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Sample records for portosystemic shunt histologic

  1. Transjugular intrahepatic portosystemic shunt (TIPS)

    MedlinePlus

    ... gov/ency/article/007210.htm Transjugular intrahepatic portosystemic shunt (TIPS) To use the sharing features on this page, please enable JavaScript. Transjugular intrahepatic portosystemic shunt (TIPS) is a procedure to create new connections ...

  2. Transjugular Intrahepatic Portosystemic Shunt: Histologic and Immunohistochemical Study of Autopsy Cases

    SciTech Connect

    Terayama, Noboru; Matsui, Osamu; Kadoya, Masumi; Yoshikawa, Jun; Gabata, Toshifumi; Miyayama, Shiro; Takashima, Tsutomu; Kobayashi, Kenichi; Nakanishi, Isao; Nakanuma, Yasuni

    1997-11-15

    Purpose: To assess the histologic findings associated with stenosed and occluded transjugular intrahepatic portosystemic shunt (TIPS) tracts. Methods: Four TIPS tracts within three autopsy livers were histologically studied for vascular components by routine staining and immunohistochemical staining. TIPS had been performed for bleeding from esophageal varices in patients with cirrhosis of the liver. Results: Two TIPS, examined on days 4 and 53, showed occlusion by fibrin thrombus. In the former, no endothelial cells were detected, but coagulative necrosis of hepatocytes was found in the surrounding liver. In the latter, bile pigments were seen on the luminal surface. In the two other TIPS without tract occlusion, examined on days 49 and 293, a layer of endothelial cells, proliferation of smooth muscle cells, and deposition of an extracellular matrix such as collagen were confirmed. In the tract examined on day 293, there was protrusion of hepatocytes into the lumen through the stent wires. Conclusion: Short- and midterm TIPS occlusions were caused by thrombus forming after necrosis of hepatocytes and bile leakage, respectively. Long-term TIPS stenosis was associated with a combination of pseudointimal hyperplasia and ingrowth of hepatocytes.

  3. Transjugular intrahepatic portosystemic shunt.

    PubMed

    Patidar, Kavish R; Sydnor, Malcolm; Sanyal, Arun J

    2014-11-01

    Transjugular intrahepatic portosystemic shunt (TIPS) is an established procedure for the complications of portal hypertension. The largest body of evidence for its use has been supported for recurrent or refractory variceal bleeding and refractory ascites. Its use has also been advocated for acute variceal bleed, hepatic hydrothorax, and hepatorenal syndrome. With the replacement of bare metal stents with polytetrafluoroethylene-covered stents, shunt patency has improved dramatically, thus, improving outcomes. Therefore, reassessment of its utility, management of its complications, and understanding of various TIPS techniques is important. PMID:25438287

  4. Transjugular intrahepatic portosystemic shunt.

    PubMed

    Ochs, Andreas

    2005-01-01

    The transjugular intrahepatic portosystemic shunt (TIPS) is an interventional treatment resulting in decompression of the portal system by creation of a side-to-side portosystemic anastomosis. Since its introduction 16 years ago, more than 1,000 publications have appeared demonstrating broad acceptance and increasing clinical use. This review summarizes our present knowledge about technical aspects and complications, follow-up of patients and indications. A technical success rate near 100% and a low occurrence of complications clearly depend on the skills of the operator. The follow-up of the TIPS patient has to assess shunt patency, liver function, hepatic encephalopathy and the possible development of hepatocellular carcinoma. Shunt patency can best be monitored by duplex sonography and can avoid routine radiological revision. Short-term patency may be improved by anticoagulation, while such a treatment does not influence long-term patency. Stent grafts covered with expanded polytetrafluoroethylene show promising long-term patency comparable with that of surgical shunts. With respect to the indications of TIPS, much is known about treatment of variceal bleeding and refractory ascites. The thirteen randomized studies that are available to date show that survival is comparable in patients receiving TIPS or endoscopic treatment for acute or recurrent variceal bleeding. Another group comprises patients with refractory ascites and related complications, such as hepatorenal syndrome and hepatic hydrothorax. It has been demonstrated that TIPS improves these complications. Five randomized studies comparing TIPS with paracentesis and one study comparing TIPS with the peritoneo-venous shunt showed good response of ascites but controversial results on survival. In addition, TIPS has been successfully applied to patients with Budd-Chiari syndrome, portal vein thrombosis, before liver transplantation, and for the treatment of ectopic variceal bleeding. PMID:15920326

  5. Congenital Portosystemic Shunt: Our Experience

    PubMed Central

    Timpanaro, Tiziana; Passanisi, Stefano; Sauna, Alessandra; Trombatore, Claudia; Pennisi, Monica; Petrillo, Giuseppe; Smilari, Pierluigi; Greco, Filippo

    2015-01-01

    Introduction. Congenital portosystemic venous malformations are rare abnormalities in which the portal blood drains into a systemic vein and which are characterized by extreme clinical variability. Case Presentations. The authors present two case reports of a congenital extrahepatic portosystemic shunt (Type II). In the first patient, apparently nonspecific symptoms, such as headache and fatigue, proved to be secondary to hypoglycemic episodes related to the presence of a portosystemic shunt, later confirmed on imaging. During portal vein angiography, endovascular embolization of the portocaval fistula achieved occlusion of the anomalous venous tract. In the second patient, affected by Down's syndrome, the diagnosis of a portosystemic malformation was made by routine ultrasonography, performed to rule out concurrent congenital anomalies. Because of the absence of symptoms, we chose to observe this patient. Conclusions. These two case reports demonstrate the clinical heterogeneity of this malformation and the need for a multidisciplinary approach. As part of a proper workup, clinical evaluation must always be followed by radiographic diagnosis. PMID:25709849

  6. Embolization of nonvariceal portosystemic collaterals in transjugular intrahepatic portosystemic shunts

    SciTech Connect

    Bilbao, Jose Ignacio; Arias, Mercedes; Longo, Jesus Maria; Alejandre, Pedro Luis; Betes, Maria Teresa; Elizalde, Arlette Maria

    1997-03-15

    Percutaneous embolization of large portosystemic collaterals was performed in three patients following placement of a transjugular intrahepatic portosystemic shunt in order to improve hepatopetal portal flow. Improved hepatic portal perfusion was achieved in these cases, thereby theoretically reducing the risk of chronic hepatic encephalopathy.

  7. Canine congenital portosystemic shunts: Disconnections dissected.

    PubMed

    Van den Bossche, L; van Steenbeek, F G

    2016-05-01

    Canine congenital portosystemic shunts (CPSS) are vascular anomalies that connect the portal vein with the systemic circulation, therefore bypassing the hepatic parenchyma. Portosystemic shunts exist in two different subtypes: extrahepatic and intrahepatic. This congenital disorder is also described in mice, cat, sheep and man. Research has been focused on pathophysiology, diagnostics and treatment of CPSS and this has resulted in increased knowledge, although the aetiology of the disease remains unclear. This review focuses on the aetiology and genetic basis of both intra- and extrahepatic shunts. PMID:27061656

  8. A canine model of multiple portosystemic shunting.

    PubMed

    Howe, L M; Boothe, H W; Miller, M W; Boothe, D M

    2000-01-01

    The objective of this study was to develop and describe an experimental canine model of multiple acquired portosystemic shunts (PSS) similar in nature to spontaneously occurring PSS. Sixteen dogs were used and were divided into a control (n = 6) and a diseased group (n = 10). Dogs of the diseased group were administered dimethylnitrosamine (2 mg/kg of body weight, po) twice weekly, and clinicopathologic, ultrasonographic, and hepatic scintigraphic findings were recorded during the development of hepatic disease and PSS. Surgery was then performed to permit visual verification of multiple shunts, catheter placement for portography examination, and biopsy of the liver. All diseased dogs developed severe hepatic disease and multiple PSS as documented visually at surgery and on portography. Based on this study, dimethylnitrosamine-induced portosystemic shunting appears to be an appropriate model for spontaneously occurring multiple PSS secondary to portal hypertension. PMID:10741951

  9. Current concepts in congenital portosystemic shunts.

    PubMed

    Mankin, Kelley M Thieman

    2015-05-01

    Congenital portosystemic shunts (CPSS) are vascular abnormalities that allow portal blood to bypass the liver and join systemic circulation. Laboratory and imaging studies are performed preoperatively to diagnose CPSS and hopefully identify an anatomic location of the shunt. CPSS can be found in different locations in both small and large breed dogs. Most CPSS are best managed surgically. The goal of surgical management of CPSS is to slowly redirect blood from the shunting vessel through the portal vasculature while avoiding portal hypertension. Many surgical management methods are available, including open and less invasive procedures, such as laparoscopy and embolization. PMID:25737000

  10. A large spontaneous intrahepatic portosystemic shunt in a cirrhotic patient

    PubMed Central

    Qi, Xingshun; Ye, Chun; Hou, Yue; Guo, Xiaozhong

    2016-01-01

    Summary A spontaneous portosystemic shunt is a rare malformation of the vessels supplying the liver. This condition often leads to the development of hepatic encephalopathy due to excessive shunting of blood from the portal vein to the inferior vena cava. Some studies have suggested that the presence of spontaneous portosystemic shunts is inversely associated with the appearance of large esophageal varices. Spontaneous intrahepatic portosystemic shunts (SIPSS) are far less frequently observed than extrahepatic portosystemic shunts, which include spleno-gastric-renal shunts, mesenteric-caval shunts, and a large patent umbilical vein. Reported here is a case of decompensated liver cirrhosis with a large SIPSS without any incidence of overt hepatic encephalopathy. PMID:26989653

  11. Portosystemic Shunt Surgery in Patients with Idiopathic Noncirrhotic Portal Hypertension.

    PubMed

    Karagul, Servet; Yagci, Mehmet Ali; Tardu, Ali; Ertugrul, Ismail; Kirmizi, Serdar; Sumer, Fatih; Isik, Burak; Kayaalp, Cuneyt; Yilmaz, Sezai

    2016-01-01

    BACKGROUND Idiopathic noncirrhotic portal hypertension (INCPH) is a rare disease characterized by increased portal venous pressure in the absence of cirrhosis and other causes of liver diseases. The aim of the present study was to present our results in using portosystemic shunt surgery in patients with INCPH. MATERIAL AND METHODS Patients who had been referred to our Liver Transplantation Institute for liver transplantation and who had undergone surgery from January 2010 to December 2015 were retrospectively analyzed. Patients with INCPH who had undergone portosystemic shunt procedure were included in the study. Age, sex, symptoms and findings, type of portosystemic shunt, and postoperative complications were assessed. RESULTS A total of 1307 patients underwent liver transplantation from January 2010 to December 2015. Eleven patients with INCPH who did not require liver transplantation were successfully operated on with a portosystemic shunt procedure. The mean follow-up was 30.1±19 months (range 7-69 months). There was no mortality in the perioperative period or during the follow-up. Two patients underwent surgery again due to intra-abdominal hemorrhage; one had bleeding from the surgical site except the portacaval anastomosis and the other had bleeding from the h-graft anastomosis. No patient developed encephalopathy and no patient presented with esophageal variceal bleeding after portosystemic shunt surgery. Shunt thrombosis occurred in 1 patient (9.9%). Only 1 patient developed ascites, which was controlled medically. CONCLUSIONS Portosystemic shunt surgery is a safe and effective procedure for the treatment of patients with INCPH. PMID:27194018

  12. Current status of transjugular intrahepatic portosystemic shunts.

    PubMed Central

    Patel, N. H.; Chalasani, N.; Jindal, R. M.

    1998-01-01

    The use of the transjugular intrahepatic portosystemic shunt (TIPS) has emerged as an important nonoperative modality for variceal bleeding, intractable ascites, and for selected cases of hepatic venous obstruction. We believe that TIPS should be viewed as a 'bridge' to liver transplantation and should be carried out only in experienced centres. The adverse haemodynamic changes on the cardiopulmonary system after TIPS should be borne in mind. Prospective trials to evaluate the role of TIPS versus sclerotherapy in variceal bleeding will be watched with interest. There is, however, an urgent need to improve long-term results of TIPS as stent thrombosis and stenosis occur frequently. We advocate routine surveillance to detect these problems at an early stage. PMID:10320885

  13. Transjugular Intrahepatic Portosystemic Shunt Complications: Prevention and Management

    PubMed Central

    Suhocki, Paul V.; Lungren, Matthew P.; Kapoor, Baljendra; Kim, Charles Y.

    2015-01-01

    Transjugular intrahepatic portosystemic shunt (TIPS) insertion has been well established as an effective treatment in the management of sequelae of portal hypertension. There are a wide variety of complications that can be encountered, such as hemorrhage, encephalopathy, TIPS dysfunction, and liver failure. This review article summarizes various approaches to preventing and managing these complications. PMID:26038620

  14. Predictors of mortality after transjugular portosystemic shunt

    PubMed Central

    Ascha, Mona; Abuqayyas, Sami; Hanouneh, Ibrahim; Alkukhun, Laith; Sands, Mark; Dweik, Raed A; Tonelli, Adriano R

    2016-01-01

    AIM: To investigate if echocardiographic and hemodynamic determinations obtained at the time of transjugular intrahepatic portosystemic shunt (TIPS) can provide prognostic information that will enhance risk stratification of patients. METHODS: We reviewed medical records of 467 patients who underwent TIPS between July 2003 and December 2011 at our institution. We recorded information regarding patient demographics, underlying liver disease, indication for TIPS, baseline laboratory values, hemodynamic determinations at the time of TIPS, and echocardiographic measurements both before and after TIPS. We recorded patient comorbidities that may affect hemodynamic and echocardiographic determinations. We also calculated Model for End-stage Liver Disease (MELD) score and Child Turcotte Pugh (CTP) class. The following pre- and post-TIPS echocardiographic determinations were recorded: Left ventricular ejection fraction, right ventricular (RV) systolic pressure, subjective RV dilation, and subjective RV function. We recorded the following hemodynamic measurements: Right atrial (RA) pressure before and after TIPS, inferior vena cava pressure before and after TIPS, free hepatic vein pressure, portal vein pressure before and after TIPS, and hepatic venous pressure gradient (HVPG). RESULTS: We reviewed 418 patients with portal hypertension undergoing TIPS. RA pressure increased by a mean ± SD of 4.8 ± 3.9 mmHg (P < 0.001), HVPG decreased by 6.8 ± 3.5 mmHg (P < 0.001). In multivariate linear regression analysis, a higher MELD score, lower platelet count, splenectomy and a higher portal vein pressure were independent predictors of higher RA pressure (R = 0.55). Three variables predicted 3-mo mortality after TIPS in a multivariate analysis: Age, MELD score, and CTP grade C. Change in the RA pressure after TIPS predicted long-term mortality (per 1 mmHg change, HR = 1.03, 95%CI: 1.01-1.06, P < 0.012). CONCLUSION: RA pressure increased immediately after TIPS particularly in

  15. Congenital intrahepatic portosystemic shunts: Imaging findings and endovascular management.

    PubMed

    Chandrasekharan, Rajsekar; Pullara, Sreekumar K; Thomas, Tixon; Kader, Nazar Puthukudiyil; Moorthy, Srikanth

    2016-01-01

    We present two cases of congenital intrahepatic portosystemic shunts in which the right portal vein directly communicated with the inferior venacava (IVC) in one patient and with the hepatic vein in the other. Multiple hepatic nodules consistent with focal nodular hyperplasia (FNH) were seen in the first patient. The second patient presented with recurrent history of hepatic encephalopathy. Percutaneous transhepatic embolization was performed using coils and Amplatz device following which she completely recovered. PMID:27081230

  16. Congenital intrahepatic portosystemic shunts: Imaging findings and endovascular management

    PubMed Central

    Chandrasekharan, Rajsekar; Pullara, Sreekumar K; Thomas, Tixon; Kader, Nazar Puthukudiyil; Moorthy, Srikanth

    2016-01-01

    We present two cases of congenital intrahepatic portosystemic shunts in which the right portal vein directly communicated with the inferior venacava (IVC) in one patient and with the hepatic vein in the other. Multiple hepatic nodules consistent with focal nodular hyperplasia (FNH) were seen in the first patient. The second patient presented with recurrent history of hepatic encephalopathy. Percutaneous transhepatic embolization was performed using coils and Amplatz device following which she completely recovered. PMID:27081230

  17. Transjugular Intrahepatic Portosystemic Shunt before and after Liver Transplantation.

    PubMed

    Saad, Wael E

    2014-09-01

    The transjugular intrahepatic portosystemic shunt (TIPS) has long been referred to as a procedure performed as "a bridge to transplantation" since, like many other portosystemic shunts, it decompresses the portal circulation and stabilizes patients but does not definitively treat portal hypertension. One of the major advantages of TIPS over surgically placed portosystemic shunts in the transplant era is that the TIPS is intrahepatic and is removed in situ with the native liver, and usually does not need additional surgery (unlike takedown/ligation of surgical shunts). There are several studies that evaluate TIPS before transplantation-not as a bridge/temporizing measure, but as a prelude to the transplant to decompress the portal circulation and reduce portosystemic engorgement and collaterals and thus, in theory, reduce intraoperative bleeding during liver transplantation. However, these studies, mostly in the transplant literature, have been equivocal from an intraoperative and posttransplant clinical outcome standpoint. TIPS creation in liver transplant recipients is another interesting aspect of TIPS. There has been a debate about whether or not liver transplantation adds additional technical difficulty to the TIPS procedure. Initially, many theories were proposed as to the technical difficulty of TIPS in a transplanted liver. However, recent opinions and published studies demonstrate that whole-graft liver transplantation does not pose a significant technical difficulty to TIPS. Moreover, there are several recent studies evaluating the outcomes of TIPS in liver transplant recipients, showing that outcomes are less favorable when compared with TIPS in nontransplanted patients. This article discusses the results of TIPS as a preoperative prelude to liver transplantation. In addition, it discusses the technical and clinical outcomes of TIPS in liver transplant recipients. PMID:25177084

  18. Pulmonary Arterial Hypertension Associated with Congenital Portosystemic Shunts Treated with Transcatheter Embolization and Pulmonary Vasodilators.

    PubMed

    Sato, Haruka; Miura, Masanobu; Yaoita, Nobuhiro; Yamamoto, Saori; Tatebe, Shunsuke; Aoki, Tatsuo; Satoh, Kimio; Ota, Hideki; Takase, Kei; Sugimura, Koichiro; Shimokawa, Hiroaki

    2016-01-01

    Cardiopulmonary abnormalities are often present in patients with liver diseases. We herein report a case of congenital portosystemic shunts complicated by hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PoPH). A 57-year-old woman complained of dyspnea and was subsequently diagnosed with HPS and PoPH caused by congenital portosystemic shunts. Although shunt closure by transcatheter embolization was successfully performed, her dyspnea worsened and pulmonary artery pressure and pulmonary vascular resistance elevated. Conventional vasodilator therapy was started, resulting in an improvement of pulmonary hypertension (PH). In some patients with congenital portosystemic shunts, shunt closure could exacerbate PH, and vasodilator therapy may be effective. PMID:27580545

  19. The Transjugular Intrahepatic Portosystemic Shunt: Technique and Instruments.

    PubMed

    Keller, Frederick S; Farsad, Khashayar; Rösch, Josef

    2016-03-01

    Although transjugular intrahepatic portosystemic shunt (TIPS) was first described in 1971, it took 15 more years for technology, in the form of expandable metallic stents, to be developed to make TIPS a viable, widespread clinical procedure. Currently, expanded polytetrafluoroethylene-covered stent grafts that exhibit significantly greater long-term patency are used for TIPS creation by most interventionalists. TIPS creation requires specific interventional skills, tools, and devices for success. In the hands of skillful, experienced interventional radiologists, TIPS creation is performed safely and successfully in greater than 95% of cases. PMID:26997084

  20. The Evolution of Transjugular Intrahepatic Portosystemic Shunt: Tips

    PubMed Central

    Fanelli, Fabrizio

    2014-01-01

    Since Richter's description in the literature in 1989 of the first procedure on human patients, transjugular intrahepatic portosystemic shunt (TIPS) has been worldwide considered as a noninvasive technique to manage portal hypertension complications. TIPS succeeds in lowering the hepatic sinusoidal pressure and in increasing the circulatory flow, thus reducing sodium retention, ascites recurrence, and variceal bleeding. Required several revisions of the shunt TIPS can be performed in case of different conditions such as hepatorenal syndrome, hepatichydrothorax, portal vein thrombosis, and Budd-Chiari syndrome. Most of the previous studies on TIPS procedure were based on the use of bare stents and most patients chose TIPS 2-3 years after traditional treatment, thus making TIPS appear to be not superior to endoscopy in survival rates. Bare stents were associated with higher incidence of shunt failure and consequently patients required several revisions during the follow-up. With the introduction of a dedicated e-PTFE covered stent-graft, these problems were completely solved, No more reinterventions are required with a tremendous improvement of patient's quality of life. One of the main drawbacks of the use of e-PTFE covered stent-graft is higher incidence of hepatic encephalopathy. In those cases refractory to the conventional medical therapy, a shunt reduction must be performed. PMID:27335841

  1. The Evolution of Transjugular Intrahepatic Portosystemic Shunt: Tips.

    PubMed

    Fanelli, Fabrizio

    2014-01-01

    Since Richter's description in the literature in 1989 of the first procedure on human patients, transjugular intrahepatic portosystemic shunt (TIPS) has been worldwide considered as a noninvasive technique to manage portal hypertension complications. TIPS succeeds in lowering the hepatic sinusoidal pressure and in increasing the circulatory flow, thus reducing sodium retention, ascites recurrence, and variceal bleeding. Required several revisions of the shunt TIPS can be performed in case of different conditions such as hepatorenal syndrome, hepatichydrothorax, portal vein thrombosis, and Budd-Chiari syndrome. Most of the previous studies on TIPS procedure were based on the use of bare stents and most patients chose TIPS 2-3 years after traditional treatment, thus making TIPS appear to be not superior to endoscopy in survival rates. Bare stents were associated with higher incidence of shunt failure and consequently patients required several revisions during the follow-up. With the introduction of a dedicated e-PTFE covered stent-graft, these problems were completely solved, No more reinterventions are required with a tremendous improvement of patient's quality of life. One of the main drawbacks of the use of e-PTFE covered stent-graft is higher incidence of hepatic encephalopathy. In those cases refractory to the conventional medical therapy, a shunt reduction must be performed. PMID:27335841

  2. Percutaneous rheolytic mechanical thrombectomy in thrombosed direct intrahepatic portosystemic shunt: Report of two cases

    PubMed Central

    Tsetis, Dimitrios; Kehagias, Elias; Samonakis, Dimitrios; Kouroumalis, Elias; Hatzidakis, Adam

    2015-01-01

    We report two patients with Budd–Chiari syndrome, who underwent direct intrahepatic portosystemic shunt complicated by shunt thrombosis. Percutaneous AngioJet mechanical thrombectomy in combination with manual catheter aspiration and balloon disruption of the residual clot was successful, restoring patency of the thrombosed shunt. PMID:26767124

  3. Transjugular Intrahepatic Portosystemic Shunt Versus Surgical Shunting in the Management of Portal Hypertension

    PubMed Central

    Huang, Long; Yu, Qing-Sheng; Zhang, Qi; Liu, Ju-Da; Wang, Zhen

    2015-01-01

    Background: The purpose of this article was to clarify the optimal management concerning transjugular intrahepatic portosystemic shunts (TIPSs) and surgical shunting in treating portal hypertension. Methods: All databases, including CBM, CNKI, WFPD, Medline, EMBASE, PubMed and Cochrane up to February 2014, were searched for randomized controlled trials (RCTs) comparing TIPS with surgical shunting. Four RCTs, which were extracted by two independent investigators and were evaluated in postoperative complications, mortality, 2- and 5-year survival, hospital stay, operating time and hospitalization charges. Results: The morbidity in variceal rehemorrhage was significantly higher in TIPS than in surgical shunts (odds ratio [OR] = 7.45, 95% confidence interval[CI]: (3.93–14.15), P < 0.00001), the same outcomes were seen in shunt stenosis (OR = 20.01, 95% CI: (6.67–59.99), P < 0.000001) and in hepatic encephalopathy (OR = 2.50, 95% CI: (1.63–3.84), P < 0.0001). Significantly better 2-year survival (OR = 0.66; 95% CI: (0.44–0.98), P = 0.04) and 5-year survival (OR = 0.44; 95% CI: (0.30–0.66), P < 0.00001) were seen in patients undergoing surgical shunting compared with TIPS. Conclusions: Compared with TIPS, postoperative complications and survival after surgical shunting were superior for patients with portal hypertension. Application of surgical shunting was recommended for patients rather than TIPS. PMID:25758281

  4. Emphysematous pyonephrosis associated with extrahepatic portosystemic shunt in a dog

    PubMed Central

    LIM, Jongsu; YOON, Youngmin; JUNG, Dongin; YEON, Seongchan; LEE, Heechun

    2015-01-01

    A 16-month-old intact female Maltese dog was referred for examination of depression and vomiting. Ultrasonography revealed dilated right renal pelvis containing echogenic fluid with free gas. A hyperechoic material suspected of urolith was identified in the right ureter. Computed tomography revealed emphysematous change of the right kidney associated with ureteral obstruction and extrahepatic portosystemic shunt (EHPSS). Ureteronephrectomy and surgical correction were performed for the EHPSS. Escherichia coli was isolated from pus from the right kidney. Quantitative analysis revealed that the urolith was an ammonium urate stone. After 5 months follow-up, no complication was observed. This is the first report of emphysematous pyonephrosis associated with EHPSS in a dog. PMID:26668166

  5. Treatment of Portosystemic Shunt Myelopathy with a Stent Graft Deployed through a Transjugular Intrahepatic Route

    SciTech Connect

    Jain, Deepak Arora, Ankur; Deka, Pranjal; Mukund, Amar Bhatnagar, Shorav; Jindal, Deepti Kumar, Niteen Pamecha, Viniyendra

    2013-08-01

    A case of surgically created splenorenal shunt complicated with shunt myelopathy was successfully managed by placement of a stent graft within the splenic vein to close the portosystemic shunt and alleviate myelopathy. To our knowledge, this is the first report of a case of shunt myelopathy in a patient with noncirrhotic portal fibrosis without cirrhosis treated by a novel technique wherein a transjugular intrahepatic route was adopted to deploy the stent graft.

  6. Transjugular Intrahepatic Portosystemic Shunts in Children with Biliary Atresia

    SciTech Connect

    Huppert, Peter E.; Goffette, Pierre; Sokal, Emil M.; Schweizer, Paul; Claussen, Claus D.

    2002-12-15

    Purpose: We retrospectively evaluated the technical and long-term clinical results of transjugularintrahepatic portosystemic shunts (TIPS) in children with portal hypertension and biliary atresia (BA). Methods: Nine children with BA and recurrent bleeding from esophagogastric and/or intestinal varices were treated by TIPS at the age of 34-156 months and followed-up in two centers. Different types of stents were used. Results: Shunt insertion succeeded in all patients, but in two a second procedure was necessary. Seven procedures lasted more than 3 hr, mainly due to difficult portal vein puncture.Variceal bleeding ceased in all patients; however, 16 reinterventions were performed in eight patients for clinical reasons (n =11) and sonographically suspected restenosis (n =5). Four patients underwent successful liver transplantation 4-51 months after TIPS and five are in good clinical conditions 64-75 months after TIPS. Conclusions: TIPS in children with BA is technically difficult, mainly due to periportal fibrosis and small portal veins. Frequency of reinterventions seems to be higher compared with adults.

  7. Transjugular Intrahepatic Portosystemic Shunt (TIPS): Current Status and Future Possibilities

    SciTech Connect

    Bilbao, Jose Ignacio; Quiroga, Jorge; Herrero, Jose Ignacio; Benito, Alberto

    2002-08-15

    Since the insertion of the first TIPS in 1989 much has been learned about this therapeutic procedure. It has an established role for the treatment of some complications of portal hypertension: prevention of recurrent variceal bleeding and rescue of patients with acute uncontrollable variceal bleeding. In addition TIPS is useful for Budd-Chiari syndrome, refractory ascites and hepatorenal syndrome, although its specific role in these indications remains to be definitively established. However, the decrease in sinusoidal blood flow induced by TIPS can lead to the patient developing hepatic encephalopathy and liver failure in some cases. Therefore, TIPS should be used with caution in patients with very poor liver function. From a technical point of view, successful placement of TIPS is achieved in more than 98% of cases by experienced groups. At present, evaluation of TIPS dysfunction based on morphology probably leads to an overdiagnosis of this complication since most of these cases are not associated with clinical manifestations (recurrent bleeding or refractory ascites). The major disadvantage of TIPS remains its poor long-term patency requiring a mandatory surveillance program. The indicator for shunt function/malfunction should be the portosystemic pressure gradient, which is best assessed by intravascular measurements. Shunt obstructions may be prevented or reduced by the use of stent-grafts in the future.

  8. Hepatic focal nodular hyperplasia with congenital portosystemic shunt.

    PubMed

    Cho, Yuki; Shimono, Taro; Morikawa, Hiroyasu; Shintaku, Haruo; Tokuhara, Daisuke

    2014-12-01

    Hepatic focal nodular hyperplasia (FNH) is a rare benign tumor in children. Vascular anomalies have been identified as pathological features of FNH, but the etiology remains unclear. We describe a rare case including the time course of formation of hepatic FNH in response to congenital portosystemic shunt (PSS). A 4-month-old girl was identified on newborn mass screening to have hypergalactosemia, but no inherited deficiencies in galactose-metabolizing enzymes were found. Ultrasonography and per-rectal portal scintigraphy showed intrahepatic PSS of the right lobe as a cause of the hypergalactosemia. At age 12 months, the patient had elevated hepatic enzymes and small hypoechoic hepatic lesions around the shunt. On abdominal contrast-enhanced ultrasonography spoke-wheel sign and central stellate scar were seen, which are typical features of hepatic FNH without biopsy. Congenital intrahepatic PSS should be evaluated on abdominal contrast-enhanced ultrasonography and observed over time because of its potential to develop into hepatic FNH. PMID:25521987

  9. Transjugular Intrahepatic Portosystemic Shunt Dysfunction: Concordance of Clinical Findings, Doppler Ultrasound Examination, and Shunt Venography

    PubMed Central

    Owen, Joshua M; Gaba, Ron Charles

    2016-01-01

    Objectives: The objective of this study was to evaluate the concordance between clinical symptoms, Doppler ultrasound (US), and shunt venography for the detection of stent-graft transjugular intrahepatic portosystemic shunt (TIPS) dysfunction. Materials and Methods: Forty-one patients (M:F 30:11, median age 55 years) who underwent contemporaneous clinical exam, Doppler US, and TIPS venography between 2003 and 2014 were retrospectively studied. Clinical symptoms (recurrent ascites or variceal bleeding) were dichotomously classified as present/absent, and US and TIPS venograms were categorized in a binary fashion as normal/abnormal. US abnormalities included high/low (>190 or <90 cm/s) TIPS velocity, significant velocity rise/fall (>50 cm/s), absent flow, and return of antegrade intra-hepatic portal flow. Venographic abnormalities included shunt stenosis/occlusion and/or pressure gradient elevation. Clinical and imaging concordance rates were calculated. Results: Fifty-two corresponding US examinations and venograms were assessed. The median time between studies was 3 days. Forty of 52 (77%) patients were symptomatic, 33/52 (64%) US examinations were abnormal, and 20/52 (38%) TIPS venograms were abnormal. Concordance between clinical symptoms and TIPS venography was 48% (25/52), while the agreement between US and shunt venography was 65% (34/52). Clinical symptoms and the US concurred in 60% (31/52) of the patients. The sensitivity of clinical symptoms and US for the detection of venographically abnormal shunts was 80% (16/20) and 85% (17/20), respectively. Both clinical symptoms and the US had low specificity (25%, 8/32 and 50%, 16/32) for venographically abnormal shunts. Conclusion: Clinical findings and the US had low concordance rates with TIPS venography, with acceptable sensitivity but poor specificity. These findings suggest the need for improved noninvasive imaging methods for stent-graft TIPS surveillance. PMID:27563495

  10. Shunting branch of portal vein and stent position predict survival after transjugular intrahepatic portosystemic shunt

    PubMed Central

    Bai, Ming; He, Chuang-Ye; Qi, Xing-Shun; Yin, Zhan-Xin; Wang, Jian-Hong; Guo, Wen-Gang; Niu, Jing; Xia, Jie-Lai; Zhang, Zhuo-Li; Larson, Andrew C; Wu, Kai-Chun; Fan, Dai-Ming; Han, Guo-Hong

    2014-01-01

    AIM: To evaluate the effect of the shunting branch of the portal vein (PV) (left or right) and the initial stent position (optimal or suboptimal) of a transjugular intrahepatic portosystemic shunt (TIPS). METHODS: We retrospectively reviewed 307 consecutive cirrhotic patients who underwent TIPS placement for variceal bleeding from March 2001 to July 2010 at our center. The left PV was used in 221 patients and the right PV in the remaining 86 patients. And, 224 and 83 patients have optimal stent position and sub-optimal stent positions, respectively. The patients were followed until October 2011 or their death. Hepatic encephalopathy, shunt dysfunction, and survival were evaluated as outcomes. The difference between the groups was compared by Kaplan-Meier analysis. A Cox regression model was employed to evaluate the predictors. RESULTS: Among the patients who underwent TIPS to the left PV, the risk of hepatic encephalopathy (P = 0.002) and mortality were lower (P < 0.001) compared to those to the right PV. Patients who underwent TIPS with optimal initial stent position had a higher primary patency (P < 0.001) and better survival (P = 0.006) than those with suboptimal initial stent position. The shunting branch of the portal vein and the initial stent position were independent predictors of hepatic encephalopathy and shunt dysfunction after TIPS, respectively. And, both were independent predictors of survival. CONCLUSION: TIPS placed to the left portal vein with optimal stent position may reduce the risk of hepatic encephalopathy and improve the primary patency rates, thereby prolonging survival. PMID:24574750

  11. Current diagnosis and management of post-transjugular intrahepatic portosystemic shunt refractory hepatic encephalopathy.

    PubMed

    Pereira, Keith; Carrion, Andres F; Martin, Paul; Vaheesan, Kirubahara; Salsamendi, Jason; Doshi, Mehul; Yrizarry, Jose M

    2015-12-01

    Transjugular intrahepatic portosystemic shunt has evolved into an important option for management of complications of portal hypertension. The use of polytetrafluoroethylene covered stents enhances shunt patency. Hepatic encephalopathy (HE) remains a significant problem after TIPS placement. The approach to management of patients with refractory hepatic encephalopathy typically requires collaboration between different specialties. Patient selection for TIPS requires careful evaluation of risk factors for HE. TIPS procedure-related technical factors like stent size, attention to portosystemic pressure gradient reduction and use of adjunctive variceal embolization maybe important. Conservative medical therapy in combination with endovascular therapies often results in resolution or substantial reduction of symptoms. Liver transplantation is, however, the ultimate treatment. PMID:26332169

  12. [Repeat endovascular interventions after transjugular intrahepatic portosystemic shunt (tips) procedures].

    PubMed

    Shipovskiĭ, V N; Tsitsiashvili, M Sh; Saakian, A M; Monakhov, D V; Khuan, Ch; Nechaev, A I

    2010-01-01

    The authors share their experience with transjugular intrahepatic portosystemic shunt (TIPS) procedures preformed in a total of fifty-nine patients diagnosed with and hence operated on for class B and C hepatocirrhosis (according to the Child-Turcotte-Pugh classification), portal hypertension, grade 3 varicosely dilated oesophageal veins, or ascites. Of these, there were 12 women and 47 men (average age 56.3 years). Three types of stents were used: matrix stents (PERICO), self-expanding (ZA-stents, OptiMedsinus-SuperFlex- Visualstents, Zilverstents, SMART), and coated self-expanding stents (Gore Viatorr TIPS Endoprosthesis). Six (11 %) TIPS procedures ended in failure. Of the remaining 53 successful TIPS attempts, thirteen patients developed an in-stent thrombosis at various terms postoperatively, with one patient having experienced it twice Within four postoperative days, thrombosis occurred in three patients, at terms varying from one month to three months in five patients, and from 6 to 12 months in a further five patients. More often thromboses were encountered with the matrix stents (n = 3) 23.0% (PERICO) and self-expanding stents (n = 8) in 61.0% (OptiMed sinus-SuperFlex-Visual). Thromboses were clinically manifested by oesophageal variceal haemorrhage. An in-stent thrombosis was confirmed by means of ultrasonographic duplex scanning (lack of arterial blood flow). The primary stent patency rate following TIPS procedures amounted to 67%. with the secondary assisted graft patency rate equalling 89%. Restoration of the stent's lumen after TIPS procedures by means of endovascular recanalization, rheolytic thrombectomy, balloon angioplasty, and a stent-in-stent technique appears to be a minimally invasive, rather efficient method and virtually the only way to preserve the stent's patency. This technique makes it possible to decrease the rate of recurrent oesophageal variceal haemorrhage. PMID:21032871

  13. Transjugular intrahepatic portosystemic shunts and portal hypertension-related complications

    PubMed Central

    Siramolpiwat, Sith

    2014-01-01

    Portal hypertension (PH) plays an important role in the natural history of cirrhosis, and is associated with several clinical consequences. The introduction of transjugular intrahepatic portosystemic shunts (TIPS) in the 1980s has been regarded as a major technical advance in the management of the PH-related complications. At present, polytetrafluoroethylene-covered stents are the preferred option over traditional bare metal stents. TIPS is currently indicated as a salvage therapy in patients with bleeding esophageal varices who fail standard treatment. Recently, applying TIPS early (within 72 h after admission) has been shown to be an effective and life-saving treatment in those with high-risk variceal bleeding. In addition, TIPS is recommended as the second-line treatment for secondary prophylaxis. For bleeding gastric varices, applying TIPS was able to achieve hemostasis in more than 90% of patients. More trials are needed to clarify the efficacy of TIPS compared with other treatment modalities, including cyanoacrylate injection and balloon retrograde transvenous obliteration of gastric varices. TIPS should also be considered in bleeding ectopic varices and refractory portal hypertensive gastropathy. In patients with refractory ascites, there is growing evidence that TIPS not only results in better control of ascites, but also improves long-term survival in appropriately selected candidates. In addition, TIPS is a promising treatment for refractory hepatic hydrothorax. However, the role of TIPS in the treatment of hepatorenal and hepatopulmonary syndrome is not well defined. The advantage of TIPS is offset by a risk of developing hepatic encephalopathy, the most relevant post-procedural complication. Emerging data are addressing the determination the optimal time and patient selection for TIPS placement aiming at improving long-term treatment outcome. This review is aimed at summarizing the published data regarding the application of TIPS in the management of

  14. Transjugular intrahepatic portosystemic shunts and portal hypertension-related complications.

    PubMed

    Siramolpiwat, Sith

    2014-12-01

    Portal hypertension (PH) plays an important role in the natural history of cirrhosis, and is associated with several clinical consequences. The introduction of transjugular intrahepatic portosystemic shunts (TIPS) in the 1980s has been regarded as a major technical advance in the management of the PH-related complications. At present, polytetrafluoroethylene-covered stents are the preferred option over traditional bare metal stents. TIPS is currently indicated as a salvage therapy in patients with bleeding esophageal varices who fail standard treatment. Recently, applying TIPS early (within 72 h after admission) has been shown to be an effective and life-saving treatment in those with high-risk variceal bleeding. In addition, TIPS is recommended as the second-line treatment for secondary prophylaxis. For bleeding gastric varices, applying TIPS was able to achieve hemostasis in more than 90% of patients. More trials are needed to clarify the efficacy of TIPS compared with other treatment modalities, including cyanoacrylate injection and balloon retrograde transvenous obliteration of gastric varices. TIPS should also be considered in bleeding ectopic varices and refractory portal hypertensive gastropathy. In patients with refractory ascites, there is growing evidence that TIPS not only results in better control of ascites, but also improves long-term survival in appropriately selected candidates. In addition, TIPS is a promising treatment for refractory hepatic hydrothorax. However, the role of TIPS in the treatment of hepatorenal and hepatopulmonary syndrome is not well defined. The advantage of TIPS is offset by a risk of developing hepatic encephalopathy, the most relevant post-procedural complication. Emerging data are addressing the determination the optimal time and patient selection for TIPS placement aiming at improving long-term treatment outcome. This review is aimed at summarizing the published data regarding the application of TIPS in the management of

  15. Congenital extrahepatic portosystemic shunt complicated by the development of hepatocellular carcinoma.

    PubMed

    Sharma, Ruchi; Suddle, Abid; Quaglia, Alberto; Peddu, Praveen; Karani, John; Satyadas, Thomas; Heaton, Nigel

    2015-10-01

    Congenital extrahepatic portosystemic shunt, also known as Abernethy malformation, is a rare congenital malformation. It causes shunting of blood through a communication between the portal and systemic veins such as a patent ductus venous. We report 3 cases of Abernethy malformation complicated by the development of hepatocellular carcinoma. Additionally, we comprehensively reviewed all previously reported cases and highlighted common features that may help in early diagnosis and appropriate management. Patients with Abernethy malformation may have an increased propensity to develop hepatocellular carcinoma. All 5 previously reported cases, plus the three of our patients, have a type 1 (complete) shunt suggesting a role for absent portal blood flow in the pathogenesis of hepatocellular carcinoma. Congenital extrahepatic portosystemic shunt should be sought for in cases with raised serum ammonia, hepatic encephalopathy or hepatocellular carcinoma in the absence of cirrhosis. PMID:26459734

  16. Acute Budd-Chiari syndrome: Treatment with transjugular intrahepatic portosystemic shunt

    SciTech Connect

    Strunk, Holger M.; Textor, Jochen; Brensing, Karl-August; Schild, Hans H.

    1997-07-15

    The case of a 28-year-old man with acute Budd-Chiari syndrome due to veno-occlusive disease is reported. Transjugular intrahepatic portosystemic shunt (TIPS) was performed after upper gastrointestinal endoscopy, duplex sonographic and abdominal computed tomographic examination, inferior cavogram with hepatic venous catheterization, and transvenous biopsy. A 10-mm parenchymal tract was created. The patient did well after the procedure; ascites resolved and liver function improved markedly. The shunt has remained patent up to now for 6 months.

  17. Vascular plug-assisted retrograde transvenous obliteration of portosystemic shunts for refractory hepatic encephalopathy: a case report.

    PubMed

    Park, Jonathan K; Cho, Sung-Ki; Kee, Stephen; Lee, Edward W

    2014-01-01

    While balloon-assisted retrograde transvenous obliteration (BRTO) has been used for two decades in Asia for the management of gastric variceal bleeding, it is still an emerging therapy elsewhere. Given the shunt closure brought about by the procedure, BRTO has also been used for the management of portosystemic encephalopathy with promising results. Modified versions of BRTO have been developed, including plug-assisted retrograde transvenous obliteration (PARTO), where a vascular plug is deployed within a portosystemic shunt. To our knowledge, we present the first North American case of PARTO in the setting of a large splenorenal shunt for the management of portosystemic encephalopathy. PMID:24744943

  18. Post-Transjugular Intrahepatic Portosystemic Shunt Follow-Up and Management in the VIATORR Era.

    PubMed

    Ferral, Hector; Gomez-Reyes, Elisa; Fimmel, Claus J

    2016-03-01

    The transjugular intrahepatic portosystemic shunt (TIPS) is a non-selective portosystemic shunt created using endovascular techniques. The first TIPS was performed in Germany in 1988. The VIATORR self-expandable PTFE covered stent-graft (WL Gore, Flagstaff AZ) was approved by the FDA for a TIPS application in December of 2004. This stent-graft offers excellent shunt patency rates and it is possible that it has a beneficial effect on patient survival. Patient surveillance and post-procedural management have changed after the introduction of this stent-graft. This article presents the current management strategies that are followed at our Institution for patients who have undergone a TIPS procedure with a VIATORR stent graft including imaging follow-up, management of encephalopathy, medical management and nutritional aspects. PMID:26997092

  19. Distribution of extrahepatic congenital portosystemic shunt morphology in predisposed dog breeds

    PubMed Central

    2012-01-01

    Background An inherited basis for congenital extrahepatic portosystemic shunts (EHPSS) has been demonstrated in several small dog breeds. If in general both portocaval and porto-azygous shunts occur in breeds predisposed to portosystemic shunts then this could indicate a common genetic background. This study was performed to determine the distribution of extrahepatic portocaval and porto-azygous shunts in purebred dog populations. Results Data of 135 client owned dogs diagnosed with EHPSS at the Faculty of Veterinary Medicine of Utrecht University from 2001 – 2010 were retrospectively analyzed. The correlation between shunt localization, sex, age, dog size and breed were studied. The study group consisted of 54 males and 81 females from 24 breeds. Twenty-five percent of dogs had porto-azygous shunts and 75% had portocaval shunts. Of the dogs with porto-azygous shunts only 27% was male (P = 0.006). No significant sex difference was detected in dogs with a portocaval shunt. Both phenotypes were present in almost all breeds represented with more than six cases. Small dogs are mostly diagnosed with portocaval shunts (79%) whereas both types are detected. The age at diagnosis in dogs with porto-azygous shunts was significantly higher than that of dogs with portocaval shunts (P < 0.001). Conclusion The remarkable similarity of phenotypic variation in many dog breeds may indicate common underlying genes responsible for EHPSS across breeds. The subtype of EHPSS could be determined by a minor genetic component or modulating factors during embryonic development. PMID:22784395

  20. Computed tomographic morphology and clinical features of extrahepatic portosystemic shunts in 172 dogs in Japan.

    PubMed

    Fukushima, K; Kanemoto, H; Ohno, K; Takahashi, M; Fujiwara, R; Nishimura, R; Tsujimoto, H

    2014-03-01

    Canine extrahepatic congenital portosystemic shunts (EH-cPSS) are classified into several anatomical types, depending on the origin and termination of the shunt vessel. The aim of this retrospective study was to determine the proportion and clinical features of each anatomical shunt type in a population of dogs presented to a veterinary teaching hospital in Japan. Dogs diagnosed with EH-cPSS using computed tomographic (CT) portography were included (n=172) and shunts were classified based on previous reports. Clinical data were collected from case records and analysed statistically. The most common anatomical type was the spleno-phrenic shunt (n=64), followed by the spleno-azygos (n=38), right gastric-caval (n=29), spleno-caval (n=21), right gastric-caval with caudal loop (n=9), right gastric-phrenic (n=6), colono-caval (n=3), spleno-phrenic and azygos (n=1), and porto-caval (n=1) shunts. Spleno-phrenic and spleno-azygos shunts were diagnosed more frequently in older dogs than right gastric-caval and spleno-caval shunts (P<0.05). The portal vein/aortic (PV/Ao) ratio was significantly larger in dogs with spleno-phrenic shunts than in dogs with spleno-azygos, right gastric-caval or spleno-caval shunts (P<0.05). The PV/Ao ratio was significantly larger in dogs with spleno-azygos shunts than in dogs with right gastric-caval shunts. Dogs with spleno-phrenic shunts had significantly lower serum alkaline phosphatase activities than those with right gastric-caval or spleno-caval shunts. Dogs with spleno-phrenic shunts had significantly lower fasting ammonia concentrations than those with spleno-caval shunts. PMID:24512983

  1. T1-201 per rectum: A noninvasive method for evaluating portosystemic shunt

    SciTech Connect

    Verdickt, X.; Reding, P.; Tshiamala, P.; Ham, H.R.

    1984-01-01

    Portosystemic shunt is one of the most important complications of liver cirrhosis. Unfortunately, current methods for detecting and quantifying this shunt are either non-specific or associated with significant morbidity. The aim of this work was to evaluate the clinical value of a new non-traumatic method which consisted of administrating T1-201 per rectum and monitoring the absorbed activity using a camera and a computer system. The method assumes that in the absence of portosystemic shunt, most of the absorbed activity will be fixed in the liver while in the presence of this shunt, some of the activity will be fixed in the myocardium. The ratio of heart to liver activity can therefore be used to evaluate the importance of the portosystemic shunt. 34 subjects have been studied. The ratio of heart to liver activity at the 25th minute after the tracer administration is higher in patients with liver cirrhosis (n=22, m=.9, s.d.=.37) than in patients with steatosis (n=10, m=.28, s.d.=.03). In two healthy subjects investigated the H/L ratio was .27 and .30. The reproducibility of the test was evaluated in 8 subjects and showed a good reproducibility (mean of difference =.03, range=.01 to .07). Patients with esophageal varices had always a high H/L ratio while some patients with liver cirrhosis without esophageal varices had also high H/L ratio, probably due to the presence of intrahepatic shunt. The authors' results showed the value of this new non-traumatic test for detecting and quantifying extra- as well as intrahepatic portosystematic shunt.

  2. Transvenous retrograde portography for identification and characterization of portosystemic shunts in dogs.

    PubMed

    Miller, Matthew W; Fossum, Theresa W; Bahr, Anne M

    2002-12-01

    Transvenous retrograde portography for identification and characterization of portosystemic shunts in dogs A method for transvenous retrograde portography (TRP) in dogs suspected to have a portosystemic shunt (PSS) and results in 20 dogs are described. For TRP, dogs were anesthetized and positioned in left lateral recumbency A dual-lumen balloon-tipped catheter was inserted into the right jugular vein and advanced into the azygos vein. The balloon was inflated to occlude the azygos vein, and contrast material was injected during fluoroscopic evaluation. The catheter was then positioned in the caudal vena cava just cranial to the diaphragm. The balloon was again inflated to occlude the vena cava, and contrast material was again injected. Once a shunt was identified, selective catheterization was attempted with a guide wire and angled catheter. A PSS was identified in 18 of the 20 dogs. In 10 of the 18, the shunt vessel could be selectively catheterized, allowing measurement of portal pressures while the shunt was occluded with the balloon. In 1 dog, results of TRP were normal, but subsequent exploratory celiotomy revealed a single extrahepatic PSS, which was surgically attenuated. The other dog in which results of TRP were normal did not have a macroscopic PSS. In dogs suspected to have a PSS, TRP may be a useful adjunctive diagnostic test that is less invasive than operative mesenteric vein portography and allows measurement of portal pressures before and after temporary shunt occlusion. PMID:12479329

  3. Asymptomatic Intrahepatic Portosystemic Venous Shunt: To Treat or Not To Treat?

    PubMed

    Palvanov, Arkadiy; Marder, Ruth Leah; Siegel, David

    2016-09-01

    Intrahepatic portosystemic venous shunts (IPSVSs) are rare vascular malformations. They can be asymptomatic or present with various symptoms including encephalopathy. We present two cases of IPSVS, one involving a patient presenting with altered mental status and the other discovered incidentally. While there is no question that patients presenting with symptomatic IPSVS should undergo definitive treatment, there is no consensus regarding elective therapy for asymptomatic lesions. PMID:27574389

  4. Irreversible Electroporation of a Hepatocellular Carcinoma Lesion Adjacent to a Transjugular Intrahepatic Portosystemic Shunt Stent Graft

    PubMed Central

    Jung, Ernst Michael; Wohlgemuth, Walter A.; Trabold, Benedikt; Haimerl, Michael; Schreyer, Andreas; Stroszczynski, Christian; Wiggermann, Philipp

    2013-01-01

    We report in a 65-year-old man hepatocellular carcinoma adjacent to a transjugular intrahepatic portosystemic shunt stent-graft which was successfully treated with irreversible electroporation (IRE). IRE is a new non-thermal tissue ablation technique which uses electrical pulses to induce cell necrosis by irreversible membrane poration. IRE proved to be more advantageous in the ablation of perivascular tumor with little injury to the surrounding structures. PMID:24043975

  5. Late Intrahepatic Hematoma Complicating Transjugular Intrahepatic Portosystemic Shunt for Budd-Chiari Syndrome

    SciTech Connect

    Terreni, Natalia; Vangeli, Marcello; Raimondo, Maria Luisa; Tibballs, Jonathan M.; Patch, David; Burroughs, Andrew K.

    2007-09-15

    Late intrahepatic hematoma is a rare complication of the transjugular intrahepatic portosystemic shunt (TIPS) procedure. We describe a patient with Budd-Chiari syndrome (BCS), who presented with a large inrahepatic hematoma 13 days after TIPS. Review of the literature reveals only two previous cases, both occurring in patients with BCS and presenting after a similar time interval. This potentially serious complication appears to be specific for TIPS in BCS.

  6. Portosystemic shunting in portal hypertension: evaluation with portal scintigraphy with transrectally administered I-123 IMP

    SciTech Connect

    Kashiwagi, T.; Azuma, M.; Ikawa, T.; Takehara, T.; Matsuda, H.; Yoshioka, H.; Mitsutani, N.; Koizumi, T.; Kimura, K.

    1988-10-01

    Portosystemic shunting was evaluated with rectal administration of iodine-123 iodoamphetamine (IMP) in seven patients without liver disease and 53 patients with liver cirrhosis. IMP (2-3 mCi (74-111 MBq)) was administered to the rectum through a catheter. Images of the chest and abdomen were obtained for up to 60 minutes with a scintillation camera interfaced with a computer. In all patients, images of the liver and/or lungs were observed within 5-10 minutes and became clear with time. In patients without liver disease, only liver images could be obtained, whereas the lung was visualized with or without the liver in all patients with liver cirrhosis. The portosystemic shunt index was calculated by dividing counts of lungs by counts of liver and lung. These values were significantly higher in liver cirrhosis, especially in the decompensated stage. Transrectal portal scintigraphy with IMP appears to be a useful method for noninvasive and quantitative evaluation of portosystemic shunting in portal hypertension.

  7. Pancreaticoportal Fistula and Disseminated Fat Necrosis After Revision of a Transjugular Intrahepatic Portosystemic Shunt

    SciTech Connect

    Klein, Seth J. Saad, Nael; Korenblat, Kevin; Darcy, Michael D.

    2013-04-15

    A 59-year old man with alcohol related cirrhosis and portal hypertension was referred for transjugular intrahepatic portosystemic shunt (TIPS) to treat his refractory ascites. Ten years later, two sequential TIPS revisions were performed for shunt stenosis and recurrent ascites. After these revisions, he returned with increased serum pancreatic enzyme levels and disseminated superficial fat necrosis; an iatrogenic pancreaticoportal vein fistula caused by disruption of the pancreatic duct was suspected. The bare area of the TIPS was subsequently lined with a covered stent-graft, and serum enzyme levels returned to baseline. In the interval follow-up period, the patient has clinically improved.

  8. Resolution of severe hepato-pulmonary syndrome following transjugular portosystemic shunt procedure

    PubMed Central

    Wallace, Michael C; James, Alan L; Marshall, Martin; Kontorinis, Nickolas

    2012-01-01

    The hepato-pulmonary syndrome (HPS) is a relatively common complication of hepatic disease that leads to hypoxaemia and dyspnoea secondary to pulmonary shunting. A number of pharmacological therapies have been trialled, yet liver transplantation remains the only definitive treatment. The use of a transjugular intrahepatic portosystemic shunt (TIPS) to reduce portal hypertension and improve oxygenation remains controversial in HPS due to the lack of large clinical series or randomised controlled trials. We present a case of HPS successfully treated with TIPS and review the relevant literature. PMID:22669921

  9. Resolution of severe hepato-pulmonary syndrome following transjugular portosystemic shunt procedure.

    PubMed

    Wallace, Michael C; James, Alan L; Marshall, Martin; Kontorinis, Nickolas

    2012-01-01

    The hepato-pulmonary syndrome (HPS) is a relatively common complication of hepatic disease that leads to hypoxaemia and dyspnoea secondary to pulmonary shunting. A number of pharmacological therapies have been trialled, yet liver transplantation remains the only definitive treatment. The use of a transjugular intrahepatic portosystemic shunt (TIPS) to reduce portal hypertension and improve oxygenation remains controversial in HPS due to the lack of large clinical series or randomised controlled trials. We present a case of HPS successfully treated with TIPS and review the relevant literature. PMID:22669921

  10. Scintigraphic evaluation of hepatic blood flow after intrahepatic portosystemic shunt (TIPS).

    PubMed

    Menzel, J; Schober, O; Reimer, P; Domschke, W

    1997-06-01

    In patients with liver cirrhosis a transjugularly placed intrahepatic portocaval shunt (TIPS) is a non-surgical portosystemic device which aims to reduce portal venous pressure. In comparison with Doppler sonography, we evaluated in 28 patients the diagnostic impact of liver perfusion scintigraphy (with technetium-99m diethylene triamine penta-acetic acid) in the assessment of changes in the hepatic blood flow after TIPS shunting. The arterial and portal contributions to hepatic flow were calculated from the areas under the biphasic time-activity curve. In the course of TIPS shunting, patency is threatened by reocclusion. Angiography is the gold standard for TIPS shunt reassessment. However, there is a need for a less invasive diagnostic procedure, such as scintigraphy or Doppler sonography, for the early detection of shunt insufficiency. Scintigraphy demonstrated that prior to TIPS shunting the portal venous contribution to hepatic perfusion was reduced to 29.2%, this reduction being due to portal hypertension. After TIPS placement a significant increase in portal venous perfusion was observed (38.2%; P<0.02). TIPS shunt occlusion was identified in patients by a significant reduction in the scintigraphically measured portal venous contribution to hepatic blood flow. Hepatic perfusion scintigraphy appears to be a valuable method to determine the immediate effect of TIPS on hepatic blood flow. Post-TIPS follow-up studies of hepatic haemodynamics by liver perfusion scintigraphy appear able to contribute to the detection of TIPS shunt occlusion before the clinical consequences of this complication have become apparent. PMID:9169570

  11. Symptomatic hepatic hydrothorax successfully treated with transjugular intrahepatic portosystemic shunt (TIPS)–role of titration of portosystemic gradient reduction to avoid post-TIPS encephalopathy

    PubMed Central

    Krishnamoorthy, T L; Taneja, M; Chang, P E

    2014-01-01

    Key Clinical Message We describe a challenging case of hepatic hydrothorax secondary to nonalcoholic steatohepatitis cirrhosis. Our management involved successfully treating the hydrothorax with a transjugular intrahepatic porto-systemic shunt but having to manage the subsequent complication of hepatic encephalopathy. We conclude with a review of the available literature. PMID:25356258

  12. Transjugular intrahepatic portosystemic shunt combined with esophagogastric variceal embolization in the treatment of a large gastrorenal shunt

    PubMed Central

    Jiang, Qin; Wang, Ming-Quan; Zhang, Guo-Bing; Wu, Qiong; Xu, Jian-Ming; Kong, De-Run

    2016-01-01

    AIM: To evaluate the efficacy and safety of transjugular intrahepatic portosystemic shunt (TIPS) combined with stomach and esophageal variceal embolization (SEVE) in cirrhotic patients with a large gastrorenal vessel shunt (GRVS). METHODS: Eighty-one cirrhotic patients with gastric variceal bleeding (GVB) associated with a GRVS were enrolled in the study and accepted TIPS combined with SEVE (TIPS + SEVE), by which portosystemic pressure gradient (PPG), biochemical, TIPS-related complications, shunt dysfunction, rebleeding, and death were evaluated. RESULTS: The PPGs before TIPS were greater than 12 mmHg in 81 patients. TIPS + SEVE treatment caused a significant decrease in PPG (from 37.97 ± 6.36 mmHg to 28.15 ± 6.52 mmHg, t = 19.22, P < 0.001). The percentage of reduction in PPG was greater than 20% from baseline. There were no significant differences in albumin, alanine aminotransferase, aspartate aminotransferase, bilirubin, prothrombin time, or Child-Pugh score before and after operation. In all patients, rebleeding rates were 3%, 6%, 12%, 18%, and 18% at 1, 3, 6, 12, and 18 mo, respectively. Five patients (6.2%) were diagnosed as having hepatic encephalopathy. The rates of shunt dysfunction were 0%, 4%, 9%, 26%, and 26%, at 1, 3, 6, 12, and 18 mo, respectively. The cumulative survival rates in 1, 3, 6, 12, and 18 mo were 100%, 100%, 95%, 90%, and 90%, respectively. CONCLUSION: Our preliminary results indicated that the efficacy and safety of TIPS + SEVE were satisfactory in cirrhotic patients with GVB associated with a GRVS (GVB + GRVS). PMID:27458505

  13. The history and future of transjugular intrahepatic portosystemic shunt: food for thought.

    PubMed

    Saad, Wael E

    2014-09-01

    The origins of transjugular intrahepatic portosystemic shunt (TIPS) date back to the 1960s with inadvertent portal access during the early years of transjugular cholangiography. TIPS is now the most frequently performed portal hypertension decompressive procedure performed by interventional radiologists, and has become the primary portosystemic shunt (surgical or percutaneous) performed in the United States. One of the least discussed major advantages of TIPS in the transplant era is that it is intrahepatic and thus is removed in situ during a liver transplant, while extrahepatic shunts (surgical or percutaneous) have to be ligated or revised during the liver transplantation. However, since the widespread clinical utilization of TIPS in the 1990s, it has been plagued with two major problems, namely, patency and hepatic encephalopathy. With the advent of commercially available expanded polytetraflouroethylenne (e-PTFE) covered stents a decade ago, 12- to 24-month TIPS patency has improved significantly (by ∼20-30%). However, hepatic encephalopathy (although not proven to have increased due to e-PTFE covered stents grafts) remains a significant morbidity problem. The article discusses the history of TIPS, critiques the retrospective encephalopathy data in the literature, and discusses futuristic TIPS-design ideas about the management of post-TIPS hepatic encephalopathy. PMID:25177087

  14. Staged Transcatheter Treatment of Portal Hypoplasia and Congenital Portosystemic Shunts in Children

    SciTech Connect

    Bruckheimer, Elchanan Dagan, Tamir; Atar, Eli; Schwartz, Michael; Kachko, Ludmila; Superina, Riccardo; Amir, Gabriel; Shapiro, Rivka; Birk, Einat

    2013-12-15

    Purpose: Congenital portosystemic shunts (CPSS) with portal venous hypoplasia cause hyperammonemia. Acute shunt closure results in portal hypertension. A transcatheter method of staged shunt reduction to afford growth of portal vessels followed by shunt closure is reported. Methods: Pressure measurements and angiography in the CPSS or superior mesenteric artery (SMA) during temporary occlusion of the shunt were performed. If vessels were diminutive and the pressure was above 18 mmHg, a staged approach was performed, which included implantation of a tailored reducing stent to reduce shunt diameter by {approx}50 %. Recatheterization was performed approximately 3 months later. If the portal pressure was below 18 mmHg and vessels had developed, the shunt was closed with a device. Results: Six patients (5 boys, 1 girl) with a median age of 3.3 (range 0.5-13) years had CPSS portal venous hypoplasia and hyperammonemia. Five patients underwent staged closure. One patient tolerated acute closure. One patient required surgical shunt banding because a reducing stent could not be positioned. At median follow-up of 3.8 (range 2.2-8.4) years, a total of 21 procedures (20 transcatheter, 1 surgical) were performed. In all patients, the shunt was closed with a significant reduction in portal pressure (27.7 {+-} 11.3 to 10.8 {+-} 1.8 mmHg; p = 0.016), significant growth of the portal vessels (0.8 {+-} 0.5 to 4.0 {+-} 2.4 mm; p = 0.037), and normalization of ammonia levels (202.1 {+-} 53.6 to 65.7 {+-} 9.6 {mu}mol/L; p = 0.002) with no complications. Conclusion: Staged CPSS closure is effective in causing portal vessel growth and treating hyperammonemia.

  15. Rectal variceal bleeding treated by transjugular intrahepatic portosystemic shunt. Potentials and pitfalls.

    PubMed

    Godil, A; McCracken, J D

    1997-09-01

    Bleeding from anorectal varices can be massive and life threatening. Prompt differentiation between hemorrhoids and anorectal varices is crucial in treating these patients. Many different treatments are available for bleeding anorectal varices, but none has proved efficacy. We report a case of successful transjugular intrahepatic portosystemic shunt (TIPS) in controlling massive rectal variceal bleeding in an elderly patient with primary biliary cirrhosis and portal hypertension. After TIPS, rapid decompensation of liver function and encephalopathy developed and led to her death. Although TIPS may be effective in controlling acute life-threatening bleeding from anorectal varices, it can be associated with life-threatening complications. PMID:9412951

  16. The brain following transjugular intrahepatic portosystemic shunt: the perspective from neuroimaging.

    PubMed

    Chen, Hui Juan; Zheng, Gang; Wichmann, Julian L; Schoepf, U Joseph; Lu, Guang Ming; Zhang, Long Jiang

    2015-12-01

    Hepatic encephalopathy (HE) is a common complication after implantation of a transjugular intrahepatic portosystemic shunt (TIPS). Neuroimaging offers a variety of techniques for non-invasive evaluation of alterations in metabolism, as well as structural and functional changes of the brain in patients after TIPS implantation. In this article, we review the epidemiology and pathophysiology of post-TIPS HE. The potential of neuroimaging including positron emission tomography and multimodality magnetic resonance imaging to investigate the pathophysiology of post-TIPS HE is presented. We also give a perspective on the role of neuroimaging in this field. PMID:26404041

  17. Hepatic Veins and Inferior Vena Cava Thrombosis in a Child Treated by Transjugular Intrahepatic Portosystemic Shunt

    SciTech Connect

    Carnevale, Francisco Cesar Santos, Aline Cristine Barbosa; Tannuri, Uenis; Cerri, Giovanni Guido

    2010-06-15

    We report the case of a 9-year-old boy with portal hypertension, due to Budd-Chiari syndrome, and retrohepatic inferior vena cava thrombosis, submitted to a transjugular intrahepatic portosystemic shunt (TIPS) by connecting the suprahepatic segment of the inferior vena cava directly to the portal vein. After 3 months, the withdrawal of anticoagulants promoted the thrombosis of the TIPS. At TIPS revision, thrombosis of the TIPS and the main portal vein and clots at the splenic and the superior mesenteric veins were found. Successful angiography treatment was performed by thrombolysis and balloon angioplasty of a severe stenosis at the distal edge of the stent.

  18. Hepatic Encephalopathy after Transjugular Intrahepatic Portosystemic Shunt in Patients with Recurrent Variceal Hemorrhage

    PubMed Central

    Peter, Popovič; Andrej, Zore; Katarina, Šurlan Popovič; Manca, Garbajs; Pavel, Skok

    2013-01-01

    Purpose. The purpose of this study was to determine the incidence and predictors of hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS) and endoscopic therapy (ET) in the elective treatment of recurrent variceal hemorrhage. Methods. Seventy patients were treated with elective TIPS and fifty-six patients with ET. Median observation time was 46.28 months in the TIPS group and 42.31 months in the ET group. Results. 30 patients (42.8%) developed clinically evident portosystemic encephalopathy in TIPS group and 20 patients (35.6%) in ET group. The difference between the groups was not statistically significant (P = 0.542; χ2 test). The incidence of new or worsening portosystemic encephalopathy was 24.3% in TIPS group and 10.7% in ET group. Multivariate analysis showed that ET treatment (P = 0.031), age of >65 years (P = 0.022), pre-existing HE (P = 0.045), and Child's class C (P = 0.051) values were independent predictors for the occurrence of HE. Conclusions. Procedure-related HE is a complication in a minority of patients treated with TIPS or ET. Patients with increased age, preexisting HE, and higher Child-Pugh score should be carefully observed after TIPS procedure because the risk of post-TIPS HE in these patients is higher. PMID:23606833

  19. Efficacy of Doppler Ultrasonography for Assessment of Transjugular Intrahepatic Portosystemic Shunt Patency

    SciTech Connect

    Kimura, Masashi; Sato, Morio; Kawai, Nobuyuki; Tanaka, Kayo; Sonomura, Tetsuo; Shioyama, Kazushi; Kishi, Yasukazu; Terada, Masaki; Yamada, Ryusaku

    1996-11-15

    Purpose: To assess the efficacy of Doppler ultrasonography (US) as a noninvasive method for monitoring patency of the transjugular intrahepatic portosystemic shunt (TIPS). Methods: Twenty-nine patients who had received TIPS for bleeding esophagogastric varices and/or refractory ascites with portal hypertension underwent Doppler US studies within 2 weeks after TIPS. Further studies were performed in 15 of them at 6 months, in 9 at 1 year, and in 4 at 2 years for a total of 57 US studies. The US findings were compared with the angiographic findings obtained at the same time. Results: In 45 of the 57 studies, shunt patency was found by Doppler US, correlating to 44 patencies and one occlusion on angiography. Doppler signal in the shunt could not be detected in 12 studies resulting in the diagnosis of shunt occlusion. This correlated with angiographic occlusion in 8 studies and patency in the remaining 4. All angiographically patent shunts that were occluded by Doppler US had various degrees of stenosis. A number of technical factors were found to be responsible for Doppler US false-positive or false-negative diagnoses, some related to the type of stent used. The Doppler US sensitivity was therefore 92%, the specificity 89%. Conclusion: Doppler US is a reliable noninvasive method to evaluate patency of TIPS.

  20. Congenital Extrahepatic Portosystemic Shunts: Spectrum of Findings on Ultrasound, Computed Tomography, and Magnetic Resonance Imaging

    PubMed Central

    Gupta, Pankaj; Sinha, Anindita; Sodhi, Kushaljit Singh; Lal, Anupam; Debi, Uma; Thapa, Babu R.; Khandelwal, Niranjan

    2015-01-01

    Congenital extrahepatic portosystemic shunt (CEPS) is a rare disorder characterised by partial or complete diversion of portomesenteric blood into systemic veins via congenital shunts. Type I is characterised by complete lack of intrahepatic portal venous blood flow due to an end to side fistula between main portal vein and the inferior vena cava. Type II on the other hand is characterised by partial preservation of portal blood supply to liver and side to side fistula between main portal vein or its branches and mesenteric, splenic, gastric, and systemic veins. The presentation of these patients is variable. Focal liver lesions, most commonly nodular regenerative hyperplasia, are an important clue to the underlying condition. This pictorial essay covers imaging characteristics in abdominopelvic region. PMID:26858845

  1. Noncirrhotic Extrahepatic Portosystemic Shunt Causing Adult-Onset Encephalopathy Treated with Endovascular Closure

    PubMed Central

    Elnekave, Eldad; Belenky, Eugenia; Van der Veer, Lindsley

    2015-01-01

    A 54-year-old woman presented with a six-month history of episodic confusion and progressive ataxia. A comprehensive metabolic panel was notable for elevated values of alkaline phosphatase (161 U/L), total bilirubin (1.5 mg/dL), and serum ammonia of 300 umol/L (normal range 9–47). Hepatitis panel, relevant serological tests, tumor markers (CA-19-9, CEA), and urea cycle enzyme studies were unrevealing. Lactulose and rifaximin therapy failed to normalize serum ammonia levels. Imaging revealed a structural vascular abnormality communicating between an enlarged inferior mesenteric vein and the left renal vein, measuring 16 mm in greatest diameter. The diagnosis of congenital extrahepatic portosystemic shunt was made and endovascular shunt closure was performed using a 22 mm Amplatzer II vascular plug. Within a day, serum ammonia levels normalized. Lactulose and rifaximin were discontinued, and confusion and ataxia resolved. PMID:26199783

  2. Transjugular intrahepatic portosystemic shunt using the FLUENCY expanded polytetrafluoroethylene-covered stent.

    PubMed

    Wu, Qinghua; Jiang, Jianwei; He, Yujie; Jiang, Tianpeng; Zhou, Shi

    2013-01-01

    The aim of this study was to evaluate the feasibility of transjugular intrahepatic portosystemic shunts using FLUENCY expanded polytetraf luoroethylene (PTFE)-covered stents and the effect on the patency rate. A total of 114 cirrhotic patients who were treated by transjugular intrahepatic portosystemic stent shunt (TIPS) placement using a FLUENCY expanded, PTFE-covered stent were enrolled in the present study. Of the patients, 15 underwent an additional bare metal stent implantation on the portal side of the covered stent, simultaneously. Patients underwent Doppler sonography during the follow-up. Mean portal venous pressure dropped from 2.499±0.588 cmHg to 1.764±0.294 cmHg. The cumulative patency rates for one and two years were 86.7% and 75.2%, respectively. The results demonstrate the feasibility of TIPS placement with the FLUENCY expanded PTFE-covered stent. TIPS placement with the FLUENCY expanded PTFE-covered stent was able to improve patency when compared with the use of conventional bare-metal stents. PMID:23251280

  3. Transjugular Intrahepatic Portosystemic Shunt Placement in Patients with Cirrhosis and Concomitant Portal Vein Thrombosis

    SciTech Connect

    Ha, Thuong G. Van Hodge, Justin; Funaki, Brian; Lorenz, Jonathan; Rosenblum, Jordan; Straus, Christopher; Leef, Jeff

    2006-10-15

    Purpose. To determine the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) creation in patients with liver cirrhosis complicated by thrombosed portal vein. Methods. This study reviewed 15 cases of TIPS creation in 15 cirrhotic patients with portal vein thrombosis at our institution over an 8-year period. There were 2 women and 13 men with a mean age of 53 years. Indications were refractory ascites, variceal hemorrhage, and refractory pleural effusion. Clinical follow-up was performed in all patients. Results. The technical success rate was 75% (3/4) in patients with chronic portal vein thrombosis associated with cavernomatous transformation and 91% (10/11) in patients with acute thrombosis or partial thrombosis, giving an overall success rate of 87%. Complications included postprocedural encephalopathy and localized hematoma at the access site. In patients with successful shunt placement, the total follow-up time was 223 months. The 30-day mortality rate was 13%. Two patients underwent liver transplantation at 35 days and 7 months, respectively, after TIPS insertion. One patient had an occluded shunt at 4 months with an unsuccessful revision. The remaining patients had functioning shunts at follow-up. Conclusion. TIPS creation in thrombosed portal vein is possible and might be a treatment option in certain patients.

  4. Hepatic Encephalopathy Secondary to Intrahepatic Portosystemic Venous Shunt: Balloon-Occluded Retrograde Transvenous Embolization with n-Butyl Cyanoacrylate and Microcoils

    SciTech Connect

    Yamagami, Takuji; Nakamura, Toshiyuki; Iida, Shigeharu; Kato, Takeharu; Tanaka, Osamu; Matsushima, Shigenori; Ito, Hirotoshi; Okuyama, Chio; Ushijima, Yo; Shiga, Kensuke; Nishimura, Tsunehiko

    2002-06-15

    We report a 70-year-old woman with hepatic encephalopathy due to an intrahepatic portosystemic venous shunt that was successfully occluded by percutaneous transcatheter embolization with n-butyl cyanoacrylate and microcoils.

  5. Potential Pitfalls in Transjugular Portosystemic Shunt Placement for Bleeding Rectal Varices

    PubMed Central

    Sakib, S M Nazmus; Kobayashi, Katsuhiro; Jawed, Mohammed

    2015-01-01

    In patients with portal hypertension, bleeding from rectal varices is rare. However, it can be life-threatening. We report a case of massive bleeding from large rectal varices in a 59-year-old man with alcoholic cirrhosis. Emergent transjugular intrahepatic portosystemic shunt (TIPS) placement was performed following failed local endoscopic therapy. Despite normalization of the portosystemic pressure gradient, the patient had another episode of massive bleeding on the following day. Embolization of the rectal varices via TIPS successfully stopped the bleeding. After the procedure, rapid decompensation of the cirrhosis led to severe encephalopathy, and death was observed. Although TIPSs have been reported to be useful in controlling bleeding from rectal varices, our case illustrates the potential pitfalls in using this technique in the treatment of rectal variceal bleeding. TIPSs may not be always successful in controlling massive bleeding from large rectal varices, even after normalization of portal hypertension. TIPSs can also be associated with life-threatening complications that may lead to early mortality. PMID:26464566

  6. Severe liver fibrosis caused by Schistosoma mansoni: management and treatment with a transjugular intrahepatic portosystemic shunt.

    PubMed

    Richter, Joachim; Bode, Johannes G; Blondin, Dirk; Kircheis, Gerald; Kubitz, Ralf; Holtfreter, Martha C; Müller-Stöver, Irmela; Breuer, Matthias; Hüttig, Falk; Antoch, Gerald; Häussinger, Dieter

    2015-06-01

    Liver diseases are common in inhabitants and migrants of tropical countries, where the liver can be exposed not only to toxins but also to many viral, bacterial, fungal, and parasitic infections. Schistosomiasis--a common parasitic infection that affects at least 240 million people worldwide, mostly in Africa--is regarded as the most frequent cause of liver fibrosis worldwide. We present a case of a 19-year-old male refugee from Guinea with recurrent oesophageal variceal bleeding due to schistosomal liver fibrosis refractory to endoscopic therapy. This case was an indication for portosystemic surgery, which is a highly invasive non-reversible intervention. An alternative, less invasive, reversible radiological procedure, used in liver cirrhosis, is the placement of a transjugular intrahepatic portosystemic shunt (TIPS). After thorough considerations of all therapeutic options we placed a TIPS in our patient. In more than 3 years of observation, he is clinically well apart from one episode of hepatic encephalopathy related to an acute episode of viral gastroenteritis. Bleeding from oesophageal varices has not recurred. In this Grand Round, we review the diagnostic approaches and treatment options for portal hypertension due to schistosomal liver fibrosis. PMID:25769268

  7. A new nitinol monofilament stent: early experience with use for transjugular intrahepatic portosystemic shunts.

    PubMed

    Yoon, Chang Jin; Chung, Jin Wook; Kim, Hyun Beom; Lee, Joon Woo; Park, Jae Hyung

    2002-01-01

    The purpose of this study was to investigate the suitability of a new nitinol monofilament stent (Niti-S) for transjugular intrahepatic portosystemic shunt (TIPS) creation. TIPS was performed with a Niti-S stent in 22 patients for variceal bleeding (n = 20) or intractable ascites (n = 2). The efficacy, complication, and patency rates during the follow-up period (up to 27 months, mean 13.9 months) were evaluated. TIPS was successfully performed in all patients. The mean portosystemic pressure gradient decreased from 23.8 +/- 7.2 mmHg to 10.2 +/- 3.1 mmHg. No mortality or significant morbidity was encountered at 1 month. Variceal bleeding and/or ascites were controlled in all patients. Primary patency rates were 77.3% at 6 months and 71.8% at 1 year. Secondary patency rates were 95.4% up to 26 months. TIPS with the Niti-S stent produced short-term technical and clinical results comparable to the other commercially available stents. A prospective randomized comparison study is indicated. PMID:12058215

  8. Self-expanding stents in transjugular intrahepatic portosystemic shunt: experience with nitinol Strecker stents.

    PubMed

    Rossi, P; Bezzi, M; Salvatori, F M; Broglia, L; Maccioni, F; Pizzi, G; Abbondanza, S; Bonomo, G

    1996-01-01

    The aim of our study was to evaluate the performance and efficacy of a new self-expanding stent (nitinol Strecker stent) in the transjugular intrahepatic portosystemic shunt (TIPS) procedure. We have successfully placed 64 nitinol Strecker stents in 48 patients. The average portosystemic gradient decreased from 22 to 11 mm Hg. Balloon dilatation was necessary in 12 of 35 angiographically controlled cases at 5 days (34%), because of incomplete stent expansion, small thrombi within the stent or obstruction. At 1-6 months stent malfunctions occurred in 8 of 23 patients who underwent control angiography (34%) and at 6-24 months in 6 of 7 patients (85%). Rebleeding occurred in 2 of 39 patients (follow-up > 1 month) (5%) and temporary crises of de novo encephalopathy were observed in 11 of 48 patients (23%). Refractory ascites completely resolved in 4 of 6 patients (66%) and improved in the remaining 2 cases. Compared with other self-expanding stents, nitinol Strecker stents seem to be equally effective in TIPS; no increase in complication rate was observed, either clinical or stent-related. PMID:8934143

  9. Could there be light at the end of the tunnel? Mesocaval shunting for refractory esophageal varices in patients with contraindications to transjugular intrahepatic portosystemic shunt

    PubMed Central

    Davis, Jessica; Chun, Albert K; Borum, Marie L

    2016-01-01

    Cirrhotic patients with recurrent variceal bleeds who have failed prior medical and endoscopic therapies and are not transjugular intrahepatic portosystemic shunt candidates face a grim prognosis with limited options. We propose that mesocaval shunting be offered to this group of patients as it has the potential to decrease portal pressures and thus decrease the risk of recurrent variceal bleeding. Mesocaval shunts are stent grafts placed by interventional radiologists between the mesenteric system, most often the superior mesenteric vein, and the inferior vena cava. This allows flow to bypass the congested hepatic system, reducing portal pressures. This technique avoids the general anesthesia and morbidity associated with surgical shunt placement and has been successful in several case reports. In this paper we review the technique, candidate selection, potential pitfalls and benefits of mesocaval shunt placement. PMID:27429715

  10. Transjugular Intrahepatic Portosystemic Shunt (TIPS) Migration to the Heart Diagnosed by Emergency Department Ultrasound.

    PubMed

    Wendler, Carlan; Shoenberger, Jan Marie; Mailhot, Thomas; Perera, Phillips

    2012-12-01

    A 57-year-old man presented to our emergency department with altered mental status. He had a past medical history significant for cirrhosis and previous placement of a transjugular intrahepatic portosystemic shunt (TIPS). On cardiac auscultation, a new heart murmur and an unexpected degree of cardiac ectopy were noted. On the 12-lead electrocardiogram, the patient was noted to have multiple premature atrial contractions, corroborating the irregular heart rhythm on physical exam. A focused bedside emergency ultrasound of the heart was then performed. This exam revealed an apparent foreign body in the right atrium. It appeared as if the patient's TIPS had migrated from the heart into the right atrium. This case, as well as the literature describing this unusual complication of TIPS placement, is reviewed in this case report. PMID:23358693

  11. Transjugular Intrahepatic Portosystemic Shunt in a Patient with Cavernomatous Portal Vein Occlusion

    SciTech Connect

    Kawamata, Hiroshi; Kumazaki, Tatsuo; Kanazawa, Hidenori; Takahashi, Shuji; Tajima, Hiroyuki; Hayashi, Hiromitsu

    2000-03-15

    A 23-year-old woman with liver cirrhosis secondary to primary sclerosing cholangitis was referred to us for the treatment of recurrent bleeding from esophageal varices that had been refractory to endoscopic sclerotherapy. Her portal vein was occluded, associated with cavernous transformation. A transjugular intrahepatic portosystemic shunt (TIPS) was performed after a preprocedural three-dimensional computed tomographic angiography evaluation to determine feasibility. The portal vein system was recanalized and portal blood flow increased markedly after TIPS. Esophageal varices disappeared 3 weeks after TIPS. Re-bleeding and hepatic encephalopathy were absent for 3 years after the procedure. We conclude that with adequate preprocedural evaluation, TIPS can be performed safely even in patients with portal vein occlusion associated with cavernous transformation.

  12. Transjugular Intrahepatic Portosystemic Shunt: Indications, Contraindications, and Patient Work-Up

    PubMed Central

    Copelan, Alexander; Kapoor, Baljendra; Sands, Mark

    2014-01-01

    The transjugular intrahepatic portosystemic shunt (TIPS) procedure is effective in achieving portal decompression and in managing some of the major complications of portal hypertension. While many clinicians are familiar with the two most common indications for TIPS placement, secondary prophylaxis of esophageal variceal hemorrhage and treatment of refractory ascites, evidence for its usefulness is growing in other entities, where it has been less extensively studied but demonstrates promising results. Newer indications include early utilization in the treatment of esophageal variceal hemorrhage, Budd–Chiari syndrome, ectopic varices, and portal vein thrombosis. The referring clinician and interventionist must remain cognizant of the contraindications to the procedure to avoid complications and potential harm to the patient. This review is designed to provide an in-depth analysis of the most common as well as less typical indications for TIPS placement, and to discuss the contraindications and appropriate patient evaluation for this procedure. PMID:25177083

  13. Delayed liver laceration following transjugular intrahepatic portosystemic shunt for portal hypertension

    PubMed Central

    Liu, Kai; Fan, Xin-Xin; Wang, Xu-Lin; He, Chang-Sheng; Wu, Xing-Jiang

    2012-01-01

    The transjugular intrahepatic portosystemic shunt (TIPS) is an acceptable procedure that has proven benefits in the treatment of patients who have complications from portal hypertension due to liver cirrhosis. Delayed liver laceration is a rare complication of the TIPS procedure. We describe a patient with portal hypertension due to liver cirrhosis, who suddenly presented with abdominal hemorrhage and liver laceration 8 d after TIPS. Few reports have described complications after TIPS placement. To the best of our knowledge, this is the first report describing delayed liver laceration. This potential and serious complication appears to be specific and fatal for TIPS in portal hypertension. We advocate careful attention to the technique to avoid this complication, and timely treatment is extremely important. PMID:23326153

  14. Delayed liver laceration following transjugular intrahepatic portosystemic shunt for portal hypertension.

    PubMed

    Liu, Kai; Fan, Xin-Xin; Wang, Xu-Lin; He, Chang-Sheng; Wu, Xing-Jiang

    2012-12-28

    The transjugular intrahepatic portosystemic shunt (TIPS) is an acceptable procedure that has proven benefits in the treatment of patients who have complications from portal hypertension due to liver cirrhosis. Delayed liver laceration is a rare complication of the TIPS procedure. We describe a patient with portal hypertension due to liver cirrhosis, who suddenly presented with abdominal hemorrhage and liver laceration 8 d after TIPS. Few reports have described complications after TIPS placement. To the best of our knowledge, this is the first report describing delayed liver laceration. This potential and serious complication appears to be specific and fatal for TIPS in portal hypertension. We advocate careful attention to the technique to avoid this complication, and timely treatment is extremely important. PMID:23326153

  15. A Glasgow Tipple—transjugular intrahepatic portosystemic shunt insertion prior to Whipple resection

    PubMed Central

    Jabbar, Salman A.A.; Jamieson, Nigel B.; Morris, Andrew J.; Oien, Karin A.; Duthie, Fraser; McKay, Colin J.; Carter, Christopher R.; Dickson, Euan J.

    2016-01-01

    Abdominal surgery performed in patients with significant liver disease and portal hypertension is associated with high mortality rates, with even poorer outcomes associated with complex pancreaticobiliary operations. We report on a patient requiring portal decompression via transjugular intrahepatic portosystemic shunt (TIPS) prior to a pancreaticoduodenectomy. The 49-year-old patient presented with pain, jaundice and weight loss. At ERCP an edematous ampulla was biopsied, revealing high-grade dysplasia within a distal bile duct adenoma. Liver biopsy was performed to investigate portal hypertension, confirming congenital hepatic fibrosis (CHF). A TIPS was performed to enable a pancreaticoduodenectomy. Prophylactic TIPS can be performed for preoperative portal decompression for patients requiring pancreatic resection. A potentially curative resection was performed when abdominal surgery was initially thought impossible. Notably, CHF has been associated with the development of cholangiocarcinoma in only four previous instances, with this case being only the second reported distal bile duct cholangiocarcinoma. PMID:27177892

  16. Usefulness of Transjugular Intrahepatic Portosystemic Shunt in the Management of Bleeding Ectopic Varices in Cirrhotic Patients

    SciTech Connect

    Vidal, V.; Joly, L.; Perreault, P.; Bouchard, L.; Lafortune, M.; Pomier-Layrargues, G.

    2006-04-15

    Purpose. To evaluate the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) in the control of bleeding from ectopic varices. Methods. From 1995 to 2004, 24 cirrhotic patients, bleeding from ectopic varices, mean age 54.5 years (range 15-76 years), were treated by TIPS. The etiology of cirrhosis was alcoholic in 13 patients and nonalcoholic in 11 patients. The location of the varices was duodenal (n = 5), stomal (n = 8), ileocolic (n = 6), anorectal (n = 3), umbilical (n = 1), and peritoneal (n 1). Results. TIPS controlled the bleeding in all patients and induced a decrease in the portacaval gradient from 19.7 {+-} 5.4 to 6.4 {+-} 3.1 mmHg. Postoperative complications included self-limited intra-abdominal bleeding (n = 2), self-limited hemobilia (n = 1), acute thrombosis of the shunt (n = 1), and bile leak treated by a covered stent (n = 1). Median follow-up was 592 days (range 28-2482 days). Rebleeding occurred in 6 patients. In 2 cases rebleeding was observed despite a post-TIPS portacaval gradient lower than 12 mmHg and was controlled by variceal embolization; 1 patient underwent surgical portacaval shunt and never rebled; in 3 patients rebleeding was related to TIPS stenosis and treated with shunt dilatation with addition of a new stent. The cumulative rate of rebleeding was 23% and 31% at 1 and 2 years, respectively. One- and 2-year survival rates were 80% and 76%, respectively. Conclusion. The present series demonstrates that bleeding from ectopic varices, a challenging clinical problem, can be managed safely by TIPS placement with low rebleeding and good survival rates.

  17. Intravascular Ultrasound Guidance for Transjugular Intrahepatic Portosystemic Shunt Procedure in a Swine Model

    SciTech Connect

    Kew, Jacqueline; Davies, Roger P.

    2004-01-15

    A new method is described for guiding hepato-portalvenous puncture using a longitudinal side-view intravascular ultrasound(L-IVUS) transducer to assist in the performance of transjugularintrahepatic portosystemic shunt (TIPS) in three Australian swine.Simultaneous L-IVUS with an AcuNav (registered) 5-10 MHz 10 Fr transducer(Acuson Corporation, Mountain View, CA, USA) and fluoroscopy guidance was used to image and monitor the hepatic to portal venous puncture,dilatation of the tract, and deployment of the TIPS stent. Flow through the shunt could be demonstrated with both L-IVUS and angiography. TIPS was successful in all swine. The time for portal vein puncture once the target portal vein was identified was reduced at each attempt. The number of portal vein puncture attempts was 2, 1, and 1. No post-procedural complication was evident. L-IVUS-guided TIPS is practical and has the potential to improve safety by permitting simultaneous ultrasound and fluoroscopic imaging of the needle and target vascular structures. This technique allows for a more streamlined approach to TIPS, decreasing the fluoroscopic time (hence,decreasing the radiation exposure to the staff and patient) and anesthetic time. In addition, there are improved safety benefits obviating the need for wedged portography, facilitating avoidance of bile duct and hepatic arterial puncture, and minimizing hepatic injury by decreasing liver capsular puncture and the attendant risks.

  18. Embolization of Portosystemic Shunts for Treatment of Medically Refractory Hepatic Encephalopathy

    PubMed Central

    Lynn, Amanda M.; Singh, Siddharth; Congly, Stephen E.; Khemani, Disha; Johnson, David H.; Wiesner, Russell H.; Kamath, Patrick S.; Andrews, James C.; Leise, Michael D.

    2016-01-01

    Treatment options for refractory hepatic encephalopathy (HE) are limited. Patients who fail medical management may harbor large portosystemic shunts (PSSs) which are possible therapeutic targets. This study aims to describe patient selection, effectiveness, and safety of percutaneous PSS embolization in those with medically refractory HE. A retrospective evaluation of consecutive adult patients with medically refractory HE referred for PSS embolization at a tertiary center was performed (2003–2015). Patient data collected included the type of HE, medications, Model for End-Stage Liver Disease (MELD) score, shunt type, embolization approach, and materials used. Outcomes of interest were immediate (7 days), intermediate (1–4 months), and longer-term (6–12 months) effectiveness and periprocedural safety. Effectiveness was determined based on changes in hospitalization frequency, HE medications, and symptoms. Twenty-five patients with large PSS were evaluated for shunt embolization. Five were excluded due to high MELD scores (n = 1), comorbid conditions (n = 1), or technical considerations (n = 3). Of 20 patients who underwent embolization, 13 had persistent and 7 had recurrent HE; 100% (20/20) achieved immediate improvement. Durable benefit was achieved in 100% (18/18) and 92% (11/12) at 1–4 and 6–12 months, respectively. The majority (67%; 8/12) were free from HE-related hospitalizations over 1 year; 10% developed procedural complications, and all resolved. Six developed new or worsening ascites. In conclusion, PSS embolization is a safe and effective treatment strategy that should be considered for select patients with medically refractory HE. PMID:26970243

  19. ePTFE-Covered Stent-Grafts for Revision of Obstructed Transjugular Intrahepatic Portosystemic Shunt

    SciTech Connect

    Cejna, Manfred; Peck-Radosavljevic, Markus; Thurnher, Siegfried; Schoder, Maria; Rand, Thomas; Angermayr, Bernhard; Lammer, Johannes

    2002-10-15

    Purpose: To determine whether transjugular intrahepatic portosystemic shunt (TIPS) revisions with the Hemobahn stent-graft or the Viatorr endoprosthesis increase secondary patency rates. Methods: Between 1998 and June 1999,Hemobahn endoprostheses (W.L. Gore, Flagstaff, AZ, USA) were used for the revision of obstructed TIPS in seven patients, 51-67 years of age(mean 59 years). From June 1999 to 2000, the Viatorr endoprosthesis(W.L. Gore, Flagstaff, AZ, USA) was used for revision of obstructed TIPS in nine patients, 33-64 years of age (mean 49 years). Follow-up included duplex ultrasound, clinical assessment and venousportography. Results: The technical success rate of TIPS revision with the Hemobahn stent-graft was 100%. The pressure gradient decreased from a mean of 20 mmHg to 10 mmHg. The mean follow-up was 407 days (range 81-868 days). In two patients TIPS occlusion occurred at 62 and 529 days after stent-graft placement, respectively; in another two patients outflow tract stenosis occurred at 275 and 393 days,respectively. The technical success rate of TIPS revision with the Viatorr endoprosthesis was also 100%. The pressure gradient decreased from a mean of 27 mmHg to 11 mmHg. At a mean follow-up of 201 days(range 9-426 days), all Viatorr endoprostheses are still patent without in-graft stenosis, but angioplasty was required in two patients to treat a portosystemic pressure gradient > 15 mmHg. Four of the nine patients in the Viatorr group suffered from new encephalopathy after TIPS revision. Conclusion: The Viatorrendoprosthesis yielded optimal results with 100% in-graft patency rates at follow-up but had a high incidence of new encephalopathy,whereas the use of Hemobahn stent-graft for TIPS revision did not appear to improve the secondary patency rates in our series.

  20. Combined transjugular intrahepatic portosystemic shunt and other interventions for hepatocellular carcinoma with portal hypertension

    PubMed Central

    Qiu, Bin; Zhao, Meng-Fei; Yue, Zhen-Dong; Zhao, Hong-Wei; Wang, Lei; Fan, Zhen-Hua; He, Fu-Liang; Dai, Shan; Yao, Jian-Nan; Liu, Fu-Quan

    2015-01-01

    AIM: To evaluate combination transjugular intrahepatic portosystemic shunt (TIPS) and other interventions for hepatocellular carcinoma (HCC) and portal hypertension. METHODS: Two hundred and sixty-one patients with HCC and portal hypertension underwent TIPS combined with other interventional treatments (transarterial chemoembolization/transarterial embolization, radiofrequency ablation, hepatic arterio-portal fistulas embolization, and splenic artery embolization) from January 1997 to January 2010 at Beijing Shijitan Hospital. Two hundred and nine patients (121 male and 88 female, aged 25-69 years, mean 48.3 ± 12.5 years) with complete clinical data were recruited. We evaluated the safety of the procedure (procedure-related death and serious complications), change of portal vein pressure before and after TIPS, symptom relief [e.g., ascites, hydrothorax, esophageal gastric-fundus variceal bleeding (EGVB)], cumulative rates of survival, and distributary channel restenosis. The characteristics of the patients surviving ≥ 5 and < 5 years were also analyzed. RESULTS: The portosystemic pressure was decreased from 29.0 ± 4.1 mmHg before TIPS to 18.1 ± 2.9 mmHg after TIPS (t = 69.32, P < 0.05). Portosystemic pressure was decreased and portal hypertension symptoms were ameliorated. During the 5 year follow-up, the total recurrence rate of resistant ascites or hydrothorax was 7.2% (15/209); 36.8% (77/209) for EGVB; and 39.2% (82/209) for hepatic encephalopathy. The cumulative rates of distributary channel restenosis at 1, 2, 3, 4, and 5 years were 17.2% (36/209), 29.7% (62/209), 36.8% (77/209), 45.5% (95/209) and 58.4% (122/209), respectively. No procedure-related deaths and serious complications (e.g., abdominal bleeding, hepatic failure, and distant metastasis) occurred. Moreover, Child-Pugh score, portal vein tumor thrombosis, lesion diameter, hepatic arterio-portal fistulas, HCC diagnosed before or after TIPS, stent type, hepatic encephalopathy, and type of other

  1. Transjugular intrahepatic portosystemic shunt with covered stents for hepatocellular carcinoma with portal vein tumor thrombosis

    PubMed Central

    Zhao, Jian-Bo; Feng, Chao; Zhu, Qiao-Hua; He, Xiao-Feng; Li, Yan-Hao; Chen, Yong

    2014-01-01

    AIM: To evaluate transjugular intrahepatic portosystemic shunt (TIPS) with covered stents for hepatocellular carcinoma (HCC) with main portal vein tumor thrombus (PVTT). METHODS: Eleven advanced HCC patients (all male, aged 37-78 years, mean: 54.3 ± 12.7 years) presented with acute massive upper gastrointestinal bleeding (n = 9) or refractory ascites (n = 2) due to tumor thrombus in the main portal vein. The diagnosis of PVTT was based on contrast-enhanced computed tomography and color Doppler sonography. The patients underwent TIPS with covered stents. Clinical characteristics and average survival time of 11 patients were analyzed. Portal vein pressure was assessed before and after TIPS. The follow-up period was 2-18 mo. RESULTS: TIPS with covered stents was successfully completed in all 11 patients. The mean portal vein pressure was reduced from 32.0 to 11.8 mmHg (t = 10.756, P = 0.000). Gastrointestinal bleeding was stopped in nine patients. Refractory ascites completely disappeared in one patient and was alleviated in another. Hepatic encephalopathy was observed in six patients and was resolved with drug therapy. During the follow-up, ultrasound indicated the patency of the shunt and there was no recurrence of symptoms. Death occurred 2-14 mo (mean: 5.67 mo) after TIPS in nine cases, which were all due to multiple organ failure. In the remaining two cases, the patients were still alive at the 16- and 18-mo follow-up, respectively. CONCLUSION: TIPS with covered stents for HCC patients with tumor thrombus in the main portal vein is technically feasible, and short-term efficacy is favorable. PMID:24587637

  2. Cardiac and renal effects of a transjugular intrahepatic portosystemic shunt in cirrhosis.

    PubMed

    Busk, Troels M; Bendtsen, Flemming; Møller, Søren

    2013-05-01

    Refractory ascites and recurrent variceal bleeding are among the serious complications of portal hypertension and cirrhosis for which a transjugular intrahepatic portosystemic shunt (TIPS) can be used. Cirrhotic patients have varying degrees of haemodynamic derangement, mainly characterized by peripheral arterial vasodilatation, central underfilling and activation of several vasoactive systems. These changes affect the heart, the lungs and the kidneys in particular. The cardiac effects of TIPS are immediate and are related to the redirection of blood from the splanchnic circulation into the systemic circulation, resulting in worsening of the hyperdynamic circulation with increasing cardiac output and decreasing systemic vascular resistance; further, TIPS may unmask a latent diastolic dysfunction of the heart. However, the renal effects of TIPS seem to be beneficial as renal function tends to improve in patients with the hepatorenal syndrome. The clinical and haemodynamic effects of TIPS have been studied intensively and will be reviewed in the present paper. Considerable knowledge on the effects of TIPS on the pathophysiology of cirrhosis has been gained, but studies on the central haemodynamic effects are warranted to refine the already applied treatments and develop new treatment modalities. PMID:23325273

  3. Transjugular intrahepatic portosystemic shunt for the management of acute variceal hemorrhage

    PubMed Central

    Loffroy, Romaric; Estivalet, Louis; Cherblanc, Violaine; Favelier, Sylvain; Pottecher, Pierre; Hamza, Samia; Minello, Anne; Hillon, Patrick; Thouant, Pierre; Lefevre, Pierre-Henri; Krausé, Denis; Cercueil, Jean-Pierre

    2013-01-01

    Acute variceal hemorrhage, a life-threatening condition that requires a multidisciplinary approach for effective therapy, is defined as visible bleeding from an esophageal or gastric varix at the time of endoscopy, the presence of large esophageal varices with recent stigmata of bleeding, or fresh blood visible in the stomach with no other source of bleeding identified. Transfusion of blood products, pharmacological treatments and early endoscopic therapy are often effective; however, if primary hemostasis cannot be obtained or if uncontrollable early rebleeding occurs, transjugular intrahepatic portosystemic shunt (TIPS) is recommended as rescue treatment. The TIPS represents a major advance in the treatment of complications of portal hypertension. Acute variceal hemorrhage that is poorly controlled with endoscopic therapy is generally well controlled with TIPS, which has a 90% to 100% success rate. However, TIPS is associated with a mortality of 30% to 50% in such a setting. Emergency TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy failure, before the clinical condition worsens. Furthermore, admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized effectively. This review article discusses initial management and then focuses on the specific role of TIPS as a primary therapy to control acute variceal hemorrhage, particularly as a rescue therapy following failure of endoscopic approaches. PMID:24115809

  4. Transjugular intrahepatic portosystemic shunt for acute variceal gastrointestinal bleeding: Indications, techniques and outcomes.

    PubMed

    Loffroy, R; Favelier, S; Pottecher, P; Estivalet, L; Genson, P Y; Gehin, S; Krausé, D; Cercueil, J-P

    2015-01-01

    Acute variceal bleeding is a life-threatening condition that requires a multidisciplinary approach for effective therapy. The transjugular intrahepatic portosystemic shunt (TIPS) procedure is a minimally invasive image-guided intervention used for secondary prevention of bleeding and as salvage therapy in acute bleeding. Emergency TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy fail, before the clinical condition worsens. Furthermore, admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized effectively. This procedure involves establishment of a direct pathway between the hepatic veins and the portal veins to decompress the portal venous hypertension that is the source of the patient's bleeding. The procedure is technically challenging, especially in critically ill patients, and has a mortality of 30%-50% in the emergency setting, but has an effectiveness greater than 90% in controlling bleeding from gastro-esophageal varices. This review focuses on the role of TIPS in the setting of variceal bleeding, with emphasis on current indications and techniques for TIPS creation, TIPS clinical outcomes, and the role of adjuvant embolization of varices. PMID:26094039

  5. Transjugular Intrahepatic Portosystemic Shunt Placement During Pregnancy: A Case Series of Five Patients

    SciTech Connect

    Ingraham, Christopher R. Padia, Siddharth A. Johnson, Guy E.; Easterling, Thomas R.; Liou, Iris W.; Kanal, Kalpana M.; Valji, Karim

    2015-10-15

    Background and AimsComplications of portal hypertension, such as variceal hemorrhage and ascites, are associated with significant increases in both mortality and complications during pregnancy. Transjugular intrahepatic portosystemic shunt (TIPS) is a well-established procedure for treating portal hypertension, but the safety of TIPS during pregnancy is largely unknown. In this series, we review five patients who underwent TIPS placement while pregnant and describe their clinical outcomes.MethodsFive pregnant patients with cirrhosis and portal hypertension underwent elective TIPS for complications of portal hypertension (four for secondary prevention of variceal bleeding and one for refractory ascites). Outcomes measured were recurrent bleeding episodes or need for further paracenteses during pregnancy, estimated radiation dose to the fetus and gestational age at delivery. All patients were followed after delivery to evaluate technical and clinical success of the procedure.ResultsAll five patients survived pregnancy and went on to deliver successfully. When TIPS was performed for secondary prevention of variceal bleeding (n = 4), no patients demonstrated variceal bleeding after TIPS placement. When TIPS was performed for refractory ascites (n = 1), no further paracenteses were required. All patients delivered successfully, albeit prematurely. Average radiation dose estimated to the fetus was 16.3 mGy.ConclusionsThis series suggests that TIPS can be performed in selective pregnant patients with portal hypertension, with little added risk to the mother or fetus.

  6. Living Donor Liver Transplantation Using a Liver Graft With Congenital Intrahepatic Portosystemic Shunt

    PubMed Central

    Kamei, Hideya; Imai, Hisashi; Onishi, Yasuharu; Sugimoto, Hiroyuki; Suzuki, Kojiro; Ogura, Yasuhiro

    2016-01-01

    Background Despite of recent development of imaging modalities, congenital intrahepatic portosystemic shunt (IPSS) is rarely diagnosed. Therefore, living donor liver transplantation using a liver graft with IPSS has not been previously published. Materials and Methods We report a 28-year-old male patient with end-stage liver disease secondary to Wilson disease. His 26-year-old brother was a potential living donor, who had an IPSS of 25 mm in diameter at segment 6 as shown by computed tomography. Liver function tests were normal, and blood ammonia concentration was in the upper limit of normal. Results Living donor liver transplantation was uneventfully performed. After surgery, a recipient liver function tests showed a quick recovery, and serum ammonia levels were consistently normal. Although thrombosis inside the IPSS was confirmed by computed tomography on postoperative day 21, this thrombosis disappeared at 3 months posttransplant with anticoagulants. Currently (12 months posttransplant), the patient has fully recovered, and the IPSS is still the same size. Conclusions Based on our experience, liver allografts with IPSS can be accepted as potential liver allografts.

  7. Transjugular intrahepatic portosystemic shunt creation as treatment for refractory chylous ascites and chylothorax in a patient with cirrhosis.

    PubMed

    Kinney, Thomas B; Ferrara, Stephen L; Miller, Franklin J; Roberts, Anne C; Hassanein, Tarek

    2004-01-01

    The etiology of chylothorax is usually considered to consist of four major categories: tumors, trauma, idiopathic conditions, and miscellaneous conditions. It appears that chylothorax is a rare and underreported manifestation of cirrhosis resulting from transdiaphragmatic passage of chylous ascites. This condition can be debilitating as a result of respiratory compromise from a large volume of pleural fluid, as well as metabolic derangements, malnutrition, and immunologic impairment from loss of vital lymphatic constituents. Herein the authors present a case of a 46-year-old male patient with cirrhosis and complications of high-volume chylous ascites and chylothorax who was successfully treated with creation of a transjugular intrahepatic portosystemic shunt. PMID:14709693

  8. Radiofrequency Ablation for the Treatment of Hepatocellular Carcinoma in Patients with Transjugular Intrahepatic Portosystemic Shunts

    SciTech Connect

    Park, Jonathan K.; Al-Tariq, Quazi Z.; Zaw, Taryar M. Raman, Steven S. Lu, David S.K.

    2015-10-15

    PurposeTo assess radiofrequency (RF) ablation efficacy, as well as the patency of transjugular intrahepatic portosystemic shunts (TIPSs), in patients with hepatocellular carcinoma (HCC).Materials and MethodsRetrospective database review of patients with pre-existing TIPS undergoing RF ablation of HCC was conducted over a 159-month period ending in November 2013. TIPS patency pre- and post-RF ablation was assessed by ultrasound, angiography, and/or contrast-enhanced CT or MRI. Patient demographics and immediate post-RF ablation outcomes and complications were also reviewed.Results19 patients with 21 lesions undergoing 25 RF ablation sessions were included. Child-Pugh class A, B, and C scores were seen in 1, 13, and 5 patients, respectively. Eleven patients (58 %) ultimately underwent liver transplantation. Immediate technical success was seen in all ablation sessions without residual tumor enhancement (100 %). No patients (0 %) suffered liver failure within 1 month of ablation. Pre-ablation TIPS patency was demonstrated in 22/25 sessions (88 %). Of 22 cases with patent TIPS prior to ablation, post-ablation patency was demonstrated in 22/22 (100 %) at immediate post-ablation imaging and in 21/22 (95 %) at last follow-up (1 patient was incidentally noted to have occlusion 31 months later). No immediate complications were observed.ConclusionAblation efficacy was similar to the cited literature values for patients without TIPS. Furthermore, TIPS patency was preserved in the majority of cases. Patients with both portal hypertension and HCC are not uncommonly encountered, and a pre-existing TIPS does not appear to be a definite contraindication for RF ablation.

  9. Outcomes of Locoregional Tumor Therapy for Patients with Hepatocellular Carcinoma and Transjugular Intrahepatic Portosystemic Shunts

    SciTech Connect

    Padia, Siddharth A. Chewning, Rush H. Kogut, Matthew J. Ingraham, Christopher R. Johnson, Guy E.; Bhattacharya, Renuka; Kwan, Sharon W. Monsky, Wayne L. Vaidya, Sandeep; Hippe, Daniel S.; Valji, Karim

    2015-08-15

    PurposeLocoregional therapy for hepatocellular carcinoma (HCC) can be challenging in patients with a transjugular intrahepatic portosystemic shunt (TIPS). This study compares safety and imaging response of ablation, chemoembolization, radioembolization, and supportive care in patients with both TIPS and HCC.MethodsThis retrospective study included 48 patients who had both a TIPS and a diagnosis of HCC. Twenty-nine of 48 (60 %) underwent treatment for HCC, and 19/48 (40 %) received best supportive care (i.e., symptomatic management only). While etiology of cirrhosis and indication for TIPS were similar between the two groups, treated patients had better baseline liver function (34 vs. 67 % Child-Pugh class C). Tumor characteristics were similar between the two groups. A total of 39 ablations, 17 chemoembolizations, and 10 yttrium-90 radioembolizations were performed on 29 patients.ResultsAblation procedures resulted in low rates of hepatotoxicity and clinical toxicity. Post-embolization/ablation syndrome occurred more frequently in patients undergoing chemoembolization than ablation (47 vs. 15 %). Significant hepatic dysfunction occurred more frequently in the chemoembolization group than the ablation group. Follow-up imaging response showed objective response in 100 % of ablation procedures, 67 % of radioembolization procedures, and 50 % of chemoembolization procedures (p = 0.001). When censored for OLT, patients undergoing treatment survived longer than patients receiving supportive care (2273 v. 439 days, p = 0.001).ConclusionsAblation appears to be safe and efficacious for HCC in patients with TIPS. Catheter-based approaches are associated with potential increased toxicity in this patient population. Chemoembolization appears to be associated with increased toxicity compared to radioembolization.

  10. Clinical outcomes of transjugular intrahepatic portosystemic shunt for portal hypertension: Korean multicenter real-practice data

    PubMed Central

    Kim, Hyung Ki; Kim, Yoon Jun; Chung, Woo Jin; Kim, Soon Sun; Shim, Jae Jun; Choi, Moon Seok; Kim, Do Young; Jun, Dae Won; Um, Soon Ho; Park, Sung Jae; Woo, Hyun Young; Jung, Young Kul; Baik, Soon Koo; Kim, Moon Young; Park, Soo Young; Lee, Jae Myeong

    2014-01-01

    Background/Aims This retrospective study assessed the clinical outcome of a transjugular intrahepatic portosystemic shunt (TIPS) procedure for managing portal hypertension in Koreans with liver cirrhosis. Methods Between January 2003 and July 2013, 230 patients received a TIPS in 13 university-based hospitals. Results Of the 229 (99.6%) patients who successfully underwent TIPS placement, 142 received a TIPS for variceal bleeding, 84 for refractory ascites, and 3 for other indications. The follow-up period was 24.9±30.2 months (mean±SD), 74.7% of the stents were covered, and the primary patency rate at the 1-year follow-up was 78.7%. Hemorrhage occurred in 30 (21.1%) patients during follow-up; of these, 28 (93.3%) cases of rebleeding were associated with stent dysfunction. Fifty-four (23.6%) patients developed new hepatic encephalopathy, and most of these patients were successfully managed conservatively. The cumulative survival rates at 1, 6, 12, and 24 months were 87.5%, 75.0%, 66.8%, and 57.5%, respectively. A high Model for End-Stage Liver Disease (MELD) score was significantly associated with the risk of death within the first month after receiving a TIPS (P=0.018). Old age (P<0.001), indication for a TIPS (ascites vs. bleeding, P=0.005), low serum albumin (P<0.001), and high MELD score (P=0.006) were associated with overall mortality. Conclusions A high MELD score was found to be significantly associated with early and overall mortality rate in TIPS patients. Determining the appropriate indication is warranted to improve survival in these patients. PMID:24757655

  11. Three-Dimensional Path Planning Software-Assisted Transjugular Intrahepatic Portosystemic Shunt: A Technical Modification

    SciTech Connect

    Tsauo, Jiaywei Luo, Xuefeng; Ye, Linchao; Li, Xiao

    2015-06-15

    PurposeThis study was designed to report our results with a modified technique of three-dimensional (3D) path planning software assisted transjugular intrahepatic portosystemic shunt (TIPS).Methods3D path planning software was recently developed to facilitate TIPS creation by using two carbon dioxide portograms acquired at least 20° apart to generate a 3D path for overlay needle guidance. However, one shortcoming is that puncturing along the overlay would be technically impossible if the angle of the liver access set and the angle of the 3D path are not the same. To solve this problem, a prototype 3D path planning software was fitted with a utility to calculate the angle of the 3D path. Using this, we modified the angle of the liver access set accordingly during the procedure in ten patients.ResultsFailure for technical reasons occurred in three patients (unsuccessful wedged hepatic venography in two cases, software technical failure in one case). The procedure was successful in the remaining seven patients, and only one needle pass was required to obtain portal vein access in each case. The course of puncture was comparable to the 3D path in all patients. No procedure-related complication occurred following the procedures.ConclusionsAdjusting the angle of the liver access set to match the angle of the 3D path determined by the software appears to be a favorable modification to the technique of 3D path planning software assisted TIPS.

  12. Transjugular intrahepatic porto-systemic shunt in the elderly: Palliation for complications of portal hypertension

    PubMed Central

    Syed, Mubin I; Karsan, Hetal; Ferral, Hector; Shaikh, Azim; Waheed, Uzma; Akhter, Talal; Gabbard, Alan; Morar, Kamal; Tyrrell, Robert

    2012-01-01

    AIM: To present a dedicated series of transjugular intrahepatic porto-systemic shunts (TIPS) in the elderly since data is sparse on this population group. METHODS: A retrospective review was performed of patients at least 65 years of age who underwent TIPS at our institutions between 1997 and 2010. Twenty-five patients were referred for TIPS. We deemed that 2 patients were not considered appropriate candidates due to their markedly advanced liver disease. Of the 23 patients suitable for TIPS, the indications for TIPS placement was portal hypertension complicated by refractory ascites alone (n = 9), hepatic hydrothorax alone (n = 2), refractory ascites and hydrothorax (n = 1), gastrointestinal bleeding alone (n = 8), gastrointestinal bleeding and ascites (n = 3). RESULTS: Of these 23 attempted TIPS procedure patients, 21 patients had technically successful TIPS procedures. A total of 29 out of 32 TIPS procedures including revisions were successful in 21 patients with a mean age of 72.1 years (range 65-82 years). Three of the procedures were unsuccessful attempts at TIPS and 8 procedures were successful revisions of our existing TIPS. Sixteen of 21 patients who underwent successful TIPS (excluding 5 patients lost to follow-up) were followed for a mean of 14.7 mo. Ascites and/or hydrothorax was controlled following technically successful procedures in 12 of 13 patients. Bleeding was controlled following technically successful procedures in 10 out of 11 patients. CONCLUSION: We have demonstrated that TIPS is an effective procedure to control refractory complications of portal hypertension in elderly patients. PMID:22400084

  13. Management of Transjugular Intrahepatic Portosystemic Shunt (TIPS)-associated Refractory Hepatic Encephalopathy by Shunt Reduction Using the Parallel Technique: Outcomes of a Retrospective Case Series

    SciTech Connect

    Cookson, Daniel T. Zaman, Zubayr; Gordon-Smith, James; Ireland, Hamish M.; Hayes, Peter C.

    2011-02-15

    Purpose: To investigate the reproducibility and technical and clinical success of the parallel technique of transjugular intrahepatic portosystemic shunt (TIPS) reduction in the management of refractory hepatic encephalopathy (HE). Materials and Methods: A 10-mm-diameter self-expanding stent graft and a 5-6-mm-diameter balloon-expandable stent were placed in parallel inside the existing TIPS in 8 patients via a dual unilateral transjugular approach. Changes in portosystemic pressure gradient and HE grade were used as primary end points. Results: TIPS reduction was technically successful in all patients. Mean {+-} standard deviation portosystemic pressure gradient before and after shunt reduction was 4.9 {+-} 3.6 mmHg (range, 0-12 mmHg) and 10.5 {+-} 3.9 mmHg (range, 6-18 mmHg). Duration of follow-up was 137 {+-} 117.8 days (range, 18-326 days). Clinical improvement of HE occurred in 5 patients (62.5%) with resolution of HE in 4 patients (50%). Single episodes of recurrent gastrointestinal hemorrhage occurred in 3 patients (37.5%). These were self-limiting in 2 cases and successfully managed in 1 case by correction of coagulopathy and blood transfusion. Two of these patients (25%) died, one each of renal failure and hepatorenal failure. Conclusion: The parallel technique of TIPS reduction is reproducible and has a high technical success rate. A dual unilateral transjugular approach is advantageous when performing this procedure. The parallel technique allows repeat bidirectional TIPS adjustment and may be of significant clinical benefit in the management of refractory HE.

  14. Transjugular Intrahepatic Portosystemic Shunt Occlusion Complicated with Biliary Fistula Successfully Treated with a Stent Graft: A Case Report

    PubMed Central

    Kim, Eunyoung; Lee, Sung Won; Kim, Woo Hyeon; Bae, Si Hyun; Han, Nam Ik; Oh, Jung Suk; Chun, Ho Jong; Lee, Hae Giu

    2016-01-01

    A 43-year-old man with liver cirrhosis received transjugular intrahepatic portosystemic shunt (TIPS) for the treatment of recurrent variceal bleeding and F3 esophageal varices. During routine follow up liver ultrasound examination, six months after the implantation, TIPS occlusion was suspected and TIPS revision was performed. During the revision, moderate to severe stenosis at the hepatic venous segment of the tract and a total occlusion at the parenchymal segment of TIPS tract near the portal vein with biliary-TIPS fistula were identified with a clear visualization of the common bile duct. After the successful TIPS revision with the placement of an additional stent-graft, the biliary fistula and common bile duct were no more delineated. We herein report a rare case with an obvious visualization of biliary-TIPS fistula associated with obstruction of TIPS shunt on the tractogram and recanalization with an additional stent-graft. PMID:27127576

  15. [Treatment of refractory hepatic encephalopathy associated with insertion of a transjugular intrahepatic portosystemic shunt through new endovascular techniques: a case report].

    PubMed

    Martínez Moreno, Belén; Bellot, Pablo; de España, Francisco; Palazón, José María; Such, José; Pérez-Mateo, Miguel

    2011-01-01

    Insertion of a transjugular intrahepatic portosystemic shunt (TIPS) is an increasingly used treatment in the management of the complications of portal hypertension. However, one of the complications of this technique is refractory or recurrent hepatic encephalopathy, which poses a difficult clinical problem. We report the case of a patient who underwent TIPS insertion to control bleeding due to esophageal varices. The patient subsequently developed refractory hepatic encephalopathy, requiring reduction of the caliber of the shunt. PMID:21652116

  16. Transjugular Intrahepatic Porto-Systemic Shunt Placement in a Patient with Left-Lateral Split-Liver Transplant and Mesenterico-Left Portal Vein by Pass Placement

    SciTech Connect

    Miraglia, Roberto Maruzzelli, Luigi; Luca, Angelo

    2011-12-15

    This is a report of a successful placement of a transjugular intrahepatic porto-systemic shunt in a young patient with previous left-lateral, split-liver transplant and mesenterico-left portal vein by pass placement after posttransplant extrahepatic portal vein thrombosis.

  17. Nationwide trends and predictors of inpatient mortality in 83884 transjugular intrahepatic portosystemic shunt

    PubMed Central

    Lee, Edward Wolfgang; Kuei, Andrew; Saab, Sammy; Busuttil, Ronald W; Durazo, Francisco; Han, Steven-Huy; El-Kabany, Mohamed M; McWilliams, Justin P; Kee, Stephen T

    2016-01-01

    AIM: To evaluate and validate the national trends and predictors of in-patient mortality of transjugular intrahepatic portosystemic shunt (TIPS) in 15 years. METHODS: Using the National Inpatient Sample which is a part of Health Cost and Utilization Project, we identified a discharge-weighted national estimate of 83884 TIPS procedures performed in the United States from 1998 to 2012 using international classification of diseases-9 procedural code 39.1. The demographic, hospital and co-morbility data were analyzed using a multivariant analysis. Using multi-nominal logistic regression analysis, we determined predictive factors related to increases in-hospital mortality. Comorbidity measures are in accordance to the Comorbidity Software designed by the Agency for Healthcare Research and Quality. RESULTS: Overall, 12.3% of patients died during hospitalization with downward trend in-hospital mortality with the mean length of stay of 10.8 ± 13.1 d. Notable, African American patients (OR = 1.809 vs Caucasian patients, P < 0.001), transferred patients (OR = 1.347 vs non-transferred, P < 0.001), emergency admissions (OR = 3.032 vs elective cases, P < 0.001), patients in the Northeast region (OR = 1.449 vs West, P < 0.001) had significantly higher odds of in-hospital mortality. Number of diagnoses and number of procedures showed positive correlations with in-hospital death (OR = 1.249 per one increase in number of procedures). Patients diagnosed with acute respiratory failure (OR = 8.246), acute kidney failure (OR = 4.359), hepatic encephalopathy (OR = 2.217) and esophageal variceal bleeding (OR = 2.187) were at considerably higher odds of in-hospital death compared with ascites (OR = 0.136, P < 0.001). Comorbidity measures with the highest odds of in-hospital death were fluid and electrolyte disorders (OR = 2.823), coagulopathy (OR = 2.016), and lymphoma (OR = 1.842). CONCLUSION: The overall mortality of the TIPS procedure is steadily decreasing, though the length of stay

  18. Comparative study of endoscopy vs. transjugular intrahepatic portosystemic shunt in the management of gastric variceal bleeding

    PubMed Central

    Kochhar, Gursimran Singh; Navaneethan, Udayakumar; Hartman, Jason; Mari Parungao, Jose; Lopez, Rocio; Gupta, Ranjan; Kapoor, Baljendra; Mehta, Paresh; Sanaka, Madhu

    2015-01-01

    Background and Aim: Gastric varices are associated with high mortality. There have been conflicting reports on whether endoscopic treatment with cyanoacrylate or the placement of a transjugular intrahepatic portosystemic shunt (TIPS) is more effective in the treatment of gastric varices. We compared the outcomes of patients treated with cyanoacrylate glue or TIPS for the management of acute gastric variceal bleeding. Methods: The study was designed as a retrospective cohort analysis of patients undergoing either TIPS or endoscopic treatment with cyanoacrylate for acute gastric variceal bleeding at our institution from 2001 to 2011. Primary compared to studied between the two treatment modalities were the short-term treatment outcomes, including re-bleeding within 30 days, length of hospital stay and in-hospital mortality. Kaplan-Meier survival analysis was performed to assess factors associated with in-hospital mortality. Results: A total of 169 patients were included in the analysis. The TIPS arm contained 140 patients and the cyanoacrylate arm contained 29 patients. There was no evidence to suggest any significant differences in demographics or disease severity. There were no differences between the TIPS arm and the cyanoacrylate armtwo groups in treatment outcomes including re-bleeding within 30 days (17.4% vs. 17.2%; P = 0.98), median length of stay in the hospital (4.5 days vs. 6.0 days; P = 0.35) or in-hospital mortality (9.0% vs. 11.1%; P = 0.74). In-hospital mortality was evaluated for 149 patients and lower albumin (P = 0.015), higher MELD score (P < 0.001), higher CTP score (P = 0.005) and bleeding (P = 0.008) were all significantly associated with in-hospital death. Conclusion: These findings suggest that both treatments are equally effective. Cyanoacrylate offers a safe, effective alternative to TIPS for gastric varices, and physician may choose the best therapy for each patient, factoring in the availability of TIPS or cyanoacrylate, the individual

  19. Effect of technical parameters on transjugular intrahepatic portosystemic shunts utilizing stent grafts

    PubMed Central

    Andring, Brice; Kalva, Sanjeeva P; Sutphin, Patrick; Srinivasa, Rajiv; Anene, Alvin; Burrell, Marc; Xi, Yin; Pillai, Anil K

    2015-01-01

    AIM: To assess the effect of technical parameters on outcomes of transjugular intrahepatic portosystemic shunt (TIPS) created using a stent graft. METHODS: The medical records of 68 patients who underwent TIPS placement with a stent graft from 2008 to 2014 were reviewed by two radiologists blinded to the patient outcomes. Digital Subtraction Angiographic images with a measuring catheter in two orthogonal planes was used to determine the TIPS stent-to-inferior vena cava distance (SIVCD), hepatic vein to parenchymal tract angle (HVTA), portal vein to parenchymal tract angle (PVTA), and the accessed portal vein. The length and diameter of the TIPS stent and the use of concurrent variceal embolization were recorded by review of the patient’s procedure note. Data on re-intervention within 30 d of TIPS placement, recurrence of symptoms, and survival were collected through the patient’s chart. Cox proportional regression analysis was performed to assess the effect of these technical parameters on primary patency of TIPS, time to recurrence of symptoms, and all-cause mortality. RESULTS: There was no significant association between the SIVCD and primary patency (P = 0.23), time to recurrence of symptoms (P = 0.83), or all-cause mortality (P = 0.18). The 3, 6, and 12-mo primary patency rates for a SIVCD ≥ 1.5 cm were 82.4%, 64.7%, and 50.3% compared to 89.3%, 83.8%, and 60.6% for a SIVCD of < 1.5 cm (P = 0.29). The median time to stenosis for a SIVCD of ≥ 1.5 cm was 19.1 mo vs 15.1 mo for a SIVCD of < 1.5 cm (P = 0.48). There was no significant association between the following factors and primary patency: HVTA (P = 0.99), PVTA (P = 0.65), accessed portal vein (P = 0.35), TIPS stent diameter (P = 0.93), TIPS stent length (P = 0.48), concurrent variceal embolization (P = 0.13) and reinterventions within 30 d (P = 0.24). Furthermore, there was no correlation between these technical parameters and time to recurrence of symptoms or all-cause mortality. Recurrence of

  20. Pull-Through Technique for Recanalization of Occluded Portosystemic Shunts (TIPS): Technical Note and Review of the Literature

    SciTech Connect

    Tanaka, Toshihiro Guenther, Rolf W. Isfort, Peter; Kichikawa, Kimihiko; Mahnken, Andreas H.

    2011-04-15

    Transjugular intrahepatic portosystemic shunt (TIPS) dysfunction is an important problem after creation of shunts. Most commonly, TIPS recanalization is performed via the jugular vein approach. Occasionally it is difficult to cross the occlusion. We describe a hybrid technique for TIPS revision via a direct transhepatic access combined with a transjugular approach. In two cases, bare metal stents or polytetrafluoroethylene (PTFE)-covered stent grafts had been placed in TIPS tract previously, and they were completely obstructed. The tracts were inaccessible via the jugular vein route alone. In each case, after fluoroscopy or computed tomography-guided transhepatic puncture of the stented segment of the TIPS, a wire was threaded through the shunt and snared into the right jugular vein. The TIPS was revised by balloon angioplasty and additional in-stent placement of PTFE-covered stent grafts. The patients were discharged without any complications. Doppler sonography 6 weeks after TIPS revision confirmed patency in the TIPS tract and the disappearance of ascites. We conclude that this technique is feasible and useful, even in patients with previous PTFE-covered stent graft placement.

  1. Endovascular Management of Refractory Hepatic Encephalopathy Complication of Transjugular Intrahepatic Portosystemic Shunt (TIPS): Comprehensive Review and Clinical Practice Algorithm.

    PubMed

    Pereira, Keith; Carrion, Andres F; Salsamendi, Jason; Doshi, Mehul; Baker, Reginald; Kably, Issam

    2016-02-01

    Transjugular intrahepatic portosystemic shunt (TIPS) has evolved as an effective intervention for treatment of complications of portal hypertension. The use of polytetrafluoroethylene-covered stents have improved the patency of the shunts and diminished the incidence of TIPS dysfunction. However, TIPS-related refractory hepatic encephalopathy (rHE) poses a significant challenge. Approximately 3-7 % of patients with TIPS develop rHE. Refractory hepatic encephalopathy is defined as a recurrent or persistent encephalopathy despite appropriate medical treatment. Hepatic encephalopathy can be an extremely debilitating complication that profoundly affects quality of life. The approach to management of patients with rHE is complex and typically requires collaboration between different specialties. Liver transplantation is the ultimate treatment for rHE; however, the ongoing shortage of organ donation markedly limits this treatment option. Alternative therapies such as shunt occlusion or reduction can control symptoms and serve as a 'bridge' therapy to liver transplantation. Therefore, interventional radiologists play a key role in the management of these patients by offering a variety of endovascular techniques. The purpose of this review is to highlight some of these endovascular techniques and to develop a therapeutic algorithm that can be applied in clinical practice for the management of rHE. PMID:26285910

  2. Primary Implantation of Polyester-Covered Stent-Grafts for Transjugular Intrahepatic Portosystemic Stent Shunts (TIPSS): A Pilot Study

    SciTech Connect

    Cejna, Manfred; Thurnher, Siegfried; Pidlich, Johann; Kaserer, Klaus; Schoder, Maria; Lammer, Johannes

    1999-07-15

    Purpose: To investigate whether placement of a polyester-covered stent-graft increases the primary patency of transjugular intrahepatic portosystemic stent shunts (TIPSS). Methods: Between 1995 and 1997 Cragg Endopro or Passager MIBS stent-grafts were used for the creation of TIPSS in eight male patients, 35-59 years of age (mean 48 years). All patients suffered from recurrent variceal bleeding and/or refractory ascites due to liver cirrhosis. Seven stent-grafts were dilated to a diameter of 10 mm, one to 12 mm. Follow-up was performed with duplex ultrasound, clinical assessment, and angiography. Results: The technical success rate for creation of a TIPSS was 100%. The mean portosystemic pressure gradient decreased from 25 mmHg to 12 mmHg. In seven of eight patients TIPSS dysfunction occurred between 2 days and 3 years after stent-graft placement. In one patient the TIPSS is still primarily patent (224 days after creation). The secondary patency rates are 31 days to 3 years. Conclusion: The primary use of polyester-covered stent-grafts for TIPSS did not increase primary patency rates in our small series.

  3. Transsplenic portal vein reconstruction-transjugular intrahepatic portosystemic shunt in a patient with portal and splenic vein thrombosis.

    PubMed

    Salsamendi, Jason T; Gortes, Francisco J; Shnayder, Michelle; Doshi, Mehul H; Fan, Ji; Narayanan, Govindarajan

    2016-09-01

    Portal vein thrombosis (PVT) is a potential complication of cirrhosis and can worsen outcomes after liver transplant (LT). Portal vein reconstruction-transjugular intrahepatic portosystemic shunt (PVR-TIPS) can restore flow through the portal vein (PV) and facilitate LT by avoiding complex vascular conduits. We present a case of transsplenic PVR-TIPS in the setting of complete PVT and splenic vein (SV) thrombosis. The patient had a 3-year history of PVT complicated by abdominal pain, ascites, and paraesophageal varices. A SV tributary provided access to the main SV and was punctured percutaneously under ultrasound scan guidance. PV access, PV and SV venoplasty, and TIPS placement were successfully performed without complex techniques. The patient underwent LT with successful end-to-end anastomosis of the PVs. Our case suggests transsplenic PVR-TIPS to be a safe and effective alternative to conventional PVR-TIPS in patients with PVT and SV thrombosis. PMID:27594947

  4. Transjugular Intrahepatic Portosystemic Shunt for Treatment of Cirrhosis-related Chylothorax and Chylous Ascites: Single-institution Retrospective Experience

    SciTech Connect

    Kikolski, Steven G. Aryafar, Hamed Rose, Steven C.; Roberts, Anne C.; Kinney, Thomas B.

    2013-08-01

    PurposeTo investigate the efficacy and safety of the use of transjugular intrahepatic portosystemic shunt (TIPS) creation to treat cirrhosis-related chylous collections (chylothorax and chylous ascites).MethodsWe retrospectively reviewed data from four patients treated for refractory cirrhosis-related chylous collections with TIPS at our institution over an 8 year period.ResultsOne patient had chylothorax, and three patients had concomitant chylothorax and chylous ascites. There were no major complications, and the only procedure-related complications occurred in two patients who had mild, treatable hepatic encephalopathy. All patients had improvement as defined by decreased need for thoracentesis or paracentesis, with postprocedure follow-up ranging from 19 to 491 days.ConclusionTIPS is a safe procedure that is effective in the treatment of cirrhosis-related chylous collections.

  5. Spontaneous thrombosis of congenital extrahepatic portosystemic shunt (Abernethy malformation) simulating inguinal hernia incarceration.

    PubMed

    Afzal, Samara; Nair, Amit; Grainger, Jennie; Latif, Sherif; Rehman, Atiq-ur

    2010-08-01

    Tender lumps in the inguinal region are often explored emergently to treat suspected hernial strangulation. We discuss the case of an adult male who presented acutely with a tender inguinal swelling and raised inflammatory markers and was therefore deemed as requiring surgical exploration. However preoperative abdominal computerized tomography (CT) revealed an extensive thrombosing congenital venous malformation of portosystemic origin with extension into the symptomatic inguinal canal. A potentially lethal exsanguination from surgery was thus avoided. PMID:20551093

  6. Long-Term Follow-Up After Successful Transjugular Intrahepatic Portosystemic Shunt Placement in a Pediatric Patient with Budd-Chiari Syndrome

    SciTech Connect

    Carnevale, Francisco Cesar Szejnfeld, Denis Moreira, Airton Mota; Gibelli, Nelson; Gregorio, Miguel Angel De; Tannuri, Uenis; Cerri, Giovanni Guido

    2008-11-15

    Orthotopic liver transplantation is the standard of care in patients with Budd-Chiari syndrome (BCS), and transjugular intrahepatic portosystemic shunt (TIPS) has become an important adjunct procedure while the patient is waiting for a liver. No long-term follow up of TIPS in BCS patients has been published in children. We report successful 10-year follow-up of a child with BCS and iatrogenic TIPS dysfunction caused by oral contraceptive use.

  7. Transjugular Intrahepatic Portosystemic Shunt Creation in Budd-Chiari Syndrome: Percutaneous Ultrasound-Guided Direct Simultaneous Puncture of the Portal Vein and Vena Cava

    SciTech Connect

    Boyvat, Fatih Aytekin, Cueneyt; Harman, Ali; Ozin, Yasemin

    2006-10-15

    Budd-Chiari syndrome (BCS) is an uncommon disorder that can be life-threatening, depending on the degree of hepatic venous outflow obstruction. Transjugular intrahepatic portosystemic shunt (TIPS) provides decompression of the congested liver but the hepatic vein obstruction makes the procedure more difficult. We describe a modified method that involved a single percutaneous puncture of the portal vein and inferior vena cava simultaneously for TIPS creation in a patient with BCS.

  8. Transjugular Intrahepatic Portosystemic Shunt, Mechanical Aspiration Thrombectomy, and Direct Thrombolysis in the Treatment of Acute Portal and Superior Mesenteric Vein Thrombosis

    SciTech Connect

    Ferro, Carlo; Rossi, Umberto G. Bovio, Giulio; Dahamane, M'Hamed; Centanaro, Monica

    2007-09-15

    A patient was admitted because of severe abdominal pain, anorexia, and intestinal bleeding. Contrast-enhanced multidetector computed tomography demonstrated acute portal and superior mesenteric vein thrombosis (PSMVT). The patient was treated percutaneously with transjugular intrahepatic portosystemic shunt (TIPS), mechanical aspiration thrombectomy, and direct thrombolysis, and 1 week after the procedure, complete patency of the portal and superior mesenteric veins was demonstrated. TIPS, mechanical aspiration thrombectomy, and direct thrombolysis together are promising endovascular techniques for the treatment of symptomatic acute PSMVT.

  9. A 25-year experience with total portosystemic shunts and reappraisal of colon exclusion.

    PubMed

    Talman, E A; Johns, T N; Regan, W W

    1983-05-01

    The results of 43 total shunt procedures for bleeding esophageal varices performed consecutively at two community hospitals from 1956 to 1981 are reviewed. Of 15 patients with immediate preoperative bilirubins greater than 2.0 mg/dl, 11 died following shunt surgery. Of 28 other shunted patients with immediate preoperative bilirubins of less than 2.0 mg/dl, there was only one in-hospital death, thus substantiating the contention that the last preoperative serum bilirubin value is the best predictor of operative mortality. Of ten patients with appreciable ascites verified at the time of operation, there were only two survivors, and both of these had preoperative bilirubins of less than 2.0 mg/dl. Twenty-nine of the 31 patients who left the hospital were still living at least one year after operation. All 23 patients operated on prior to 1977 were available for 5-year follow-up, and there were 14 survivors (60%). Thirteen of the 31 patients (42%) manifested some degree of hepatic encephalopathy, as interpreted by necessity for protein restriction and either Neomycin or Lactulose. Incapacitating post-shunt hepatic encephalopathy developed in one patient who required recurrent hospitalizations for episodic coma. This patient underwent a total abdominal colectomy and ileorectal anastomosis, with elimination of all episodes of encephalopathy for the subsequent 4 1/2 years. The previous 16 cases in the literature of surgical treatment of post-shunt encephalopathy are reviewed, and the efficacy of such colon exclusion is reassessed. PMID:6601935

  10. Technical concepts for vascular electromagnetic navigated interventions: aortic in situ fenestration and transjugular intrahepatic porto-systemic shunts.

    PubMed

    Penzkofer, Tobias; Isfort, Peter; Na, Hong-Sik; Wilkmann, Christoph; Osterhues, Sabine; Besting, Andreas; Hänisch, Christoph; Bisplinghoff, Stefan; Jansing, Johannes; von Werder, Sylvie; Gooding, Jorge; de la Fuente, Mathias; Mahnken, Andreas H; Disselhorst-Klug, Catherine; Schmitz-Rode, Thomas; Kuhl, Christiane K; Bruners, Philipp

    2014-04-01

    This work presents concepts for complex endovascular procedures using electromagnetic navigation technology (EMT). Navigation software interfacing a standard commercially available navigation system was developed, featuring registration, electromagnetic field distortion correction, breathing motion detection and gating, and state-of-the-art 3D imaging post processing. Protocols for endovascularly placed, in-situ fenestrated abdominal aortic stent grafts and an EMT guided transjugular intrahepatic portosystemic shunt (TIPSS) creation have been designed. A dedicated set of interventional devices was developed for each of the procedures: For aortic in-situ fenestration a combination of high-porosity stentgrafts, steerable catheters and electromagnetically navigated guidewires was used, for TIPSS a dual-navigated (sheath and stylet) TIPSS-device was designed and manufactured. The developed devices underwent phantom testing, in preparation for animal experiments to prove the feasibility of the approach. Once established, these systems could aid in performing these challenging interventional radiology procedures, exploiting the unique characteristics of electromagnetic navigation and solving multiple of the problems associated with these interventions being performed under X-ray fluoroscopy, such as lacking real-time 3D information or extensive exposure to ionizing radiation. PMID:24176959

  11. Acute Effects of Liver Vein Occlusion by Stent-Graft Placed in Transjugular Intrahepatic Portosystemic Shunt Channel: An Experimental Study

    SciTech Connect

    Keussen, Inger Bergqvist, Lennart; Rissler, Pehr; Cwikiel, Wojciech

    2006-02-15

    The purpose of this study was to evaluate the effects of hepatic vein occlusion by stent-graft used in transjugular intrahepatic portosystemic shunt (TIPS). The experiments were performed in six healthy pigs under general anesthesia. Following percutaneous transhepatic implantation of a port-a-cath in the right hepatic vein, TIPS was created with a stent-graft (Viatorr; W L Gore, Flagstaff, AZ, USA). The outflow from the hepatic vein, blocked by the stent-graft was documented by injection of contrast medium and repeated injections of {sup 99}Tc{sup m}-labeled human serum albumin through the port-a-cath. After 2 weeks, the outflow was re-evaluated, the pigs were sacrificed, and histopathologic examination of the liver was performed. Occlusion of the hepatic vein by a stent-graft had a short and temporary effect on the outflow. Histopathological examination from the affected liver segment showed no divergent pattern. Stent-grafts used in TIPS block the outflow from the liver vein, but do not have a prolonged circulatory effect and do not affect the liver parenchyma.

  12. Multiple acquired extrahepatic portosystemic shunts secondary to veno-occlusive disease in a young German shepherd

    PubMed Central

    Fredholm, Dan

    2009-01-01

    An 11-month-old German shepherd presented with behavioral abnormalities. Histopathologic analysis of liver biopsies taken during exploratory laparotomy revealed veno-occlusive disease caused by fibrosis of the hepatic central veins leading to secondary portal hypertension, development of shunting vessels, and hepatic encephalopathy. The fibrosis was likely congenital in origin. PMID:19794875

  13. Hyperammonemia and Systemic Inflammatory Response Syndrome Predicts Presence of Hepatic Encephalopathy in Dogs with Congenital Portosystemic Shunts

    PubMed Central

    Tivers, Mickey S.; Handel, Ian; Gow, Adam G.; Lipscomb, Vicky J.; Jalan, Rajiv; Mellanby, Richard J.

    2014-01-01

    Hepatic encephalopathy (HE) is an important cause of morbidity and mortality in patients with liver disease. The pathogenesis of he is incompletely understood although ammonia and inflammatory cytokines have been implicated as key mediators. To facilitate further mechanistic understanding of the pathogenesis of HE, a large number of animal models have been developed which often involve the surgical creation of an anastomosis between the hepatic portal vein and the caudal vena cava. One of the most common congenital abnormalities in dogs is a congenital portosystemic shunt (cpss), which closely mimics these surgical experimental models of HE. Dogs with a cPSS often have clinical signs which mimic clinical signs observed in humans with HE. Our hypothesis is that the pathogenesis of HE in dogs with a cPSS is similar to humans with HE. The aim of the study was to measure a range of clinical, haematological and biochemical parameters, which have been linked to the development of HE in humans, in dogs with a cPSS and a known HE grade. One hundred and twenty dogs with a cPSS were included in the study and multiple regression analysis of clinical, haematological and biochemical variables revealed that plasma ammonia concentrations and systemic inflammatory response syndrome scores predicted the presence of HE. Our findings further support the notion that the pathogenesis of canine and human HE share many similarities and indicate that dogs with cPSS may be an informative spontaneous model of human HE. Further investigations on dogs with cPSS may allow studies on HE to be undertaken without creating surgical models of HE thereby allowing the number of large animals used in animal experimentation to be reduced. PMID:24392080

  14. Use of technetium-99m sulfur colloid to evaluate changes in reticuloendothelial function in dogs with experimentally induced chronic biliary cirrhosis and portosystemic shunting.

    PubMed

    Koblik, P D; Hornof, W J; Yen, C K; Fisher, P E; Komtebedde, J

    1995-05-01

    Technetium-99m sulfur colloid scintigraphy was used to study alterations of reticuloendothelial function in 7 dogs with experimentally induced biliary cirrhosis and portosystemic shunting. Scintigraphic studies were performed before and 6 weeks after common bile duct ligation. Radiocolloid plasma clearance rate was determined by measuring activity in plasma samples and by analyzing the rate of liver uptake on dynamic scintigraphic image sequences. Percentage of uptake in the liver, spleen, and lungs, as well as the ratio of hepatic-to-extrahepatic uptake, was determined from static equilibrium images. Relative to preoperative values, there were significant decreases in plasma clearance rate, percentage of liver uptake, and ratio of hepatic-to-extrahepatic uptake and significant increases in percentage of spleen and lung uptake on postoperative studies. The mechanism of technetium-99m-labeled sulfur colloid extraction by the liver is different from that of other radiocolloids; it does not require active phagocytosis or pinocytosis. Thus, liver uptake of this tracer principally reflects effective liver blood flow. Portosystemic shunting was documented in these dogs at the time of the postoperative radiocolloid scans, and we believed was responsible for the decrease in liver reticuloendothelial activity. Possible mechanisms for the increased splenic and pulmonary reticuloendothelial activities are discussed. PMID:7661466

  15. Evaluation of surgical outcome, complications, and mortality in dogs undergoing preoperative computed tomography angiography for diagnosis of an extrahepatic portosystemic shunt: 124 cases (2005–2014)

    PubMed Central

    Brunson, Benjamin W.; Case, J. Brad; Ellison, Gary W.; Fox-Alvarez, W. Alexander; Kim, Stanley E.; Winter, Matthew; Garcia-Pereira, Fernando L.; Farina, Lisa L.

    2016-01-01

    This study evaluated the safety of preoperative computed tomography angiography (CTA) and its effect on surgical time and clinical outcomes in dogs that underwent surgical correction of a single congenital extrahepatic portosystemic shunt (CEPSS). Patient data were retrospectively collected from medical records and owner communications for 124 dogs with single CEPSS, undergoing preoperative CTA (n = 43) or not (n = 81) which were surgically treated from 2005 to 2014. The frequency of major postoperative complications was 4.7% and 9.9% for the CTA and no CTA groups, respectively (P = 0.49). Mean ± standard deviation (SD) surgical time for the preoperative CTA group was 84 ± 40 min and 81 ± 31 min for the no CTA group (P = 0.28). We conclude that anesthetized preoperative CTA appears to be a safe method for diagnosis and surgical planning in dogs with single CEPSS, and does not appear to affect surgical procedure time, complication rate, or clinical outcome. PMID:26740699

  16. Multidetector-Row Computed Tomography in the Evaluation of Transjugular Intrahepatic Portosystemic Shunt Performed with Expanded-Polytetrafluoroethylene-Covered Stent-Graft

    SciTech Connect

    Fanelli, Fabrizio Bezzi, Mario; Bruni, Antonio; Corona, Mario; Boatta, Emanuele; Lucatelli, Pierleone; Passariello, Roberto

    2011-02-15

    We assessed, in a prospective study, the efficacy of multidetector spiral computed tomography (MDCT) in the evaluation of transjugular intrahepatic portosystemic shunt (TIPS) patency in patients treated with the Viatorr (Gore, Flagstaff, AZ) expanded-polytetrafluoroethylene (e-PTFE)-covered stent-graft. Eighty patients who underwent TIPS procedure using the Viatorr self-expanding e-PTFE stent-graft were evaluated at follow-up of 1, 3, 6, and 12 months with clinical and laboratory tests as well as ultrasound-color Doppler (USCD) imaging. In case of varices, upper gastrointestinal endoscopy was also performed. In addition, the shunt was evaluated using MDCT at 6 and 12 months. In all cases of abnormal findings and discrepancy between MDCT and USCD, invasive control venography was performed. MDCT images were acquired before and after injection of intravenous contrast media on the axial plane and after three-dimensional reconstruction using different algorithms. MDCT was successfully performed in all patients. No artefacts correlated to the Viatorr stent-graft were observed. A missing correlation between UCSD and MDCT was noticed in 20 of 80 (25%) patients. Invasive control venography confirmed shunt patency in 16 (80%) cases and shunt malfunction in 4 (20%) cases. According to these data, MDCT sensitivity was 95.2%; specificity was 96.6%; and positive (PPV) and negative predictive values (NPV) were 90.9 and 98.2%, respectively. USCD sensitivity was 90%; specificity was 75%; and PPV and NPV were 54.5 and 95.7%, respectively. A high correlation (K value = 0.85) between MDCT and invasive control venography was observed. On the basis of these results, MDCT shows superior sensitivity and specificity compared with USCD in those patients in whom TIPS was performed with the Viatorr stent-graft. MDCT can be considered a valid tool in the follow-up of these patients.

  17. Use of the Viatorr Expanded Polytetrafluoroethylene-Covered Stent-Graft for Transjugular Intrahepatic Portosystemic Shunt Creation in Children: Initial Clinical Experience

    SciTech Connect

    Mermuys, Koen; Maleux, Geert Heye, Sam; Lombaerts, Rita; Nevens, Frederik

    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 until 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.

  18. Transjugular intrahepatic portosystemic shunting (TIPS) with balloon-expandable and self-expanding stents: Technical and clinical aspects after 3 1/2 years' experience

    SciTech Connect

    Tesdal, I. Kaare; Jaschke, Werner; Buehler, Mathias; Adamus, Ralf; Filser, Thomas; Holm, Eggert; Georgi, Max

    1997-01-15

    Purpose. To evaluate prospectively our experience with transjugular intrahepatic portosystemic shunt (TIPS) using four different metallic stents. Methods. Between November 1991 and April 1995, 57 patients (41 men and 16 women; age 35-72 years, mean 54 years) underwent the TIPS procedure. Techniques for portal vein localization before and during TIPS were fluoroscopy, computed tomography (CT) studies, wedged hepatic venography, arterial portography, and ultrasound. After predilation we deployed balloon-expandable (n=48) and self-expanding (n=45) metallic stents. Fifteen patients underwent variceal embolization. Initial follow-up angiograms (mean 6.9 months, range 3-24 months) were obtained in 39 of these patients. Results. Fifty-three patients (93%) had successful TIPS placement. The mean decrease in portal pressure was 42.7%. Besides fluoroscopy, the most helpful techniques for portal vein localization were venography and CT. Residual stenosis (n=1) and late shortening (n=4) of Wallstents resulted in shunt dysfunction. The technical problems encountered with the Palmaz stent resulted from its lack of flexibility. We combined balloon-expandable and self-expanding stents in 12 patients. The 30-day and late follow-up (mean 11.9 months) percutaneous reintervention rates were 11.3% and 64.2%, respectively. There were no clinically significant complications related to the TIPS insertions. Conclusion. An ideal stent does not exist for TIPS, and the authors recommend combining a Palmaz stent with a flexible self-expanding stent.

  19. Aberrant Expression and Distribution of Enzymes of the Urea Cycle and Other Ammonia Metabolizing Pathways in Dogs with Congenital Portosystemic Shunts

    PubMed Central

    van Straten, Giora; van Steenbeek, Frank G.; Grinwis, Guy C. M.; Favier, Robert P.; Kummeling, Anne; van Gils, Ingrid H.; Fieten, Hille; Groot Koerkamp, Marian J. A.; Holstege, Frank C. P.; Rothuizen, Jan; Spee, Bart

    2014-01-01

    The detoxification of ammonia occurs mainly through conversion of ammonia to urea in the liver via the urea cycle and glutamine synthesis. Congenital portosystemic shunts (CPSS) in dogs cause hyperammonemia eventually leading to hepatic encephalopathy. In this study, the gene expression of urea cycle enzymes (carbamoylphosphate synthetase (CPS1), ornithine carbamoyltransferase (OTC), argininosuccinate synthetase (ASS1), argininosuccinate lyase (ASL), and arginase (ARG1)), N-acetylglutamate synthase (NAGS), Glutamate dehydrogenase (GLUD1), and glutamate-ammonia ligase (GLUL) was evaluated in dogs with CPSS before and after surgical closure of the shunt. Additionally, immunohistochemistry was performed on urea cycle enzymes and GLUL on liver samples of healthy dogs and dogs with CPSS to investigate a possible zonal distribution of these enzymes within the liver lobule and to investigate possible differences in distribution in dogs with CPSS compared to healthy dogs. Furthermore, the effect of increasing ammonia concentrations on the expression of the urea cycle enzymes was investigated in primary hepatocytes in vitro. Gene-expression of CPS1, OTC, ASL, GLUD1 and NAGS was down regulated in dogs with CPSS and did not normalize after surgical closure of the shunt. In all dogs GLUL distribution was localized pericentrally. CPS1, OTC and ASS1 were localized periportally in healthy dogs, whereas in CPSS dogs, these enzymes lacked a clear zonal distribution. In primary hepatocytes higher ammonia concentrations induced mRNA levels of CPS1. We hypothesize that the reduction in expression of urea cycle enzymes, NAGS and GLUD1 as well as the alterations in zonal distribution in dogs with CPSS may be caused by a developmental arrest of these enzymes during the embryonic or early postnatal phase. PMID:24945279

  20. MELD Score as a Predictor of Early Death in Patients Undergoing Elective Transjugular Intrahepatic Portosystemic Shunt (TIPS) Procedures

    SciTech Connect

    Montgomery, Aaron; Ferral, Hector Vasan, Rajiv; Postoak, Darren W.

    2005-04-15

    Purpose. To Evaluate the MELD score as a predictor of 30-day mortality in patients undergoing elective TIPS procedures. Methods. This was a retrospective, IRB-approved study. The medical records of all patients who underwent a TIPS procedure between May 1, 1999 and June 1, 2003 in a single institution were reviewed. Patients who underwent elective TIPS were selected. Elective TIPS was performed in 119 patients with a mean age of 55.1 ({+-} 9.6) years. The MELD and Child-Pugh scores before TIPS, etiology of cirrhosis, portosystemic gradients before and after TIPS, procedure time, and procedural complications were obtained from the medical records. The MELD and Child-Pugh scores before TIPS were compared between the survivor group (SG) and the early death (EDG) group. The early death rate was calculated for MELD score subgroups (1-10, 11-17, 18-24, and >24). Data were analyzed using the Fisher exact test, chi-square test and independent-sample t-test. A p value of less than 0.05 was considered significant. Results. Technical success rate was 100%. The early death rate was 10.9% (13/119). The mean MELD scores before TIPS were 19.4 ({+-} 5.9) (EDG) and 14 ({+-} 4.2) (SG) (p = 0.025). The early death rate was highest in the pre-TIPS MELD > 24 subgroup. The Child-Pugh scores were 9.0 ({+-} 1.6) (SG) and 9.8 {+-} 1.06 (EDG) (p 0.08). The mean portosystemic gradients before TIPS were 20.5 ({+-} 7.7) mmHg (EDG) and 22.7 ({+-} 7.3) (SG) (p > 1) and the mean portosystemic gradients after TIPS were 6.5 ({+-} 3.5) (EDG) and 6.9 ({+-} 2.4) (SG) (p > 1). The mean procedural times were 95.6 ({+-} 8.4) min (EDG) and 89.2 ({+-} 7.5) min (SG) (p > 1). No early death was attributed to a fatal complication during TIPS. Conclusion. The MELD score is useful in identifying patients at a higher risk of early death after an elective TIPS. On the basis of our results, we do not endorse elective TIPS in patients with MELD scores > 24.

  1. Combining Transjugular Intrahepatic Portosystemic Shunt with Balloon-Occluded Retrograde Transvenous Obliteration or Augmenting TIPS with Variceal Embolization for the Management of Gastric Varices: An Evolving Middle Ground?

    PubMed Central

    Saad, Wael E.

    2014-01-01

    The American College of Radiology Appropriateness Criteria Committee on interventional radiology has recently recognized balloon-occluded retrograde transvenous obliteration (BRTO) as a viable alternative to transjugular intrahepatic portosystemic shunt (TIPS) in certain anatomic and clinical scenarios for the management of gastric varices. However, it did not define these particular scenarios where BRTO would be a viable alternative. With the increased practice of BRTO in the United States, a debate ensues in the United States and Europe whether BRTO or TIPS should be the primary endovascular procedure of choice for gastric varices. From a conservative standpoint, BRTO is reserved for patients who are not TIPS candidates, while other institutions leave the decision to operator preference and “favorable anatomy” for either procedure. To add to the debate, there is a heightened interest in the improved efficacy of variceal embolization (metallic/bland embolization) concurrent with TIPS compared with TIPS without embolization, and a recent article describing a combination of TIPS and BRTO that demonstrated impressive results superior to BRTO or TIPS alone. This article discusses the most recent outcomes of TIPS and embolization of gastric varices as well as combining BRTO and TIPS. PMID:25177089

  2. Systemic and Splanchnic Lipopolysaccharide and Endothelin-1 Plasma Levels in Liver Cirrhosis before and after Transjugular Intrahepatic Portosystemic Shunt

    PubMed Central

    Meng, Jiaxiang; Wang, Qing; Liu, Kai; Yang, Shuofei; Fan, Xinxin; Liu, Baochen; He, Changsheng; Wu, Xingjiang

    2016-01-01

    Lipopolysaccharide (LPS) and endothelin- (ET-) 1 may aggravate portal hypertension by increasing intrahepatic resistance and splanchnic blood flow. In the portal vein, after TIPS shunting, LPS and ET-1 were significantly decreased. Our study suggests that TIPS can benefit cirrhotic patients not only in high hemodynamics related variceal bleeding but also in intestinal bacterial translocation associated complications such as endotoxemia. PMID:26941788

  3. MELD-Na as a prognostic indicator of 30- and 90-day mortality in patients with end-stage liver disease after creation of transjugular intrahepatic portosystemic shunt.

    PubMed

    Ahmed, Rezwan; Santhanam, Prasanna; Rayyan, Yaser

    2015-10-01

    Previous studies have shown that the Model for End-Stage Liver Disease (MELD) score is superior to other liver disease scoring systems to establish optimal candidates for transjugular intrahepatic portosystemic shunt (TIPS) procedure and liver transplantation. Our aim was to compare MELD-Na score with MELD score as a predictor of 30-day as well as 90-day mortality for individuals with end-stage liver disease (ESLD) after creation of TIPS. We performed a chart review on cirrhotic patients who underwent TIPS procedure and documented presence and severity of ascites and hepatic encephalopathy, patient laboratory values, and results from TIPS procedures. We compared continuous variables by Student's t-test for independent samples and categorical variables by χ-test(s). In non-normal distributions, a nonparametric test was used. We performed a logistic regression to determine the effects of several variables and analyzed variable predictors of likelihood of death within 30 and 90 days of TIPS procedure. Of the six predictor variables, only MELD-Na score was a statistically significant predictor of 30- and 90-day mortality following TIPS procedure for ESLD (P=0.028). For each one point increase in MELD-Na score, the odds of death increased by 1.15 times [95% confidence interval (1.02-1.30), P=0.28]. Since hyponatremia may be associated with poor prognostic features of overall health, its incorporation into the MELD scoring system to predict mortality in ESLD after creation of TIPS serves a useful purpose. Our single-center experience suggests that the MELD-Na score is the most effective predictor of survival after TIPS creation. PMID:26111072

  4. Efficacy of TACE in TIPS Patients: Comparison of Treatment Response to Chemoembolization for Hepatocellular Carcinoma in Patients With and Without a Transjugular Intrahepatic Portosystemic Shunt

    SciTech Connect

    Kuo, Yuo-Chen Kohi, Maureen P. Naeger, David M. Tong, Ricky T. Kolli, K. Pallav Taylor, Andrew G. Laberge, Jeanne M. Kerlan, Robert K. Fidelman, Nicholas

    2013-10-15

    Purpose: To compare treatment response after transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) in patients with and without a transjugular intrahepatic portosystemic shunt (TIPS). Materials and Methods: A retrospective review of patients who underwent conventional TACE for HCC between January 2005 and December 2009 identified 10 patients with patent TIPS. From the same time period, 23 patients without TIPS were selected to control for comparable Model for End-Stage Liver Disease and Child-Pugh-Turcotte scores. The two groups showed similar distribution of Barcelona Clinic Liver Cancer and United Network of Organ Sharing stages. Target HCC lesions were evaluated according to the modified response evaluation criteria in solid tumors (mRECIST) guidelines. Transplantation rate, time to tumor progression, and overall survival (OS) were documented. Results: After TACE, the rate of complete response was significantly greater in non-TIPS patients compared with TIPS patients (74 vs. 30 %, p = 0.03). Objective response rate (complete and partial response) trended greater in the non-TIPS group (83 vs. 50 %, p = 0.09). The liver transplantation rate was 80 and 74 % in the TIPS and non-TIPS groups, respectively (p = 1.0). Time to tumor progression was similar (p = 0.47) between the two groups. OS favored the non-TIPS group (p = 0.01) when censored for liver transplantation. Conclusion: TACE is less effective in achieving complete or partial response using mRECIST criteria in TIPS patients compared with those without a TIPS. Nevertheless, similar clinical outcomes may be achieved, particularly in TIPS patients who are liver-transplantation candidates.

  5. Impact of Anatomical, Procedural, and Operator Skill Factors on the Success and Duration of Fluoroscopy-Guided Transjugular Intrahepatic Portosystemic Shunt

    SciTech Connect

    Marquardt, Steffen Rodt, Thomas Rosenthal, Herbert Wacker, Frank Meyer, Bernhard C.

    2015-08-15

    PurposeTo assess the impact of anatomical, procedural, and operator skill factors on the success and duration of fluoroscopy-guided transjugular intrahepatic portoystemic shunt following standard operating procedure (SOP).Material and MethodsDuring a 32-month period, 102 patients underwent transjugular intrahepatic portosystemic shunt creation (TIPS) by two interventional radiologists (IR) following our institutional SOP based on fluoroscopy guidance. Both demographic and procedural data were assessed. The duration of the intervention (D{sub Int}) and of the portal vein puncture (D{sub Punct}) was analyzed depending on the skill level of the IR as well as the anatomic or procedural factors.ResultsIn 99 of the 102 patients, successful TIPS without peri-procedural complications was performed. The mean D{sub Int} (IR1: 77 min; IR2: 51 min, P < 0.005) and the mean D{sub Punct} (IR1: 19 min; IR2: 13 min, P < 0.005) were significantly higher in TIPS performed by IR1 (with 2 years of clinical experience performing TIPS, n = 38) than by IR2 (>10 years of clinical experience performing TIPS, n = 61), (P < 0.005 both, Mann–Whitney U test). D{sub Int} showed a higher correlation with D{sub Punct} for IR2 (R{sup 2} = 0.63) than for IR1 (R{sup 2} = 0.13). There was no significant difference in the D{sub Punct} for both IRs with regard to the success of the wedged portography (P = 0.90), diameter of the portal vein (P = 0.60), central right portal vein length (P = 0.49), or liver function (MELD-Score before the TIPS procedure; P = 0.14).ConclusionTIPS following SOP is safe, fast, and reliable. The only significant factor for shorter D{sub Punct} and D{sub Int} was the clinical experience of the IR. Anatomic variability, successful portography, or liver function did not alter the duration or technical success of TIPS.

  6. Regenerative and fibrotic pathways in canine hepatic portosystemic shunt and portal vein hypoplasia, new models for clinical hepatocyte growth factor treatment

    PubMed Central

    Spee, Bart; Penning, Louis C; van den Ingh, Ted SGAM; Arends, Brigitte; IJzer, Jooske; van Sluijs, Frederik J; Rothuizen, Jan

    2005-01-01

    Background We analyzed two spontaneous dog diseases characterized by subnormal portal perfusion and reduced liver growth: (i) congenital portosystemic shunts (CPSS) without fibrosis and (ii) primary portal vein hypoplasia (PPVH), a disease associated with fibrosis. These pathologies, that lack inflammation or cholestasis, may represent simplified models to study liver growth and fibrosis. To investigate the possible use of those models for hepatocyte growth factor (HGF) treatment, we studied the functionality of HGF signaling in CPSS and PPVH dogs and compared this to aged-matched healthy controls. Results We used quantitative real-time polymerase chain reaction (Q-PCR) to analyze the mRNA expression of HGF, transforming growth factor β1 (TGF-β1), and relevant mediators in liver biopsies from cases with CPSS or PPVH, in comparison with healthy control dogs. CPSS and PPVH were associated with a decrease in mRNA expression of HGF and of MET proto-oncogene (c-MET). Western blot analysis confirmed the Q-PCR results and showed that intracellular signaling components (protein kinase B/Akt, ERK1/2, and STAT3) were functional. The TGF-β1 mRNA levels were unchanged in CPSS whereas there was a 2-fold increase in PPVH indicating an active TGF-β1 pathway, consistent with the observation of fibrosis seen in PPVH. Western blots on TGF-β1 and phosphorylated Smad2 confirmed an activated pro-fibrotic pathway in PPVH. Furthermore, Q-PCR showed an increase in the amount of collagen I present in PPVH compared to CPSS and control, which was confirmed by Western blot analysis. Conclusion The pathophysiological differences between CPSS and PPVH can adequately be explained by the Q-PCR measurements and Western blots. Although c-MET levels were reduced, downstream signaling seemed to be functional and provides a rational for HGF-supplementation in controlled studies with CPSS and PPVH. Furthermore both diseases may serve as simplified models for comparison with more complex chronic

  7. Transjugular intrahepatic portosystemic shunt (TIPS)

    MedlinePlus

    ... will ease pressure on the veins of your stomach, esophagus, intestines, and liver. ... Normally, blood coming from your esophagus, stomach, and ... of damage and there are blockages, blood cannot flow through it ...

  8. Transjugular Intrahepatic Portosystemic Shunt (TIPS)

    MedlinePlus Videos and Cool Tools

    ... to the contrast material used for venograms . Also, kidney failure (temporary or permanent) due to contrast material ... is a concern, particularly in patients with poor kidney function. Any procedure that involves placement of a ...

  9. Improved Patency of Transjugular Intrahepatic Portosystemic Shunt: The Efficacy of Cilostazol for the Prevention of Pseudointimal Hyperplasia in Swine TIPS Models

    SciTech Connect

    Park, Sang Woo Cha, In Ho; Kim, Chul Hwan; Jeon, Hae Jeong; Park, Jeong Hee; Hong, Suk Joo; Lee, In Sik

    2007-07-15

    Purpose. To investigate the efficacy of oral administration of cilostazol to inhibit pseudointimal/intimal hyperplasia in swine TIPS models. Methods. Successful TIPS creation was carried out in 11 of 12 healthy young pigs (20-25 kg). In the treatment group (n = 6), both cilostazol and aspirin were administered daily, from the first day of TIPS creation. The control group (n = 5) was administered only aspirin. The animals were followed-up for 2 weeks and then killed. The specimen (including portal vein, hepatic parenchymal tract, hepatic vein, and inferior vena cava) and stents were carefully bisected in a longitudinal fashion. The control group was compared with the treatment group by means of a gross and histologic evaluation of the degree of pseudointimal/intimal hyperplasia in the shunt. Results. At the gross evaluation, the control group showed considerably more pseudointimal/intimal hyperplasia than the treatment group. Using microscopic evaluation, there was a statistically significant difference (p < 0.05) in the mean maximum pseudointimal/intimal hyperplasia thickness between the control group (2.97 {+-} 0.33 mm) and treatment group (0.73 {+-} 0.27 mm). Conclusion. Oral administration of cilostazol may have been effective in reducing pseudointimal/intimal hyperplasia in swine TIPS models.

  10. Construction of Transjugular Intrahepatic Portosystemic Shunt: Bare Metal Stent/Stent-graft Combination versus Single Stent-graft, a Prospective Randomized Controlled Study with Long-term Patency and Clinical Analysis

    PubMed Central

    Wang, Chang-Ming; Li, Xuan; Fu, Jun; Luan, Jing-Yuan; Li, Tian-Run; Zhao, Jun; Dong, Guo-Xiang

    2016-01-01

    Background: Balanced adjustment of the portal vein shunt volume during a transjugular intrahepatic portosystemic shunt (TIPS) is critical for maintaining liver perfusion and decreasing the incidence of liver insufficiency. A stent-graft is proved to be superior to a bare metal stent (BMS) for the construction of a TIPS. However, the clinical results of the combination application of stents and stent-grafts have not been determined. This study aimed to compare the technique of using a combination of stents and stent-grafts with using a single stent-graft to construct a TIPS. Methods: From April 2011 to November 2014, a total of fifty patients were randomly assigned to a stents-combination group (Group I, n = 28) or a stent-graft group (Group II, n = 22). Primary patency rates were calculated. Clinical data, including the technical success rate, bleeding control results, incidence of encephalopathy, liver function preservation, and survival rate, were assessed. Results: Technically, the success rate was 100% for both groups. The primary patency rates at 1, 2, and 3 years for Group I were 96%, 84%, and 77%, respectively; for Group II, they were 90%, 90%, and 78%, respectively. The survival rates at 1, 2, and 3 years for Group I were 79%, 74%, and 68%, respectively; for Group II, they were 82%, 82%, and 74%, respectively. The incidence of hepatic encephalopathy was 14.3% for Group I and 13.6% for Group II. The Child-Pugh score in Group I was stable at the end of the follow-up but had significantly increased in Group II (t = −2.474, P = 0.022). Conclusions: The construction of a TIPS with either the single stent-graft or BMS/stent-graft combination is effective for controlling variceal bleeding. The BMS/stent-graft combination technique is superior to the stent-graft technique in terms of hepatic function preservation indicated by the Child-Pugh score. However, considering the clinical results of the TIPS, the two techniques are comparable in their primary shunt

  11. A retrospective analysis of the impact of diastolic dysfunction on one-year mortality after transjugular intrahepatic porto-systemic shunt, liver transplantation and non-transplant abdominal surgery in patients with cirrhosis

    PubMed Central

    Shounak, Majumder; Vimal, Rabdiya; Colin, Swales; David I, Silverman

    2015-01-01

    Background The incidence of diastolic dysfunction (DD) approaches 40% in patients with cirrhosis. However, the clinical impact of DD remains a subject of considerable debate. Surgery in patients with cirrhosis is innately hazardous. Diastolic heart failure has been linked to increased mortality after transjugular intrahepatic porto-systemic shunt surgery (TIPSS). To date, none of the commonly accepted preoperative risk assessment models applied to patients with liver disease incorporates DD. We aimed to examine the relationship between DD and postoperative outcomes in patients with cirrhosis undergoing abdominal surgery. Methods Patients with cirrhosis who underwent abdominal surgery between January 2000 and December 2011 were included if they had preoperative echocardiography done within 3 months of surgery. The echocardiographic images were reviewed using flow and tissue Doppler techniques to identify the presence of DD. Outcomes analyzed included one-year mortality and postoperative complications. Results A total of 140 patients were included in the study of which 63 patients (45%) met pre-established criteria for DD. Those with DD were older (P < 0.005) and less likely to have an isolated viral etiology of cirrhosis (P<0.05). The one-year mortality rate was 22.2% (14/63) in patients with DD and 20.8% (16/77) in those without DD (P=0.42). Postoperative complications were not statistically different in the two groups. Conclusion DD is common in patients with cirrhosis. In patients with cirrhosis undergoing TIPS and/or abdominal surgery, the presence of DD does not increase post-procedure complications or one-year mortality. PMID:26129720

  12. Early Liver Failure after Transjugular Intrahepatic Portosystemic Shunt in Patients with Cirrhosis with Model for End-Stage Liver Disease Score of 12 or Less: Incidence, Outcome, and Prognostic Factors.

    PubMed

    Luca, Angelo; Miraglia, Roberto; Maruzzelli, Luigi; D'Amico, Mario; Tuzzolino, Fabio

    2016-08-01

    Purpose To evaluate the incidence, outcomes, and prognostic factors of early liver failure (ELF) after transjugular intrahepatic portosystemic shunt (TIPS) creation in patients with cirrhosis with Model for End-Stage Liver Disease (MELD) score of 12 or less. Materials and Methods Institutional review board approved this retrospective study, with waiver of written informed consent. Two-hundred sixteen consecutive patients with cirrhosis (140 men, 76 women; mean age, 55.9 years; virus-related cirrhosis, 67.6% [146 of 216 patients]) with baseline MELD score of 12 or less who underwent TIPS placement between September 1999 and July 2012 were followed until last clinical evaluation, liver transplantation, or death. The Kaplan-Meier method, log-rank test, area under the receiver operating characteristic curve, and univariate and multivariate analyses were used, as appropriate. Results Twenty of 216 patients (9.2%) developed ELF within 3 months of TIPS (10 patients died, one required liver transplantation, and nine increased the MELD score to >18). ELF was associated with lower survival, 37% versus 95% at 6 months, and 24% versus 86% at 12 months (P < .001) compared with patients without ELF. ELF occurred in 16 of 95 (16.8%) patients with refractory ascites and in four of 121 (3.3%) patients with other indications for TIPS. Multivariate analysis confirmed MELD scores of 11 or 12 (odds ratio, 3.96 [95% confidence interval: 1.07, 14.67]; P = .040), decreased hemoglobin level (odds ratio, 0.68 [95% confidence interval: 0.49, 0.95]; P = .022), and decreased platelet count (odds ratio, 0.99 [95% confidence interval: 0.99, 0.99]; P = .024) as predictors for ELF in patients with refractory ascites. Conclusion ELF is not uncommon in cirrhotic patients with a MELD score of 12 or less who undergo TIPS placement for refractory ascites (especially in patients with MELD of 11 or 12) and decreased hemoglobin level and platelet count. (©) RSNA, 2016. PMID:26982564

  13. Colectomy for Porto-Systemic Encephalopathy: Is it Still Topical?

    PubMed

    Ennaifer, Rym; Hayfa, Romdhane; Hefaiedh, Rania; Marsaoui, Lobna; Hadj, Najet Bel; Khalfallah, Tahar

    2013-01-25

    Hepatic encephalopathy (HE) is a common long term complication of porto-systemic shunt. We report herein the case of a 59-year-old man with Child-Pugh A cirrhosis treated successfully 9 years earlier with distal splenorenal shunt for uncontrolled variceal bleeding. In the last year, he developed a severe and persistent hepatic encephalopathy secondary to the shunt, which was resistant to medical therapy. As liver transplantation was not available and obliteration of the shunt was hazardous, we performed subtotal colectomy in order to reduce ammonia production. This therapeutic option proved successful, as the grade of encephalopathy decreased and the patient improved. Our experience indicates that colonic exclusion should be considered as an option in the management of HE refractory to medical treatment in highly selected patients when liver transplantation is not available or even as a bridge given the long waiting time on lists. PMID:24765497

  14. Post-TIPS Hepatic Encephalopathy Treated by Occlusion Balloon-Assisted Retrograde Embolization of a Coexisting Spontaneous Splenorenal Shunt

    SciTech Connect

    Shioyama, Yasukazu; Matsueda, Kiyoshi; Horihata, Koushi; Kimura, Masashi; Nishida, Norifumi; Kishi, Kazushi; Terada, Masaki; Sato, Morio; Yamada, Ryusaku

    1996-11-15

    A 51-year-old man with posthepatitis cirrhosis underwent a transjugular intrahepatic portosystemic shunt (TIPS) for bleeding of recurrent esophageal varices. The patient had a coexisting, spontaneous, splenorenal shunt. He subsequently developed hepatic encephalopathy, presumably due to excessive portosystemic shunting. Since medical management resulted in no significant improvement, the splenorenal shunt was embolized from the jugular vein approach via renal vein access during temporary balloon occlusion. Within a few days, the patient's hepatic encephalopathy resolved. Twelve months later the patient showed no recurrence of encephalopathy and had maintained a patent TIPS.

  15. MRI-Monitored Intra-Shunt Local Agent Delivery of Motexafin Gadolinium: Towards Improving Long-Term Patency of TIPS

    PubMed Central

    Meng, Yanfeng; Zhang, Tong; Willis, Patrick; Le, Thomas; Soriano, Stephanie; Ray, Erik; Valji, Karim; Zhang, Guixiang; Yang, Xiaoming

    2013-01-01

    Background Transjugular intrahepatic portosystemic shunt (TIPS) has become an important and effective interventional procedure in treatment of the complications related to portal hypertension. Although the primary patency of TIPS has been greatly improved due to the clinical application of cover stent-grafts, the long-term patency is still suboptimal. This study was to investigate the feasibility of using magnetic resonance imaging (MRI)-monitored intra-shunt local agent delivery of motexafin gadolinium (MGd) into shunt-vein walls of TIPS. This new technique aimed to ultimately inhibit shuntstenosis of TIPS. Methodology Human umbilical vein smooth muscle cells (SMCs) were incubated with various concentrations of MGd, and then examed by confocal microscopy and T1-map MRI. In addition, the proliferation of MGd-treated cells was evaluated. For in vivo validation, seventeen pigs underwent TIPS. Before placement of the stent, an MGd/trypan-blue mixture was locally delivered, via a microporous balloon, into eleven shunt-hepatic vein walls under dynamic MRI monitoring, while trypan-blue only was locally delivered into six shunt-hepatic vein walls as serve as controls. T1-weighted MRI of the shunt-vein walls was achieved before- and at different time points after agent injections. Contrast-to-noise ratio (CNR) of the shunt-vein wall at each time-point was measured. Shunts were harvested for subsequent histology confirmation. Principal Findings In vitro studies confirmed the capability of SMCs in uptaking MGds in a concentration-dependent fashion, and demonstrated the suppression of cell proliferation by MGds as well. Dynamic MRI displayed MGd/blue penetration into the shunt-vein walls, showing significantly higher CNR of shunt-vein walls on post-delivery images than on pre-delivery images (49.5±9.4 vs 11.2±1.6, P<0.01), which was confirmed by histology. Conclusion Results of this study indicate that MRI-monitored intra-shunt local MGd delivery is feasible and MGd

  16. Bilhemia: A Rare Complication of Transjugular Intraheptic Portosytemic Shunt

    PubMed Central

    Zhang, Michael

    2015-01-01

    A 56-year-old woman with cirrhosis due to chronic hepatitis C underwent emergent transjugular intrahepatic portosystemic shunt (TIPS) due to a ruptured esophageal varix during esophagogastroduodenoscopy. Following TIPS, the patient experienced a rapid rise in serum bilirubin with no evidence of biliary obstruction or hepatic injury. She was determined to have bilhemia, a rare but serious complication of TIPS. PMID:26504882

  17. Direct measurement of porto-systemic gradient in a failing Fontan circulation.

    PubMed

    Velpula, Madhavi; Sheron, Nick; Guha, Neill; Salmon, Tony; Hacking, Nigel; Veldtman, Gruschen R

    2011-01-01

    We describe the case history of a 42-year-old man with cardiac cirrhosis, portal hypertension, and life-threatening variceal bleeding after Fontan revision surgery. Direct pressure measurements in the portal vein, though high, demonstrated only a modest portosystemic gradient (PSG), 9 mm Hg. A transjugular intrahepatic portosystemic shunt procedure was performed. This reduced the PSG (3 mm Hg). His bleeding was controlled. The patient's histopathological findings were identical to that previously documented in Fontan patients, raising the question of whether these subdiaphragmatic hemodynamics are representative of the broader failing Fontan population. PMID:21356034

  18. Restoration of Liver Function and Portosystemic Pressure Gradient after TIPSS and Late TIPSS Occlusion

    SciTech Connect

    Maedler, U.; Hansmann, J.; Duex, M.; Noeldge, G.; Sauer, P.; Richter, G.M.

    2002-03-15

    TIPSS (transjugular intrahepatic portosystemic shunt) may be indicated to control bleeding from esophageal and gastric varicose veins, to reduce ascites, and to treat patients with Budd-Chiari syndrome and veno-occlusive disease. Numerous measures to improve the safety and methodology of the procedure have helped to increase the technical and clinical success. Follow-up of TIPSS patients has revealed shunt stenosis to occur more often in patients with preserved liver function (Child A, Child B). In addition, the extent of liver cirrhosis is the main factor that determines prognosis in the long term. Little is known about the effects of TIPSS with respect to portosystemic hemodynamics. This report deals with a cirrhotic patient who stopped drinking 7 months prior to admission. He received TIPSS to control ascites and recurrent esophageal bleeding. Two years later remarkable hypertrophy of the left liver lobe and shunt occlusion was observed. The portosystemic pressure gradient dropped from 24 mmHg before TIPSS to 11 mmHg and remained stable after shunt occlusion. The Child's B cirrhosis prior to TIPSS turned into Child's A cirrhosis and remained stable during the follow-up period of 32 months. This indicates that liver function of TIPSS patients may recover due to hypertrophy of the remaining non-cirrhotic liver tissue. In addition the hepatic hemodynamics may return to normal. In conclusion, TIPSS cannot cure cirrhosis but its progress may be halted if the cause can be removed. This may result in a normal portosystemic gradient, leading consequently to shunt occlusion.

  19. Blood ammonia levels in liver cirrhosis: a clue for the presence of portosystemic collateral veins

    PubMed Central

    2009-01-01

    Background Portal hypertension leads to the formation of portosystemic collateral veins in liver cirrhosis. The resulting shunting is responsible for the development of portosystemic encephalopathy. Although ammonia plays a certain role in determining portosystemic encephalopathy, the venous ammonia level has not been found to correlate with the presence or severity of this entity. So, it has become partially obsolete. Realizing the need for non-invasive markers mirroring the presence of esophageal varices in order to reduce the number of endoscopy screening, we came back to determine whether there was a correlation between blood ammonia concentrations and the detection of portosystemic collateral veins, also evaluating splenomegaly, hypersplenism (thrombocytopenia) and the severity of liver cirrhosis. Methods One hundred and fifty three consecutive patients with hepatic cirrhosis of various etiologies were recruited to participate in endoscopic and ultrasonography screening for the presence of portosystemic collaterals mostly esophageal varices, but also portal hypertensive gastropathy and large spontaneous shunts. Results Based on Child-Pugh classification, the median level of blood ammonia was 45 mcM/L in 64 patients belonging to class A, 66 mcM/L in 66 patients of class B and 108 mcM/L in 23 patients of class C respectively (p < 0.001). The grade of esophageal varices was concordant with venous ammonia levels (rho 0.43, p < 0.001). The best area under the curve was given by ammonia concentrations, i, e., 0.78, when comparing areas of ammonia levels, platelet count and spleen longitudinal diameter at ultrasonography. Ammonia levels predicted hepatic decompensation and ascites presence (Odds Ratio 1.018, p < 0.001). Conclusion Identifying cirrhotic patients with high blood ammonia concentrations could be clinically useful, as high levels would lead to suspicion of being in presence of collaterals, in clinical practice of esophageal varices, and pinpoint those

  20. [Early transjugular intrahepatic portosystemic shunt: When, how and in whom?].

    PubMed

    Ruiz-Blard, Esteban; Baiges, Anna; Turon, Fanny; Hernández-Gea, Virginia; García-Pagán, Juan Carlos

    2016-01-01

    Early TIPS is basically a new application of an old concept. This intervention used to be a useful rescue therapy when other interventions failed but has now become a primary intervention in patients with variceal bleeding and risk factors for poor prognosis. This technique has also been proven to control bleeding and has a definite survival advantage at 6 weeks and 1 year over standard therapy with vasoactive drugs and endoscopy, without increasing the rate of adverse events. In well-trained hands and with appropriate candidate selection, early TIPS is a safe, life-saving and evidenced-based procedure. PMID:26610770

  1. Comparison of shunt fraction estimation using transcolonic iodine-123-iodoamphetamine and technetium-99m-pertechnetate in a group of dogs with experimentally-induced chronic biliary cirrhosis

    SciTech Connect

    Koblik, P.D.; Hornof, W.J.; Yen, C.K.; Komtebedde, J.; Breznock, E.; Fisher, P. )

    1991-01-01

    Portosystemic shunt fraction estimation using transcolonic iodine-123-iodoamphetamine (IMP) has been previously validated relative to portal vein macroaggregated albumin injections using an experimental model of cirrhosis. Transcolonic technetium-99m-pertechnetate (TcO4-) has been proposed as an alternative tracer to IMP to study portal circulation in cirrhotic patients. We compared shunt fraction estimates from paired transcolonic IMP and TcO4- studies performed on a group of dogs before and after common bile duct ligation surgery. Pertechnetate over-estimated shunt fraction in 6/7 postoperative studies relative to IMP. A good correlation between the two methods was demonstrated, however, the slope of the regression line was substantially less than 1.0 with TcO4- values reaching 100% at IMP shunt values of approximately 60%. This apparent inability to accurately assess high shunt flows may limit the quantitative aspects of TcO4- studies on patients with severe portosystemic shunting.

  2. Combination treatment of transjugular retrograde obliteration and endoscopic embolization for portosystemic encephalopathy with esophageal varices.

    PubMed

    Chikamori, Fumio; Kuniyoshi, Nobutoshi; Shibuya, Susumu; Takase, Yasuhiro

    2004-01-01

    The treatment of chronic portosystemic encephalopathy with esophageal varices has not yet been established. We were able to control a case of chronic portosystemic encephalopathy with esophageal varices using a combination treatment of transjugular retrograde obliteration and endoscopic embolization. A 57-year-old man came to our hospital in a confused, apathetic and tremulous state. The grade of encephalopathy was II. The plasma ammonia level was abnormally elevated to 119 microg/dL, and the ICGR15 was 59%. Endoscopic examination revealed nodular esophageal varices with cherry-red spots. There were no gastric varices. Ultrasonography and CT revealed liver cirrhosis with a splenorenal shunt. We first applied endoscopic embolization for the esophageal varices before transjugular retrograde obliteration. We injected 5% ethanolamine oleate with iopamidol retrogradely into the esophageal varices and their associated blood routes under fluoroscopy and obliterated the palisade vein, the cardiac venous plexus and left gastric vein. Transjugular retrograde obliteration was performed 14 days after endoscopic embolization. Retrograde shunt venography visualized the splenorenal shunt and communicating route to the retroperitoneal vein. There was no communicating route to the azygos vein. After obliteration of the communicating route to the retroperitoneal vein with absolute ethanol, 5% ethanolamine oleate with iopamidol was injected into the splenorenal shunt as far as the root of the posterior gastric vein. After transjugular retrograde obliteration, the encephalopathy improved to grade 0 even without the administration of lactulose and branched-chain amino acid. The plasma ammonia level and ICGR15 were reduced to 62 microg/dL and 26%. We conclude that combination treatment of transjugular retrograde obliteration and endoscopic embolization is a rational, effective and safe treatment for chronic portosystemic encephalopathy complicated with esophageal varices. PMID:15362757

  3. Distal splenorenal shunt

    MedlinePlus

    ... shunt procedure; Renal - splenic venous shunt; Warren shunt; Cirrhosis - distal splenorenal; Liver failure - distal splenorenal ... hepatitis Blood clots Certain congenital disorders Primary biliary cirrhosis When blood cannot flow normally through the portal ...

  4. Characterization of uncommon portosystemic collateral circulations in patients with hepatic cirrhosis.

    PubMed

    Wu, Qin; Shen, Lijun; Chu, Jindong; Ma, Xuemei; Jin, Bo; Meng, Fanping; Chen, Jinpin; Wang, Yanling; Wu, Libing; Han, Jun; Zhang, Wenhui; Ma, Wei; Wang, Huaming; Li, Hanwei

    2015-01-01

    The purpose of the present study was to characterize uncommon portosystemic collateral circulation in hepatic cirrhosis. Portosystemic uncommon collateral circulation (UCC) was detected, characterized and evaluated by a combination of spiral computed tomography angiography, three-dimensional imaging angiography and electronic gastroscopy in patients diagnosed with hepatic cirrhosis. In total, 118 cases with UCC were detected from a pool of 700 hepatic cirrhosis patients with portal hypertension. The incidence was 16.86% and included cases with splenic-renal, gastro-renal, paravertebral, retroperitoneal, gastric-splenic and cardio-phrenic angle vein shunts. The occurrence rate of UCC formation increased with the Child-Pugh grade. Compared with common collateral circulations, the incidence of severe esophageal or gastric fundus varicose veins, severe portal hypertensive gastropathy and the incidence of a large quantity of ascites was much lower in the patients with UCC (P<0.01), whereas the incidence of hepatic encephalopathy and chronic elevated blood ammonia levels was significantly higher (P<0.01). The incidence of uncommon portosystemic collateral circulation is extremely common in patients with liver cirrhosis and is associated with the Child-Pugh grades of hepatic function. UCC can aid in the relief of the complications derived from portal hypertension, but it may increase the incidence of hepatic encephalopathy and chronic elevated blood ammonia levels. PMID:25435990

  5. Percutaneous Mesocaval Shunt Creation in a Patient with Chronic Portal and Superior Mesenteric Vein Thrombosis

    SciTech Connect

    Bercu, Zachary L. Sheth, Sachin B.; Noor, Amir; Lookstein, Robert A. Fischman, Aaron M. Nowakowski, F. Scott Kim, Edward Patel, Rahul S.

    2015-10-15

    The creation of a transjugular intrahepatic portosystemic shunt (TIPS) is a critical procedure for the treatment of recurrent variceal bleeding and refractory ascites in the setting of portal hypertension. Chronic portal vein thrombosis remains a relative contraindication to conventional TIPS and options are limited in this scenario. Presented is a novel technique for management of refractory ascites in a patient with hepatitis C cirrhosis and chronic portal and superior mesenteric vein thrombosis secondary to schistosomiasis and lupus anticoagulant utilizing fluoroscopically guided percutaneous mesocaval shunt creation.

  6. Ventriculomammary shunt: an unusual ventriculoperitoneal shunt complication.

    PubMed

    Chaudhry, Nauman S; Johnson, Jeremiah N; Morcos, Jacques J

    2015-02-01

    Ventriculoperitoneal (VP) shunt malfunctions are common and can result in significant consequences for patients. Despite the prevalence of breast augmentation surgery and breast surgery for other pathologies, few breast related VP shunt complications have been reported. A 54-year-old woman with hydrocephalus post-subarachnoid hemorrhage returned 1 month after VP shunt placement complaining of painful unilateral breast enlargement. After investigation, it was determined that the distal VP shunt catheter had migrated from the peritoneal cavity into the breast and wrapped around her breast implant. The breast enlargement was the result of cerebrospinal fluid retention. We detail this unusual case and review all breast related VP shunt complications reported in the literature. To avoid breast related complications related to VP shunt procedures, it is important to illicit pre-procedural history regarding breast implants, evade indwelling implants during catheter tunneling and carefully securing the abdominal catheter to prevent retrograde catheter migration to the breast. PMID:25127261

  7. Complications of denver shunt.

    PubMed

    Perera, Eranga; Bhatt, Shweta; Dogra, Vikram S

    2011-01-01

    Hepatic hydrothorax secondary to transdiaphragmatic spread of peritoneal fluid can cause respiratory discomfort to the patient. Draining of hydrothorax helps relieve these symptoms. Pleurovenous shunt (Denver shunt) is a relatively non-invasive method of shunting the pleural fluid to the central venous system. Reported complications of pleurovenous shunts are shunt failure, pulmonary edema, post shunt coagulopathy, deep vein thrombosis, and infection. We report a rare case of a leak at the venous end of the catheter that was placed within the right internal jugular vein, resulting in a large collection in the neck. PMID:21915387

  8. Successful living donor liver transplant in a child with Abernethy malformation with biliary atresia, ventricular septal defect and intrapulmonary shunting.

    PubMed

    Singhal, Ashish; Srivastava, Ajitabh; Goyal, Neerav; Vij, Vivek; Wadhawan, Manav; Bera, Motilal; Gupta, Subash

    2009-12-01

    Congenital portosystemic shunts are the anomalies in which the mesenteric venous drainage bypasses the liver and drains directly into the systemic circulation. This is a report of a rare case of LDLT in a four-yr old male child suffering with biliary atresia (post-failed Kasai procedure) associated with (i) a large congenital CEPSh from the spleno-mesentric confluence to the LHV, (ii) intrapulmonary shunts, (iii) perimembranous VSD. The left lobe graft was procured from the mother of the child. Recipient IVC and the shunt vessel were preserved during the hepatectomy, and the caval and shunt clamping were remarkably short while performing the HV and portal anastomosis. Post-operative course was uneventful; intrapulmonary shunts regressed within three months after transplantation and currently after 18 months following transplant child is doing well with normal liver functions. CEPSh has been extensively discussed and all the published cases of liver transplantation for CEPSh were reviewed. PMID:19254272

  9. Ventriculoperitoneal shunt - discharge

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000149.htm Ventriculoperitoneal shunt - discharge To use the sharing features on this ... JavaScript. Your child has hydrocephalus and needed a shunt placed to drain excess fluid and relieve pressure ...

  10. [Shunt and short circuit].

    PubMed

    Rangel-Abundis, Alberto

    2006-01-01

    Shunt and short circuit are antonyms. In French, the term shunt has been adopted to denote the alternative pathway of blood flow. However, in French, as well as in Spanish, the word short circuit (court-circuit and cortocircuito) is synonymous with shunt, giving rise to a linguistic and scientific inconsistency. Scientific because shunt and short circuit made reference to a phenomenon that occurs in the field of the physics. Because shunt and short circuit are antonyms, it is necessary to clarify that shunt is an alternative pathway of flow from a net of high resistance to a net of low resistance, maintaining the stream. Short circuit is the interruption of the flow, because a high resistance impeaches the flood. This concept is applied to electrical and cardiovascular physiology, as well as to the metabolic pathways. PMID:17257492

  11. Percutaneous Transjugular Direct Porto-caval Shunt in Patients with Budd-Chiari Syndrome

    SciTech Connect

    Quateen, A.; Pech, M.; Berg, T.; Bergk, A.; Podrabsky, P.; Felix, R.; Ricke, J.

    2006-08-15

    The purpose of the study was to evaluate the feasibility and effectiveness of direct porto-caval shunts in patients with Budd-Chiari syndrome (BCS) in whom there is no access to the hepatic veins during transjugular intrahepatic portosystemic shunt (TIPSS). We included six consecutive patients with fulminant/acute Budd-Chiari syndrome (mean age: 35 years) in whom a conventional TIPSS was not possible due to inaccessible hepatic veins. We performed a direct porto-caval shunt via a transhepatic approach. Patients were followed up by means of clinical examination, laboratory investigations, and Doppler ultrasound. TIPSS implantation from the inferior vena cava (IVC) was successful in all six patients (100%). The median transhepatic shunt length was 9 cm (8-10 cm). No procedure-related complications were observed in our patients. Early shunt occlusion occurred in three out of six patients (50%). In all three of these patients, the stent used to stabilize the shunt ended 1-2 cm before reaching the IVC. All occlusions were successfully recanalized. One of these patients developed recurrent early shunt as well as mesenteric and splenic vein occlusions. She died 7 days after TIPSS placement due to an unmanageable coagulation disorder. The remaining five patients were followed up by planned clinical examination and laboratory investigations (mean follow-up time was 15 months; patient 1 was followed up for 13 months, patient 2 for 14 months, patient 3 for 15 months, and patients 4 and 5 for 16 months) and all displayed a complete and durable resolution of liver failure and ascites without reintervention. In patients with acute liver failure originating from BCS and inaccessible hepatic veins, a direct transhepatic porto-caval shunt can be performed safely and effectively under ultrasound guidance. Future studies in larger patient groups should investigate if the patency of transcaval TIPSS with long transhepatic shunt segments is similar compared to conventional TIPSS via

  12. Distal splenorenal shunt

    MedlinePlus

    ... transjugular intrahepatic portal systematic shunt for variceal bleeding: a randomized trial. Gastroenterology. 2006;130(6):1643-51. Sicklick JK, D'Angelica M, Fong Y. The liver. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, ...

  13. Hydrocephalus and Shunts

    MedlinePlus

    ... or anesthesia. When ventricles start to get too big, it is a strong sign that the shunt is not working right. It is important to know that some people (between 5 and 15 percent) with Spina Bilda may have ...

  14. Shunt tube calcification as a late complication of ventriculoperitoneal shunting.

    PubMed

    Salim, Abubakr Darrag; Elzain, Mohammed Awad; Mohamed, Haddab Ahmed; Ibrahim Zayan, Baha Eldin Mohamed

    2015-01-01

    Shunt calcification is a rare complication of ventriculoperitoneal shunting that occurs years later after the initial operation this condition is rarely reported in literature. Two patients with shunt calcifications were described. The first patient was 17-year-old lady who had congenital hydrocephalus and shunted in the early infancy, she was presented recently complaining of itching of the skin along the shunt track and limitation of neck movement. The patient was then operated with removal of the old peritoneal catheter and replacing it with a new one. The second patient was 17-year-old boy originally was a case of posterior fossa pilocytic astrocytoma associated with obstructive hydrocephalus, he was operated with both shunting for the hydrocephalus and tumor removal, 6 years later he presented with shunt exposure. Calcification of the shunt tube was discovered intraoperatively upon shunt removal. Shunt calcification has been observed mainly in barium-impregnated catheters. Introducing plain silicone-coated shunt tubing may reduce the rate of this condition. The usual complaints of the patients suffering from this condition are pain in the neck and chest wall along the shunt pathway and limitation of the neck movement due to shunt tube tethering, but features of shunt dysfunction and skin irritation above the shunt may be present. In this review, plain X-ray and operative findings showed that the most extensive calcification is present in the neck, where the catheters were subject to heavy mechanical stress. Disturbed calcium and phosphate metabolisms may be involved in this condition. Shunt calcification is a rare condition that occurs due to material aging presenting with features of shunt tethering, dysfunction or overlying skin irritation. Plain X-ray is needed to detect calcification while shunt removal, replacement or endoscopic third ventriculostomy may carry solution for this condition. PMID:26396620

  15. Acute TIPS occlusion due to iatrogenic arteriovenous shunt in a cirrhotic patient with total portal vein thrombosis

    PubMed Central

    Hatzidakis, Adam; Kouroumalis, Elias; Kehagias, Elias; Digenakis, Emmanuel; Samonakis, Dimitrios; Tsetis, Dimitrios

    2015-01-01

    A 69-year-old man with portal hypertension was admitted with decompensated alcoholic cirrhosis and diuretic resistant ascites. Ultrasound revealed partial portal thrombosis. Due to diuretic intolerance, transjugular intrahepatic portosystemic shunt (TIPS) was decided during which a hepatic arterial branch was inadvertently catheterized. Finally, TIPS was created, but the patient continued gaining weight. Color-Doppler ultrasonography (CDUS) showed upper stent part patency with absence of flow in lower stent portion. Twenty-five days later, the patient presented melena. Endoscopy revealed blood emerging from the Vater papilla. Hepatic angiography revealed arteriovenous shunt between a hepatic arterial branch and the proximal part of the TIPS shunt. Covered stent placement restored sufficient TIPS flow. The patient deteriorated and died 1 month later. We found out that our major technical drawback was that we did not inject a small amount of contrast after puncturing the supposed portal vein, in order to confirm correct position of the needle. PMID:26767123

  16. Aqueous shunts for glaucoma

    PubMed Central

    Minckler, Don; Vedula, Satyanarayana S; Li, Tianjing; Mathew, Milan; Ayyala, Ramesh; Francis, Brian

    2014-01-01

    Background Aqueous shunts are employed for intraocular pressure (IOP) control in primary and secondary glaucomas that fail medical, laser, and other surgical therapies. Objectives This review compares aqueous shunts for IOP control and safety. Search strategy We searched CENTRAL, MEDLINE, PubMed, EMBASE, NRR in January 2006, LILACS to February 2004 and reference lists of included trials. Selection criteria We included all randomized and quasi-randomized trials in which one arm of the study involved shunts. Data collection and analysis Two authors independently extracted data for included studies and a third adjudicated discrepancies. We contacted investigators for missing information. We used fixed-effect models and summarized continuous outcomes using mean differences. Main results We included fifteen trials with a total of 1153 participants with mixed diagnoses. Five studies reported details sufficient to verify the method of randomization but only two had adequate allocation concealment. Data collection and follow-up times were variable. Meta-analysis of two trials comparing Ahmed implant with trabeculectomy found trabeculectomy resulted in lower mean IOPs 11 to 13 months later (mean difference 3.81 mm Hg, 95% CI 1.94 to 5.69 mm Hg). Meta-analysis of two trials comparing double-plate Molteno implant with the Schocket shunt was not done due to substantial heterogeneity. One study comparing ridged with standard double-plate Molteno implants found no clinically significant differences in outcome. Two trials investigating the effectiveness of adjunctive mitomycin (MMC) with the Molteno and Ahmed implants found no evidence of benefit with MMC. Two trials that investigated surgical technique variations with the Ahmed found no benefit with partial tube ligation or excision of Tenon's capsule. One study concluded there were outcome advantages with a double versus a single-plate Molteno implant and one trial comparing the 350 mm2 and 500 mm2 Baerveldt shunts found no

  17. Anatomy of the Portal Vein Bifurcation: Implication for Transjugular Intrahepatic Portal Systemic Shunts

    SciTech Connect

    Kwok, Philip Chong-hei Ng, Wai Fu; Lam, Christine Suk-yee; Tsui, Polly Po; Faruqi, Asma

    2003-06-15

    Purpose: The relationship of the portalvein bifurcation to the liver capsule in Asians, which is an important landmark for transjugular intrahepatic portosystemic shunt, has not previously been described. Methods: The anatomy of the portal vein bifurcation was studied in 70 adult Chinese cadavers; it was characterized as intrahepatic or extrahepatic. The length of the exposed portion of the right and left portal veins was measured when the bifurcation was extrahepatic. Results: The portal vein bifurcation was intrahepatic in 37 cadavers (53%) and extrahepatic in 33 cadavers (47%). The mean length of the right and left extrahepatic portal veins was 0.96 cm and 0.85 cm respectively.Both were less than or equal to 2 cm in 94% of the cadavers with extrahepatic bifurcation. There was no correlation between the presence of cirrhosis and the location of the portal vein bifurcation(p 1.0). There was no statistically significant difference in liver mass in cadavers with either extrahepatic or intrahepatic bifurcation (p =0.40). Conclusions: These findings suggest that fortransjugular intrahepatic portosystemic shunt placement, a portal vein puncture 2 cm from the bifurcation will be safe in most cases.

  18. Ductal Plate Malformation in the Liver of Boxer Dogs: Clinical and Histological Features.

    PubMed

    Pillai, S; Center, S A; McDonough, S P; Demarco, J; Pintar, J; Henderson, A K; Cooper, J; Bolton, T; Sharpe, K; Hill, S; Benedict, A G; Haviland, R

    2016-05-01

    Ductal plate malformations (DPMs) represent developmental biliary disorders with a wide phenotypic spectrum. This study characterizes DPM in 30 Boxer dogs. Median age was 1.5 (range, 0.3-10.0) years, with 12 dogs <1 year. Clinical features included increased serum levels of liver enzymes (28), gastrointestinal signs (16), poor body condition (14), abdominal effusion (9), and hepatic encephalopathy (2). Additional malformations included gallbladder atresia (8), atrophied left liver (2), absent quadrate lobe with left-displaced gallbladder (1), portal vasculature atresia (left liver, 1), intrahepatic portosystemic shunt (1), and complex intrahepatic arteriovenous malformation (1). All dogs had portal tracts dimensionally expanded by a moderate-to-severe multiple small bile duct phenotype embedded in abundant extracellular matrix; 80% displayed variable portal-to-portal bridging. Quantitative analysis confirmed significantly increased fibrillar collagen and a 3-fold increased portal tract area relative to 6 Boxer and 10 non-Boxer controls. Biliary phenotype was dominated by tightly formed CK19-positive ductules, typically 10 to 15 μm in diameter, with 3 to >30 profiles per portal tract, reduced luminal apertures, and negative Ki-67 immunoreactivity. CK19-positive biliary epithelium intersected directly with zone 1 hepatocytes as a signature feature when considered with other DPM characteristics. Phenotypic variation included a multiple small bile duct phenotype (all dogs), predominantly thin-walled sacculated ducts (4), well-formed saccular ducts (4), and sacculated segmental, interlobular, and intralobular ducts (Caroli malformation, 2 dogs, one with bridging portal fibrosis). Histologic evidence of portal venous hypoperfusion accompanied increased biliary profiles in every case. We propose that this spectrum of disorders be referred to as DPM with appropriate modifiers to characterize the unique phenotypes. PMID:26797094

  19. Insufficient Portal Vein Inflow in Children without Major Shunt Vessels During Living Donor Liver Transplantation.

    PubMed

    Matsuura, Toshiharu; Yoshimaru, Koichiro; Yanagi, Yusuke; Esumi, Genshiro; Hayashida, Makoto; Taguchi, Tomoaki

    2016-01-01

    BACKGROUND Liver cirrhosis is frequently accompanied by insufficient portal vein inflow (IPVF) with large portosystemic shunts. However, pediatric cases often manifested IPVF without any apparent major portosystemic shunts. Although IPVF is a very critical issue, the intraoperative assessment has not been well established. In this study, we reviewed the intraoperative approach and the outcome of the IPVF cases at our department. MATERIAL AND METHODS Eighty-three living donor liver transplantations (LDLT) were performed from 1996 to 2014. The IPVF occurred in 5 cases and necessitated some additional assessments and intraoperative PV flow modulations. We retrospectively reviewed the operative records and analyzed the risk factors and the outcome of the IPVF. RESULTS All 5 IPVF cases were biliary atresia and the mean age at LDLT was 0.74±0.19 years old. The mean recipient PV diameter was 4.3±0.8 mm and the donor IMV patch grafts were applied. To increase the PV inflow, the collaterals around the spleen were ligated in all cases. Intraoperative portal venography was performed in 1 case for selective shunt vessel ligation. In 1 case, the graft was removed and returned to the back table to prevent graft loss during the IPVF. As a result, the final PVF/GV increased to 66.4±20.0 ml/min/100 g. CONCLUSIONS IPVF is a very critical problem. Intraoperative portal venography is helpful and collateral veins ligation is crucial. In some cases, returning the graft to the back table during the PV inflow modulation can prevent graft loss. PMID:27306916

  20. Adrenal pseudotumors on CT due to dilated portosystemic veins

    SciTech Connect

    Mitty, H.M.; Cohen, B.A.; Sprayregen, S.; Schwartz, K.

    1983-10-01

    The adrenal and periadrenal venous systems are part of the portosystemic collateral pathways that may enlarge in portal hypertension. The cross-sectional image of the resulting enlarged venous channels may simulate an adrenal msss. Three examples of such computed tomographic (CT) scans are presented with selective venographic correlation. Patients with portal hypertension and suspected adrenal pathology may require enhanced or dynamic CT scans.

  1. 30 CFR 56.6401 - Shunting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shunting. 56.6401 Section 56.6401 Mineral....6401 Shunting. Except during testing— (a) Electric detonators shall be kept shunted until connected to the blasting line or wired into a blasting round; (b) Wired rounds shall be kept shunted...

  2. Outcome analysis of shunt surgery in hydrocephalus

    PubMed Central

    Ahmed, Ashraf; Sandlas, Gursev; Kothari, Paras; Sarda, Dinesh; Gupta, Abhaya; Karkera, Parag; Joshi, Prashant

    2009-01-01

    Aim: To study the clinical outcome of shunt surgeries in children suffering from hydrocephalus. Methods: A prospective study of 50 children with hydrocephalus who underwent a ventriculo-peritoneal shunt insertion over a period of two years. These patients were then followed up for shunt related complications, shunt revisions and outcome. Results: Twenty six of the 50 patients (52%) suffered from complications. The most common complications were shunt blockage (n=7) and shunt infection (n=6). These complications necessitated repeated shunt revisions. Conclusions: Infective complications of hydrocephalus are more likely to leave behind an adverse neurological outcome in the form of delayed milestones and mental retardation. PMID:20376249

  3. To shunt or not to shunt: hydrocephalus and dysraphism.

    PubMed

    Rekate, H L

    1985-01-01

    Objective criteria are available for decision making in children with ventriculomegaly and spina bifida cystica. Figure 29.7 is the evaluation algorithm used in the Hydrocephalus/Myelodysplasia Clinic at Rainbow Babies and Children's Hospital. In children without serious neurosurgical complications such as the Chiari crisis or problems with wound healing, we rely on three reasonably objective measurements for decision making. Head circumference: Measured daily while in hospital and at each visit. If the pattern of head growth crosses multiple percentile lines indicating that the child will be severely megalencephalic, a shunt will be performed. Ultrasonography: Ultrasound determinations are made in the first few days of life, prior to discharge, at 6 weeks of age, and each 6 weeks of age until 6 months. Some measurements of ventricular size (usually CT scan because of a small anterior fontanelle) should be made at age 1 year. Denver Developmental Testing (DDST): These are performed at age 6 weeks and each 6 weeks thereafter. If the child shows significant ventriculomegaly, a shunt is performed. When the results are questionable the decision is delayed and the test repeated in 6 weeks. Whether a shunt is or is not placed in an infant with ventriculomegaly and myelodysplasia, follow-up must remain compulsive. Following shunting, not only should the head circumference stabilize, but the cortical mantle should increase. Often children shunted in this situation fail to show signs of increased intracranial pressure with shunt malfunction and must be followed with serial head circumference measurements as well as ultrasounds and CT scans. If the decision is made not to shunt the child the work of Hall et al. (10) would suggest the possibility that later in life shunts may be needed to prevent scoliosis secondary to hydromyelia. More information is needed as the aggressively treated population become adults. PMID:2415285

  4. Percutaneous Placement and Management of Peritoneovenous Shunts

    PubMed Central

    Martin, Louis G.

    2012-01-01

    Peritoneovenous shunts are used in the treatment of recurrent ascites or recurrent pleural effusions. Generally speaking, the shunts allow passage of ascites or pleural effusions (by either passive or active means) back into the central venous system. The most recent development in peritoneovenous shunts, known as the Denver Shunt, is a modification of a shunt developed for the treatment of hydrocephalus. In recent years, the Denver shunt has been placed by interventional radiologists. It is used to treat both cirrhotic and malignant effusions in the peritoneal and pleural cavities. Reported complications of the shunt are shunt occlusion, infection, post-shunt coagulopathy, deep vein thrombosis, catheter breakage, and leaks. This article discusses the technical aspects related to the percutaneous placement and maintenance of the Denver Shunt. PMID:23729983

  5. Clotting Problems with the Teflon-Silastic Arteriovenous Shunt in Patients on Regular Haemodialysis

    PubMed Central

    Papadimitriou, M.; Carroll, R. N. P.; Kulatilake, A. E.

    1969-01-01

    Episodes of clotting that occurred in 22 patients on regular haemodialysis were studied over a six-month period. The venous pressure during dialysis and the radiology of the Teflon-Silastic arteriovenous shunt were found to be satisfactory guides for the management of the shunt. The failure of the shunt during the early stage was mainly due to technical reasons. Histological study of the excised vessels in removed long-term shunts showed that these had failed because of rigidity and thickening of the vessel wall due to calcium and iron deposits or chronic inflammation, or both. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11 PMID:5776208

  6. Orthopaedic complications of lumboperitoneal shunts.

    PubMed

    McIvor, J; Krajbich, J I; Hoffman, H

    1988-01-01

    Lumboperitoneal (LP) shunts performed for communicating hydrocephalus have been reported to lead to neurologic deficits in the lower limbs and spinal deformities as a result of arachnoiditis. A chart review of 375 children who underwent LP shunts between 1960 and 1981 at The Hospital For Sick Children in Toronto was undertaken. Of the 375 charts reviewed, evidence of shunt-induced neurologic deficits was seen in 63 patients. Thirty-four patients had back pain with or without sciatica, 45 patients had hamstring tightness, and 40 patients had foot deformities. Forty-nine patients had lumbar hyperlordosis, lordoscoliosis, and scoliosis. These deformities are postulated to be the result of arachnoiditis involving the conus medullaris and lower lumbar roots. PMID:3192696

  7. 49 CFR 236.838 - Wire, shunt.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Wire, shunt. 236.838 Section 236.838 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Wire, shunt. A wire forming part of a shunt circuit....

  8. 30 CFR 57.6401 - Shunting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shunting. 57.6401 Section 57.6401 Mineral...-Surface and Underground § 57.6401 Shunting. Except during testing— (a) Electric detonators shall be kept shunted until connected to the blasting line or wired into a blasting round; (b) Wired rounds shall...

  9. [Refractory ascites: a fifteen-year experience with the peritoneovenous shunt].

    PubMed

    Cattaneo, U; Enrico, S; Serra, G C; Bergoglio, D; Corno, F; Fronda, G R

    1993-09-01

    The authors consider the various causes of ascites and they also develop the concept of refractory ascites. They consider the various possibilities of medical and dietary therapy whose failure constitutes the basis for a surgical approach. In the latter case it is being considered the Peritoneo Venous Shunt (PVS) that employs different types of valves. In the light of their personal experience, matured over a period of 15 years, in which 75 valves were positioned in 64 patients and precisely: 55 valves of Le Veen, 15 Hakim and 5 Denver, it is emphasized that the best results, as for as mortality and morbidity goes, were obtained through careful attention in the preoperative stage and during surgery itself with the privileged use of a Le Veen's valve. For such motives, since in a high percentage of these patients there persists a poor prognosis a year away from the onset of refractory ascites, a PVS seems proposable anyway and even though this will not alter the pathological outcome, there's a clear improvement in the quality of life without precluding any other surgical approach. Finally, the authors outline the possibilities offered by the Transjugular Intrahepatic Portosystemic Shunt (TIPS), as a new original approach for the resolution of refractory ascites. PMID:8286483

  10. Students with Shunts: Program Considerations.

    ERIC Educational Resources Information Center

    French, Ron; And Others

    1997-01-01

    Examines how the medical condition of hydrocephalus can affect physical education students and physical education programs, and stresses the need to provide physical educators with information on students' medical conditions. Describes hydrocephalus and its treatment with ventricular peritoneal shunts, and offers suggestions on modifying…

  11. Effect of rapamycin on hepatic osteodystrophy in rats with portasystemic shunting

    PubMed Central

    van der Merwe, Schalk W; Conradie, Maria M; Bond, Robert; Olivier, Brenda J; Fritz, Elongo; Nieuwoudt, Martin; Delport, Rhena; Slavik, Tomas; Engelbrecht, Gert; Kahn, Del; Shephard, Enid G; Kotze, Maritha J; de Villiers, Nico P; Hough, Stephen

    2006-01-01

    AIM: To study if T-cell activation related to portasystemic shunting causes osteoclast-mediated bone loss through RANKL-dependent pathways. We also investigated if T-cell inhibition using rapamycin would protect against bone loss in rats. METHODS: Portasystemic shunting was performed in male Sprague-Dawley rats and rapamycin 0.1 mg/kg was administered for 15 wk by gavage. Rats received powderized chow and supplemental feeds to prevent the effects of malnutrition on bone composition. Weight gain and growth was restored after surgery in shunted animals. At termination, biochemical parameters of bone turnover and quantitative bone histology were assessed. Markers of T-cell activation, inflammatory cytokine production, and RANKL-dependent pathways were measured. In addition, the roles of IGF-1 and hypogonadism were investigated. RESULTS: Portasystemic shunting caused low turnover osteoporosis that was RANKL independent. Bone resorbing cytokine levels, including IL-1, IL-6 and TNFα, were not increased in serum and TNFα and RANKL expression were not upregulated in PBMC. Portasystemic shunting increased the circulating CD8+ T-cell population. Rapamycin decreased the circulating CD8+ T-cell population, increased CD8+ CD25+ T-regulatory cell population and improved all parameters of bone turnover. CONCLUSION: Osteoporosis caused by portasystemic shunting may be partially ameliorated by rapamycin in the rat model of hepatic osteodystrophy. PMID:16874862

  12. Shunt regulation electric power system

    NASA Technical Reports Server (NTRS)

    Wright, W. H.; Bless, J. J. (Inventor)

    1971-01-01

    A regulated electric power system having load and return bus lines is described. A plurality of solar cells interconnected in a power supplying relationship and having a power shunt tap point electrically spaced from the bus lines is provided. A power dissipator is connected to the shunt tap point and provides for a controllable dissipation of excess energy supplied by the solar cells. A dissipation driver is coupled to the power dissipator and controls its conductance and dissipation and is also connected to the solar cells in a power taping relationship to derive operating power therefrom. An error signal generator is coupled to the load bus and to a reference signal generator to provide an error output signal which is representative of the difference between the electric parameters existing at the load bus and the reference signal generator. An error amplifier is coupled to the error signal generator and the dissipation driver to provide the driver with controlling signals.

  13. Experimental Percutaneous Extrahepatic Portacaval Shunt Creation by Transjugular Approach in Swine

    SciTech Connect

    Seong, Chang Kyu; Pavcnik, Dusan Uchida, Barry T.; Anai, Hiroshi; Timmermans, Hans; Niyyati, Mahtab; Corless, Christopher L.; Correa, Luiz O.; Keller, Frederick S.; Roesch, Josef

    2005-06-15

    The purpose of the study was to evaluate the feasibility of the creation of a percutaneous extrahepatic portacaval shunt (PEPS) in swine by a transjugular approach and to find a suitable stent-graft to use in PEPS. In 12 swine, the extrahepatic portal vein (PV) was entered from the inferior vena cava (IVC) by a needle system introduced from the transjugular approach. A catheter introduced through the transhepatic approach served as a target. Five types of stent-graft consisting of homemade Z stents and a polytetrafluoethylene cover were explored for PEPS creation. Eight animals had follow-up venograms up to 6 weeks or until the shunt became severely stenotic. Gross and histologic examinations were performed after the final follow-up venography. The PV punctures and stent-graft placement were difficult, but the PEPS was established in all animals. In four animals, the stent-graft failed to adequately cover the tract, causing severe hemorrhage. Only two shunts remained patent up to 6 weeks. The other shunts exhibited severe stenosis or occlusion. At gross examination, all shunts traversed the liver parenchyma of the caudate lobe surrounding the IVC. The extravascular PEPS portion was 4 mm to 2 cm long. All shunts entered the PV close to the splenomesenteric junction and exhibited neointimal formation. Shunt stenoses were caused by neointimal hyperplasia and occlusions by a superimposed thrombus. PEPS can be created by the transjugular approach in swine, but only the PV shunt entrance is extrahepatic. None of the tested rigid stent-grafts were suitable for PEPS creation. A short flexible stent-graft with flanged ends is suggested for further exploration.

  14. Transjugular Intrahepatic Portosystemic Shunt (TIPS) in the Treatment of Venous Symptomatic Chronic Portal Thrombosis in Non-cirrhotic Patients

    SciTech Connect

    Bilbao, Jose I. Elorz, Mariana; Vivas, Isabel; Martinez-Cuesta, Antonio; Bastarrika, Gorka; Benito, Alberto

    2004-09-15

    Purpose: To present a series of cases of non-cirrhotic patients with symptomatic massive portal thrombosis treated by percutaneous techniques. All patients underwent a TIPS procedure in order to maintain the patency of the portal vein by facilitating the outflow. Methods: A total of six patients were treated for thrombosis of the main portal vein (6/6); the main right and left branches (3/6) and the splenic vein (5/6) and superior mesenteric vein (6/6). Two patients had a pancreatic malignancy; one patient with an orthotopic liver transplant had been surgically treated for a pancreatic carcinoma. Two patients had idiopathic thrombocytosis, and in the remaining patient no cause for the portal thrombosis was identified. During the initial procedure in each patient one or more approaches were tried: transhepatic (5/6), transileocolic (1/6), trans-splenic (1/6) or transjugular (1/6). In all cases the procedure was completed with a TIPS with either ultrasound guidance (3/6), 'gun-shot' technique (2/6) or fluoroscopic guidance (1/6).Results: No complications were observed during the procedures. One patient had a repeat episode of variceal bleeding at 30 months, one patient remained asymptomatic and was lost to follow-up at 24 months, two patients were successfully treated surgically (cephalic duodenopancreatectomy) and are alive at 4 and 36 months. One patient remains asymptomatic (without new episodes of abdominal pain) at 16 months of follow-up. One patient died because of tumor progression at 10 months. Conclusion: Percutaneous techniques for portal recanalization are an interesting alternative even in non-acute thrombosis. Once flow has been restored in the portal vein TIPS may be necessary to obtain an adequate outflow, hence facilitating and maintaining the portal flow.

  15. Custom-made covered transjugular intrahepatic portosystemic shunt (TIPS) in an infant with trisomy 22 and biliary atresia.

    PubMed

    Chlapoutaki, Chrysanthi Emmanouil; Franchi-Abella, Stephanie; Habes, Dalila; Pariente, Daniele

    2009-07-01

    We report an 8-month-old girl with portal hypertension secondary to biliary atresia. The decision to treat with TIPS was made at the age of 8 months due to recurrent variceal bleeding. The procedure was carried out with a 6-mm bare stent due to her small size. Radiological follow-up with Doppler US showed gradual stenosis and finally occlusion of the stent 80 days after implantation. Revision was performed with placement of an additional 6-mm expanded polytetrafluoroethylene (e-PTFE) stent-graft that had remained patent for 9 months, proving that in small children with a portal vein diameter less than 8 mm, the combination of a bare stent and stent-graft can provide excellent results. PMID:19300990

  16. Arterioportal shunts on dynamic computed tomography

    SciTech Connect

    Nakayama, T.; Hiyama, Y.; Ohnishi, K.; Tsuchiya, S.; Kohno, K.; Nakajima, Y.; Okuda, K.

    1983-05-01

    Thirty-two patients, 20 with hepatocelluar carcinoma and 12 with liver cirrhosis, were examined by dynamic computed tomography (CT) using intravenous bolus injection of contrast medium and by celiac angiography. Dynamic CT disclosed arterioportal shunting in four cases of hepatocellular carcinoma and in one of cirrhosis. In three of the former, the arterioportal shunt was adjacent to a mass lesion on CT, suggesting tumor invasion into the portal branch. In one with hepatocellular carcinoma, the shunt was remote from the mass. In the case with cirrhosis, there was no mass. In these last two cases, the shunt might have been caused by prior percutaneous needle puncture. In another case of hepatocellular carcinoma, celiac angiography but not CT demonstrated an arterioportal shunt. Thus, dynamic CT was diagnostic in five of six cases of arteriographically demonstrated arterioportal shunts.

  17. 21 CFR 886.3920 - Aqueous shunt.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Aqueous shunt. 886.3920 Section 886.3920 Food and... OPHTHALMIC DEVICES Prosthetic Devices § 886.3920 Aqueous shunt. (a) Identification. An aqueous shunt is an... Review Guidance of 2/12/90 (K90-1),” and (3) “Aqueous Shunts—510(k) Submissions.”...

  18. Radiological Insertion and Management of Peritoneovenous Shunt

    SciTech Connect

    Bratby, M. J.; Hussain, F. F. Lopez, A. J.

    2007-06-15

    The purpose of the study was to report our experience of the management of complications following the insertion of a peritoneovenous shunt for intractable malignant ascites. From June 1999 to January 2006, 26 patients underwent insertion of a peritoneovenous shunt for ascites by interventional radiologists. We have used ultrasound and shuntography to assist in the diagnosis of the cause of shunt blockage. Successful techniques for the restoration of the shunt function include port- pumping, stripping of any fibrin sheath, and revision of either the venous or peritoneal catheter. The procedure was initially successful in all patients with continued patency until death in 17. A further four patients are still alive with a functioning shunt. There was one rapid postprocedure death resulting from pulmonary edema. Two patients developed pneumothorax, managed successfully with either a chest drain or aspiration. Shunt dysfunction occurred eight times in seven patients. There were five successful revisions in four patients. Overall, shunt patency has been maintained in 80.1% of patients. Shunt dysfunction is seen in a significant number of patients, but successful revision of the shunt can be achieved in the majority.

  19. Headaches in patients with shunts.

    PubMed

    Rekate, Harold L; Kranz, Dory

    2009-03-01

    Headache is one of the most common afflictions suffered by humans. Headache in patients with a shunt triggers a series of events that includes utilization of expensive technologies and often potentially dangerous surgical intervention. The purpose of this study was to determine the incidence of headaches in patients with shunts and, hopefully, the relationship of those headache disorders to the treatment of hydrocephalus. The Hydrocephalus Association maintains a self-reporting database recorded from individuals treated for hydrocephalus and their families. This database was mined to determine the incidence of severe headaches requiring treatment and interfering with normal life in patients who have been treated for hydrocephalus. There were 1,242 responders between the ages of 19 months and 45 years of age. Of these, 1,233 answered the question, "Do you or your family member suffer from (does your child complain of) frequent or chronic headaches?" This subset forms the basis of this study. Three groups were defined by age: children (19 months-12 years), adolescents (13 years-19 years), and young adults (20 years-45 years). Most respondents were initially treated during infancy (before 18 months of age); 84% of children and 69% of both adolescents and young adults were treated very early in life. Severe headaches became a more frequent problem as the age of the population treated for hydrocephalus increased. In terms of frequency and severity of headaches, direct comparisons with epidemiologic studies of normal populations are difficult because of the limitations of data available in the database. However, it is likely that this population has a higher incidence of severe headaches than normal populations. The cost of management of headaches in this population is very high, and the patients are at risk throughout life. Early treatment decisions have a significant effect on later quality of life. Strategies that lead to normalization of cerebrospinal fluid dynamics

  20. [Temporary distance shunting of the anastomosis with a probe shunt].

    PubMed

    Abdulzhalilov, M K; Gaĭbatov, S P

    2003-01-01

    The authors present results of using temporary shunting of intestinal anastomosis in combination with selective lavage of the suture line with a curative antiseptic mixture in experiment in 12 dogs and in clinic in 36 patients with a probe of the authors' original construction. The probe consists of a polychlorvenyl tube with the inner diameter 0.8-1.0 cm, having two inflatable rubber cuffs mounted on the distal end at a distance of 15 cm from each other. After inflation of the cuffs a closed isolated cavity is formed in the zone of intestinal sutures, into which the distal end of the tube is opened for the decompression and selective intraluminal lavage of the anastomosis. The using of the temporary shunting of intestinal anastomosis in combination with selective intraluminal lavage with a mixture of broad-spectrum antibiotics and antioxidant 1.5% Reamberin accelerates the process of the intestinal suture healing, results in favorable course of the postoperative period, prevents complications. PMID:14768105

  1. The Budd-Chiari syndrome. Treatment by mesenteric-systemic venous shunts.

    PubMed Central

    Cameron, J L; Herlong, H F; Sanfey, H; Boitnott, J; Kaufman, S L; Gott, V L; Maddrey, W C

    1983-01-01

    Twelve patients with the Budd-Chiari syndrome have been managed surgically. Ten of the patients were female, two were male, with a mean age of 40 years. Three of the patients had polycythemia vera, two had pre-existing cirrhosis, one had ingested estrogens, one had an occult tumor, and in four there were no associated factors. Ten patients presented with ascites and two with bleeding esophageal varices. The diagnosis was confirmed in all 12 patients by liver biopsy and hepatic vein catheterization. Inferior vena cavography revealed the abdominal vena cava to be thrombosed in six patients. The superior mesenteric vein was used to decompress the congested liver in all 12 patients. In five patients, a mesocaval shunt (MCS) was performed and in seven patients, a mesoatrial shunt (MAS) was carried out. There were four hospital deaths (two MCS, two MAS). One late death (MAS) occurred from liver failure following shunt thrombosis. Two additional patients (one MCS, one MAS) re-developed ascites immediately following surgery and angiography revealed a thrombosed shunt. Ascites has been controlled with a LeVeen shunt in these two patients, but liver biopsies showed progression to cirrhosis. The remaining five patients (three MAS, two MCS) did well, and angiography revealed patent shunts. Two of these patients, however, re-developed ascites at 4 and 10 months following MAS and required a second MAS. Follow-up ranges from 6 to 68 months. In three of the patients (two MCS, one MAS) with patent shunts, liver biopsy shows a remarkable return toward normal liver architecture and histology. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. PMID:6615056

  2. 21 CFR 874.3820 - Endolymphatic shunt.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Endolymphatic shunt. 874.3820 Section 874.3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt....

  3. 21 CFR 874.3820 - Endolymphatic shunt.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Endolymphatic shunt. 874.3820 Section 874.3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt....

  4. 21 CFR 874.3820 - Endolymphatic shunt.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Endolymphatic shunt. 874.3820 Section 874.3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt....

  5. 21 CFR 874.3820 - Endolymphatic shunt.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Endolymphatic shunt. 874.3820 Section 874.3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt....

  6. 21 CFR 874.3820 - Endolymphatic shunt.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Endolymphatic shunt. 874.3820 Section 874.3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3820 Endolymphatic shunt....

  7. Does the Warren Shunt Correct Hypersplenism?

    PubMed Central

    Mavor, Andrew I. D.; Giles, Geoffrey R.

    1990-01-01

    It has been suggested that patients with bleeding varices and hypersplenism will show significant improvements in leucocyte and platelet counts following distal splenorenal (Warren) shunt surgery. Whilst this may be true in the short term, this report shows that in the long term hypersplenism is not relieved, whereas the lienorenal shunt is associated with a return of normal haematological values. PMID:2282329

  8. 49 CFR 236.802 - Shunt.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Shunt. 236.802 Section 236.802 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.802 Shunt. A...

  9. 49 CFR 234.229 - Shunting sensitivity.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail...

  10. 49 CFR 236.56 - Shunting sensitivity.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home...

  11. 49 CFR 236.56 - Shunting sensitivity.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home...

  12. 49 CFR 236.56 - Shunting sensitivity.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home...

  13. 49 CFR 234.229 - Shunting sensitivity.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail...

  14. 49 CFR 236.56 - Shunting sensitivity.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home...

  15. 49 CFR 236.56 - Shunting sensitivity.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Shunting sensitivity. 236.56 Section 236.56 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...: All Systems Track Circuits § 236.56 Shunting sensitivity. Each track circuit controlling home...

  16. [Systemic-pulmonary artery shunt using Golaski graft: trial for measurement of the shunt flow].

    PubMed

    Togo, T; Ito, T; Hata, M; Murata, S; Osaka, K; Komatsu, T; Tabayashi, K; Haneda, K; Mohri, T

    1995-03-01

    For the systemic-pulmonary artery shunt operation, the modified Blalock-Taussig shunt was the first choice for procedure in our institution. Since 1990, Golaski knitted Dacron graft (4 or 5 mm in diameter) was used for the prosthesis. Ex-vivo flow calibration of the electromagnetic flow meter (Nihon Koden, MFV-3100) to Golaski graft showed good correlation between the real flow and value measured by the electromagnetic flow meter. Shunt flow was measured in the consecutive clinical fifteen cases. The shunt flow per body surface area of the patient who required additional shunt operation was 721 ml/min/m2 and one patient in whom the congestive heart failure developed after the shunt operation, had the shunt flow of 3,022 ml/min/m2. The adequate shunt flow in these cases was ranged from 745 to 2,820 ml/min/m2 (mean +/- 1 SD, 1,490 +/- 587.8). Therefore we performed the systemic-pulmonary artery shunt operation using Golaski graft to get the shunt flow of 1,000 ml/min/m2 (approximately a third of cardiac index) for the guide of good results. PMID:7897896

  17. The Preventable Shunt Revision Rate: a potential quality metric for pediatric shunt surgery.

    PubMed

    Venable, Garrett T; Rossi, Nicholas B; Morgan Jones, G; Khan, Nickalus R; Smalley, Zachary S; Roberts, Mallory L; Klimo, Paul

    2016-07-01

    OBJECTIVE Shunt surgery consumes a large amount of pediatric neurosurgical health care resources. Although many studies have sought to identify risk factors for shunt failure, there is no consensus within the literature on variables that are predictive or protective. In this era of "quality outcome measures," some authors have proposed various metrics to assess quality outcomes for shunt surgery. In this paper, the Preventable Shunt Revision Rate (PSRR) is proposed as a novel quality metric. METHODS An institutional shunt database was queried to identify all shunt surgeries performed from January 1, 2010, to December 31, 2014, at Le Bonheur Children's Hospital. Patients' records were reviewed for 90 days following each "index" shunt surgery to identify those patients who required a return to the operating room. Clinical, demographic, and radiological factors were reviewed for each index operation, and each failure was analyzed for potentially preventable causes. RESULTS During the study period, there were 927 de novo or revision shunt operations in 525 patients. A return to the operating room occurred 202 times within 90 days of shunt surgery in 927 index surgeries (21.8%). In 67 cases (33% of failures), the revision surgery was due to potentially preventable causes, defined as inaccurate proximal or distal catheter placement, infection, or inadequately secured or assembled shunt apparatus. Comparing cases in which failure was due to preventable causes and those in which it was due to nonpreventable causes showed that in cases in which failure was due to preventable causes, the patients were significantly younger (median 3.1 vs 6.7 years, p = 0.01) and the failure was more likely to occur within 30 days of the index surgery (80.6% vs 64.4% of cases, p = 0.02). The most common causes of preventable shunt failure were inaccurate proximal catheter placement (33 [49.3%] of 67 cases) and infection (28 [41.8%] of 67 cases). No variables were found to be predictive of

  18. 21 CFR 882.4545 - Shunt system implantation instrument.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... implantation instrument. (a) Identification. A shunt system implantation instrument is an instrument used in the implantation of cerebrospinal fluid shunts, and includes tunneling instruments for passing shunt... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Shunt system implantation instrument....

  19. Pneumocephalus following ventriculoperitoneal shunt. Case report.

    PubMed

    Pitts, L H; Wilson, C B; Dedo, H H; Weyand, R

    1975-11-01

    The authors describe a case of massive pneumocephalus following ventriculoperitoneal shunting for hydrocephalus. After multiple diagnostic and surgical procedures, congenital defects in the tegmen tympani of both temporal bones were identified as the sources for entry of air. A functioning shunt intermittently established negative intracranial pressure and allowed ingress of air through these abnormalities; when the shunt was occluded, air did not enter the skull, and there was no cerebrospinal fluid leakage. Repair of these middle ear defects prevented further recurrence of pneumocephalus. PMID:1181396

  20. Ventriculoperitoneal Shunt Peritoneal Catheter Knot Formation

    PubMed Central

    Ul-Haq, Anwar; Al-Otaibi, Faisal; Alshanafey, Saud; Sabbagh, Mohamed Diya; Al Shail, Essam

    2013-01-01

    The ventriculoperitoneal (VP) shunt is a common procedure in pediatric neurosurgery that carries a risk of complications at cranial and abdominal sites. We report on the case of a child with shunt infection and malfunction. The peritoneal catheter was tethered within the abdominal cavity, precluding its removal. Subsequently, laparoscopic exploration identified a knot at the distal end of the peritoneal catheter around the omentum. A new VP shunt was inserted after the infection was healed. This type of complication occurs rarely, so there are a limited number of case reports in the literature. This report is complemented by a literature review. PMID:24109528

  1. Reversible occlusion shunt for intraventricular chemotherapy in shunt-dependent brain tumor patients.

    PubMed

    Czech, T; Reinprecht, A; Dietrich, W; Hainfellner, J A; Slavc, I

    1997-01-01

    Intraventricular chemotherapy is increasingly used in the treatment of pediatric brain tumors with leptomeningeal seeding. However, some patients are shunt dependent after surgery, probably due to adhesions in the area of surgery. To avoid drug diversion in these patients we connected the reservoir to a reversible occlusion device. Over a 2-year period a shunt value with an on-off device was inserted into the shunt assembly of eight children with various brain tumors with a poor prognosis undergoing intraventricular chemotherapy. All eight patients had tumor cells in the ventricular cerebrospinal fluid (CSF) and/or metastases by magnetic resonance imaging. The number of intraventricular drug applications ranged from 10 to 51. No shunt malfunctions or shunt-related infections occurred. The temporary closure of the shunt after drug delivery was well tolerated. In all six children with tumor cells in the ventricular CSF a negative cytology was achieved over a 3- to 8-week period. PMID:9211542

  2. Scintisplenoportography in assessing patency of distal splenorenal shunts

    SciTech Connect

    Teres, J.; Herranz, R.; Visa, J.; Lomena, F.; Pera, C.; Rodes, J.

    1983-06-01

    Scintisplenoportography was performed on 33 occasions in 28 cirrhotic patients who had bled from esophagogastric varices. In 17 cases scintisplenoportography was carried out after a retroperitoneal distal splenorenal shunt procedure and in the remaining 16 instances in patients without any surgical shunt. In four patients scintisplenoportography was performed before and after a surgical shunt procedure, and in one case, before and after the shunt thrombosed. Gammagraphic patterns and spleen-heart times helped determine which patients did not have a surgical shunt, which had a patent shunt, and which patients had a thrombosed shunt. A patent shunt pattern and a thrombosed shunt pattern have been defined. It is concluded that scintisplenoportography is a useful, reproducible, and safe method to assess the patency of distal splenorenal shunts.

  3. Arne Torkildsen and the ventriculocisternal shunt: the first clinically successful shunt for hydrocephalus.

    PubMed

    Eide, Per Kristian; Lundar, Tryggve

    2016-05-01

    Arne Torkildsen was a pioneering Norwegian neurosurgeon who introduced the ventriculocisternal shunt, the first clinically successful shunt for CSF diversion in hydrocephalus. The procedure, usually referred to as ventriculocisternostomy (VCS), Torkildsen's operation, orTorkildsen's shunt, became internationally recognized as an efficient operation for the treatment of noncommunicating hydrocephalus. The operation gained widespread use in the 1940s and 1950s before the introduction of extracranial shunts. In this paper, the authors look more closely at Torkildsen's development of the VCS and examine how this surgical approach differed from other procedures for treating hydrocephalus before World War II. Long-term results of the VCS are presented. PMID:26339852

  4. Severe respiratory failure following ventriculopleural shunt

    PubMed Central

    Alam, Shahzad; Manjunath, Nagaraju M.

    2015-01-01

    Cerebrospinal fluid (CSF) diversion procedure has been used for long to treat hydrocephalus in children. The principle of shunting is to establish a communication between the CSF and a drainage cavity (peritoneum, right atrium, and pleura). Ventriculoperitoneal shunt is used most commonly, followed secondly by ventriculopleural shunt (VPLS). Hydrothorax due to excessive CSF accumulation is a rare complication following both the type of shunts and is more frequently seen with VPLS. We report a case of a 6-year-old female child presenting with massive CSF hydrothorax with respiratory failure following VPLS. The aim of the article is to highlight early recognition of this rare and life-threatening condition, which could easily be missed if proper history is not available. PMID:26730125

  5. Severe respiratory failure following ventriculopleural shunt.

    PubMed

    Alam, Shahzad; Manjunath, Nagaraju M

    2015-11-01

    Cerebrospinal fluid (CSF) diversion procedure has been used for long to treat hydrocephalus in children. The principle of shunting is to establish a communication between the CSF and a drainage cavity (peritoneum, right atrium, and pleura). Ventriculoperitoneal shunt is used most commonly, followed secondly by ventriculopleural shunt (VPLS). Hydrothorax due to excessive CSF accumulation is a rare complication following both the type of shunts and is more frequently seen with VPLS. We report a case of a 6-year-old female child presenting with massive CSF hydrothorax with respiratory failure following VPLS. The aim of the article is to highlight early recognition of this rare and life-threatening condition, which could easily be missed if proper history is not available. PMID:26730125

  6. Syringosubarachnoid shunting using a myringotomy tube

    PubMed Central

    Leschke, Jack M.; Mumert, Michael L.; Kurpad, Shekar N.

    2016-01-01

    Background: Syringomyelia results from obstruction of cerebrospinal fluid (CSF) flow due to a multitude of causes. Often symptoms of pain, weakness, and sensory disturbance are progressive and require surgical treatment. We present here a rare technique for syringosubarachnoid shunting. Case Description: We present the case of a 38-year-old male who suffered a traumatic cervical spinal cord injury due to a motor vehicle accident. With progressive pain and motor decline, a magnetic resonance imaging was obtained and showed a new syrinx extending cervical multiple segments. A unique surgical procedure using a myringotomy tube to shunt CSF into the subarachnoid space was employed in this case. The patient's examination stabilized postoperatively, and at 2 months and 6 months follow-up visits, his strength and sensation continued to improve. Conclusion: We used a myringotomy tube for syringosubarachnoid shunting for the surgical management of a posttraumatic syrinx with good results. This technique minimizes suturing and may minimize shunt-related complications. PMID:26862456

  7. Cell shunt resistance and photovoltaic module performance

    SciTech Connect

    McMahon, T.J.; Basso, T.S.; Rummel, S.R.

    1996-05-01

    Shunt resistance of cells in photovoltaic modules can affect module power output and could indicate flawed manufacturing processes and reliability problems. The authors describe a two-terminal diagnostic method to directly measure the shunt resistance of individual cells in a series-connected module non-intrusively, without deencapsulation. Peak power efficiency vs. light intensity was measured on a 12-cell, series-connected, single crystalline module having relatively high cell shunt resistances. The module was remeasured with 0.5-, 1-, and 2-ohm resistors attached across each cell to simulate shunt resistances of several emerging technologies. Peak power efficiencies decreased dramatically at lower light levels. Using the PSpice circuit simulator, the authors verified that cell shunt and series resistances can indeed be responsible for the observed peak power efficiency vs. intensity behavior. The authors discuss the effect of basic cell diode parameters, i.e., shunt resistance, series resistance, and recombination losses, on PV module performance as a function of light intensity.

  8. Vasopressin and splanchnic shunting. A quantitative comparison.

    PubMed Central

    Chandler, J G

    1982-01-01

    To analyze the relationship between the splanchnic and systemic effects of vasopressin and to measure its efficacy in lowering portal pressure relative to what can be accomplished by zero gradient shunting, intraoperative measurements of cardiac output and relevant pressures were made in 30 patients undergoing selective or total shunts. Vasopressin caused a significant increase in systemic vascular resistance and pulmonary capillary wedge pressure, but an insignificant overall reduction in cardiac index (CI). However, in ten patients the decrease in CI exceeded 20%, suggesting a subpopulation of especially susceptible individuals. High initial CI, age, pre-existent heart disease, and severity of cirrhosis did not predict greater vulnerability. Adding an infusion of nitroprusside regularly reverted CI to control levels, regardless of the extent of cardiac output depression. Vasopressin was 38% as effective as a subsequent shunt in reducing splanchnic venous pressure. The portal hypotensive action bore no relationship to CI, but the pressure decrease caused by vasopressin was predictive of the reduction that could be achieved by shunting. The effects of the two types of shunts on systemic hemodynamics were minor and remarkably similar. PMID:7073352

  9. Pleuroperitoneal shunt for recurrent malignant pleural effusions.

    PubMed Central

    Tsang, V; Fernando, H C; Goldstraw, P

    1990-01-01

    The therapeutic options available for the management of malignant pleural effusions associated with a restricting malignant cortex remain unsatisfactory. The efficacy of pleuroperitoneal shunts was evaluated in 16 patients with recurrent malignant effusions. There were no operative deaths; one patient died on the third postoperative day as a result of lymphangitis carcinomatosa. The median hospital stay was five (range 3-21) days. Palliation was obtained in all but one of the other 15 patients. There was no appreciable reaccumulation of pleural fluid as judged by radiography. Two patients developed occlusion of the shunt. In one case this was due to blood clots in the pleural catheter and necessitated insertion of a new shunt. The other shunt was removed because of obstructing infected fibrin debris, and a rib resection was performed. There were eight deaths related to the underlying malignancy after a mean interval of 7.3 (range 1.5-23) months. The other six patients are still alive, with a mean survival of 11.0 (range 5-20) months, and have achieved good symptomatic relief. The insertion of a pleuroperitoneal shunt can offer effective palliation for patients with recurrent malignant pleural effusions. Images PMID:1696401

  10. Clinico-Histologic Conferences: Histology and Disease

    ERIC Educational Resources Information Center

    Shaw, Phyllis A.; Friedman, Erica S.

    2012-01-01

    Providing a context for learning information and requiring learners to teach specific content has been demonstrated to enhance knowledge retention. To enhance students' appreciation of the role of science and specifically histology in clinical reasoning, disease diagnosis, and treatment, a new teaching format was created to provide clinical…

  11. Radionuclide demonstration of intrapulmonary shunting in cirrhosis

    SciTech Connect

    Bank, E.R.; Thrall, J.H.; Dantzker, D.R.

    1983-05-01

    The association of hepatic cirrhosis and severe arterial hypoxemia has been well described. Although alterations in ventilatory function may partially account for the hypoxemia, the principal mechanism is thought to be a microangiopathic change in the pulmonary vasculature resulting in intrapulmonary arteriovenous shunting with resultant systemic desaturation. Whole-body radionuclide scans with technetium-99m macroaggregated albumin labeling have been diagnostic of right-to-left shunting by their demonstration of tracer accumulation within the extrapulmonary circulation. A case of severe pulmonary arteriovenous shunting in an alcoholic patient in whom hepatic disease had not been of apparent clinical significance before radionuclide scanning is reported. He did not have cuntaeous angiomata as have all other patients with alcoholic cirrhosis and hypoxemia.

  12. Radionuclide demonstration of intrapulmonary shunting in cirrhosis

    SciTech Connect

    Bank, E.R.; Thrall, J.H.; Dantzker, D.R.

    1983-05-01

    The association of hepatic cirrhosis and severe arterial hypoxemia has been well described. Although alterations in ventilatory function may partially account for the hypoxemia, the principal mechanism is thought to be a microangiopathic change in the pulmonary arteriovenous shunting with resultant systemic desaturation. Whole-body radionuclide scans with technetium-99m macroaggrregated albumin (/sup 99m/Tc MAA) labeling have been diagnostic of right-to-left shunting by their demonstration of tracer accumulation within the extrapulmonary circulation. A case of severe pulmonary arteriovenous shunting in an alcoholic patient in whom hepatic disease had not been of apparent clinical significance before radionuclide scanning is reported. He did not have cutaneous angiomata as have all other patients with alcoholic cirrhosis and hypoxemia.

  13. Ventricular shunt infections: Immunopathogenesis and clinical management

    PubMed Central

    Gutierrez-Murgas, Yenis; Snowden, Jessica N.

    2014-01-01

    Ventricular shunts are the most common neurosurgical procedure performed in the United States. This hydrocephalus treatment is often complicated by infection of the device with biofilm-forming bacteria. In this review, we discuss the pathogenesis of shunt infection, as well as the implications of the biofilm formation on treatment and prevention of these infections. Many questions remain, including the contribution of glia and the impact of inflammation on developmental outcomes following infection. Immune responses within the CNS must be carefully regulated to contain infection while minimizing bystander damage; further study is needed to design optimal treatment strategies for these patients. PMID:25156073

  14. Collagen plug occlusion of Molteno tube shunts.

    PubMed

    Stewart, W; Feldman, R M; Gross, R L

    1993-01-01

    We report five patients in whom collagen lacrimal plugs were used to temporarily occlude the lumen of Molteno shunts to prevent early postoperative hypotony. Only one eye, with a double plate, developed hypotony and a flat anterior chamber that required reformation. However, in three patients, the collagen plugs did not dissolve and had to be removed surgically to lower the intraocular pressure. Although the semipermeability of collagen is desirable, its unpredictable degradation renders it unsuitable for temporary occlusion of tube shunts. Other biodegradable materials may be more appropriate for this purpose. PMID:8446334

  15. 49 CFR 236.57 - Shunt and fouling wires.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Shunt and fouling wires. 236.57 Section 236.57...: All Systems Track Circuits § 236.57 Shunt and fouling wires. (a) Except as provided in paragraph (b) of this section, shunt wires and fouling wires hereafter installed or replaced shall consist of...

  16. 21 CFR 882.4545 - Shunt system implantation instrument.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Shunt system implantation instrument. 882.4545... (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4545 Shunt system implantation instrument. (a) Identification. A shunt system implantation instrument is an instrument used...

  17. 21 CFR 876.5955 - Peritoneo-venous shunt.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Peritoneo-venous shunt. 876.5955 Section 876.5955...) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5955 Peritoneo-venous shunt. (a) Identification. A peritoneo-venous shunt is an implanted device that consists of a catheter and a...

  18. 49 CFR 236.104 - Shunt fouling circuit.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Shunt fouling circuit. 236.104 Section 236.104 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...: All Systems Inspections and Tests; All Systems § 236.104 Shunt fouling circuit. Shunt fouling...

  19. 49 CFR 236.725 - Circuit, switch shunting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch...

  20. 49 CFR 234.229 - Shunting sensitivity.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... sensitivity. Each highway-rail grade crossing train detection circuit shall detect the application of a...

  1. 49 CFR 234.229 - Shunting sensitivity.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... sensitivity. Each highway-rail grade crossing train detection circuit shall detect the application of a...

  2. 49 CFR 234.229 - Shunting sensitivity.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... sensitivity. Each highway-rail grade crossing train detection circuit shall detect the application of a...

  3. Muzzle shunt augmentation of conventional railguns

    SciTech Connect

    Parker, J.V.

    1990-01-01

    Augmentation is a well-known technique for reducing the armature current and hence the armature power dissipation in a plasma armature railgun. In spite of the advantages, no large augmented railguns have been built, primarily due to the mechanical and electrical complexity introduce by the extra conductors required. It is possible to achieve some of the benefits of augmentation in conventional railgun by diverting a fraction {phi} of the input current through a shunt path at the muzzle of the railgun. In particular, the relation between force and armature current is the same as that obtained in an n-turn, series connected augmented railgun with n = 1/(1-{phi}). The price of this simplification is a reduction in electrical efficiency and some additional complexity in the external electrical system. Additions to the electrical system are required to establish the shunt current and to control its magnitude during projectile acceleration. The relationship between muzzle shunt augmentation and conventional series augmentation is developed and various techniques is developed and various techniques for establishing and controlling the shunt current are illustrated with a practical example. 5 refs., 8 figs., 2 tabs.

  4. Fabrication of capacitively-shunted superconducting qubits

    NASA Astrophysics Data System (ADS)

    Yoder, Jonilyn L.; Gudmundsen, Theodore J.; Bolkhovsky, Vladimir; Welander, Paul B.; Gustavsson, Simon; Hover, David; Kerman, Andrew J.; Sears, Adam P.; Oliver, William D.

    2014-03-01

    Improvements in superconducting qubit coherence times and reproducibility have been demonstrated using capacitive shunting. In this study, we present methods for the preparation of both capacitively-shunted charge qubits (transmons) and capacitively-shunted flux qubits. Hybrid fabrication techniques were employed to combine high-quality-factor aluminum capacitive shunts with shadow-evaporated Josephson junctions, and the Josephson junctions were prepared using suspended-bridge germanium masks. We also will describe process testing results that were acquired to assess wafer-to-wafer reproducibility of our fabrication protocols. This research was funded in part by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA); and by the Assistant Secretary of Defense for Research and Engineering under Air Force Contract number FA8721-05-C-0002. All statements of fact, opinion or conclusions contained herein are those of the authors and should not be construed as representing the official views or policies of IARPA, the ODNI, or the U.S. Government.

  5. Platypnea-Orthodeoxia Syndrome: To Shunt or Not to Shunt, That is the Question

    PubMed Central

    Kiefer, Todd L.; Velazquez, Eric J.

    2016-01-01

    Platypnea-orthodeoxia syndrome is a rare disease defined by dyspnea and deoxygenation, induced by an upright position, and relieved by recumbency. Causes include shunting through a patent foramen ovale and pulmonary arteriovenous malformations. A 79-year-old woman experienced 2 syncopal episodes at rest and presented at another hospital. In the emergency department, she was hypoxic, needing 6 L/min of oxygen. Her chest radiograph showed nothing unusual. Transthoracic echocardiograms with saline microcavitation evaluation were mildly positive early after agitated-saline administration, suggesting intracardiac shunting. She was then transferred to our center. Right-sided heart catheterization revealed no oximetric evidence of intracardiac shunting while the patient was supine and had a low right atrial pressure. However, her oxygen saturation dropped to 78% when she sat up. Repeat transthoracic echocardiography while sitting revealed a dramatically positive early saline microcavitation-uptake into the left side of the heart. Transesophageal echocardiograms showed a patent foramen ovale, with right-to-left shunting highly dependent upon body position. The patient underwent successful percutaneous patent foramen ovale closure, and her oxygen supplementation was suspended. In patients with unexplained or transient hypoxemia in which a cardiac cause is suspected, it is important to evaluate shunting in both the recumbent and upright positions. In this syndrome, elevated right atrial pressure is not necessary for significant right-to-left shunting. Percutaneous closure, if feasible, is first-line therapy in these patients. PMID:27303248

  6. Platypnea-Orthodeoxia Syndrome: To Shunt or Not to Shunt, That is the Question.

    PubMed

    Klein, Michael R; Kiefer, Todd L; Velazquez, Eric J

    2016-06-01

    Platypnea-orthodeoxia syndrome is a rare disease defined by dyspnea and deoxygenation, induced by an upright position, and relieved by recumbency. Causes include shunting through a patent foramen ovale and pulmonary arteriovenous malformations. A 79-year-old woman experienced 2 syncopal episodes at rest and presented at another hospital. In the emergency department, she was hypoxic, needing 6 L/min of oxygen. Her chest radiograph showed nothing unusual. Transthoracic echocardiograms with saline microcavitation evaluation were mildly positive early after agitated-saline administration, suggesting intracardiac shunting. She was then transferred to our center. Right-sided heart catheterization revealed no oximetric evidence of intracardiac shunting while the patient was supine and had a low right atrial pressure. However, her oxygen saturation dropped to 78% when she sat up. Repeat transthoracic echocardiography while sitting revealed a dramatically positive early saline microcavitation-uptake into the left side of the heart. Transesophageal echocardiograms showed a patent foramen ovale, with right-to-left shunting highly dependent upon body position. The patient underwent successful percutaneous patent foramen ovale closure, and her oxygen supplementation was suspended. In patients with unexplained or transient hypoxemia in which a cardiac cause is suspected, it is important to evaluate shunting in both the recumbent and upright positions. In this syndrome, elevated right atrial pressure is not necessary for significant right-to-left shunting. Percutaneous closure, if feasible, is first-line therapy in these patients. PMID:27303248

  7. Episodic ventriculomegaly due to hypernatremia mimicking shunt malfunction: case report.

    PubMed

    Jernigan, Sarah C; Stone, Scellig S D; Aronson, Joshua P; Putman, Melissa; Proctor, Mark R

    2015-10-01

    Patients with shunted hydrocephalus presenting with altered mental status and ventriculomegaly are generally considered to be in shunt failure requiring surgical treatment. The authors describe a case of shunted hydrocephalus secondary to a disseminated neuroectodermal tumor in a pediatric patient in whom rapid fluctuations in sodium levels due to diabetes insipidus repeatedly led to significant changes in ventricle size, with invasively confirmed normal shunt function and low intracranial pressure. This clinical picture exactly mimics shunt malfunction, requires urgent nonsurgical therapy, and underscores the importance of considering serum osmolar abnormalities in the differential diagnosis for ventriculomegaly. PMID:26186358

  8. Histologic diagnosis of sodomy.

    PubMed

    Paparo, G P; Siegel, H

    1979-10-01

    A case of homicidal strangulation with sodomy is presented. Without the use of a simple routine histologic technique, the diagnosis of sodomy could not have been unequivocally substantiated. PMID:541642

  9. EVS vs TIPS shunt for gastric variceal bleeding in patients with cirrhosis: A meta-analysis

    PubMed Central

    Bai, Ming; Qi, Xing-Shun; Yang, Zhi-Ping; Wu, Kai-Chun; Fan, Dai-Ming; Han, Guo-Hong

    2014-01-01

    AIM: To evaluate the clinical effects of transjugular intrahepatic portosystemic shunt (TIPS) vs endoscopic variceal sclerotherapy (EVS) in the management of gastric variceal (GV) bleeding in terms of variceal rebleeding, hepatic encephalopathy (HE), and survival by meta-analysis. METHODS: Medline, Embase, and CNKI were searched. Studies compared TIPS with EVS in treating GV bleeding were identified and included according to our predefined inclusion criteria. Data were extracted independently by two of our authors. Studies with prospective randomized design were considered to be of high quality. Hazard ratios (HRs) or odd ratios (ORs) were calculated using a fixed-effects model when there was no inter-trial heterogeneity. Oppositely, a random-effects model was employed. RESULTS: Three studies with 220 patients who had at least one episode of GV bleeding were included in the present meta-analysis. The proportions of patients with viral cirrhosis and alcoholic cirrhosis were 39% (range 0%-78%) and 36% (range 12% to 41%), respectively. The pooled incidence of variceal rebleeding in the TIPS group was significantly lower than that in the EVS group (HR = 0.3, 0.35, 95%CI: 0.17-0.71, P = 0.004). However, the risk of the development of any degree of HE was significantly increased in the TIPS group (OR = 15.97, 95%CI: 3.61-70.68). The pooled HR of survival was 1.26 (95%CI: 0.76-2.09, P = 0.36). No inter-trial heterogeneity was observed among these analyses. CONCLUSION: The improved effect of TIPS in the prevention of GV rebleeding is associated with an increased risk of HE. There is no survival difference between the TIPS and EVS groups. Further studies are needed to evaluate the survival benefit of TIPS in cirrhotic patients with GV bleeding. PMID:24868490

  10. Passively Shunted Piezoelectric Damping of Centrifugally-Loaded Plates

    NASA Technical Reports Server (NTRS)

    Duffy, Kirsten P.; Provenza, Andrew J.; Trudell, Jeffrey J.; Min, James B.

    2009-01-01

    Researchers at NASA Glenn Research Center have been investigating shunted piezoelectric circuits as potential damping treatments for turbomachinery rotor blades. This effort seeks to determine the effects of centrifugal loading on passively-shunted piezoelectric - damped plates. Passive shunt circuit parameters are optimized for the plate's third bending mode. Tests are performed both non-spinning and in the Dynamic Spin Facility to verify the analysis, and to determine the effectiveness of the damping under centrifugal loading. Results show that a resistive shunt circuit will reduce resonant vibration for this configuration. However, a tuned shunt circuit will be required to achieve the desired damping level. The analysis and testing address several issues with passive shunt circuit implementation in a rotating system, including piezoelectric material integrity under centrifugal loading, shunt circuit implementation, and tip mode damping.

  11. Late calcification and rupture: a rare complication of ventriculoperitoneal shunting.

    PubMed

    Kural, Cahit; Kirik, Alparslan; Pusat, Serhat; Senturk, Tolga; Izci, Yusuf

    2012-01-01

    A 10-year old boy who had undergone a ventriculoperitoneal (V/P) shunt because of hydrocephalus at 10 days of age was doing well until 20 days ago, when he began to experience headache and seizures. CT scan revealed dilated lateral ventricles and calcification at the shunt site. X-rays showed an unusual calcification pattern around the shunt tube and rupture of the tube between the mastoid bone and clavicle. The patient underwent surgery and the shunt was changed completely. The ventricles became small in the follow-up. Even though V/P shunts may induce fibrous tissue formation and calcification around the tube, there are a few cases of shunt rupture and calcification of shunts in the literature. Possible mechanisms of the rupture and calcification are discussed in this paper. PMID:23208915

  12. Resistively shunted piezocomposites for passive damping

    NASA Astrophysics Data System (ADS)

    Yarlagadda, Shridhar

    The goal of this work was to theoretically model, fabricate and characterize 3-3 coupled piezocomposite structures, using shunted piezoelectric fibers with integrated resistive shunting. Advantages and disadvantages of the different shunted piezocomposite configurations were examined from both modeling and fabrication points of view. Two configurations of practical interest were chosen for detailed study: (1) piezoelectric whiskers in a resistive matrix, and (2) piezoelectric whiskers in a layer of epoxy and shunted with a thin film resistive coating. Two different models were developed: a "smeared" dynamic model and a finite element model. Composite beam theory was modified to include shunted piezoelectric behavior and governing equations and boundary conditions were formulated. For the finite element model, a shunted piezoelectric element was formulated and the discretized governing equations were converted to state-space form. Modeling results demonstrated the possibility of modal loss factors as high as 10% in a single mode, for an effective piezoelectric volume fraction of 25%, as well the ability to tailor achievable levels of damping. Non-linear potential variation and local effects were successfully modeled. The critical parameters affecting modal damping were piezoelectric whisker volume fraction, shunt resistance, structural geometry and the location of whiskers. Experimental efforts involved fabrication of shunted piezocomposites for both configurations. Using chopped continuous poled PZT-5H fibers; a whisker/resistive matrix composite was successfully fabricated. For the resistive matrix case, matrix conductivity was a function of filler volume fraction and showed the percolation effect. However, the dielectric constant of the matrix also increased significantly (factor of 1000) at the design filler volume fraction, which drastically altered the electrical behavior of the piezocomposite from the designed case. The change in dielectric constant appeared

  13. Jugular Foramen Arteriovenous Shunt with Subarachnoid Hemorrhage

    PubMed Central

    Rodesch, G.; Comoy, J.; Hurth, M.; Lasjaunias, P.

    1991-01-01

    The authors report the case of a 37-year-old man with an extracerebral arteriovenous fistula at the skull base, revealed by subarachnoid and intraventricular hemorrhage. The malformation was fed by the neuromeningeal trunk of the ascending pharyngeal artery and drained into left laterobulbar veins. Embolization with bucrylate was performed and occluded totally the shunting zone. A 1-year follow-up angiogram confirmed the good stability of the result, the patient being asymptomatic. This case emphasizes the quality of results that can be obtained with bucrylate in arterioverious fistulas presenting with hemorrhage. It confirms that the external carotid artery must be studied when dealing with intracranial hemorrhage. On the other hand, magnetic resonance imaging and angiography may depict vascular abnormalities but do not always indicate the shunting area, thus the pathologic type of the malformation. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 5p136-b PMID:17170835

  14. Active shunt capacitance cancelling oscillator circuit

    DOEpatents

    Wessendorf, Kurt O.

    2003-09-23

    An oscillator circuit is disclosed which can be used to produce oscillation using a piezoelectric crystal, with a frequency of oscillation being largely independent of any shunt capacitance associated with the crystal (i.e. due to electrodes on the surfaces of the crystal and due to packaging and wiring for the crystal). The oscillator circuit is based on a tuned gain stage which operates the crystal at a frequency, f, near a series resonance frequency, f.sub.S. The oscillator circuit further includes a compensation circuit that supplies all the ac current flow through the shunt resistance associated with the crystal so that this ac current need not be supplied by the tuned gain stage. The compensation circuit uses a current mirror to provide the ac current flow based on the current flow through a reference capacitor that is equivalent to the shunt capacitance associated with the crystal. The oscillator circuit has applications for driving piezoelectric crystals for sensing of viscous, fluid or solid media by detecting a change in the frequency of oscillation of the crystal and a resonator loss which occur from contact of an exposed surface of the crystal by the viscous, fluid or solid media.

  15. Bobble-head doll syndrome associated with subduroperitoneal shunt malfunction.

    PubMed

    Ahn, Y; Cho, B K; Wang, K C

    1997-04-01

    Bobble-head doll syndrome is known to be associated with aqueductal stenosis or cystic lesions of the III ventricle. The direction of movement is usually vertical. In the literature, only five cases of purely horizontal movement have been reported. Bobble-head doll syndrome manifested as a sign of shunt malfunction has been described in one case with a ventriculoperitoneal shunt. The authors report on a 10-year-old boy who showed subduroperitoneal shunt malfunction associated with horizontal bobble-head doll syndrome. The head bobbing disappeared immediately after shunt revision. Unlike the previously reported cases, in the present case the lesion was asymmetric, though the significance of this for the lateral movement is not clear. This case also showed more marked ventricular dilatation on subduroperitoneal shunt malfunction than in the pre-shunt state. The underlying mechanism of the ventricular dilatation is unknown. PMID:9202861

  16. Alternative uses for the subgaleal shunt in pediatric neurosurgery.

    PubMed

    Tubbs, R Shane; Smyth, Matthew D; Wellons, John C; Blount, Jeffrey P; Grabb, Paul A; Oakes, W Jerry

    2003-07-01

    The subgaleal shunt has been used for the temporary bypass of the normal cerebrospinal fluid (CSF) pathways. We retrospectively reviewed all subgaleal shunts placed at the Children's Hospital, Birmingham, Ala., USA, from 1997 to the present and examined all uses (e.g. indication, length of follow-up) of the subgaleal shunt outside its use for temporary CSF diversion in premature infants with intraventricular hemorrhage and subsequent hydrocephalus. The average length of survival of the primary subgaleal shunt in this population was 32.2 days. We have had good success with subgaleal shunts in children with malignant brain tumors, intraventricular abscesses, chronic truncal wounds, chronic subdural hygromas and meningitis. However, the greatest utility has been in those scenarios in which the peritoneal cavities were not currently, but with time would be, candidates for distal shunt implantation. Examples of these instances are patients with hydrocephalus and necrotizing enterocolitis or hydrocephalus and preoperative abdominal wall pathology such as omphalocele. PMID:12784073

  17. Histologic classification of gliomas.

    PubMed

    Perry, Arie; Wesseling, Pieter

    2016-01-01

    Gliomas form a heterogeneous group of tumors of the central nervous system (CNS) and are traditionally classified based on histologic type and malignancy grade. Most gliomas, the diffuse gliomas, show extensive infiltration in the CNS parenchyma. Diffuse gliomas can be further typed as astrocytic, oligodendroglial, or rare mixed oligodendroglial-astrocytic of World Health Organization (WHO) grade II (low grade), III (anaplastic), or IV (glioblastoma). Other gliomas generally have a more circumscribed growth pattern, with pilocytic astrocytomas (WHO grade I) and ependymal tumors (WHO grade I, II, or III) as the most frequent representatives. This chapter provides an overview of the histology of all glial neoplasms listed in the WHO 2016 classification, including the less frequent "nondiffuse" gliomas and mixed neuronal-glial tumors. For multiple decades the histologic diagnosis of these tumors formed a useful basis for assessment of prognosis and therapeutic management. However, it is now fully clear that information on the molecular underpinnings often allows for a more robust classification of (glial) neoplasms. Indeed, in the WHO 2016 classification, histologic and molecular findings are integrated in the definition of several gliomas. As such, this chapter and Chapter 6 are highly interrelated and neither should be considered in isolation. PMID:26948349

  18. Urinary bladder calculi complicating ventriculo-vesical shunt.

    PubMed

    Shahul Hameed, A S; Yousaf, I; Choudhari, K A

    2005-10-01

    A rare case of vesical calculi complicating the procedure of ventriculo-vesical shunt is presented. In addition to highlighting technical difficulties in placing shunt catheters into the urinary system, the potential complications are discussed. We consider this route of cerebrospinal fluid(CSF) diversion less physiological compared with the peritoneal, pleural or the venous sites, and discourage use of the urinary bladder as the drainage site for the shunting of CSF. PMID:16455572

  19. Controlling hysteresis in superconducting constrictions with a resistive shunt

    NASA Astrophysics Data System (ADS)

    Kumar, Nikhil; Winkelmann, C. B.; Biswas, Sourav; Courtois, H.; Gupta, Anjan K.

    2015-07-01

    We demonstrate control of the thermal hysteresis in superconducting constrictions by adding a resistive shunt. In order to prevent thermal relaxation oscillations, the shunt resistor is placed in close proximity to the constriction, making the inductive current-switching time smaller than the thermal equilibration time. We investigate the current-voltage characteristics of the same constriction with and without the shunt-resistor. The widening of the hysteresis-free temperature range is explained on the basis of a simple model.

  20. Semi-shunt field emission in electronic devices

    NASA Astrophysics Data System (ADS)

    Karpov, V. G.; Shvydka, Diana

    2014-08-01

    We introduce a concept of semi-shunts representing needle shaped metallic protrusions shorter than the distance between a device electrodes. Due to the lightening rod type of field enhancement, they induce strong electron emission. We consider the corresponding signature effects in photovoltaic applications; they are: low open circuit voltages and exponentially strong random device leakiness. Comparing the proposed theory with our data for CdTe based solar cells, we conclude that stress can stimulate semi-shunts' growth making them shunting failure precursors. In the meantime, controllable semi-shunts can play a positive role mitigating the back field effects in photovoltaics.

  1. A compact, coaxial shunt current diagnostic for X pinches

    NASA Astrophysics Data System (ADS)

    Wang, Liangping; Zhang, Jinhai; Li, Mo; Zhang, Xinjun; Zhao, Chen; Zhang, Shaoguo

    2015-08-01

    A compact coaxial shunt was applied in X-pinches experiments on Qiangguang pulsed power generator. The coaxial shunt was designed to have a compact construction for smaller inductance and more, for conveniently assembling upon the X pinch load structure. The coaxial shunt is also a cheap current probe and was easily built by research groups. The shunt can monitor a 100 kA high current with a 100 ns rise time. The calibration results showed that the probe used in the experiments has a resistance of 3.2 mΩ with an uncertainty of 3%, and its response time to the step signal is less than 7 ns.

  2. Superconducting fault current-limiter with variable shunt impedance

    DOEpatents

    Llambes, Juan Carlos H; Xiong, Xuming

    2013-11-19

    A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

  3. Results of portal systemic shunts in Budd-Chiari syndrome.

    PubMed Central

    Vons, C; Smadja, C; Bourstyn, E; Szekely, A M; Bonnet, P; Franco, D

    1986-01-01

    Nine patients with Budd-Chiari syndrome (BCS) were treated by a portal systemic shunt. One had thrombosis of the superior mesenteric vein (SMV) and another had complete obstruction of the retrohepatic inferior vena cava (IVC). All other patients had a marked stenosis of the retrohepatic IVC with caval pressure ranging from 12 to 24 mmHg (mean: 17 mmHg). Seven patients had an interposition mesocaval shunt using an autologous jugular vein. The patient with a thrombosed SMV had a portoatrial shunt. The patient with an obstructed IVC had a cavoatrial shunt after an erroneous portacaval shunt had failed to relieve ascites. There were no operative deaths and no major postoperative complications. One patient died 19 months after operation of acute leukemia complicating polycythemia rubra vera. All other patients were alive and well 8 months to 6 years after operation. None of them had encephalopathy. These results suggest several comments: Portal systemic shunts are a good treatment for BCS and have a low operative risk. The mesocaval shunt is an efficient procedure, even when there is stenosis of the IVC with high caval pressure; shunts to the right atrium should be performed only in the case of complete obstruction or inaccessibility of the IVC. The long-term prognosis is excellent, except in patients with potential malignancies. Therefore, portal systemic shunts should be indicated early in patients with symptomatic BCS. PMID:3963896

  4. Ventriculoperitoneal shunt malfunction caused by proximal catheter fat obstruction.

    PubMed

    Mizrahi, Cezar José; Spektor, Sergey; Margolin, Emil; Shoshan, Yigal; Ben-David, Eliel; Cohen, José E; Moscovici, Samuel

    2016-08-01

    Ventriculoperitoneal (VP) shunt placement is the mainstay of treatment for hydrocephalus, yet shunts remain vulnerable to a variety of complications. Although fat droplet migration into the subarachnoid space and cerebrospinal fluid pathways following craniotomy has been observed, a VP shunt obstruction with fat droplets has never been reported to our knowledge. We present the first reported case of VP shunt catheter obstruction by migratory fat droplets in a 55-year-old woman who underwent suboccipital craniotomy for removal of a metastatic tumor of the left medullocerebellar region, without fat harvesting. A VP shunt was inserted 1month later due to communicating hydrocephalus. The patient presented with gait disturbance, intermittent confusion, and pseudomeningocele 21days after shunt insertion. MRI revealed retrograde fat deposition in the ventricular system and VP shunt catheter, apparently following migration of fat droplets from the fatty soft tissue of the craniotomy site. Spinal tap revealed signs of aseptic meningitis. Steroid treatment for aseptic "lipoid" meningitis provided symptom relief. MRI 2months later revealed partial fat resorption and resolution of the pseudomeningocele. VP shunt malfunction caused by fat obstruction of the ventricular catheter should be acknowledged as a possible complication in VP shunts after craniotomy, even in the absence of fat harvesting. PMID:27010421

  5. Impedance Changes Indicate Proximal Ventriculoperitoneal Shunt Obstruction In Vitro.

    PubMed

    Basati, Sukhraaj; Tangen, Kevin; Hsu, Ying; Lin, Hanna; Frim, David; Linninger, Andreas

    2015-12-01

    Extracranial cerebrospinal fluid (CSF) shunt obstruction is one of the most important problems in hydrocephalus patient management. Despite ongoing research into better shunt design, robust and reliable detection of shunt malfunction remains elusive. The authors present a novel method of correlating degree of tissue ingrowth into ventricular CSF drainage catheters with internal electrical impedance. The impedance based sensor is able to continuously monitor shunt patency using intraluminal electrodes. Prototype obstruction sensors were fabricated for in-vitro analysis of cellular ingrowth into a shunt under static and dynamic flow conditions. Primary astrocyte cell lines and C6 glioma cells were allowed to proliferate up to 7 days within a shunt catheter and the impedance waveform was observed. During cell ingrowth a significant change in the peak-to-peak voltage signal as well as the root-mean-square voltage level was observed, allowing the impedance sensor to potentially anticipate shunt malfunction long before it affects fluid drainage. Finite element modeling was employed to demonstrate that the electrical signal used to monitor tissue ingrowth is contained inside the catheter lumen and does not endanger tissue surrounding the shunt. These results may herald the development of "next generation" shunt technology that allows prediction of malfunction before it affects patient outcome. PMID:25014951

  6. Over-drainage and persistent shunt-dependency in patients with idiopathic intracranial hypertension treated with shunts and bariatric surgery

    PubMed Central

    Roth, Jonathan; Constantini, Shlomi; Kesler, Anat

    2015-01-01

    Background: Idiopathic intracranial hypertension (IIH) may lead to visual impairment. Shunt surgery is indicated for refractory IIH-related symptoms that persist despite medical treatment, or those presenting with significant visual decline. Obesity is a risk factor for IIH; a reduction in weight has been shown to improve papilledema. Bariatric surgery (BS) has been suggested for treating IIH associated with morbid obesity. In this study, we describe a high rate of over-drainage (OD) seen in patients following shunts and BS. Methods: The study cohort includes 13 patients with IIH that underwent shunt surgery for treatment of the IIH-related symptoms. Six patients underwent BS in addition to the shunt surgery (but not concomitantly). Seven patients had only shunt surgeries with no BS. Data were collected retrospectively. Results: BS effectively led to weight reduction (body mass index decreasing from 43 ± 4 to 28 ± 5). Patients undergoing BS had 1–6 (2.5 ± 1.9) shunt revisions for OD following BS, as opposed to 0–3 (1.4 ± 1.1) revisions prior to BS over similar time spans (statistically insignificant difference), and 0–6 (1.6 ± 2.5) revisions among the non-BS patients over a longer time span (statistically insignificant difference). Two patients in the BS group underwent shunt externalization and closure; however, they proved to be shunt-dependent. Conclusions: Patients with IIH that undergo shunt surgery and BS (not concomitantly) may suffer from OD symptoms, necessitating multiple shunt revisions, and valve upgrades. Despite BS being a valid primary treatment for some patients with IIH, among shunted patients, BS may not lead to resolution of IIH-related symptoms and patients may remain shunt-dependent. PMID:26713173

  7. [Histological techniques in oncodermatology].

    PubMed

    Chaput, B; Le Guellec, S; Courtade-Saïdi, M; Gangloff, D; Meresse, T; Chavoin, J-P; Grolleau, J-L; Garrido, I

    2012-04-01

    The skin oncology or "oncodermatology" requires a surgical treatment in most cases. For some surgeons, the oncodermatology takes a very important part of their practice. In the course of diagnostic and therapeutic of skin lesions, the pathologist plays now an essential role. He will guide our surgery. The techniques used by this specialist are numerous. Therefore, the objective of this paper is to review the different histological methods used to improve our management of skin tumors. PMID:22463986

  8. 49 CFR 236.60 - Switch shunting circuit; use restricted.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Switch shunting circuit; use restricted. 236.60 Section 236.60 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... Instructions: All Systems Track Circuits § 236.60 Switch shunting circuit; use restricted. Switch...

  9. 49 CFR 236.724 - Circuit, shunt fouling.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, shunt fouling. 236.724 Section 236.724 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, shunt fouling. The track circuit in the fouling section of a turnout, connected in multiple...

  10. 21 CFR 882.4545 - Shunt system implantation instrument.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Shunt system implantation instrument. 882.4545 Section 882.4545 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4545 Shunt system implantation instrument. (a) Identification....

  11. Internal carotid artery rupture caused by carotid shunt insertion

    PubMed Central

    Illuminati, Giulio; Caliò, Francesco G.; Pizzardi, Giulia; Vietri, Francesco

    2015-01-01

    Introduction Shunting is a well-accepted method of maintaining cerebral perfusion during carotid endarterectomy (CEA). Nonetheless, shunt insertion may lead to complications including arterial dissection, embolization, and thrombosis. We present a complication of shunt insertion consisting of arterial wall rupture, not reported previously. Presentation of case A 78-year-old woman underwent CEA combined with coronary artery bypass grafting (CABG). At the time of shunt insertion an arterial rupture at the distal tip of the shunt was detected and was repaired via a small saphenous vein patch. Eversion CEA and subsequent CABG completed the procedure whose postoperative course was uneventful. Discussion Shunting during combined CEA-CABG may be advisable to assure cerebral protection from possible hypoperfusion due to potential hemodynamic instability of patients with severe coronary artery disease. Awareness and prompt management of possible shunt-related complications, including the newly reported one, may contribute to limiting their harmful effect. Conclusion Arterial wall rupture is a possible, previously not reported, shunt-related complication to be aware of when performing CEA. PMID:26255001

  12. [Temporary vascular shunt technique for resource scarce environments].

    PubMed

    Ouattara, N; Mlynski, A; Pierret, C

    2011-10-01

    The purpose of this report is to describe a simple and reproducible technique for temporary vascular shunting. This technique is appropriate only for exceptional situations involving scant resource availability. It is not intended to replace conventional vascular shunting techniques. PMID:22235609

  13. Biosynthetic route towards saxitoxin and shunt pathway

    PubMed Central

    Tsuchiya, Shigeki; Cho, Yuko; Konoki, Keiichi; Nagasawa, Kazuo; Oshima, Yasukatsu; Yotsu-Yamashita, Mari

    2016-01-01

    Saxitoxin, the most potent voltage-gated sodium channel blocker, is one of the paralytic shellfish toxins (PSTs) produced by cyanobacteria and dinoflagellates. Recently, putative biosynthetic genes of PSTs were reported in these microorganisms. We previously synthesized genetically predicted biosynthetic intermediates, Int-A’ and Int-C’2, and also Cyclic-C’ which was not predicted based on gene, and identified them all in the toxin-producing cyanobacterium Anabaena circinalis (TA04) and the dinoflagellate Alexandrium tamarense (Axat-2). This study examined the incorporation of 15N-labeled intermediates into PSTs (C1 and C2) in A. circinalis (TA04). Conversions from Int-A’ to Int-C’2, from Int-C’2 to Cyclic-C’, and from Int-A’ and Int-C’2 to C1 and C2 were indicated using high resolution-LC/MS. However, Cyclic-C’ was not converted to C1 and C2 and was detected primarily in the extracellular medium. These results suggest that Int-A’ and Int-C’2 are genuine precursors of PSTs, but Int-C’2 converts partially to Cyclic-C’ which is a shunt product excreted to outside the cells. This paper provides the first direct demonstration of the biosynthetic route towards saxitoxin and a shunt pathway. PMID:26842222

  14. Flexural waves focusing through shunted piezoelectric patches

    NASA Astrophysics Data System (ADS)

    Yi, K.; Collet, M.; Ichchou, M.; Li, L.

    2016-07-01

    In this paper, we designed and analyzed a piezo-lens to focus flexural waves in thin plates. The piezo-lens is comprised of a host plate and piezoelectric arrays bonded on the surfaces of the plate. The piezoelectric patches are shunted with negative capacitance circuits. The effective refractive indexes inside the piezo-lens are designed to fit a hyperbolic secant distribution by tuning the negative capacitance values. A homogenized model of a piezo-mechanical system is adopted in the designing process of the piezo-lens. The wave focusing effect is studied by the finite element method. Numerical results show that the piezo-lens can focus flexural waves by bending their trajectories, and is effective in a large frequency band. The piezo-lens has the ability to focus flexural waves at different locations by tuning the shunting negative capacitance values. The piezo-lens is shown to be effective for flexural waves generated by different types of sources.

  15. Shunt attachment and method for interfacing current collection systems

    DOEpatents

    Denney, Paul E.; Iyer, Natraj C.; Hannan, III, William F.

    1992-01-01

    A composite brush to shunt attachment wherein a volatile component of a composite but mostly metallic brush, used for current collection purposes, does not upon welding or brazing, adversely affect the formation of the interfacial bond with a conductive shunt which carries the current from the zone of the brush. The brush to shunt attachment for a brush material of copper-graphite composite and a shunt of copper, or substituting silver for copper as an alternative, is made through a hot isostatic pressing (HIP). The HIP process includes applying high pressure and temperature simultaneously at the brush to shunt interface, after it has been isolated or canned in a metal casing in which the air adjacent to the interface has been evacuated and the interfacial area has been sealed before the application of pressure and temperature.

  16. Shunt attachment and method for interfacing current collection systems

    DOEpatents

    Denney, P.E.; Iyer, N.C.; Hannan, W.F. III.

    1992-12-08

    A composite brush to shunt attachment wherein a volatile component of a composite but mostly metallic brush, used for current collection purposes, does not upon welding or brazing, adversely affect the formation of the interfacial bond with a conductive shunt which carries the current from the zone of the brush. The brush to shunt attachment for a brush material of copper-graphite composite and a shunt of copper, or substituting silver for copper as an alternative, is made through a hot isostatic pressing (HIP). The HIP process includes applying high pressure and temperature simultaneously at the brush to shunt interface, after it has been isolated or canned in a metal casing in which the air adjacent to the interface has been evacuated and the interfacial area has been sealed before the application of pressure and temperature. 6 figs.

  17. Portasystemic shunt fraction quantification with colonic iodine-123 iodoamphetamine

    SciTech Connect

    Yen, C.K.; Pollycove, M.; Crass, R.; Lin, T.H.; Baldwin, R.; Lamb, J.

    1986-08-01

    Portasystemic shunting was quantified in dogs with (/sup 123/I)iodoamphetamine (IMP) administered transrectally into the colon and monitored externally with a gamma camera. IMP was absorbed rapidly and unchanged from the colon. After direct injection into the portal vein, IMP was almost completely extracted by the liver on the first pass, and the washout half-life was approximately 60 min. Based on these kinetic data, computer simulation of this biologic system was carried out. Errors associated with simplified models are calculated. The simplest model with insignificant error, which assumed that the tracer behaved like microspheres, was used to quantitate portasystemic shunt fraction in animals with surgically created shunts. Results were compared with the standard of /sup 99m/Tc-labeled macroaggregated albumin infused into a branch of inferior mesenteric vein. For shunt fractions ranging from 0 to 100%, an excellent correlation was seen, indicating that this approach is potentially a simple, noninvasive method of portasystemic shunt fraction quantification.

  18. Management of Ventriculo-Peritoneal Shunts in the Paediatric Population

    PubMed Central

    Low, David; Drake, James M; Seow, Wan Tew; Ng, Wai Hoe

    2010-01-01

    The treatment of hydrocephalus is a challenging one. The development of shunt devices have greatly improved the survival and quality of life of paediatric patients with hydrocephalus; however, shunt dysfunction is a common problem which represents a significant scope of work for paediatric neurosurgeons with shunt failures occuring in up to 40 to 50% of patients during the first two years after shunt surgery. Numerous pathologies ranging from congenital to acquired conditions can result in the development of hydrocephalus in the paediatric population. Obstruction of proximal or distal catheter ends, misplacement, infections and over drainage are some of the common problems accounting for shunt failures. We discussed some of the pertinent problems and nuances involved in treatment of paediatric hydrocephalus with VPS as well as to review the role of endoscopic procedures as an alternative to VPS. PMID:22028738

  19. Parylene MEMS patency sensor for assessment of hydrocephalus shunt obstruction.

    PubMed

    Kim, Brian J; Jin, Willa; Baldwin, Alexander; Yu, Lawrence; Christian, Eisha; Krieger, Mark D; McComb, J Gordon; Meng, Ellis

    2016-10-01

    Neurosurgical ventricular shunts inserted to treat hydrocephalus experience a cumulative failure rate of 80 % over 12 years; obstruction is responsible for most failures with a majority occurring at the proximal catheter. Current diagnosis of shunt malfunction is imprecise and involves neuroimaging studies and shunt tapping, an invasive measurement of intracranial pressure and shunt patency. These patients often present emergently and a delay in care has dire consequences. A microelectromechanical systems (MEMS) patency sensor was developed to enable direct and quantitative tracking of shunt patency in order to detect proximal shunt occlusion prior to the development of clinical symptoms thereby avoiding delays in treatment. The sensor was fabricated on a flexible polymer substrate to eventually allow integration into a shunt. In this study, the sensor was packaged for use with external ventricular drainage systems for clinical validation. Insights into the transduction mechanism of the sensor were obtained. The impact of electrode size, clinically relevant temperatures and flows, and hydrogen peroxide (H2O2) plasma sterilization on sensor function were evaluated. Sensor performance in the presence of static and dynamic obstruction was demonstrated using 3 different models of obstruction. Electrode size was found to have a minimal effect on sensor performance and increased temperature and flow resulted in a slight decrease in the baseline impedance due to an increase in ionic mobility. However, sensor response did not vary within clinically relevant temperature and flow ranges. H2O2 plasma sterilization also had no effect on sensor performance. This low power and simple format sensor was developed with the intention of future integration into shunts for wireless monitoring of shunt state and more importantly, a more accurate and timely diagnosis of shunt failure. PMID:27589973

  20. Muzzle shunt augmentation of conventional railguns

    SciTech Connect

    Parker, J.V. . Physics Div.)

    1991-01-01

    This paper reports on augmentation which is a technique for reducing the armature current and hence the armature power dissipation in a plasma armature railgun. In spite of the advantages, no large augmented railguns have been built, primarily due to the mechanical and electrical complexity introduced by the extra conductors required. it is possible to achieve some of the benefits of augmentation in a conventional railgun by diverting a fraction {phi} of the input current through a shunt path at the muzzle of the railgun. In particular, the relation between force and armature current is the same as that obtained in an n-turn, series-connected augmented railgun with n = 1/(1 {minus} {phi}). The price of this simplification is a reduction in electrical efficiency and some additional complexity in the external electrical system.

  1. Ultrasound-Guided Retrieval and Position Replacement of a Dislodged Fetal Pleuro-Amniotic Shunt: A Novel Approach for a Known Complication of Feto-Amniotic Shunting.

    PubMed

    Adams, Tracy M; Kunzier, Nadia B; Chavez, Martin R; Vintzileos, Anthony M

    2016-01-01

    Untreated fetal pleural effusion can cause significant perinatal morbidity and mortality. Treatment of pleural effusions with pleuro-amniotic shunting has been shown to improve outcomes. Pleuro-amniotic shunting is associated with complications including ruptured membranes, preterm labor and shunt dislodgement into either the amniotic cavity or the fetal thorax. Shunt dislodgement into the thoracic cavity can cause prenatal complications from the shunt itself or may necessitate neonatal surgery for removal. We present a case where a novel ultrasound-guided technique was used to replace the dislodged pleural shunt in utero, thereby effectively draining the effusion while simultaneously obviating the need for neonatal surgery and decreasing possible perinatal complications. PMID:25660293

  2. 49 CFR 236.309 - Loss of shunt protection; where required.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Loss of shunt protection; where required. 236.309... Standards § 236.309 Loss of shunt protection; where required. (a) A loss of shunt of 5 seconds or less shall not permit an established route to be changed at an automatic interlocking. (b) A loss of shunt of...

  3. Nuclear Medicine to Evaluate Complications of Cerebral Shunts: Two Cases and Review of Literature

    PubMed Central

    Vettiyil, Beth; Bessette, Sabrina; McQuiston, Samuel; Greiner, Francis

    2015-01-01

    We present two cases of cerebral shunts - a ventriculopleural shunt and a ventriculoperitoneal shunt, with their associated complications. We also hope to provide a comprehensive literature review on various imaging modalities, including nuclear medicine studies in evaluating cerebral shunt complications. PMID:26420995

  4. Ion beam sputter-etched ventricular catheter for hydrocephalus shunt

    NASA Technical Reports Server (NTRS)

    Banks, B. A. (Inventor)

    1983-01-01

    A cerebrospinal fluid shunt in the form of a ventricular catheter for controlling the condition of hydrocephalus by relieving the excessive cerebrospinal fluid pressure is described. A method for fabrication of the catheter and shunting the cerebral fluid from the cerebral ventricles to other areas of the body is also considered. Shunt flow failure occurs if the ventricle collapse due to improper valve function causing overdrainage. The ventricular catheter comprises a multiplicity of inlet microtubules. Each microtubule has both a large openings at its inlet end and a multiplicity of microscopic openings along its lateral surfaces.

  5. Pollutants removal in subsurface infiltration systems by shunt distributing wastewater with/without intermittent aeration under different shunt ratios.

    PubMed

    Pan, Jing; Yuan, Fang; Zhang, Yang; Huang, Linli; Yu, Long; Zheng, Fanping; Cheng, Fan; Zhang, Jiadi

    2016-10-01

    Matrix dissolved oxygen (DO), removal of COD, TP and nitrogen in subsurface infiltration systems (SISs), named SIS A (without intermittent aeration and shunt distributing wastewater), SIS B (with shunt distributing wastewater) and SIS C (with intermittent aeration and shunt distributing wastewater) were investigated. Aerobic conditions were developed in 50cm depth and anoxic or anaerobic conditions were not changed in 80 and 110cm depth by intermittent aeration. Under appropriate shunt ratios, shunt distributing wastewater improved denitrification and had little influence on COD, TP and NH3-N removal. Under the optimal shunt ratio of 1:2 for SIS C, high average removal rates of COD (90.06%), TP (93.17%), NH3-N (88.20%) and TN (85.79%) were obtained, which were higher than those in SIS A (COD: 82.56%, TP: 92.76%, NH3-N: 71.08%, TN: 49.24%) and SIS B (COD: 81.12%, TP: 92.58%, NH3-N: 69.14%, TN: 58.73%) under the optimal shunt ratio of 1:3. PMID:27347804

  6. Postpriapism erectile dysfunction and shunt-related urethral stricture: long-term morbidity after proximal shunt for ischaemic priapism

    PubMed Central

    Bello, Jibril Oyekunle

    2014-01-01

    Recent guidelines have advocated for step-wise treatment of increasing invasiveness in the management of ischaemic priapism though with low-level evidences. In the past, proximal shunts were favoured as first-line treatment. We present an African man who had proximal shunt (cavernoso-spongiosal) three decades ago for ischaemic priapism and subsequently had long-term morbidity over the three decades with adverse effect on his quality of life. Recent guidelines appear to be sound despite their limitations and more invasive cavernoso-spongiosal shunts may be associated with significant long-term morbidities and poor quality of life. PMID:25709730

  7. Use of cine phase-contrast MRI in the assessment of distal splenorenal shunt function.

    PubMed

    Cabassa, Paolo; Ravanelli, Marco; Alberti, Daniele; Maroldi, Roberto

    2012-06-01

    Magnetic resonance imaging (MRI) features of a surgical splenorenal shunt in a 28-year-old girl are described. The woman underwent color doppler ultrasonography during follow up for the shunt, which was inconclusive. MR was used to investigate the function of the shunt. Velocity and flow direction in splanchnic vessels and in the shunt were evaluated using cine fast phase-contrast sequences. MR findings could be of help in the evaluation of patients undergoing surgical shunts during follow up. PMID:22405982

  8. A case of breast cancer involving a ventriculoperitoneal shunt.

    PubMed

    Kamei, Mirei; Kikuchi, Nobuyuki; Ichimura, Homare; Chujo, Masao; Takahashi, Yoshiaki; Sugio, Kenji

    2016-12-01

    An 84-year-old woman was examined for an enlargement of an induration in the left breast. A ventriculoperitoneal shunt had been placed for postoperative normal pressure hydrocephalus of a cerebral hemorrhage, and it had penetrated the mass according to the computed tomography findings. Breast cancer was diagnosed after a close examination; however, close observation was selected because her family rejected treatment. She developed somnolence 7 months after the initial examination, and ventricular dilatation and expansion of the low-density region around the ventricle were noted on computed tomography, suggesting that the enlarged tumor had excluded the shunt and caused obstruction. The growth of breast carcinoma involving a shunt tube can be the cause of obstruction of a ventriculoperitoneal shunt. Our findings suggest that a breast lesion should be evaluated at both pre- and postoperation. PMID:26943684

  9. 21 CFR 874.3850 - Endolymphatic shunt tube with valve.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3850 Endolymphatic shunt... of a pressure-limiting valve associated with a tube intended to be implanted in the inner ear...

  10. 21 CFR 874.3850 - Endolymphatic shunt tube with valve.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3850 Endolymphatic shunt... of a pressure-limiting valve associated with a tube intended to be implanted in the inner ear...

  11. 21 CFR 874.3850 - Endolymphatic shunt tube with valve.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3850 Endolymphatic shunt... of a pressure-limiting valve associated with a tube intended to be implanted in the inner ear...

  12. 21 CFR 874.3850 - Endolymphatic shunt tube with valve.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3850 Endolymphatic shunt... of a pressure-limiting valve associated with a tube intended to be implanted in the inner ear...

  13. 21 CFR 874.3850 - Endolymphatic shunt tube with valve.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3850 Endolymphatic shunt... of a pressure-limiting valve associated with a tube intended to be implanted in the inner ear...

  14. 8. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

  15. 5. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

  16. 6. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

  17. 4. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

  18. 7. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

  19. 9. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

  20. 21 CFR 876.5955 - Peritoneo-venous shunt.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Identification. A peritoneo-venous shunt is an implanted device that consists of a catheter and a pressure activated one-way valve. The catheter is implanted with one end in the peritoneal cavity and the other in...

  1. 21 CFR 876.5955 - Peritoneo-venous shunt.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Identification. A peritoneo-venous shunt is an implanted device that consists of a catheter and a pressure activated one-way valve. The catheter is implanted with one end in the peritoneal cavity and the other in...

  2. 21 CFR 876.5955 - Peritoneo-venous shunt.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Identification. A peritoneo-venous shunt is an implanted device that consists of a catheter and a pressure activated one-way valve. The catheter is implanted with one end in the peritoneal cavity and the other in...

  3. 21 CFR 876.5955 - Peritoneo-venous shunt.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Identification. A peritoneo-venous shunt is an implanted device that consists of a catheter and a pressure activated one-way valve. The catheter is implanted with one end in the peritoneal cavity and the other in...

  4. Percutaneous ultrasound-guided insertion of ventriculo-atrial shunts.

    PubMed

    McCracken, James Albert; Bahl, Anuj; McMullan, John

    2016-08-01

    Ventriculo-atrial (VA) shunts have been in use for >60 years but less frequently so of late. This is due to a combination of the risk of cardiac complications, lack of expertise and a lengthy operation. We present our consecutive prospective series of 10 VA shunts inserted using a percutaneous method employing the Sonowand Invite™ neuronavigation system for both the distal and proximal catheters, over a 13-month period. We had two complications of cases needing revision, but our series highlights a safe and reproducible method of inserting a VA shunt. About 30% of the procedures were carried out by a trainee as the primary surgeon. This technique does not necessarily require the expertise of a complex hydrocephalus surgeon and is thus able to be in the armoury of any neurosurgeon needing to do a VA shunt procedure. The indications, operative data and outcomes of our patients are discussed. PMID:27025913

  5. Essentially nonlinear piezoelectric shunt circuits applied to mistuned bladed disks

    NASA Astrophysics Data System (ADS)

    Zhou, B.; Thouverez, F.; Lenoir, D.

    2014-04-01

    An essentially nonlinear piezoelectric shunt circuit is proposed for the practical realization of nonlinear energy sink, and then applied to a mistuned bladed disk for blade vibration reduction. First, the global dynamics of a single degree-of-freedom linear mechanical oscillator, coupled to an essentially nonlinear shunted piezoelectric attachment, is studied. Under certain conditions, the nonlinear targeted energy transfer, i.e. a fast, passive energy transfer from the mechanical oscillator to the nonlinear attachment is observed. A numerical method, referred to as the variable-coefficient harmonic balance method, is developed to calculate quasi-periodic responses arising in the electromechanical system under harmonic forcing. Characterized by the nonexistence of a resonance frequency, the essentially nonlinear shunt circuit is able to work robustly over a broad frequency band with a smaller inductance requirement compared with the linear resonant shunt circuit.

  6. [Sapheno-peritoneal shunt for the treatment of ascites].

    PubMed

    Nagy, Z; Gyurkovics, E; Kaliszky, P; Kupcsulik, P

    2001-08-01

    For the surgical treatment of drug resistant ascites caused by hepatic cirrhosis usually different types of valvular plastic tubes are used, implanted as peritoneo-venous shunts. These shunts drain the ascites into the jugular vein. In the 1st Surgical Department of the Semmelweis University Budapest we have performed 267 peritoneo-venous shunt operations. We introduced a new method using an autolog venous graft with a peritoneo-venous anastomosis, that drains the ascites into the saphenous, then femoral vein. So far we performed 5 such interventions. The early results suggest that sapheno-peritoneal shunt can be successfully used for treatment of ascites. With this operation complications of plastic grafts are avoidable. PMID:11550492

  7. [A simple peritoneovenous shunt in the treatment of chronic ascites].

    PubMed

    Pafko, P; Hladík, P

    2001-02-01

    The authors describe their own initial experience with a peritoneo-venous shunt in otherwise incurable ascites. It is a simple procedure which is more satisfactory than the formerly used technique of implantation of Le Veen's system. PMID:12881921

  8. In vitro flow measurements in ion sputtered hydrocephalus shunts

    NASA Technical Reports Server (NTRS)

    Cho, Y. I.; Back, L. H.

    1989-01-01

    This paper describes an experimental procedure for accurate measurements of the pressure-drop/flow rate relationship in hydrocephalus shunts. Using a fish-hook arrangement, small flow rates in a perforated ion-sputtered Teflon microtubule were measured in vitro in a pressured system and were correlated with pressure in the system. Results indicate that appropriate drainage rates could be obtained in the physiological range for hydrocephalus shunts.

  9. Paediatric ventriculoperitoneal shunt infection caused by Actinomyces neuii

    PubMed Central

    Anderson, Ian A; Jarral, Fazain; Sethi, Kavita; Chumas, Paul D

    2014-01-01

    We present the first reported case of ventriculoperitoneal shunt infection secondary to Actinomyces neuii in a paediatric patient. Our patient was managed with temporary shunt removal, intrathecal antibiotics and a prolonged course of intravenous and then oral antibiotics. She went on to make a complete recovery. Subsequent cerebrospinal fluid analysis at 5 months post-treatment demonstrated no evidence of residual infection. PMID:24859562

  10. Hearing Loss in Patients with Shunt-Treated Hydrocephalus.

    PubMed

    Panova, Margarita V; Geneva, Ina E; Madjarova, Kalina I; Bosheva, Miroslava N

    2015-01-01

    Hearing loss is a common manifestation of the long-term complications in patients with shunt treated hydrocephalus along with motor development disturbance, cognitive and visual impairment, epilepsy and endocrine disorders. The aim of the present study was to investigate the alterations of hearing in patients with shunt treated hydrocephalus of non-tumor etiology and at least one year after implantation of ventriculo-peritoneal shunt, as well as their impact on the quality of life of patients. The study included 70 patients (age range 1.25 years - 21.25 years) with shunted non-tumor hydrocephalus and at least one year after placement of the shunt system. Hearing alterations were proved by measuring the brainstem auditory evoked potentials (BAEP) for children up to 5 years of age and children with mental retardation; audiograms was used for children older than 5 years with normal neuro-psychological development (NPD). Of the 70 studied patients 17 (24%) had hearing loss (10 bilateral and 7-unilateral) and all of them had sensorineural hearing loss, which is associated with low weight at birth, posthemorrhagic hydrocephalus and brainstem symptoms at the time of diagnosis of hydrocephalus. Hearing pathology was found more often in shunt-treated patients with NPD retardation, poor functional status and low quality of life. Children with shunt-treated hydrocephalus have hearing loss of sensorineural type. Children with brain stem symptomatology at diagnosing hydrocephalus and children with post-hemorrhagic hydrocephalus show higher risk of hearing loss. Children with shunted hydrocephalus and hearing loss show lower NPD, lower quality of life and lower functional status. PMID:27180348

  11. [Angiological and neurological problems after shunt surgery in haemodialysis patients].

    PubMed

    Brittinger, W D

    2005-06-01

    Vascular access induced complications contribute to the morbidity of patients on regular dialysis treatment. Impaired peripheral perfusion, cardiac stress and nerve lesions are the most common of these complications. In the first part of this paper, angiological problems caused by creating arterio-venous shunts are described. Shunt volumes, blood circulation in the shunt arm and shunt-induced alterations of the circulatory blood volume are discussed as well as the conditions under which these parameters gain pathogenic importance. After describing the different shunt-specific circulatory disturbances in detail, the whole spectrum of preventive interventions are discussed. Based on the author's experience during more than four decades in this field, it is strongly recommended to treat even slight but clinically relevant circulatory disorders caused by arterio-venous shunts. The second part of this paper deals with neurological complications in access surgery for dialysis. The pathogenesis of these complications and the measures necessary to avoid them are discussed. Depending on the skin incision, 5 to 20 % of the patients with fistulas between the radial artery and the cephalic vein at the wrist show lesions of the superficial branch of the radial nerve or of the lateral forearm nerve branches. Fistulas with the ulnar artery at the dorsal aspect of the lower forearm frequently cause irritations of the ulnar nerve's superficial palmar branch. Fistulas with the basilic vein in the upper arm often are associated with lesions of the medial cutaneous nerve of the forearm, especially when the vein is "subcuticularized". Aside from these rather benign lesions, sometimes severe sensomotoric functional losses of the median, radial, and ulnar nerves occur, predominantly after implantation of vascular graft shunts in the upper arm. Similar nerve damage can also be observed in association with severe impairment of the peripheral perfusion caused by this type of shunt. Nerve

  12. Proximal ventricular shunt malfunctions in children: Factors associated with failure.

    PubMed

    Buster, Bryan E; Bonney, Phillip A; Cheema, Ahmed A; Glenn, Chad A; Conner, Andrew K; Safavi-Abbasi, Sam; Andrews, Mason B; Gross, Naina L; Mapstone, Timothy B

    2016-02-01

    Ventricular shunt failures and subsequent revisions are a significant source of patient morbidity. We conducted a review of pediatric patients undergoing placement or revision of ventricular shunts at our institution between January 2007 and December 2008. Patients were followed through to July 2014. Data collected included patient demographics, shunt history and indication for procedure, approach taken for shunt placement, and location of shunt tip in relation to the foramen of Monro. Univariate and multivariate analyses were conducted to identify factors associated with proximal failure. A total of 87 procedures were identified in 40 patients, consisting of 23 initial placements and 64 revisions. Thirty-nine proximal catheter malfunctions were identified. Indications for shunt placement included Chiari II malformation (33%) and intraventricular hemorrhage (33%). Mean follow-up period was 5.5 years. Median time to shunt failure was 1.57 years. In the multivariate model, younger age at placement was associated with decreased time to proximal failure (hazard ratio [HR]=0.80 per increasing year of age, 95% confidence interval [CI] 0.64-0.98). Both anterior approach (HR=0.39, 95% CI 0.23-0.67) and farther distance to foramen of Monro (HR=0.02 per increasing 10mm, 95% CI 0.00-0.22) were associated with increased time to proximal failure when the catheter tip was located within the contralateral lateral ventricle. Optimizing outcomes in patients with shunt-dependent hydrocephalus continues to be a challenge. Despite unsatisfactory outcomes, particularly in the pediatric population, few conclusions can be drawn from studies assessing operative variables. PMID:26601815

  13. First Report of Ventriculoperitoneal Shunt Infection due to Cyberlindnera fabianii

    PubMed Central

    Baghdadi, Jonathan; Hemarajata, Peera; Humphries, Romney; Kelesidis, Theodoros

    2015-01-01

    Fungal infections in the central nervous system (CNS) are associated with significant morbidity and death. Transient fungemia in immunocompetent patients without any other risk factors for fungemia has been suggested as a possible mechanism that may lead to serious fungal ventriculoperitoneal (VP) shunt infections, but evidence is lacking. The clinical spectrum, diagnosis, and optimal therapy of Cyberlindnera fabianii infections remain to be determined. We describe the first case of CNS infection due to C. fabianii that occurred in an immunocompetent adult with a VP shunt. Spontaneous translocation with yeast that is not part of the normal gastrointestinal flora in the setting of ingestion of multiple servings of a fermentation product was the likely source from which Cyberlindnera fabianii gained entrance into the VP shunt system, causing meningitis in this patient. The authors conclude that, in view of the high morbidity associated with yeast infection of the CNS, long-term antifungal therapy should be strongly considered in cases where the VP shunt cannot be completely removed. Transient fungemia may lead to invasive disease in an immunocompetent host with VP shunt, even in the absence of any other risk factors for fungemia and even after remote placement of the VP shunt. PMID:26618013

  14. Temporary arterial shunts to maintain limb perfusion after arterial injury: an animal study

    NASA Technical Reports Server (NTRS)

    Dawson, D. L.; Putnam, A. T.; Light, J. T.; Ihnat, D. M.; Kissinger, D. P.; Rasmussen, T. E.; Bradley, D. V. Jr

    1999-01-01

    BACKGROUND: Temporary shunt placement can quickly restore perfusion after extremity arterial injury. This study examined the adequacy of limb blood flow with shunt use, non-heparin-bonded shunt patency over prolonged periods, and the safety of this technique. METHODS: Common iliac arteries were divided and 4.0-mm Silastic Sundt shunts placed in 16 anesthetized pigs. Eight (group I) had shunts placed immediately; eight others (group II) were shunted after an hour of limb ischemia and hemorrhagic shock. Physiologic parameters and femoral artery blood flow in both hindlimbs were continuously monitored. Limb lactic acid generation, oxygen utilization, and hematologic and metabolic effects were serially evaluated for 24 hours. RESULTS: Shunts remained patent in 13 of 16 pigs. Shunts thrombosed in two group I animals because of technical errors, but functioned well after thrombectomy and repositioning. Patency could not be maintained in one animal that died from shock. Flow in group I shunted limbs was 57 (+/-11 SD) % of control. For group II animals in shock, shunted limb flow initially averaged 46 +/- 15% of control, but 4 hours after shunt placement, the mean limb blood flow was the same as in group I. Increased oxygen extraction compensated for the lower flow. Lactic acid production was not increased in comparison to control limbs. CONCLUSION: Shunts provided adequate flow in this model of extremity trauma. Correctly placed shunts stayed patent for 24 hours, without anticoagulation, if shunt placement followed resuscitation.

  15. Clinical, radiological, histological, and molecular characteristics of paediatric epithelioid glioblastoma

    PubMed Central

    Broniscer, Alberto; Tatevossian, Ruth G.; Sabin, Noah D.; Klimo, Paul; Dalton, James; Lee, Ryan; Gajjar, Amar; Ellison, David W.

    2014-01-01

    Aims A few case series in adults have described the characteristics of epithelioid glioblastoma (e-GB), one of the rarest variants of this cancer. We evaluated clinical, radiological, histological, and molecular characteristics in the largest series to date of paediatric e-GB. Methods Review of clinical characteristics and therapy, imaging studies, and histology was performed in patients younger than 22 years with e-GB seen at our institution over 15 years. Sequencing of hotspot mutations and FISH of relevant genes were undertaken. Results Median age at diagnosis of six patients was 7.6 years. Tumours originated in the cerebral cortex (n=2) or diencephalon (n=4). Three patients presented with acute, massive haemorrhage and three had leptomeningeal dissemination at diagnosis. Paediatric e-GB had the typical histological characteristics seen in adult tumours. Universal immunoreactivity for INI1 and lack of diverse protein expression were seen in all cases. One tumour had a chromosome 22q loss. Three tumours (50%) harboured a BRAF: p.V600E. One thalamic tumour had an H3F3A p.K27M. All patients received radiation therapy with (n=3) or without chemotherapy (n=3). All patients experienced tumour progression with a median survival of 169 days. One patient with non-metastatic disease had early leptomeningeal progression. Two patients had symptomatic tumour spread outside the central nervous system (CNS) through a ventriculo-peritoneal shunt. One additional patient had widespread metastases outside the CNS identified at autopsy. Conclusions Paediatric e-GBs are rare cancers with an aggressive behaviour that share histological and genetic characteristics with their adult counterparts. BRAF inhibition is a potential treatment for these tumours. PMID:24127995

  16. Laparoscopy for ventriculoperitoneal shunt implantation and revision surgery

    PubMed Central

    Pinto, Fernando Campos Gomes; de Oliveira, Matheus Fernandes

    2014-01-01

    Ventriculoperitoneal shunting (VPS) is a widely accepted technique for the treatment of hydrocephalus. The probability of shunt dysfunction is pretty high throughout life. Laparoscopy has become a valuable tool to perform VPS and treat abdominal complications. An electronic literature search was performed to reveal the published data relating laparoscopy and ventriculoperitoneal shunt in Medline, Embase, Scielo and Lilacs databases. The keywords employed were “laparoscopy” OR “laparoscopic surgery” AND “ventriculoperitoneal shunt” OR “shunt” AND “surgery” OR “implantation” OR “revision” OR “complication”. No high quality trials were developed comparing conventional laparotomic incision vs laparoscopic approach. Both approaches have evolved and currently there are less invasive options for laparotomy, like periumbilical small incisions; and for laparoscopy, like smaller and less incisions. Operating room time, blood loss and hospital stay may be potentially smaller in laparoscopic surgery and complications are probably the same as laparotomy. In revision surgery for abdominal complications after VPS, visualization of whole abdominal cavity is fundamental to address properly the problem and laparoscopic approach is valuable once it is safe, fast and much less invasive than laparotomy. Ventriculoperitoneal shunting is a widely accepted technique for the treatment of hydrocephalus. Laparoscopy assisted shunt surgery in selected cases might be a less invasive and more effective option for intrabdominal manipulation. The laparoscopic approach allows a better catheter positioning, lysis of fibrotic bundles and peritoneal inspection as well, without any additional complication. PMID:25228943

  17. A simplified technique of performing splenorenal shunt (Omar's technique).

    PubMed

    Shah, Omar Javed; Robbani, Irfan

    2005-01-01

    The splenorenal shunt procedure introduced by Robert Linton in 1947 is still used today in those regions of the world where portal hypertension is a common problem. However, because most surgeons find Linton's shunt procedure technically difficult, we felt that a simpler technique was needed. We present the surgical details and results of 20 splenorenal anastomosis procedures performed within a period of 30 months. Half of the patients (Group I) underwent Linton's conventional technique of splenorenal shunt; the other half (Group II) underwent a newly devised, simplified shunt technique. This new technique involves dissection of the fusion fascia of Toldt. The outcome of the 2 techniques was identical with respect to the reduction of preshunt portal pressure. However, our simplified technique was advantageous in that it significantly reduced the duration of surgery (P <0.001) and the amount of intraoperative blood loss (P <0.003). No patient died after either operation. Although Linton's splenorenal shunt is difficult and technically demanding, it is still routinely performed. The new technique described here, in addition to being simpler, helps achieve good vascular control, permits easier dissection of the splenic vein, enables an ideal anastomosis, decreases intraoperative blood loss, and reduces the duration of surgery. Therefore, we recommend the routine use of this simplified technique (Omar's technique) for the surgical treatment of portal hypertension. PMID:16429901

  18. Shunt site chronic calcified extradural hematoma: An avoidable complication

    PubMed Central

    Mishra, Sudhansu Sekhar; Satapathy, Mani Charan; Senapati, Satya Bhusan

    2014-01-01

    Extradural hematoma (EDH) after ventriculoperitoneal (VP) shunt procedure is a rare, dangerous but easily avoidable and manageable complication. It is more common in children and young adults presumably due to relatively lax adhesion of dura to calvarium. We report a case of an 18-year-old male with acqueductal stenosis who underwent VP shunt procedure. Three months later, a computed tomography (CT) scan was done for the complaints of intractable headache and altered sensorium which showed chronic calcified EDH near shunt site. The ventricular catheter was in position and the ventricles were decompressed. After surgical decompression of EDH his symptoms improved. We discuss the factors leading to formation of EDH, with stress on proper technique to prevent or minimize such an avoidable complication. PMID:25250078

  19. Material-induced shunts in multicrystalline silicon solar cells

    SciTech Connect

    Breitenstein, O. Bauer, J.; Rakotoniaina, J. P.

    2007-04-15

    By applying lock-in thermography imaging, light-beam-induced current imaging, electron-beam-induced current imaging at different stages of sample preparation, and infrared light microscopy in transmission mode, the physical nature of the dominant material-induced shunts in multicrystalline solar cells made from p-type silicon material has been investigated. It turns out that these shunts are due to silicon carbide (SiC) filaments, which grow preferentially in grain boundaries and cross the whole cell. These filaments are highly n-type doped, like the emitter layer on the surface of the cells. They are electrically connected both with the emitter and with the back contact, thereby producing internal shunts in the solar cell.

  20. Bidirectional Glenn shunt: a step in the right direction.

    PubMed

    Narayan, R; Balakrishnan, K G; Pillai, V R; Tharakan, J A; Titus, T; Kumar, R S

    1996-01-01

    Bidirectional Glenn (BDG) shunt was carried out in 14 patients (age range 1.5-22 years; mean 9.3 years) for a variety of congenital cyanotic heart diseases with decreased pulmonary blood flow. Postoperative cardiac catheterisation was carried out in 10 patients including successful balloon angioplasty of the shunt and LPA in one patient. There was a significant improvement in oxygen saturation and a drop in haematocrit level at follow-up. Doppler echocardiography studies in 13 patients revealed functioning shunts in all cases with low velocity continuous flow. Thus BDG is a useful palliative procedure and could be undertaken as the first stage of total cavopulmonary connection in high-risk Fontan groups where biventricular repair is not feasible. PMID:8908825

  1. Shunted Piezoelectric Vibration Damping Analysis Including Centrifugal Loading Effects

    NASA Technical Reports Server (NTRS)

    Min, James B.; Duffy, Kirsten P.; Provenza, Andrew J.

    2011-01-01

    Excessive vibration of turbomachinery blades causes high cycle fatigue problems which require damping treatments to mitigate vibration levels. One method is the use of piezoelectric materials as passive or active dampers. Based on the technical challenges and requirements learned from previous turbomachinery rotor blades research, an effort has been made to investigate the effectiveness of a shunted piezoelectric for the turbomachinery rotor blades vibration control, specifically for a condition with centrifugal rotation. While ample research has been performed on the use of a piezoelectric material with electric circuits to attempt to control the structural vibration damping, very little study has been done regarding rotational effects. The present study attempts to fill this void. Specifically, the objectives of this study are: (a) to create and analyze finite element models for harmonic forced response vibration analysis coupled with shunted piezoelectric circuits for engine blade operational conditions, (b) to validate the experimental test approaches with numerical results and vice versa, and (c) to establish a numerical modeling capability for vibration control using shunted piezoelectric circuits under rotation. Study has focused on a resonant damping control using shunted piezoelectric patches on plate specimens. Tests and analyses were performed for both non-spinning and spinning conditions. The finite element (FE) shunted piezoelectric circuit damping simulations were performed using the ANSYS Multiphysics code for the resistive and inductive circuit piezoelectric simulations of both conditions. The FE results showed a good correlation with experimental test results. Tests and analyses of shunted piezoelectric damping control, demonstrating with plate specimens, show a great potential to reduce blade vibrations under centrifugal loading.

  2. Pleuro-peritoneal shunting. Alternative therapy for pleural effusions.

    PubMed Central

    Little, A G; Kadowaki, M H; Ferguson, M K; Staszek, V M; Skinner, D B

    1988-01-01

    Pleural effusions are resistant to standard therapy, which causes discomfort and can require prolonged hospitalization. As an alternative, pleuroperitoneal shunting for pleural effusions of various etiologies was evaluated. We implanted 36 shunts in 29 patients. Two patients had bilateral shunts and five had shunt revisions. The effusion was related to a malignancy in 22 patients, postoperative chylothorax in two patients, and other causes in five patients. Therapeutic thoracentesis had been attempted in 28 patients, and eight had had chest tube placement previously with attempted sclerosis. Seven patients had a trapped lung syndrome. There was no operative mortality. All patients were deemed ready for discharge from the hospital if they had recovered from the operation within 48 hours. Five patients had poor results, either because of a moribund status or their refusal or inability to pump the shunt. Of the remaining 24 patients, four had good results with temporary improvement, and excellent results were achieved in 20 patients (83.3%), who experienced symptomatic relief and stabilization or regression of pleural effusion until the time of their death. Patients with chylothorax experienced complete resolution. The 14 patients with malignant effusions had a median survival of 4 months, and there were no instances of peritoneal tumor seeding. In conclusion, pleuroperitoneal shunting is an alternative therapy for pleural effusions that requires a limited hospitalization only, is associated with minimal and short-term discomfort, achieves excellent results in properly selected patients, and is the only viable therapy when lung expansion cannot be achieved. Images Fig. 1. Figs. 3A-C. Figs. 3A-C. Figs. 4A and B. Figs. 5A-C. Figs. 5A-C. Figs. 6A-C. Figs. 6A-C. PMID:3178332

  3. Utility of Operative Glaucoma Tube Shunt Viscoelastic Bolus Flush

    PubMed Central

    Groth, Sylvia L; Greider, Kelsi L

    2015-01-01

    ABSTRACT Objective: To assess the utility of viscoelastic injection to induce bleb expansion and decrease intraocular pressure (IOP) in eyes with encapsulated glaucoma tube shunt blebs. Design: Case series. Subjects and participants: Forty-three glaucomatous eyes, including 13 eyes with congenital, 13 uveitic, 5 neovascular, 5 open angle, 4 narrow angle and 3 traumatic glaucomas. Methods, interventions or testing: All patients underwent viscoelastic flush procedure. A pre-bent 27 or 30-gauge cannula was passed through a 25-gauge paracentesis, advanced over the iris across the anterior chamber, and insinuated into the tube shunt lumen. Once the cannula was firmly lodged in position, 0.45 to 0.85 ml of viscoelastic was injected to hyperinflate the bleb. Main outcome measures: Paired t-tests were performed comparing preoperative IOP and number of medications used preoperatively vs levels measured at 1, 6, 12, 18 and 24 months. Results: Intraocular pressure was reduced from a mean preoperative level of 26.0 ± 1.2 (sem) mm Hg to 15.8 ± 1.0 at 1 month, remaining stable thereafter at each 6-month interval with 15.1 ± 1.1 mm Hg at 24 months (p < 0.0001). Medication use did not vary significantly from baseline. Pressure remained < 21 mm Hg after 2 years in 85% of eyes cannulated within 1 year of primary tube shunt implantation (n = 23), and in 62% of eyes cannulated more than 1 year after tube shunt placement (n = 20). Conclusion: Tube shunt expansion with bolus viscoelastic flush successfully restored encapsulated bleb function, providing a substantial (~10 mm Hg) IOP decrease into the mid-normal pressure range. This persisted in the majority of treated eyes for the entire study period. How to cite this article: Groth SL, Greider KL, Sponsel WE. Utility of Operative Glaucoma Tube Shunt Viscoelastic Bolus Flush. J Curr Glaucoma Pract 2015;9(3):73-76. PMID:26997840

  4. Rare sequelae following ventriculoatrial shunt: Case report and review of literature

    PubMed Central

    Gopal, Vinu Venu; Peethambaran, Anil Kumar

    2016-01-01

    Ventriculoatrial shunt (VA) is one of the oldest solutions for hydrocephalus. However over subsequent years various complication of VA shunt such as obstructions, malposition, shunt infections, cardiac complications such as endocarditis, traumatic perforation, heart failure, tricuspid regurgitation, intraatrial thrombus, and pulmonary hypertension are reported. Hence, VA shunt procedure has fallen into disrepute. Still VA shunt may be a good option in selected patients with hostile peritoneum. Newer placement strategies and monitoring methods have been put forward to reduce complication following VA shunt. In this case report, we share a rare case of endocarditis with tricuspid regurgitation following a migrated retained calcified shunt tube in the right ventricle of heart 30 years after of VA shunt that was successfully managed. PMID:27057231

  5. Rare sequelae following ventriculoatrial shunt: Case report and review of literature.

    PubMed

    Gopal, Vinu Venu; Peethambaran, Anil Kumar

    2016-01-01

    Ventriculoatrial shunt (VA) is one of the oldest solutions for hydrocephalus. However over subsequent years various complication of VA shunt such as obstructions, malposition, shunt infections, cardiac complications such as endocarditis, traumatic perforation, heart failure, tricuspid regurgitation, intraatrial thrombus, and pulmonary hypertension are reported. Hence, VA shunt procedure has fallen into disrepute. Still VA shunt may be a good option in selected patients with hostile peritoneum. Newer placement strategies and monitoring methods have been put forward to reduce complication following VA shunt. In this case report, we share a rare case of endocarditis with tricuspid regurgitation following a migrated retained calcified shunt tube in the right ventricle of heart 30 years after of VA shunt that was successfully managed. PMID:27057231

  6. Endophthalmitis associated with Glaucoma Shunt Intraluminal Stent Exposure

    PubMed Central

    Kerr, Nathan M; Ruddle, Jonathan B; Ang, Ghee Soon

    2016-01-01

    ABSTRACT Endophthalmitis post glaucoma drainage implant (GDI) surgery is rare, often associated with tube or plate exposure. We report a case of endophthalmitis following glaucoma shunt intraluminal stent exposure in a patient who underwent Baerveldt glaucoma implant surgery. Endophthalmitis following manipulation of intraluminal stents is a rare complication of GDIs but potentially vision threatening condition that needs to be carefully screened for and treated immediately. How to cite this article: Kwon HJ, Kerr NM, Ruddle JB, Ang GS. Endophthalmitis associated with Glaucoma Shunt Intraluminal Stent Exposure. J Curr Glaucoma Pract 2016;10(1):36-37. PMID:27231417

  7. Modeling, analysis and verification of a partial shunt system

    SciTech Connect

    Lee, J.R.

    1996-12-31

    Spacecraft power system modeling, analysis and verification techniques using the electronic circuit simulation programs such as SPICE and SABER are presented. Partial shunt control system dynamics including the loop gain and bus impedance are derived. A typical partial shunt system is modeled and the loop gain of the system is simulated using an electronic circuit simulator. To confirm the circuit model simulation results prior to expensive hardware testing, they should be compared with the results simulated from a transfer function model derived from circuit equations. The spacecraft test results finally verify the modeling and analysis.

  8. Development of pseudointima and stenosis after transjugular intrahepatic portasystemic shunts: characterization of cell phenotype and function.

    PubMed

    Sanyal, A J; Contos, M J; Yager, D; Zhu, Y N; Willey, A; Graham, M F

    1998-07-01

    The clinical utility of transjugular intrahepatic portasystemic shunts (TIPS) is frequently complicated by the ingrowth of tissue into the stent lumen, causing stent stenosis. These studies were undertaken to define the cellular and matrix components of the pseudointima, define the phenotype and function of the mesenchymal cells in the pseudointima and maintain them in culture, and to study the differences between stenotic and nonstenosed stents. A total of 35 stents were evaluated. TIPS pseudointima were examined histologically, by immunohistochemistry and in situ hybridization to determine the cellular and connective tissue constituents. Mesenchymal cells were grown from tissue within the TIPS and around it, and their phenotype was studied and compared with control smooth muscle cells and fibroblasts. Masson's trichrome staining of histological sections demonstrated that TIPS tissue was composed of collagen and palisades of mesenchymal cells and was lined by an endothelium. Immunostaining demonstrated strong and uniform alpha-smooth muscle staining in TIPS mesenchymal cells and peri-TIPS cells. Type I procollagen mRNA expression was demonstrated in mesenchymal cells in and around the stent by in situ hybridization. TIPS mesenchymal cells secreted less radiolabeled fibronectin, and far more type III, relative to type I, collagen compared with peri-TIPS cells. TIPS cells also expressed high levels of type III procollagen mRNA compared with peri-TIPS cells. There was no difference between stenotic stents and nonstenosed stents with respect to clinical features, time from stenting, gross morphology, histology, presence of bile fistulae, and cell phenotype. However, smooth muscle cells (SMC) from stenotic stents demonstrated both greater cell proliferation and collagen I and III secretion compared with those from nonstenosed stents. These data demonstrate that TIPS stenosis results from an accumulation of collagen and proliferation of SMC within the stent lumen. PMID

  9. Early onset tension pneumocephalus following ventriculoperitoneal shunt insertion for normal pressure hydrocephalus: a case report.

    PubMed

    Barada, Wissam; Najjar, Marwan; Beydoun, Ahmad

    2009-04-01

    The occurrence of tension pneumocephalus following ventriculoperitoneal (v.p.) shunt insertion is extremely rare, and is usually of delayed onset. We report a patient who developed an acute subdural tension pneumocephalus within 1 day following placement of a v.p. shunt for normal pressure hydrocephalus as a complication from shunt surgery. PMID:19185417

  10. Successful Embolization of a Spontaneous Mesocaval Shunt Using the Amplatzer Vascular Plug II

    SciTech Connect

    Boixadera, Helena; Tomasello, Alejandro; Quiroga, Sergi; Cordoba, Joan; Perez, Mercedes; Segarra, Antoni

    2010-10-15

    A 48-year-old man with alcoholic liver cirrhosis and hepatic encephalopathy was found to have a large, spontaneous mesocaval shunt. The shunt was successfully occluded with the use of an Amplatzer Vascular Plug. To our knowledge, this is the first report of the use of this device to embolize a mesocaval shunt involving the superior mesenteric vein.

  11. High-Flow Arterio-Hepatic Venous Shunt in Hepatocellular Carcinoma: Use of Multi-Electrode Radiofrequency for Shunt Obliteration

    SciTech Connect

    Pua, Uei

    2015-10-15

    Intra-tumoral arterio-hepatic venous shunting (AHVS) poses an impediment to transarterial chemoembolization of liver tumors. Not only does it present a potential hazard for systemic shunting and embolization, but also the altered flow dynamics may also result in poor delivery of drug/embolics to the target tumor bed. Current available techniques to overcome AVHS include arterial embolization (particles, coils, glue, etc.) or temporary venous occlusion using balloons. We hereby illustrate the use of radiofrequency ablation to obliterate a complex AHVS consisting of a varix-like venous aneurysm.

  12. Appearance Normalization of Histology Slides

    PubMed Central

    Niethammer, Marc; Borland, David; Marron, J. S.; Woosley, John; Thomas, Nancy E.

    2011-01-01

    This paper presents a method for automatic color and intensity normalization of digitized histology slides stained with two different agents. In comparison to previous approaches, prior information on the stain vectors is used in the estimation process, resulting in improved stability of the estimates. Due to the prevalence of hematoxylin and eosin staining for histology slides, the proposed method has significant practical utility. In particular, it can be used as a first step to standardize appearances across slides, that is very effective at countering effects due to differing stain amounts and protocols, and to slide fading. The approach is validated using synthetic experiments and 13 real datasets. PMID:25360444

  13. Comparison of passive inductor designs for piezoelectric shunt damping

    NASA Astrophysics Data System (ADS)

    Lossouarn, Boris; Thierry, Olivier; Aucejo, Mathieu; Deü, Jean-François

    2016-04-01

    Considering piezoelectric damping, a resonant shunt can lead to a significant vibration reduction when tuned to the mechanical mode to control. However, limits appear when looking at practical applications in a low frequency range: the required inductance is often too high to be satisfied with standard passive components. Moreover, even if the inductor is eventually available, the internal resistance of the component generally exceeds the value which is required for a shunt optimization. Suitable inductors can be designed for applications requiring high inductance and low resistance values. Indeed, the permeance of a magnetic circuit can be significantly increased by the use of closed cores made of high permeability materials. In this paper, three designs are described and compared: an inductor from standard series and two handmade inductors involving a ferrite core and a nanocrystalline toroid. The components are successively integrated into a piezoelectric shunt dedicated to the vibration control of a cantilever beam. Depending on the frequency of the target mechanical mode to control, the benefits and the limits of the different inductors are observed. It is shown that custom designs can definitely extend to lower frequency the application of the passive resonant shunt strategy.

  14. Synchrony with shunting inhibition in a feedforward inhibitory network

    PubMed Central

    Hwang, Dong-Uk; Carney, Paul R.; Ditto, William L.

    2010-01-01

    Recent experiments have shown that GABAA receptor mediated inhibition in adult hippocampus is shunting rather than hyperpolarizing. Simulation studies of realistic interneuron networks with strong shunting inhibition have been demonstrated to exhibit robust gamma band (20–80 Hz) synchrony in the presence of heterogeneity in the intrinsic firing rates of individual neurons in the network. In order to begin to understand how shunting can contribute to network synchrony in the presence of heterogeneity, we develop a general theoretical framework using spike time response curves (STRC's) to study patterns of synchrony in a simple network of two unidirectionally coupled interneurons (UCI network) interacting through a shunting synapse in the presence of heterogeneity. We derive an approximate discrete map to analyze the dynamics of synchronous states in the UCI network by taking into account the nonlinear contributions of the higher order STRC terms. We show how the approximate discrete map can be used to successfully predict the domain of synchronous 1:1 phase locked state in the UCI network. The discrete map also allows us to determine the conditions under which the two interneurons can exhibit in-phase synchrony. We conclude by demonstrating how the information from the study of the discrete map for the dynamics of the UCI network can give us valuable insight into the degree of synchrony in a larger feedforward network of heterogeneous interneurons. PMID:20135213

  15. Peritoneo-vulvar catheter extrusion after shunt operation.

    PubMed

    Nagulic, M; Djordjevic, M; Samardzic, M

    1996-04-01

    We report an unusual case of catheter extrusion through the external genitalia. between the labium majus and the labium minus, in a 6-month-old hydrocephalic baby. The event occurred 5 months after placement of a ventriculoperitoneal shunt. PMID:8739410

  16. CONTEXT VIEW ALONG EXISTING PERIMETER TRACKS LOOKING TOWARDS SHUNTS IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CONTEXT VIEW ALONG EXISTING PERIMETER TRACKS LOOKING TOWARDS SHUNTS IN THEIR PRESENT-DAY POSITIONS, STORAGE SHED, AND MACHINE SHOP. LOOKING NORTHEAST. - Pennsylvania Railway Ore Dock, Lake Erie at Whiskey Island, approximately 1.5 miles west of Public Square, Cleveland, Cuyahoga County, OH

  17. Risk factors for shunt malfunction in pediatric hydrocephalus: a multicenter prospective cohort study.

    PubMed

    Riva-Cambrin, Jay; Kestle, John R W; Holubkov, Richard; Butler, Jerry; Kulkarni, Abhaya V; Drake, James; Whitehead, William E; Wellons, John C; Shannon, Chevis N; Tamber, Mandeep S; Limbrick, David D; Rozzelle, Curtis; Browd, Samuel R; Simon, Tamara D

    2016-04-01

    OBJECT The rate of CSF shunt failure remains unacceptably high. The Hydrocephalus Clinical Research Network (HCRN) conducted a comprehensive prospective observational study of hydrocephalus management, the aim of which was to isolate specific risk factors for shunt failure. METHODS The study followed all first-time shunt insertions in children younger than 19 years at 6 HCRN centers. The HCRN Investigator Committee selected, a priori, 21 variables to be examined, including clinical, radiographic, and shunt design variables. Shunt failure was defined as shunt revision, subsequent endoscopic third ventriculostomy, or shunt infection. Important a priori-defined risk factors as well as those significant in univariate analyses were then tested for independence using multivariate Cox proportional hazard modeling. RESULTS A total of 1036 children underwent initial CSF shunt placement between April 2008 and December 2011. Of these, 344 patients experienced shunt failure, including 265 malfunctions and 79 infections. The mean and median length of follow-up for the entire cohort was 400 days and 264 days, respectively. The Cox model found that age younger than 6 months at first shunt placement (HR 1.6 [95% CI 1.1-2.1]), a cardiac comorbidity (HR 1.4 [95% CI 1.0-2.1]), and endoscopic placement (HR 1.9 [95% CI 1.2-2.9]) were independently associated with reduced shunt survival. The following had no independent associations with shunt survival: etiology, payer, center, valve design, valve programmability, the use of ultrasound or stereotactic guidance, and surgeon experience and volume. CONCLUSIONS This is the largest prospective study reported on children with CSF shunts for hydrocephalus. It confirms that a young age and the use of the endoscope are risk factors for first shunt failure and that valve type has no impact. A new risk factor-an existing cardiac comorbidity-was also associated with shunt failure. PMID:26636251

  18. TIPS Versus Peritoneovenous Shunt in the Treatment of Medically Intractable Ascites

    PubMed Central

    Rosemurgy, Alexander S.; Zervos, Emmanuel E.; Clark, Whalen C.; Thometz, Donald P.; Black, Thomas J.; Zwiebel, Bruce R.; Kudryk, Bruce T.; Grundy, L Shane; Carey, Larry C.

    2004-01-01

    Objective: We undertook a prospective randomized clinical trial comparing TIPS to peritoneovenous (PV) shunts in the treatment of medically intractable ascites to establish relative efficacy and morbidity, and thereby superiority, between these shunts. Methods: Thirty-two patients were prospectively randomized to undergo TIPS or peritoneovenous (Denver) shunts. All patients had failed medical therapy. Results: After TIPS versus peritoneovenous shunts, median (mean ± SD) duration of shunt patency was similar: 4.4 months (6 ± 6.6 months) versus 4.0 months (5 ± 4.6 months). Assisted shunt patency was longer after TIPS: 31.1 months (41 ± 25.9 months) versus 13.1 months (19 ± 17.3 months) (P < 0.01, Wilcoxon test). Ultimately, after TIPS 19% of patients had irreversible shunt occlusion versus 38% of patients after peritoneovenous shunts. Survival after TIPS was 28.7 months (41 ± 28.7 months) versus 16.1 months (28 ± 29.7 months) after peritoneovenous shunts. Control of ascites was achieved sooner after peritoneovenous shunts than after TIPS (73% vs. 46% after 1 month), but longer-term efficacy favored TIPS (eg, 85% vs. 40% at 3 years). Conclusion: TIPS and peritoneovenous shunts treat medically intractable ascites. Absence of ascites after either is uncommon. PV shunts control ascites sooner, although TIPS provides better long-term efficacy. After either shunt, numerous interventions are required to assist patency. Assisted shunt patency is better after TIPS. Treating medically refractory ascites with TIPS risks early shunt-related mortality for prospects of longer survival with ascites control. This study promotes the application of TIPS for medically intractable ascites if patients undergoing TIPS have prospects beyond short-term survival. PMID:15166968

  19. Effect of peritoneo-venous shunt on portal pressure.

    PubMed Central

    Samanta, A K; Leevy, C M

    1989-01-01

    The cause of variceal bleed after a peritoneo-venous shunt is not known. Portal haemodynamic consequences of a peritoneo-venous shunt are poorly understood. The most critical period after a peritoneo-venous shunt is the early postoperative period when rapid mobilisation of peritoneal fluid occurs. Serial changes in the portal pressure during the early postoperative period have not been recorded. In the present study preoperative wedge hepatic vein (WHV), right atrial (RA) and pulmonary capillary wedged (PCW) pressures, cardiac index (CI), and plasma volume (PV) were measured in five alcoholic cirrhotic patients with tense ascites for up to 20 hours postoperatively. The longterm effect was assessed by repeating the intrahepatic and/or wedged hepatic vein pressures in three of the surviving patients after 10 to 20 months. A significant increase in the circulatory dynamics and portal pressure was seen within two hours after shunt placement. Wedged hepatic vein pressure increased from 27.6 (8.2) mmHg to 37.2 (9.2) mmHg (p less than 0.01), RA pressure increased from 6.8 (1.5) mmHg to 14.0 (4.3) mmHg (p less than 0.05), PCW increased from 7.2 (3.5) mmHg to 19.3 (5.7) mmHg (p less than 0.01), CI increased from 3.4 (0.27) lit/m2/min to 4.3 (0.85) lit/m2/min (p less than 0.05). This was accompanied by a 34% increase in the plasma volume from 1838.5 (142.1) to 2471.4 (210) ml/m2. These derangements were maintained up to 20 hours postoperatively. After 10 to 20 months, repeat measurements revealed a return to preoperative measurements. It is concluded that there is an acute increase portal pressure after a peritoneo-venous shunt attributed to increased circulation plasma volume, resulting from rapid mobilisation of ascitic fluid after the shunt. A sudden increase in portal pressure might be an important provoking factor for variceal bleeding after peritoneo-venus shunt. PMID:2920931

  20. Control of an electromechanical hydrocephalus shunt--a new approach.

    PubMed

    Elixmann, Inga M; Kwiecien, Monika; Goffin, Christine; Walter, Marian; Misgeld, Berno; Kiefer, Michael; Steudel, Wolf-Ingo; Radermacher, Klaus; Leonhardt, Steffen

    2014-09-01

    Hydrocephalus is characterized by an excessive accumulation of cerebrospinal fluid (CSF). Therapeutically, an artificial pressure relief valve (so-called shunt) is implanted which opens in case of increased intracranial pressure (ICP) and drains CSF into another body compartment. Today, available shunts are of a mechanical nature and drainage depends on the pressure drop across the shunt. According to the latest data, craniospinal compliance is considered to be even more important than mean ICP alone. In addition, ICP is not constant but varies due to several influences. In fact, heartbeat-related ICP waveform patterns depend on volume changes in the cranial vessels during a heartbeat and changes its shape as a function of craniospinal compliance. In this paper, we present an electromechanical shunt approach, which changes the CSF drainage as a function of the current ICP waveform. A series of 12 infusion tests in patients were analyzed and revealed a trend between the compliance and specific features of the ICP waveform. For waveform analysis of patient data, an existing signal processing algorithm was improved (using a Moore machine) and was implemented on a low-power microcontroller within the electromechanical shunt. In a test rig, the ICP waveforms were replicated and the decisions of the ICP analysis algorithm were verified. The proposed control algorithm consists of a cascaded integral controller which determines the target ICP from the measured waveform, and a faster inner-loop integral controller that keeps ICP close to the target pressure. Feedforward control using measurement data of the patient's position was implemented to compensate for changes in hydrostatic pressure during change in position. A model-based design procedure was used to lay out controller parameters in a simple model of the cerebrospinal system. Successful simulation results have been obtained with this new approach by keeping ICP within the target range for a healthy waveform. PMID

  1. Histological findings in human brucellosis

    PubMed Central

    Hunt, A. C.; Bothwell, P. W.

    1967-01-01

    The histological findings in 14 cases of brucellosis are described. Unusual findings include the occurrence of brucellosis in a patient with Hodgkin's disease and in another with lymphosarcoma. A patient with hepatic cirrhosis apparently due to brucellosis is included in the series. Images PMID:5632572

  2. Strongyloidiasis histologically mimicking eosinophilic folliculitis.

    PubMed

    Cannavò, Serafinella P; Guarneri, Fabrizio; Guarneri, Claudio

    2004-01-01

    The authors report an unusual case of strongyloidiasis in an Italian patient, who has always lived in Sicily. The patient presented with marked blood eosinophilia and an itching maculo-papular eruption, histologically simulating eosinophilic folliculitis. The clinical resolution was achieved after albendazol therapy. PMID:15319162

  3. Histological evolution of pleuroparenchymal fibroelastosis

    PubMed Central

    Hirota, Takako; Yoshida, Yuji; Kitasato, Yasuhiko; Yoshimi, Michihiro; Koga, Takaomi; Tsuruta, Nobuko; Minami, Masato; Harada, Taishi; Ishii, Hiroshi; Fujita, Masaki; Nabeshima, Kazuki; Nagata, Nobuhiko; Watanabe, Kentaro

    2015-01-01

    Aims To investigate the histological evolution in the development of pleuroparenchymal fibroelastosis (PPFE). Methods and results We examined four patients who had undergone surgical lung biopsy twice, or who had undergone surgical lung biopsy and had been autopsied, and in whom the histological diagnosis of the first biopsy was not PPFE, but the diagnosis of the second biopsy or of the autopsy was PPFE. The histological patterns of the first biopsy were cellular and fibrotic interstitial pneumonia, cellular interstitial pneumonia (CIP) with organizing pneumonia, CIP with granulomas and acute lung injury in cases 1, 2, 3, and 4, respectively. Septal elastosis was already present in the non-specific interstitial pneumonia-like histology of case 1, but a few additional years were necessary to reach consolidated subpleural fibroelastosis. In case 3, subpleural fibroelastosis was already present in the first biopsy, but only to a small extent. Twelve years later, it was replaced by a long band of fibroelastosis. The septal inflammation and fibrosis and airspace organization observed in the first biopsies were replaced by less cellular subpleural fibroelastosis within 3–12 years. Conclusions Interstitial inflammation or acute lung injury may be an initial step in the development of PPFE. PMID:25234959

  4. Histologic Technician. Laboratory Occupations Cluster.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for histologic technician is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a career ladder, a matrix relating duty/task numbers to job titles, and a task list. Each task…

  5. Reordering Histology to Enhance Engagement

    ERIC Educational Resources Information Center

    Amerongen, Helen

    2011-01-01

    In redesigning the preclinical curriculum and shifting from a discipline-based approach to an organ system-based approach, faculty at the University of Arizona College of Medicine in Tucson took the opportunity to restructure the sequence of introductory histology content to make it more engaging and relevant. In this article, the author describes…

  6. Fuzzy Inference System Approach for Locating Series, Shunt, and Simultaneous Series-Shunt Faults in Double Circuit Transmission Lines

    PubMed Central

    Swetapadma, Aleena; Yadav, Anamika

    2015-01-01

    Many schemes are reported for shunt fault location estimation, but fault location estimation of series or open conductor faults has not been dealt with so far. The existing numerical relays only detect the open conductor (series) fault and give the indication of the faulty phase(s), but they are unable to locate the series fault. The repair crew needs to patrol the complete line to find the location of series fault. In this paper fuzzy based fault detection/classification and location schemes in time domain are proposed for both series faults, shunt faults, and simultaneous series and shunt faults. The fault simulation studies and fault location algorithm have been developed using Matlab/Simulink. Synchronized phasors of voltage and current signals of both the ends of the line have been used as input to the proposed fuzzy based fault location scheme. Percentage of error in location of series fault is within 1% and shunt fault is 5% for all the tested fault cases. Validation of percentage of error in location estimation is done using Chi square test with both 1% and 5% level of significance. PMID:26413088

  7. New and improved ways to treat hydrocephalus: Pursuit of a smart shunt

    PubMed Central

    Lutz, Barry R.; Venkataraman, Pranav; Browd, Samuel R.

    2013-01-01

    The most common treatment for hydrocephalus is placement of a cerebrospinal fluid shunt to supplement or replace lost drainage capacity. Shunts are life-saving devices but are notorious for high failure rates, difficulty of diagnosing failure, and limited control options. Shunt designs have changed little since their introduction in 1950s, and the few changes introduced have had little to no impact on these long-standing problems. For decades, the community has envisioned a “smart shunt” that could provide advanced control, diagnostics, and communication based on implanted sensors, feedback control, and telemetry. The most emphasized contribution of smart shunts is the potential for advanced control algorithms, such as weaning from shunt dependency and personalized control. With sensor-based control comes the opportunity to provide data to the physician on patient condition and shunt function, perhaps even by a smart phone. An often ignored but highly valuable contribution would be designs that correct the high failure rates of existing shunts. Despite the long history and increasing development activity in the past decade, patients are yet to see a commercialized smart shunt. Most smart shunt development focuses on concepts or on isolated technical features, but successful smart shunt designs will be a balance between technical feasibility, economic viability, and acceptable regulatory risk. Here, we present the status of this effort and a framework for understanding the challenges and opportunities that will guide introduction of smart shunts into patient care. PMID:23653889

  8. Lumboatrial shunt in a patient with Crouzon syndrome complicated by pseudotumor cerebri.

    PubMed

    Sankey, Eric W; Khattab, Mohamed H; Elder, Benjamin D; Goodwin, C Rory; Rekate, Harold L; Rigamonti, Daniele

    2015-09-01

    A 25-year-old man with Crouzon syndrome complicated by pseudotumor cerebri and multiple shunt failures presented with progressive back and neck pain, intermittent headaches, and associated vomiting secondary to shunt infection. Due to his previous history of repeated failure of both ventriculoperitoneal and lumboperitoneal (LP) shunting procedures, the decision was made to place a lumboatrial (LA) shunt via an approach through the internal jugular vein. The procedure was uncomplicated and the man's symptoms were relieved. Despite significant improvement, the LA shunt limited his exercise tolerance, and as an avid runner and weight lifter, he requested reconversion back to an LP shunt. At a follow-up of 20months, he continued to do well both clinically and radiographically. This case report summarizes the successful placement and use of an LA shunt for the treatment of intracranial hypertension in the setting of Crouzon syndrome. PMID:26021731

  9. Appearance normalization of histology slides.

    PubMed

    Vicory, Jared; Couture, Heather D; Thomas, Nancy E; Borland, David; Marron, J S; Woosley, John; Niethammer, Marc

    2015-07-01

    This paper presents a method for automatic color and intensity normalization of digitized histology slides stained with two different agents. In comparison to previous approaches, prior information on the stain vectors is used in the plane estimation process, resulting in improved stability of the estimates. Due to the prevalence of hematoxylin and eosin staining for histology slides, the proposed method has significant practical utility. In particular, it can be used as a first step to standardize appearance across slides and is effective at countering effects due to differing stain amounts and protocols and counteracting slide fading. The approach is validated against non-prior plane-fitting using synthetic experiments and 13 real datasets. Results of application of the method to adjustment of faded slides are given, and the effectiveness of the method in aiding statistical classification is shown. PMID:25863518

  10. Cerebral venous thrombosis after ventriculoperitoneal shunting: a case report.

    PubMed

    Matsubara, Teppei; Ayuzawa, Satoshi; Aoki, Tsukasa; Ikeda, Go; Shiigai, Masanari; Matsumura, Akira

    2014-01-01

    Ventriculoperitoneal shunting (VPS) is a simple procedure, but there are several potential complications. We describe the first reported case of cerebral venous thrombosis (CVT) after VPS. A 69-year-old man suffering from normal pressure hydrocephalus underwent left VPS. Two months later he developed CVT and cerebral venous hemorrhage in the left frontal lobe. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed the thrombus formation just adjacent to the shunt tube. One possible cause is compression of the cortical vein after brain shift and/or tension of the cortical vein due to intracranial hypotension. A protein C deficiency was also detected. Surgeons should be aware that cerebral venous thrombosis can occur after VPS. PMID:24257484

  11. Maintenance of silastic–teflon shunts for intermittent haemodialysis

    PubMed Central

    McIntosh, C. S.; Petrie, J. C.; Macleod, M.

    1969-01-01

    The occurrence of infection in the tissues surrounding external arteriovenous shunts was studied and die important relationship of pyogenic infection to clotting was confirmed. The local application of fusidic add tulle and lanolin greatly reduced the occurrence of both infection and clotting and the need for cannula replacement. Urokinase used for declotting shunts when standard procedures had failed, restored blood flow whether dotting was related to infection or to local vascular factors. This treatment is not advised when clotting is associated with a local abscess, as it may make cannula replacement necessary. Severe local vascular factors, such as metastatic calcification, Raynaud's phenomenon, and venous stenosis, may lead to poor blood flow, so that despite clot lysis elective cannula replacement or the creation of a subcutaneous arteriovenous fistula is required. Imagesp718-a PMID:5354876

  12. Cerebral Venous Thrombosis after Ventriculoperitoneal Shunting: A Case Report

    PubMed Central

    MATSUBARA, Teppei; AYUZAWA, Satoshi; AOKI, Tsukasa; IKEDA, Go; SHIIGAI, Masanari; MATSUMURA, Akira

    2014-01-01

    Ventriculoperitoneal shunting (VPS) is a simple procedure, but there are several potential complications. We describe the first reported case of cerebral venous thrombosis (CVT) after VPS. A 69-year-old man suffering from normal pressure hydrocephalus underwent left VPS. Two months later he developed CVT and cerebral venous hemorrhage in the left frontal lobe. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed the thrombus formation just adjacent to the shunt tube. One possible cause is compression of the cortical vein after brain shift and/or tension of the cortical vein due to intracranial hypotension (IH). A protein C deficiency was also detected. Surgeons should be aware that cerebral venous thrombosis can occur after VPS. PMID:24257484

  13. [Surgical treatment of refractory ascites with peritoneovenous shunt].

    PubMed

    Massari, R; Fulgente, R; Marinelli, S; Romessis, M

    1995-01-01

    Leveen and associates described a peritoneo-venous shunt which proved to be useful in patients with intractable ascites. Medical therapy, paracentesis and peritoneovenous shunt have been compared, but there is uncertainty about their relative merits. Therefore, the leveen device has be placed in last years in an increasing number of patients: it has not been shown by prospective trials to prolong survival significantly, although it may shorten hospitalization and improve the quality of life. A number of early and late complications were described but they do not influence the general results: origin and features of such complications are discussed as well as their prevention and treatment and personal cases are presented. Selection of patients and careful surgical procedure seems to be mandatory for better results. PMID:8706187

  14. Transient response of a static VAR shunt compensator

    SciTech Connect

    Best, R.A.; Zelaya-De La Parra, H.

    1996-05-01

    A typical static VAR shunt compensator has been analyzed so that the step response and steady-state errors can be identified. The results show that the steady-state error is dependent upon the error in the measurement of the currents` phase alone. They also show that an unstable condition can occur, though it should rarely arise in practice. All the theory was verified on a low power (240 V, 3 A) system.

  15. Biocompatibility of a novel tissue connector for fixation of tracheostoma valves and shunt valves.

    PubMed

    Geertsema, A A; Schutte, H K; van Leeuwen, M B; Rakhorst, G; Schakenraad, J M; van Luyn, M J; Verkerke, G J

    1999-11-01

    Rehabilitation after laryngectomy often includes the use of a shunt valve and a tracheostoma valve to restore voice. To improve the fixation method of these valves, a new tissue connector has been developed, basically consisting of a ring that will be integrated into surrounding tracheal soft tissue. The valves can be placed in the ring. To test the principle of the tissue connector, a prototype consisting of a subcutaneous polypropylene mesh and a percutaneous titanium stylus was implanted into the backskin of 10 rats by a two-stage surgical procedure. We reasoned that if a firm connection can be realized with the skin, a firm connection with the trachea will also be possible. The subcutaneous part was implanted first, followed by the percutaneous part after 6 weeks. The complete tissue connector with surrounding tissue was removed 8 weeks later and examined histologically. The principle of the new tissue connector proved to be effective: hardly any epithelial downgrowth appeared, and adhesion of soft tissue was demonstrated. No infection or severe inflammation reaction was detected. The tissue connector seems appropriate for its intended use. PMID:10535811

  16. Feasibility of externalized peritoneovenous shunt (EPVS) for malignant ascites

    PubMed Central

    2011-01-01

    Purpose To evaluate a new modified peritoneovenous shunt therapy, the externalized peritoneovenous shunt (EPVS) system placement, used to treat patients with malignant ascites. Methods We retrospectively reviewed 10 patients, who were not suited for conventional peritoneovenous shunts (PVS), with malignant ascites, which was refractory to medical therapies. Patient characteristics, technical success, efficacy, duration of EPVS placement, adverse events, and outcome were evaluated. Clinical efficacy of the EPVS was evaluated by the change in subjective symptoms. Results The primary reasons for applying EPVS were severe anasarca in 4 patients, potential PVS dysfunction in 3 patients, poor performance status in 2 patients, and a history of PVS occlusion in 1 patient. EPVS was successfully placed in all patients, and it provided clinical efficacy in 8 patients (80%). Early death occurred within 7 days after EPVS placement in 2 patients because of renal failure. The median duration of EPVS placement was 10.4 days (range, 2-28 days). In 6 patients (60%), the EPVS was exchanged to conventional PVS sequentially, since the initial EPVS placement resulted in an improvement of the subjective symptoms of the patients, without serious complications. Conclusion EPVS placement may be an option for patients with malignant ascites who may not be appropriate for conventional PVS placement. PMID:21777451

  17. Modified Blalock-Taussig Shunt with an Umbilical Vein Graft

    PubMed Central

    Leão, Luiz Eduardo V.; Andrade, José Carlos S.; Succi, José Ernesto; Cueva, Clotario C.; Ribeiro, Expedito E.; Carvalho, Antonio Carlos C.; Buffolo, Enio

    1985-01-01

    We describe a modification of the Blalock Taussig anastomosis, with the interposition of a glutaraldehyde-tanned umbilical vein graft between the subclavian and pulmonary arteries. This operation was performed in 64 children: 11 were less than 1 month of age (17.2%), and 23 were between 1 and 6 months of age (34.9%). Hospital deaths occurred in six patients—all less than 6 months of age (9.4%). There was no instance of shunt occlusion noted. The clinical course was uneventful among survivors, except for one patient who died of endocarditis in the late postoperative follow-up. The shunt procedure may be performed very rapidly, with minimal dissection, allowing the use of a graft larger than the diameter of the subclavian artery. This modification of the Blalock Taussig operation compares favorably with our previous experience with other shunt procedures and may be considered a valuable alternative in the palliative surgical treatment of several malformations with severe pulmonary oligemia. Images PMID:15227043

  18. Myomucosal shunt following total laryngectomy: a report of 31 cases.

    PubMed

    Brasnu, D; Strome, M; Ménard, M; Pfauwadel, M C; Martinez, P; Janot, F; Laccourreye, H

    1989-01-01

    An original technique of voice rehabilitation following total laryngectomy based on the concept of a myomuscosal unit was originally described by Strome. Thirty-one cases of myomucosal shunts (MMS) are analyzed in the present report. The 14 initial cases failed because of a lack clinical and surgical experience and insufficient selection of the patients. Among the last 17 cases, 1 was lost to follow-up, 1 had an insufficient follow-up, and 2 patients refused to speak with the MMS instead of a patent shunt; 5 of the remaining patients had voices evaluated as excellent, 7 had voices interpreted as good and only 1 patient had a voice evaluated as poor. Aspiration was not a problem. Eleven patients were found to stenose their shunt, but fistula were recalibrated successfully. The MMs can be used safely in oncological surgery and only 1 of 31 deaths in our total experience was due to a local recurrence. These findings show that the MMS is a reliable procedure for voice restoration following total laryngectomy; a prosthesis is not required and there are currently no oncological limits to the procedure. However, a very close follow-up of the patients is required after surgery. PMID:2686602

  19. Chronic Achilles paratenonitis in athletes: a histological and histochemical study.

    PubMed

    Kvist, M; Józsa, L; Järvinen, M J; Kvist, H

    1987-01-01

    Pathological alterations of chronic Achilles paratenonitis were studied histologically and histochemically in tissue samples obtained operatively from 16 athletes with this complaint and from 3 control patients. The activities of 11 different enzymes--lactate, succinate, malate, glucose-6-phosphate and glutamate dehydrogenases, lipoamide dehydrogenase and glutathione reductase (NADH2- and NADPH2-diaphorases), acid and alkaline phosphatases, phosphorylase and leucylaminopeptidase--were studied. Pathological findings were located diffusely around the tendon. A slight inflammatory cell reaction was found in all cases. The fatty areolar tissue was clearly thickened and edematous, and showed fibrinous exudations, widespread fat necrosis, considerable connective tissue proliferation and adhesion formation. The blood vessels showed profound degenerative and necrotizing changes. The thin membranes of the paratenon were clearly hypertrophied. Increased enzyme activities were mainly found in the fibroblasts, inflammatory cells and vascular walls. A moderate activity of lysosomal enzymes, an increased activity of enzymes of electron transport, anaerobic glycolysis, pentose phosphate shunt and decreased activity of those of aerobic energy metabolism were found. Simultaneously an increased amount of both neutral and acid mucopolysaccharides and a locally increased amount of elastic fibres were found in the inflamed paratenon. These results indicate that marked metabolic changes occur in paratenonitis, i.e. an increased catabolism and decreased oxygenation of the inflamed areas. The morphological alterations suggest that the gliding function of the paratenon may be impaired. PMID:3588019

  20. Depiction of ventriculoperitoneal shunt obstruction with single-photon emission computed tomography/computed tomography

    PubMed Central

    Aksoy, Sabire Yılmaz; Vatankulu, Betül; Uslu, Lebriz; Halac, Metin

    2016-01-01

    An 83-year-old male patient with ventriculoperitoneal shunt underwent radionuclide shunt study using single-photon emission computed tomography/computed tomography (SPECT/CT) to evaluate the shunt patency. The planar images showed activity at the cranial region and spinal canal but no significant activity at the peritoneal cavity. However, SPECT/CT images clearly demonstrated accumulation of activity at the superior part of bifurcation level with no activity at the distal end of shunt as well as no spilling of radiotracer into the peritoneal cavity indicating shunt obstruction. SPECT/CT makes the interpretation of radionuclide shunt study more accurate and easier as compared with traditional planar images. PMID:27385906

  1. Development of chronic hepatocerebral degeneration eight years after a distal splenorenal (Warren) shunt.

    PubMed Central

    Bleasel, A F; Waugh, R C; McCaughan, G W

    1989-01-01

    It is well known that chronic encephalopathy may be a major complication after the establishment of a surgical portal caval shunt for an episode of variceal haemorrhage. In an effort to minimise this problem Warren and colleagues developed the distal splenorenal shunt where the portal and mesenteric blood flow to the liver was left intact. It is now recognised, however, that the longterm incidence of encephalopathy may be no different with this type of shunt compared with conventional surgical portal systemic shunts. Acquired chronic hepatocerebral degeneration has not been reported after such a selective shunt. A patient with primary biliary cirrhosis is reported who developed the clinical features of this syndrome eight years after a successful distal splenorenal shunt. Images Fig. 1 Fig. 2 PMID:2583570

  2. Ventriculoatrial shunt catheter displacement in a child with partial anomalous pulmonary venous return: case report.

    PubMed

    Elhammady, Mohamed Samy A; Benglis, David M; Bhatia, Sanjiv; Sandberg, David I; Ragheb, John

    2008-07-01

    Ventriculoatrial (VA) shunts remain the most used alternative to ventriculoperitoneal shunts in infants with hydrocephalus. The authors report a case of an acute VA shunt malfunction as a result of distal catheter displacement in an 18-month-old girl with partial anomalous pulmonary venous return. The child presented with respiratory compromise, and a chest radiograph revealed a lung infiltrate and normal position of the distal shunt catheter tip. Computed tomography demonstrated stable ventricle size in comparison with previous studies. As the patient's respiratory distress progressed, she required intubation, mechanical ventilation with high airway pressures and inspired oxygen concentrations, muscle relaxants, and sedation. A routine morning chest radiograph several days after admission revealed displacement of the distal catheter into the left innominate vein. Later that day the child's pupils were noted to be large and unreactive and a distal shunt malfunction was diagnosed. Complications of VA shunts and the presumed mechanism by which the catheter became displaced are discussed. PMID:18590399

  3. A multi-stack simulation of shunt currents in vanadium redox flow batteries

    NASA Astrophysics Data System (ADS)

    Wandschneider, F. T.; Röhm, S.; Fischer, P.; Pinkwart, K.; Tübke, J.; Nirschl, H.

    2014-09-01

    A model for the shunt currents in an all-vanadium redox flow battery consisting of 3 stacks which are electrically connected in series. It is based on an equivalent circuit which treats the shunt current pathways as Ohmic resistors. The conductivity of the vanadium electrolyte has been measured for different state-of-charges in order to implement a dependency of the resistances on the state-of-charge of the system. Published results are used to validate the simulation data of a single stack. Three setups of pipe networks are evaluated using the model. The pipe connections between the stacks give rise to external shunt currents, which also increase the amount of shunt currents within the stacks. These connections also lead to a nonuniform distribution of the shunt currents. The effects of the shunt currents on the Coulombic efficiency and the energy efficiency of the system are studied by the means of the model.

  4. Thoracic complications of ventriculoperitoneal shunts: case report and review of the literature.

    PubMed

    Taub, E; Lavyne, M H

    1994-01-01

    Thoracic complications of ventriculoperitoneal shunts are rare, but potentially serious. The authors report a case of a drainage of cerebrospinal fluid into the tracheobronchial tree through a peritoneal shunt catheter that migrated into the chest. After injection of contrast material into the shunt, a plain radiograph of the chest revealed a bronchogram. The symptoms resolved after a revision of the shunt. Published case reports of this and other thoracic complications of ventriculoperitoneal shunts are comprehensively reviewed. A classification of such complications into three types is proposed as follows: intrathoracic trauma during placement of a shunt, migration of the peritoneal catheter into the chest (by either a supradiaphragmatic or a transdiaphragmatic route), and pleural effusion accompanying cerebrospinal fluid ascites. The possible mechanisms and contributing factors are discussed. PMID:8121558

  5. Chemoembolic Hepatopulmonary Shunt Reduction to Allow Safe Yttrium-90 Radioembolization Lobectomy of Hepatocellular Carcinoma

    SciTech Connect

    Gaba, Ron C.; VanMiddlesworth, Kyle A.

    2012-12-15

    Yttrium-90 ({sup 90}Y) radioembolization represents an emerging transcatheter treatment option for the management of hepatocellular carcinoma (HCC). Elevation of the hepatopulmonary shunt fraction risks nontarget radiation to the lungs and may limit the use of {sup 90}Y therapy in patients with locally advanced disease with vascular invasion, who often demonstrate increased shunting. We present two cases in which patients with HCC and portal vein invasion resulting in elevated hepatopulmonary shunt fractions underwent chemoembolic shunt closure to allow safe {sup 90}Y radioembolization. Both patients demonstrated excellent tumor response and patient survival. On this basis, we propose a role for chemoembolic reduction of the lung shunt fraction before {sup 90}Y radioembolization in patients with extensive tumor-related hepatopulmonary shunting.

  6. Histological aspects of cervical ripening.

    PubMed

    Ichijo, M; Shimizu, T; Sasai, Y

    1976-02-01

    There is a close relationship between the rate of the uterine cervix opening during parturition and the presence or absence of a completely ripened cervix. In order to learn the basic pattern of the ripening of cervix, histological and histochemical studies were performed on the human uterine cervix during pregnancy. It was noted that the collagen bundles disintegrated into fine fibers and also underwent quantitative changes during the ripening process of the cervix. During pregnancy, the number of connective tissue cells was increased, but that of mast cells was decreased. Acid mucopolysaccharides in the cervical ground substance were found to increase in late pregnancy. PMID:136067

  7. Tension pneumocephalus complicating ventriculoperitoneal shunt for cerebrospinal fluid rhinorrhoea: case report.

    PubMed

    Ikeda, K; Nakano, M; Tani, E

    1978-04-01

    A case of spontaneous nontraumatic cerebrospinal fluid rhinorrhoea secondary to aqueductal stenosis is reported. The patient required direct repair of the fistula after the insertion of a ventriculoperitoneal shunt for aqueductal stenosis. We emphasise an unusual complication of tension pneumocephalus in a case where the shunt patency had been substantiated. Intracranial pressure fall due to the siphon effect in the ventriculoperitoneal shunt tubing in the erect position might be responsible for ingress of an excessive amount of air. PMID:650239

  8. Management for traumatic chronic subdural hematoma patients with well-controlled shunt system for hydrocephalus

    PubMed Central

    Yamada, Shoko Mitrrt; Tomia, Yusuke; Murakami, Hideki; Nakane, Makoto

    2015-01-01

    Key Clinical Message Traumatic CSDH enlarged in two cases with VP or LP shunt system although the shunt valve pressure was increased to 200 mmH2O. In surgery, the hematoma cavity pressure was found to be 130 and 140 mmH2O, suggesting that to raise the shunt valve pressure is not effective for decreasing CSDH volume. PMID:26273439

  9. Reversibility of intrapulmonary arteriovenous shunts in liver cirrhosis documented by serial radionuclide perfusion lung scans

    SciTech Connect

    Chen, N.S.; Barnett, C.A.; Farrer, P.A.

    1984-05-01

    Using serial perfusion lung scans, the opening up and closure of right-to-left intrapulmonary arteriovenous shunts has been documented over a period of several weeks in a patient with chronic alcoholic liver disease. The presence of the shunts correlates well with the severity of hypoxemia and the presence of nodular mottling on chest radiographs. The time course of these changes with clinical status suggests lability and the functional nature of these shunts.

  10. Breast Capsular Cerebrospinal Fluid Collection from Migration of a Ventriculoperitoneal Shunt Catheter

    PubMed Central

    Knaus, William J.; Kamali, Parisa; Chun, Yoon

    2016-01-01

    Summary: In this case report we have described an unusual complication of ventriculoperitoneal shunt migration into a breast implant capsule. The patient was appropriately diagnosed with computed tomographic imaging and successfully managed with shunt revision and cerebrospinal fluid aspiration. Given the high complication profile of ventriculoperitoneal shunt catheters, this case suggests an opportunity for improved perioperative communication between plastic surgeons and neurosurgeons in patients with breast implants. Coordination regarding the subcutaneous catheter tunneling may hopefully minimize the risk of this complication. PMID:27257570

  11. Histology of the first fish

    USGS Publications Warehouse

    Smith, M.P.; Sansom, I.J.; Repetski, J.E.

    1996-01-01

    THE first description of Anatolepis Bockelie & Fortey was from early Ordovician sediments of Ny Friesland, Spitsbergen1,2, but the genus is now known from many localities in North America and Greenland, ranging in age from the Late Cambrian period to the Early Ordovician3-6. Although initially interpreted as an agnathan fish2,3 that predated other representatives7, this has been widely disputed because the available histological data were unconvincing6,8-10 and the scales fell outside the known morphological range of other accepted early vertebrates9-11. Further doubt was cast upon the vertebrate affinity of Anatolepis when specimens from East Greenland were interpreted as the cuticular fragments of aglaspid arthropods6, although this interpretation has also been refuted12. Here we report on the morphology and histology of large collections of Anatolepis, and demonstrate the presence of dentine, a tissue unique to vertebrates, confirming that the taxon is both a vertebrate and the oldest known fish.

  12. Embolization of portal-systemic shunts in cirrhotic patients with chronic recurrent hepatic encephalopathy

    SciTech Connect

    Sakurabayashi, Shin; Sezai, Shuichi; Yamamoto, Yoshihiro; Hirano, Masanori; Oka, Hiroshi

    1997-03-15

    Purpose. To evaluate the efficacy of embolization of portal-systemic shunts in cirrhotic patients with chronic recurrent hepatic encephalopathy (CRHE). Methods. Seven cirrhotic patients with CRHE refractory to medical treatment (3 men and 4 women, mean age 66 years) were studied. Five patients had splenorenal shunts, 1 had a gastrorenal shunt, and 1 had an intrahepatic portal vein-hepatic vein shunt. Shunt embolization was performed using stainless steel coils, with a percutaneous transhepatic portal vein approach in 4 patients and a transrenal vein approach in 3 patients. Results. After embolization, the shunt disappeared in 4 patients on either ultrasound pulsed Doppler monitoring or portography. Complications observed in the 7 patients were fever, transient pleural effusion, ascites, and mild esophageal varices. For 3-6 months after embolization, the 4 patients whose shunts disappeared showed minimal or no reappearance of a shunt, and had no recurrence of encephalopathy. The serum ammonia levels decreased and electroencephalograms also improved. One of the 4 patients, who developed mild esophageal varices, required no treatment. Treatment was effective in 3 of the 4 patients (75%) who underwent embolization via a transhepatic portal vein. Conclusion. Transvascular embolization of shunts improved the outcome in 4 of 7 patients. The most effective embolization was achieved via the percutaneous transhepatic portal vein approach.

  13. Optimization of shunt placement for the Norwood surgery using multi-domain modeling.

    PubMed

    Moghadam, Mahdi Esmaily; Migliavacca, Francesco; Vignon-Clementel, Irene E; Hsia, Tain-Yen; Marsden, Alison L

    2012-05-01

    An idealized systemic-to-pulmonary shunt anatomy is parameterized and coupled to a closed loop, lumped parameter network (LPN) in a multidomain model of the Norwood surgical anatomy. The LPN approach is essential for obtaining information on global changes in cardiac output and oxygen delivery resulting from changes in local geometry and physiology. The LPN is fully coupled to a custom 3D finite element solver using a semi-implicit approach to model the heart and downstream circulation. This closed loop multidomain model is then integrated with a fully automated derivative-free optimization algorithm to obtain optimal shunt geometries with variable parameters of shunt diameter, anastomosis location, and angles. Three objective functions: (1) systemic; (2) coronary; and (3) combined systemic and coronary oxygen deliveries are maximized. Results show that a smaller shunt diameter with a distal shunt-brachiocephalic anastomosis is optimal for systemic oxygen delivery, whereas a more proximal anastomosis is optimal for coronary oxygen delivery and a shunt between these two anatomies is optimal for both systemic and coronary oxygen deliveries. Results are used to quantify the origin of blood flow going through the shunt and its relationship with shunt geometry. Results show that coronary artery flow is directly related to shunt position. PMID:22757490

  14. The role of persistent foramen ovale and other shunts in decompression illness.

    PubMed

    Wilmshurst, Peter T

    2015-06-01

    A persistent foramen ovale (PFO) and other types of right-to-left shunts are associated with neurological, cutaneous and cardiovascular decompression illness (DCI). A right-to-left shunt is particularly likely to be implicated in causation when these types of DCI occur after dives that are not provocative. It is believed that venous nitrogen bubbles that form after decompression pass through the shunt to circumvent the lung filter and invade systemic tissues supersaturated with nitrogen (or other inert gas) and as a result there is peripheral amplification of bubble emboli in those tissues. Approximately a quarter of the population have a PFO, but only a small proportion of the population with the largest right-to-left shunts are at high risk of shunt-mediated DCI. The increased risk of DCI in people with migraine with aura is because migraine with aura is also associated with right-to-left shunts and this increased risk of DCI appears to be confi ned to those with a large PFO or other large shunt. Various ultrasound techniques can be used to detect and assess the size of right-to-left shunts by imaging the appearance of bubble contrast in the systemic circulation after intravenous injection. In divers with a history of shunt-mediated DCI, methods to reduce the risk of recurrence include cessation of diving, modification of future dives to prevent venous bubble liberation and transcatheter closure of a PFO. PMID:26165532

  15. Combined phacoemulsification with ExPRESS shunt in angle closure glaucoma

    PubMed Central

    Rao, Aparna

    2015-01-01

    Summary A 60-year-old woman diagnosed with primary angle closure glaucoma with extensive peripheral anterior synechiae (PAS) and advanced glaucomatous optic neuropathy unresponsive to maximal medical treatment, underwent clear corneal phacoemulsification and ExPRESS (Alcon Inc, Fort Worth, TX) shunt surgery in the right eye with intraoperative placement tailored to avoid areas of PAS. Postoperatively her visual acuity in the right eye was 20/20 and intraocular pressure was 13 mm Hg with the shunt in place and functioning bleb at final follow-up. The ExPRESS shunt can be used in angle closure eyes with good outcomes after proper placement of the shunt.

  16. Gold shunt for refractory advanced low-tension glaucoma with spared central acuity

    PubMed Central

    Le, Ryan; Gupta, Neeru

    2016-01-01

    The aim of this study is to report a case of gold shunt surgery for uncontrolled, low-tension glaucoma with good central vision, after having a previously failed trabeculectomy and tube shunt surgeries. The patient was receiving maximum medical glaucoma therapy of four different types with intraocular pressure of 17 mm Hg prior to gold shunt surgery. Five years later, intraocular pressure is well controlled in the low teens without the need for ocular medications, and glaucoma is stable following gold shunt surgery. PMID:27051320

  17. Effects of flow patterns and hemodynamic force on vascular endothelium in the temporary arteriovenous shunt loop in rabbits.

    PubMed

    Tanaka, Yoshio; Koghure, Tetsukuni; Ueno, Masaki; Sugiyama, Hitoshi; Hamamoto, Yhusuke; Tamai, Motoki; Taguchi, Noriyuki; Sakamoto, Haruhiko

    2013-06-01

    The purpose of this study was to investigate whether there is a risk of thrombosis in the temporary arteriovenous shunt loop (TAVSL). The authors established a TAVSL model in the rabbit. Experimental groups were divided into non-heparin treated and heparin treated. The maximum blood flow volume, blood viscosity, and radius of curvature were measured, and the Reynolds number and the sheer stress were calculated. Computational fluid dynamics (CFD) was used to predict the flow pattern in the TAVSL, and these predicted data were compared with histological results. Early occlusion was noted in 70% (7/10) of the non-heparin-treated group and 22% (2/9) of the heparin-treated group. CFD analysis predicted a high shear stress at the arterial anastomosis region and the outer luminal surface of the curved section. The intimal structure at the luminal surface of the curved section was extensively lost histologically. In the patent group, severe stenosis of the lumen was noted at the apex of the loop due to an organized thrombus. Thus, thrombosis is likely to occur in the TAVSL due to endothelium injury caused by high shear stress, and this results in the formation of white thrombi at an early stage and an organized thrombus at a late stage. PMID:23568531

  18. Interatrial shunt flow profiles in newborn infants: a colour flow and pulsed Doppler echocardiographic study.

    PubMed Central

    Hiraishi, S; Agata, Y; Saito, K; Oguchi, K; Misawa, H; Fujino, N; Horiguchi, Y; Yashiro, K

    1991-01-01

    Interatrial shunt flow profiles in 36 normal term infants were examined serially by colour flow and pulsed Doppler echocardiographic techniques from within an hour of birth to four or five days after birth. Shunt flow across the foramen ovale was detected in 33 normal infants (92%) within an hour of birth (mean 40 minutes). The occurrence of interatrial shunting decreased with age, but a shunt signal was still detected in 17 infants (47%) on the fourth or fifth day of life, by then the ductus arteriosus had already closed in all the normal infants. The direction of interatrial shunt flow was predominantly left-to-right, but in 64% there was a coexistent small right-to-left shunt in diastole within an hour of birth; by four to five days it was found in 19%. In the six patients with persistent fetal circulation the direction of the interatrial shunt flow was predominantly right-to-left with biphasic peaks in diastole and systole at the early stage of the disease, and the period of right-to-left shunt flow during each cardiac cycle was significantly longer than that in normal infants examined within 1 hour of birth. In all patients the ductus closed before the foramen ovale. At the time of ductal closure in all patients with persistent fetal circulation right-to-left shunt flow was seen during diastole and its period was still prolonged. These findings suggest that interatrial shunting, predominantly left-to-right, is common in normal newborn infants. Evaluation of the characteristics of the interatrial shunt by Doppler echocardiography may be useful for predicting the progress of or improvement in neonates with persistent fetal circulation. Images PMID:1993129

  19. Shunting arc plasma source for pure carbon ion beam.

    PubMed

    Koguchi, H; Sakakita, H; Kiyama, S; Shimada, T; Sato, Y; Hirano, Y

    2012-02-01

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA∕mm(2) at the peak of the pulse. PMID:22380206

  20. A theoretical and experimental study of coplanar waveguide shunt stubs

    NASA Technical Reports Server (NTRS)

    Dib, Nihad I.; Ponchak, George E.; Katehi, Linda P. B.

    1993-01-01

    A comprehensive theoretical and experimental study of straight and bent coplanar waveguide (CPW) shunt stubs is presented. In the theoretical analysis, the CPW is assumed to be inside a cavity while, the experiments are performed on open structures. For the analysis of CPW discontinuities with air-bridges, a hybrid technique was developed which was validated through extensive theoretical and experimental comparisons. The effect of the cavity resonances on the behavior of the stubs with and without air-bridges is investigated. In addition, the encountered radiation loss due to the discontinuities is evaluated experimentally.

  1. Shunting arc plasma source for pure carbon ion beama)

    NASA Astrophysics Data System (ADS)

    Koguchi, H.; Sakakita, H.; Kiyama, S.; Shimada, T.; Sato, Y.; Hirano, Y.

    2012-02-01

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA/mm2 at the peak of the pulse.

  2. Perturbation theory for a resistivity shunted Josephson element

    NASA Technical Reports Server (NTRS)

    Thompson, E. D.

    1973-01-01

    We present a systematic perturbation theory, extendable in principle to all orders of magnitude, for the solution of the equations of motion of an ideal Josephson element shunted by a resistance and driven by a dc current source and a small time-dependent source. We present second-order results for the case in which the time dependence is that of a single sinusoid, and these results are compared with other numerical and analytical calculations. Near, but not on, the first constant voltage step where the perturbation theory appears divergent, the current-voltage characteristic is calculated by means of a nonperturbative adiabatic procedure. The impedance and responsivity agree with earlier results.

  3. [PERITONEAL VENOUS SHUNT IN THE TREATMENT OF MALIGNANTASCITIS: PRELIMINARY REPORT

    PubMed

    Brazzini, Augusto; Cantella, Raúl

    1998-01-01

    The present study, mentions the use of a valve for the drainage os ascitic fluid, better known as the peritoneo venous shunt, as a paliation treatment in terminal oncologic patients. It was performed in four patients with diseminated carcinomas, of diferent primary ethiology. These patients had a bad life quality, because when admitted in our Radiology suite, the clinical examination showed shortness of breathearly saciety, lethargy, and were found handiccapped to perform their habitual skills. This is a short and preliminar series, but it is an encouraging report, because, the quality of life, our goal, is improved. PMID:12209221

  4. Piezoelectric vibration damping using resonant shunt circuits: an exact solution

    NASA Astrophysics Data System (ADS)

    Soltani, P.; Kerschen, G.; Tondreau, G.; Deraemaeker, A.

    2014-12-01

    The objective of this paper is to propose an exact closed-form solution to the {{H}∞ } optimization of piezoelectric materials shunted with inductive-resistive passive electrical circuits. Realizing that Den Hartog's method which imposes fixed points of equal height in the receptance transfer function is approximate, the parameters of the piezoelectric tuned vibration absorber are calculated through the direct minimization of the maxima of the receptance. The method is applied to a one-degree-of-freedom primary oscillator considering various values of the electromechanical coupling coefficients.

  5. Transcatheter closure of modified Blalock-Taussig shunt with Gianturco-Grifka Vascular Occlusion Device.

    PubMed

    Hoyer, M H; Leon, R A; Fricker, F J

    1999-12-01

    A 15-year-old girl with previous repair of a complex cyanotic congenital heart defect had persistence of a modified left Blalock-Taussig shunt that could not be ligated at surgery. Six years later, antegrade delivery of a Gianturco-Grifka Vascular Occlusion Device resulted in complete closure of the shunt. Cathet. Cardiovasc. Intervent. 48:365-367, 1999. PMID:10559814

  6. Visual disturbance following shunt malfunction in a patient with congenital hydrocephalus.

    PubMed

    Oyama, Hirofumi; Hattori, Kenichi; Kito, Akira; Maki, Hideki; Noda, Tomoyuki; Wada, Kentaro

    2012-01-01

    A 25-year-old woman presented with complaints of nausea and headache. She had been treated with a ventriculoperitoneal shunt for hydrocephalus when she was 7 months old. Her bilateral optic discs showed moderate atrophy. Right visual acuity allowed only perception of hand movement and left visual acuity was 0.02 (1.2). Computed tomography (CT) showed mild ventricular dilation but no periventricular lucency. Intracranial pressure (ICP) was not high when the shunt valve was punctured. Her visual acuity deteriorated 5 days after the consultation. She was referred again 8 days after the first consultation. The bilateral optic discs were completely pale. Both pupils were dilated on admission, and the bilateral direct light reflexes were absent. The patient could slightly detect only green light stimulus. CT showed moderate enlargement of the ventricle. ICP was 47 cmH(2)O when the shunt valve was punctured. Shuntgraphy showed obstruction of the shunt at the distal end of peritoneal catheter. Emergent total shunt revision was performed. She could detect dark stimulus and the still-dilated left pupil had recovered direct light reflex on the next day. The visual acuity was 0.01 (0.7) on the left 6 months after the operation, although she was blind in the right eye and the bilateral optic discs were completely pale. Visual loss associated with shunt failure remains a major morbidity in shunted congenital hydrocephalus. Early diagnosis and shunt revision may allow visual recovery. PMID:23183081

  7. Role of the distal splenorenal shunt in management of variceal bleeding in Latin America.

    PubMed

    Orozco, H; Mercado, M A; Takahashi, T; García-Tsao, G; Guevara, L; Hernández Ortíz, J; Hernández-Cendejas, A; Tielve, M

    1990-07-01

    In the early 1970s, we began to perform selective shunts on a regular basis for the treatment of portal hypertension. In a 15-year period, 177 patients (155 with liver cirrhosis) were treated with 3 kinds of selective shunts: the Warren shunt (128 patients) the end-to-end splenorenal shunt (29 patients), and the splenocaval shunt (20 patients). One hundred sixty-seven of the procedures were elective. Operative mortality was 14%, and survival for the Child's class A group was 75% at 1 year, 69% at 5 years, and 65% at 15 years. Incapacitating encephalopathy was observed in 7% of the patients, rebleeding in 6%, and shunt thrombosis in 6%. Postoperative portal vein alterations included reduced venous diameter (13%) and thrombosis (21%). Experience with the Warren shunt in schistosomiasis, a disease in which normal liver function is the rule in Latin American countries, is discussed. We believe that, when feasible, the selective shunts are the treatment of choice for portal hypertension in Latin American countries. PMID:2368881

  8. Normal-pressure hydrocephalus: current understanding of diagnostic tests and shunting

    SciTech Connect

    Black, P.M.

    1982-02-01

    Normal-pressure hydrocephalus is no longer difficult to diagnose or treat-cranial computed tomographic scanning has made the diagnosis of ventricular enlargement straightforward, and shunt placement often helps the patient whose condition can be traced to a specific cause. Predicting accurately whether a patient will benefit from a shunt, however, is still problematic.

  9. Shunt Devices for the Treatment of Adult Hydrocephalus: Recent Progress and Characteristics

    PubMed Central

    MIYAKE, Hiroji

    2016-01-01

    Various types of shunt valves have been developed during the past 50 years, most of which can be classified into the following categories: (1) fixed differential pressure valves; (2) fixed differential pressure (DP) valves with an antisiphon mechanism; (3) programmable DP valves; (4) programmable DP valves with an antisiphon mechanism; and (5) programmable antisiphon valves. When considering the myriad of possible postoperative condition changes, such as the onset of accidental non-related diseases or trauma in adults, and changes in normal physiological development or anticipation of future shunt removal in children, it has become standard to use the programmable valve as a first choice for cerebrospinal fluid shunting. However, it is still unclear what type of shunt valve is suitable for each individual case. Based on the results of SINPHONI and more recently SINPHONI 2 trials, the programmable DP valve is recommended as the first line shunt valve. The programmable DP valve with an antisiphon mechanism is thought to be beneficial for tall, slender patients, who have a tendency for easily developing complications of overdrainage, however, this type of valve must be used cautiously in obese patients because of the increased risk of underdrainage. Although the current evidence is still insufficient, the programmable antisiphon valve, which costs the same as the programmable DP valve, is also thought to be the first line shunt valve. The quick reference table is applicable for most shunt valves, and for patients with either the ventriculoperitoneal or the lumboperitoneal shunt. PMID:27041631

  10. How shunting inhibition affects the discharge of lumbar motoneurones: a dynamic clamp study in anaesthetized cats

    PubMed Central

    Brizzi, L; Meunier, C; Zytnicki, D; Donnet, M; Hansel, D; d'Incamps, B Lamotte; van Vreeswijk, C

    2004-01-01

    In the present work, dynamic clamp was used to inject a current that mimicked tonic synaptic activity in the soma of cat lumbar motoneurones with a microelectrode. The reversal potential of this current could be set at the resting potential so as to prevent membrane depolarization or hyperpolarization. The only effect of the dynamic clamp was then to elicit a constant and calibrated increase of the motoneurone input conductance. The effect of the resulting shunt was investigated on repetitive discharges elicited by current pulses. Shunting inhibition reduced very substantially the firing frequency in the primary range without changing the slope of the current–frequency curves. The shift of the I–f curve was proportional to the conductance increase imposed by the dynamic clamp and depended on an intrinsic property of the motoneurone that we called the shunt potential. The shunt potential ranged between 11 and 37 mV above the resting potential, indicating that the sensitivity of motoneurones to shunting inhibition was quite variable. The shunt potential was always near or above the action potential voltage threshold. A theoretical model allowed us to interpret these experimental results. The shunt potential was shown to be a weighted time average of membrane voltage. The weighting factor is the phase response function of the neurone that peaks at the end of the interspike interval. The shunt potential indicates whether mixed synaptic inputs have an excitatory or inhibitory effect on the ongoing discharge of the motoneurone. PMID:15169842

  11. Reasons, procedures, and outcomes in ventriculoatrial shunts: A single-center experience

    PubMed Central

    Yavuz, Celal; Demırtas, Sinan; Calıskan, Ahmet; Kamasak, Kaan; Karahan, Oguz; Guclu, Orkut; Yazıcı, Suleyman; Mavıtas, Binali

    2013-01-01

    Background: Ventricular shunts are used to drain cerebrospinal fluid into extra-cranial spaces. Ventriculoatrial (VA) shunts are provided to transfer cerebrospinal fluid from the cerebral ventricle into the right atrium of the heart. A single center experience of indications, procedure, and clinical outcomes in VA shunt was presented in current study. Methods: VA shunts were applied in 10 patients who had repeated previous shunt dysfunction or infection. The reasons, clinical findings, replacement methods, and postoperative clinical follow-ups and outcomes were recorded retrospectively. Results: There were seven female (70%) and three (30%) male patients; their ages ranged from 5 to 13 years (mean ± SD; 8.5 ± 2.6 years). Shunt re-placement reasons were as follows: Shunt occlusion in five patients, intraperitoneal infection in four patients and a distal catheter was kinked and knotted in one patient. Postoperative early complications were seen in one patient as early catheter thrombosis and catheter revision were applied. Late complications were seen in two patients as follows: Catheter infection and infective endocarditis occurred in one patient and pulmonary thrombus occurred in one other patient. There was not any catheter-related mortality observed at the one year follow-up period. Conclusion: VA shunts may be an option for cerebrospinal fluid drainage at necessary conditions. However, sterilization and general training on asepsy and antisepsy are the most important determinants affecting the clinical outcome due to the cardio systemic relationship. PMID:23493480

  12. Shunt Devices for the Treatment of Adult Hydrocephalus: Recent Progress and Characteristics.

    PubMed

    Miyake, Hiroji

    2016-05-15

    Various types of shunt valves have been developed during the past 50 years, most of which can be classified into the following categories: (1) fixed differential pressure valves; (2) fixed differential pressure (DP) valves with an antisiphon mechanism; (3) programmable DP valves; (4) programmable DP valves with an antisiphon mechanism; and (5) programmable antisiphon valves. When considering the myriad of possible postoperative condition changes, such as the onset of accidental non-related diseases or trauma in adults, and changes in normal physiological development or anticipation of future shunt removal in children, it has become standard to use the programmable valve as a first choice for cerebrospinal fluid shunting. However, it is still unclear what type of shunt valve is suitable for each individual case. Based on the results of SINPHONI and more recently SINPHONI 2 trials, the programmable DP valve is recommended as the first line shunt valve. The programmable DP valve with an antisiphon mechanism is thought to be beneficial for tall, slender patients, who have a tendency for easily developing complications of overdrainage, however, this type of valve must be used cautiously in obese patients because of the increased risk of underdrainage. Although the current evidence is still insufficient, the programmable antisiphon valve, which costs the same as the programmable DP valve, is also thought to be the first line shunt valve. The quick reference table is applicable for most shunt valves, and for patients with either the ventriculoperitoneal or the lumboperitoneal shunt. PMID:27041631

  13. Evaluation of LeVeen-shunt patency using Tc-99m labelled macroaggregated albumin.

    PubMed

    Adil, Allah Rakha; Waqar, Amin

    2005-12-01

    A LeVeen peritoneo-venous shunt is placed for intractable ascites. Determination of obstruction site in the shunt tube is a difficult problem. We describe a simple nuclear medicine method using 111MBq (3mCi) of Technetium-99m labeled macro-aggregated albumin injected intraperitoneally. PMID:16398982

  14. Ventriculoperitoneal shunt for treatment of hydrocephalus in a French bulldog puppy

    PubMed Central

    Giacinti, Jolene A.

    2016-01-01

    A 6.5-week-old bulldog was presented with lethargy, anorexia, and stunted growth. A domed skull, ventrolateral strabismus, hypermetria, and delayed hopping were observed. Congenital hydrocephalus was diagnosed and a ventriculoperitoneal shunt was placed. After surgery, a shunt obstruction occurred but resolved with treatment. The puppy responded well and neurological deficits continued to improve after surgery. PMID:26933271

  15. Shunt currents in vanadium flow batteries: Measurement, modelling and implications for efficiency

    NASA Astrophysics Data System (ADS)

    Fink, H.; Remy, M.

    2015-06-01

    Shunt currents are an important factor which must be considered when designing a stack for flow batteries. They lead to a reduction of the coulombic efficiency and can cause furthermore a critical warming of the electrolyte. Shunt currents inevitably appear at bypass connections of the hydraulic system between the single cells of a stack. In this work the shunt currents of a five-celled mini stack of a vanadium flow battery with external hydraulic system and their effects are investigated directly. The external hydraulic system allows the implementation of current sensors for direct measurement of the shunt currents; moreover, the single bypass channels can be interrupted by clamping the tube couplings and with it the shunt currents between the cells when the pumps are off. Thus the shares of losses by cross contamination and by shunt currents are quantified separately by charge conservation measurements. The experimentally gained data are compared to a shunt current model based on a equivalent circuit diagram and the linear equation system derived from it. Experiments and model data are in good agreement. The effects of shunt currents for different flow frame geometries and number of cells in a stack are simulated and presented in this work.

  16. Electroacoustic absorbers: bridging the gap between shunt loudspeakers and active sound absorption.

    PubMed

    Lissek, Hervé; Boulandet, Romain; Fleury, Romain

    2011-05-01

    The acoustic impedance at the diaphragm of an electroacoustic transducer can be varied using a range of basic electrical control strategies, amongst which are electrical shunt circuits. These passive shunt techniques are compared to active acoustic feedback techniques for controlling the acoustic impedance of an electroacoustic transducer. The formulation of feedback-based acoustic impedance control reveals formal analogies with shunt strategies, and highlights an original method for synthesizing electric networks ("shunts") with positive or negative components, bridging the gap between passive and active acoustic impedance control. This paper describes the theory unifying all these passive and active acoustic impedance control strategies, introducing the concept of electroacoustic absorbers. The equivalence between shunts and active control is first formalized through the introduction of a one-degree-of-freedom acoustic resonator accounting for both electric shunts and acoustic feedbacks. Conversely, electric networks mimicking the performances of active feedback techniques are introduced, identifying shunts with active impedance control. Simulated acoustic performances are presented, with an emphasis on formal analogies between the different control techniques. Examples of electric shunts are proposed for active sound absorption. Experimental assessments are then presented, and the paper concludes with a general discussion on the concept and potential improvements. PMID:21568400

  17. 21 CFR 882.5550 - Central nervous system fluid shunt and components.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Central nervous system fluid shunt and components. 882.5550 Section 882.5550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... shunt is a device or combination of devices used to divert fluid from the brain or other part of...

  18. 21 CFR 882.5550 - Central nervous system fluid shunt and components.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Central nervous system fluid shunt and components. 882.5550 Section 882.5550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... shunt is a device or combination of devices used to divert fluid from the brain or other part of...

  19. 21 CFR 882.5550 - Central nervous system fluid shunt and components.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Central nervous system fluid shunt and components. 882.5550 Section 882.5550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... shunt is a device or combination of devices used to divert fluid from the brain or other part of...

  20. 21 CFR 882.5550 - Central nervous system fluid shunt and components.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Central nervous system fluid shunt and components. 882.5550 Section 882.5550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... shunt is a device or combination of devices used to divert fluid from the brain or other part of...

  1. 21 CFR 882.5550 - Central nervous system fluid shunt and components.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Central nervous system fluid shunt and components. 882.5550 Section 882.5550 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... shunt is a device or combination of devices used to divert fluid from the brain or other part of...

  2. Shunt volume dynamics in stroke patients with patent foramen ovale.

    PubMed

    Reichenberger, F; Kaps, M; Seeger, W; Tanislav, C

    2013-09-01

    A variation in right atrial and pulmonary arterial pressure might result in a shunt dynamic across a patent foramen ovale (PFO). In the present study we tested if peak exercise facilitates a restoration of right to left shunt (RLS) in stroke patients who demonstrated a functional PFO closure (no evidence of RLS across an initially demonstrated PFO). In stroke patients with PFO demonstrating a functional closure, the RLS was reassessed on peak exercise using contrast-enhanced transcranial Doppler sonography. The exercise procedure consisted of a cardiopulmonary exercise test with supplementary stress echocardiography for assessment of pulmonary circulation. Four stroke patients with initially PFO curtain pattern and a subsequent functional PFO closure (no evidence for RLS) underwent the procedure. In all four patients a RLS could be resurrected during peak physical exercise after a Valsalva strain. While in two patients peak exercise led to an RLS in a countable range of microembolic signals, in two patients a curtain pattern was obtained. One patient showed evidence for reoccurrence of RLS on peak exercise without a Valsalva strain. The patients with curtain pattern had a better peak exercise performance. Although the systolic pulmonary arterial pressure increased during exercise in all patients, there was no direct correlation with the detected RLS. After a functional PFO closure peak exercise combined with a Valsalva strain facilitates the reoccurrence of RLS in stroke patients. PMID:23743402

  3. Fabrication and characterization of shunted μ-SQUID

    SciTech Connect

    Kumar, Nikhil; Fournier, T.; Courtois, H.; Gupta, Anjan K.

    2014-04-24

    In order to eliminate hysteresis, we have fabricated and characterized niobium based shunted micron size superconducting quantum interference devices (μ-SQUIDs). We find a wide temperature range where these μ-SQUIDs are non-hysteretic in nature and show a very good I{sub c} vs. B oscillations in hysteretic regime and V vs. B oscillations in non-hysteretic regime. Here we report the characteristics of a shunted- μ-SQUID (Wf38LS72D5). In this device we have achieved a large voltage modulation, in non-hysteretic regime, at various temperatures including such as 1.1 mV at 6.62 K with a transfer function V{sub Φ} = 7.2mV/Φ{sub 0}. The figures within the original article PDF file, as supplied to AIP Publishing, were affected by a PDF-processing error. Consequently, the article re-flowed and pagination increased from 3 to 4 pages. This article was updated on 14 May 2014 to correct the PDF-processing error, with the scientific content remaining unchanged. Readers are advised that the replacement article PDF file contains an additional blank page to preserve the original pagination.

  4. Design and measurement of improved capacitively-shunted flux qubits

    NASA Astrophysics Data System (ADS)

    Sears, Adam; Birenbaum, Jeffrey; Hover, David; Gudmundsen, Theodore; Kerman, Andrew; Welander, Paul; Yoder, Jonilyn L.; Gustavsson, Simon; Jin, Xiaoyue; Kamal, Archana; Clarke, John; Oliver, William

    2014-03-01

    The addition of a capacitive or inductive shunt across one of the junctions can alter the coherence properties of a classic flux or RF-SQUID qubit. We have studied the performance of capacitively shunted flux qubits fabricated with MBE aluminum, starting from a 2D coplanar waveguide geometry used in similar high-performance transmon qubits, and measured dispersively. We will detail the importance of design parameters that preserve the flux qubit's anharmonicity and discuss conclusions about materials quality based on calculations of the participation of junction, dielectric, and superconductor components. This research was funded in part by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA); and by the Assistant Secretary of Defense for Research & Engineering under Air Force Contract number FA8721-05-C-0002. All statements of fact, opinion or conclusions contained herein are those of the authors and should not be construed as representing the official views or policies of IARPA, the ODNI, or the U.S. Government Present address: SLAC National Accelerator Laboratory, Menlo Park, CA.

  5. Fabrication and characterization of shunted μ-SQUID

    NASA Astrophysics Data System (ADS)

    Kumar, Nikhil; Fournier, T.; Courtois, H.; Gupta, Anjan K.

    2014-04-01

    In order to eliminate hysteresis, we have fabricated and characterized niobium based shunted micron size superconducting quantum interference devices (μ-SQUIDs). We find a wide temperature range where these μ-SQUIDs are non-hysteretic in nature and show a very good Ic vs. B oscillations in hysteretic regime and V vs. B oscillations in non-hysteretic regime. Here we report the characteristics of a shunted- μ-SQUID (Wf38LS72D5). In this device we have achieved a large voltage modulation, in non-hysteretic regime, at various temperatures including such as 1.1 mV at 6.62 K with a transfer function VΦ = 7.2mV/Φ0. The figures within the original article PDF file, as supplied to AIP Publishing, were affected by a PDF-processing error. Consequently, the article re-flowed and pagination increased from 3 to 4 pages. This article was updated on 14 May 2014 to correct the PDF-processing error, with the scientific content remaining unchanged. Readers are advised that the replacement article PDF file contains an additional blank page to preserve the original pagination.

  6. Relationship between migraine and cardiac and pulmonary right-to-left shunts.

    PubMed

    Wilmshurst, P; Nightingale, S

    2001-02-01

    A relationship between migraine with aura and the presence of right-to-left shunts has been reported in two studies. Right-to-left shunts are also associated with some forms of decompression illness. While conducting research in divers with decompression illness, it was our impression that divers with a large shunt often had a history of migraine with aura in everyday life and after dives. Therefore we routinely asked all divers about migraine symptoms. The medical records of the last 200 individuals referred for investigation of decompression illness were reviewed to determine the association between right-to-left shunts and migraine aura after diving, and migraine in daily life unconnected with diving. Migraine with aura in daily life unconnected with diving occurred significantly more frequently in individuals who had a large shunt which was present at rest (38 of 80; 47.5%) compared with those who had a shunt which was smaller or only seen after a Valsalva manoeuvre (four of 40; 10%) or those with no shunt (11 of 80; 13.8%) (P<0.001). Hemiplegic migraine occurred in 10 divers, each of whom had a shunt that was present at rest; in eight of these cases the shunt was large. The prevalence of migraine without aura was similar in all groups. Post-dive migraine aura was significantly more frequent in individuals who had a large shunt present at rest (21 of 80; 26.3%) compared with those who had a shunt that was smaller or only seen after a Valsalva manoeuvre (five of 40; 12.5%) or no shunt (one of 80; 1.3%) (P<0.001). Thus individuals with a large right-to-left shunt have an increased prevalence of migraine with aura in daily life unconnected with diving, and they also have an increased incidence of migraine aura after dives, but only when the dives liberate venous bubbles. These data suggest the possibility that, in some individuals, right-to-left shunts have a role in the aetiology of migraine with aura. The observations suggest that paradoxical gas embolism may

  7. Pulmonary shunt: a comparison between oxygen and inert gas infusion methods.

    PubMed

    Hlastala, M P; Colley, P S; Cheney, F W

    1975-12-01

    Pulmonary shunt measurement was compared using the standard oxygen (Berggren) technique and a new multiple inert gas infusion (Wagner et al.) technique in 11 mongrel dogs with either regional atelectasis or diffuse pulmonary edema. Relative retentions of sulfur hexafluoride, ethane, cyclopropane, halothane, diethyl ether, and acetone were used to calculate intrapulmonary shunt. Relative dilution of oxygen (Berggren method) was used to calculate total right to left shunt. The two methods gave similar results in the range of 20-80%. At low shunts the oxygen method measured higher values. This is because of the greater relative importance of fixed extrapulmonary shunts at this level and, as well, error in the measurement of PO2. Both techniques are suitable for normal clinical use. PMID:175043

  8. Sound absorption of a finite micro-perforated panel backed by a shunted loudspeaker.

    PubMed

    Tao, Jiancheng; Jing, Ruixiang; Qiu, Xiaojun

    2014-01-01

    Deep back cavities are usually required for micro-perforated panel (MPP) constructions to achieve good low frequency absorption. To overcome the problem, a close-box loudspeaker with a shunted circuit is proposed to substitute the back wall of the cavity of the MPP constructions to constitute a composite absorber. Based on the equivalent circuit model, the acoustic impedance of the shunted loudspeaker is formulated first, then a prediction model of the sound absorption of the MPP backed by shunted loudspeaker is developed by employing the mode solution of a finite size MPP coupled by an air cavity with an impendence back wall. The MPP absorbs mid to high frequency sound, and with properly adjusted electrical parameters of its shunted circuit, the shunted loudspeaker absorbs low frequency sound, so the composite absorber provides a compact solution to broadband sound control. Numerical simulations and experiments are carried out to validate the model. PMID:24437763

  9. Ventricular enlargement due to acute hypernatremia in a patient with a ventriculoperitoneal shunt.

    PubMed

    Andres, Robert H; Pendharkar, Arjun V; Kuhlen, Dominique; Mariani, Luigi

    2010-07-01

    Patients requiring CSF shunts frequently have comorbidities that can influence water and electrolyte balances. The authors report on a case involving a ventriculoperitoneal shunt in a patient who underwent intravenous hyperhydration and withdrawal of vasopressin substitution prior to scheduled high-dose chemotherapy regimen for a metastatic suprasellar germinoma. After acute neurological deterioration, the patient underwent CT scanning that demonstrated ventriculomegaly. A shunt tap revealed no flow and negative opening pressure. Due to suspicion of proximal shunt malfunction, the comatose patient underwent immediate surgical exploration of the ventricle catheter, which was found to be patent. However, acute severe hypernatremia was diagnosed during the procedure. After correction of the electrolyte disturbances, the patient regained consciousness and made a good recovery. Although rare, the effects of acute severe hypernatremia on brain volume and ventricular size should be considered in the differential diagnosis of ventriculoperitoneal shunt failure. PMID:19911884

  10. Indigenous cost-effective peritoneo-venous shunt for refractory ascites.

    PubMed

    Marimuthu, K; Kumar, A Suresh; Sabanathan, S; Gowrishankar, A; Kumar, P Sasi; Rajkumar, J S

    2004-01-01

    About 5% of patients with chronic liver disease develop massive refractory ascites. These patients cease to respond to diuretic therapy and may develop prerenal azotemia. There is a small but definite role for the peritoneo-venous shunt in these patients. In our study of 36 patients, managed with locally made, single-valved peritoneo-venous shunts (GSAIMS shunts), shunt failure and complication rates were assessed postoperatively. There is a definite improvement in quality of life with this cost-effective locally made shunt if patients are selected carefully. Long-term follow-up of these patients is not possible because most of these patients succumb to advanced liver disease. PMID:15285240

  11. An Unusual Complication of Ventriculoperitoneal Shunt: Urinary Bladder Stone Case Report and Literature Review

    PubMed Central

    Xu, Songtao; Sheng, Weixin; Qiu, Yufa; Wang, Jianguo

    2016-01-01

    Introduction: Ventriculoperitoneal (V-P) shunt surgery is the most common technique used for the treatment of hydrocephalus. The migration of ventriculoperitoneal shunt to the bladder is rare. Only two cases have been previously reported in the literature. Case Presentation: We report on a 38-year-old male who had hydrocephalus and V-P shunt for 12 years. Two years ago, he found himself with recurrent urinary tract infections, haematuria and urges incontinence, and then he was diagnosed with bladder perforation and merge stones. The patient had an abdominal operation to cut off and take out the shunt catheter, as well as a transurethral holmium laser lithotripsy. Conclusions: Bladder perforation and stones are rare examples of complications in V-P surgical procedures. Controlling the effective length of the terminal V-P shunt and modifying it appropriately can effectively reduce these complications. PMID:26889393

  12. Laparoscopic Cholecystectomy for Acute Calcular Cholecystitis in a Patient with Ventriculoperitoneal Shunt: A Case Report and Literature Review

    PubMed Central

    Albarrak, Abdullah A.; Khairy, Sami; Ahmed, Alzahrani Mohammed

    2015-01-01

    Management of patients who have ventriculoperitoneal shunt presenting with acute calcular cholecystitis has remained a clinical challenge. In this paper, the hospital course and the follow-up of a patient presenting with acute calcular cholecystitis and ventriculoperitoneal shunt managed with laparoscopic cholecystectomy are presented followed by literature review on the management of acute calcular cholecystitis in patients who have ventriculoperitoneal shunts. PMID:26798543

  13. Relationship between right-to-left shunts and cutaneous decompression illness.

    PubMed

    Wilmshurst, P T; Pearson, M J; Walsh, K P; Morrison, W L; Bryson, P

    2001-05-01

    The presence of a large right-to-left shunt is associated with neurological decompression illness after non-provocative dives, as a result of paradoxical gas embolism. A small number of observations suggest that cutaneous decompression illness is also associated with a right-to-left shunt, although an embolic aetiology of a diffuse rash is more difficult to explain. We performed a retrospective case--control comparison of the prevalence and sizes of right-to-left shunts determined by contrast echocardiography performed blind to history in 60 divers and one caisson worker with a history of cutaneous decompression illness, and 123 historical control divers. We found that 47 (77.0%) of the 61 cases with cutaneous decompression illness had a shunt, compared with 34 (27.6%) of 123 control divers (P<0.001). The size of the shunts in the divers with cutaneous decompression illness was significantly greater than in the controls. Thus 30 (49.2%) of the 61 cases with cutaneous decompression illness had a large shunt at rest, compared with six (4.9%) of the 123 controls (P<0.001). During closure procedures in 17 divers who had cutaneous decompression illness, the mean diameter of the foramen ovale was 10.9 mm. Cutaneous decompression illness occurred after dives that were provocative or deep in subjects without shunts, but after shallower and non-provocative dives in those with shunts. The latter individuals are at increased risk of neurological decompression illness. We conclude that cutaneous decompression illness has two pathophysiological mechanisms. It is usually associated with a large right-to-left shunt, when the mechanism is likely to be paradoxical gas embolism with peripheral amplification when bubble emboli invade tissues supersaturated with nitrogen. Cutaneous decompression illness can also occur in individuals without a shunt. In these subjects, the mechanism might be bubble emboli passing through an 'overloaded' lung filter or autochthonous bubble formation

  14. Choice of valve type and poor ventricular catheter placement: Modifiable factors associated with ventriculoperitoneal shunt failure.

    PubMed

    Jeremiah, Kealeboga Josephine; Cherry, Catherine Louise; Wan, Kai Rui; Toy, Jennifer Ah; Wolfe, Rory; Danks, Robert Andrew

    2016-05-01

    Ventriculoperitoneal (VP) shunt insertion is a common neurosurgical procedure, essentially unchanged in recent years, with high revision rates. We aimed to identify potentially modifiable associations with shunt failure. One hundred and forty patients who underwent insertion of a VP shunt from 2005-2009 were followed for 5-9years. Age at shunt insertion ranged from 0 to 91years (median 44, 26% <18years). The main causes of hydrocephalus were congenital (26%), tumour-related (25%), post-haemorrhagic (24%) or normal pressure hydrocephalus (19%). Fifty-eight (42%) patients required ⩾1 shunt revision. Of these, 50 (88%) were for proximal catheter blockage. The median time to first revision was 108days. Early post-operative CT scans were available in 105 patients. Using a formal grading system, catheter placement was considered excellent in 49 (47%) but poor (extraventricular) in 13 (12%). On univariate analysis, younger age, poor ventricular catheter placement and use of a non-programmable valve were associated with shunt failure. On logistic regression modelling, the independent associations with VP shunt failure were poor catheter placement (odds ratio [OR] 4.9, 95% confidence interval [CI] 1.3-18.9, p=0.02) and use of a non-programmable valve (OR 0.4, 95% CI 0.2-1.0, p=0.04). In conclusion, poor catheter placement (revision rate 77%) was found to be the strongest predictor of shunt failure, with no difference in revisions between excellent (43%) and moderate (43%) catheter placement. Avoiding poor placement in those with mild or moderate ventriculomegaly may best reduce VP shunt failures. There may also be an influence of valve choice on VP shunt survival. PMID:26758704

  15. Portocaval shunt for hepatocyte package: challenging application of small intestinal graft in animal models.

    PubMed

    Iwasaki, Junji; Hata, Toshiyuki; Uemoto, Shinji; Fujimoto, Yasuhiro; Kanazawa, Hiroyuki; Teratani, Takumi; Hishikawa, Shuji; Kobayashi, Eiji

    2013-10-01

    In developing therapeutic alternatives to liver transplantation, we have used the strategy of applying a small intestinal segment as a scaffold for hepatocyte transplantation and also as a portocaval shunt (PCS) system to address both liver dysfunction and portal hypertension. The aim of this study was to investigate the feasibility of such an intestinal segment in animal models. Hepatocytes isolated from luciferase-transgenic Lewis rats were transplanted into jejunal segments of wild-type Lewis rats with mucosa removal without PCS application. Luciferase-derived luminescence from transplanted hepatocytes was stably detected for 30 days. Then, we performed autologous hepatocyte transplantation into the submucosal layer of an isolated and vascularized small intestinal segment in pigs. Transplanted hepatocytes were isolated from the resected left-lateral lobe of the liver. On day 7, hepatocyte clusters and bile duct-like structures were observed histologically. To create an intestinal PCS system in pigs, an auto-graft of the segmental ileum and interposing vessel graft were anastomosed to the portal vein trunk and inferior vena cava. However, thrombi were observed in vessels of the intestinal PCSs. We measured the correlation between infusion pressure and flow volume in whole intestines ex vivo in both species and found that the high pressure corresponding to portal hypertension was still insufficient to maintain the patency of the intestinal grafts. In conclusion, we demonstrated the feasibility of the small intestine as a scaffold for hepatocyte transplantation in rat and pig models, but PCS using an intestinal graft failed to maintain patency in a pig model. PMID:23974217

  16. Comparative histology of pineal calcification.

    PubMed

    Vígh, B; Szél, A; Debreceni, K; Fejér, Z; Manzano e Silva, M J; Vígh-Teichmann, I

    1998-07-01

    The pineal organ (pineal gland, epiphysis cerebri) contains several calcified concretions called "brain sand" or acervuli (corpora arenacea). These concretions are conspicuous with imaging techniques and provide a useful landmark for orientation in the diagnosis of intracranial diseases. Predominantly composed of calcium and magnesium salts, corpora arenacea are numerous in old patients. In smaller number they can be present in children as well. The degree of calcification was associated to various diseases. However, the presence of calcified concretions seems not to reflect a specific pathological state. Corpora arenacea occur not only in the actual pineal tissue but also in the leptomeninges, in the habenular commissure and in the choroid plexus. Studies with the potassium pyroantimonate (PPA) method on the ultrastructural localization of free calcium ions in the human pineal, revealed the presence of calcium alongside the cell membranes, a finding that underlines the importance of membrane functions in the production of calcium deposits. Intrapineal corpora arenacea are characterized by a surface with globular structures. Meningeal acervuli that are present in the arachnoid cover of the organ, differ in structure from intrapineal ones and show a prominent concentric lamination of alternating dark and light lines. The electron-lucent lines contain more calcium than the dark ones. There is a correlation between the age of the subject and the number of layers in the largest acervuli. This suggests that the formation of these layers is connected to circannual changes in the calcium level of the organ. The histological organization of the human pineal is basically the same as that of mammalian experimental animals. Pineal concretions present in mammalian animal species are mainly of the meningeal type. Meningeal cells around acervuli contain active cytoplasmic organelles and exhibit alkaline phosphatase reaction in the rat and mink, an indication of a presumable

  17. Comparative Histology of Plasma Treated Tissue

    NASA Astrophysics Data System (ADS)

    Rick, Kyle

    2009-10-01

    Atmospheric plasmas applied in surgical settings have unique characteristics found in histological results from animal tissue studies. This is evident in both ex vivo bench tissue tests and in vivo fresh tissue. Examples of these histological features are presented as results of a comparative study between plasma treated, common medical argon coagulation, and electrosurgery.

  18. Comparison of outcomes between patients with idiopathic normal pressure hydrocephalus who received a primary versus a salvage shunt.

    PubMed

    Moran, Dane; Hung, Alice; Vakili, Sharif; Fialho, Hugo; Jeon, Lee; Sankey, Eric W; Jusué-Torres, Ignacio; Lu, Jennifer; Goodwin, C Rory; Elder, Benjamin D; Rigamonti, Daniele

    2016-07-01

    Placement of a ventriculoperitoneal (VP) shunt is the treatment of choice for communicating hydrocephalus; however, the extent to which VP shunting is able to relieve symptoms in patients who had previously been treated with cerebrospinal fluid diverting therapy at an outside institution remains unclear. A retrospective review of patients with idiopathic normal pressure hydrocephalus treated with VP shunts at a single institution between 1993 and 2013 was conducted. Patients were classified as having received a primary VP shunt if they had not been previously treated with a VP shunt, ventriculoatrial shunt, lumboperitoneal shunt, or endoscopic third ventriculostomy. Patients were classified as having received a salvage VP shunt if they had been previously treated by one of these four modalities at an outside institution prior to their presentation to our institution. There were 357 patients who received a primary shunt and 33 patients who received a salvage shunt. Patients who had a salvage shunt placed had significantly higher odds of requiring a future revision (54% versus 41%; odds ratio=2.85; 95% confidence interval [CI]: 1.24-6.57; p=0.014). Patients who received a salvage shunt had statistically significantly lower rates of gait improvement at 6months in comparison to patients who received a primary shunt (relative risk=0.35; 95% CI: 0.14-0.87; p=0.025). Despite these findings, there was no significant difference at last follow-up in improvement in gait, continence, and cognition, indicating that outcomes for patients requiring a salvage shunt were comparable to patients receiving a primary shunt. PMID:26898583

  19. Splenopancreatic disconnection. Improved selectivity of distal splenorenal shunt.

    PubMed Central

    Warren, W D; Millikan, W J; Henderson, J M; Abu-Elmagd, K M; Galloway, J R; Shires, G T; Richards, W O; Salam, A A; Kutner, M H

    1986-01-01

    Distal splenorenal shunt (DSRS) improves survival from variceal bleeding in nonalcoholic cirrhotics but not in alcoholic subjects. The metabolic response after DSRS is also different in alcoholic and nonalcoholic cirrhotics. Portal perfusion, quality of blood perfusing the liver, cardiac output, and liver blood flow do not change in nonalcoholics. In alcoholics, portal perfusion is frequently lost (60%), quality of blood perfusing the liver decreases, and cardiac output and liver blood flow increase. It is proposed that portal flow is lost in alcoholics via pancreatic and colonic collaterals after surgery. Elimination of this sump by adding complete dissection of the splenic vein and division of the splenocolic ligament to DSRS (splenopancreatic disconnection, SPD) could preserve portal perfusion, decrease shunt loss of hepatotrophic factor, and improve survival in alcoholic cirrhotics. This report compares data 1 year after surgery in two groups of cirrhotics: group I (8 nonalcoholic; 16 alcoholic) had DSRS without SPD; group II (17 nonalcoholic; 11 alcoholic) received DSRS + SPD. Methods: Portal perfusion grade, cardiac output (CO), liver blood flow (f), hepatic function (GEC), and hepatic volume (vol) were measured before and 1 year after surgery. Shunt loss of hepatotrophic factor was estimated by insulin response (change in plasma concentration over 10 minutes: AUC) after arginine stimulation. Results: Groups I and II were similar before surgery. Metabolically, nonalcoholics remained stable after both DSRS and DSRS + SPD. After standard DSRS, alcoholics lost portal perfusion (75%, p less than 0.05), CO, and f increased (p less than 0.05), and quality of blood perfusing the liver was decreased (GEC/f: p less than 0.05). DSRS + SPD preserved portal perfusion better (p less than 0.05) in alcoholic cirrhotics than did DSRS alone. After DSRS + SPD, the metabolic response in alcoholics resembled that of nonalcoholics. CO, f, and GEC/f remained stable. These data

  20. Reproducibility of histologic classification of gastric cancer.

    PubMed Central

    Palli, D.; Bianchi, S.; Cipriani, F.; Duca, P.; Amorosi, A.; Avellini, C.; Russo, A.; Saragoni, A.; Todde, P.; Valdes, E.

    1991-01-01

    A panel review of histologic specimens was carried out as part of a multi-centre case-control study of gastric cancer (GC) and diet. Comparisons of diagnoses of 100 GCs by six pathologists revealed agreement in histologic classification for about 70-80% of the cancers. Concordance was somewhat higher when using the Lauren rather than the Ming or World Health Organization classification systems. Histologic types from reading biopsy tissue agreed with those derived from surgical specimens for 65-75% of the 100 tumours. Intra-observer agreement in histologic classification, assessed by repeat readings up to 3 years apart by one pathologist, was 95%. The findings indicate that, although overall concordance was good, it is important to standardise diagnoses in multi-centre epidemiologic studies of GC by histologic type. PMID:2039701

  1. Ventriculosternal Shunting for the Management of Hydrocephalus: Case Report of A Novel Technique

    PubMed Central

    Hung Pang, Peter Ka; Chan, Kwong Yau; Ching Kwok, John Kwong

    2015-01-01

    BACKGROUND: Conventional cerebrospinal fluid diversion such as ventriculoperitoneal or ventriculoatrial shunting for the management of hydrocephalus is one of the commonest neurosurgical procedures. However, in selected patients, surgical options are limited when relative contraindications for these operations exist. A patient who underwent ventriculosternal shunting, a novel procedure, is presented with durable and successful outcomes. OBJECTIVE: To demonstrate the feasibility, durability, and safety of ventriculosternal shunting for the management of hydrocephalus. METHODS: A patient with end-stage renal failure and heart failure with recurrent pleural effusion suffered from post–subarachnoid hemorrhage communicating hydrocephalus. Because of the need for continuous ambulatory peritoneal dialysis and the risk of introducing excessive cardiac preloading, conventional shunting was relatively contraindicated. Ventriculosternal shunting was performed by adopting the cancellous matrix of the sternum as the anatomic receptacle for intraosseous cerebrospinal fluid absorption. After placement of the ventricular catheter in the usual manner, the distal end was inserted into the sternum. RESULTS: There was demonstrable clinical and radiological improvement in hydrocephalus by ventriculosternal shunting. Cerebrospinal fluid intraosseous absorption by this novel procedure translated into both physical and cognitive recovery. The procedure was tolerable, effective, and durable, with the patient suffering no complications 3 years after the procedure. CONCLUSION: Ventriculosternal shunting for the management of hydrocephalus is a feasible, safe, and durable surgical treatment option for selected patients when conventional procedures are contraindicated. ABBREVIATION: VS, ventriculosternal PMID:26114598

  2. Pediatric hydrocephalus: Does the shunt device pressure selection affect the outcome?

    PubMed Central

    Sinha, Arvind; Sharma, Anuj; Gupta, Charitesh

    2012-01-01

    Aim: To compare the efficacy of low- versus medium-pressure shunts in pediatric hydrocephalus in a randomized controlled trial. Materials and Methods: Forty patients of pediatric hydrocephalus were randomized into two groups. The Chhabra differential pressure VP shunt (low or medium) was inserted in every patient. Postoperative follow-up was performed for symptomatic improvement and radiological evaluation (by sonography or computed tomography scan) for ventricle hemispheric ratio (VHR). Comparative analysis of pre- and postoperative VHR and need of redo surgery for shunt malformation were carried out to establish outcomes. Results: Nineteen patients had a low-pressure and 21 patients had a medium-pressure shunt inserted. The age of the patients ranged from 1 day to 10 years. The average preoperative VHR in group A was 55.37%, which reduced to 40% postoperatively (P = 0.00005); likewise, the pre- and postoperative VHR in group B were 61.57% and 42%, respectively, which was statistically significant (P = 0.0006). The complications of shunts and incidence of redo shunt surgery in both groups were not found to be statistically significant (P = 0.5614). Conclusions: The study found no significant difference in the outcome of patients with low- or medium-pressure shunt placement in pediatric hydrocephalus. PMID:22529548

  3. Portasystemic shunting versus liver transplantation for the Budd-Chiari syndrome.

    PubMed Central

    Bismuth, H; Sherlock, D J

    1991-01-01

    Over 12 years, 22 patients with the Budd-Chiari syndrome were treated surgically. Eighteen underwent a mesenterico-caval shunt (MCS); two, a side-to-side portacaval shunt; one, a mesenterico-atrial shunt (MAS); and one, a liver transplantation (OLT). One patient died after operation from the precipitating condition, and two MCS grafts that thrombosed were restored. All 21 surviving patients remain well, free from ascites, and all shunts are patent after a mean follow-up of 5.6 +/- 1 years, five patients with more than 10 years' follow-up. This long-term survival achieved by portasystemic shunts suggests that they have a major role in the treatment of the Budd-Chiari syndrome. The authors prefer the mesenterico-caval shunt using a jugular graft. This ensures a total portasystemic shunt, avoids subhepatic surgery, and reduces the long-term risk of prosthetic graft thrombosis. The MAS was reserved for cases with complete caval thrombosis. Patients with significant degrees of caval compression were satisfactorily decompressed by MCS. In patients not promptly treated, the disease progresses to cirrhosis, and such patients must be evaluated for transplantation similarly to those with other hepatopathies. Images Fig. 1. Fig. 3. Fig. 4. Fig. 5A and B. PMID:1953111

  4. Shunt diode analysis using light emission for gallium arsenide solar cell predictability

    NASA Astrophysics Data System (ADS)

    Kilmer, Louis C.; Honsberg, Christiana; Phillips, James E.; Barnett, Allen M.

    The use of light emission as a defect analysis technique has been expanded to better differentiate the types of shunt defects and analyze their effects on GaAs solar cells. Light emission from full-size 2-cm x 2-cm space solar cells was detected, recorded, digitized, and enhanced in order to analyze the low-level light emission and the shunt diode's effects. Shunt diodes are of particular importance because they have been found to be the type of defect which is most likely to degrade and cause failure in GaAs solar cells. To analyze how the shunt diodes affect the quality of the solar cell, the pattern of light emission must be studied. In studying the low-level light emission, it was found that the pattern of light emission is different than that of the high-level light emission. The different light patterns show the changing effects of the shunt diodes. It is concluded that the shunt diode dominates over the junction diode at low values of current and that the junction diode dominates over the shunt diode at high values of current.

  5. Shunt Testing In Vivo: Observational Study of Problems with Ventricular Catheter.

    PubMed

    Czosnyka, Zofia H; Sinha, Rohitiwa; Morgan, James A D; Wawrzynski, James R; Price, Steven J; Garnett, Matthew; Pickard, John D; Czosnyka, M

    2016-01-01

    Most shunt obstructions happen at the inlet of the ventricular catheter. Three hundred six infusion studies from 2007 to 2011 were classified as having a typical pattern of either proximal occlusion or patency. We describe different patterns of shunt ventricular obstruction.Solid block: Cerebrospinal fluid (CSF) aspiration was impossible. Baseline pressure was without pulse waveform (respiratory waveform may be visible). A quick increase of pressure to a level compatible with the shunt's setting was recorded in response to infusion. Distal occlusion of the shunt via transcutaneous compression resulted in a rapid increase in pressure to levels above 50 mmHg. This pattern was attributed to a solid ventricular block.Slit ventricles: At baseline, a pattern similar to that of the solid block was observed. After compression, the pressure increases, the pulse waveform appears, and the intracranial pressure is often stabilized at 25-40 mmHg. It is probable that previously slit ventricles were opened during the test.Partial block: In a partial block of the ventricular catheter by an in-growing choroid plexus, the pulse waveform at baseline was observed and CSF aspiration was possible. During infusion, the pressure increased, but the pulse amplitude disappeared. During the increase in the pressure in the shunt prechamber, the connection with the ventricles is disturbed by repositioning of the plexus.Infusion study via the shunt prechamber is able to visualize ventricular obstruction of the hydrocephalus shunt. PMID:27165935

  6. Controversies: Optic nerve sheath fenestration versus shunt placement for the treatment of idiopathic intracranial hypertension

    PubMed Central

    Spitze, Arielle; Lam, Peter; Al-Zubidi, Nagham; Yalamanchili, Sushma; Lee, Andrew G

    2014-01-01

    Background: Idiopathic intracranial hypertension (IIH) has been increasing in prevalence in the past decade, following the obesity epidemic. When medical treatment fails, surgical treatment options must be considered. However, controversy remains as to which surgical procedure is the preferred surgical option – optic nerve sheath fenestration (ONSF) or cerebrospinal fluid (CSF) shunting – for the long-term treatment of this syndrome. Purpose: To provide a clinical update of the pros and cons of ONSF versus shunt placement for the treatment of IIH. Design: This was a retrospective review of the current literature in the English language indexed in PubMed. Methods: The authors conducted a PubMed search using the following terms: Idiopathic IIH, pseudotumor cerebri, ONSF, CSF shunts, vetriculo-peritoneal shunting, and lumbo-peritoneal shunting. The authors included pertinent and significant original articles, review articles, and case reports, which revealed the new aspects and updates in these topics. Results: The treatment of IIH remains controversial and lacks randomized controlled clinical trial data. Treatment of IIH rests with the determination of the severity of IIH-related visual loss and headache. Conclusion: The decision for ONSF versus shunting is somewhat institution and surgeon dependent. ONSF is preferred for patients with visual symptoms whereas shunting is reserved for patients with headache. There are positive and negative aspects of both procedures, and a prospective, randomized, controlled trial is needed (currently underway). This article will hopefully be helpful in allowing the reader to make a more informed decision until that time. PMID:25449938

  7. [The efficacy of transcatheter embolization of severe arterioportal shunts in hepatocellular carcinoma].

    PubMed

    Hiyoshi, Yukiharu; Beppu, Toru; Okabe, Kazutoshi; Hayashi, Hiromitsu; Masuda, Toshiro; Okabe, Hirohisa; Mizumoto, Takao; Komori, Hiroyuki; Tanaka, Hiroshi; Horino, Kei; Ishiko, Takatoshi; Takamori, Hiroshi; Hirota, Masahiko; Baba, Hideo

    2007-11-01

    Transcatheter arterial embolizations of severe arterioportal shunt (A-P shunt) were performed with steel coils in 3 patients with hepatocellurlar carcinoma (HCC) as shown below. Case 1: A 56-year-old man with HCC associated with portal hypertension (esophageal varices and ascites abnominal pain), portal vein tumor thrombus and severe A-P shunt was performed in critical conditions. Case 2: A 51-year-old man with HCC, lung and adrenal gland metastases was accompanied with severe portal hypertention caused by A-P shunt and was in a harmful condition similar to case 1. Case 3: A 68-year-old woman with HCC associated with autoimmune hepatitis was performed a hepatic resection. Then multiple intrahepatic recurrences appeared 6 months later. A-P shunt made impossible to detect the feeding artery of tumor. After embolization of A-P shunt, esophageal varices and ascites resolved, and abdominal pain improved in cases 1 and 2. In addition, embolization enabled to perform transcatheter arterial chemoembolization in case 3. This procedure is a useful tool to improve various symptoms due to A-P shunt and to continue treatments for HCCs. PMID:18219909

  8. Arterio-venous shunts or low oxygen utilization?

    PubMed

    Rozin, Alexander P

    2010-02-01

    An idea of arteriovenous shunts (AVS) was proposed for explanation of dynamic regulation of oxygenation and venous hyperoxia. A formula enabling calculation of AVS and real CO2 production has recently been derived by comparing data of arterial and venous blood gases. Regarding venous hyperoxia, there is a need to differentiate capillary to tissue transport defect (low oxygen utilisation-LOU) from AVS, which may exist simultaneously. The AVS may be associated with normal or relatively high oxygen utilization from the capillary vessels and increased CO2 production. AVS is proposed to carry protective and 'stealing' properties including renal, cardiac, and pulmonary hemodynamic. Calculations of the AVS may be important for dynamic assessment of vascular and metabolic status and in emergency medicine. PMID:20026514

  9. Loop gain of a spacecraft switched shunt power system

    NASA Astrophysics Data System (ADS)

    Wu, Keng

    1994-10-01

    A novel approach of deriving the loop gain of a spacecraft switched shunt power system is presented. The system hardware elements contain both the analog and the digital components. Transfer functions of the analog circuits are easily identified employing the conventional approach. Gain function of the digital block is however conceived following a quite unconventional route. The digital gain is shown to include the effects of comparator thresholds, digital clock, shift register, sinusoidal amplitude, and ac frequency. The dependence of the digital gain on voltage thresholds, clocking period, and the integrational property of threshold comparator is expected. The dependence on sinusoidal amplitude contradicts the traditional concept of small signal analysis. The overall loop gain in the analytic form yields a computational result that matches the actual measurement very well. This fact proves, to some extent, the validity of the digital gain function and the basis of its derivation.

  10. Microwave power heterojunction bipolar transistors fabricated with thermal shunt bathtub

    SciTech Connect

    Bozada, C.A.; Barlage, D.W.; Barrette, J.P.

    1995-12-31

    Heterojunction bipolar transistor devices and circuits were fabricated using thermal shunt and bathtub thermal management techniques. Broadband cascode MMICs exhibited 10 - 14 dB gain at an output power of 2.5 - 3.0 Watts across 7 - 11 GHz. A 200 {mu}m{sup 2} common-emitter unit cell achieved 7 - 8 dB linear power gain and 40% power-added efficiency at a noise power ratio (NPR) of 18 dBc at 12 GHz. Under single tone measurements at 12 GHz, the unit cell achieved 52% power-added efficiency, with 9.5 dB linear gain, 8 dB power gain and 240 mW output power at 5 V bias.

  11. Shunt Diode Designs in Li/cf Shuttle Batteries

    NASA Technical Reports Server (NTRS)

    Miller, D.; Higgins, R.

    1984-01-01

    Although Li/CF cells and batteries have an excellent safety record, they are included with other battery systems that require additional safety precautions. One precaution suggested is the inclusion of shunt diodes into these batteries. The benefits of this addition are examined. All cells tested at elevated temperatures vent regardless of length of time between being fully discharged and reversed or inclusion of the diode in the system. Cells discharged at ambient temperatures all show a relatively quick reversal, but stabilize at voltages that are high enough that the diodes are not functioning. Cells tested at depressed temperatures reverse the deepest of all cells tested, with the deepest reversal occurring very early in the test and voltages recovering to above -0.60 volts near the end of the tests. Anode limited cells will eliminate the venting during hot reversal.

  12. Shunt diode designs in Li/CF Shuttle batteries

    NASA Astrophysics Data System (ADS)

    Miller, D.; Higgins, R.

    1984-09-01

    Although Li/CF cells and batteries have an excellent safety record, they are included with other battery systems that require additional safety precautions. One precaution suggested is the inclusion of shunt diodes into these batteries. The benefits of this addition are examined. All cells tested at elevated temperatures vent regardless of length of time between being fully discharged and reversed or inclusion of the diode in the system. Cells discharged at ambient temperatures all show a relatively quick reversal, but stabilize at voltages that are high enough that the diodes are not functioning. Cells tested at depressed temperatures reverse the deepest of all cells tested, with the deepest reversal occurring very early in the test and voltages recovering to above -0.60 volts near the end of the tests. Anode limited cells will eliminate the venting during hot reversal.

  13. Electro-clinical follow-up of shunted hydrocephalic children.

    PubMed

    Varfis, G; Berney, J; Beaumanoir, A

    1977-01-01

    In a survey of 29 hydrocephalic children treated by ventriculoatrial shunt (Holter valve) with a follow-up of 4 years, EEG records before the operation and at least once a year thereafter, the authors can support the view that an epileptogenic focus has developed around the place of insertion of the ventricular catheter in 19 cases, leading to epileptic seizures in 17 up to now. Thus the incidence of convulsions in this particular group of patients is 0.59 (17/29), the limits of confidence 95% being 0.39-0.76. The irritative abnormalities occur usually during the second year after the operation and the delay for the onset of clinical seizures is variable. The age at operation seems to influence the occurrence of the epileptogenic scar. The type of hydrocephalus and especially the presence of an associated cerebral focal lesion can be of importance in the development of clinical seizures. PMID:405183

  14. Carotid Baroreceptor Stimulation and Arteriovenous Shunts for Resistant Hypertension.

    PubMed

    Paivanas, Nicholas; Bisognano, John D; Gassler, John P

    2015-01-01

    Pharmacologic therapy for hypertension is effective for the majority of patients with hypertension, but there is a subset of the population with treatment-resistant hypertension who cannot achieve their blood pressure goal despite taking multiple medications. Since these patients are at increased risk of cardiovascular disease and end-organ damage, additional therapies must be considered. This review discusses several novel interventional therapies-including baroreflex activation therapy, baroreceptor stenting, and creation of an arteriovenous shunt-that may provide alternative options for blood pressure control in those with treatment-resistant hypertension. All of these therapies remain investigational, and each has its own strengths and weaknesses that will be critical to assess as they come to market. PMID:27057291

  15. Sequential Switching Shunt Maximum Power Point Regulator (S3MPPR)

    NASA Astrophysics Data System (ADS)

    Blanes, J. M.; Garrigos, A.; Carrasco, J. A.; Weinberg, A. H.; Ejea, J. B.; Sanchis, E.; Farreres, A.; Maset, E.; Soto, A.; de la Cruz, F.

    2011-10-01

    This paper presents the implementation of a Sequential Switching Shunt Maximum Power Point Regulator (S3MPPR). The S3MPPR is the evolution of the traditional S3R where the fixed reference, used by the main error amplifier, is replaced by an MPPT voltage reference. With this variation, the system corresponds to a non-regulated bus topology but with the dynamic characteristics of a regulated one and with the ability to track the MPP of the solar array. This work focuses on this topic, studying the best way to implement the S3MPPR in a geostationary telecommunication satellite. In order to validate the proposal, a 1.6 kW prototype has been implemented and many tests have been carried out with the prototype, all of them showing the good behaviour of the converter.

  16. A SQUID gradiometer module with large junction shunt resistors

    NASA Astrophysics Data System (ADS)

    Qiu, Yang; Liu, Chao; Zhang, Shu-Lin; Zhang, Guo-Feng; Wang, Yong-Liang; Li, Hua; Zeng, Jia; Kong, Xiang-Yan; Xie, Xiao-Ming

    2014-08-01

    A dual-washer superconducting quantum interference device (SQUID) with a loop inductance of 350 pH and two on-washer integrated input coils is designed according to conventional niobium technology. In order to obtain a large SQUID flux-to-voltage transfer coefficient, the junction shunt resistance is selected to be 33 Ω. A vertical SQUID gradiometer module with a baseline of 100 mm is constructed by utilizing such a SQUID and a first-order niobium wire-wound antenna. The sensitivity of this module reaches about 0.2 fT/(cm·Hz1/2) in the white noise range using a direct readout scheme, i.e., the SQUID is directly connected to an operational amplifier, in a magnetically shielded room. Some magnetocardiography (MCG) measurements with a sufficiently high signal-to-noise ratio (SNR) are demonstrated.

  17. Role of Glyoxylate Shunt in Oxidative Stress Response.

    PubMed

    Ahn, Sungeun; Jung, Jaejoon; Jang, In-Ae; Madsen, Eugene L; Park, Woojun

    2016-05-27

    The glyoxylate shunt (GS) is a two-step metabolic pathway (isocitrate lyase, aceA; and malate synthase, glcB) that serves as an alternative to the tricarboxylic acid cycle. The GS bypasses the carbon dioxide-producing steps of the tricarboxylic acid cycle and is essential for acetate and fatty acid metabolism in bacteria. GS can be up-regulated under conditions of oxidative stress, antibiotic stress, and host infection, which implies that it plays important but poorly explored roles in stress defense and pathogenesis. In many bacterial species, including Pseudomonas aeruginosa, aceA and glcB are not in an operon, unlike in Escherichia coli In P. aeruginosa, we explored relationships between GS genes and growth, transcription profiles, and biofilm formation. Contrary to our expectations, deletion of aceA in P. aeruginosa improved cell growth under conditions of oxidative and antibiotic stress. Transcriptome data suggested that aceA mutants underwent a metabolic shift toward aerobic denitrification; this was supported by additional evidence, including up-regulation of denitrification-related genes, decreased oxygen consumption without lowering ATP yield, increased production of denitrification intermediates (NO and N2O), and increased cyanide resistance. The aceA mutants also produced a thicker exopolysaccharide layer; that is, a phenotype consistent with aerobic denitrification. A bioinformatic survey across known bacterial genomes showed that only microorganisms capable of aerobic metabolism possess the glyoxylate shunt. This trend is consistent with the hypothesis that the GS plays a previously unrecognized role in allowing bacteria to tolerate oxidative stress. PMID:27036942

  18. Tunable acoustic waveguide based on vibro-acoustic metamaterials with shunted piezoelectric unit cells

    NASA Astrophysics Data System (ADS)

    Kwon, Byung-Jin; Jung, Jin-Young; Lee, Dooho; Park, Kwang-Chun; Oh, Il-Kwon

    2015-10-01

    We propose a new class of acoustic waveguides with tunable bandgaps (TBs) by using vibro-acoustic metamaterials with shunted periodic piezoelectric unit cells. The unit metamaterial cells that consist of a single crystal piezoelectric transducer and an electrical shunt circuit are designed to induce a strong vibro-acousto-electrical coupling, resulting in a tunable acoustic bandgap as well as local structural resonance and Bragg scattering bandgaps. The present results show that the TB frequency can be actively controlled and the transmission loss of the acoustic wave can be greatly improved by simply changing the inductance values in the shunt circuit.

  19. Primary ventriculo-peritoneal shunts in treatment of hydrocephalus associated with myelomeningocele

    PubMed Central

    Stark, G. D.; Drummond, M. B.; Poneprasert, S.; Robarts, F. H.

    1974-01-01

    In 50 children suffering from open myelomeningocele, a ventriculo-peritoneal shunt was employed as the primary procedure for control of hydrocephalus. In 11 cases the system was ultimately replaced by a ventriculo-atrial shunt, though this may not always have been necessary. In the remaining 39 patients satisfactory control of hydrocephalus was achieved. Obstruction, particularly of the peritoneal catheter, occurred frequently in the first 6 months but no revisions were required after 2 years. It is concluded that while ventriculo-peritoneal and ventriculo-atrial shunts achieve comparable success in controlling hydrocephalus, the former, due to the relatively innocuous complications, offers significant long-term advantages. PMID:4593818

  20. Intracranial hypotension after syringopleural shunting in posttraumatic syringomyelia: Case report and review of the literature.

    PubMed

    Summers, Johanne C; Vellore, Yagnesh; Chan, Patrick C H; Rosenfeld, Jeffrey V

    2015-01-01

    We report a case of a 45-year-old male with a syringopleural shunt who developed intracranial hypotension. The patient presented with 2 weeks history of worsening headache and back pain, on a background of having had a syringopleural shunt inserted for a thoracic posttraumatic syrinx. Computerized tomography imaging of the brain revealed bilateral subdural fluid collections. Magnetic resonance imaging appearances of spinal and intracranial pachymeningeal enhancement confirmed intracranial hypotension. We present a rare case of intracranial hypotension secondary to syringopleural shunting in a patient with posttraumatic syringomyelia. PMID:25972956

  1. Waste Package Neutron Absorber, Thermal Shunt, and Fill Gas Selection Report

    SciTech Connect

    V. Pasupathi

    2000-01-28

    Materials for neutron absorber, thermal shunt, and fill gas for use in the waste package were selected using a qualitative approach. For each component, selection criteria were identified; candidate materials were selected; and candidates were evaluated against these criteria. The neutron absorber materials evaluated were essentially boron-containing stainless steels. Two candidates were evaluated for the thermal shunt material. The fill gas candidates were common gases such as helium, argon, nitrogen, carbon dioxide, and dry air. Based on the performance of each candidate against the criteria, the following selections were made: Neutron absorber--Neutronit A978; Thermal shunt--Aluminum 6061 or 6063; and Fill gas--Helium.

  2. A Case of Discontinued Proximal Limb of a Ventriculoperitoneal Shunt With Patent Fibrous Tract.

    PubMed

    Bermo, Mohammed; Leung, Alan S; Matesan, Manuela

    2016-06-01

    Radionuclide shuntogram is important in the evaluation of cerebrospinal fluid (CSF) shunts complications such as mechanical failure, malpositioning, pseudocyst, or overdrainage. We present here a case of congenital hydrocephalus and posterior fossa cyst with multiple shunt procedures and revisions with breakage of the proximal tube of the ventriculoperitoneal shunt but preserved CSF drainage through the patent fibrous tract. Careful correlation with SPECT/CT images helped confirm the breakage and exclude CSF leak outside of the tract, which was suspected on planar images. PMID:26914568

  3. Treatment of Syringomyelia due to Chiari Type I Malformation with Syringo-Subarachnoid-Peritoneal Shunt

    PubMed Central

    Akakın, Akın; Yılmaz, Baran; Kılıç, Türker

    2015-01-01

    Chiari type I malformation is a tonsillar herniation more than 3 mm from the level of foramen magnum, with or without concurrent syringomyelia. Different surgical treatments have been developed for syringomyelia secondary to Chiari's malformations: craniovertebral decompression with or without plugging of the obex, syringo-subarachnoid, syringo-peritoneal, and theco-peritoneal shunt placement. Shunt placement procedures are useful for neurologically symptomatic large-sized syrinx. In this paper, authors define the first successful treatment of a patient with syringomyelia due to Chiari type I malformation using a pre-defined new technique of syringo-subarachnoid-peritoneal shunt with T-tube system. PMID:25932303

  4. Testing of cerebrospinal compensatory reserve in shunted and non-shunted patients: a guide to interpretation based on an observational study.

    PubMed Central

    Czosnyka, M; Whitehouse, H; Smielewski, P; Simac, S; Pickard, J D

    1996-01-01

    OBJECTIVE--To design a computerised infusion test to compensate for the disadvantages of Katzman's lumbar infusion method: inadequate accuracy of estimation of the resistance to cerebrospinal fluid outflow and poor predictive value in normal pressure hydrocephalus. METHODS--Accuracy was improved by intracranial pressure signal processing and model analysis for measurement of cerebrospinal compensatory variable. These include the CSF outflow resistance, brain compliance, pressure-volume index, estimated sagittal sinus pressure, CSF formation rate, and other variables. Infusion may be made into the lumbar space, ventricles, or, when assessing shunt function in vivo, the shunt chamber. RESULTS AND CONCLUSIONS--The computerised test has been used for five years in a multicentre study in 350 hydrocephalic patients of various ages, aetiologies, and states of cerebrospinal compensation. The principles of using the test to characterise different types of CSF circulatory disorders in patients presenting with ventricular dilatation, including brain atrophy and normal and high pressure hydrocephalus, are presented and illustrated. Previous studies showed a positive correlation between cerebrospinal compensatory variables and the results of shunting, but such a prediction remains difficult in idiopathic normal pressure hydrocephalus, particularly in elderly patients. The technique is helpful in the assessment of shunt malfunction, including posture-related overdrainage, over-drainage related to the nocturnal B wave activity, and proximal or distal shunt obstruction. The appendix presents an introduction of the mathematical modelling of CSF pressure volume-compensation included in computerised infusion test software. Images PMID:8778261

  5. [Metal implant sensitivity: clinical and histological presentation].

    PubMed

    Hartmann, D; Letulé, V; Schneider, J J; Flaig, M J

    2016-05-01

    Metal implant sensitivity (intolerance) can cause pain, reduced mobility, loosening of the implant and skin rashes. Knowledge of differential diagnoses, histology and appropriate diagnostics are essential for proper diagnosis. To outline typical clinical signs and histology in metal-implant-associated skin lesions we present three exemplary patients from our implant allergy outpatient department and give an overview of the current literature regarding metal implant sensitivity. In patients with a negative patch test the lymphocyte transformation test may reveal metal sensitization. Even "pure" titanium alloys may contain traces of nickel. The histology of implant-associated skin reactions goes from teleangiectatic postimplantation erythema to eczema and vasculitis. Based on the synopsis of history, clinical picture, allergological testing and histology, metal implant sensitivity can be diagnosed more precisely. PMID:27090521

  6. Optimizing the Shunting Schedule of Electric Multiple Units Depot Using an Enhanced Particle Swarm Optimization Algorithm

    PubMed Central

    Jin, Junchen

    2016-01-01

    The shunting schedule of electric multiple units depot (SSED) is one of the essential plans for high-speed train maintenance activities. This paper presents a 0-1 programming model to address the problem of determining an optimal SSED through automatic computing. The objective of the model is to minimize the number of shunting movements and the constraints include track occupation conflicts, shunting routes conflicts, time durations of maintenance processes, and shunting running time. An enhanced particle swarm optimization (EPSO) algorithm is proposed to solve the optimization problem. Finally, an empirical study from Shanghai South EMU Depot is carried out to illustrate the model and EPSO algorithm. The optimization results indicate that the proposed method is valid for the SSED problem and that the EPSO algorithm outperforms the traditional PSO algorithm on the aspect of optimality. PMID:27436998

  7. Optimizing the Shunting Schedule of Electric Multiple Units Depot Using an Enhanced Particle Swarm Optimization Algorithm.

    PubMed

    Wang, Jiaxi; Lin, Boliang; Jin, Junchen

    2016-01-01

    The shunting schedule of electric multiple units depot (SSED) is one of the essential plans for high-speed train maintenance activities. This paper presents a 0-1 programming model to address the problem of determining an optimal SSED through automatic computing. The objective of the model is to minimize the number of shunting movements and the constraints include track occupation conflicts, shunting routes conflicts, time durations of maintenance processes, and shunting running time. An enhanced particle swarm optimization (EPSO) algorithm is proposed to solve the optimization problem. Finally, an empirical study from Shanghai South EMU Depot is carried out to illustrate the model and EPSO algorithm. The optimization results indicate that the proposed method is valid for the SSED problem and that the EPSO algorithm outperforms the traditional PSO algorithm on the aspect of optimality. PMID:27436998

  8. A broken heart: Right-to-left shunt in the setting of normal cardiac pressures

    PubMed Central

    Gomperts, Natalie; Fowler, Robert; Horlick, Eric; McLaughlin, Peter

    2008-01-01

    A patent foramen ovale (PFO) is a common structural cardiac variant occurring in approximately 30% of the general population. Patients are usually asymptomatic because the defect is flap-like and does not permit significant left-to-right shunting. However, pathological conditions that result in cardiac rotation or higher than normal right atrial pressures can reverse the normal left atrial to right atrial pressure gradient and cause a right-to-left shunt through a PFO. If the right-to-left shunt is persistent, systemic hypoxemia or paradoxical emboli may result. The present report describes a case of refractory hypoxemia in a critically ill patient with a PFO who had a right-to-left shunt with normal right-sided cardiac pressures. PMID:18340396

  9. A broken heart: right-to-left shunt in the setting of normal cardiac pressures.

    PubMed

    Gomperts, Natalie; Fowler, Robert; Horlick, Eric; McLaughlin, Peter

    2008-03-01

    A patent foramen ovale (PFO) is a common structural cardiac variant occurring in approximately 30% of the general population. Patients are usually asymptomatic because the defect is flap-like and does not permit significant left-to-right shunting. However, pathological conditions that result in cardiac rotation or higher than normal right atrial pressures can reverse the normal left atrial to right atrial pressure gradient and cause a right-to-left shunt through a PFO. If the right-to-left shunt is persistent, systemic hypoxemia or paradoxical emboli may result. The present report describes a case of refractory hypoxemia in a critically ill patient with a PFO who had a right-to-left shunt with normal right-sided cardiac pressures. PMID:18340396

  10. Graphs and Grammars for Histology: An Introduction

    PubMed Central

    Prewitt, Judith M. S.

    1979-01-01

    The invention of the microscope disclosed a whole new world, that of the hitherto invisibly small. Histologic evidence as revealed by the microscope has become a cornerstone of medical diagnosis, and efforts are now being made to lay foundations so that the medical visual information processing burden can be alleviated significantly by cost-effective automation. This paper lays image processing foundations by presenting a graph-theoretic and syntactic model for the analysis of histologic patterns, and presents results to date.

  11. What are the implications of the spontaneous spleno-renal shunts in liver cirrhosis?

    PubMed Central

    2009-01-01

    Background Although significant advances are expected to be made in the assessment of the portal hypertension-related complications, the prognostic role of spleno-renal shunts has not been fully explored so far. Clarifying this aspect could help tackle the life-treating events occurring in patients suffering from liver cirrhosis. The aim of the study was to analyze the relationships between the spleno-renal shunts presence at doppler ultrasound and the liver cirrhosis complications. Methods Design: eighty one patients out of 129 formed the study population (35 females). Chronic liver damage in these patients was caused by HCV (66), HBV (2), alcohol abuse (2) or unknown etiology, likely non-alcoholic steatohepatitis (11). Setting: two Liver Units of university/primary hospitals in Southern Italy. Main outcome measures: grading of esofageal varices; detection of ascites: assessment of hepatic encephalopathy; evaluation of liver cirrhosis severity; tracking hepatocellular carcinoma; doppler features of spleno-renal shunts and splenic flow velocity; spleen longitudinal diameter at sonography. Results The prevalence of spleno-renal shunts was 18.5%, without no difference concerning the etiology (HCV versus non-HCV, p = 0.870); the prevalence of hepatocellular carcinoma in patients with spleno-renal shunts was superior to that of patients without them (Pearson Chi-square, p = 0.006, power of sample size 74%), also after adjustment for liver decompensation (p = 0.024). The median score of hepatic encephalopathy in patients with and without spleno-renal shunts was similar, i.e., 0 (range, 0-2) versus 0 (0 - 3), p = 0.67. The median splenic vein flow velocity in patients with spleno-renal shunts was significantly inferior to that of patients without them, i.e., 13 cm/sec (95% confidence intervals, 6-18) versus 21 cm/sec (17-24), p < 0.0001. By far the largest percentage of large esophageal varices was in patients without spleno-renal shunts (p = 0.005). In contrast, the

  12. Superconducting FCL using a combined inducted magnetic field trigger and shunt coil

    DOEpatents

    Tekletsadik, Kasegn D.

    2007-10-16

    A single trigger/shunt coil is utilized for combined induced magnetic field triggering and shunt impedance. The single coil connected in parallel with the high temperature superconducting element, is designed to generate a circulating current in the parallel circuit during normal operation to aid triggering the high temperature superconducting element to quench in the event of a fault. The circulating current is generated by an induced voltage in the coil, when the system current flows through the high temperature superconducting element.

  13. Mycotic pulmonary artery aneurysm: an unusual complication of ventriculo-atrial shunt

    PubMed Central

    Gelfand, Elliot T.; Callaghan, John C.

    1981-01-01

    A 23-year-old man with a previous ventriculo-atrial shunt for a pinealoma developed a febrile illness and heart murmur. The condition was thought to be caused by subacute bacterial endocarditis. Further investigation, however, revealed a mycotic left pulmonary artery aneurysm, which was treated by means of a left pneumonectomy with cardiopulmonary bypass. Such an aneurysm represents yet another complication of ventriculo-atrial shunting for hydrocephalus. Images PMID:15216218

  14. Palliative embolisation for intrapulmonary shunting in lepidic predominant adenocarcinoma of the lung

    PubMed Central

    Tan, Joanne Yue-Ai; Walters, Darren L.; Poon, Karl; Zimmerman, Paul; Aldons, Pat

    2015-01-01

    Lepidic predominant adenocarcinoma (LPA) (formerly known as bronchioalveolar carcinoma) has rarely been reported to cause refractory hypoxia with intrapulmonary shunting [1–7]. We describe a case who underwent the palliative strategy of intravascular right lower pulmonary artery embolisation with an 18 mm Amplatzer II vascular plug to reduce intrapulmonary shunting. This is the first report we are aware of using this minimally invasive procedure to treat this condition. PMID:26236621

  15. Optimal Surgical Management Using a Classic Blalock-Taussig Shunt for an Infected Pseudoaneurysm After a Modified Blalock-Taussig Shunt Procedure.

    PubMed

    Okada, Noritaka; Murayama, Hiroomi; Hasegawa, Hiroki

    2016-05-01

    We present 2 cases of a 3-month-old girl and boy who were diagnosed with an infected pseudoaneurysm 2 months after undergoing left-sided modified Blalock-Taussig shunt (mBTS) operations for pulmonary atresia. Because the shunts in both cases were nearly obstructed, they underwent a 2-stage surgical approach: classic BTS operations through a right thoracotomy to establish sufficient pulmonary flow and infected graft removal through a median sternotomy after close observation of the state of the aneurysms. By utilizing autologous tissue from a different thoracic entry, both patients were successfully managed and recovered without any recurrence of infection. PMID:27106441

  16. Standard Trabeculectomy and Ex-PRESS Miniature Glaucoma Shunt: A Comparative Study and Literature Review

    PubMed Central

    Zunz, Eran; Tzur, Rotem; Kurtz, Shimon; Shemesh, Gabi

    2015-01-01

    Purpose: The aim of this study was to compare the efficacy and safety between standard trabeculectomy and the Ex-PRESS shunt implantation. Methods: A retrospective review of the records of 100 eyes of 100 patients who underwent trabeculectomy or Ex-PRESS shunt implantation between July 2010 and June 2012 was conducted. Of these, 61 (61%) eyes underwent trabeculectomy and 39 (39%) eyes underwent Ex-PRESS shunt implantation. Demographic information, glaucoma type, surgical details, preoperative, and postoperative data including intraocular pressure (IOP), number of medications, reoperation, and occurrence of any complications were recorded. Results: No differences in IOP reduction or number of postoperative IOP-lowering medications were demonstrated between the 2 procedures. Success rates were 86.9% for trabeculectomy and 84.6% for Ex-PRESS shunt. Rates of failure and hypotony were not significantly different between the groups. No parameter was correlated with success or failure of any procedure. Conclusions: Standard trabeculectomy and Ex-PRESS shunt have similar efficacy and safety profiles. As the Ex-PRESS shunt is considerably more expensive, its use may be unjustified, especially as a primary procedure. PMID:24633088

  17. Bedside nuclear probe for detection and quantification of left to right intracardiac shunts.

    PubMed Central

    Gould, B A; Turner, J; Keeling, D H; Ring, N J; Cox, R R; Marshall, A J

    1988-01-01

    A cadmium telluride nuclear probe with an Elscint gamma camera was used to detect and measure left to right intracardiac shunts at the bedside in 34 patients. Fifteen also had right heart catheterisation and oximetric measurement of the shunt. For the nuclear technique 740 MBq (20 mCi) of technetium-99m pertechnetate was injected into the right antecubital vein and the pulmonary to systemic flow ratio (QP:QS) was measured by the gamma variate technique. Data were not obtained in four patients because the nuclear probe failed in three patients and one storage disc was corrupted. Data from the gamma camera were lost in another patient. When the size of the shunt measured by the nuclear probe was compared with that measured by the oximetric technique the mean difference (SD of mean difference) was 0.36 (SD 0.78) and when it was compared with the gamma camera it was 0.08 (SD 0.67). Analysis of scatter plots showed that the larger the shunt, the larger the discrepancy. Twenty four of 29 data sets showed complete agreement between the nuclear probe and gamma camera on the size of the shunt. Any differences were small. These data indicate that left to right intracardiac shunts may be measured accurately by a nuclear probe at the bedside in either the coronary care unit or outpatient department. PMID:2835974

  18. Prevention options for ventriculoperitoneal shunt infections: a retrospective analysis during a five-year period

    PubMed Central

    Wu, Xing; Liu, Qin; Jiang, Xiaofei; Zhang, Tao

    2015-01-01

    Shunt infection is the most common and dreaded complication in patients with hydrocephalus. For the purpose of reducing the high morbidity and mortality, how to prevent is a vital step. A retrospective analysis of 384 CSF cerebrospinal fluid (CSF) shunt procedures was undertaken from 2006 to 2010 in our neurosurgery department. Infection diagnosis was established by subjecting the CSF to biochemical and microbiological parameters. The patients’ demographic and clinical characteristics, various treatment procedures and outcome were evaluated. The infection rate of ventriculoperitoneal (VP) shunt was 12.5% in 2006, which dropped to 2% and stabilized at lower level from 2008. The most common causes of hydrocephalus were traumatic injury and brain tumor. Fever and consciousness disturbance were the major clinical symptoms. Gram-negative rods episodes was the most frequently isolated microorganisms accounting for 58%, followed by S. aureus , S. epidermidis and Staphylococcus haemolyticus. With the removal of shunt and intravenous antibiotics therapy, 82% of the patients survived. Majority of the isolates were sensitive to the carbopenem antibiotics and vancomycin. The mean length of hospital stay was 47 days. Prompt shunt removal and perioperative antibiotic prophylaxis seems to be essential for the survival of patients with VP shunt infection. PMID:26770643

  19. Mechanism for measurement of flow rate of cerebrospinal fluid in hydrocephalus shunts.

    PubMed

    Rajasekaran, Sathish; Kovar, Spencer; Qu, Peng; Inwald, David; Williams, Evan; Qu, Hongwei; Zakalik, Karol

    2014-01-01

    The measurement of the flow rate of cerebrospinal fluid (CSF) or existence of CSF flow inside the shunt tube after shunt implant have been reported as tedious process for both patients and doctors; this paper outlines a potential in vitro flow rate measurement method for CSF in the hydrocephalus shunt. The use of implantable titanium elements in the shunt has been proposed to allow for an accurate temperature measurement along the shunt for prediction of CSF flow rate. The CSF flow velocity can be deduced by decoupling the thermal transfer in the measured differential time at a pair of measurement spots of the titanium elements. Finite element analyses on the fluidic and thermal behaviors of the shunt system have been conducted. Preliminary bench-top measurements on a simulated system have been carried out. The measured flow rates, ranging from 0.5 mm/sec to 1.0 mm/sec, which is clinically practical, demonstrate good agreements with the simulation results. PMID:25570411

  20. Integrated fuel cell stack shunt current prevention arrangement

    DOEpatents

    Roche, Robert P.; Nowak, Michael P.

    1992-01-01

    A fuel cell stack includes a plurality of fuel cells juxtaposed with one another in the stack and each including a pair of plate-shaped anode and cathode electrodes that face one another, and a quantity of liquid electrolyte present at least between the electrodes. A separator plate is interposed between each two successive electrodes of adjacent ones of the fuel cells and is unified therewith into an integral separator plate. Each integral separator plate is provided with a circumferentially complete barrier that prevents flow of shunt currents onto and on an outer peripheral surface of the separator plate. This barrier consists of electrolyte-nonwettable barrier members that are accommodated, prior to the formation of the integral separator plate, in corresponding edge recesses situated at the interfaces between the electrodes and the separator plate proper. Each barrier member extends over the entire length of the associated marginal portion and is flush with the outer periphery of the integral separator plate. This barrier also prevents cell-to-cell migration of any electrolyte that may be present at the outer periphery of the integral separator plate while the latter is incorporated in the fuel cell stack.

  1. Oculo-peritoneal shunt: draining aqueous humor to the peritoneum.

    PubMed

    Maldonado-Junyent, Ana; Maldonado-Bas, Arturo; Gonzalez, Andrea; Pueyrredón, Francisco; Maldonado-Junyent, María; Maldonado-Junyent, Arturo; Rodriguez, Diego; Bulacio, Mariano

    2015-01-01

    In 2010, there were estimated to be approximately 60.5 million people with glaucoma. This number is expected to increase to 79.6 million by 2020. In 2010, there were 8.4 million people with bilateral blindness caused by glaucoma, and this number is expected in increase to 11.2 million by 2020. Filtering implants are special devices that have been developed to reduce intraocular pressure in patients with refractory glaucoma. The success rate of these implants is relatively low, and they continue to fail over time. To avoid failure caused by the formation of scar tissue around the implants, attempts have been made to drain the aqueous humor to various sites, including the venous system, lacrimal sac, sinuses, and conjunctival fornix. Recently, a system to shunt aqueous humor from the anterior chamber to the peritoneum has been developed. The surgical technique involved in this system is a modification of the technique currently used by neurosurgeons for the treatment of hydrocephalus. We present the first case operated using this technique. PMID:25945537

  2. Cellular and shunt conductances of toad bladder epithelium.

    PubMed

    Gordon, L G

    1978-12-29

    Toad urinary bladders were mounted in Ussing-type chambers and volt-age-clamped. At nonzero voltages only, small fluctuations in current, delta I, and therefore in tissue conductance, delta Gt, were detected. These fluctuations were caused by the smooth muscle of the underlying tissue which could be monitored continuously and simultaneously with the current, I. Inhibition of the smooth muscle contraction with verapamil (2 X 10(-5) M) abolished the fluctuations in I and Gt. Amiloride (10(-4) M) had no significant effect on the magnitude of delta Gt, oxytocin increased Gt without affecting delta Gt, and mucosal hypertonicity produced by mannitol increased delta Gt. These results are consistent with the hypothesis that two parallel pathways exist for passive current flow across the toad urinary bladder: one, the cellular pathway, was not affected by smooth muscle activity; the other, the paracellular pathway, was the route whose conductance was altered by the action of the smooth muscle. Thus the relationship between the cellular and shunt conductances of the epithelium of the toad urinary bladder, under a variety of conditions, can be investigated by utilizing the effects of the movement of the smooth muscle. PMID:110941

  3. Hyperglucagonemia and hyperkinetic circulation after portocaval shunt in the rat

    SciTech Connect

    Kravetz, D.; Arderiu, M.; Bosch, J.; Fuster, J.; Visa, J.; Casamitjana, R.; Rodes, J.

    1987-02-01

    The study was aimed at investigating whether increased portal venous inflow (PVI) after portocaval shunt (PCS) in the rat is the result of selective splanchnic vasodilatation or whether it is part of a generalized circulatory disturbance. Rats with PCS and sham-operated controls were studied 2 wk after surgery by measuring cardiac output (CO), PVI, and hepatic artery flow (HAF) with radioactive microspheres (V Cr and UC). Plasma glucagon (GL) was measured by radioimmunoassay. PCS rats had increased CO and reduced arterial pressure and total peripheral resistance. PVI was markedly increased, but this appeared to be part of a generalized circulatory disturbance, since when PVI is expressed as percent of CO no difference is observed between PCS and sham-operated rats, indicating the absence of a preferential splanchnic vasodilatation. GL increased after PCS, and significant correlations were observed between GL and CO and between GL and PVI. HAF increased after PCS but did not compensate the loss of portal flow, evidence by a lower total hepatic flow in PCS rats. These results suggest that PCS induces a hyperkinetic circulatory state in which increased PVI represents its splanchnic manifestation and that increased GL release may be in part responsible for these hemodynamic changes.

  4. Effects of isradipine and other calcium antagonists on arteriovenous-shunt flow in anesthetized rabbits and cats

    SciTech Connect

    Hof, R.P.

    1989-04-17

    The effects of vasodilators on arteriovenous (AV)-shunt flow was investigated in anesthetized cats and rabbits, using the tracer microsphere method. In cats, the calcium antagonist isradipine reduced AV-shunt flow; verapamil showed a similar tendency and nicardipine was without effect. Dihydralazine strongly increased, but nitroglycerin and dipyridamole decreased AV-shunt flow. In rabbits, the effects of isradipine and verapamil were similar to those seen in cats. Sodium nitroprusside had no effect, whereas prazosin, minoxidil, and the potassium-channel activator cromakalim increased AV-shunt flow. The contrasting effects of drugs sharing the same mechanism of action suggest that target-tissue selectivity is more important than the mechanism of action. An increase of AV-shunt flow is unlikely to be beneficial but could be associated with a number of undesirable side effects. It might negatively affect migraine sufferers and, if AV-shunt dilatation shows no tolerance development, it represents an unnecessary hemodynamic burden for the heart.

  5. Histological types of polypoid cutaneous melanoma II.

    PubMed

    Knezević, Fabijan; Duancić, Vjekoslav; Sitić, Sanda; Horvat-Knezević, Anica; Benković, Vesna; Ramić, Snjezana; Kostović, Kresimir; Ramljak, Vesna; Vrdoljak, Danko Velemir; Stanec, Mladen; Bozović, Angelina

    2007-12-01

    The aim of this study was to ascertain which histological types of melanoma can clinically and morphologically appear as polypoid melanomas. In 645 cases of primary cutaneous melanoma we have analyzed criteria for diagnosis of polypoid cutaneous melanoma and afterwards we have analyzed growth phase in each polypoid melanoma, histological type of atypical melanocytes, the number of epidermal ridges which are occupied by atypical melanocytes, and distribution according to age, sex and location, as well as the disease free survival. According to the criteria for polypoid melanomas we have found 147 (22.8%) polypoid cutaneous melanomas. Analyzing the growth phases, histological types of atypical melanocytes and the number of affected epidermal ridges in the group of polypoid melanomas we have ascertained 2 (1.4%) ALMs, 4 (2.8%) LMMs, 42 (28.6%) SSMs and 99 (67.2%) NMs. Our conclusion is that polypoid cutaneous melanomas are morphological forms of various histological melanoma types (ALM, LMM, SSM and NM) and they can all display polypoid morphological form. Polypoid cutaneous melanomas are most often of nodular histological type. PMID:18217457

  6. [Gastritis from a histological point of view].

    PubMed

    Vieth, M; Stolte, M

    2006-06-01

    Since the rediscovery of spiral-shaped gastric bacteria in 1983 by Warren and Marshal numerous detailed facts have enlarged our knowledge base for a better understanding of gastritis. The WHO classified Helicobacter as a class 1 carcinogen. Helicobacter plays a role in many diseases of the upper GI tract (gastric and duodenal ulcer, MALT lymphoma, and gastric cancer). Knowledge of the interaction between bacterium and host led to an improvement of the diagnosis of gastritis. Unfortunately endoscopy, histology, and patient's symptoms do not correlate with each other. Therefore, gastritis is a purely histological diagnosis. A histological diagnosis always needs to be accompanied by an etiological cause of the inflammation. Only when this information is given a clinical consequence can be drawn from a histological diagnosis. In Germany the so-called ABCD scheme of gastritis is widely used (A: autoimmune gastritis, B: bacterial gastritis, C: chemical reactive gastritis, D: other forms of gastritis). At least two antrum and two corpus biopsies (matrix diagnostics) are necessary to reach representative tissue with an acceptable probability. If less than these four (minimal standard) biopsies are taken, the histological diagnosis will remain uncertain. PMID:16612608

  7. Comprehensive histological evaluation of bone implants.

    PubMed

    Rentsch, Claudia; Schneiders, Wolfgang; Manthey, Suzanne; Rentsch, Barbe; Rammelt, Stephan

    2014-01-01

    To investigate and assess bone regeneration in sheep in combination with new implant materials classical histological staining methods as well as immunohistochemistry may provide additional information to standard radiographs or computer tomography. Available published data of bone defect regenerations in sheep often present none or sparely labeled histological images. Repeatedly, the exact location of the sample remains unclear, detail enlargements are missing and the labeling of different tissues or cells is absent. The aim of this article is to present an overview of sample preparation, staining methods and their benefits as well as a detailed histological description of bone regeneration in the sheep tibia. General histological staining methods like hematoxylin and eosin, Masson-Goldner trichrome, Movat's pentachrome and alcian blue were used to define new bone formation within a sheep tibia critical size defect containing a polycaprolactone-co-lactide (PCL) scaffold implanted for 3 months (n = 4). Special attention was drawn to describe the bone healing patterns down to cell level. Additionally one histological quantification method and immunohistochemical staining methods are described. PMID:24504113

  8. Comprehensive histological evaluation of bone implants

    PubMed Central

    Rentsch, Claudia; Schneiders, Wolfgang; Manthey, Suzanne; Rentsch, Barbe; Rammelt, Stephan

    2014-01-01

    To investigate and assess bone regeneration in sheep in combination with new implant materials classical histological staining methods as well as immunohistochemistry may provide additional information to standard radiographs or computer tomography. Available published data of bone defect regenerations in sheep often present none or sparely labeled histological images. Repeatedly, the exact location of the sample remains unclear, detail enlargements are missing and the labeling of different tissues or cells is absent. The aim of this article is to present an overview of sample preparation, staining methods and their benefits as well as a detailed histological description of bone regeneration in the sheep tibia. General histological staining methods like hematoxylin and eosin, Masson-Goldner trichrome, Movat’s pentachrome and alcian blue were used to define new bone formation within a sheep tibia critical size defect containing a polycaprolactone-co-lactide (PCL) scaffold implanted for 3 months (n = 4). Special attention was drawn to describe the bone healing patterns down to cell level. Additionally one histological quantification method and immunohistochemical staining methods are described. PMID:24504113

  9. Ventriculo-bipleural shunt as last resort in a 4-year-old child in whom a VP and VA shunt failed.

    PubMed

    Ratliff, Miriam; Unterberg, Andreas; Bächli, Heidi

    2016-03-01

    The authors present the unusual case of a 4-year-old boy who had a complex history of posthemorrhagic hydrocephalus and who underwent more than 40 surgeries related to this condition. In the course of trying to treat his condition, ventriculoperitoneal, ventriculoatrial, and ventriculopleural shunts were inserted and failed. The child presented with a dysfunction of his shunt system. A ventriculopleural shunt was inserted, but within days the patient developed dyspnea as a clinical symptom of pleural effusion that required repeated thoracentesis. A bipleural drainage system was inserted, and no relevant pleural effusions developed during the follow-up period. Although the authors' experience is based on a single case, they do suggest bipleural drainage in patients with clinically relevant pleural effusions when the more common alternatives are not a good choice. Bipleural drainage might particularly be an option in children, who are prone to pleural effusion because of the smaller absorbing pleural surface. The authors reviewed the English-language literature on PubMed dating back to 1952. To their knowledge, this is the only published case in which a patient was treated with a ventriculo-bipleural shunt. PMID:26613270

  10. The International Histological Classification of Tumours*

    PubMed Central

    Sobin, L. H.

    1981-01-01

    This article reviews the development of the WHO project on the histological classification of tumours, which has included the establishment of several collaborating centres and has involved more than 300 pathologists in over 50 countries. The project has resulted in the publication, over the last 14 years, of 25 volumes in the first series of the International Histological Classification of Tumours (IHCT), each giving a classification of tumours specific to a certain site. The classifications are based primarily on the microscopic characteristics of the tumours and are concerned with morphologically identifiable cell types and histological patterns as seen by means of light microscopy and conventional staining techniques. The article also describes the relationship between IHCT and other classification and coding systems and assesses possible future developments that may result from new approaches to diagnosis. PMID:6978190

  11. The internal mammary artery as a shunt in a noncyanotic infant with hemitruncus: surgical and anesthetic management.

    PubMed

    Mahan, Vicki L; Stevens, Randy M; Mesia, Cesar I; Schwartz, Roy E; Moulick, Achintya N

    2016-08-01

    The internal mammary artery (IMA) has been used as a systemic-to-pulmonary artery shunt in selected patients with congenital heart disease. Growth and development of hypoplastic pulmonary arteries have been described. We discuss the surgical and anesthetic management of an infant with an atretic-thrombosed right pulmonary artery originating from the ascending aorta in whom the IMA was used to create a systemic-to-pulmonary artery shunt after failure of a previous shunt and later successful pulmonary artery reconstruction. The IMA should be considered as an alternative conduit in patients requiring a systemic-to-pulmonary artery shunt for growth of pulmonary arteries. PMID:27290936

  12. Appendicitis in Dar es Salaam, histological pattern.

    PubMed

    Mbembati, N A; Lema, L E; Mwakyoma, H A; Ussiri, E V

    1996-03-01

    Histology of 378 appendicectomy specimens submitted to the Histopathology Department of Muhimbili Medical Centre from its surgical wards over a 10 year period (1985 to 1994) were reviewed. There were 185 cases (48.9 pc) of acute appendicitis, 101 cases (26.7 pc) of chronic appendicitis, 74 (19.6 pc) normal appendices and 13 cases (3.5 pc) schistosomal appendicitis. There were two cases of tuberculous appendicitis and two cases of mucocele of the appendix. Apart from the high frequency of chronic appendicitis the histological findings in this study compare well with findings reported from other studies. PMID:8653771

  13. Right-to-left shunt is common in chronic migraine.

    PubMed

    Nahas, S J; Young, W B; Terry, R; Kim, A; Van Dell, T; Guarino, A J; Silberstein, S D

    2010-05-01

    Our aim was to determine the prevalence of right-to-left shunt (RtLS) in patients with chronic migraine (CM), and to correlate the presence and grade of RtLS with aura and neurological symptoms, and duration and severity of disease. The prevalence of RtLS in migraine without aura is similar to that of the general population (between 20 and 35%). In migraine with aura, the prevalence is much higher (approximately 50%). The prevalence in CM, with or without aura, is unknown. Consecutive patients between the ages of 18 and 60 years with CM attending a tertiary care specialty headache clinic over an 8-week period were eligible. There were 131 patients in the study. A structured diagnostic interview was performed. Bubble transcranial Doppler with Valsalva manoeuvre determined RtLS presence and grade. Sixty-six percent (86/131) of patients had RtLS, a statistically significantly greater rate than those reported in the general population and in migraine with or without aura (P < 0.001). There was no difference in RtLS rate or grade between those with and those without aura. Specific headache features and the presence of neurological symptoms were similar between those with and those without RtLS. Compared with both the general population and the episodic migraine population (with and without aura), patients with CM, with or without aura, are more likely to have RtLS. The clinical implications of our findings need to be determined. PMID:19732069

  14. External lumbar drain: A pragmatic test for prediction of shunt outcomes in idiopathic normal pressure hydrocephalus

    PubMed Central

    Chotai, Silky; Medel, Ricky; Herial, Nabeel A.; Medhkour, Azedine

    2014-01-01

    Background: The consensus on most reliable supplemental test to predict the shunt responsiveness in patients with idiopathic normal pressure hydrocephalus (iNPH) is lacking. The aim of this study is to discuss the utility of external lumbar drain (ELD) in evaluation of shunt responsiveness for iNPH patients. Methods: A retrospective review of 66 patients with iNPH was conducted. All patients underwent 4-day ELD trial. ELD-positive patients were offered ventriculoperitoneal shunt (VPS) surgery. The primary outcome evaluation parameters were gait and mini mental status examination (MMSE) assessment. The family and patient perception of improvement was accounted for in the outcome evaluation. Results: There were 38 male and 28 female with mean age of 74 years (range 45-88 years). ELD trial was positive in 86% (57/66) of patients. No major complications were encountered with the ELD trial. A total of 60 patients (57 ELD-positive, 3 ELD-negative) underwent VPS insertion. The negative ELD trial (P = 0.006) was associated with poor outcomes following shunt insertion. The positive ELD trial predicted shunt responsiveness in 96% patients (P < 0.0001, OR = 96.2, CI = 11.6-795.3). A receiver operating characteristic (ROC) curve analysis revealed that the ELD trial is reasonably accurate in differentiating shunt responder from non-responder in iNPH patients (area under curve = 0.8 ± 0.14, P = 0.02, CI = 0.52-1.0). The mean follow-up period was 12-months (range 0.3-3 years). The significant overall improvement after VPS was seen in 92% (55/60). The improvement was sustained in 76% of patients at mean 3-year follow-up. The number of comorbid conditions (P = 0.034, OR = 4.15, CI = 1.2-9.04), and a history of cerebrovascular accident (CVA) (P = 0.035, OR = 4.4, CI = 1.9-14.6) were the predictors of poor outcome following shunt surgery. Conclusion: The positive ELD test predicted shunt responsiveness in 96% of patients. With adequate technique, maximal results with minimal

  15. Complete Intestinal Obstruction and Necrosis as a Complication of a Ventriculoperitoneal Shunt in Children

    PubMed Central

    Zhao, Rui; Shi, Wei; Yu, Jianzhong; Gao, Xiaofeng; Li, Hao

    2015-01-01

    Abstract Ventriculoperitoneal (VP) shunt complications are common, but abdominal complications are rare. The objective of this report is to present 2 cases of intestinal obstruction due to a VP shunt and review the literature for data on this rare occurrence. A 4-month-old boy received surgical resection of a medulloblastoma and a VP shunt was inserted to manage progressive hydrocephalus. Two months later, he was admitted with intermittent vomiting, and plain abdominal radiography showed complete intestinal obstruction. Emergency laparotomy revealed an adhesive intestinal obstruction around the catheter, and approximately 5 cm of necrotic ileum was resected. His recovery was uneventful. In the second case, a 6-year-old boy was diagnosed with a primary nongerminomatous malignant germ cell tumor and a VP shunt was place to treat hydrocephalus. Two weeks after the first course of chemotherapy, he went into a coma; computed tomography demonstrated enlargement of the tumor and gross total resection was performed. Two weeks later, he developed abdominal distention; plain radiography showed intestinal obstruction and laparotomy revealed adhesive intestinal obstruction around the catheter with 15 cm of necrotic ileum. The necrotic bowel was resected. Unfortunately, the patient developed sepsis and despite treatment remained in a vegetative state. Medline, Central, Embase, and Google Scholar databases were searched up to May 9, 2014, using the terms VP shunt, shunting, and/or intestinal obstruction. Only cases involving children or adolescents were included. Eleven reports involving patients with abdominal complications resulting from a VP shunt for hydrocephalus were identified. The dates of the reports spanned from 1971 to 2014. Volvulus was the most common cause of VP shunt-related obstruction, and mechanical obstruction due to twisting of the catheter the second most common. Only 1 case in the literature review was related to intestinal adhesions. Treatment in most

  16. Simulations reveal adverse hemodynamics in patients with multiple systemic to pulmonary shunts.

    PubMed

    Esmaily-Moghadam, Mahdi; Murtuza, Bari; Hsia, Tain-Yen; Marsden, Alison

    2015-03-01

    For newborns diagnosed with pulmonary atresia or severe pulmonary stenosis leading to insufficient pulmonary blood flow, cyanosis can be mitigated with placement of a modified Blalock-Taussig shunt (MBTS) between the innominate and pulmonary arteries. In some clinical scenarios, patients receive two systemic-to-pulmonary connections, either by leaving the patent ductus arteriosus (PDA) open or by adding an additional central shunt (CS) in conjunction with the MBTS. This practice has been motivated by the thinking that an additional source of pulmonary blood flow could beneficially increase pulmonary flow and provide the security of an alternate pathway in case of thrombosis. However, there have been clinical reports of premature shunt occlusion when more than one shunt is employed, leading to speculation that multiple shunts may in fact lead to unfavorable hemodynamics and increased mortality. In this study, we hypothesize that multiple shunts may lead to undesirable flow competition, resulting in increased residence time (RT) and elevated risk of thrombosis, as well as pulmonary overcirculation. Computational fluid dynamics-based multiscale simulations were performed to compare a range of shunt configurations and systematically quantify flow competition, pulmonary circulation, and other clinically relevant parameters. In total, 23 cases were evaluated by systematically changing the PDA/CS diameter, pulmonary vascular resistance (PVR), and MBTS position and compared by quantifying oxygen delivery (OD) to the systemic and coronary beds, wall shear stress (WSS), oscillatory shear index (OSI), WSS gradient (WSSG), and RT in the pulmonary artery (PA), and MBTS. Results showed that smaller PDA/CS diameters can lead to flow conditions consistent with increased thrombus formation due to flow competition in the PA, and larger PDA/CS diameters can lead to insufficient OD due to pulmonary hyperfusion. In the worst case scenario, it was found that multiple shunts can lead to

  17. Hypoxia and GABA shunt activation in the pathogenesis of Alzheimer's disease.

    PubMed

    Salminen, Antero; Jouhten, Paula; Sarajärvi, Timo; Haapasalo, Annakaisa; Hiltunen, Mikko

    2016-01-01

    We have previously observed that the conversion of mild cognitive impairment to definitive Alzheimer's disease (AD) is associated with a significant increase in the serum level of 2,4-dihydroxybutyrate (2,4-DHBA). The metabolic generation of 2,4-DHBA is linked to the activation of the γ-aminobutyric acid (GABA) shunt, an alternative energy production pathway activated during cellular stress, when the function of Krebs cycle is compromised. The GABA shunt can be triggered by local hypoperfusion and subsequent hypoxia in AD brains caused by cerebral amyloid angiopathy. Succinic semialdehyde dehydrogenase (SSADH) is a key enzyme in the GABA shunt, converting succinic semialdehyde (SSA) into succinate, a Krebs cycle intermediate. A deficiency of SSADH activity stimulates the conversion of SSA into γ-hydroxybutyrate (GHB), an alternative route from the GABA shunt. GHB can exert not only acute neuroprotective activities but unfortunately also chronic detrimental effects which may lead to cognitive impairment. Subsequently, GHB can be metabolized to 2,4-DHBA and secreted from the brain. Thus, the activation of the GABA shunt and the generation of GHB and 2,4-DHBA can have an important role in the early phase of AD pathogenesis. PMID:26617286

  18. The Value of Programmable Shunt Valves for the Management of Subdural Collections in Patients with Hydrocephalus

    PubMed Central

    Alexiou, George A.; Mihos, Evaggelos; Fotakopoulos, George; Voulgaris, Spyridon

    2013-01-01

    Background. The aim of the present study was to assess the value of electromagnetic programmable shunt valves for the treatment of subdural collections. Methods. Adult patients with hydrocephalus of various causes that were treated with programmable shunt valves during the last ten years were retrospectively studied. In 127 patients, 139 electromagnetic programmable shunt valves were implanted. Results. A nontraumatic subdural fluid collection was detected in 12 patients. The treatment of these patients consisted of reprogramming of the valve's opening pressure. In 5 patients small subdural hematomas were detected; 4 of these patients were treated by raising the opening pressure alone and one patient required surgical drainage and change of the pressure setting. Traumatic chronic subdural hematomas were detected in 6 patients. These patients were treated by surgical drainage and readjustment of the valve's opening pressure. Conclusion. The ability to treat a shunt-related complication, such as a subdural fluid collection, by reprogramming the valve's opening pressure to a higher setting is an advantage over nonprogrammable valves, and it enables the opening pressure to be slowly lowered once the fluid collection is reabsorbed. Based on our results, we believe that programmable shunt valves should be preferred. PMID:24453855

  19. Quantitative measurement of intrapulmonary and extrapulmonary right-to-left shunt.

    PubMed

    Jones, H A; Stradling, J R; Clark, J C; Davies, E E; Rozkovec, A

    1983-05-01

    We have developed a new technique that enables the shunting of blood from the right to the left side of the circulation to be partitioned into a cardiac and a lung component. The effects of recirculation are minimal, and the method does not require on-line data analysis. Quantitative estimates of these components have been made in two normal dogs and in five patients with raised pulmonary arterial pressures, some of whom were known to have a patent foramen ovale. The results were compared with oxygen shunt measured during air breathing. A poorly soluble gas, nitrogen, radiolabelled with 13N in solution is injected first into a central vein while matched samples of blood are drawn from the pulmonary artery and the aorta. A second solution containing 13N is injected into the right ventricle and sampled from the aorta only. Standardized gamma-counting techniques were used to analyze both the injected radioactivity and the radioactivity in the samples. These two measurements enable us to calculate the total right-to-left shunt, the pulmonary shunt, and by subtraction the extrapulmonary cardiac shunt. PMID:6863103

  20. [Lymphangiomyomatosis with chylous ascites treatment successfully by peritoneo-venous shunting].

    PubMed

    Kimura, M; Morikawa, T; Takeuchi, K; Furuie, H; Fukimura, M; Mikami, R; Kakuta, Y; Kawamura, S; Tashiro, Y

    1996-05-01

    A 49-year-old woman was admitted to our hospital because of coughing and dyspnea. A chest roentogenogram showed emphysematous changes and a diffuse reticular shadow. A high-resolution CT scan of the chest showed many small cysts throughout the lungs. Lymphangiomyomatosis was diagnosed after examination of a specimen obtained by transbronchial biopsy. Abdominal distention due to chylous ascites developed during the hospital stay despite anti-estrogen therapy. Because the ascites was resistant to conservative therapy, we decided to begin peritoneo-venous shunting with a Denver Shunt system. After the operation, the abdominal distention was controlled for 1 year and 11 months, at which time the patient died of respiratory and heart failure with pneumonia. At autopsy, the shunt was patent and functional although about 900 ml of serous ascites fluid was present. An adenocarcinoma was found in the upper lobe of the right lung, but it may not have been related to the lymphangiomyomatosis. Peritoneovenous shunting with a Denver Shunt can be used to treat chylous ascites due to lymphangiomyomatosis when conservative therapy is insufficient. PMID:8753114

  1. Radionuclide quantitation of right-to-left intracardiac shunts in children

    SciTech Connect

    Peter, C.A.; Armstrong, B.E.; Jones, R.H.

    1981-09-01

    A simple, noninvasive method for measurement of right-to-left intracardiac shunts would enhance the management of patients with congenital heart disease. This study describes application of data processing techniques used previously in dye-indicator curves to data recorded during the initial transit of radioactive bolus through the central circulation. Radionuclide angiocardiograms were performed in 20 children, mean age 30 months, immediately after cardiac catheterization for congenital heart disease. The radionuclide data recorded over the carotid artery were used to replace arterial sampling required for dye indicators, and forward triangles were fitted to calculate the right-to-left shunt in an approach similar to that of Wood for indicator-dilution curves. Ten of the children had right-to-left shunts by Fick and radionuclide measurement, and 10 of the children with septal defects had no right-to-left shunt by either technique. Both the radionuclide and Fick measurements correlated well (r . 0.95). Therefore, radionuclide angiocardiographic data may be used for accurate calculation of right-to-left shunts in small children, eliminating the need for arterial sampling.

  2. The relationship of subarachnoid hemorrhage and the need for postoperative shunting.

    PubMed

    Vale, F L; Bradley, E L; Fisher, W S

    1997-03-01

    The incidence of chronic hydrocephalus requiring shunting after aneurysmal subarachnoid hemorrhage (SAH) is not precisely known. The authors investigated whether the need for ventriculoperitoneal (VP) shunting can be predicted by initial Hunt and Hess grade or Fisher computerized tomography score. One hundred eight patients who presented with SAH and underwent 116 surgical procedures for aneurysm clipping were evaluated retrospectively to determine the incidence of chronic hydrocephalus. Chronic hydrocephalus was defined as clinically and radiographically demonstrated hydrocephalus that lasted 2 weeks or longer after the original hemorrhage and that required shunting. All SAH patients were managed in a similar fashion with induced hypervolemia, relative hemodilution, and hypertension complemented by a course of calcium channel blockers. The majority of patients underwent perioperative extracranial ventricular drainage to allow intraoperative brain relaxation and to assist intracranial pressure management. The overall mortality rate of the study group was 17%. Of the surviving patients, 20% underwent VP shunt placement secondary to chronic hydrocephalus. There were no statistically significant relationships between chronic hydrocephalus and patient age or gender, aneurysm type and size, or use of a perioperative drain. There was a high clinical correlation between chronic hydrocephalus and admission Hunt and Hess grades and Fisher grades (p < 0.05). All of the patients who survived a second bleeding episode and almost 46% of the patients who presented with intraventricular hemorrhage required placement of a VP shunt. The authors present predictive tables of chronic hydrocephalus based on the patient's admission Hunt and Hess grade and Fisher classification. PMID:9046303

  3. Constitutively active endothelial Notch4 causes lung arteriovenous shunts in mice

    PubMed Central

    Jelin, Eric B.; Ng, Jennifer; Wu, Jianfeng; Carlson, Timothy R.; Wu, Xiaoqing; Looney, Mark R.; Wang, Rong A.

    2010-01-01

    Lung arteriovenous (AV) shunts or malformations cause significant morbidity and mortality in several distinct clinical syndromes. For most patients with lung AV shunts, there is still no optimal treatment. The underlying molecular and cellular etiology for lung AV shunts remains elusive, and currently described animal models have insufficiently addressed this problem. Using a tetracycline-repressible system, we expressed constitutively active Notch4 (Notch4*) specifically in the endothelium of adult mice. More than 90% of mice developed lung hemorrhages and respiratory insufficiency and died by 6–7 wk after gene expression began. Vascular casting and fluorescent microsphere analysis showed evidence of lung AV shunts in affected mice. Cessation of Notch4* expression reversed these pathophysiological effects. Assessment of the vascular morphology revealed enlarged, tortuous vessels in the lungs that resembled arteriovenous malformations. By using whole lung organ culture, we demonstrated the effects of constitutively active Notch4 on the lung vasculature to be a primary lung phenomenon. Together, our results indicate the importance of Notch signaling in maintaining the lung vasculature and offer a new, reliable model with which to study the pathobiology of lung arteriovenous shunts and malformations. PMID:19933399

  4. Psammomatous Melanotic Schwannoma: A Challenging Histological Diagnosis

    PubMed Central

    Merat, Rastine; Szalay-Quinodoz, Ildiko; Laffitte, Emmanuel; Kaya, Gürkan

    2015-01-01

    Psammomatous melanotic schwannoma (PMS) is a rare pigmented tumor that can be part of the Carney complex. Here, we describe the case of a 35-year-old female patient presenting an isolated subcutaneous PMS. Histopathological analysis could not formally exclude the malignant nature of the tumor. The challenging histological diagnosis and consequently the management of the patient are described. PMID:27047937

  5. Histology. Notes for Students of Animal Husbandry.

    ERIC Educational Resources Information Center

    Price, Charles J.; Reed, Josephine E.

    This document approaches the subject of Histology by way of simple independent unicellular organisms through the lower levels of cell organization and specialization to a detailed study of the highly complex tissues of vertebrate animals. Emphasis is placed on structure, but function is explained in some detail. The relationships between tissues…

  6. Cirrhosis - discharge

    MedlinePlus

    ... to your stomach) Placement of a tube or shunt ( TIPS or TIPSS ) to help prevent too much ... varices Cirrhosis Primary biliary cirrhosis Transjugular intrahepatic portosystemic shunt (TIPS) Patient Instructions How to read food labels ...

  7. New Colors for Histology: Optimized Bivariate Color Maps Increase Perceptual Contrast in Histological Images

    PubMed Central

    Kather, Jakob Nikolas; Weis, Cleo-Aron; Marx, Alexander; Schuster, Alexander K.; Schad, Lothar R.; Zöllner, Frank Gerrit

    2015-01-01

    Background Accurate evaluation of immunostained histological images is required for reproducible research in many different areas and forms the basis of many clinical decisions. The quality and efficiency of histopathological evaluation is limited by the information content of a histological image, which is primarily encoded as perceivable contrast differences between objects in the image. However, the colors of chromogen and counterstain used for histological samples are not always optimally distinguishable, even under optimal conditions. Methods and Results In this study, we present a method to extract the bivariate color map inherent in a given histological image and to retrospectively optimize this color map. We use a novel, unsupervised approach based on color deconvolution and principal component analysis to show that the commonly used blue and brown color hues in Hematoxylin—3,3’-Diaminobenzidine (DAB) images are poorly suited for human observers. We then demonstrate that it is possible to construct improved color maps according to objective criteria and that these color maps can be used to digitally re-stain histological images. Validation To validate whether this procedure improves distinguishability of objects and background in histological images, we re-stain phantom images and N = 596 large histological images of immunostained samples of human solid tumors. We show that perceptual contrast is improved by a factor of 2.56 in phantom images and up to a factor of 2.17 in sets of histological tumor images. Context Thus, we provide an objective and reliable approach to measure object distinguishability in a given histological image and to maximize visual information available to a human observer. This method could easily be incorporated in digital pathology image viewing systems to improve accuracy and efficiency in research and diagnostics. PMID:26717571

  8. Emergency management of an acute tension pneumocephalus following ventriculoperitoneal shunt surgery for normal pressure hydrocephalus.

    PubMed

    Aydoseli, Aydın; Akcakaya, Mehmet Osman; Aras, Yavuz; Boyali, Osman; Unal, Omer Faruk

    2013-01-01

    Tension pneumocephalus is a rare and life threatening complication of intracranial surgical procedures, and requires immediate recognition and surgical intervention. Tension pneumocephalus following ventriculoperitoneal shunt surgery is extremely rare and commonly seen as a delayed complication. To our knowledge, early postoperative tension pneumocephalus after shunt surgery was reported only in one other publication. We present a case of acute tension pneumocephalus following ventriculoperitoneal shunt surgery for normal pressure hydrocephalus, which was managed well with close neurological follow-up and rapid surgical intervention. The use of the portable CT scanner in this case saved significant time, without the transport of the patient to the radiology unit, made early surgical intervention possible, and prevented morbidity and mortality. PMID:24101285

  9. Comparative study of two structures of shunt active filter suppressing particular harmonics

    NASA Astrophysics Data System (ADS)

    Benchaita, L.; Salem Nia, A.; Saadate, S.

    1998-07-01

    This paper deals with the study of shunt active filters used for suppressing particular harmonics generated by nonlinear loads in utility distribution power systems. Both structures of shunt active filter, voltage source active filter (VSAF) and current source active filter (CSAF), are considered. The analytical study of specific harmonics identification in a given spectrum is first presented. For simulation as well as experimentation the nonlinear load is a conventional three phase thyristor rectifier and harmonics 5 and 7 are selected to be eliminated by active filter. The whole system consisting of the ac power supply network, the SCR rectifier and the shunt active filter (VSAF/CSAF) is then simulated. The simulation results are discussed and the efficiency of the two kinds of active filter are compared. Finally, for the first structure, VSAF, the simulation results are confirmed by experimental test realized by means of a fully digital control active power filter developed in our laboratory.

  10. Delayed-onset endophthalmitis associated with Ex-PRESS mini glaucoma shunt®.

    PubMed

    Ahmed, Yasir; Pathengay, Avinash; Flynn, Harry W; Isom, Ryan

    2012-01-01

    The authors describe a 92-year-old man who developed delayed-onset endophthalmitis secondary to Bacillus sp. in his left eye 3 years after placement of an Ex-PRESS mini glaucoma shunt (Optonol Ltd., Neve Ilan, Israel). Seidel testing was positive over the Ex-PRESS mini glaucoma shunt. The patient underwent vitreous tap followed by intravitreal injections of vancomycin (1 mg/0.1 mL), ceftazadime (2.25 mg/0.1 mL), and dexamethasone (0.4 mg/0.1 mL), along with subconjunctival injection of vancomycin and tobramycin. The last recorded visual acuity was 3/200 in the left eye. With a 1-month follow-up, this case illustrates successful treatment with a vitreous tap and injection of intravitreal antibiotics. Vitrectomy and removal of the Ex-PRESS mini glaucoma shunt were not performed. PMID:22785601

  11. A 100 GHz Josephson mixer using resistively-shunted Nb tunnel junctions

    NASA Technical Reports Server (NTRS)

    Schoelkopf, R. J.; Phillips, T. G.; Zmuidzinas, J.

    1993-01-01

    The authors describe preliminary mixer results using resistively shunted Nb/AlO(x)/Nb tunnel junctions in a 100-GHz waveguide mixer mount. The mixer utilizes robust, lithographically defined devices which have nonhysteretic I-V curves. A receiver temperature of 390 K (DSB) has been obtained with a conversion loss of -6.5 dB. The receiver's behavior agrees qualitatively with the behavior predicted by the resistively shunted junction model. Substantial improvements in performance are expected with the use of better-optimized shunted junctions, and numerical simulations suggest that, if devices with higher ICRN (critical current-normal state resistance) products can be obtained, Josephson effect mixers could be competitive with SIS mixers at high frequencies.

  12. Pseudotumor cerebri in a child receiving peritoneal dialysis: recovery of vision after lumbo-pleural shunt

    PubMed Central

    Alrifai, Muhammad Talal; Al Naji, Foad; Alamir, Abdulrahman; Russell, Neville

    2011-01-01

    A 9-year-old boy with end-stage renal disease who was receiving continuous ambulatory peritoneal dialysis (CAPD) presented with acute visual loss and was found to have papilledema. Neuroimaging and cerebrospinal fluid (CSF) analysis were normal. The lumbar puncture opening pressure was 290 mm of water so the diagnosis of pseudotumor cerebri (PTC) was entertained. Medical treatment was not an option because of renal insufficiency; neither was lumbo-peritoneal shunting, because of the peritoneal dialysis. After a lumbo-pleural shunt was placed, there was marked improvement in symptoms. The lumbo-pleural shunt is a reasonable option for treatment for PTC in patients on CAPD who require a CSF divergence procedure. PMID:21911996

  13. Superiority of radionuclide over oximetric measurement of left to right shunts.

    PubMed Central

    Baker, E J; Ellam, S V; Lorber, A; Jones, O D; Tynan, M J; Maisey, M N

    1985-01-01

    In 100 children with suspected left to right shunts the ratio of pulmonary to systemic flow was measured both by oximetry and first pass radionuclide angiography. The pulmonary time activity curve from the radionuclide study was analysed by the method of gamma variate fits. There was strong correlation between the two techniques; weaker correlation was found when the shunt was at atrial rather than ventricular level. This difference can be explained only by problems with the oximetric rather than the radionuclide technique. Although there are important limitations to the radionuclide method, it is the more precise and less invasive of the two and is to be preferred when the accurate measurement of left to right shunts is required. PMID:3994867

  14. Orthodeoxia-platypnea due to intracardiac shunting--relief with transcatheter double umbrella closure.

    PubMed

    Landzberg, M J; Sloss, L J; Faherty, C E; Morrison, B J; Bittl, J A; Bridges, N D; Casale, P N; Keane, J F; Lock, J E

    1995-11-01

    The safety and efficacy of transcatheter clamshell occlusion of patent foramen ovale for relief of severe arterial desaturation and dyspnea in the upright position due to intracardiac shunting were examined in eight patients with excessive risk of surgical patent foramen ovale closure. All patients had successful reduction of intracardiac shunting with an immediate rise in oxygen saturation > or = 95% by implantation of a clamshell device on the atrial septum. Despite two early incidents of device embolization, retrieval and immediate re-implantation, and one patient with nonsustained atrial and ventricular arrhythmias, there were no adverse clinical sequelae. In follow-up evaluation transcatheter clamshell closure of patent foramen ovale has provided persistent relief from shunt-related arterial desaturation and symptomatology in all living patients. PMID:8542634

  15. Wave propagation in beams with anti-symmetric piezoelectric shunting arrays

    NASA Astrophysics Data System (ADS)

    Sheng-Bing, Chen; Gang, Wang

    2016-03-01

    Piezoelectric shunting arrays are employed to control the wave propagation in flexible beams. Contrary to conventional symmetric configuration, a substrate beam with anti-symmetric shunting arrays is investigated by adapted transfer matrix method. Compared with symmetric scheme, the anti-symmetric one demonstrates some distinctive characteristics. Primarily, the longitudinal and flexural waves are coupled, so they are correlated and must be considered simultaneously. Moreover, the attenuation of flexural wave is much stronger in anti-symmetric scenario, while the longitudinal wave demonstrates the converse side. As a result, the anti-symmetric scheme can be utilized to improve the vibration isolation capability of shunting arrays. Finally, the theoretical analyses are validated by finite element simulations. Project supported by the National Natural Science Foundation of China (Grant No. 51322502).

  16. Cerebral venous thrombosis complicated by hemorrhagic infarction secondary to ventriculoperitoneal shunting.

    PubMed

    Son, Won-Soo; Park, Jaechan

    2010-10-01

    While a delayed intracerebral hemorrhage at the site of a ventricular catheter has occasionally been reported in literature, a delayed hemorrhage caused by venous infarction secondary to ventriculoperitoneal shunting has not been previously reported. In the present case, a 68-year-old woman underwent ventriculoperitoneal shunting through a frontal burr hole, and developed a hemorrhagic transformation of venous infarction on the second postoperative day. This massive venous infarction was caused by bipolar coagulation and occlusion of a large paramedian cortical vein in association with atresia of the rostral superior sagittal sinus. Thus, to eliminate the risk of postoperative venous infarction, technical precautions to avoid damaging surface vessels in a burr hole are required under loupe magnification in ventriculoperitoneal shunting. PMID:21113365

  17. A Shunt Model of the Inner Medullary Nephron with Pre-Bend Transitions

    NASA Astrophysics Data System (ADS)

    Gonzalez, M. T.; Hegarty, A. F.; Thomas, S. R.

    2009-09-01

    Mathematical models of the renal medulla face the problem of representing water and solute transfer among tens of thousands of nephrons and blood vessels of various lengths, arranged in countercurrent fashion. Published models fall into two broad categories with respect to this issue: multi-nephron models, which explicitly represent a large number of individual nephrons, or lumped models with virtual shunts that represent the turning back of nephrons and vessels at varying depths. Shunt models have the advantage of a compact description and relatively rapid execution time but are ill-suited to faithfully represent features such as prebend transitions of epithelial permeabilities in nephrons of different lengths. A new shunt model approach that can accommodate pre-bend transitions of nephrons at all medullary depths is presented in this work together with the results of simulation of predicted flows and concentrations.

  18. A mathematical model of diffusional shunting of oxygen from arteries to veins in the kidney.

    PubMed

    Gardiner, Bruce S; Smith, David W; O'Connor, Paul M; Evans, Roger G

    2011-06-01

    To understand how arterial-to-venous (AV) oxygen shunting influences kidney oxygenation, a mathematical model of oxygen transport in the renal cortex was created. The model consists of a multiscale hierarchy of 11 countercurrent systems representing the various branch levels of the cortical vasculature. At each level, equations describing the reactive-advection-diffusion of oxygen are solved. Factors critical in renal oxygen transport incorporated into the model include the parallel geometry of arteries and veins and their respective sizes, variation in blood velocity in each vessel, oxygen transport (along the vessels, between the vessels and between vessel and parenchyma), nonlinear binding of oxygen to hemoglobin, and the consumption of oxygen by renal tissue. The model is calibrated using published measurements of cortical vascular geometry and microvascular Po(2). The model predicts that AV oxygen shunting is quantitatively significant and estimates how much kidney Vo(2) must change, in the face of altered renal blood flow, to maintain cortical tissue Po(2) at a stable level. It is demonstrated that oxygen shunting increases as renal Vo(2) or arterial Po(2) increases. Oxygen shunting also increases as renal blood flow is reduced within the physiological range or during mild hemodilution. In severe ischemia or anemia, or when kidney Vo(2) increases, AV oxygen shunting in proximal vascular elements may reduce the oxygen content of blood destined for the medullary circulation, thereby exacerbating the development of tissue hypoxia. That is, cortical ischemia could cause medullary hypoxia even when medullary perfusion is maintained. Cortical AV oxygen shunting limits the change in oxygen delivery to cortical tissue and stabilizes tissue Po(2) when arterial Po(2) changes, but renders the cortex and perhaps also the medulla susceptible to hypoxia when oxygen delivery falls or consumption increases. PMID:21367922

  19. Deconvolution analysis in radionuclide quantitation of left-to-right cardiac shunts.

    PubMed

    Alderson, P O; Douglass, K H; Mendenhall, K G; Guadiani, V A; Watson, D C; Links, J M; Wagner, H N

    1979-06-01

    A poor bolus injection results in an unsatisfactory quantitative radionuclide angiocardiogram in as many as 20% of children with possible, left-to-right (L-R) cardiac shunts. Deconvolution analysis was applied to similar studies in experimental animals to determine whether dependence on the input bolus could be minimized. Repeated good-bolus, prolonged (greater than 2.5 sec), or multiple-peak injections were made in four normal dogs and seven dogs with surgically created atrial septal defects (ASD). QP/QS was determined using the gamma function. The mean QP/QS from ten good-bolus studies in each animal was used as the standard for comparison. In five trials in normal animals, where a prolonged or double-peak bolus led to a shunt calculation (QP/QS greater than 1.2 : 1), deconvolution resulted in QP/QS = 1.0. Deconvolution improved shunt quantitation in eight of ten trials in animals that received a prolonged bolus. The correlation between the reference QP/QS and the QP/QS calculated from uncorrected bad bolus studies was only 0.39 (p greater than 0.20). After deconvolution using a low pass filter, the correlation improved significantly (r = 0.77, p less than 0.01). The technique gave inconsistent results with multiple-peak bolus injections. Deconvolution analysis in these studies is useful in preventing normals from being classified as shunts, and in improving shunt quantitation after a prolonged bolus. Clinical testing of this technique in children with suspected L-R shunts seems warranted. PMID:536823

  20. Cross-sectional imaging of thoracic and abdominal complications of cerebrospinal fluid shunt catheters.

    PubMed

    Bolster, Ferdia; Fardanesh, Reza; Morgan, Tara; Katz, Douglas S; Daly, Barry

    2016-04-01

    This study aims to review the imaging findings of distal (thoracic and abdominal) complications related to ventriculo-peritoneal (VP), ventriculo-pleural (VPL), and ventriculo-atrial (VA) cerebrospinal fluid (CSF) shunt catheter placement. Institution review board-approved single-center study of patients with thoracic and abdominal CSF catheter-related complications on cross-sectional imaging examinations over a 14-year period was performed. Clinical presentation, patient demographics, prior medical history, and subsequent surgical treatment were recorded. The presence or absence of CSF catheter-related infection and/or acute hydrocephalus on cross-sectional imaging was also recorded. There were 81 distal CSF catheter-related complications identified on 47 thoracic or abdominal imaging examinations in 30 patients (age 5-80 years, mean 39.3 years), most often on CT (CT = 42, MRI = 1, US = 4). Complications included 38 intraperitoneal and 11 extraperitoneal fluid collections. Extraperitoneal collections included nine abdominal wall subcutaneous (SC) pseudocysts associated with shunt migration and obesity, an intrapleural pseudocyst, and a breast pseudocyst. There were also two large VPL-related pleural effusions, a fractured catheter in the SC tissues, and a large VA shunt thrombus within the right atrium. Ten patients (33.3 %) had culture-positive infection from CSF or shunt catheter samples. Ten patients (33.3 %) had features of temporally related acute or worsening hydrocephalus on neuroimaging. In four of these patients, the detection of thoracic and abdominal complications on CT preceded and predicted the findings of acute hydrocephalus on cranial imaging. Thoracic and abdominal complications of CSF shunts, as can be identified on CT,  include shunt infection and/or obstruction, may be both multiple and recurrent, and may be predictive of concurrent acute intracranial problems. PMID:26610766

  1. Electrospun polyurethane as an alternative ventricular catheter and in vitro model of shunt obstruction

    PubMed Central

    Suresh, Supraja

    2015-01-01

    Intracranial pressure and volume vary considerably between hydrocephalic patients, and with age, health and haemodynamic status; if left untreated, intracranial pressure rises and the ventricular system expands to accommodate the excess cerebrospinal fluid, with significant morbidity and mortality. Cerebrospinal fluid shunts in use today have a high incidence of failure with shunt obstruction being the most serious. Conventional proximal shunt catheters are made from poly(dimethyl)siloxane, the walls of which are perforated with holes for the cerebrospinal fluid to pass through. The limited range of catheters, in terms of material selection and flow distribution, is responsible in large part for their poor performance. In this study, we present an alternative design of proximal catheter made of electrospun polyether urethane, and evaluate its performance in the presence of glial cells, which are responsible for shunt blockage. The viability and growth of cells on catheter materials such as poly(dimethyl)siloxane and polyurethane in the form of cast films, microfibrous mats and porous sponges were studied in the presence of proteins present in cerebrospinal fluid after 48 h and 96 h in culture. The numbers of viable cells on each substrate were comparable to untreated poly(dimethyl)siloxane, both in the presence and absence of serum proteins found in cerebrospinal fluid. A cell culture model of shunt obstruction was developed in which cells on electrospun polyether urethane catheters were subjected to flow during culture in vitro, and the degree of obstruction quantified in terms of hydraulic permeability after static and perfusion culture. The results indicate that a catheter made of electrospun polyether urethane would be able to maintain cerebrospinal fluid flow even with the presence of cells for the time period chosen for this study. These findings have implications for the design and deployment of microporous shunt catheter systems for the treatment of

  2. Electrospun polyurethane as an alternative ventricular catheter and in vitro model of shunt obstruction.

    PubMed

    Suresh, Supraja; Black, Richard A

    2015-02-01

    Intracranial pressure and volume vary considerably between hydrocephalic patients, and with age, health and haemodynamic status; if left untreated, intracranial pressure rises and the ventricular system expands to accommodate the excess cerebrospinal fluid, with significant morbidity and mortality. Cerebrospinal fluid shunts in use today have a high incidence of failure with shunt obstruction being the most serious. Conventional proximal shunt catheters are made from poly(dimethyl)siloxane, the walls of which are perforated with holes for the cerebrospinal fluid to pass through. The limited range of catheters, in terms of material selection and flow distribution, is responsible in large part for their poor performance. In this study, we present an alternative design of proximal catheter made of electrospun polyether urethane, and evaluate its performance in the presence of glial cells, which are responsible for shunt blockage. The viability and growth of cells on catheter materials such as poly(dimethyl)siloxane and polyurethane in the form of cast films, microfibrous mats and porous sponges were studied in the presence of proteins present in cerebrospinal fluid after 48 h and 96 h in culture. The numbers of viable cells on each substrate were comparable to untreated poly(dimethyl)siloxane, both in the presence and absence of serum proteins found in cerebrospinal fluid. A cell culture model of shunt obstruction was developed in which cells on electrospun polyether urethane catheters were subjected to flow during culture in vitro, and the degree of obstruction quantified in terms of hydraulic permeability after static and perfusion culture. The results indicate that a catheter made of electrospun polyether urethane would be able to maintain cerebrospinal fluid flow even with the presence of cells for the time period chosen for this study. These findings have implications for the design and deployment of microporous shunt catheter systems for the treatment of

  3. Robust glycogen shunt activity in astrocytes: Effects of glutamatergic and adrenergic agents.

    PubMed

    Walls, A B; Heimbürger, C M; Bouman, S D; Schousboe, A; Waagepetersen, H S

    2009-01-12

    The significance and functional roles of glycogen shunt activity in the brain are largely unknown. It represents the fraction of metabolized glucose that passes through glycogen molecules prior to entering the glycolytic pathway. The present study was aimed at elucidating this pathway in cultured astrocytes from mouse exposed to agents such as a high [K+], D-aspartate and norepinephrine (NE) known to affect energy metabolism in response to neurotransmission. Glycogen shunt activity was assessed employing [1,6-13C]glucose, and the glycogen phosphorylase inhibitor 1,4-dideoxy-1,4-imino-D-arabinitol (DAB) to block glycogen degradation. The label intensity in lactate, reflecting glycolytic activity, was determined by mass spectrometry. In the presence of NE a substantial glycogen shunt activity was observed, accounting for almost 40% of overall glucose metabolism. Moreover, when no metabolic stimulant was applied, a compensatory increase in glycolytic activity was seen when the shunt was inhibited by DAB. Actually the labeling in lactate exceeded that obtained when glycolysis and glycogen shunt both were operational, i.e. supercompensation. A similar phenomenon was seen when astrocytes were exposed to D-aspartate. In addition to glycolysis, tricarboxylic acid (TCA) cycle activity was monitored, analyzing labeling by mass spectrometry in glutamate which equilibrates with alpha-ketoglutarate. Both an elevated [K+] and D-aspartate induced an increased TCA cycle activity, which was altered when glycogen degradation was inhibited. Thus, the present study provides evidence that manipulation of glycogen metabolism affects both glycolysis and TCA cycle metabolism. Altogether, the results reveal a highly complex interaction between glycogenolysis and glycolysis, with the glycogen shunt playing a significant role in astrocytic energy metabolism. PMID:19000744

  4. Occam's razor in the management of ventriculoperitoneal shunt dysfunction: Diagnosis and management of an unusual pediatric case.

    PubMed

    Dadlani, Ravi; Dadlani, Reena; Ghosal, Nandita; Hegde, Alangar

    2015-01-01

    Ventriculoperitoneal (VP) shunt surgery is probably the commonest surgical procedure in neurosurgery. Belying its technical simplicity is the myriad complications associated with it. Shunt malfunction is a common complication associated with this surgery, second only to shunt related infections, which may be associated with it. Sterile cerebrospinal fluid (CSF) eosinophilia (CE) has been reported with VP shunts, which may or may not be related to the dysfunction. Eosinophilia in the CSF has also been associated with a number of other conditions including parasitic infestations in the brain. This may be unrelated to the shunt surgery. We present a case of a child, operated earlier for hydrocephalus, who presented with sub-acute loss of vision and bilateral oculomotor paresis. CSF from a chamber tap revealed eosinophilia. The commonest presenting symptom of shunt malfunction is raised intracranial pressure. There are no reports in the literature of VP shunt malfunction presenting with bilateral oculomotor paresis and decreased visual acuity. The associated CE complicated the clinical picture, especially since the initial brain radiology was normal. We discuss the clinical differential diagnosis of this very interesting presentation, management dilemmas and outcome in this child. This rare clinical presentation was found to be the result of a shunt malfunction and not due to any rare parasitic infestation of the brain. Occam's razor dictates that the simplest explanation in a given situation is usually the most accurate, as is seen in this case. PMID:25972962

  5. Subcutaneous tumor growth complicating the positioning of Denver shunt and intrapleural port-à-cath in mesothelioma patients.

    PubMed

    van Ooijen, B; Eggermont, A M; Wiggers, T

    1992-12-01

    Patients with malignant ascites and malignant pleural fluid from abdominal or pleural mesothelioma underwent the positioning of Denver type peritoneovenous shunt or intrapleural catheter. They developed tumor growth in the subcutaneous tissue surrounding the devices throughout their courses. Neoplastic seeding is a potential complication of the positioning of shunts and catheters in cavities filled with fluid rich in tumor cells. PMID:1478300

  6. Semi-active control of piezoelectric coating's underwater sound absorption by combining design of the shunt impedances

    NASA Astrophysics Data System (ADS)

    Sun, Yang; Li, Zhaohui; Huang, Aigen; Li, Qihu

    2015-10-01

    Piezoelectric shunt damping technology has been applied in the field of underwater sound absorption in recent years. In order to achieve broadband echo reduction, semi-active control of sound absorption of multi-layered piezoelectric coating by shunt damping is significant. In this paper, a practical method is proposed to control the underwater sound absorption coefficients of piezoelectric coating layers by combining design of the shunt impedance that allows certain sound absorption coefficients at setting frequencies. A one-dimensional electro-acoustic model of the piezoelectric coating and the backing is established based on the Mason equivalent circuit theory. First, the shunt impedance of the coating is derived under the constraint of sound absorption coefficient at one frequency. Then, taking the 1-3 piezoelectric composite coating as an example, the sound absorption properties of the coating shunted to the designed shunt impedance are investigated. Next, on the basis of that, an iterative method for two constrained frequencies and an optimizing algorithm for multiple constrained frequencies are provided for combining design of the shunt impedances. At last, an experimental sample with four piezoelectric material layers is manufactured, of which the sound absorption coefficients are measured in an impedance tube. The experimental results show good agreement with the finite element simulation results. It is proved that a serial R-L circuit can control the peak frequency, maximum and bandwidth of the sound absorption coefficient and the combining R-L circuits shunted to multiple layers can control the sound absorption coefficients at multiple frequencies.

  7. Method of removing the effects of electrical shorts and shunts created during the fabrication process of a solar cell

    DOEpatents

    Nostrand, Gerald E.; Hanak, Joseph J.

    1979-01-01

    A method of removing the effects of electrical shorts and shunts created during the fabrication process and improving the performance of a solar cell with a thick film cermet electrode opposite to the incident surface by applying a reverse bias voltage of sufficient magnitude to burn out the electrical shorts and shunts but less than the break down voltage of the solar cell.

  8. Percutaneous Punctured Transcatheter Device Closure of Residual Shunt after Ventricular Septal Defect Repair

    PubMed Central

    2016-01-01

    Ventricular septal defects (VSDs) are estimated to account for 20 to 30% of all congenital heart defects (CHDs). Although a residual shunt is the most common complication of VSD surgery, a second operation that applies the surgical repair method is very difficult because it can increase the possibility of uncontrolled bleeding and the severity of tissue adhesion. Here, we present the first case of percutaneous punctured transcatheter device closure of a residual shunt after VSD repair as a novel method to further develop for the treatment of children with congenital heart disease. PMID:27293910

  9. Palliative ventriculoperitoneal shunt in a pediatric patient with recurrent metastatic medulloblastoma.

    PubMed

    Schiff, Deborah; Kline, Cassie; Meltzer, Hal; Auger, JoAnne

    2009-04-01

    The authors present a case report of a pediatric patient with recurrent metastatic medulloblastoma who demonstrated significant clinical improvement after placement of a palliative ventriculoperitoneal (VP) shunt. They also review the medical literature that supports palliative surgical management of hydrocephalus and intracranial hypertension (ICH) caused by leptomeningeal (LM) spread of malignancy. The burdens and benefits of an invasive surgical procedure must always be weighed carefully, especially at end-of-life. Yet for some patients with LM spread and ICH, VP shunting may improve their quality of life, although their prognosis remains poor. PMID:19327082

  10. Posterior Reversible Encephalopathy Syndrome and Subarachnoid Hemorrhage After Lumboperitoneal Shunt for Fulminant Idiopathic Intracranial Hypertension.

    PubMed

    Fok, Anthony; Chandra, Ronil V; Gutman, Matthew; Ligtermoet, Matthew; Seneviratne, Udaya; Kempster, Peter

    2016-06-01

    A 33-year-old woman presented with severe visual loss from fulminant idiopathic intracranial hypertension. Her lumbar puncture opening pressure was 97 cm H2O. Soon after lumboperitoneal shunt surgery, she had a generalized tonic-clonic seizure. Magnetic resonance imaging demonstrated frontal subarachnoid hemorrhage (SAH) and neuroimaging findings consistent with posterior reversible encephalopathy syndrome (PRES). We hypothesize that an abrupt drop in intracranial pressure after lumboperitoneal shunting led to maladjustment of cerebral vascular autoregulation, which caused SAH and PRES. PMID:26919070

  11. How a left-to-right shunt may protect against haemodynamic deterioration in restrictive cardiomyopathy.

    PubMed

    Van Mieghem, Nicolas; Daenen, Wim; Budts, Werner

    2005-06-01

    Today, more and more children with complex heart lesions and underlying cardiomyopathies reach adulthood. This results in a wide range of new clinical problems encountered in later life. In particular, idiopathic restrictive cardiomyopathy is initially treated by medication to reduce symptoms, but at end-stage disease, heart or heart-lung transplantation becomes unavoidable. We describe the case of a patient with restrictive cardiomyopathy and a persistent extra-cardiac left-to-right shunt, where we hypothesize that the shunt may protect against haemodynamic deterioration in end-stage restrictive cardiomyopathie. PMID:15999476

  12. Implementation of FFT Algorithm using DSP TMS320F28335 for Shunt Active Power Filter

    NASA Astrophysics Data System (ADS)

    Patel, Pinkal Jashvantbhai; Patel, Rajesh M.; Patel, Vinod

    2016-07-01

    This work presents simulation, analysis and experimental verification of Fast Fourier Transform (FFT) algorithm for shunt active power filter based on three-level inverter. Different types of filters can be used for elimination of harmonics in the power system. In this work, FFT algorithm for reference current generation is discussed. FFT control algorithm is verified using PSIM simulation results with DLL block and C-code. Simulation results are compared with experimental results for FFT algorithm using DSP TMS320F28335 for shunt active power filter application.

  13. Meso-Rex shunt for immediate portal revascularization in pediatric liver transplantation: first report.

    PubMed

    Rivera, Jairo; Fusaro, Fabio; de Magnée, Catherine; Clapuyt, Philippe; Reding, Raymond

    2012-09-01

    We describe the case of a 13-month-old girl transplanted for biliary atresia with PV hypoplasia. She received the left liver lobe of her mother and presented intraoperative portal thrombosis. Because of technical reasons, the opportunity to have conventional PV reconstruction using the donor left PV stump was lost. Immediate conversion to a meso-Rex shunt, using the recipient jugular vein as a bridge between the superior mesenteric vein and the graft Rex recessus, allowed excellent portal revascularization of the transplant. We suggest that synchronous meso-Rex shunt may constitute a valid alternative to truncal PV anastomosis during pediatric LT. PMID:21923884

  14. A new method for palliation of malignant obstructive jaundice utilizing a peritoneo-venous shunt pump.

    PubMed

    Araki, K; Kure, M; Kobayasi, M; Sugito, M; Ogata, T

    1994-02-01

    A new simple palliative method for use in malignant obstructive jaundice is presented. This method is particularly effective in the prevention of ascending infections. The method consists of interposing a one-way flow shunt pump (peritoneo-venous shunt pump) between a bile catheter and a jejunal catheter. Four patients were treated with this new method. Jaundice improved significantly in all patients. They had a much better quality of life with no serious complications during the terminal course. This less invasive and safe procedure is preferred for patients who have extrahepatic biliary obstruction due to incurable malignant tumors. PMID:7513676

  15. Temporary axillary-carotid shunting for unusual instances of carotid stenosis.

    PubMed

    Shumacker, H B; Isch, J H; Jolly, W W

    1976-07-01

    A method has been developed which entails the introduction of the larger end of a Javid shunt tube in the axillary artery and the other in the internal carotid with only momentary interruption of blood flow. The method of closing the incision after the thromboendarterectomy almost entirely eliminates a second period of carotid occlusion. This procedure may be useful in unusual instances in which it is believed advantageous to avoid even the relatively short occlusion periods usually necessary when using the standard intraluminal shunt technique. PMID:936041

  16. Cavo-pulmonary shunt: from the first experiments to clinical practice.

    PubMed

    Konstantinov, I E; Alexi-Meskishvili, V V

    1999-09-01

    The cavo-pulmonary anastomosis is often referred to as Glenn shunt today. The concept of cavo-pulmonary shunting, however, was developed independently by many surgeons. While the work of some of them is widely recognized, the pioneering contributions of many others fall into oblivion. Nonetheless, each of them contributed something original and precious to the total sum of our modern knowledge. It seems timely, as we enter the new millennium, to give due credit to those individuals who put their minds and efforts into helping sick children. These people deserve recognition. PMID:10510029

  17. Performance of organics and nitrogen removal in subsurface wastewater infiltration systems by intermittent aeration and shunt distributing wastewater.

    PubMed

    Pan, Jing; Yuan, Fang; Yu, Long; Huang, Linli; Fei, Hexin; Cheng, Fan; Zhang, Qi

    2016-07-01

    Organics and nitrogen removal in four subsurface wastewater infiltration systems (SWISs), named SWIS A (without intermittent aeration and shunt distributing wastewater), SWIS B (with intermittent aeration), SWIS C (with shunt distributing wastewater) and SWIS D (with intermittent aeration and shunt distributing wastewater) was investigated. High average removal rates of 92.3% for COD, 90.2% for NH4-N and 88.1% for TN were achieved simultaneously in SWIS D compared with SWIS A, B and C. The excellent TN removal of SWIS D was due to intermittent aeration provided sufficient oxygen for nitrification in upper matrix and the favorable anoxic or anaerobic environment for denitrification in subsequent matrix, and moreover, shunt distributing wastewater provided sufficient carbon source for denitrification process. The results indicated that intermittent artificial aeration combined with shunt distributing wastewater could achieve high organics and nitrogen removal in SWISs. PMID:27039353

  18. Histologic changes in previously irradiated thyroid glands

    SciTech Connect

    Valdiserri, R.O.; Borochovitz, D.

    1980-03-01

    Thyroid tissue from 90 patients with a history of therapeutic irradiation to the head and neck in childhood and adolescence was examined microscopically. In addition to the well-known observation that these individuals have an increased incidence of primary thyroid carcinoma, it was also demonstrated that they have an increased incidence of benign histologic changes. These changes represent a spectrum from nonspecific hyperplastic lesions to benign neoplasis and thyroidltis.

  19. Porcine deltacoronavirus: histological lesions and genetic characterization.

    PubMed

    Wang, Leyi; Hayes, Jeff; Sarver, Craig; Byrum, Beverly; Zhang, Yan

    2016-01-01

    First identified in 2012 in a surveillance study in Hong Kong, porcine deltacoronavirus (PDCoV) is a proposed member of the genus Deltacoronavirus of the family Coronaviridae. In February of 2014, PDCoV was detected in pigs with clinical diarrheal symptoms for the first time in the USA. Since then, it has been detected in more than 20 states in the USA and in other countries, including Canada, South Korea, and mainland China. So far, histological lesions in the intestines of pigs naturally infected with PDCoV under field conditions have not been reported. In this report, we describe the characteristic histological lesions in the small intestine that were associated with PDCoV infection, as evidenced by detection of viral nucleic acid by RT-PCR. In addition, we performed genomic analysis to determine the genetic relationship of all PDCoV strains from the four countries. We found that PDCoV mainly caused histological lesions in the small intestines of naturally infected piglets. Sequence analysis demonstrated that the PDCoV strains of different countries are closely related and shared high nucleotide sequence similarity; however, deletion patterns in the spike and 3' untranslated regions are different among the strains from mainland China, Hong Kong, the USA, and South Korea. Our study highlights the fact that continual surveillance is needed to trace the evolution of this virus. PMID:26475155

  20. The histological nature of epulides in dogs.

    PubMed

    Verstraete, F J; Ligthelm, A J; Weber, A

    1992-02-01

    The histological characteristics of a series of 154 oral tumours with the clinical appearance of epulides in 129 dogs were reviewed. Diagnoses were based on current criteria in human oral pathology and compared with the original diagnoses. The histological findings suggested that the majority of epulides in the dog can be classified as focal fibrous hyperplasia (43.5 per cent), peripheral ameloblastoma (17.5 per cent), peripheral odontogenic fibroma (WHO type) (16.9 per cent) and pyogenic granuloma (1.95 per cent). In addition, a number of other odontogenic tumours (1.95 per cent) and non-odontogenic tumours (18.2 per cent) such as fibrosarcoma and squamous cell carcinoma, which are not traditionally associated with the clinical appearance of an epulis, were diagnosed. Of 74 lesions that were previously diagnosed as fibromatous and ossifying epulides, 50 (68 per cent) were reclassified as focal fibrous hyperplasia and 21 (28 per cent) as peripheral odontogenic fibroma (WHO type). The majority of lesions (76 per cent), which were originally classified as acanthomatous epulis, were found to be peripheral ameloblastoma. In addition, three squamous cell carcinomas, two rare odontogenic tumours and two cases of focal fibrous hyperplasia were diagnosed in this classification. It was concluded that, as in man, the term epulis is a clinically descriptive term and that the renal nature of these lesions should be determined histologically. PMID:1597534