and intravascular ultrasound were performed prior to treatment, after treatment, and prior to sacrifice at 30 days. Vessels were perfusion fixed and histologically evaluated at 5 regions: above stent, proximal stent, mid stent, distal stent, and below stent. Results No evidence of stent, suture, or tissue failure was present during or after pulsatile and axial/torsional fatigue testing. At 30±0.3 days after implantation, all vessels were patent. The average lumen area at explantation across stented vessels was 25.45 mm2. Lumen areas tended to be reduced above (23.57 mm2) and below (24.17 mm2) the stent. Lumen areas were consistent across stented regions at explantation (proximal stent 27.80 mm2, mid stent 25.88 mm2, and distal stent 25.81 mm2). The mean neointimal area in peritoneum-lined stents was 2.02±1.52 mm2, with a neointima:media ratio of 1.03±0.50. These values were significantly lower in the above and below stent areas than in the stented regions, but there was no difference in either measure within the proximal, mid, or distal stent. Conclusion The custom-designed peritoneum-lined stent-graft is promising for clinical peripheral applications due to its ability to resist relevant long-term physiological stresses and outstanding short-term patency rates in canine implantations. PMID:25290804

  16. Mechanical Characteristics of Composite Knitted Stents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tokuda, Takanori, E-mail: tkdtknr@gmail.com; Shomura, Yuzo; Tanigawa, Noboru

    2009-09-15

    We used metal wires and fibers to fabricate a composite knitted stent and then compare the mechanical characteristics of this stent with those of a pure metallic stent of the same construction in order to develop a stent that offers a comparable degree of expandability as metallic stents but can be used for highly curved lesions that cannot be treated using metallic stents. We fabricated two types of composite knitted stent (N-Z stents), using nitinol wire with a diameter of 0.12 mm and polypara-phenylene-benzobisoxazole (PBO) multifilament fiber (Zyron AS; Toyobo, Osaka, Japan). Stents were knitted into a cylindrical shape usingmore » the same textile pattern as a Strecker stent. Two loop lengths (L) of nitinol wire were used in the N-Z stents: L = 1.84 mm (N-Z stent L = 1.84) and L = 2.08 mm (N-Z stent L = 2.08). For the sake of comparison, we fabricated a metallic stent of nitinol using the same textile pattern (N-N stent L = 1.92). We applied a radial compression force diametrically to each stent and applied a bending force diametrically at the free end of a stent with one end fixed in order to evaluate the relationship between stent elasticity and load values. In addition, we macroscopically evaluated the generation of kinks when the stent was bent 180{sup o}. The radial compressive force when the stent diameter was reduced by 53% was 6.44 N in the case of N-Z stent L = 1.84, 6.14 N in the case of N-Z stent L = 2.08, and 4.96 N in the case of N-N stent L = 1.92 mm. The composite stent had a radial compressive force higher than that of a metallic stent. The restoring force to longitudinal direction at a 90{sup o} bending angle was 0.005 N for N-Z stent L = 1.84, 0.003 N for N-Z stent L = 2.08, and 0.034 N for N-N stent L = 1.92. The restoring force of the composite stent was significantly lower. Finally, the composite stent generated no definitive kinks at a bending angle of 180{sup o}, regardless of loop length. However, the N-N stent clearly produced kinks

  17. The effect of stent coating on stent deliverability: direct randomised comparison of drug eluting and bare metal stents using the same stent platform.

    PubMed

    Siminiak, Tomasz; Link, Rafał; Wołoszyn, Maciej; Kałmucki, Piotr; Baszko, Artur

    2012-01-01

    There is certain experimental and clinical evidence indicating that the covering of bare metal stents (BMS) with drug eluting polymers to produce drug eluting stents (DES) results in increased stent stiffness and modifies the mechanical properties of the stent platform. In addition, it has been speculated that the mechanical performance of DES, compared to BMS, may be related to the type of polymer used to cover stents. We aimed at evaluating the deliverability of DES with a lactate based biodegradable polymer and BMS in patients with stable coronary artery disease in a prospective randomised study. One hundred eleven consecutive patients (age: 36-77, mean 58.8 years) scheduled for routine angioplasty due to stable coronary disease were randomised to receive BMS (Chopin II(TM), Balton, Poland) or paclitaxel eluting stent (Chopin Luc(TM), Balton, Poland) using the same metal platform. Only patients scheduled for angioplasty using the direct implantation technique of a single stent were randomised. The exclusion criteria included patients 〉 80 years, multivessel disease and reference diameter of the target vessel 〉 3.5 mm. In the BMS group (n = 55; 35 males and 20 females), the mean diameter of implanted stents was 3.09 ± 0.40 and the mean length was 11.37 ± 2.80, whereas in the DES group (n = 56; 34 males and 22 females) the mean stent sizes were 3.02 ± 0.34 and 17.90 ± 7.38 mm, respectively (p 〉 0.05 for length). The groups did not significantly differ regarding the frequency of stent implantation to particular coronary vessels. The direct stenting technique was attempted and failed, leading to the stents' implantation after predilatation in five patients in the BMS group and six patients in the DES group. Failure of stent implantation and subsequent implantation of another stent type was observed in no BMS patients and in one DES patient (NS). Although stent covering with lactate based drug eluting polymer may increase its stiffness, it does not affect

  18. Fully covered Alimaxx esophageal metal stents in the endoscopic treatment of benign esophageal diseases.

    PubMed

    Senousy, Bahaa E; Gupte, Anand R; Draganov, Peter V; Forsmark, Chris E; Wagh, Mihir S

    2010-12-01

    Expandable esophageal stents are widely used for the palliation of dysphagia in patients with esophageal cancer and are also beginning to be used in patients with benign esophageal diseases such as refractory strictures and fistulas. There is concern regarding the increased risk of migration of the fully covered Alimaxx metal esophageal stent and experience with this stent in benign esophageal pathology has been reported in only a small series of patients. To evaluate the technical success in placement and removal, efficacy and complications of the Alimaxx esophageal stent for benign esophageal diseases. Our endoscopy database was retrospectively reviewed from 1/2003 to 2/2009 to identify patients with Alimaxx esophageal stent placement for benign diseases. Chart review was performed for age, gender, indication, site of the lesion, success of placement, outcome, and incidence of complications. Twenty-eight stents were successfully placed in 14 patients with benign esophageal diseases (mean: two stents/patient; range 1-7). Indications included esophageal fistula in seven (50%) and benign strictures in 7/14 (50%). Dysphagia improved in all patients while the fistula resolved in 6/7 (85.8%) patients. Complications related to stents included pain (2/28, 7%), stent related gastric ulcer (1/28, 4%), nausea and vomiting (3/21, 11%) and stent migration (11/28, 39%). All migrated stents were successfully endoscopically retrieved. The fully covered and removable Alimaxx stent is effective in the endoscopic management of benign esophageal strictures or fistulas, despite its relatively high rate of migration. Stent migration was successfully managed endoscopically without complications.

  19. Treatment of cerebral vasospasm with self-expandable retrievable stents: proof of concept.

    PubMed

    Bhogal, Pervinder; Loh, Yince; Brouwer, Patrick; Andersson, Tommy; Söderman, Michael

    2017-01-01

    To report our preliminary experience with the use of stent retrievers to cause vasodilation in patients with delayed cerebral vasospasm secondary to subarachnoid hemorrhage. Four patients from two different high volume neurointerventional centers developed cerebral vasospasm following subarachnoid hemorrhage. In addition to standard techniques for the treatment of cerebral vasospasm, we used commercially available stent retrievers (Solitaire and Capture stent retrievers) to treat the vasospastic segment including M2, M1, A2, and A1. We evaluated the safety of this technique, degree of vasodilation, and longevity of the effect. Stent retrievers can be used to safely achieve cerebral vasodilation in the setting of delayed cerebral vasospasm. The effect is long-lasting (>24 hours) and, in our initial experience, carries a low morbidity. We have not experienced any complications using this technique although we have noted that the radial force was not sufficient to cause vasodilation in some instances. The vasospasm did not return in the vessel segments treated with stent angioplasty in any of these cases. In two of our cases stent angioplasty resulted in the reversal of focal neurological symptoms. Stent retrievers can provide long-lasting cerebral vasodilation in patients with delayed cerebral vasospasm. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  20. Endoscopic stenting for hilar cholangiocarcinoma: efficacy of unilateral and bilateral placement of plastic and metal stents in a retrospective review of 480 patients

    PubMed Central

    2012-01-01

    Background Endoscopic biliary drainage of hilar cholangiocarcinoma is controversial with respect to the optimal types of stents and the extent of drainage. This study evaluated endoscopic palliation in patients with hilar cholangiocarcinoma using self-expandable metallic stents (SEMS) and plastic stents (PS).We also compared unilateral and bilateral stent placement according to the Bismuth classification. Methods Data on 480 patients receiving endoscopic biliary drainage for hilar cholangiocarcinoma between September 1995 and December 2010 were retrospectively reviewed to evaluate the following outcome parameters: technical success (TS), functional success (FS), early and late complications, stent patency and survival. Patients were followed from stent insertion until death or stent occlusion. Patients were divided into 3 groups according to the Bismuth classification (Group 1, type I; Group 2, type II; Group 3, type > III). Results The initial stent insertion was successful in 450 (93.8%) patients. TS was achieved in 204 (88.3%) patients treated with PS and in 246 (98.8%) patients palliated with SEMS (p < 0.001). In the intention-to-treat (ITT) analysis, the FS in patients treated with SEMS (97.9%) was significantly higher than in patients treated with PS (84.8%) (p < 0.001). Late complications occurred in 115 (56.4%) patients treated with PS and 60 (24.4%) patients treated with SEMS (p < 0.001). The median duration of stent patency in weeks (w) were as follows: 20 w in patients palliated with PS and 27 w in patients treated with SEMS (p < 0.0001). In Group 2, the median duration of PS patency was 17 w and 18 w for unilateral and bilateral placement, respectively (p = 0.0004); the median duration of SEMS patency was 24 w and 29 w for unilateral and bilateral placement, respectively (p < 0.0001). Multivariate analysis using the Poisson regression showed that SEMS placement (B = 0.48; P < 0.01) and bilateral deployment (B = 0

  1. Simulated training in colonoscopic stenting of colonic strictures: validation of a cadaver model.

    PubMed

    Iordache, F; Bucobo, J C; Devlin, D; You, K; Bergamaschi, R

    2015-07-01

    There are currently no available simulation models for training in colonoscopic stent deployment. The aim of this study was to validate a cadaver model for simulation training in colonoscopy with stent deployment for colonic strictures. This was a prospective study enrolling surgeons at a single institution. Participants performed colonoscopic stenting on a cadaver model. Their performance was assessed by two independent observers. Measurements were performed for quantitative analysis (time to identify stenosis, time for deployment, accuracy) and a weighted score was devised for assessment. The Mann-Whitney U-test and Student's t-test were used for nonparametric and parametric data, respectively. Cohen's kappa coefficient was used for reliability. Twenty participants performed a colonoscopy with deployment of a self-expandable metallic stent in two cadavers (groups A and B) with 20 strictures overall. The median time was 206 s. The model was able to differentiate between experts and novices (P = 0. 013). The results showed a good consensus estimate of reliability, with kappa = 0.571 (P < 0.0001). The cadaver model described in this study has content, construct and concurrent validity for simulation training in colonoscopic deployment of self-expandable stents for colonic strictures. Further studies are needed to evaluate the predictive validity of this model in terms of skill transfer to clinical practice. Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.

  2. Endoscopic ultrasound-guided biliary drainage using a newly designed metal stent with a thin delivery system: a preclinical study in phantom and porcine models.

    PubMed

    Minaga, Kosuke; Kitano, Masayuki; Itonaga, Masahiro; Imai, Hajime; Miyata, Takeshi; Yamao, Kentaro; Tamura, Takashi; Nuta, Junya; Warigaya, Kenji; Kudo, Masatoshi

    2017-12-08

    This study was designed to evaluate the feasibility and safety of a newly designed self-expandable metal stent for endoscopic ultrasound-guided biliary drainage (EUS-BD) when it was delivered via three different stent delivery systems: a 7.5Fr delivery catheter with a bullet-shaped tip (7.5Fr-bullet), a 7Fr catheter with a bullet-shaped tip (7Fr-bullet), or a 7Fr catheter with a tee-shaped tip (7Fr-tee). This experimental study utilized a porcine model of biliary dilatation involving ten pigs. In the animal study, technical feasibility and clinical outcomes of the stent when placed with each of the delivery systems were examined. In addition, a phantom model was used to measure the resistance of these delivery systems to advancement. Phantom experiments showed that, compared with 7Fr-bullet, 7Fr-tee had less resistance force to the advancement of the stent delivery system. EUS-BD was technically successful in all ten pigs. Fistulous tract dilation was necessary in 100% (2/2), 75% (3/4), and 0% (0/4) of the pigs that underwent EUS-BD using 7.5Fr-bullet, 7Fr-bullet, and 7Fr-tee, respectively. There were no procedure-related complications. Our newly designed metal stent may be feasible and safe for EUS-BD, particularly when delivered by 7Fr-tee, because it eliminates the need for fistulous tract dilation.

  3. Gastric ulceration following oesophageal stent migration complicating surgical management of oesophageal cancer

    PubMed Central

    Markar, Sheraz R.; Ross, Andrew; Low, Donald E.

    2012-01-01

    Oesophageal, fully covered self-expanding metal stents (SEMS) allow palliation of dysphagia so as to support nutrition during neoadjuvant therapy. We present a 68-year old man with an oesophageal adenocarcinoma (T3N1M0) who had a fully covered oesophageal SEMS placed prior to neoadjuvant chemoradiotherapy. Repeat endoscopy 8 weeks later (for stent removal) showed that the stent had migrated and impacted upon the greater curvature of the stomach with a resultant ulcer. Surgery was delayed and, 10 weeks following the cessation of neoadjuvant chemoradiotherapy, this patient underwent a right thoracoabdominal oesophagogastrectomy. Operative findings included an erosion of the stent-induced gastric ulcer into the body of the pancreas and showed that the ulcerated tumour had become adherent to the thoracic aorta. This report demonstrates that the complications of stent migration can significantly impact upon surgical resection at multiple levels and provides a case for the routine removal of stents used in the neoadjuvant setting. PMID:22593562

  4. Stent implantation into the tracheo-bronchial system in rabbits: histopathologic sequelae in bare metal vs. drug-eluting stents.

    PubMed

    Sigler, Matthias; Klötzer, Julia; Quentin, Thomas; Paul, Thomas; Möller, Oliver

    2015-12-01

    Stent implantation into the tracheo-bronchial system may be life-saving in selected pediatric patients with otherwise intractable stenosis of the upper airways. Following implantation, significant tissue proliferation may occur, requiring re-interventions. We sought to evaluate the effect of immunosuppressive coating of the stents on the extent of tissue proliferation in an animal model. Bare metal and sirolimus-coated stents (Bx Sonic and Cypher Select, Johnson & Johnson, Cordis) were implanted into non-stenotic lower airways of New Zealand white rabbits (weight 3.1 to 4.8 kg). Three stents with sirolimus coating and six bare metal stents could be analyzed by means of histology and immunohistochemistry 12 months after implantation. On a macroscopic evaluation, all stents were partially covered with a considerable amount of whitish tissue. Histologically, these proliferations contained fiber-rich connective tissue and some fibromuscular cells without significant differences between both stent types. The superficial tissue layer was formed by typical respiratory epithelium and polygonal cells. Abundant lymphocyte infiltrations and moderate granulocyte infiltrations were found in both groups correspondingly, whereas foreign-body reaction was more pronounced around sirolimus-eluting stents. After stent implantation in the tracheo-bronchial system of rabbits, we found tissue reactions comparable to those seen after stent implantation into the vascular system. There was no difference between coated and uncoated stents with regard to quality and quantity of tissue proliferation. We found, however, a significantly different inflammatory reaction with a more pronounced foreign-body reaction in sirolimus-coated stents. In our small series, drug-eluting stents did not exhibit any benefit over bare metal stents in an experimental setting.

  5. Bare metal stents, durable polymer drug eluting stents, and biodegradable polymer drug eluting stents for coronary artery disease: mixed treatment comparison meta-analysis

    PubMed Central

    Toklu, Bora; Amoroso, Nicholas; Fusaro, Mario; Kumar, Sunil; Hannan, Edward L; Faxon, David P; Feit, Frederick

    2013-01-01

    Objective To compare the efficacy and safety of biodegradable polymer drug eluting stents with those of bare metal stents and durable polymer drug eluting stents. Design Mixed treatment comparison meta-analysis of 258 544 patient years of follow-up from randomized trials. Data sources and study selection PubMed, Embase, and Central were searched for randomized trials comparing any of the Food and Drug Administration approved durable polymer drug eluting stents (sirolimus eluting, paclitaxel eluting, cobalt chromium everolimus eluting, platinum chromium everolimus eluting, zotarolimus eluting-Endeavor, and zotarolimus eluting-Resolute) or biodegradable polymer drug eluting stents, with each other or against bare metal stents. Outcomes Long term efficacy (target vessel revascularization, target lesion revascularization) and safety (death, myocardial infarction, stent thrombosis). Landmark analysis at more than one year was evaluated to assess the potential late benefit of biodegradable polymer drug eluting stents. Results From 126 randomized trials and 258 544 patient years of follow-up, for long term efficacy (target vessel revascularization), biodegradable polymer drug eluting stents were superior to paclitaxel eluting stents (rate ratio 0.66, 95% credibility interval 0.57 to 0.78) and zotarolimus eluting stent-Endeavor (0.69, 0.56 to 0.84) but not to newer generation durable polymer drug eluting stents (for example: 1.03, 0.89 to 1.21 versus cobalt chromium everolimus eluting stents). Similarly, biodegradable polymer drug eluting stents were superior to paclitaxel eluting stents (rate ratio 0.61, 0.37 to 0.89) but inferior to cobalt chromium everolimus eluting stents (2.04, 1.27 to 3.35) for long term safety (definite stent thrombosis). In the landmark analysis after one year, biodegradable polymer drug eluting stents were superior to sirolimus eluting stents for definite stent thrombosis (rate ratio 0.29, 0.10 to 0.82) but were associated with increased

  6. Tracheomalacia treatment using a large-diameter, custom-made airway stent in a case with mounier-kuhn syndrome.

    PubMed

    Ozdemir, Cengiz; Sökücü, Sinem Nedime; Karasulu, Levent; Altın, Sedat; Dalar, Levent

    2014-01-01

    Mounier-Kuhn Syndrome (MKS) is a rare congenital disease that presents with abnormal enlargement in the central airways. In MKS, tracheomegaly is accompanied by difficulty in expelling recurrent lung infections and bronchiectasia. We presented a patient with MKS where commercially made stents were inadequate for stabilization and a custom-made, self-expandable metallic stent with a diameter of 28 mm and length of 100 mm was used. Chest pain that was thought to develop due to the stent and that disappeared after stent removal may be considered the main complication leading to stent removal. Continuous positive airway pressure therapy (CPAP) therapy was planned for the control of symptoms, which re-emerged after stent removal. This case is presented as an example that complications developing due to the stent as well as patient noncompliance may lead to stent removal, even when useful results are obtained from treatment of MKS.

  7. Nitinol Esophageal Stents: New Designs and Clinical Indications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Strecker, Ernst-Peter; Boos, Irene; Vetter, Sylvia

    1996-11-15

    Purpose: To evaluate the clinical use of covered and noncovered, knitted nitinol stents in patients presenting new stent indications. Methods: Self-expandable, knitted nitinol stents were implanted in four patients for treatment of dysphagia. In two patients who had malignant strictures and had esophago-respiratory fistulae and in one patient with an esophagocutaneous fistula, polytetrafluoroethylene (PTFE)-covered stents were implanted. One patient received a noncovered stent, but a retrograde approach through a percutaneous endoscopic gastrostomy (PEG) fistula had to be chosen for recanalization of an esophageal occlusion. Two patients received stents for treatment of benign strictures. Results: Recanalization of the stricture and stentmore » implantation were performed under fluoroscopic control without any procedure-related morbidity or mortality. Dysphagia improved in all patients and the esophageal fistulae could be sealed off by covered stents. During a maximum follow-up of 18 months, there was no stent migration or esophageal perforation. Complications observed were stent stenosis due to food impaction (1/4) and benign stent stenosis (2/2). Most complications could be treated by the interventional radiologist. Conclusion: Self-expandable, covered Nitinol stents provide an option for the treatment of dysphagia combined with esophageal fistulae. In combination with interventional radiology techniques, even complex strictures are accessible. For benign strictures, the value of stent treatment has not yet been proven.« less

  8. Endoscopic bilio-duodenal bypass: outcomes of primary and revision efficacy of combined metallic stents in malignant duodenal and biliary obstructions.

    PubMed

    Canena, Jorge; Coimbra, João; Carvalho, Diana; Rodrigues, Catarina; Silva, Mário; Costa, Mariana; Horta, David; Mateus Dias, António; Seves, Isabel; Ramos, Gonçalo; Ricardo, Leonel; Coutinho, António Pereira; Romão, Carlos; Veiga, Pedro Mota

    2014-11-01

    Self-expandable metal stents (SEMSs) can be used for palliation of combined malignant biliary and duodenal obstructions. However, the results of the concomitant stent placement for the duration of the patients' lives, as well as the need for and efficacy of endoscopic revision, are unclear. This study evaluated the clinical effectiveness of SEMS placement for combined biliary and duodenal obstructions throughout the patients' lives and the need for endoscopic revision. This study is a retrospective multicenter study of 50 consecutive patients who underwent simultaneous or sequential SEMS placement for malignant biliary and duodenal obstructions. The data were collected to analyze the sustained relief of obstructive symptoms until the patients' death and the efficacy of endoscopic revision, as well as stent patency, adverse events, survival and prognostic factors for stent patency. Technical and immediate clinical success was achieved in all of the patients. Duodenal stricture occurred before the papilla in 35 patients (70 %), involved the papilla in 11 patients (22 %) and was observed distal to the papilla in four patients (8 %). Initial biliary stenting was performed endoscopically in 42 patients (84 %) and percutaneously in eight patients. After combined stenting, 30 patients (60 %) required no additional intervention until the time of their death. The remaining 20 patients were successfully treated using endoscopic stent reinsertion: nine patients needed biliary revision, three patients needed duodenal restenting and eight patients needed both biliary and duodenal reinsertion. The median duodenal stent patency and median biliary stent patency were 34 and 27 weeks, respectively. The median survival after combined stent placement was 18 weeks. A Cox multivariate analysis showed that duodenal stent obstruction after combined stenting was a risk factor for biliary stent obstruction (hazard ratio 6.85; 95 % confidence interval 1.43-198.98; P = 0

  9. Gianturco-Rösch Z stents in tracheobronchial stenoses.

    PubMed

    Petersen, B D; Uchida, B T; Barton, R E; Keller, F S; Rösch, J

    1995-01-01

    To evaluate expandable metallic Gianturco-Rösch Z (GRZ) stents for treatment of benign and malignant tracheobronchial stenoses. Six patients, ages 45-73 years, were treated for severe dyspnea with placement of GRZ stents. Three patients had benign tracheal lesions (one tracheomalacia, two postoperative) and received uncovered GRZ stents. Three patients had malignant stenoses at the level of the carina; one received an uncovered stent and the other two received silicone-covered GRZ stents. Two patients with benign lesions responded well to stent placement. One was asymptomatic for a year and then was lost to follow-up; the other improved substantially but died of end-stage lung disease 5 months after stent placement. A third patient with a benign high tracheal lesion did poorly; symptoms recurred secondary to inferior migration of a stent, which was removed surgically at 4 months. All patients with malignant lesions improved symptomatically after stent placement and remained without significant dyspnea until death (from 1 to 6 months). Expandable GRZ stents are promising devices for treatment of benign lesions and offer effective palliation of malignant tracheobronchial stenoses.

  10. [Eleven Patients with Gastric Cancer Who Received Chemotherapy after Stent Placement for Gastric Outlet Obstruction].

    PubMed

    Endo, Shunji; Nakagawa, Tomo; Konishi, Ken; Ikenaga, Masakazu; Ohta, Katsuya; Nakashima, Shinsuke; Matsumoto, Kenichi; Nishikawa, Kazuhiro; Ohmori, Takeshi; Yamada, Terumasa

    2017-01-01

    Endoscopic placement of self-expandable metallic stents is reportedly effective for gastric outlet obstructions due to advanced gastric cancer, and is less invasive than gastrojejunostomy. For patients who have good performance status, we administer chemotherapy after stent placement, although the safety and feasibility of this chemotherapy have not yet been discussed in full. Between 2011 and 2015, 15 patients at our institution underwent endoscopic gastroduodenal stent placement for gastric outlet obstruction due to gastric cancer. Eleven of these patients were administered chemotherapy after stent placement. In our case series, we did not observe any specific adverse event caused by stent placement plus chemotherapy. Adverse events after chemotherapy included anemia of CTCAE Grade 3 in 7 patients. Stent-in-stent placement was needed in 2 patients. Neither stent migration nor perforation was observed. Therefore, chemotherapy after stent placement for gastric outlet obstruction due to gastric cancer was considered safe and feasible. Stent placement is useful not only as palliative care for patients with terminal-stage disease, but also as one of the multimodal therapeutic strategies for gastric cancer.

  11. Direct comparison of coronary bare metal vs. drug-eluting stents: same platform, different mechanics?

    PubMed

    Schmidt, Wolfram; Lanzer, Peter; Behrens, Peter; Brandt-Wunderlich, Christoph; Öner, Alper; Ince, Hüseyin; Schmitz, Klaus-Peter; Grabow, Niels

    2018-01-08

    Drug-eluting stents (DES) compared to bare metal stents (BMS) have shown superior clinical performance, but are considered less suitable in complex cases. Most studies do not distinguish between DES and BMS with respect to their mechanical performance. The objective was to obtain mechanical parameters for direct comparison of BMS and DES. In vitro bench tests evaluated crimped stent profiles, crossability in stenosis models, elastic recoil, bending stiffness (crimped and expanded), and scaffolding properties. The study included five pairs of BMS and DES each with the same stent platforms (all n = 5; PRO-Kinetic Energy, Orsiro: BIOTRONIK AG, Bülach, Switzerland; MULTI-LINK 8, XIENCE Xpedition: Abbott Vascular, Temecula, CA; REBEL Monorail, Promus PREMIER, Boston Scientific, Marlborough, MA; Integrity, Resolute Integrity, Medtronic, Minneapolis, MN; Kaname, Ultimaster: Terumo Corporation, Tokyo, Japan). Statistical analysis used pooled variance t tests for pairwise comparison of BMS with DES. Crimped profiles in BMS groups ranged from 0.97 ± 0.01 mm (PRO-Kinetic Energy) to 1.13 ± 0.01 mm (Kaname) and in DES groups from 1.02 ± 0.01 mm (Orsiro) to 1.13 ± 0.01 mm (Ultimaster). Crossability was best for low profile stent systems. Elastic recoil ranged from 4.07 ± 0.22% (Orsiro) to 5.87 ± 0.54% (REBEL Monorail) including both BMS and DES. The bending stiffness of crimped and expanded stents showed no systematic differences between BMS and DES neither did the scaffolding. Based on in vitro measurements BMS appear superior to DES in some aspects of mechanical performance, yet the differences are small and not class uniform. The data provide assistance in selecting the optimal system for treatment and assessment of new generations of bioresorbable scaffolds. not applicable.

  12. Fabrication and in vitro deployment of a laser-activated shape memory polymer vascular stent

    PubMed Central

    Baer, Géraldine M; Small, Ward; Wilson, Thomas S; Benett, William J; Matthews, Dennis L; Hartman, Jonathan; Maitland, Duncan J

    2007-01-01

    Background Vascular stents are small tubular scaffolds used in the treatment of arterial stenosis (narrowing of the vessel). Most vascular stents are metallic and are deployed either by balloon expansion or by self-expansion. A shape memory polymer (SMP) stent may enhance flexibility, compliance, and drug elution compared to its current metallic counterparts. The purpose of this study was to describe the fabrication of a laser-activated SMP stent and demonstrate photothermal expansion of the stent in an in vitro artery model. Methods A novel SMP stent was fabricated from thermoplastic polyurethane. A solid SMP tube formed by dip coating a stainless steel pin was laser-etched to create the mesh pattern of the finished stent. The stent was crimped over a fiber-optic cylindrical light diffuser coupled to an infrared diode laser. Photothermal actuation of the stent was performed in a water-filled mock artery. Results At a physiological flow rate, the stent did not fully expand at the maximum laser power (8.6 W) due to convective cooling. However, under zero flow, simulating the technique of endovascular flow occlusion, complete laser actuation was achieved in the mock artery at a laser power of ~8 W. Conclusion We have shown the design and fabrication of an SMP stent and a means of light delivery for photothermal actuation. Though further studies are required to optimize the device and assess thermal tissue damage, photothermal actuation of the SMP stent was demonstrated. PMID:18042294

  13. Stage of hilar cholangiocarcinoma predicts recurrence of biliary obstruction in patients with metal stents.

    PubMed

    Siddiqui, Ali; Shahid, Haroon; Sarkar, Avik; Cox, Kristen; Kowalski, Thomas E; Loren, David E; Sharma, Ashish; Laing, Patrick; Birch, Madeline; Adler, Douglas G

    2013-09-01

    Most patients with hilar cholangiocarcinomas present with unresectable tumors, so only palliative biliary drainage with self-expanding metal stents (SEMS) is possible. Stents eventually cease to function because of tumor overgrowth and/or other causes, so it is important to identify factors that affect stent patency and failure. We examined the patency of endoscopically placed SEMS in patients with hilar cholangiocarcinoma and factors associated with patency. We performed a retrospective study of 120 consecutive patients (mean age, 67 ± 14.6 years; 74 male) who presented with obstructive jaundice from hilar cholangiocarcinoma and underwent bilateral SEMS from September 2006 through April 2012 at 2 US tertiary medical centers. We collected data on patient demographics and survival, success of stent placement and function, and immediate adverse events. The primary outcome was duration of stent patency (time from insertion to failure). Thirty-eight patients had stage 1 hilar cholangiocarcinomas, 45 had stage 2, 12 had stage 3, and 25 had stage 4. The median length of the hilar stricture was 9 mm (range, 8-50 mm). The stent was successfully passaged across the stricture in all patients and was functional in 115; its median length was 8 mm (range, 8-10 mm), and diameter was 80 mm (range, 60-100 mm). Fourteen patients had immediate adverse events, including perforation (n = 2), bleeding (n = 2), pancreatitis (n = 9), and cholangitis (n = 1). Median survival was 17 weeks (range, 1-211 weeks), and 50 patients had stent occlusion. On Kaplan-Meier analysis, the median time from stent placement to occlusion was 17 weeks (range, 1-104 weeks). More patients with stage 3 or 4 tumors (64%) had SEMS occlusion than patients with stage 1 or 2 tumors (28%) in univariate analysis (P = .017). In multivariate analysis, only cancer stage was independently and significantly associated with patency (P = .006; hazard ratio, 2.77); age, sex, length of stricture, and SEMS diameter and

  14. Biodegradable metals for cardiovascular stents: from clinical concerns to recent Zn - alloys

    PubMed Central

    Bowen, Patrick K.; Shearier, Emily R.; Zhao, Shan; Guillory, Roger J.; Zhao, Feng; Goldman, Jeremy; Drelich, Jaroslaw W.

    2016-01-01

    Metallic stents are commonly used to promote revascularization and maintain patency of plaqued or damaged arteries following balloon angioplasty. To mitigate the long-term side effects associated with corrosion-resistant stents (i.e. chronic inflammation and late stage thrombosis), a new generation of so-called “bioabsorbable” stents is currently being developed. The bioabsorbable coronary stents will corrode and be absorbed by the artery after completing their task as vascular scaffolding. Research spanning the last two decades has focused on biodegradable polymeric, iron-based, and magnesium-based stent materials. The inherent mechanical and surface properties of metals make them more attractive stent material candidates than their polymeric counterparts. Unfortunately, iron produces a voluminous, retained oxide product in the arterial wall, whereas magnesium and its alloys corrode too rapidly. A third class of metallic bioabsorbable materials that are based on zinc has been introduced in the last few years. As summarized in this contribution, this new zinc-based class of materials demonstrates the potential for an absorbable metallic stent with the mechanical and biodegradation characteristics required for optimal stent performance. They appear to be free of flaws that limit the application of iron- and magnesium-based alloys, and polymers. This review compares bioabsorbable materials and summarizes progress towards bioabsorbable stents. It emphasizes on current understanding of physiological and biological benefits of zinc and its biocompatibility. Finally, the review provides an outlook on challenges in designing zinc-based stents of optimal mechanical properties and biodegradation rate. PMID:27094868

  15. Migrated esophageal stent posing a challenge for ventilation.

    PubMed

    D'souza, Nita; Arbhi, Sachin; Dikshit, Amit; Ghadge, Murarji; Jha, Smriti

    2017-01-01

    Self-expandable esophageal stents are being commonly used for palliative treatment in advanced esophageal cancer patients to relieve dysphagia, prevent tracheoesophageal fistula, and facilitate symptomatic betterment. The modern covered stents reduce the ingrowth of the tumor but have seen an increase in the incidence of stent migrations. We report a rather complicated presentation of an esophageal stent for esophageal dilatation and a challenging management of a difficult tracheostomy.

  16. Tracheomalacia Treatment Using a Large-Diameter, Custom-Made Airway Stent in a Case with Mounier-Kuhn Syndrome

    PubMed Central

    Özdemir, Cengiz; Sökücü, Sinem Nedime; Karasulu, Levent; Altın, Sedat; Dalar, Levent

    2014-01-01

    Mounier-Kuhn Syndrome (MKS) is a rare congenital disease that presents with abnormal enlargement in the central airways. In MKS, tracheomegaly is accompanied by difficulty in expelling recurrent lung infections and bronchiectasia. We presented a patient with MKS where commercially made stents were inadequate for stabilization and a custom-made, self-expandable metallic stent with a diameter of 28 mm and length of 100 mm was used. Chest pain that was thought to develop due to the stent and that disappeared after stent removal may be considered the main complication leading to stent removal. Continuous positive airway pressure therapy (CPAP) therapy was planned for the control of symptoms, which re-emerged after stent removal. This case is presented as an example that complications developing due to the stent as well as patient noncompliance may lead to stent removal, even when useful results are obtained from treatment of MKS. PMID:25276462

  17. Clinical Outcomes, Efficacy, and Adverse Events in Patients Undergoing Esophageal Stent Placement for Benign Indications: A Large Multicenter Study.

    PubMed

    Suzuki, Takayuki; Siddiqui, Ali; Taylor, Linda J; Cox, Kristen; Hasan, Raza A; Laique, Sobia N; Mathew, Arun; Wrobel, Piotr; Adler, Douglas G

    2016-01-01

    Esophageal stents are commonly used to treat benign esophageal conditions including refractory benign esophageal strictures, anastomotic strictures, fistulae, perforations and anastomotic leaks. Data on outcomes in these settings remain limited. We performed a retrospective multicenter study of patients who underwent fully or partially covered self-expandable stent placement for benign esophageal diseases. Esophageal stent placements were performed for the following indications: (1) benign refractory esophageal strictures, (2) surgical anastomotic strictures, (3) esophageal perforations, (4) esophageal fistulae, and (5) surgical anastomotic leaks. A total of 70 patients underwent esophageal stent placement for benign esophageal conditions. A total of 114 separate procedures were performed. The most common indication for esophageal stent placement was refractory benign esophageal stricture (48.2%). Global treatment success rate was 55.7%. Treatment success rate was 33.3% in refractory benign strictures, 23.1% in anastomotic strictures, 100% in perforations, 71.4% in fistulae, and 80% in anastomotic leaks. Stent migration was noted in 28 of 70 patients (40%), most commonly seen in refractory benign strictures. This is one of the largest studies to date of esophageal stents to treat benign esophageal diseases. Success rates are lowest in benign esophageal strictures. These patients have few other options beyond chronic dilations, feeding tubes, and surgery, and fully covered self-expandable metallic stent give patients a chance to have their problem fixed endoscopically and still eat by mouth. Perforations, fistulas, and leaks respond very well to esophageal stenting, and stenting should be considered as a first-line therapy in these settings.

  18. Application of memory metallic stents to urinary tract disorders in pediatric patients.

    PubMed

    Kamata, Shinkichi; Usui, Noriaki; Kamiyama, Masafumi; Yoneda, Akihiro; Tazuke, Yuko; Ooue, Takaharu

    2005-03-01

    The use of memory metallic stents for the urinary tract in pediatric patients has not been reported. The authors report on 2 patients with urinary tract disorders who were successfully treated with a memory metallic stent. A thermoexpandable, nickel-titanium alloy stent was placed at the urethroureteral junction of a 4-year-old boy with ureteral stenosis associated with cloacal exstrophy for 18 months and at the urethra of a 2-year-old girl with ischuria after a repair of cloacal anomaly for 6 months. Temporary insertion of a memory metallic stent is a safe and effective alternative for organic stricture or functional obstruction of the urinary tract in pediatric patients.

  19. Mechanical Interaction of an Expanding Coiled Stent with a Plaque-Containing Arterial Wall: A Finite Element Analysis.

    PubMed

    Welch, Tré R; Eberhart, Robert C; Banerjee, Subhash; Chuong, Cheng-Jen

    2016-03-01

    Wall injury is observed during stent expansion within atherosclerotic arteries, related in part to stimulation of the inflammatory process. Wall stress and strain induced by stent expansion can be closely examined by finite element analysis (FEA), thus shedding light on procedure-induced sources of inflammation. The purpose of this work was to use FEA to examine the interaction of a coiled polymer stent with a plaque-containing arterial wall during stent expansion. An asymmetric fibrotic plaque-containing arterial wall model was created from intravascular ultrasound (IVUS) images of a diseased artery. A 3D model for a coil stent at unexpanded state was generated in SolidWorks. They were imported into ANSYS for FEA of combined stent expansion and fibrotic plaque-distortion. We simulated the stent expansion in the plaqued lumen by increasing balloon pressure from 0 to 12 atm in 1 atm step. At increasing pressure, we examined how the expanding stent exerts forces on the fibrotic plaque and vascular wall components, and how the latter collectively resist and balance the expansive forces from the stent. Results show the expanding coiled stent creates high stresses within the plaque and the surrounding fibrotic capsule. Lower stresses were observed in adjacent medial and adventitial layers. High principal strains were observed in plaque and fibrotic capsule. The results suggest fibrotic capsule rupture might occur at localized regions. The FEA/IVUS method can be adapted for routine examination of the effects of the expansion of selected furled stents against IVUS-reconstructed diseased vessels, to improve stent deployment practices.

  20. Antral localization worsens the efficacy of enteral stents in malignant digestive tumors.

    PubMed

    Dolz, Carlos; Vilella, Àngels; González Carro, Pedro; González Huix, Ferran; Espinós, Juan Carlos; Santolaria, Santos; Pérez Roldán, Francisco; Figa, Montserrat; Loras, Carmen; Andreu, Hernán

    2011-02-01

    Malignant gastric outlet obstruction can be treated by means of enteral stenting or surgical gastrojejunalanatomosis. We evaluated in a prospective and multicentre study the efficacy of the enteral stent on food intake, the quality of life impact, and the relationship between efficacy and determined clinical and technical parameters. Seventy one patients affected by symptoms arising from gastroduodenal obstruction due to malignant tumors, with criteria of irresecability, metastatic disease or very high surgical risk, were treated by means of self expanding metal stents. We used the GOOSS index to evaluate efficacy, and the Euro Qol-5D index to evaluate quality of life. Before stenting patients with GOOSS 0 and 1 were 68 (98.5%). After stenting patients with GOOSS 2 and 3 (semisolid and solid food) were 58 (84,1%) (P<.0001). The Euro Qol-5D index measured before and a month after stenting were 10.17 and 10.04 respectively (P=.6). The median survival was 91 days (9-552). The enteral stents for localised tumors in the duodenum and the gastrojejunalanastomosis were effective in 26 patients (70.2%) and 13 patients respectively (86.6%), while the enteral stents of tumors in the antrum were effective in only 5 patients (29.4%). The palliative treatment of malignant gastric outlet obstruction with a uncovered metal stent produces a significant improvement of oral food intake and maintains the overall quality of life index. The antral localization is associated with a lower efficacy of the procedure. Copyright © 2010 Elsevier España, S.L. All rights reserved.

  1. Interventional radiology and the use of metal stents in nonvascular clinical practice: a systematic overview.

    PubMed

    Pron, G; Common, A; Simons, M; Ho, C S

    1999-05-01

    The intent of this systematic overview was to describe the clinical role of metal stents in nonvascular health care interventions and the level of evidence supporting their use. Structured searches of Medline were conducted and limited to original peer-reviewed articles published in English. Clinical practice involving metal stents was reported in more than 109 clinical series involving 4,753 patients. Stents were placed mainly for palliation of malignant biliary, esophageal, and airway obstruction in patients who were untreatable or had surgically unresectable lesions. Assessment of these interventions has so far centered on safety and technical success. Efficacy, quality of life, and costing factors were not routinely reported. Randomized trial evidence was available but limited; six randomized trials involving metal stents have been reported. Three trials involved biliary malignant obstruction, and all three reported metal stent (132 patients) palliation to be superior to plastic stent palliation (136 patients) based on longer patency and lower reintervention costs. Safety and complication differences between stents, however, were inconsistent across trials. In three trials involving esophageal malignant obstruction, metal stent (82 patients) palliation was reported to be superior to plastic stent (41 patients), based on lower complication and reintervention rates, and superior to laser therapy (18 patients), based on better dysphagia relief. Use of metal stents has been reported for obstructed ducts and passageways of most body systems. There is, however, limited controlled trial evidence confirming the advantages of their use over plastic stents or other forms of treatment.

  2. Orbital atherectomy as an adjunct to debulk difficult calcified lesions prior to mesenteric artery stenting.

    PubMed

    Manunga, Jesse M; Oderich, Gustavo S

    2012-08-01

    To describe a technique in which percutaneous orbital atherectomy is used to debulk heavily calcified superior mesenteric artery (SMA) occlusions as an adjunct in patients undergoing angioplasty and stenting. The technique is demonstrated in a 62-year-old woman with a replaced right hepatic artery originating from an SMA occluded by densely calcified lesions. Via a left transbrachial approach, a 7-F MPA guide catheter was used to engage the ostium of the SMA, which was crossed using a catheter and guidewire. The calcified lesion was debulked using the 2-mm Diamondback 360° orbital atherectomy system. The wire was exchanged for a 0.014-inch filter wire and 0.018-inch guidewire. Using a 2-guidewire technique, the SMA was stented with a self-expanding stent for the distal lesion that crossed side branches and a balloon-expandable stent at the ostium. A 0.014-inch guidewire was placed into the replaced hepatic artery through a cell of the self-expanding stent, followed by deployment of a small balloon-expandable stent to address the residual lesion. The use of orbital atherectomy to debulk occluded and heavily calcified SMA lesions may optimize the technical results with angioplasty and stenting.

  3. The Integrity bare-metal stent made by continuous sinusoid technology.

    PubMed

    Turco, Mark A

    2011-05-01

    The Integrity Coronary Stent System (Medtronic Vascular, CA, USA) is a low-profile, open-cell, cobalt-chromium-alloy advanced bare-metal iteration of the well-known Driver/Micro-Driver Coronary Stent System (Medtronic Vascular). The Integrity stent is made with a process called continuous sinusoid technology. This process allows stent construction via wrapping a single thin strand of wire around a mandrel in a sinusoid configuration, with laser fusion of adjacent crowns. The wire-forming process and fusion pattern provide the stent with a continuous preferential bending plane, intended to allow easier access to, and smoother tracking within, distal and tortuous vessels while radial strength is maintained. Continuous sinusoid technology represents innovation in the design of stent platforms and will provide a future stent platform for newer technology, including drug-eluting stent platforms, drug-filled stents and core wire stents.

  4. Metallic ureteral stents in malignant ureteral obstruction: short-term results and radiological features predicting stent failure in patients with non-urological malignancies.

    PubMed

    Chow, Po-Ming; Hsu, Jui-Shan; Wang, Shuo-Meng; Yu, Hong-Jheng; Pu, Yeong-Shiau; Liu, Kao-Lang

    2014-06-01

    To provide short-term result of the metallic ureteral stent in patients with malignant ureteral obstruction and identify radiological findings predicting stent failure. The records of all patients with non-urological malignant diseases who have received metallic ureteral stents from July 2009 to March 2012 for ureteral obstruction were reviewed. Stent failure was detected by clinical symptoms and imaging studies. Survival analysis was used to estimate patency rates and factors predicting stent failure. A total of 74 patients with 130 attempts of stent insertion were included. A total of 113 (86.9 %) stents were inserted successfully and 103 (91.2 %) achieved primary patency. After excluding cases without sufficient imaging data, 94 stents were included in the survival analysis. The median functional duration of the 94 stents was 6.2 months (range 3-476 days). Obstruction in abdominal ureter (p = 0.0279) and lymphatic metastasis around ureter (p = 0.0398) were risk factors for stent failure. The median functional durations of the stents for abdominal and pelvic obstructions were 4.5 months (range 3-263 days) and 6.5 months (range 4-476 days), respectively. The median durations of the stents with and without lymphatic metastasis were 5.3 months (range 4-398 days) and 7.8 months (range 31-476 days), respectively. Metallic ureteral stents are effective and safe in relieving ureteral obstructions resulting from non-urological malignancies, and abdominal ureteral obstruction and lymphatic metastasis around ureter were associated with shorter functional duration.

  5. Outcomes of Prosthetic Hemodialysis Grafts after Deployment of Bare Metal versus Covered Stents at the Venous Anastomosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Charles Y., E-mail: charles.kim@duke.edu; Tandberg, Daniel J.; Rosenberg, Michael D.

    2012-08-15

    Purpose: To compare postintervention patency rates after deployment of bare metal versus covered stents across the venous anastomosis of prosthetic arteriovenous (AV) grafts. Methods: Review of our procedural database over a 6 year period revealed 377 procedures involving stent deployment in an AV access circuit. After applying strict inclusion criteria, our study group consisted of 61 stent deployments in 58 patients (median age 58 years, 25 men, 33 women) across the venous anastomosis of an upper extremity AV graft circuit that had never been previously stented. Both patent and thrombosed AV access circuits were retrospectively analyzed. Within the bare metalmore » stent group, 20 of 32 AV grafts were thrombosed at initial presentation compared to 18 of 29 AV grafts in the covered stent group. Results: Thirty-two bare metal stents and 29 covered stents were deployed across the venous anastomosis. The 3, 6, and 12 months primary access patency rates for bare metal stents were not significantly different than for covered stents: 50, 41, and 22 % compared to 59, 52, and 29 %, respectively (p = 0.21). The secondary patency rates were also not significantly different: 78, 78, and 68 % for bare metal stents compared to 76, 69, and 61 % for covered stents, respectively (p = 0.85). However, covered stents demonstrated a higher primary stent patency rate than bare metal stents: 100, 85, and 70 % compared to 75, 67, and 49 % at 3, 6, and 12 months (p < 0.01). Conclusion: The primary and secondary access patency rates after deployment of bare metal versus covered stents at the venous anastomosis were not significantly different. However, bare metal stents developed in-stent stenoses significantly sooner.« less

  6. Thirty-Day Outcome of a Multicenter Registry Study of Stenting for Symptomatic Intracranial Artery Stenosis in China.

    PubMed

    Miao, Zhongrong; Zhang, Yong; Shuai, Jie; Jiang, Changchun; Zhu, Qiyi; Chen, Kangning; Liu, Li; Li, Baomin; Shi, Xiangqun; Gao, Lianbo; Liu, Yajie; Wang, Feng; Li, Yongli; Liu, Tieyan; Zheng, Hongbo; Wang, Yilong; Wang, Yongjun

    2015-10-01

    Although recent trials have suggested that stenting is worse than medical therapy for patients with severe symptomatic intracranial atherosclerotic stenosis, it is not clear whether this conclusion applies to a subset of patients with hypoperfusion symptoms. To justify for a new trial in China, we performed a multicenter prospective registry study to evaluate the safety and efficacy of endovascular stenting within 30 days for patients with severe symptomatic intracranial atherosclerotic stenosis. Patients with symptomatic intracranial atherosclerotic stenosis caused by 70% to 99% stenosis combined with poor collaterals were enrolled. The patients were treated either with balloon-mounted stent or with balloon predilation plus self-expanding stent as determined by the operators following a guideline. The primary outcome within 30 days is stroke, transient ischemic attack, and death after stenting. The secondary outcome is successful revascularization. The baseline characteristics and outcomes of the 2 treatment groups were compared. From September 2013 to January 2015, among 354 consecutive patients, 300 patients (aged 58.3±9.78 years) were recruited, including 159 patients treated with balloon-mounted stent and 141 patients with balloon plus self-expanding stent. The 30-day rate of stroke, transient ischemic attack, and death was 4.3%. Successful revascularization was 97.3%. Patients treated with balloon-mounted stent were older, less likely to have middle cerebral artery lesions, more likely to have vertebral artery lesions, more likely to have Mori A lesions, less likely to have Mori C lesions, and likely to have lower degree of residual stenosis than patients treated with balloon plus self-expanding stent. The short-term safety and efficacy of endovascular stenting for patients with severe symptomatic intracranial atherosclerotic stenosis in China is acceptable. Balloon-mounted stent may have lower degree of residual stenosis than self-expanding stent. URL: http

  7. Malignant Ureteral Obstruction: Functional Duration of Metallic versus Polymeric Ureteral Stents

    PubMed Central

    Chow, Po-Ming; Chiang, I-Ni; Chen, Chia-Yen; Huang, Kuo-How; Hsu, Jui-Shan; Wang, Shuo-Meng; Lee, Yuan-Ju; Yu, Hong-Jeng; Pu, Yeong-Shiau; Huang, Chao-Yuan

    2015-01-01

    Background Ureteral obstruction caused by extrinsic compression is often associated with intra-abdominal cancers. Internal drainage with ureteral stents is typically the first-line therapy to relieve such obstructions. Novel designs of ureteral stents made of different materials have been invented to achieve better drainage. In this study, we described the functional outcomes of a Resonance metallic ureteral stent (Cook Medical, Bloomington, Indiana, USA) in patients with malignant ureteral obstruction and compare the functional duration of Resonance stents with regular polymeric stents in the same cohort. Methods Cancer patients who received polymeric stents and subsequent Resonance stents for ureteral obstruction between July 2009 and November 2012 were included in a chart review. Stent failure was detected by clinical symptoms, imaging studies, and renal function tests. The functional durations of each stent were calculated, and possible factors affecting stent patency were investigated. Results A total of 50 stents were successfully inserted into 50 ureteral units in 42 patients with malignant ureteral obstruction. There were 7 antegrade stents and 43 retrograde stents. There were no major complications. Stent-related symptoms were similar in both kinds of stents. After polymeric stents were replaced with Resonance metallic stents, hydronephrosis subsided or remained stable in 90% (45/50) of the ureteral units. Serum creatinine decreased or remained stable in 90% (38/42) of these patients. The Resonance stent exhibited a mean increase in functional duration of 4 months compared with the polymeric stents (p<0.0001), and 50% (25/50) of the Resonance stents exhibited a significant increase in functional duration (more than 3 months). Pre-operative serum creatinine < 2 was associated with a substantial increase in stent duration. Conclusions Resonance stents are effective and safe in relieving malignant ureteral obstructions after polymeric stents failure

  8. Outcomes of endovascular reconstruction of the inferior vena cava with self-expanding nitinol stents.

    PubMed

    Sebastian, Tim; Dopheide, Jörn F; Engelberger, Rolf P; Spirk, David; Kucher, Nils

    2018-05-01

    Occlusion of the inferior vena cava (IVC) often causes venous claudication, leg swelling, or skin changes. We hypothesized that the outcome of nitinol stents for endovascular reconstruction of the IVC is similar to the outcome reported for steel alloy stents. From the prospective Bern Venous Stent Registry, we investigated technical success, patency rates, and clinical outcome in consecutive patients with endovascular IVC reconstruction. During routine follow-up visits, stent patency was assessed by duplex ultrasound. Clinical outcomes were evaluated using the Bozkaya score, Villalta score, and revised Venous Clinical Severity Score. Of the 62 patients (mean age, 46 ± 18 years), 33 (53%) patients were treated for the post-thrombotic syndrome, 17 (27%) for acute thrombosis, and 12 (19%) for nonthrombotic IVC occlusion. Technical success was achieved in 61 (98%) patients, with a mean of 4.5 ± 1.9 stents (iliac kissing stents in 84%). During follow-up (mean, 21 months), 22 (36%) underwent endovascular reintervention for symptomatic stent stenosis (13 [21%] with complete stent occlusion). Primary, primary assisted, and secondary patency rates at 24 months were 57% (95% confidence interval [CI], 50%-73%), 76% (95% CI, 65%-86%), and 87% (95% CI, 80%-95%), respectively. None developed new ulcers, and all eight patients with venous ulcers at baseline had complete healing. Twenty-nine (48%) patients showed significant clinical improvement, and another 26 (43%) were free from any symptoms or signs of venous hypertension. Patients with post-thrombotic venographic changes of the femoral veins at baseline or a history of thrombosis were more likely to lose primary patency compared with patients with normal leg inflow veins and no history of thrombosis (19 [48%] vs 3 [16%]; P = .02). The clinical outcome of endovascular reconstruction of the IVC with nitinol stents was favorable. However, approximately one-third of the patients required reintervention to maintain stent

  9. Endoscopic Biliary Stenting Versus Percutaneous Transhepatic Biliary Stenting in Advanced Malignant Biliary Obstruction: Cost-effectiveness Analysis.

    PubMed

    Sun, Xin Rong; Tang, Cheng Wu; Lu, Wen Ming; Xu, Yong Qiang; Feng, Wen Ming; Bao, Yin; Zheng, Yin Yuan

    2014-05-01

    This study aims to compare the clinical outcomes and costs between endoscopic biliary stenting (EBS) and percutaneous transhepatic biliary stenting (PTBS). We randomly assigned 112 patients with unresectable malignant biliary obstruction 2006 and 2011 to receive EBS or PTBS with self-expandable metal stent (SEMS) as palliative treatment. PTBS was successfully performed in 55 patients who formed the PTBS group (failed in 2 patients). EBS was successfully performed in 52 patients who formed the EBS group (failed in 3 patients). The effectiveness of biliary drainage, hospital stay, complications, cost, survival time and mortality were compared. Patients in PTBS group had shorter hospital stay and lower initial and overall expense than the BBS group (P < 0.05). There was no significant difference in effectiveness of biliary drainage (P = 0.9357) or survival time between two groups (P = 0.6733). Early complications occurred in PTBS group was significantly lower than in EBS group (3/55 vs 11/52, P = 0.0343). Late complications in the EBS group did not differ significantly from PTBS group (7/55 vs 9/52, P = 0.6922). The survival curves in the two groups showed no significant difference (P = 0.5294). Conclusions: 3.

  10. [Treatment of a postoperative rectal stenosis with a self-expanding biodegradable polydioxanone stent].

    PubMed

    Dederichs, F; Knüdeler, S; Nolte, W; Iesalnieks, I

    2013-05-01

    Rectal stricture is a serious although infrequent complication of transanal endoscopic microsurgery (TEM). In some cases, these strictures may be refractory to treatment by endoscopic balloon dilatation. Biodegradable stents might improve the outcome by providing an extended period of dilatation. Moreover, these stents can remain in place without the need to remove them. In the presented case, a biodegradable polidioxanone stent originally developed to treat benign oesophageal stenoses was used to treat a patient suffering from rectal stricture following a TEM. © Georg Thieme Verlag KG Stuttgart · New York.

  11. Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis

    PubMed Central

    Sabaté, Manel; Kaiser, Christoph; Brugaletta, Salvatore; de la Torre Hernandez, Jose Maria; Galatius, Soeren; Cequier, Angel; Eberli, Franz; de Belder, Adam; Serruys, Patrick W; Ferrante, Giuseppe

    2014-01-01

    Objectives To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Design Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Data sources and study selection Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. Primary outcomes The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. Results The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001), and target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001) at a median follow-up of 720 days. There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14). Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual

  12. Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis.

    PubMed

    Valgimigli, Marco; Sabaté, Manel; Kaiser, Christoph; Brugaletta, Salvatore; de la Torre Hernandez, Jose Maria; Galatius, Soeren; Cequier, Angel; Eberli, Franz; de Belder, Adam; Serruys, Patrick W; Ferrante, Giuseppe

    2014-11-04

    To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001), and target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001) at a median follow-up of 720 days. There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14). Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual antiplatelets. This meta-analysis offers evidence that compared with bare metal

  13. Stent patency in patients with distal malignant biliary obstruction receiving chemo(radio)therapy

    PubMed Central

    Haal, Sylke; van Hooft, Jeanin E.; Rauws, Erik A. J.; Fockens, Paul; Voermans, Rogier P.

    2017-01-01

    Background and study aims  Recent literature suggests that chemo(radio)therapy might reduce the patency of plastic stents in patients with malignant biliary obstruction. Whether this might also be valid for other types of stents is unknown. The aim of this study was to determine the influence of chemo(radio)therapy on the patency of fully-covered self-expandable metal stents (FCSEMSs) and plastic stents. Patients and methods  We retrospectively reviewed the electronic medical records of patients with distal malignant biliary obstruction who underwent biliary stent placement between April 2001 and July 2015. Primary outcome was duration of stent patency. Secondary outcome was stent patency at 3 and 6 months. We used Kaplan–Meier survival analyses to compare stent patency rates between patients who received chemo(radio)therapy and patients who did not. Results  A total of 291 biliary stents (151 metal and 140 plastic) were identified. The median cumulative stent patency of FCSEMSs did not differ between patients receiving chemo(radio)therapy (n = 51) and those (n = 100) who did not ( P  = 0.70, log-rank test). The estimated cumulative stent patency of plastic stents was also comparable in 99 patients without and 41 patients with chemo(radio)therapy ( P  = 0.73, log-rank test). At 3 and 6 months, FCSEMS patency rates were 87 % and 83 % in patients without chemo(radio)therapy and 96 % and 83 % in patients with therapy, respectively. Plastic patency rates were 69 % and 55 % in patients without and 85 % and 39 % in patients with therapy, respectively. After 1 year, 78 % of the FCSEMSs were still patent in patients without chemo(radio)therapy and 69 % of the FCSEMSs were still patent in patients with therapy. Conclusion  Our data indicate that chemo(radio)therapy does not reduce the patency of biliary fully-covered metal and plastic stents. PMID:29090242

  14. Stent patency in patients with distal malignant biliary obstruction receiving chemo(radio)therapy.

    PubMed

    Haal, Sylke; van Hooft, Jeanin E; Rauws, Erik A J; Fockens, Paul; Voermans, Rogier P

    2017-11-01

     Recent literature suggests that chemo(radio)therapy might reduce the patency of plastic stents in patients with malignant biliary obstruction. Whether this might also be valid for other types of stents is unknown. The aim of this study was to determine the influence of chemo(radio)therapy on the patency of fully-covered self-expandable metal stents (FCSEMSs) and plastic stents.  We retrospectively reviewed the electronic medical records of patients with distal malignant biliary obstruction who underwent biliary stent placement between April 2001 and July 2015. Primary outcome was duration of stent patency. Secondary outcome was stent patency at 3 and 6 months. We used Kaplan-Meier survival analyses to compare stent patency rates between patients who received chemo(radio)therapy and patients who did not.  A total of 291 biliary stents (151 metal and 140 plastic) were identified. The median cumulative stent patency of FCSEMSs did not differ between patients receiving chemo(radio)therapy (n = 51) and those (n = 100) who did not ( P  = 0.70, log-rank test). The estimated cumulative stent patency of plastic stents was also comparable in 99 patients without and 41 patients with chemo(radio)therapy ( P  = 0.73, log-rank test). At 3 and 6 months, FCSEMS patency rates were 87 % and 83 % in patients without chemo(radio)therapy and 96 % and 83 % in patients with therapy, respectively. Plastic patency rates were 69 % and 55 % in patients without and 85 % and 39 % in patients with therapy, respectively. After 1 year, 78 % of the FCSEMSs were still patent in patients without chemo(radio)therapy and 69 % of the FCSEMSs were still patent in patients with therapy.  Our data indicate that chemo(radio)therapy does not reduce the patency of biliary fully-covered metal and plastic stents.

  15. Drug-eluting stents versus bare-metal stents for off-label indications: a propensity score-matched outcome study.

    PubMed

    Austin, David; Oldroyd, Keith G; McConnachie, Alex; Slack, Rachel; Eteiba, Hany; Flapan, Andrew D; Jennings, Kevin P; Northcote, Robin J; Pell, Alastair C H; Starkey, Ian R; Pell, Jill P

    2008-08-01

    The US Food and Drug Administration recently concluded that data on off-label drug-eluting stent (DES) safety are limited. However, in actual clinical practice, DES are often used for off-label indications, and observational studies demonstrate that complications are higher when compared with on-label use. We aimed to determine whether clinical outcomes differ after DES and bare-metal stent implantation in a patient cohort defined by DES off-label indications. We used the national revascularization registry in Scotland to identify patients who underwent coronary stenting for an off-label indication between January 2003 and September 2005. Individual-level linkage to comprehensive national admission and death databases was used to ascertain the end points of death, myocardial infarction, and target-vessel revascularization. We calculated propensity scores on the basis of clinical, demographic, and angiographic variables and matched DES to bare-metal stents on a 1:1 basis. The final study population consisted of 1642 patients, well matched for important covariables at baseline. Event-free survival was calculated over 24 months with the Kaplan-Meier method. All-cause death was more common after bare-metal stent implantation during follow-up (7.7% versus 6.6%; hazard ratio 0.63; 95% confidence interval, 0.40 to 0.99; P=0.04). No difference in the rates of myocardial infarction were noted (7.3% versus 7.5%; hazard ratio 1.02; 95% confidence interval, 0.69 to 1.54; P=0.92). Target-vessel revascularization was reduced in patients treated with DES (13.9% versus 10.7%; hazard ratio 0.67; 95% confidence interval, 0.49 to 0.93; P=0.02). At 24 months, patients treated with DES for off-label indications had lower rates of death and target-vessel revascularization and similar rates of myocardial infarction, as compared with patients treated with bare-metal stents.

  16. Temporary placement of stent grafts in postsurgical benign biliary strictures: a single center experience.

    PubMed

    Vellody, Ranjith; Willatt, Jonathon M; Arabi, Mohammad; Cwikiel, Wojciech B

    2011-01-01

    To evaluate the effect of temporary stent graft placement in the treatment of benign anastomotic biliary strictures. Nine patients, five women and four men, 22-64 years old (mean, 47.5 years), with chronic benign biliary anastomotic strictures, refractory to repeated balloon dilations, were treated by prolonged, temporary placement of stent-grafts. Four patients had strictures following a liver transplantation; three of them in bilio-enteric anastomoses and one in a choledocho-choledochostomy. Four of the other five patients had strictures at bilio-enteric anastomoses, which developed after complications following laparoscopic cholecystectomies and in one after a Whipple procedure for duodenal carcinoma. In eight patients, balloon-expandable stent-grafts were placed and one patient was treated by insertion of a self-expanding stent-graft. In the transplant group, treatment of patients with bilio-enteric anastomoses was unsuccessful (mean stent duration, 30 days). The patient treated for stenosis in the choledocho-choledochostomy responded well to consecutive self-expanding stent-graft placement (total placement duration, 112 days). All patients with bilio-enteric anastomoses in the non-transplant group were treated successfully with stent-grafts (mean placement duration, 37 days). Treatment of benign biliary strictures with temporary placement of stent-grafts has a positive effect, but is less successful in patients with strictures developed following a liver transplant.

  17. Bare Metal Stenting for Endovascular Exclusion of Aortic Arch Thrombi

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mahnken, Andreas H., E-mail: mahnken@med.uni-marburg.de; Hoffman, Andras; Autschbach, Ruediger

    BackgroundAortic thrombi in the ascending aorta or aortic arch are rare but are associated with a relevant risk of major stroke or distal embolization. Although stent grafting is commonly used as a treatment option in the descending aorta, only a few case reports discuss stenting of the aortic arch for the treatment of a thrombus. The use of bare metal stents in this setting has not yet been described.MethodsWe report two cases of ascending and aortic arch thrombus that were treated by covering the thrombus with an uncovered stent. Both procedures were performed under local anesthesia via a femoral approach.more » A femoral cutdown was used in one case, and a total percutaneous insertion was possible in the second case.ResultsBoth procedures were successfully performed without any periprocedural complications. Postoperative recovery was uneventful. In both cases, no late complications or recurrent embolization occurred at midterm follow-up, and control CT angiography at 1 respectively 10 months revealed no stent migration, freely perfused supra-aortic branches, and no thrombus recurrence.ConclusionTreating symptomatic thrombi in the ascending aorta or aortic arch with a bare metal stent is feasible. This technique could constitute a minimally invasive alternative to a surgical intervention or complex endovascular therapy with fenestrated or branched stent grafts.« less

  18. Endoscopic Management of Post-Liver Transplantation Biliary Strictures With the Use of Fully Covered Metallic Stents.

    PubMed

    Jiménez-Pérez, M; Melgar Simón, J M; Durán Campos, A; González Grande, R; Rodrigo López, J M; Manteca González, R

    2016-09-01

    The aim of this work was to evaluate the safety and efficacy of a fully covered self-expandable metal stent (FCSEMS) in the treatment of post-liver transplantation biliary strictures. From October 2009 to October 2014, 44 patients with post-liver transplantation biliary stenosis were treated with the use of endoscopic retrograde cholangiography and placement of FCSEMS after informed consent. The FCSEMS was scheduled to remain in situ for 3-6 months. Patients were followed at regular intervals to evaluate for symptoms and liver function tests. Technical success, complications, and patient outcome were analyzed. All of the strictures were anastomotic, 52% having occurred within the 1st year following the transplantation. Placement of the FCSEMS was possible on the 1st attempt in 54% of patients. Stricture resolution at the time of stent removal was seen in 100% of the cases. During an average follow-up of 27.83 ± 18.3 months after stent removal, stenosis recurred in 9 out of 41 patients (21.9%). The average time of recurrence was 11.78 ± 13.3 months. In all of these cases, the recurrence was resolved by means of placement of another FCSEMS. In 4 cases, the recurrence was associated with a migration of the prosthesis, partial in 2 cases and total in 2 cases. Stent migration occurred in a total of 17 of the 41 patients (41.4%), in 13 of the 32 (40.6%) who had no recurrence of stenosis and in 4 of the 9 (44.4%) of those who experienced recurrence. The average numbers of endoscopic retrograde cholangiography studies required per patient were 2.8 in those with no recurrence and 3.3 in those with recurrence. No death was associated with the process. FCSEMS is a safe effective alternative to plastic stents in the treatment of post-transplantation biliary strictures, resulting in a lower risk of complications and better patient acceptance. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Management of colon stents based on Bernoulli's principle.

    PubMed

    Uno, Yoshiharu

    2017-03-01

    The colonic self-expanding metal stent (SEMS) has been widely used for "bridge to surgery" and palliative therapy. However, if the spread of SEMS is insufficient, not only can a decompression effect not be obtained but also perforation and obstructive colitis can occur. The mechanism of occurrence of obstructive colitis and perforation was investigated by flow dynamics. Bernoulli's principle was applied, assuming that the cause of inflammation and perforation represented the pressure difference in the proximal lumen and stent. The variables considered were proximal lumen diameter, stent lumen diameter, flow rate into the proximal lumen, and fluid density. To model the right colon, the proximal lumen diameter was set at 50 mm. To model the left-side colon, the proximal lumen diameter was set at 30 mm. For both the right colon model and the left-side colon model, the difference in pressure between the proximal lumen and the stent was less than 20 mmHg, when the diameter of the stent lumen was 14 mm or more. Both the right colon model and the left-side colon model were 30 mmHg or more at 200 mL s -1 when the stent lumen was 10 mm or less. Even with an inflow rate of 90-110 mL s -1 , the pressure was 140 mmHg when the stent lumen diameter was 5 mm. In theory, in order to maintain the effectiveness of SEMS, it is necessary to keep the diameter of the stent lumen at 14 mm or more.

  20. [Assessment of the course of ischemic heart disease after placement of stents with drug covering and uncovered metal stents: data of 3 years follow-up].

    PubMed

    Buza, V V; Karpov, Iu A; Samko, A N; Deev, A D; Lopukhova, V V; Levitskiĭ, I V; Sozykin, A V

    2009-01-01

    The placement of sirolimus-eluting stents decreases the frequency of repeat revascularization procedures in patients undergoing percutaneous coronary intervention (PCI) in randomized clinical trials. However, there is uncertainty about the effectiveness of sirolimus-eluting stents, and increasing concern about their safety in routine clinical practice. From the prof. Samko PCI laboratory in Moscow, Russia, we identified 426 patients, who received either bare-metal stents alone or sirolimus-eluting stents alone during an index PCI procedure between March 1, 2002, and September 31, 2004.The primary outcomes of the study were the rates of target-lesion revascularization, myocardial infarction, death, late stent thrombosis. The 3-year rate of target-lesion revascularization was significantly lower among patients who received sirolimus-eluting stents than among those who received bare-metal stents (3.1% vs. 19 %, p=0.001). The 3-year mortality rate was not different between the bare-metal stent group and the sirolimus eluting stent group (5.9% vs. 7.2%, p=0.68), the 3-year rate of all ARC late stent thrombosis was similar in the two groups (5.9% and 7.2%, respectively; p=0.95). Sirolimus-eluting stents are effective in reducing the need for target-vessel revascularization without significantly increased rates of death, late stent thrombosis, myocardial infarction.

  1. Spectrum of histopathological changes encountered in stented colorectal carcinomas.

    PubMed

    Fryer, Eve; Gorissen, Kim J; Wang, Lai Mun; Guy, Richard; Chetty, Runjan

    2015-03-01

    Self-expanding metallic stents (SEMS) are increasingly being used in obstructing colorectal cancer (CRC) as a 'bridge to surgery', allowing conversion of potentially high-risk emergency resections to elective procedures. Stenting may cause a wide array of histological changes. We present the largest series to date of stented CRC, performed and reported at a single institution. Stented CRC specimens received in January 2006 to December 2011 were identified from our pathology database. Slides for each case were independently reviewed by two pathologists, and a consensus was reached. A total of 72 CRCs were identified, 15 at or proximal to the splenic flexure, and 57 left-sided. Thirty-six were stage pT3 and 36 were stage pT4. Perforation was observed in 14 cases. The effects of stenting on the tumour included tumour necrosis (100%) and flat ulceration (77.8%). The spectrum of changes in the background bowel included mimics of inflammatory bowel disease, tumour regression post-neoadjuvant therapy, and ischaemia. Given the inclusion of stenting of CRC as a bridge to surgery in the current NICE guidelines, we expect to see increasing numbers of such cases. In our study, a range of changes were encountered that mimic other bowel diseases, from simple fissuring to chronic inflammatory bowel disease and neoadjuvant regression change. © 2014 John Wiley & Sons Ltd.

  2. Comparison of direct site endovascular repair utilizing expandable polytetrafluoroethylene stent grafts versus standard vascular shunts in a porcine (Sus scrofa) model.

    PubMed

    Davidson, Anders J; Neff, Lucas P; Grayson, J Kevin; Clement, Nathan F; DeSoucy, Erik S; Simon Logan, Meryl A; Abbot, Christopher M; Sampson, James B; Williams, Timothy K

    2017-09-01

    The small diameter of temporary vascular shunts for vascular trauma management may restrict flow and result in ischemia or early thrombosis. We have previously reported a clinical experience with direct, open surgical reconstruction using expandable polytetrafluoroethylene stent grafts to create a "sutureless" anastomosis as an alternative to standard temporary vascular shunts. We sought to characterize patency and flow characteristics of these grafts compared with standard shunts in a survival model of porcine vascular injury. Twelve Yorkshire-cross swine received a 2-cm-long near-circumferential defect in the bilateral iliac arteries. A 14 Fr Argyle shunt was inserted into one randomly assigned artery, with a self-expanding expandable polytetrafluoroethylene stent deployed in the other. At 72 hours, conduit patency was evaluated by angiography. Arterial flow measurements were obtained at baseline, immediately after intervention, and after 72 hours via direct measurement with perivascular flow meters. Blood pressure proximal and distal to the conduits and arterial samples for histopathology were obtained during the terminal procedure. Angiography revealed no difference in patency at 72 hours (p = 1.0). While there was no difference in baseline arterial flow between arteries (p = 0.63), the stent grafts demonstrated significantly improved blood flow compared with shunts both immediately after intervention (390 ± 36 mL/min vs. 265 ± 25 mL/min, p = 0.002) and at 72 hours (261 ± 29 mL/min vs. 170 ± 36 mL/min, p = 0.005). The pressure gradient across the shunts was greater than that of the stent grafts (11.5 mm Hg [interquartile range, 3-19 mm Hg] vs. 3 mm Hg [interquartile range, 3-5 mm Hg], p = 0.013). The speed of deployment was similar between the two devices. Open "sutureless" direct site repair using commercially available stent grafts to treat vascular injury is a technically feasible strategy for damage control management of peripheral vascular injury and

  3. Use of the Viatorr Expanded Polytetrafluoroethylene-Covered Stent-Graft for Transjugular Intrahepatic Portosystemic Shunt Creation in Children: Initial Clinical Experience

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mermuys, Koen; Maleux, Geert, E-mail: geert.maleux@uzleuven.be; Heye, Sam

    2008-07-15

    Four children, three boys and one girl, with a median age of 9 years 8 months, underwent transjugular intrahepatic portosystemic shunt creation with an expanded polytetrafluoroethylene (e-PTFE)-covered nitinol stent. The stent-graft was successfully placed in all four patients without any complication. Clinical and biochemical improvement was noted in all four patients during follow-up. Radiological follow-up with use of duplex ultrasound showed a recurrent stenosis of the shunt 180 days after stent-graft implantation in one patient. This was treated with placement of an additional stent-graft, re-expanding completely the recurrent stenosis. In the other three patients, the stent-graft remained fully patent untilmore » the end of the study or until orthotopic liver transplantation. These preliminary results suggest that use of the Viatorr ePTFE-covered stent-graft in children is safe and feasible, with potentially the same high patency rate and improved clinical outcome as reported in adult patients.« less

  4. Comparison of partially covered nitinol stents with partially covered stainless stents as a historical control in a multicenter study of distal malignant biliary obstruction: the WATCH study.

    PubMed

    Isayama, Hiroyuki; Mukai, Tsuyoshi; Itoi, Takao; Maetani, Iruru; Nakai, Yousuke; Kawakami, Hiroshi; Yasuda, Ichiro; Maguchi, Hiroyuki; Ryozawa, Shomei; Hanada, Keiji; Hasebe, Osamu; Ito, Kei; Kawamoto, Hirofumi; Mochizuki, Hitoshi; Igarashi, Yoshinori; Irisawa, Atsushi; Sasaki, Tamito; Togawa, Osamu; Hara, Taro; Kamada, Hideki; Toda, Nobuo; Kogure, Hirofumi

    2012-07-01

    Covered self-expandable metal stents (CSEMSs) were developed to prevent tumor ingrowth, but stent migration is one of the problems with CSEMSs. To evaluate a new, commercially available CSEMS with flared ends and low axial force compared with a commercially available CSEMS without the anti-migration system and high axial force. Multicenter, prospective study with a historical cohort. Twenty Japanese referral centers. This study involved patients with unresectable distal malignant biliary obstruction. Placement of a new, commercially available, partially covered SEMS. Recurrent biliary obstruction rate, time to recurrent biliary obstruction, stent-related complications, survival. Between April 2009 and March 2010, 141 patients underwent partially covered nitinol stent placement, and between May 2001 and January 2007, 138 patients underwent placement of partially covered stainless stents as a historical control. The silicone cover of the partially covered nitinol stents prevented tumor ingrowth. There were no significant differences in survival (229 vs 219 days; P = .250) or the rate of recurrent biliary obstruction (33% vs 38%; P = .385) between partially covered nitinol stents and partially covered stainless stents. Stent migration was less frequent (8% vs 17%; P = .019), and time to recurrent biliary obstruction was significantly longer (373 vs 285 days; P = .007) with partially covered nitinol stents. Stent removal was successful in 26 of 27 patients (96%). Nonrandomized, controlled trial. Partially covered nitinol stents with an anti-migration system and less axial force demonstrated longer time to recurrent biliary obstruction with no tumor ingrowth and less stent migration. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  5. Use of a retrievable metallic stent internally coated with silicone to treat airway obstruction.

    PubMed

    Kim, Jin Hyoung; Shin, Ji Hoon; Song, Ho-Young; Lee, Se Chul; Kim, Kyung Rae; Park, Jung-Hoon

    2008-08-01

    The authors hypothesized that internally covered stents can reduce the rates of stent migration or mucous retention. The authors performed this study to report their experience with use of a retrievable metallic stent internally coated with silicone in patients with benign or malignant central airway obstructions. From 2004 to 2007, the authors performed fluoroscopically guided placement of a retrievable metallic stent internally coated with silicone in 26 consecutive patients with benign (n = 5) and malignant (n = 21) central airway obstructions. Stents were woven from a single thread of a 0.2-mm-diameter nitinol wire in a tubular configuration and internally covered with silicone membrane. Stent placement was technically and clinically successful in 93% (25/26) and 85% (22/26) of the patients, respectively. There were eight complications (31%) after stent placement, including tumor overgrowth (n = 2), stent migration (n = 1), symptomatic granulation tissue formation (n = 1), severe pain (n = 1), improper stent location (n = 1), symptomatic sputum retention (n = 1) and esophagobronchial fistula (n = 1). Because of complications, five stents were removed with a retrieval hook under fluoroscopic guidance without difficulty. The median survival period and stent patency were 150.0 days +/- 91.4 and 143.0 days +/- 26.7, respectively. The use of a retrievable metallic stent internally coated with silicone is a safe and effective method for relieving dyspnea, with adequate stent patency in patients with benign or malignant central airway obstructions. This stent design seems to be less prone to migration or mucous retention.

  6. Side-by-side placement of bilateral endoscopic metal stents for the treatment of postoperative biliary stricture.

    PubMed

    Kaino, Seiji; Sen-Yo, Manabu; Shinoda, Shuhei; Kawano, Michitaka; Harima, Hirofumi; Suenaga, Shigeyuki; Sakaida, Isao

    2017-02-01

    Postoperative biliary strictures are usually complications of cholecystectomy. Endoscopic plastic stent prosthesis is generally undertaken for treating benign biliary strictures. Recently, fully covered metal stents have been shown to be effective for treating benign distal biliary strictures. We present the case of a 53-year-old woman with liver injury in which imaging studies showed a common hepatic duct stricture. Endoscopic retrograde cholangiopancreatography also confirmed the presence of a common hepatic duct stricture. Temporally fully covered metal stents with dilated diameters of 6 mm were placed in a side-by-side fashion in the left and right hepatic ducts, respectively. We removed the stents 2 months after their placement. Subsequent cholangiography revealed an improvement in the biliary strictures. Although we were apprehensive about the fully covered metal stents obstructing the biliary side branches, we noted that careful placement of the bilateral metal stents did not cause any complications. Side-by-side deployment of bilateral endoscopic fully covered metal stents can be one of the safe and effective therapies for postoperative biliary stricture.

  7. Metallic stents in the management of ureteric strictures

    PubMed Central

    Kulkarni, Ravi

    2014-01-01

    Management of ureteric strictures is a challenging task. Subtle presentation, silent progression and complex aetiology may delay diagnosis. A wide range of available treatment options combined with the lack of adequate randomised trials has led to the introduction of personal bias in the management of this difficult group of patients. Metallic ureteric stents offer an alternative to the conventional treatment modalities. A review of the currently available metallic stents and their role in the long-term management of ureteric strictures is presented. Materials used in the manufacture of indwelling urological devices are evolving all the time. Improved endo-urological techniques combined with new devices made from better compounds will continue to improve patient experience. PMID:24497686

  8. Technological Advances in Stent Therapies: a Year in Review.

    PubMed

    Raffoul, Jad; Nasir, Ammar; Klein, Andrew J P

    2018-04-07

    Stent technology has rapidly evolved since the first stainless steel bare metal stents with substantial developments in scaffolding, polymer, drug choice, drug delivery, and elution mechanisms. Most recently, there has been the evolution of bioabsorbable vascular scaffolds, potentially eliminating the need for long-term foreign object retention. These rapid developments have led to an ever-expanding selection of new stents, making the choice of which to use in which patient challenging. Operators must balance potential short- and long-term clinical ramifications, namely stent thrombosis, in-stent restenosis, target lesion revascularization, and target lesion failure. In this review, we hope to provide insight for interventional cardiologists on the details of stent technology and how this impacts outcomes, stent selection, and duration of dual-antiplatelet therapy duration post drug-eluting stent implantation.

  9. Transjugular Intrahepatic Portosystemic Shunt Flow Reduction with Adjustable Polytetrafluoroethylene-Covered Balloon-Expandable Stents Using the “Sheath Control” Technique

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blue, Robert C., E-mail: Robert.c.blue@gmail.com; Lo, Grace C.; Kim, Edward

    PurposeA complication of transjugular intrahepatic portosystemic shunts (TIPS) placement is refractory portosystemic encephalopathy (PSE) often requiring TIPS reduction. We report the results of a “sheath control technique” utilizing constraining sheaths during deployment of polytetrafluoroethylene (PTFE)-covered balloon-expandable stents, minimizing stent migration, and providing additional procedural control.MethodsTIPS reduction was performed in 10 consecutive patients for PSE using Atrium iCast covered stents (Atrium Maquet Getinge Group, Germany). Within the indwelling TIPS stent, a 9 mm × 59 mm iCast stent was deployed with 2 cm exposed from the sheath’s distal end and the majority of the stent within the sheath to create the distal hourglass shape. During balloonmore » retraction, the stent was buttressed by the sheath. The proximal portion of the stent was angioplastied to complete the hourglass configuration, and the central portion of the stent was dilated to 5 mm. Demographics, pre- and post-procedure laboratory values, and outcomes were recorded.ResultsTen patients underwent TIPS reduction with 100 % technical success. There was no stent migration during stent deployment. All patients experienced initial improvement of encephalopathy. One patient ultimately required complete TIPS occlusion for refractory PSE, and another developed TIPS occlusion 36 days post-procedure. There was no significant trend toward change in patients’ MELD scores immediately post-procedure or at 30 days (p = 0.46, p = 0.47, respectively).ConclusionTIPS reduction using Atrium iCast PTFE balloon-expandable stents using the “sheath control technique” is safe and effective, and minimizes the risk of stent migration.« less

  10. Comparison of a New Polytetrafluoroethylene-Covered Metallic Stent to a Noncovered Stent in Canine Ureters

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chung, Hwan-Hoon, E-mail: chungmic@korea.ac.kr; Lee, Seung Hwa; Cho, Sung Bum

    The aim of this study was to determine the feasibility of using a newly designed polytetrafluoroethylene (PTFE)-covered metallic stent in the ureter by comparing its effectiveness with that of the noncovered stent in a canine model. We placed 14 stents in the ureters of seven mongrel dogs that weighed 30-40 kg each. The covered and noncovered stents were deployed in the right and left ureters, respectively, of six dogs. In the seventh dog, a covered stent and a double-J catheter were inserted in the right ureter, and a covered stent only was inserted in the left ureter. The first sixmore » dogs were sacrificed at 5, 10, and 15 weeks after deployment of the stents (two for each follow-up period), and the seventh dog was sacrificed at 30 weeks. There was no migration or poor expansion of any of the stents observed on plain radiography. On intravenous pyelogram and retrograde pyelogram, all of the covered stents at each follow-up period had patent lumens at the stented segments without hydronephrosis, and the passage of contrast material through it was well preserved. The noncovered stents in the dogs sacrificed at 5 and 10 weeks and one of the two dogs sacrificed at 15 weeks showed near-complete occlusion of the stent lumen due to ingrowth of the soft tissue, and severe hydronephrosis was also noted. The noncovered stent in the other dog sacrificed at 15 weeks showed the passage of contrast material without hydronephrosis, but the lumen of the stent was still nearly occluded by the soft tissue. There was no evidence of hydronephrosis or passage disturbance of the contrast material in both ureters of the dog sacrificed at 30 weeks. We conclude that the newly designed PTFE-covered stent effectively prevented the luminal occlusion caused by urothelial hyperplasia compared to the near-total occlusion of the noncovered stents, and no migration of the covered stents was noted.« less

  11. Hematopoietic Stem Cell Capture and Directional Differentiation into Vascular Endothelial Cells for Metal Stent-Coated Chitosan/Hyaluronic Acid Loading CD133 Antibody

    PubMed Central

    Zhang, Fan; Feng, Bo; Fan, Qingyu; Yang, Feng; Shang, Debin; Sui, Jinghan; Zhao, Hong

    2015-01-01

    A series of metal stents coated with chitosan/hyaluronic acid (CS/HA) loading antibodies by electrostatic self-assembled method were prepared, and the types of cells captured by antibodies and their differentiation in vascular endothelial cells (ECs) evaluated by molecular biology and scanning electron microscope. The results showed that CD133 stent can selectively capture hematopoietic stem cells (HSC),which directionally differentiate into vascular ECs in peripheral blood by (CS/HA) induction, and simultaneously inhibit migration and proliferation of immune cells and vascular smooth muscle cells (MCs). CD34 stent can capture HSC, hematopoietic progenitor cells that differentiate into vascular ECs and immune cells, promoting smooth MCs growth, leading to thrombosis, inflammation, and rejection. CD133 stent can be implanted into miniature pig heart coronary and can repair vascular damage by capturing own HSC, thus contributing to the rapid natural vascular repair, avoiding inflammation and rejection, thrombosis and restenosis. These studies demonstrated that CD133 stent of HSC capture will be an ideal coated metal stent providing a new therapeutic approach for cardiovascular and cerebrovascular disease. PMID:25404533

  12. Hematopoietic stem cell capture and directional differentiation into vascular endothelial cells for metal stent-coated chitosan/hyaluronic acid loading CD133 antibody.

    PubMed

    Zhang, Shixuan; Zhang, Fan; Feng, Bo; Fan, Qingyu; Yang, Feng; Shang, Debin; Sui, Jinghan; Zhao, Hong

    2015-03-01

    A series of metal stents coated with chitosan/hyaluronic acid (CS/HA) loading antibodies by electrostatic self-assembled method were prepared, and the types of cells captured by antibodies and their differentiation in vascular endothelial cells (ECs) evaluated by molecular biology and scanning electron microscope. The results showed that CD133 stent can selectively capture hematopoietic stem cells (HSC),which directionally differentiate into vascular ECs in peripheral blood by (CS/HA) induction, and simultaneously inhibit migration and proliferation of immune cells and vascular smooth muscle cells (MCs). CD34 stent can capture HSC, hematopoietic progenitor cells that differentiate into vascular ECs and immune cells, promoting smooth MCs growth, leading to thrombosis, inflammation, and rejection. CD133 stent can be implanted into miniature pig heart coronary and can repair vascular damage by capturing own HSC, thus contributing to the rapid natural vascular repair, avoiding inflammation and rejection, thrombosis and restenosis. These studies demonstrated that CD133 stent of HSC capture will be an ideal coated metal stent providing a new therapeutic approach for cardiovascular and cerebrovascular disease.

  13. Materials and Manufacturing Technologies Available for Production of a Pediatric Bioabsorbable Stent

    PubMed Central

    Alexy, Ryan D.; Levi, Daniel S.

    2013-01-01

    Transcatheter treatment of children with congenital heart disease such as coarctation of the aorta and pulmonary artery stenosis currently involves the use of metal stents. While these provide good short term results, there are long term complications with their use. Children outgrow metal stents, obligating them to future transcatheter dilations and eventual surgical removal. A bioabsorbable stent, or a stent that goes away with time, would solve this problem. Bioabsorbable stents are being developed for use in coronary arteries, however these are too small for use in pediatric congenital heart disease. A bioabsorbable stent for use in pediatric congenital heart disease needs to be low profile, expandable to a diameter 8 mm, provide sufficient radial strength, and absorb quickly enough to allow vessel growth. Development of absorbable coronary stents has led to a great understanding of the available production techniques and materials such as bioabsorbable polymers and biocorrodable metals. Children with congenital heart disease will hopefully soon benefit from the current generation of bioabsorbable and biocorrodable materials and devices. PMID:24089660

  14. The Influence of a Metal Stent on the Distribution of Thermal Energy during Irreversible Electroporation

    PubMed Central

    van den Bos, Willemien; Neal, Robert E.; van Lienden, Krijn P.; Besselink, Marc G. H.; van Gemert, Martin J. C.; van der Geld, Cees W. M.; Meijerink, Martijn R.; Klaessens, John H.; Verdaasdonk, Rudolf M.

    2016-01-01

    Purpose Irreversible electroporation (IRE) uses short duration, high-voltage electrical pulses to induce cell death via nanoscale defects resulting from altered transmembrane potential. The technique is gaining interest for ablations in unresectable pancreatic and hepatobiliary cancer. Metal stents are often used for palliative biliary drainage in these patients, but are currently seen as an absolute contraindication for IRE due to the perceived risk of direct heating of the metal and its surroundings. This study investigates the thermal and tissue viability changes due to a metal stent during IRE. Methods IRE was performed in a homogeneous tissue model (polyacrylamide gel), without and with a metal stent placed perpendicular and parallel to the electrodes, delivering 90 and 270 pulses (15–35 A, 90 μsec, 1.5 cm active tip exposure, 1.5 cm interelectrode distance, 1000–1500 V/cm, 90 pulses/min), and in-vivo in a porcine liver (4 ablations). Temperature changes were measured with an infrared thermal camera and with fiber-optic probes. Tissue viability after in-vivo IRE was investigated macroscopically using 5-triphenyltetrazolium chloride (TTC) vitality staining. Results In the gel, direct stent-heating was not observed. Contrarily, the presence of a stent between the electrodes caused a higher increase in median temperature near the electrodes (23.2 vs 13.3°C [90 pulses]; p = 0.021, and 33.1 vs 24.8°C [270 pulses]; p = 0.242). In-vivo, no temperature difference was observed for ablations with and without a stent. Tissue examination showed white coagulation 1mm around the electrodes only. A rim of vital tissue remained around the stent, whereas ablation without stent resulted in complete tissue avitality. Conclusion IRE in the vicinity of a metal stent does not cause notable direct heating of the metal, but results in higher temperatures around the electrodes and remnant viable tissue. Future studies should determine for which clinical indications IRE in the

  15. Supera self-expanding stents for endovascular treatment of femoropopliteal disease: a review of the clinical evidence

    PubMed Central

    Bishu, Kalkidan; Armstrong, Ehrin J

    2015-01-01

    Femoropopliteal lesions account for a significant proportion of endovascular interventions for peripheral artery disease in patients with disabling claudication or chronic limb ischemia. The femoropopliteal artery crosses two joint structures (hip and knee joints) and courses through the muscular adductor canal in the thigh, which places the artery at increased biomechanical stress. There is a critical need for stent platforms with a reduced risk of stent fracture while maintaining patency during long-term follow-up. The Supera peripheral stent system has a braided nickel–titanium alloy stent designed to withstand the unique stressors along the course of the femoropopliteal artery. This design may be associated with improved patency in association with reduced stent fracture rates on short- and medium-term follow-up. Further studies, including randomized controlled studies, comparing the Supera interwoven nickel–titanium alloy stent system with other stent platforms and angioplasty alone are needed. PMID:26203255

  16. Successful Kissing Balloon Expandable Stent Graft Treatment for a Right Common Carotid Pseudoaneurysm Caused by Tracheotomy.

    PubMed

    Agyei, Justice O; Alvarez, Cynthia; Iqbal, Azher; Fanous, Andrew A; Siddiqui, Adnan H

    2018-06-01

    A rare complication following tracheotomy is common carotid artery (CCA) pseudoaneurysm. Treatment modalities for CCA pseudoaneurysm include surgical repair and single-artery balloon-covered stent graft technique. We describe successful treatment of tracheotomy-related CCA pseudoaneurysm with the "kissing balloon" expandable stent graft technique. We successfully implemented the kissing balloon expandable stent graft technique for treatment of a large, narrow-necked, bilobed CCA pseudoaneurysm that arose owing to a tracheotomy complication. The pseudoaneurysm was detected while performing a diagnostic angiogram of the aortic arch and surrounding vessels. The stent was deployed while the 2 balloons were introduced in a kissing manner such that they faced one another to avoid occlusion of either branch of the innominate artery coming into contact; 1 balloon was inflated at the origin of the right subclavian artery, and the other was inflated at the right innominate artery simultaneously. The pseudoaneurysm was successfully contained; normal blood flow was restored in the CCA. The balloons were deflated and withdrawn. The patient remained neurologically intact after the procedure. The kissing balloon technique is a safe and effective alternative to surgical repair, as it prevents morbidities associated with the surgical procedure. Also, this technique decreases the risk of major side-branch occlusion associated with the single-artery balloon-covered stent graft technique. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. The use of cold sprayed alloys for metallic stents

    NASA Astrophysics Data System (ADS)

    AL-Mangour, Bandar

    With the invention of the coronary stent, which is a wire metal mesh tube designed to keep the arteries open in the treatment of heart diseases, promising clinical outcomes were generated. However, the long term successes of stents have been delayed by significant in-stent restenosis (blockages) and stent fracture. In this research work, it has been proposed to use Cold Gas Dynamic Spraying (CGDS) coating material as an alternative choice to manufacture metallic stent. In CGDS, fine particles are accelerated to a high velocity and undergo solid-state plastic deformation upon impact on the substrate, which leads to particle-particle bonding. The feature of CGDS distinct from other thermal spray techniques is that the processing gas temperature is below the melting point of the feedstock. Therefore, unwanted effects of high temperatures, such as oxidation, grain growth and thermal stresses, are absent. In response to the fact that the majority of stents are made from stainless steel (316L) or Co-Cr alloy (L605), this study specifically addresses the development and characterization of 316L and 316L mixed with L605 coatings produced by the CGDS process. Scanning electron microscopy and electron backscatter diffraction were used to investigate the microstructural changes of these coatings before and after annealing. The effect of gas type on the microstructure of 316L coatings and the role of post-heat treatment in the microstructure and properties are also studied. Of particular interest are grain refinement, heat treatment, mechanical properties and corrosion behavior of the cold sprayed material.

  18. Efficacy of Retrievable Metallic Stent with Fixation String for Benign Stricture after Upper Gastrointestinal Surgery.

    PubMed

    Kim, Jeong-Eun; Kim, Hyo-Cheol; Lee, Myungsu; Hur, Saebeom; Kim, Minuk; Lee, Sang Hwan; Cho, Soo Buem; Kim, Chan Sun; Han, Joon Koo

    2016-01-01

    To determine the efficacy of retrievable metallic stent with fixation string for benign anastomotic stricture after upper gastrointestinal (UGI) surgery. From June 2009 to May 2015, a total of 56 retrievable metallic stents with fixation string were placed under fluoroscopy guidance in 42 patients who were diagnosed with benign anastomotic stricture after UGI surgery. Clinical success was defined as achieving normal regular diet (NRD). The clinical success rate after the first stent placement was 57.1% (24/42). After repeated stent placement and/or balloon dilation, the clinical success rate was increased to 83.3% (35/42). Six (14.3%) patients required surgical revision to achieve NRD. One (2.4%) patient failed to achieve NRD. Stent migration occurred in 60.7% (34/56) of patients. Successful rate of removing the stent using fixation string and angiocatheter was 94.6% (53/56). Distal migration occurred in 12 stents. Of the 12 stents, 10 (83.3%) were successfully removed whereas 2 could not be removed. No complication occurred regarding distal migration. Using retrievable metallic stent with a fixation string is a feasible option for managing early benign anastomotic stricture after UGI surgery. It can reduce complications caused by distal migration of the stent.

  19. Efficacy of Retrievable Metallic Stent with Fixation String for Benign Stricture after Upper Gastrointestinal Surgery

    PubMed Central

    Kim, Jeong-Eun; Lee, Myungsu; Hur, Saebeom; Kim, Minuk; Lee, Sang Hwan; Cho, Soo Buem; Kim, Chan Sun; Han, Joon Koo

    2016-01-01

    Objective To determine the efficacy of retrievable metallic stent with fixation string for benign anastomotic stricture after upper gastrointestinal (UGI) surgery. Materials and Methods From June 2009 to May 2015, a total of 56 retrievable metallic stents with fixation string were placed under fluoroscopy guidance in 42 patients who were diagnosed with benign anastomotic stricture after UGI surgery. Clinical success was defined as achieving normal regular diet (NRD). Results The clinical success rate after the first stent placement was 57.1% (24/42). After repeated stent placement and/or balloon dilation, the clinical success rate was increased to 83.3% (35/42). Six (14.3%) patients required surgical revision to achieve NRD. One (2.4%) patient failed to achieve NRD. Stent migration occurred in 60.7% (34/56) of patients. Successful rate of removing the stent using fixation string and angiocatheter was 94.6% (53/56). Distal migration occurred in 12 stents. Of the 12 stents, 10 (83.3%) were successfully removed whereas 2 could not be removed. No complication occurred regarding distal migration. Conclusion Using retrievable metallic stent with a fixation string is a feasible option for managing early benign anastomotic stricture after UGI surgery. It can reduce complications caused by distal migration of the stent. PMID:27833405

  20. Cost-effectiveness and clinical efficacy of biliary stents in patients undergoing neoadjuvant therapy for pancreatic adenocarcinoma in a randomized controlled trial.

    PubMed

    Gardner, Timothy B; Spangler, Chad C; Byanova, Katerina L; Ripple, Gregory H; Rockacy, Matthew J; Levenick, John M; Smith, Kerrington D; Colacchio, Thomas A; Barth, Richard J; Zaki, Bassem I; Tsapakos, Michael J; Gordon, Stuart R

    2016-09-01

    The optimal type of stent for the palliation of malignant biliary obstruction in patients with pancreatic adenocarcinoma undergoing neoadjuvant chemoradiotherapy with curative intent is unknown. We performed a prospective trial comparing 3 types of biliary stents-fully covered self-expandable metal (fcSEMS), uncovered self-expandable metal (uSEMS), and plastic-to determine which best optimized cost-effectiveness and important clinical outcomes. In this prospective randomized trial, consecutive patients with malignant biliary obstruction from newly diagnosed pancreatic adenocarcinoma who were to start neoadjuvant chemoradiotherapy were randomized to receive fcSEMSs, uSEMSs, or plastic stents during the index ERCP. The primary outcomes were time to stent occlusion, attempted surgical resection, or death after the initiation of neoadjuvant therapy, and the secondary outcomes were total patient costs associated with the stent, including the index ERCP cost, downstream hospitalization cost due to stent occlusion, and the cost associated with procedural adverse event. Fifty-four patients were randomized and reached the primary end point: 16 in the fcSEMS group, 17 in the uSEMS group, and 21 in the plastic stent group. No baseline demographic or tumor characteristic differences were noted among the groups. The fcSEMSs had a longer time to stent occlusion compared with uSEMSs and plastic stents (220 vs 74 and 76 days, P < .01), although the groups had equivalent rates of stent occlusion, attempted surgical resection, and death. Although SEMS placement cost more during the index ERCP (uSEMS = $24,874 and fcSEMS = $22,729 vs plastic = $18,701; P < .01), they resulted in higher procedural AE costs per patient (uSEMS = $5522 and fcSEMS = $12,701 vs plastic = $0; P < .01). Conversely, plastic stents resulted in an $11,458 hospitalization cost per patient due to stent occlusion compared with $2301 for uSEMSs and $0 for fcSEMSs (P < .01). In a prospective trial