Lymphoepithelial Carcinoma of the Nasolacrimal Duct: Clinical, Radiologic, and Immunopathologic Features.

PubMed

Jakobiec, Frederick A; Stagner, Anna M; Rubin, Peter A D

Undifferentiated lymphoepithelial carcinoma (exhibiting both begin lymphoid and malignant epithelial components) most commonly arises in the head and neck, especially in the nasopharynx. It may also be encountered in various ocular adnexal sites, including the nasolacrimal duct. A 63-year-old woman developed a swelling in the region of the right lacrimal sac accompanied by epiphora. CT scanning revealed an enlargement of the nasolacrimal duct from the lacrimal sac to the inferior nasal meatus. A biopsy during dacryocystorhinostomy for symptomatic epiphora revealed hypercellular sheets of small lymphocytes which were interpreted as evidence for a chronic dacryocystitis. Two years later the subtotally excised lesion had substantially grown in size. Repeat CT scans demonstrated an inferonasal anterior orbital mass with further enlargement of the nasolacrimal duct with a solid mass in its lumen, and bone erosion. The biopsy combined a rich background of lymphocytes within which were clusters of undifferentiated carcinoma cells that were cytokeratin and p63 positive. Critical review of the earlier biopsy led to the detection of the same cells, but in smaller numbers, that had been overlooked. An awareness of the possibility of lymphoepithelial carcinoma of the lacrimal sac/duct should improve diagnostic accuracy with the aid of immunohistochemistry. Radiation therapy is often successful in managing this highly sensitive malignant tumor.

Changes in cytokines in tears after endoscopic endonasal dacryocystorhinostomy for primary acquired nasolacrimal duct obstruction.

PubMed

Lee, J K; Kim, T H

2014-05-01

We attempted to compare the cytokine composition of tears between primary acquired nasolacrimal duct (NLD) obstruction and normal controls. We investigated the changes in cytokines in tears after endoscopic endonasal dacryocystorhinostomy (DCR). Eighteen patients underwent endonasal DCR, with seven patients undergoing bilateral DCR, resulting in twenty-five DCRs in total. Eleven contralateral un-operated eyes were used as normal controls. Silicone stents were removed 3 months after surgery. Tear samples were collected from all eyes before surgery, and at 1 month, 2 months, 3 months, and 4 months after surgery. The level of interleukin (IL)-1β, IL-2, IL-6, IL-10, transforming growth factor (TGF)-β2, fibroblast growth factor (FGF)-2, and vascular endothelial growth factor (VEGF) in the tears was measured. The concentrations of IL-2, IL-6, IL-10, VEGF, and FGF-2 were significantly higher in eyes with NLD obstruction than controls before surgery (P=0.006, 0.018, 0.002, 0.048, and 0.039, respectively). Most inflammatory cytokines (IL-1β, IL-2, IL-6, VEGF, and FGF-2) were higher in the tears of the DCR group compared with the controls during the postoperative follow-up, but then rapidly decreased to the level of the controls after removal of the silicone stent. The recurred eyes showed a higher level of TGF-β2 and FGF-2 in tears compared with the eyes that showed good surgical results (P<0.005 and <0.005, respectively). The tear levels of inflammatory cytokines were higher in eyes with NLD obstruction than controls. The changes in cytokine level during the postoperative period showed the importance of cytokine analysis in understanding wound healing after DCR.

Transcanalicular Diode Laser-assisted Dacryocystorhinostomy for the Treatment of Primary Acquired Nasolacrimal Duct Obstruction.

PubMed

Mor, Joel M; Guo, Yongwei; Koch, Konrad R; Heindl, Ludwig M

2017-10-13

Today's gold standard in the treatment of infrasaccal primary acquired nasolacrimal duct obstruction (PANDO) is external dacryocystorhinostomy (DCR), a relatively invasive procedure that can be performed after failure of recanalizing treatments. However, with progress in the field of diode laser technology, new approaches have emerged. Laser-assisted transcanalicular DCR with subsequent bicanalicular silicon intubation is a new option showing great promise as a viable minimally invasive procedure. Under permanent endoscopic visual control from the nasal cavity, a diode laser fiber is inserted into the lacrimal sac and laser energy is applied to create a bony ostium between the lacrimal sac and the nasal cavity. Since no skin incision needs to be made, advantages of this method comprise the sparing of the skin as well as the medial palpebral structures and the physiological palpebral-canalicular pump mechanism. The duration of surgery as well as reconvalescence is generally shorter than with external DCR. Complications include silicon tube prolapse, mild swelling and, rarely, canalicular infection and thermal injury. One-year functional success rates, defined as complete resolution of symptoms and ostium patency, are high, yet still range behind those of external DCR. However, secondary external DCR after failure of laser-assisted DCR can be performed without difficulty. Thus, laser-assisted transcanalicular DCR is a valid option that should be considered as a second-step procedure after failure of recanalization procedures and before external DCR.

Morphometric Measurements of Bony Nasolacrimal Canal in Children.

PubMed

Ela, Araz Server; Cigdem, Kalaycik Ertugay; Karagoz, Yesim; Yigit, Ozgur; Longur, Ecem Sevim

2018-05-01

Morphology and dimensions of the bony nasolacrimal canal duct (BNLD) as a key factor in the development of primary acquired nasolacrimal duct obstruction. We aimed to obtain detailed morphometric analysis of BNLD in children without nasolacrimal duct pathology by using computed tomography and provide standard measurements by means of age which could be utilized in planning management or in invasive interventions. Picture Archiving Communication Systems database of our hospital's radiology department was searched for this retrospective study. Subjects were under 18 years of age who had undergone a paranasal, maxillofacial, or temporal bone high-resolution computed tomography scan in last 2 years with various indications. Those with fractures including facial bones and/or nasolacrimal canal or history of nasolacrimal duct pathology were excluded from the study. We measured the diameter, angle, and surface area of BNLD. A total number of 136 subjects (86 boys, 50 girls) were included in the study. The average age was 7.3 ± 5.1 years. We documented statistically significantly positive correlation between all measured diameters and ages (P < 0.001), whereas there was a negative association between mean angle and age (P < 0.001). Mean angle is defined as the angle between BNLD and nasal floor. The surface area of BNLD was found to be significantly increasing depending on age (P < 0.001). However, we could not find any significant association between gender and measured parameters (P > 0.050). Our study demonstrated that development of BNLD continues during childhood, regardless of gender.

Efficacy of probing for children with congenital nasolacrimal duct obstruction: a retrospective study using fluorescein dye disappearance test and lacrimal sac echography.

PubMed

Steindler, Piero; Mantovani, Enrico; Incorvaia, Carlo; Parmeggiani, Francesco

2009-06-01

To evaluate B-scan echography for the assessment of lacrimal sac (LS) in pediatric epiphora secondary to congenital nasolacrimal duct obstruction (CNLDO), and to verify its predictive role in functional efficacy of nasolacrimal duct probing. Thirty-nine eyes of 23 consecutive children, treated with a single probing for persistent CNLDO-related epiphora, were retrospectively studied. These cases were investigated both collectively and considering two sub-groups: group A (ten patients [20 eyes] 13 months. Fluorescein dye disappearance test at 10 minutes (FDDT-10) and ultrasound examination of LS were performed before and after probing. An echographic LS scoring system (grade 0 = no LS enlargement; grade 1 = slight longitudinal LS enlargement; grade 2 = longitudinal and slight transverse LS enlargement; grade 3 = marked longitudinal and transverse LS enlargement) was introduced as a predictor of probing efficacy, estimating FDDT-10 modification between pre- and post-operative checks. Echographic LS evaluation was easily practicable without sedation. In the total cluster and in both age sub-groups, post-probing FDDT-10 decreased with respect to pre-probing value (p < 0.001). Post-probing LS score improved with respect to pre-probing check within the total cluster and group A (p < 0.05). Strong correlation between pre-probing LS alteration and functional probing failure was present in each studied cluster (all p values <0.0001). Within group B, a greater gain of post-probing FDDT-10 was more frequent in patients with a better pre-probing LS score, as well as in younger children (both p values <0.0001). In children with CNLDO-related epiphora, B-scan echography of the LS can represent a reliable and useful examination for a better understanding of the functional prognosis after probing treatment.

A survey of management of congenital nasolacrimal duct obstruction by pediatric primary health care providers in Spain.

PubMed

Galindo-Ferreiro, Alicia; Palencia-Ercilla, Teresa; Ferreira, Livia Mendoza; Galvez-Ruiz, Alberto; Zornoff, Denise C M; Khandekar, Rajiv; Schellini, Silvana A

2017-06-26

To survey the management of congenital nasolacrimal duct obstruction (CNLDO) by pediatric primary health care providers in Spain. This was a descriptive study using a web-based questionnaire to evaluate the perceptions of the members of the Pediatric Primary Care Society in Castilla-León, Spain (APAPCYL), regarding management of CNLDO. The questionnaire contained 14 direct questions and was sent by e-mail to all the pediatricians. All the responses were analyzed by the frequency of occurrence and percentages. Ninety physicians responded to the questionnaire. Massage 2 or 3 times a day was the initial treatment advised by 60.47% of pediatricians. Nearly half of the pediatricians recommended continuing massage until symptoms resolved. Fewer than 50% of children required referral to an ophthalmologist. Reasons for an ophthalmic consult included persistence of symptoms among 87.21% of pediatricians and parental/guardian request among 10.5% of pediatricians. According to 45.6% of pediatricians, their knowledge about CNLDO is limited, and 92.2% would like to receive further training on CNLDO. Massage was the main initial treatment for managing CNLDO among pediatricians. The outcomes of this survey indicated that massage fails in fewer than 50% of patients and an ophthalmic referral is required for these cases.

Use of the Crawford tube for symptomatic epiphora without nasolacrimal obstruction.

PubMed

Tong, Nyu-Xia; Zhao, Ying-Ying; Jin, Xiu-Ming

2016-01-01

To evaluate the effectiveness of the Crawford tube in treating symptomatic epiphora without nasolacrimal obstruction. A protocol was adopted for the management of symptomatic epiphora without nasolacrimal obstruction. Patients who suffered symptomatic epiphora without nasolacrimal obstruction in both eyes were included in the study. One eye was treated with Crawford tube intubation and the other eye was treated with medication therapy. Degree of watering, patient satisfaction, and symptomatic improvement were carefully evaluated by one of the authors at the end of the follow-up period, after Crawford tube removal, to ascertain functional results. Thirty-seven adult patients (37 eyes) underwent Crawford tube intubation for functional epiphora. The mean follow-up time after removal of the tube was 14.8±4.8mo. The procedure was an overall success in 28 eyes (75.7%), with symptoms improving significantly. Two eyes (5.4%) were relieved of indoor epiphora, two (5.4%) had minimal epiphora outdoors, but only with wind or cold, and five (13.5%) continued to experience tearing both indoors and outdoors. Thirty of the patients (81%) expressed satisfaction with the procedure. Crawford tube insertion is an effective, safe, simple, and relatively noninvasive treatment strategy for functional lacrimal system obstruction.

Transection of Nasolacrimal Duct in Endoscopic Medial Maxillectomy: Implication on Epiphora.

PubMed

Imre, Abdulkadir; Imre, Seher Saritepe; Pinar, Ercan; Ozkul, Yilmaz; Songu, Murat; Ece, Ahmet Ata; Aladag, Ibrahim

2015-10-01

Management of the nasolacrimal system is usually recommended during medial maxillectomy via external approach because of reported higher rates of postoperative epiphora. Association of the endoscopic medial maxillectomy (EMM) with epiphora, however, is not clearly stated. In this study, we attempted to evaluate whether patients develop epiphora after simple transection of the nasolacrimal duct during EMM. Medical records of 26 patients who underwent endoscopic tumor resection for inverted papilloma (IP) were retrospectively reviewed. Patients who underwent EMM with nasolacrimal canal transection were included and recalled for lacrimal system evaluation. Twelve patients were eligible for inclusion and fluorescein dye disappearance test (FDDT) was performed for each patient. Patient demographics, tumor data, surgical procedures, and follow-up time were recorded. Of the 12 patients included in the study, 6 underwent canine fossa transantral approach concurrently with EMM. The mean duration of follow-up was 21.1 months (range, 6-84 months). Eight patients were graded as 0, whereas 4 patients were graded as 1 according to FDDT. All test results were interpreted as negative for epiphora. All patients were completely symptom free of epiphora. Epiphora after EMM with nasolacrimal canal transection among patients with sinonasal tumors appears to be uncommon. Therefore, prophylactic concurrent management of nasolacrimal system including stenting, dacryocystorhinostomy (DCR), or postoperative lacrimal lavage are not mandatory for all patients.

Microbiology of primary acquired nasolacrimal duct obstruction: simple epiphora, acute dacryocystitis, and chronic dacryocystitis

PubMed Central

Pornpanich, Kanograt; Luemsamran, Panitee; Leelaporn, Amornrut; Santisuk, Jiraporn; Tesavibul, Nattaporn; Lertsuwanroj, Buntitar; Vangveeravong, Sumalee

2016-01-01

Purpose The aim of this study was to determine the microbiology of primary acquired nasolacrimal duct obstruction (PANDO) and its antimicrobial susceptibilities. Methods Ninety-three patients (100 eyes) diagnosed with PANDO, categorized as acute, chronic dacryocystitis, or simple epiphora, were prospectively enrolled. Lacrimal sac contents were cultured for aerobic and anaerobic bacteria and fungi. Cultured organisms were identified, and antimicrobial susceptibility testing was performed for aerobic bacteria. Results Seventy-nine of the 100 samples were culture positive. One hundred twenty-seven organisms were isolated, and 29 different species were identified. Most microorganisms were Gram-positive bacteria (45 samples or 57.0% of all positive culture samples), whereas Gram-negative bacteria, anaerobic bacteria, and fungi were found in 39 (49.4%), 24 (30.4%), and four samples (5.1%), respectively. The most frequently isolated group was coagulase-negative staphylococci (27.8%), followed by nonspore-forming Gram-positive rods (anaerobe) (17.7%) and Pseudomonas aeruginosa (15.2%). Of the 100 samples, five, 45, and 50 samples were obtained from patients with acute dacryocystitis, chronic dacryocystitis, and simple epiphora, respectively. Subgroup analysis showed that Gram-negative organisms were isolated more frequently from the chronic dacryocystitis subgroup than from the simple epiphora subgroup (P=0.012). Antimicrobial susceptibility testing demonstrated that ciprofloxacin was the most effective drug against all Gram-positive and Gram-negative organisms. Conclusion Patients with PANDO, with or without clinical signs of lacrimal infection, were culture positive. Gram-negative organisms were frequently isolated, which were different from previous studies. Ciprofloxacin was the most effective agent against all Gram-positive and Gram-negative organisms. PMID:26955261

Nasolacrimal duct obstruction following radioactive iodine 131 therapy in differentiated thyroid cancers: review of 19 cases.

PubMed

Al-Qahtani, Khalid Hussain; Al Asiri, Mushabbab; Tunio, Mutahir A; Aljohani, Naji J; Bayoumi, Yasser; Munir, Iqbal; AlAyoubi, Ayman

2014-01-01

Radioactive iodine 131 ((131)I) therapy has long been used in the treatment of differentiated thyroid cancers (DTC). While salivary and lacrimal glandular complications secondary to (131)I therapy are well documented, there is little in the literature addressing nasolacrimal duct obstruction (NLDO). We aimed to evaluate the frequency of (131)I therapy-acquired NLDO, its correlation to (131)I therapy doses, and the surgical treatment outcome of this rare side effect. From 2000-2012, a retrospective review of 864 among 1,192 patients with confirmed DTC who were treated with (131)I therapy was performed to examine the frequency of NLDO, its causative factors, as well as imaging, surgical intervention, and outcomes. Nineteen (2.2%) patients were identified with NLDO. The mean age was 51.9±10.5 years (range: 39-72 years). Fifteen (78.9%) were female and four were male (21.1%). The mean individual (131)I doses were 311.1±169.3 millicurie (mCi) (range: 150-600 mCi). The mean duration between the date of (131)I therapy and the occurrence of NLDO was 11.6±4.1 months (range: 6.5-20). Fourteen (73.7%) patients had bilateral epiphora. Computed tomography dacryography allowed for the detection of all NLDO. Eighteen (94.7%) patients underwent dacryocystorhinostomy. Complete recovery was obtained in 14 (73.7%) patients. Age >45 years and (131)I therapy doses >150 mCi were significantly correlated with NLDO (P=0.02 and P=0.03, respectively). NLDO is an underestimated complication of (131)I therapy in DTC patients. Clinicians should be aware of this rare complication for prompt intervention.

Comparison of endoscopic and external dacryocystorhinostomy for treatment of primary acquired nasolacrimal duct obstruction

PubMed Central

Su, Pei-Yuan

2018-01-01

PURPOSE: The purpose of this study is to compare the success rates of endoscopic endonasal dacryocystorhinostomy (EN-DCR) and external DCR (EX-DCR) for the treatment of primary acquired nasolacrimal duct obstruction (PANLDO). DESIGN: This was a retrospective, comparative, nonrandomized clinical study. METHODS: Reviewed medical records of PANLDO underwent DCR at Far-Eastern Memorial Hospital from May 2011 to June 2017. Data regarding the lacrimal passage system, comorbidities, surgical outcomes, and postoperative complications were analyzed. Anatomical success was defined as patency confirmed by intranasal endoscopic inspection of the ostium and successful lacrimal irrigation; functional success was defined as complete resolution of epiphora and positive fluorescein dye disappearance test, which were assessed at postoperative 6th months. RESULTS: One hundred and seventy patients (37 males, 133 females, mean age 57 years) underwent 178 DCR surgeries for PANLDO. The overall anatomical success rate was 94.4% (93.5% in EN-DCR vs. 95.8% in EX-DCR, P = 0.511) and functional success rate was 90.4% (90.7% in EN-DCR and 90.1% in EX-DCR, P = 0.909). Surgical outcomes were comparable between two groups. Complication rate was low in both groups, including 11 cases of early canalicular stent dislodge (7 in EN-DCR, 4 in EX-DCR), one case of postoperative nasal bleeding in EN-DCR, and two skin wound dehiscence and three cutaneous keloid formation in EX-DCR. None of these cases were concluded into surgical failure at the final visit. The time to symptoms relief was statistical significantly shorter in EN-DCR group (1.7 vs. 3.7 weeks in EX-DCR, P < 0.001). CONCLUSIONS: Success rate of DCR for PANLDO in our study was high, and complication rate was low for both endoscopic and external approaches. There was no statistically significant difference between them. EN-DCR provided higher satisfaction due to quicker recovery and lack of external incision. Endoscopic DCR should be considered

The natural process of congenital nasolacrimal duct obstruction and effect of lacrimal sac massage.

PubMed

Karti, Omer; Karahan, Eyyup; Acan, Durgul; Kusbeci, Tuncay

2016-12-01

This study aimed to examine the rate of symptomatic improvement of congenital nasolacrimal duct obstruction (CNLDO) in infants treated with conservative management within the first year of age. Other purpose of the study is to emphasize the relationship between spontaneous resolution time and effective lacrimal sac massage. Thirty-one infants were diagnosed to have CNLDO by an ophthalmologist prior to 3 months of age. In this study, 36 eyes of 31 patients were included with CNLDO. The patients were divided into two groups. Group 1 (28 eyes of 24 patients) was consisted of the patients who were applied effective lacrimal sac massage regularly during the follow-up period, and patients whose parents did not apply a regular lacrimal passage regularly were accepted as group 2 (8 eyes of 7 patients). Thirty-three eyes of 31 patients (18 rights and 15 left) successfully resolved with only conservative management (91.6 %). In these thirty-three eyes, one eye (3 %) resolved between 0 and 3 months, fourteen eyes (42.5 %) resolved between 4 and 6 months, eleven eyes (33.3 %) resolved between 7 and 9 months, and seven eyes (21.2 %) resolved between 10 and 12 months. CNLDO was resolved in 27 (96.2 %) of 28 eyes in group 1, and in group 2, six eyes (77.7 %) had resolvement. This difference was statistically significant (p = 0.001). The mean age of resolution was 6.8 ± 1.88 months in group 1, 10.3 ± 1.5 months in group 2 (p < 0.001). In light of our study, we believe that conservative management of CNLDO is highly successful. Our study provided a possible objective explanation for the efficacy of lacrimal sac massage. Emphasizing the importance of the massage to parents and describing in detail can reduce the risk of unnecessary surgical interventions.

Minimally invasive medial maxillectomy and the position of nasolacrimal duct: the CT study.

PubMed

Sieskiewicz, Andrzej; Buczko, Krzysztof; Janica, Jacek; Lukasiewicz, Adam; Lebkowska, Urszula; Piszczatowski, Bartosz; Olszewska, Ewa

2017-03-01

Several minimally invasive modifications of endoscopic medial maxillectomy have been proposed recently, with the least traumatic techniques utilizing the lacrimal recess as a route to enter the sinus. The aim of the study was to analyze the anatomy of medial maxillary wall in the region of nasolacrimal canal and, thus, to determine the capability of performing minimally invasive approach to the maxillary sinus leading through the lacrimal recess. The course of nasolacrimal canal and the distance between the anterior maxillary wall and the nasolacrimal canal (the width of lacrimal recess) were evaluated in 125 randomly selected computed tomography (CT) head examinations. The proportion of cases with unfavorable anatomical conditions (lacrimal recess too narrow to accept a 4 mm optic) to perform minimally invasive middle maxillectomy was assessed. The width of lacrimal recess, measured at the level of the inferior turbinate attachment, varied between 0 and 15.2 mm and was related to slanted course of nasolacrimal canal. The more perpendicular the axis of the canal to the nasal flor, the narrower the lacrimal recess. In about 16% of cases, lacrimal recess width was less than 4 mm and in 14.4% it was missing. The endoscopic approach to maxillary sinus leading through lacrimal recess is possible in about 70% of patients. In the remaining group of patients when the lacrimal recess is too narrow, this type of approach may be difficult to perform without damaging the piriform aperture rim or bony framework of nasolacrimal duct, or it may be impracticable when lacrimal recess is missing.

Change in quality of life of patients undergoing silicone stent intubation for nasolacrimal duct stenosis combined with dry eye syndrome.

PubMed

Oh, Jong Rok; Chang, Jee Ho; Yoon, Jin Sook; Jang, Sun Young

2015-11-01

To investigate the effect of silicone stent intubation (SI) on the quality of life of patients diagnosed with nasolacrimal duct stenosis and dry eye syndrome. This study is a prospective, interventional case series. Consecutive 30 patients diagnosed with nasolacrimal duct stenosis and reflex tearing due to dry eye syndrome were included. Eligible subjects underwent SI and were asked to complete the Glasgow Benefit Inventory (GBI) questionnaire. Surgical outcomes and GBI scores were investigated 6 months postoperatively. The surgical success rate determined by the patients' subjective symptoms was 76.7% (23/30). Mean total GBI score was +17.19 (95% CI 8.34 to 26.03). The general subscale score was +20.36 (95% CI 10.19 to 30.54), the social support scale score was +21.54 (95% CI 11.37 to 31.71) and the physical health score was -0.56 (95% CI -8.92 to 7.80). SI could be an effective treatment option for reflex tearing in patients diagnosed with dry eye syndrome and nasolacrimal duct stenosis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

THE INCIDENCE OF SYMPTOMATIC ACQUIRED LACRIMAL OUTFLOW OBSTRUCTION AMONG RESIDENTS OF OLMSTED COUNTY, MINNESOTA, 1976–2000 (AN AMERICAN OPHTHALMOLOGICAL SOCIETY THESIS)

PubMed Central

J., John; Woog

2007-01-01

Purpose To define the incidence, clinical characteristics, and outcomes following treatment of symptomatic acquired lacrimal outflow obstruction (SALOO) in Olmsted County, Minnesota, from 1976 to 2000, and to test the hypothesis that the incidence of this disorder increased over this interval. Methods In this retrospective, population-based study, the Rochester Epidemiology Project was used to identify patients above the age of 5 years with SALOO. Patient medical records were reviewed, and the incidence and localization of lacrimal obstruction were determined. Results Five-hundred eighty-seven patients with SALOO were identified, with an average annual incidence rate of 30.47 per 100,000. Nasolacrimal duct obstruction was most common, with an incidence of 20.24 per 100,000. The increase in incidence from 1976–1979 to 1996–2000 was statistically significant (P=.01). Among 397 patients with nasolacrimal duct obstruction, 107 (27%) were male and 290 (73%) female, with a mean age of 59.5 ± 22 years. SALOO and nasolacrimal duct obstruction incidence increased with age. Glaucoma, dry eye, cataract, diabetes mellitus, systemic malignancy, cigarette smoking, and hypertension were noted in 5.5%, 8.7%, 37.5%, 10.9%, 18.5%, 26.4%, and 41.1% of patients, respectively. One hundred eleven patients underwent dacryocystorhinostomy, with a success rate of 94.1%. Conclusions SALOO incidence increased during the study interval, although a possible plateau effect was noted during the last 5 years of the study period. The majority of patients were female above the age of 66 years. The latter finding, in conjunction with US demographic trends, suggests that the frequency of SALOO may continue to increase in the future. External dacryocystorhinostomy appeared to be effective in the management of nasolacrimal duct obstruction. PMID:18427633

Tear-Duct Obstruction and Surgery

MedlinePlus

... Staying Safe Videos for Educators Search English Español Tear-Duct Obstruction and Surgery KidsHealth / For Parents / Tear- ... year old with little or no treatment. About Tear Ducts Our eyes are continually exposed to dust, ...

Positive predictive value of cholescintigraphy in common bile duct obstruction

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

Lecklitner, M.L.; Austin, A.R.; Benedetto, A.R.

1986-09-01

Technetium-99m DISIDA imaging was employed in 400 patients to differentiate obstruction of the common bile duct from medical and other surgical causes of hyperbilirubinemia. Sequential anterior images demonstrated variable degrees of liver uptake, yet there was no evidence of intrabiliary or extrabiliary radioactivity for at least 4 hr after injection in 25 patients. Twenty-three patients were surgically documented to have complete obstruction of the common bile duct. One patient had hepatitis, and another had sickle cell crisis without bile duct obstruction. The remaining patients had either partial or no obstruction of the common bile duct. We conclude that the presencemore » of liver uptake without evident biliary excretion by 4 hr on cholescintigraphy is highly sensitive and predictive of total obstruction of the common bile duct.« less

Blocked Tear Duct

MedlinePlus

... of the nose (lacrimal sac). From there tears travel down a duct (the nasolacrimal duct) draining into your nose. Once in the nose, tears are reabsorbed. A blockage can occur at any point in the tear drainage system, from the puncta ...

Transitional cell neoplasm of the nasolacrimal duct associated with human papillomavirus type 11.

PubMed

Vickers, Jennifer L; Matherne, Ryan J; Allison, Ashley W; Wilkerson, Michael G; Tyring, Stephen K; Bartlett, Brenda L; Rady, Peter L; Kelly, Brent C

2010-07-01

Tumors of the lacrimal sac are rare but noteworthy because of their significant potential to become malignant or life-threatening if treatment is delayed. Dermatologists may be the first to encounter such neoplasms. We report a case of a 53-year-old Caucasian woman who presented with a seven-year history of an asymptomatic, subcutaneous nodule near her right medial canthus. Histology of the lesion revealed transitional epithelium in a papillary growth pattern with numerous goblet cells, scattered mitoses and focal full-thickness atypia. The patient was diagnosed with transitional cell neoplasm (inverted papilloma-type) of the nasolacrimal duct. PCR evaluation identified HPV type 11 in the lesion. Our report is one of a growing number of case reports and series detecting HPV DNA in these tumors which further supports HPV as an etiologic agent in epithelial lacrimal sac tumors. We believe that dermatopathologists need to be aware of this entity, as dermatologists may be the first to encounter these neoplasms. The association of HPV with this tumor does not prove causality.

Endoscopic endonasal dacryocystorhinostomy with ostial stent intubation following nasolacrimal duct stent incarceration.

PubMed

Wang, Xiaopeng; Bian, Yang; Yan, Wentao; Daniel, Pelaez; Tu, Yunhai; Wu, Wencan

2015-01-01

To study the feasibility of endoscopic endonasal dacryocystorhinostomy (EE-DCR) with novel lacrimal ostial stent (LOS) intubation for patients with chronic dacryocystitis with incarceration of a previously implanted nasolacrimal duct stent (NDS). According to surgical procedure, 166 patients (167 eyes) were divided into two groups: EE-DCR with LOS intubation was performed on 126 patients (127 eyes) in the EE-DCR group; while external dacryocystorhinostomy (E-DCR) with silicone tube intubation was performed on 40 patients (40 eyes) in the E-DCR group. The LOS or silicone tube was retained for 3-6 months. All patients were followed up for 12-36 months. Success rate of tear drainage reconstruction (TDR) and complications were retrospectively compared. Excluding patients with early detachment of the LOS or the silicone tube, or with incomplete follow-up period, 117 patients (117 eyes) in the EE-DCR group and 36 patients (36 eyes) in the E-DCR group were included. The mean surgical time was 45.8 ± 11.5 min in the EE-DCR group and 68.1 ± 23.8 min in the E-DCR group (p < 0.001). Intraoperatively, the lacrimal sac was observed to become very small and its walls were thin, hyperemic and fragile, firmly attaching to the NDS by fibrous bands in all eyes. Upon final review, success rate of TDR was 83.8% (98/117) in the EE-DCR group, while 58.3% (21/36) in the E-DCR group (p < 0.01). Failure of TDR due to ostial closure by excessive fibrosis occurred in 14 out of 19 patients in the EE-DCR group, significantly less than the 11 out of 15 patients with failed TDR in the E-DCR group (χ(2 )= 6.959, p < 0.01). No significant difference existed in failures due to granuloma occluding the ostium or common canaliculus obstruction. EE-DCR with LOS intubation may be an effective procedure to manage the special subgroup of patients with chronic dacryocystitis with incarcerations of a previously implanted NDS.

Endoscopic-modified medial maxillectomy and its limitation for a solitary fibrous tumor of the lacrimal sac and nasolacrimal duct.

PubMed

Moriyama, Munehito; Kodama, Satoru; Hirano, Takashi; Suzuki, Masashi

2017-06-01

Solitary fibrous tumor (SFT) is an uncommon neoplasm that usually arises from the pleura. Recently, SFTs have been reported in the head and neck region located in subsites such as the orbit. SFTs of the lacrimal sac are extremely rare, with only six cases reported in the English literature. We describe a SFT arising from the right lacrimal sac and extending along the nasolacrimal duct into the nasal cavity. Although, the tumor could not be removed by endoscopic-modified medial maxillectomy (EMMM) alone, combined approach with EMMM and a small external incision achieved the complete removal of the tumor. The patient has remained disease-free 24 months after surgery. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

New tapered metallic stent for unresectable malignant hilar bile duct obstruction.

PubMed

Sakai, Yuji; Tsuyuguchi, Toshio; Nishikawa, Takao; Sugiyama, Harutoshi; Sasaki, Reina; Sakamoto, Dai; Watanabe, Yuto; Nakamura, Masato; Yasui, Shin; Mikata, Rintaro; Yokosuka, Osamu

2015-10-16

To examine the usefulness of a new tapered metallic stent (MS) in patients with unresectable malignant hilar bile duct obstruction. This new tapered MS was placed in 11 patients with Bismuth II or severer unresectable malignant hilar bile duct obstruction, as a prospective study. The subjects were six patients with bile duct carcinoma, three with gallbladder cancer, and two with metastatic bile duct obstruction. Stenosis morphology was Bismuth II: 7, IIIa: 3, and IV: 1. UMIN Clinical Trial Registry (UMIN000004758). MS placement was 100% (11/11) successful. There were no procedural accidents. The mean patency period was 208.401 d, the median survival period was 142.000 d, and the mean survival period was 193.273 d. Occlusion rate was 36.4% (4/11); the causes of occlusion were ingrowth and overgrowth in 2 patients each, 18.2%, respectively. Patients with occlusion underwent endoscopic treatment one more time and all were treatable. The tapered MS proved useful in patients with unresectable malignant hilar bile duct obstruction because it provided a long patency period, enabled re-treatment by re-intervention, and no procedural accidents occurred.

Small intestinal obstruction by remnants of the omphalomesenteric duct: findings on contrast enema.

PubMed

Fenton, L Z; Buonomo, C; Share, J C; Chung, T

2000-03-01

We reviewed the contrast enema examinations and medical records of six patients with small intestinal obstruction due to omphalomesenteric duct remnant to evaluate for characteristic imaging findings. In five out of the six patients the point of obstruction was demonstrated on the enema; in three patients, the characteristic "beak" of a volvulus was seen, either in the terminal ileum or cecum. In three patients, there was medial deviation of the cecum. The characteristic radiographic features of volvulus at the cecum or terminal ileum and medial deviation of the cecum should suggest persistence of an omphalomesenteric duct remnant as the etiology of obstruction in a child less than 2 years of age. The appearance of omphalomesenteric duct remnant obstruction on enema examination, though not specific, is characteristic and should be familiar to pediatric radiologists.

Vision-related quality of life in patients undergoing silicone tube intubation for lacrimal passage obstructions.

PubMed

Kabata, Yoshiaki; Goto, Satoshi; Takahashi, Genichiro; Tsuneoka, Hiroshi

2011-07-01

To evaluate the changes in vision-related quality of life in patients with lacrimal passage obstructions undergoing silicone tube intubations. Prospective, consecutive, comparative, interventional case series. Forty-five patients with the chief complaint of epiphora diagnosed with complete and unilateral lacrimal passage obstructions were enrolled. Exclusion criteria included history of congenital nasolacrimal stenosis; lacrimal passage obstructions resulting from trauma, tumor, or chemotherapy; previous lacrimal passage surgery; and partial and functional nasolacrimal duct obstructions. Silicone tube intubation using a Nunchaku-style tube was performed under direct visualization with dacryoendoscope in all patients. Operations were considered as successful when the irrigating fluid could pass through the lacrimal passage and the disappearance of dye was observed in dye disappearance test and the patients' epiphora symptoms improved 3 months postoperatively. The 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) was self-administered in all patients preoperatively and 3 months postoperatively. Patients' preoperative and 3-months-postoperative NEI VFQ-25 scores were compared. Operations were successful in 40 patients (89%). Fully completed questionnaires were received from 32 patients (80%). Silicone tube intubation using a Nunchaku-style tube was associated with a significant improvement of the NEI VFQ-25 composite score (P = .0001), ocular pain score (P < .0001), and mental health score (P = .0003). Relief of epiphora by silicone tube intubation using a Nunchaku-style tube treatment significantly improved the vision-related quality of life in patients with lacrimal passage obstructions. Copyright © 2011 Elsevier Inc. All rights reserved.

Intubation of the ostium and nasolacrimal duct with a single self-linking silicone stent in external dacryocystorhinostomy.

PubMed

Hui, Jennifer I; Shriver, Erin M; Tse, David T

2011-01-01

To describe a stent placement method that eliminates stent prolapse in external dacryocystorhinostomy. A retrospective, institutional review board- approved case series of patients undergoing external dacryocystorhinostomy with an alternative stenting method. Following anastomosis of the posterior flaps, one arm of a Crawford silicone stent is passed through each canaliculus. Both arms are then passed through the nasolacrimal duct and retrieved in the inferior meatus. The 2 distal arms are redirected in the nose; one arm is looped around the proximal portions within the lacrimal sac and tied to the second arm. The stent is self-linked around the inferior turbinate. Nine patients underwent external dacryocystorhinostomy with alternative stenting. None experienced postoperative stent prolapse. At last follow-up (average, 38 months; range, 5-102 months), 8 patients reported resolution of tearing and exhibited normal dye clearance. On compression of the lacrimal sac, none of these 8 patients exhibited reflux of stagnant tears or dye through the canaliculi. This alternative method improves stent retention by using the inferior turbinate as a stopper to eliminate stent prolapse. The self-linking nature obviates the need and expense of additional biomedical devices.

Octreotide inhibits hepatic fibrosis, bile duct proliferation and bacterial translocation in obstructive jaundice.

PubMed

Türkçapar, Nuran; Bayar, Sancar; Koyuncu, Ayhan; Ceyhan, Koray

2003-01-01

The protective effect of octreotide on bacterial translocation, bile duct epithelial proliferation and hepatic fibrosis was studied in an experimental obstructive jaundice model. Forty-five healthy Wistar albino rats were randomly divided into three groups. Group I (n = 15): Median laparotomy and common bile duct manipulation performed (Sham group). Group II (n = 15): Laparotomy and common bile duct ligation performed. Group III (n = 15): After laparotomy and common bile duct ligation octreotide (Sandostatin, sandoz) was given. Simultaneously group I and II received 3 cc 0.9% NaCl and group III received 20 micrograms/kg/daily octreotide subcutaneously every 8 hours during 9 days. Two days after the procedure all rats were opened under ether anesthesia and sterile conditions. Group I had simple laparotomy but group II and III also had common bile duct ligation by 5/0 prolene. Seven days after the surgery (9th day after treatment) all rats underwent laparotomy and tests for bacterial translocation, liver biochemical tests and histopathologic analysis of liver and small bowel were carried out. In group II cecal population levels of bacteria were significantly higher than group I and group III (p < 0.05). In group II there was also statistically significant bacterial translocation to the mesenteric lymph nodes. Pathological changes were found in terminal ileum samples in group II which seemed to improve in group III. Hepatocyte function was preserved with octreotide treatment which also significantly decreased bile duct proliferation and periportal fibrosis in response to biliary obstruction. This experimental study showed that octreotide is effective in preventing bacterial translocation, bile duct proliferation and hepatic fibrosis in obstructive jaundice.

Acute dacryocystitis associated with epstein-barr virus infection.

PubMed

Ghauri, Abdul-Jabbar; Keane, Pearse A; Scotcher, Stephen M; Clarke, Jayne L; Madge, Simon N

2011-10-01

Acute dacryocystitis is a rare complication of infectious mononucleosis with only three previous reports in the English literature. We present two further children with acute dacryocystitis and clinical and laboratory features of Epstein-Barr Virus related infectious mononucleosis. Both were treated with systemic antibiotics and one child additionally required surgical drainage of a lacrimal sac abscess. Both children made a complete recovery without any lacrimal symptoms. Acute dacryocystitis is uncommon in children without a history of congenital nasolacrimal duct obstruction, and an underlying systemic condition such as infectious mononucleosis should be suspected. In such patients, dacryocystitis can be expected to resolve without symptoms of nasolacrimal duct obstruction and dacryocystorhinostomy is seldom required.

Extracorporeal shock wave lithotripsy for obstructing pancreatic duct calculi.

PubMed

Matthews, K; Correa, R J; Gibbons, R P; Weissman, R M; Kozarek, R A

1997-08-01

A review was done to determine the effectiveness of extracorporeal shock wave lithotripsy (ESWL) in the treatment of impacted pancreatic duct calculi. A total of 19 patients, who were potential candidates for radical pancreatic surgery after unsuccessful endoscopic retrograde cholangiopancreatography, sphincterotomy and attempted stone extraction from the pancreatic ducts, underwent ESWL of the calculi. Followup ranged from 6 months to 6 years. Of the 19 patients 14 avoided a major operation and 6 have remained pain-free for the long term. Two patients died of causes not related to ESWL or endoscopic retrograde cholangiopancreatography. Five patients eventually underwent a Whipple or Puestow procedure for relief of symptoms or persistent obstruction. Complications were minimal. ESWL is a valuable adjunct in patients with impacted pancreatic duct calculi unretrievable by primary endoscopic retrograde cholangiopancreatography.

Effects of Capsaicin and Carbachol on Secretion From Transplanted Submandibular Glands and Prevention of Duct Obstruction.

PubMed

Su, Jia-Zeng; Liu, Xiao-Jing; Wang, Yang; Cai, Zhi-Gang; Zhang, Lei; Lv, Lan; Wang, Zhen; Hong, Xia; Yu, Guang-Yan

2016-04-01

To investigate whether capsaicin and carbachol promote secretion from and prevent duct obstruction in transplanted submandibular glands (SMGs). This retrospective cohort study included consecutive patients with severe keratoconjunctivitis sicca and successful SMG transplantation. Patients were divided into 2 groups: an exposed group receiving both capsaicin and carbachol after surgery and an unexposed group receiving neither. Secretion changes in response to capsaicin and carbachol administration were recorded in the exposed group. The main outcome measures were the secretory flow rate and duct obstruction rate in the transplanted SMGs. Forty-four patients (44 eyes) in the unexposed group and 115 patients (128 eyes) in the exposed group were followed up for more than 3 months postoperatively. The baseline characteristics were similar between the groups. The secretory flow rate before and 5, 25, 55 minutes after administration was 1 mm (0-2 mm) (median with interquartile range), 3 mm (1-5 mm), 4 mm (2-5 mm), 1 mm (0-2.5 mm), respectively, for capsaicin and 1 mm (0-3 mm), 1050 mm (450-1500 mm), 375 mm (150-600 mm), 0 mm (0-150 mm), respectively, for carbachol (P < 0.001 for both). In the exposed group, 6.2% of eyes had duct obstruction, whereas 18.2% of eyes in the unexposed group had duct obstruction (P = 0.031) (odds ratio = 0.3, 95% confidence interval, 0.105-0.856). This study provides evidence that capsaicin and carbachol effectively promote secretion from and prevent duct obstruction in transplanted SMGs during at least 3 months after transplantation.

Hepatic fascioliasis presenting with bile duct obstruction: a case report.

PubMed

Lefryekh, Rachid; Bensaad, Ahmed; Bensardi, Fatimazahra; Elhattabi, Khalid; Bouali, Mounir; Daif, Bessam; Fadil, Abdelaziz; Jaouhari, Zakaria; Hicham, Tazi; Hamdani, Aziz; Abdalaoui, Maha Soussi

2017-01-01

Fascioliasis is a zoonotic infection caused by a liver trematode: fasciola hepatica; which commonly affects cattle and sheep, humans are accidental hosts. Several cases have been reported in the literature worldwide with a large geographical distribution. We present a case of bile duct obstruction due to a hepatic fascioliasis, successfully treated with both a combined surgical and medical approaches. A high index of suspicion should be kept in mind for all cases of obstructive jaundice, especially in areas in which human fascioliasis infection is repeatedly reported.

Hepatic fascioliasis presenting with bile duct obstruction: a case report

PubMed Central

Lefryekh, Rachid; Bensaad, Ahmed; Bensardi, Fatimazahra; Elhattabi, Khalid; Bouali, Mounir; Daif, Bessam; Fadil, Abdelaziz; Jaouhari, Zakaria; Hicham, Tazi; Hamdani, Aziz; Abdalaoui, Maha Soussi

2017-01-01

Fascioliasis is a zoonotic infection caused by a liver trematode: fasciola hepatica; which commonly affects cattle and sheep, humans are accidental hosts. Several cases have been reported in the literature worldwide with a large geographical distribution. We present a case of bile duct obstruction due to a hepatic fascioliasis, successfully treated with both a combined surgical and medical approaches. A high index of suspicion should be kept in mind for all cases of obstructive jaundice, especially in areas in which human fascioliasis infection is repeatedly reported. PMID:29158867

Successes rate of endoscopic dacryocystorhinostomy at KMC.

PubMed

Shrestha, S; Kafle, P K; Pokhrel, S; Maharjan, M; Toran, K C

2010-01-01

Nasolacrimal duct obstruction is a common problem which can be corrected by dacryocystorhinostomy (DCR). The gold standard treatment for this is DCR operation through an external approach. Development of endoscopic sinus surgery and endoscopic DCR performed through intranasal route is a major recent development in this field. The aim of this study is to find out the success rate of endoscopic dacryocystorhinostomy without silicon stent intubation within the period of six month following surgery. A prospective study was done on 26 patients with obstruction of the nasolacrimal duct referred from eye out-patient department to ENT OPD during one year period from 2008 to 2009. All the cases had undergone endoscopic DCR operation which was regularly followed up for a period of six months. Postoperative patency of ostium was checked by sac syringing and endoscopic visualisation of ostium in the nasal cavity. The success of surgery was categorised as: complete cure, partial cure and no improvement depending upon symptomatic relief and clinical examination such as sac syringing and endoscopic examination following surgery. In six months' follow-up, 22 (84.5%) out of 26 patients had achieved the complete cure and 4 patients (15.5%) continued to have persistent epiphora. Endoscopic DCR is a beneficial procedure for nasolacrimal duct obstruction with no external scar on face and less bleeding. The success rate is as good as external DCR.

[Qilin Pills for obstructive azoospermia after ejaculatory duct reconstruction].

PubMed

Zhang, Lei; Gao, Ping; Ren, Fei-Qiang; Chang, De-Gui; Yu, Xu-Jun; Zhang, Pei-Hai

2016-09-01

To observe the clinical effect of Qilin Pills in the treatment of severe oligozoospermia after microsurgical ejaculatory duct reconstruction for obstructive azoospermia. We retrospectively analyzed 75 cases of obstructive azoospermia treated by ejaculatory duct reconstruction followed by administration of Qilin Pills. The patients were divided into a Qilin group (n=42) and a control group (n=33) postoperatively, treated with Qilin Pills and placebo, respectively. After 3 months of medication, we compared the sperm quality between the two groups of patients. After 3 months' treatment, all the patients experienced remarkable improvement in sperm quality (P<0.05). Compared with the controls, the patients in the Qilin group showed dramatic increases in sperm concentration, from (0.57±0.25) and (0.60±0.18) ×10⁶/ml before medication to (2.83±0.59) and (1.72 ±0.52) ×10⁶/ml after medication, significantly higher in the Qilin than in the control group (P<0.05). The percentage of grade a sperm was increased from (5.52±5.97) and (5.30±6.26)% to (11.56±9.96) and (10.27±6.52)%, that of grade a+b sperm from (9.68±8.63) and (8.64±10.10)% to (23.42 ±14.10) and (20.81±14.70)%, and that of morphologically normal sperm from (2.00±1.27) and (2.31±0.94)% to (3.54±2.47) and (3.47±1.33)%, respectively. No statistically significant differences were observed in sperm motility and normal sperm morphology between the two groups after treatment (P>0.05). The total effectiveness rate was higher in the Qilin group than in the controls (88.1% vs 72.7%), but with no significant difference between the two groups (P>0.05). Qilin Pills are fairly effective in improving the quantity of sperm in obstructive azoospermia patients after ejaculatory duct reconstruction.

[Bile duct obstruction due to non-Hodkin's lymphoma in patients with HIV infection].

PubMed

Gómez-Domínguez, E; Rodríguez Serrano, D A; Mendoza, J; Iscar, T; Sarriá, C; García-Buey, L

2003-12-01

Acquired immune deficiency syndrome increases the risk of developing non-Hodgkin's B-cell lymphoma (NHL) (relative risk over 100). NHL tend to be high-grade and to affect the central nervous system and digestive tract. Biliary tract compression is usually due to external compression from enlarged lymph nodes, but is not usually the first manifestation.We describe 2 cases of bile duct obstruction secondary to NHL in patients diagnosed with HIV infection. Histological diagnosis of the lymphoma can be difficult but is necessary so that these patients do not undergo highly aggressive surgical treatment instead of chemotherapy, which currently produces the best results. Therefore, we emphasize the importance of including lymphomas in the differential diagnosis of bile duct obstruction in patients with HIV infection.

Clinical response to dorsal duct drainage via the minor papilla in refractory obstructing chronic calcific pancreatitis

PubMed Central

Kwon, Chang-Il; Gromski, Mark A.; Sherman, Stuart; El Hajj, Ihab I.; Easler, Jeffrey J.; Watkins, James; McHenry, Lee; Lehman, Glen A.; Fogel, Evan L.

2017-01-01

Background and study aims Complete stone removal from the main pancreatic duct might not be achieved in all patients with obstructive chronic calcific pancreatitis. We report our results for endoscopic dorsal pancreatic duct (DPD) bypass of obstructing stones in the ventral pancreatic duct (VPD). Patients and methods 16 patients with obstructive chronic calcific pancreatitis were treated with a DPD bypass. Clinical success was defined as significant pain relief and no hospital admissions for pain management during the ongoing treatment period. Results Among 16 patients meeting entry criteria, 10 (62.5%) had a history of unsuccessful endoscopic therapy, and 8 had failed extracorporeal shockwave lithotripsy (ESWL). Clinical success was achieved in 12 patients (75 %). Among these responders, 10 patients (83.3 %) had markedly improved or complete pain relief after the first stent placement, which persisted throughout the follow-up period; 11 patients (91.7 %) were able to discontinue their daily analgesics. Conclusions In selected patients with obstructive chronic calcific pancreatitis, the DPD bypass may be considered as a rescue endoscopic therapy, potentially obviating the need for surgery when standard endoscopic methods and ESWL fail. PMID:28201840

Obstructive parotitis from extraorally introduced foreign body in the Stensen duct.

PubMed

Levine, George; Clark, Matthew; Mandel, Louis

2013-12-01

A rare phenomenon, the extraoral traumatic penetration of a foreign body into the lumen of the parotid duct, is described. The ensuing obstructive symptomatology and its diagnostic approach and therapy are reviewed. Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

[Phytobezoar in the common hepatic duct - rare cause of obstructive jaundice following pancreatoduodenectomy: case report and review of the literature].

PubMed

Garlipp, B; Schulz, H-U; Böttcher, S; Lemke, A; Meyer, F; Lippert, H

2012-11-01

Obstruction of bile flow following pancreatoduodenectomy can be caused by stenosis of the hepaticojejunostomy created at the time of surgery, obstruction of the bile-draining jejunal loop, stones or, very rarely, ingested foreign bodies in the common hepatic duct. In analogy with endoscopic sphincterotomy or the once popular side-to-side-choledochduodenostomy, the creation of a hepaticojejunostomy eliminates the barrier of the sphincter Oddi, enabling intestinal content such as ingested foreign bodies or food fibers to migrate into the bile duct. We report on the case of a patient developing biliary tract obstruction due to fibrous material in the common hepatic duct 15 years after pancreatoduodenectomy. In addition, an overview of the literature on the rare phenomenon of foreign body-associated obstructive jaundice is given. © Georg Thieme Verlag KG Stuttgart · New York.

Analysis of 777 cases with obstruction of the ureter or extrahepatic bile duct by ultrasonography after normal saline retention enema

PubMed Central

2012-01-01

Background Conventional transabdominal ultrasound usually fails to visualize parts of the ureter or extrahepatic bile duct covered by bowel gas. In this study, we propose a new method for gaining acoustic access to the ureters and extrahepatic bile duct to help determine the nature of obstruction to these structures when conventional transabdominal ultrasound fails. Methods The normal saline retention enema method, that is, using normal saline-filled colons to gain acoustic access to the bilateral ureters and extrahepatic bile duct and detecting the lesions with transabdominal ultrasonic diagnostic apparatus, was applied to 777 patients with obstructive lesions, including 603 with hydroureter and 174 with dilated common bile duct, which were not visualized by conventional ultrasonography. The follow-up data of all the patients were collected to verify the results obtained by this method. Results Of the 755 patients who successfully finished the examination after normal saline retention enema (the success rate of the enema is about 98%), the nature of obstruction in 718 patients was determined (the visualizing rate is approximately 95%), including 533 with ureteral calculus, 23 with ureteral stricture, 129 with extrahepatic bile duct calculus, and 33 with common bile duct tumor. Conclusions Colons filled fully with normal saline can surely give acoustic access to the bilateral ureters and extrahepatic bile duct so as to determine the nature of obstruction of these structures when conventional transabdominal ultrasound fails. PMID:22871226

Intestinal obstruction caused by omphalomesenteric duct remnant: usefulness of laparoscopy.

PubMed

Bueno Lledó, J; Serralta Serra, A; Planeéis Roig, M; Dobón Giménez, F; Ibáñez Palacín, F; Rodero Rodero, R

2003-10-01

The anomalies related to omphalomesenteric duct remnant constitute an uncommon cause of intestinal obstruction, of which Meckel"s diverticulum and its variants represent the most important clinical presentation. In most cases they are asymptomatic and usually affect young patients. When symptomatic, they usually present episodes of gastrointestinal bleeding or acute abdomen syndromes caused by strangulation of intestinal loops as a result of fibrous intraabdominal remnants or inflammation produced by the diverticulum. In most cases, the unexpected presence of these alterations makes intraoperative diagnosis necessary. Treatment is surgical and consists in exeresis of the diverticulum or the fibrous band causing the clinical picture. We report two cases of persistence of the vitelline duct resolved by laparoscopic approach.

Efficacy of plastic stent placement inside bile ducts for the treatment of unresectable malignant hilar obstruction (with videos).

PubMed

Kaneko, Takashi; Sugimori, Kazuya; Shimizu, Yuro; Miwa, Haruo; Kameta, Eri; Koh, Ryonho; Numata, Kazushi; Tanaka, Katsuaki; Maeda, Shin

2014-05-01

Recent reports have addressed the utility of plastic stent (PS) placement inside bile ducts for treating biliary obstructions. Here, we evaluated the utility and safety of PS placement inside bile ducts for treating unresectable malignant hilar biliary obstruction. We conducted a retrospective study of 27 patients with unresectable malignant hilar biliary obstruction who underwent intraductal modified PS placement. We modified the PS, by cutting off the distal end to facilitate insertion through the papilla of Vater, and attached a nylon thread to the distal end for removal. We evaluated complications, the time to recurrent biliary obstruction (TRBO), and removability. Bilateral stenting was performed in nine of the 27 patients. Mild acute pancreatitis occurred in one patient (4%). Recurrent biliary obstruction (RBO) occurred in 16 patients (59%), with a median TRBO of 190 days (95% confidence interval: 174-205 days). Reintervention was necessary in 13 of the 16 patients (81%) with RBO, and we were able to remove the initial stents in all the patients who required reintervention. A relatively long stent patency period (>6 months) and removability make placement of a modified PS inside bile ducts a viable treatment for unresectable malignant hilar biliary obstruction. © 2013 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

Recovery of hepatic clearance and extraction following a release of common bile duct obstruction in the rat.

PubMed

Melzer, E; Krepel, Z; Ronen, I; Bar-Meir, S

1992-01-01

The rate of recovery for hepatic clearance and extraction following release of common-duct obstruction was investigated in the rat. Male Wistar rats underwent ligation of a cannulated common bile duct. Two weeks later, the cannula was opened and implanted into the duodenum, thus re-establishing enterohepatic circulation. Hepatic extraction and indocyanine green clearance were determined in three groups of six rats each, which differed by the time elapsed from the re-establishment of communication between the common bile duct and duodenum, i.e., 1, 48 and 168 h, respectively. A fourth group, in which a sham operation was performed, served as a control. Clearance was reduced from 16.9 +/- 2.5 ml/min per kg in the control group to 2.9 +/- 0.8, 5.4 +/- 2.4, and 8.5 +/- 3.3 ml/min per kg 1, 48, and 168 h, respectively, after release of common-bile-duct obstruction. Extraction rate was reduced from 37.3 +/- 5.9% to 17.5 +/- 2.7% in the 1st hour and recovered completely at 1 week. Thus, in the rat, release of a 2-week common-bile-duct obstruction is associated with complete recovery of the extraction capacity of the liver within a week, but only incomplete recovery of clearance. This decrease in clearance seems to be due to a decrease in effective hepatic blood flow, mostly probably due to the development of porto-systemic shunts.

Pediatric endocanalicular diode laser dacryocystorhinostomy: results of a minimally invasive surgical technique.

PubMed

Uysal, Ismail Onder; Ozçimen, Muammer; Yener, Halil Ibrahim; Kal, Ali

2011-09-01

The purpose of this study was to evaluate the effectiveness of endocanalicular diode laser dacryocystorhinostomy (DCR), which is a minimally invasive surgical technique, in pediatric patients with congenital nasolacrimal duct obstruction (NLDO). A retrospective study was carried out on patients treated between October 2008 and August 2009 for nasolacrimal duct obstruction with an endocanalicular diode laser procedure. Patients diagnosed as having nasolacrimal duct obstruction were included in this study and an endocanalicular diode laser procedure was performed. The main outcome measures were patients' previous treatments, clinical presentation, operative and postoperative complications, postoperative follow-up and resolution of epiphora. Eighteen children (10 girls, 8 boys) with a mean age of 6.11 ± 2.08 years (range, 4-10) underwent 20 endocanalicular laser DCR operations for congenital NLDO. In all eyes (100%), there was a history of epiphora and chronic dacryocystitis; two (10%) presented with acute dacryocystitis. Previous procedures included probing and irrigation of all eyes (100%) and silicone tube intubation in nine eyes (45%). None of the patients underwent any previous DCR operations. During a mean postoperative follow-up period of 20.50 ± 3.24 months (range, 14-24 months), the anatomical success rate (patency of ostium on nasal endoscopy) was 100%, and the clinical success rate (resolution of epiphora) was 85%. Endocanalicular diode laser DCR is an effective treatment modality for pediatric patients with congenital NLDO that compares favorably with the reported success rates of external and endoscopic endonasal DCR. Moreover, it has an added advantage of shorter operative time, less morbidity and avoidance of overnight admission.

Extrahepatic biliary duct obstruction as a result of involuntary transcavitary implantation of hair in a cat

PubMed Central

Linton, Michael; Buffa, Eugene; Simon, Adrian; Ashton, Julie; McGregor, Ross; Foster, Darren J

2015-01-01

Case summary A 4-year-old male neutered domestic shorthair cat was referred for investigation of jaundice. The cat had a recent history of a skin laceration repair following trauma. Sequential serum biochemistry demonstrated increasing plasma bilirubin concentrations; abdominal ultrasonography revealed ongoing pancreatitis and apparent extrahepatic obstruction of the common bile duct. Exploratory laparotomy identified constriction of the common bile duct with foreign material (cat hair). The constricting band of hair was removed surgically; cholecystoduodenostomy was performed. Postsurgical quality of life is excellent with chronic treatment of tylosin, omeprazole and ursodeoxycholic acid. Relevance and novel information To our knowledge, this is the first reported case of extrahepatic biliary duct obstruction resulting from the intra-abdominal migration of a foreign body, in this case, hair shafts. The mechanism by which this occurred was likely a combination of physical constriction by the hair shafts and subsequent foreign body reaction surrounding this. This should be included in the differential diagnosis of a cat with jaundice. PMID:28491390

Bilateral congenital lacrimal fistulas in an adult as part of ectrodactyly-ectodermal dysplasia-clefting syndrome: A rare anomaly.

PubMed

Ghosh, Debangshu; Saha, Somnath; Basu, Sumit Kumar

2015-10-01

Ectrodactyly-ectodermal dysplasia and clefting syndrome or "Lobster claw" deformity is a rare congenital anomaly that affects tissues of ectodermal and mesodermal origin. Nasolacrimal duct (NLD) obstruction with or without atresia of lacrimal passage is a common finding of such a syndrome. The authors report here even a rarer presentation of the syndrome which manifested as bilateral NLD obstruction and lacrimal fistula along with cleft lip and palate, syndactyly affecting all four limbs, mild mental retardation, otitis media, and sinusitis. Lacrimal duct obstruction and fistula were managed successfully with endoscopic dacryocystorhinostomy (DCR) which is a good alternative to lacrimal probing or open DCR in such a case.

Regulation of Epithelial Injury and Bile Duct Obstruction by NLRP3 and IL-1R1 in Experimental Biliary Atresia.

PubMed

Yang, Li; Mizuochi, Tatsuki; Shivakumar, Pranavkumar; Mourya, Reena; Luo, Zhenhua; Gutta, Sridevi; Bezerra, Jorge A

2018-06-07

Biliary atresia (BA) results from a neonatal inflammatory and fibrosing obstruction of bile ducts of unknown etiology. Although the innate immune system has been linked to virus-induced mechanism of disease, the role of the inflammasome-mediated epithelial injury remains largely undefined. Here, we hypothesized that disruption of the inflammasome suppresses the neonatal proinflammatory response and prevents experimental BA. We determined the expression of key inflammasome-related genes in livers from infants at diagnosis of BA and in extrahepatic bile ducts (EHBDs) of neonatal mice after infection with rotavirus (RRV) immediately after birth. Then, we determined the impact of the wholesale inactivation of the genes encoding IL-1R1 (Il1r1 -/- ), NLRP3 (Nlrp3 -/- ) or Caspase-1 (Casp1 -/- ) on epithelial injury and bile duct obstruction. IL1R1, NLRP3 and CASP1 mRNA increased significantly in human livers at the time of diagnosis, and in extrahepatic bile ducts of RRV-infected mice. In Il1r1 -/- mice, the epithelial injury of EHBDs induced by RRV was suppressed, with an inability of dendritic cells (DCs) to activate natural killer (NK) cells. A similar protection was observed in Nlrp3 -/- mice, with decreased injury and inflammation of livers and EHBDs. Long-term survival was also improved. In contrast, the inactivation of the Casp1 gene had no impact on tissue injury, and all mice died. Tissue analyses in Il1r1 -/- and Nlrp3 -/- mice showed decreased population of DC and NK cells and suppressed the expression of type-1 cytokines and chemokines. Inflammasome genes are overexpressed at diagnosis of BA in humans and in the BA mouse model. In the experimental model, the targeted loss of IL-1R1 or NLRP3, but not of Capase-1, protected neonatal mice against RRV-induced bile duct obstruction. Biliary atresia is a severe inflammatory and obstructive disease of bile ducts of infancy. Although the cause is unknown, an activation of the innate and adaptive immune systems injure

Graft versus host disease: what should the oculoplastic surgeon know?

PubMed

Tung, Cynthia I

2017-09-01

To provide a concise review of the oculoplastic manifestations of ocular graft versus host disease (GVHD), and to discuss their management. Ocular GVHD occurs as a common immune-mediated complication of hematopoietic stem cell transplantation that presents as a Stevens-Johnson-like syndrome in the acute phase or a Sjögren-like syndrome in the chronic phase. Cicatricial conjunctivitis may be underreported in ocular GVHD. The spectrum of oculoplastic manifestations includes GVHD of the skin, cicatricial entropion, nasolacrimal duct obstruction, and lacrimal gland dysfunction. Surgical treatment is indicated for patients with significant corneal complications from entropion. Surgical approach to repair of nasolacrimal duct obstruction is presented in this review, including modified approaches for treating patients at risk for keratitis sicca. Management of the ocular graft versus host patient may require a multidisciplinary approach involving collaboration from the oculoplastic surgeon, the corneal specialist, and the stem cell transplant physician. Oculoplastic manifestations of ocular GVHD typically present as cicatricial changes in the eyelid and lacrimal system. Careful oculoplastic and corneal evaluation are necessary when considering surgical management for the ocular GVHD patient.

Bile duct obstruction

MedlinePlus

... Tumors that have spread to the biliary system Liver and bile duct worms (flukes) The risk factors include: History of ... Increased bilirubin level Increased alkaline phosphatase level Increased liver enzymes The ... CT scan Endoscopic retrograde cholangiopancreatography ( ...

Using the phacoemulsification crescent knife in dacryocystorhinostomy.

PubMed

Fong, K S; Koh, A H; Choo, C T

1998-04-01

Dacryocystorhinostomy is an effective treatment for nasolacrimal duct obstruction. Most techniques employ a conventional blade or knife in making the incision of the nasal mucosa and lacrimal sac. The authors describe the use of a phacoemulsification crescent knife for this purpose. This technique can be effective and at the same time safer and easier to perform.

Epiphora associated with dacryops in a dog.

PubMed

Grahn, B H; Mason, R A

1995-01-01

A six-month-old basset hound was presented with unilateral right epiphora and medial canthal and maxillary bone swelling. Skull radiographs and dacryocystorhinography revealed a nasal cyst, right nasolacrimal duct dilatation, and obstruction. Laboratory examination of the cyst confirmed the diagnosis of dacryops, a cyst of lacrimal gland origin. The cyst was treated successfully with surgical drainage and curettage.

Retrograde air escape via the nasolacrimal system: a previously unrecognized complication of continuous positive airway pressure in the management of obstructive sleep apnea.

PubMed

Singh, Narinder Pal; Walker, Robbie James Eades; Cowan, Fiona; Davidson, Arthur Craig; Roberts, David Newton

2014-05-01

Continuous positive airway pressure (CPAP) is the gold standard treatment for moderate to severe obstructive sleep apnoea (OSA). Eye-related side effects of CPAP are commonly attributed to a poorly sealed mask, allowing leaked air to blow over the eye. We present 3 cases where attended polysomnography (A-PSG) demonstrated CPAP-associated retrograde air escape via the nasolacrimal system (CRANS) in the absence of any mask leaks. Symptoms included dry eye, epiphora, air escape from the medial canthus, and eyelid flutter. Symptoms were controlled with a variety of surgical and nonsurgical techniques. CRANS represents a previously undescribed clinical entity. CRANS may be responsible for some CPAP-related eye side effects and possibly for rarer secondary eye complications, including conjunctivitis and corneal ulceration. CRANS should be suspected in any patient on CPAP complaining of eye symptoms. CRANS may be diagnosed through careful observation during A-PSG and confirmed by performing a "saline bubble test." Management options include nonsurgical (mask alternatives, humidification, nasopharyngeal airway) and surgical techniques (nasal airway surgery, inferior turbinate out-fracture and adhesion, injection of bulking agent around Hasner's valve).

Management of functional epiphora in patients with an anatomically patent dacryocystorhinostomy.

PubMed

Shams, Pari N; Chen, Philip G; Wormald, Peter J; Sloan, Brian; Wilcsek, Geoff; McNab, Alan; Selva, Dinesh

2014-09-01

Approximately 5% to 10% of patients continue to experience persistent epiphora following an anatomically successful dacryocystorhinostomy (DCR) for nasolacrimal duct obstruction or stenosis. To investigate the management and success rate of so-called "functional failure" of DCR for nasolacrimal duct obstruction by experienced lacrimal surgeons. Multicenter retrospective case series including 5 Australian and New Zealand centers. Participants included 61 patients (71% women [n = 46]; mean age, 66 years) with functional epiphora after 65 DCRs (69% transnasal) who were recruited over a mean of 7.6 years. Inclusion criteria included confirmed preoperative diagnosis of nasolacrimal duct obstruction or stenosis, age greater than 18 years, recurrent or persistent epiphora after DCR, an anatomically successful DCR, and follow-up longer than 6 months. Exclusion criteria included evidence of lacrimal hypersecretion, eyelid malposition, and punctal or canalicular abnormalities. The number, type, timing, and success of all clinical interventions performed for the management of functional epiphora after DCR. Epiphora recurred a mean of 8.9 months after primary DCR; 89% of the cases (n = 58) had evidence of a patent ostium and 100% were patent on lacrimal irrigation. Intubation with a lacrimal stent was performed in 82% of the cases at the time of surgery, and all stents were removed a mean of 8 weeks postoperatively. Epiphora was reported immediately following DCR in 32% (n = 21) of the cases and within 6 weeks after removal of the stent in 31% (n = 20); late recurrence (>12 months after DCR) developed in 37% (n = 24) of the cases. In a total of 15% of the cases, participants declined any treatment following DCR. The remainder underwent a mean of 1.3 interventions (range, 1-3) during a mean of 23 to 41 months after primary DCR, following which 72% (n = 47) of the cases had a successful outcome; 12% (n = 8) failed to achieve improvement, and the patients declined further

Utility of Diffusion-Weighted MRI to Detect Changes in Liver Diffusion in Benign and Malignant Distal Bile Duct Obstruction: The Influence of Choice of b-Values.

PubMed

Karan, Belgin; Erbay, Gurcan; Koc, Zafer; Pourbagher, Aysin; Yildirim, Sedat; Agildere, Ahmet Muhtesem

2016-11-01

The study sought to evaluate the potential of diffusion-weighted magnetic resonance imaging to detect changes in liver diffusion in benign and malignant distal bile duct obstruction and to investigate the effect of the choice of b-values on apparent diffusion coefficient (ADC). Diffusion-weighted imaging was acquired with b-values of 200, 600, 800, and 1000 s/mm 2 . ADC values were obtained in 4 segments of the liver. The mean ADC values of 16 patients with malignant distal bile duct obstruction, 14 patients with benign distal bile duct obstruction, and a control group of 16 healthy patients were compared. Mean ADC values for 4 liver segments were lower in the malignant obstruction group than in the benign obstruction and control groups using b = 200 s/mm 2 (P < .05). Mean ADC values of the left lobe medial and lateral segments were lower in the malignant obstruction group than in the benign obstructive and control groups using b = 600 s/mm 2 (P < .05). Mean ADC values of the right lobe posterior segment were lower in the malignant and benign obstruction groups than in the control group using b = 1000 s/mm 2 (P < .05). Using b = 800 s/mm 2 , ADC values of all 4 liver segments in each group were not significantly different (P > .05). There were no correlations between the ADC values of liver segments and liver function tests. Measurement of ADC shows good potential for detecting changes in liver diffusion in patients with distal bile duct obstruction. Calculated ADC values were affected by the choice of b-values. Copyright © 2016 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

Halofuginone can worsen liver fibrosis in bile duct obstructed rats.

PubMed

Van de Casteele, Marc; Roskams, Tania; Van der Elst, Ingrid; van Pelt, Jos F; Fevery, Johan; Nevens, Frederik

2004-10-01

Halofuginone (HF) is an antifibrotic agent in rat models of liver fibrosis caused by repetitive intoxications. A beneficial effect of HF on a biliary type of liver fibrosis has not been proven yet. Bile duct-obstructed rats were given HF from the moment of obstruction onwards and compared with no treatment. After 3 weeks, respectively, 6 weeks, aminopyrine breath test (ABT) and haemodynamic measurements including of portal pressure were carried out. Liver pieces were taken for Sirius red quantitative scoring, as well as for semiquantitative determinations of collagen type I and III RNA levels. ABT was significantly worse in HF-treated rats as compared with no treatment (P=0.02). Haemodynamic data and collagen type I and III determinations were not significantly different between groups. Biliary fibrosis scores were significantly higher in HF-treated rats as compared with no treatment (P=0.03). More Sirius red staining was associated with more proliferation of bile ductules. HF may worsen biliary fibrosis. This contrasts sharply with antifibrotic effects in other models of liver fibrosis. Distinctive cellular mechanisms in biliary fibrosis may explain this discrepancy. One should be cautious for chronic application of HF in man with cholestasis.

Laparoscopic Longitudinal Pancreaticojejunostomy Using Barbed Sutures: an Efficient and Secure Solution for Pancreatic Duct Obstructions in Patients with Chronic Pancreatitis.

PubMed

Kim, Eun Young; Hong, Tae Ho

2016-04-01

We describe our laparoscopic longitudinal pancreaticojejunostomy (LPJ) technique using barbed sutures to manage a pancreatic duct obstruction. We performed laparoscopic longitudinal anterior pancreaticojejunostomy using barbed sutures (3-0 absorbable wound closure device, V-Loc, Covidien, Minneapolis, MN, USA) in 11 patients who presented with signs of a pancreas ductal obstruction and chronic pancreatitis. The surgical outcomes and follow-up records at the outpatient department were reviewed, and the effectiveness and feasibility of this method were analyzed. Mean patient age was 54.4 ± 9.5 years, and pancreatic duct stones were removed from all patients without conversion to laparotomy. Overall operative time was 200.7 ± 56.4 min, and estimated blood loss was 42.2 ± 11.2 ml. No pancreatic anastomosis leakage or postoperative bleeding was detected. Mean length of hospital stay was 6.5 ± 0.8 days, and mean time to start a soft diet was 4.8 ± 0.7 days. No patient complained of postoperative abdominal pain, and all patients recovered without significant complications or relapse of pancreatitis. The follow-up period was 4-21 months. Our new laparoscopic longitudinal anterior pancreaticojejunostomy technique (Puestow procedure) using barbed sutures is a potentially efficient and minimally invasive procedure for patients who suffer from pancreatic duct obstruction and chronic pancreatitis.

Development of the nasolacrimal apparatus in the Mongolian gerbil (Meriones unguiculatus), with notes on network topology and function.

PubMed

Rehorek, Susan J; Cunningham, Jayna; Bruening, Amanda E; Johnson, Jessica L; Bhatnagar, Kunwar P; Smith, Timothy D; Hillenius, Willem J

2015-09-01

The nasolacrimal apparatus (NLA) is a multicomponent functional system comprised of multiple orbital glands (up to four larger multicellular exocrine structures), a nasal chemosensory structure (vomeronasal organ: VNO), and a connecting duct (nasolacrimal duct: NLD). Although this system has been described in all tetrapod vertebrate lineages, albeit not always with all three main components present, considerably less is known about its ontogeny. The Mongolian gerbil (Meriones unguiculatus) is a common lab rodent in which the individual components of the adult NLA have been well studied, but as yet nothing is known about the ontogeny of the NLA. In this study, serial sections of 15 fetal and three adult Mongolian gerbil heads show that the development of the NLA falls into three fetal stages: inception (origin of all features), elongation (lengthening of all features), and expansion (widening of all features). No postnatal or juvenile specimens were observed in this study, but considerable growth evidently occurs before the final adult condition is reached. The development of the orbital glands and the VNO in the Mongolian gerbil is largely consistent with those in other mammals, despite a slight nomenclatural conundrum for the anterior orbital glands. However, the Mongolian gerbil NLD follows a more circuitous route than in other tetrapods, due mainly to the convoluted arrangement of the narial cartilages, the development of a pair of enlarged incisors as well as an enlarged infraorbital foramen. The impact of these associated features on the ontogeny and phylogeny of the NLA could be examined through the approach of network science. This approach allows for the incorporation of adaptations to specific lifestyles as potential explanations for the variation observed in the NLA across different tetrapod clades. © 2015 Wiley Periodicals, Inc.

Biliary Stenosis and Gastric Outlet Obstruction: Late Complications After Acute Pancreatitis With Pancreatic Duct Disruption.

PubMed

Sugimoto, Motokazu; Sonntag, David P; Flint, Greggory S; Boyce, Cody J; Kirkham, John C; Harris, Tyler J; Carr, Sean M; Nelson, Brent D; Bell, Don A; Barton, Joshua G; Traverso, L William

2018-07-01

Pancreatic duct disruption (PDD) after acute pancreatitis can cause pancreatic collections in the early phase and biliary stenosis (BS) or gastric outlet obstruction (GOO) in the late phase. We aimed to document those late complications after moderate or severe acute pancreatitis. Between September 2010 and August 2014, 141 patients showed pancreatic collections on computed tomography. Percutaneous drainage was primarily performed for patients with signs or symptoms of uncontrolled pancreatic juice leakage. Pancreatic duct disruption was defined as persistent amylase-rich drain fluid or a pancreatic duct cut-off on imaging. Clinical course of the patients who developed BS or GOO was investigated. Among the 141 patients with collections, 33 patients showed PDD in the pancreatic head/neck area. Among them, 9 patients (27%) developed BS 65 days after onset and required stenting for 150 days, and 5 patients (15%) developed GOO 92 days after onset and required gastric decompression and jejunal tube feeding for 147 days (days shown in median). All 33 patients recovered successfully without requiring surgical intervention. Anatomic proximity of the bile duct or duodenum to the site of PDD and severe inflammation seemed to contribute to the late onset of BS or GOO. Conservative management successfully reversed these complications.

Lesions of the segmental and lobar hepatic ducts.

PubMed Central

Longmire, W P; Tompkins, R K

1975-01-01

Despite reports to the contrary, unobstructed drainage of 50% of an otherwise normal liver through either the right or left uninfected hepatic duct is adequate to restore normal liver function, even if the obstructed lobe remains in place. An undrained liver lobe, if present, may require no further treatment. As long as it is completely obstructed and uninfected, it will undergo a progressive asymptomatic atrophy. Cholangitis invariably develops behind a partial lobar ductal obstruction, producing jaundice, pruritis, and fever. Unless unobstructed, uninfected biliary flow can be achieved through a segmental or lobar duct, it is better that the duct be completely obstructed and the affected liver parenchyma allowed to atrophy, provided there is normal biliary flow from the residual 50% of liver. This concept is important in the management of injured anomalous segmental or lobar hepatic duct and in the palliative treatment of bile duct carcinoma. Localized intrahepatic infections communicating with abnormal biliary ducts will require hepatic resection of the infected parenchyma and ducts for cure. The abnormality may be saccular dilatation of the intrahepatic ductal system with abscess formation or intrahepatic abscess associated with stenosis of the ductal system from trauma to the duct, to the duct and liver, or to retained intrahepatic stones. Diffusely situated intrahepatic abscesses secondary to ductal abnormalities can be treated with systemic antibiotics, local drainage of a dmoninant abscess, and efforts to improve biliary drainage. Images Fig. 4. Fig. 5. Fig. 6. Fig. 8. Fig. 9. Fig. 10. Figs. 11A and B Figs. 12A and B. Fig. 13. Fig. 14. Fig. 15. Fig. 16. Fig. 17. PMID:1180585

Hepatectomy for Hepatocellular Carcinoma with Bile Duct Tumor Thrombus, Including Cases with Obstructive Jaundice.

PubMed

Orimo, Tatsuya; Kamiyama, Toshiya; Yokoo, Hideki; Wakayama, Kenji; Shimada, Shingo; Tsuruga, Yosuke; Kamachi, Hirofumi; Taketomi, Akinobu

2016-08-01

This study aimed to evaluate the short- and long-term outcomes of hepatectomy for hepatocellular carcinoma (HCC) with bile duct tumor thrombus (BDTT), including cases with obstructive jaundice. The study reviewed 42 HCC patients with BDTT, including six patients who needed preoperative biliary drainage due to obstructive jaundice, and 732 HCC patients without BDTT. The authors analyzed the impact of BDTT on the surgical outcomes and assessed the outcomes of hepatectomy for patients presenting with obstructive jaundice. The HCC patients with BDTT, almost all with stage 3 or 4 disease, had increased alpha-fetoprotein expression, larger tumors, and more portal vein invasion status. The survival of the HCC patients with BDTT was significantly inferior to that of the patients without BDTT (p = 0.0003). Survival did not differ significantly between the HCC patients with BDTT and those without BDTT when the two groups were matched by stage (p = 0.3366). The HCC patients with BDTT who presented with obstructive jaundice demonstrated outcomes similar to those for the HCC patients with BDTT who did not present with obstructive jaundice in terms of the overall survival rate (p = 0.5469). The perioperative outcomes for the HCC patients with BDTT did not depend on the presence or absence of preoperative jaundice. No patients in either BDTT group demonstrated 90-day mortality in this study. Hepatectomy should be considered for HCC patients with BDTT, even for patients with obstructive jaundice, because the surgical outcomes equivalent to those for HCC without BDTT can be achieved.

Carcinoids of the common bile duct: a case report and literature review

PubMed Central

Ross, Alison C.; Hurley, James B.; Hay, W. Bruce; Rusnak, Conrad H.; Petrunia, Denis M.

1999-01-01

Carcinoids of the extrahepatic bile ducts and particularly the common bile duct are extremely rare. A 65-year-old woman presented with obstructive jaundice. Laboratory and imaging studies gave results that were consistent with an obstructing lesion in the common bile duct. In this case, a stent was inserted initially to decompress the bile ducts. Subsequently a laparotomy and pancreaticoduodenectomy were performed and a tissue diagnosis of carcinoid of the common bile duct was made. The patient was well with no evidence of recurrence 17 months postoperatively. The authors believe this is the 19th reported case of an extrahepatic bile duct carcinoid. PMID:10071590

Biofilm Quantification on Nasolacrimal Silastic Stents After Dacryocystorhinostomy.

PubMed

Murphy, Jae; Ali, Mohammed Javed; Psaltis, Alkis James

2015-01-01

Biofilms are now recognized as potential factors in the pathogenesis of chronic inflammatory and infective diseases. The aim of this study was to examine the presence of biofilms and quantify their biomass on silastic nasolacrimal duct stents inserted after dacryocystorhinostomy (DCR). A prospective study was performed on a series of patients undergoing DCR with O'Donoghue stent insertion. After removal, the stents were subjected to biofilm analysis using standard protocols of confocal laser scanning microscopy (CLSM) and scanning electron microscopy. These stents were compared against negative controls and positive in vitro ones established using Staphylococcus aureus strain ATCC 25923. Biofilm quantification was performed using the COMSTAT2 software and the total biofilm biomass was calculated. A total of nine consecutive patient samples were included in this prospective study. None of the patients had any evidence of postoperative infection. All the stents demonstrated evidence of biofilm formation using both imaging modalities. The presence of various different sized organisms within a common exopolysaccharide matrix on CLSM suggested the existence of polymicrobial communities. The mean biomass of patient samples was 0.9385 μm³/μm² (range: 0.3901-1.9511 μm³/μm²). This is the first study to report the quantification of biomass on lacrimal stents. The presence of biofilms on lacrimal stents after DCR is a common finding but this need not necessarily translate to postoperative clinical infection.

[Persistence [corrected] of onphalomesenteric duct as intestinal obstruction cause in a adult. Report of a case in the Hipolito Unanue Nacional Hospital].

PubMed

Gutiérrez Ccencho, C; Luna Cydejko, Jc; Gutierrez De Aranguren, Cf; Revoredo, Fernando; Soto Tarazona, A; Olazábal Ramírez, V

2008-01-01

The persistence of the onphalomesenteric duct has been reported in several pediatric publications either through the appearance of Meckel diverticulum that are commonest, or by the appearance of segments with partial or total permeability of itself. Sporadic cases have appeared where this anomaly has originated episodes of intestinal obstruction in infants and children specially under the form of a fibrous band. However, adult presentations extremely infrequent. The case presented in this report shows compatible findings with a onphalomesenteric conduit with partial permeability, that I originate an intestinal picture of obstruction in a young adult.

Common bile duct stricture as a late complication of upper abdominal radiotherapy.

PubMed

Cherqui, D; Palazzo, L; Piedbois, P; Charlotte, F; Duvoux, C; Duron, J J; Fagniez, P L; Valla, D

1994-06-01

We report the cases of two patients who developed symptomatic common bile duct stricture 10 years after upper abdominal radiotherapy for malignant lymphoma. Both patients were in complete remission and presented with marked obstructive jaundice. Endosonography was useful in both cases and showed segmental thickening of the bile duct wall narrowing in the lumen. Both patients underwent surgical exploration, confirming biliary obstruction due to intrinsic wall thickening, and had successful biliary drainage by Roux-en-Y hepatico-jejunostomy. Histological examination of the resected bile duct, in one case, and of a bile duct biopsy, in the other, was consistent with late irradiation injury. We conclude that stricture may be a delayed consequence of radiotherapy applied to normal bile ducts.

Bare-metal stents across the Vater's ampulla is a safe method for patients with lower bile duct obstruction

PubMed Central

Mao, Xiao-Nan; Lu, Zai-Ming; Wen, Feng; Liang, Hong-Yuan; Guo, Qi-Yong

2017-01-01

Abstract This study explored the effect of the implant position of stents across the Vater's ampulla on treatment outcomes in patients with lower bile duct obstruction. In the retrospective study, 41 patients with malignant obstruction of the lower bile duct and obstructive jaundice received percutaneous transhepatic biliary placement of bare-metal stents. Basic demographic data on patients, such as sex, age, and primary diseases, and follow-up data, including postoperative complications and jaundice-free survival, were recorded. The follow-up data on patients with an involved ampulla, patients with an uninvolved ampulla, patients with a stent across the ampulla, and patients with a stent at a site other than the ampulla were compared. Furthermore, prognostic factors for jaundice- free survival were investigated using Cox proportional hazards regression analysis. Among the 41 patients, 38 patients experienced subsiding of jaundice, whereas 3 cases had unsuccessful stent patency. Whether or not the ampulla was involved did not influence the incidence rates of postoperative complications and the jaundice-free survival time. Notably, when stents were placed across the ampulla, the jaundice-free survival time was significantly longer than when stents were placed at sites other than across the ampulla (P < .05). Furthermore, placement of the stent across the ampulla or at other sites was an independent prognostic factor (hazard ratio = 0.154, 95% confidence interval 0.042–0.560, P = .005) for jaundice-free survival of patients. The current study revealed that the implant position of a stent across the ampulla resulted in maintenance of stent patency and prolongation of the jaundice-free survival time. PMID:29137005

Palliation double stenting for malignant biliary and duodenal obstruction

PubMed Central

ZHAO, LIANG; XU, HAITAO; ZHANG, YUBAO

2016-01-01

The surgical management of patients with malignant biliary and duodenal obstruction is complex. Tumor excision is no longer possible in the majority of patients with malignant obstructive jaundice and duodenal obstruction. The aim of the present study was to evaluate the effectiveness of intraluminal dual stent placement in malignant biliary and duodenal obstruction. In total, 20 patients with malignant obstructive jaundice and duodenal obstruction, including 6 with pancreatic carcinoma, 11 with cholangiocarcinoma, 1 with duodenal carcinoma and 2 with abdominal lymph node metastasis, were treated with intraluminal stent placement. Bile duct obstruction with late occurrence of duodenal obstruction was observed in 16 cases, and duodenal obstruction followed by a late occurrence of bile duct obstruction was observed in 3 cases, while, in 1 case, bile duct obstruction and duodenal obstruction occurred simultaneously. After X-ray fluoroscopy revealed obstruction in the bile duct and duodenum, stents were placed into the respective lumens. Percutaneous transhepatic placement was employed for the biliary stent, while the duodenal stent was placed perioraly. The clinical outcomes, including complications associated with the procedures and patency of the stents, were evaluated. The biliary and duodenal stents were successfully implanted in 18 patients and the technical success rate was 90% (18/20). A total of 39 stents were implanted in 20 patients. In 2 cases, duodenal stent placement failed following biliary stent placement. Duodenal obstruction remitted in 15 patients, and 1 patient succumbed to aspiration pneumonia 5 days after the procedure. No severe complications were observed in any other patient. The survival time of the 18 patients was 5–21 months (median, 9.6 months), and 6 of those patients survived for >12 months. The present study suggests that X-ray fluoroscopy-guided intraluminal stent implantation is an effective procedure for the treatment of malignant

Conservation of pancreatic tissue by combined gastric, biliary, and pancreatic duct drainage for pain from chronic pancreatitis.

PubMed

Warshaw, A L

1985-04-01

In patients with chronic pancreatitis, the sclerosing process of the pancreas may constrict not only the pancreatic duct for also the bile duct and duodenum. This study analyzes the prevalence of these obstructive lesions in 58 consecutive patients with chronic pancreatitis requiring surgery for either pain (57 patients) or for painless jaundice (1 patient). There was significant biliary obstruction in 21, 4 of whom also had symptomatic duodenal obstruction. All 21 patients with biliary and duodenal obstruction were among the 38 with a dilated pancreatic duct suitable for pancreaticojejunostomy (modified Puestow procedure). None of the 20 patients with small duct pancreatitis had biliary or duodenal obstruction. Pseudocysts were distributed evenly between the two groups (9 of 38 patients with a dilated duct versus 4 of 20 patients with small duct pancreatitis). Pancreaticojejunostomy combined with choledochoenterostomy and gastrojejunostomy in appropriately selected patients provided good to excellent long-term (mean 3.6 years) relief of pain in 30 of 36 patients (83 percent). There was no correlation between successful relief of pain and development of pancreatic exocrine or endocrine insufficiency or calcification. Stenosis of the bile duct developed some years subsequent to pancreaticojejunostomy in four patients and required a second operation for choledochoenterostomy in three. Three other patients required secondary pancreatic resections due to failure of the pancreaticojejunostomy to relieve pain. It is often possible to effect excellent relief of symptoms with maximal conservation of remaining pancreatic functions despite sclerotic obstruction of multiple organ systems.

Inaccuracy of diagnosis in a cohort of patients on the waiting list for dacryocystorhinostomy when the diagnosis was made by only syringing the lacrimal system.

PubMed

Beigi, B; Uddin, J M; McMullan, T F W; Linardos, E

2007-01-01

Accurate identification of the factors contributing to epiphora is essential in directing appropriate management and treatment strategies. The authors applied a methodical strategy of assessment for epiphora to patients who were already on the waiting list for dacryocystorhinostomy (DCR). The findings were compared to the original findings. Forty-four eyes of 35 patients listed for DCR were re-examined. All canaliculi were examined using four tests: dye disappearance, Jones 1 (dye retrieval), probing using Bowman probes, and syringing of the nasolacrimal duct (NLD) under local anesthesia. Some patients were examined using an endocanalicular mini-endoscope. Patients with NLD obstruction underwent DCR and those with canalicular and NLD stenosis underwent intubation of the lacrimal system-canaliculus, lacrimal sac, and nasolacrimal duct-using silicone stents. The authors refer to this as canaliculodacryocystoplasty (CDCP). The patients were assessed for symptoms of epiphora at 12 months. Forty-four eyes had been listed for DCR. They had been originally diagnosed, by means of lacrimal syringing, as NLD obstruction (24 eyes) or stenosis (12 eyes), and functional blocks (8 eyes). Four out of the original 44 planned DCR surgeries were performed after re-evaluation. After re-examination, 28 lacrimal systems were found to have canalicular stenosis, 4 NLD stenosis, 4 NLD obstruction, 4 punctal phimosis, 3 ocular surface disease, and 1 patient was asymptomatic. Twenty-eight lacrimal systems underwent CDCP, 4 underwent DCR, 4 had punctoplasty, and 4 had probing alone. Three had treatment for ocular surface disease and one patient required no treatment. After a follow-up of 12 months, 41 (93%) systems had improvement or were free of their Syringing of the lacrimal apparatus may result in a high false positive diagnosis of NLD obstruction. Canalicular pathology is not uncommon in this cohort of patients and may be underdiagnosed.

Case-controlled clinical and histopathological study of conjunctivochalasis.

PubMed

Francis, I C; Chan, D G; Kim, P; Wilcsek, G; Filipic, M; Yong, J; Coroneo, M T

2005-03-01

Conjunctivochalasis, a secondary cause of the watery eye, is frequently seen in the older age group as an elevation of the bulbar conjunctiva lying along the lateral or central lower lid margin. A prospective, interventional, case-controlled clinical and histopathological study was conducted. The relevant features of 18 patients (29 eyes) who had their conjunctivochalasis resected as part of the surgical management of their watery eye syndrome were examined. In the control group, tissue was obtained from an age matched series of 24 normal subjects undergoing routine cataract surgery. 24 controls (24 specimens) and 18 patients (29 specimens) had conjunctival strip biopsies, taken from the usual lid margin level bulbar conjunctiva in line with the inferior limbus (controls), and the clinically apparent conjunctivochalasis (patients). These were submitted for histological study. 23 of 24 control sections demonstrated normal conjunctival variation. Four of 29 patient specimens demonstrated a chronic non-granulomatous conjunctivitis, while three eyes of the patient group (two patients) demonstrated features of elastosis. Of the four patients who had the inflammatory infiltrates, three had functional nasolacrimal duct obstructions (FNLDOs) and one had a primary acquired nasolacrimal duct obstruction (PANDO). Of the two patients who had elastosis, one had an FNLDO and the other had normal lacrimal drainage and was Jones 1 positive. Six of 18 patients--that is, seven of 29 specimens of conjunctivochalasis demonstrated signs of elastosis or of chronic non-granulomatous inflammation. Clinically, patients had a spectrum of aetiologies of their watery eye syndrome.

The punctal apposition syndrome: a new surgical approach.

PubMed

Francis, I C; Wan, M K

2002-11-01

To assess the punctal apposition syndrome (PAS) and its response to lateral canthal tendon (LCT) repair. In this retrospective, interventional case series, five patients (seven symptomatic eyes) with PAS were managed. Lateral canthal tendon repair was performed in all seven eyes. The main outcome measure was correction of watery eye symptomatology. All five patients achieved symptomatic resolution. Conjunctivochalasis and functional nasolacrimal duct obstruction were associated with the PAS. This new surgical approach to the PAS, using a LCT repair, was successful in all patients. Two patients (three eyes) required conjunctivochalasis excision.

Generalized osteosclerosis in a cat.

PubMed

Hanel, Rita M; Graham, John P; Levy, Julie K; Buergelt, Claus D; Creamer, Jeff

2004-01-01

A 12-year-old, neutered male, domestic long-hair cat was evaluated for a 6-month history of inspiratory stertor and epiphora. In computed tomography of the skull and pelvis, and radiographs of the thorax, right femur and stifle there was generalized osteosclerosis, with obliteration of the nasal turbinates and nasolacrimal duct obstruction. The cat also had a large fibrosarcoma involving the right pelvic limb. Osteosclerosis is a rare disorder that is poorly understood but has been described in several species. Various manifestations, potential causes, and radiologic findings of osteosclerosis are discussed.

Vitellointestinal Duct Anomalies in Infancy.

PubMed

Kadian, Yogender Singh; Verma, Anjali; Rattan, Kamal Nain; Kajal, Pardeep

2016-01-01

Vitellointestinal duct (VID) or omphalomesenteric duct anomalies are secondary to the persistence of the embryonic vitelline duct, which normally obliterates by weeks 5-9 of intrauterine life. This is a retrospective analysis of a total of 16 patients of symptomatic remnants of vitellointestinal duct from period of Jan 2009 to May 2013. Male to female ratio (M:F) was 4.3:1 and mean age of presentation was 2 months and their mode of presentation was: patent VID in 9 (56.25%) patients, umbilical cyst in 2(12.25%), umbilical granuloma in 2 (12.25%), and Meckel diverticulum as content of hernia sac in obstructed umbilical hernia in 1 (6.25%) patient. Two patients with umbilical fistula had severe electrolyte disturbance and died without surgical intervention. Persistent VID may have varied presentations in infancy. High output umbilical fistula and excessive bowel prolapse demand urgent surgical intervention to avoid morbidity and mortality.

Choleperitoneum due to intrahepatic bile duct rupture - case report.

PubMed

Simion, L; Straja, Dn; Prunoiu, Vm; Alecu, M; Brătucu, E

2014-01-01

Non-traumatic perforations of the bile ducts are unfrequently encountered entities, all the more when they affect the intrahepatic bile ducts, exteriorizing their biliary content in the great peritoneal cavity. Reporting such a case has determined the authors to perform a careful overview of the cases present in the literature. An observation that can be made based on these is that the obstruction of the main bile duct due to lithiasis determines, by pressure increase, the dilation of the bile system branches, all on the background of an unknown malformation of the intrahepatic bile ducts. Celsius.

Long-term follow-up of external dacryocystorhinostomy and the factors affecting its success.

PubMed

Erdöl, Hidayet; Akyol, Nurettin; Imamoglu, Halil Ibrahim; Sözen, Engin

2005-06-01

To evaluate the long-term follow-up results of external dacryocystorhinostomy (Ex-DCR) and to assess the role of some factors in its success. Between January 1990 and November 2002, 437 nasolacrimal systems of 387 patients were operated on and included in the study. The success rates were determined on the basis of the last examinations of the patients, and the correlations between success rates and factors such as age, gender, the duration of obstruction, history of acute dacryocystitis, the side of obstruction, and the postoperative follow-up period were calculated. The mean follow-up period was 5.9 +/- 2.5 years. Fifty cases (12.9%) were operated bilaterally. The initial success rate was 91.5% and the last success rate was 98.4% after reoperations. We found meaningful correlations between success and duration of obstruction, age of the patient, and the duration of postoperative follow-up (r = 0.18, 0.17 and -0.14, p = 0.036, 0.001 and 0.002, respectively). In comparison to newly developed surgical techniques for the treatment of nasolacrimal duct obstruction, Ex-DCR still appears to offer higher success rates, even after long-term follow-up. In addition to being a cost-effective procedure, it requires no sophisticated instruments. In our opinion, the high success rates may be explained by the nature of the operation, which creates a fistula between the sac and the nasal mucosa.

Vitellointestinal Duct Anomalies in Infancy

PubMed Central

Kadian, Yogender Singh; Verma, Anjali; Rattan, Kamal Nain; Kajal, Pardeep

2016-01-01

Background: Vitellointestinal duct (VID) or omphalomesenteric duct anomalies are secondary to the persistence of the embryonic vitelline duct, which normally obliterates by weeks 5–9 of intrauterine life. Methods: This is a retrospective analysis of a total of 16 patients of symptomatic remnants of vitellointestinal duct from period of Jan 2009 to May 2013. Results: Male to female ratio (M:F) was 4.3:1 and mean age of presentation was 2 months and their mode of presentation was: patent VID in 9 (56.25%) patients, umbilical cyst in 2(12.25%), umbilical granuloma in 2 (12.25%), and Meckel diverticulum as content of hernia sac in obstructed umbilical hernia in 1 (6.25%) patient. Two patients with umbilical fistula had severe electrolyte disturbance and died without surgical intervention. Conclusion: Persistent VID may have varied presentations in infancy. High output umbilical fistula and excessive bowel prolapse demand urgent surgical intervention to avoid morbidity and mortality. PMID:27433448

Toll-Like Receptors in Secondary Obstructive Cholangiopathy

PubMed Central

Miranda-Díaz, A. G.; Alonso-Martínez, H.; Hernández-Ojeda, J.; Arias-Carvajal, O.; Rodríguez-Carrizalez, A. D.; Román-Pintos, L. M.

2011-01-01

Secondary obstructive cholangiopathy is characterized by intra- or extrahepatic bile tract obstruction. Liver inflammation and structural alterations develop due to progressive bile stagnation. Most frequent etiologies are biliary atresia in children, and hepatolithiasis, postcholecystectomy bile duct injury, and biliary primary cirrhosis in adults, which causes chronic biliary cholangitis. Bile ectasia predisposes to multiple pathogens: viral infections in biliary atresia; Gram-positive and/or Gram-negative bacteria cholangitis found in hepatolithiasis and postcholecystectomy bile duct injury. Transmembrane toll-like receptors (TLRs) are activated by virus, bacteria, fungi, and parasite stimuli. Even though TLR-2 and TLR-4 are the most studied receptors related to liver infectious diseases, other TLRs play an important role in response to microorganism damage. Acquired immune response is not vertically transmitted and reflects the infectious diseases history of individuals; in contrast, innate immunity is based on antigen recognition by specific receptors designated as pattern recognition receptors and is transmitted vertically through the germ cells. Understanding the mechanisms for bile duct inflammation is essential for the future development of therapeutic alternatives in order to avoid immune-mediated destruction on secondary obstructive cholangiopathy. The role of TLRs in biliary atresia, hepatolithiasis, bile duct injury, and primary biliary cirrhosis is described in this paper. PMID:22114589

[Antegrade visualization of the billiary duct system by percutaneous transjugular cholangiography (author's transl)].

PubMed

Huchzermeyer, H; Luska, G; Freuschmidt, J

1976-01-01

Percutaneous transjugular cholangiography (PTJC) is a new technique for visualization of the biliary duct system and for diagnosis of obstructive jaundice. First experiences of the authors in 22 patients are described. The advantages and disadvantages of this procedure, which at the present time is used rather rarely, are discussed and compared to various other cholangiographic methods. The endoscopic retrograde cholangiography (ERC) was used for patients with obstructive jaundice of unknown origine in the first place. If the biliary duct system could not be visualized by ERC (failure of complete obstruction of the common bile duct), the antegrade technique (PTJC) was performed. The peritoneoscopic and the transjugular cholangiography yield about the same percentage of positive results (90%), as far as visualization of the biliary tree is concerned. However in contrast to the peritoneoscopic methods PTJC seems to bear a smaller risk of complications. Some further diagnostic and therapeutical advantages, which might result from the use of PTJC are pointed out.

Surgical treatment of dacryocystitis caused by cystic dilatation of the nasolacrimal system in three dogs.

PubMed

van der Woerdt, A; Wilkie, D A; Gilger, B C; Smeak, D D; Kerpsack, S J

1997-08-15

A 4-year-old castrated male Golden Retriever was referred for evaluation of intermittent purulent discharge from the right eye of 4-months' duration. A radiolucent area in the maxillary bone was detected on examination of skull radiographs. Dacryocystorhinography revealed pooling of contrast material in the radiolucent area. A rhinotomy was performed, and a large opening between the cystic structure of the nasolacrimal system and the nasal cavity was created. Epiphora resolved after surgery and had not recurred by 9 months after surgery. Two other dogs had cystic structures of the nasolacrimal system and were treated surgically to allow drainage into the nasal cavity.

Pipe crawler development for duct elbow removal

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

Zollinger, W.T.; Treanor, R.C.

1992-01-01

This paper describes the development of equipment for removing an elbow in a 36 inch diameter ventilation line by cutting from the inside. Radiation levels, high air flow and physical constraints preclude any manual rework of the ventilation system. A remotely operated pipe crawler was developed. Testing has been performed in a full-scale mockup which models the ventilation duct configuration with the exception of radiation levels. The results gathered from the testing are discussed, and illustrate the strengths and weaknesses of the crawler and plasma arc torch system. To date, the equipment has successfully completed the tasks of maneuvering throughmore » the duct geometry, performing the two required cuts, and backing out of the duct mockup. The elbow successfully fell away from the main duct, showing that the line would be clear of obstructions.« less

Pipe crawler development for duct elbow removal

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

Zollinger, W.T.; Treanor, R.C.

1992-11-01

This paper describes the development of equipment for removing an elbow in a 36 inch diameter ventilation line by cutting from the inside. Radiation levels, high air flow and physical constraints preclude any manual rework of the ventilation system. A remotely operated pipe crawler was developed. Testing has been performed in a full-scale mockup which models the ventilation duct configuration with the exception of radiation levels. The results gathered from the testing are discussed, and illustrate the strengths and weaknesses of the crawler and plasma arc torch system. To date, the equipment has successfully completed the tasks of maneuvering throughmore » the duct geometry, performing the two required cuts, and backing out of the duct mockup. The elbow successfully fell away from the main duct, showing that the line would be clear of obstructions.« less

Murine model of long term obstructive jaundice

PubMed Central

Aoki, Hiroaki; Aoki, Masayo; Yang, Jing; Katsuta, Eriko; Mukhopadhyay, Partha; Ramanathan, Rajesh; Woelfel, Ingrid A.; Wang, Xuan; Spiegel, Sarah; Zhou, Huiping; Takabe, Kazuaki

2016-01-01

Background With the recent emergence of conjugated bile acids as signaling molecules in cancer, a murine model of obstructive jaundice by cholestasis with long-term survival is in need. Here, we investigated the characteristics of 3 murine models of obstructive jaundice. Methods C57BL/6J mice were used for total ligation of the common bile duct (tCL), partial common bile duct ligation (pCL), and ligation of left and median hepatic bile duct with gallbladder removal (LMHL) models. Survival was assessed by Kaplan-Meier method. Fibrotic change was determined by Masson-Trichrome staining and Collagen expression. Results 70% (7/10) of tCL mice died by Day 7, whereas majority 67% (10/15) of pCL mice survived with loss of jaundice. 19% (3/16) of LMHL mice died; however, jaundice continued beyond Day 14, with survival of more than a month. Compensatory enlargement of the right lobe was observed in both pCL and LMHL models. The pCL model demonstrated acute inflammation due to obstructive jaundice 3 days after ligation but jaundice rapidly decreased by Day 7. The LHML group developed portal hypertension as well as severe fibrosis by Day 14 in addition to prolonged jaundice. Conclusion The standard tCL model is too unstable with high mortality for long-term studies. pCL may be an appropriate model for acute inflammation with obstructive jaundice but long term survivors are no longer jaundiced. The LHML model was identified to be the most feasible model to study the effect of long-term obstructive jaundice. PMID:27916350

Voluntary and involuntary ligature of the bile duct in iatrogenic injuries: a nonadvisable approach.

PubMed

Mercado, Miguel Angel; Chan, Carlos; Jacinto, Juan Carlos; Sanchez, Norberto; Barajas, Alexandra

2008-06-01

Bile duct injuries related to laparoscopic and/or open cholecystectomy are a frequent finding and require surgical treatment. Complete obstruction is due to either intentionally or unintentionally placed ligatures or clips. The intentional application is usually performed to "facilitate identification of the duct by bile duct dilation." Considering that we are a national referral center for such injuries, we decided to analyze our cases of voluntary and involuntary duct ligation after iatrogenic bile duct injury. We reviewed the files of patients with voluntary or involuntary bile duct ligation. Results of preoperative evaluation of the ducts, operative treatment, and postoperative results were analyzed. A total of 413 patients were included. Forty-five patients presented with complete obstruction. In 15 cases, the ligature was intentional, and in 30 cases, occlusion was involuntary. Bile duct dilation (>10 mm) was demonstrated in one case of voluntary (6%) and three cases of involuntary ligations (10%). The remaining cases in both groups had no duct dilation and developed necrosis at the blinded duct and leakage proximal to the ligature, with different degrees of bilioperitoneum and/or biloma. In all cases, a Roux-en-Y hepatojejunostomy was performed. Bile duct ligature produces dilation in a very small number of patients (less than 10%) and usually produces necrosis of the blinded stump with subsequent bile leakage. Placement of a subhepatic drain and transference of the patient to a qualified center for reconstruction is the best approach if the primary surgeon is not able to do the repair.

Endoscopic Stent Placement in the Palliation of Malignant Biliary Obstruction

PubMed Central

2011-01-01

Biliary drainage with biliary stent placement is the treatment of choice for palliation in patients with malignant biliary obstruction caused by unresectable neoplasms. In such patients, the endoscopic approach can be initially used with percutaneous radiological intervention. In patients with unresectable malignant distal bile duct obstructions, endoscopic biliary drainage with biliary stent placement has now become the main and least invasive palliative modality, which has been proven to be more effective in >80% of cases with lower morbidity than surgery, and perhaps may provide a survival benefit. In patients with unresectable malignant hilar obstruction, the endoscopic approach for biliary drainage with biliary stent placement has also been considered as the treatment of choice. There is still a lack of clear consensus on the use of covered versus uncovered metal stents in malignant distal bile duct obstructions and plastic versus metal stents and unilateral versus bilateral drainage in malignant hilar obstructions. PMID:22741117

Diagnosing common bile duct obstruction: comparison of image quality and diagnostic performance of three-dimensional magnetic resonance cholangiopancreatography with and without compressed sensing.

PubMed

Kwon, Heejin; Reid, Scott; Kim, Dongeun; Lee, Sangyun; Cho, Jinhan; Oh, Jongyeong

2018-01-04

This study aimed to evaluate image quality and diagnostic performance of a recently developed navigated three-dimensional magnetic resonance cholangiopancreatography (3D-MRCP) with compressed sensing (CS) based on parallel imaging (PI) and conventional 3D-MRCP with PI only in patients with abnormal bile duct dilatation. This institutional review board-approved study included 45 consecutive patients [non-malignant common bile duct lesions (n = 21) and malignant common bile duct lesions (n = 24)] who underwent MRCP of the abdomen to evaluate bile duct dilatation. All patients were imaged at 3T (MR 750, GE Healthcare, Waukesha, WI) including two kinds of 3D-MRCP using 352 × 288 matrices with and without CS based on PI. Two radiologists independently and blindly assessed randomized images. CS acceleration reduced the acquisition time on average 5 min and 6 s to a total of 2 min and 56 s. The all CS cine image quality was significantly higher than standard cine MR image for all quantitative measurements. Diagnostic accuracy for benign and malignant lesions is statistically different between standard and CS 3D-MRCP. Total image quality and diagnostic accuracy at biliary obstruction evaluation demonstrates that CS-accelerated 3D-MRCP sequences can provide superior quality of diagnostic information in 42.5% less time. This has the potential to reduce motion-related artifacts and improve diagnostic efficacy.

Murine model of long-term obstructive jaundice.

PubMed

Aoki, Hiroaki; Aoki, Masayo; Yang, Jing; Katsuta, Eriko; Mukhopadhyay, Partha; Ramanathan, Rajesh; Woelfel, Ingrid A; Wang, Xuan; Spiegel, Sarah; Zhou, Huiping; Takabe, Kazuaki

2016-11-01

With the recent emergence of conjugated bile acids as signaling molecules in cancer, a murine model of obstructive jaundice by cholestasis with long-term survival is in need. Here, we investigated the characteristics of three murine models of obstructive jaundice. C57BL/6J mice were used for total ligation of the common bile duct (tCL), partial common bile duct ligation (pCL), and ligation of left and median hepatic bile duct with gallbladder removal (LMHL) models. Survival was assessed by Kaplan-Meier method. Fibrotic change was determined by Masson-Trichrome staining and Collagen expression. Overall, 70% (7 of 10) of tCL mice died by day 7, whereas majority 67% (10 of 15) of pCL mice survived with loss of jaundice. A total of 19% (3 of 16) of LMHL mice died; however, jaundice continued beyond day 14, with survival of more than a month. Compensatory enlargement of the right lobe was observed in both pCL and LMHL models. The pCL model demonstrated acute inflammation due to obstructive jaundice 3 d after ligation but jaundice rapidly decreased by day 7. The LHML group developed portal hypertension and severe fibrosis by day 14 in addition to prolonged jaundice. The standard tCL model is too unstable with high mortality for long-term studies. pCL may be an appropriate model for acute inflammation with obstructive jaundice, but long-term survivors are no longer jaundiced. The LHML model was identified to be the most feasible model to study the effect of long-term obstructive jaundice. Copyright © 2016 Elsevier Inc. All rights reserved.

Nasolacrimal drainage system cyst in an adult.

PubMed

Yamasoba, T; Sugimura, H

1996-01-01

A cyst of the nasolacrimal drainage system (NLDS) is rare in an adult. We report a case in a 29-year-old man of a mucous retention cyst of the NLDS, which appeared 2 years after the patient developed dacryocystitis coincident with an aggravation of chronic sinusitis. The lesion was successfully managed by removing the bony wall of the NLDS at the interface with the ethmoid and nasal cavity, as well as the membranous closure of the ostium of the common canaliculus. We speculate that the cyst development might have been initiated by inflammatory change such as mucosal adhesion in the NLDS resulting from the spread of secondary infection from the sinonasal tract.

Bile Cast Nephropathy Caused by Obstructive Cholestasis.

PubMed

Aniort, Julien; Poyet, Anaïs; Kemeny, Jean-Louis; Philipponnet, Carole; Heng, Anne-Elisabeth

2017-01-01

Acute kidney injury (AKI) is a major complication in patients with liver disease. Although hepatorenal syndrome is frequently involved, bile cast nephropathy, characterized by tubular bile cast formation, has been scarcely described in the setting of severe liver failure. Few renal histology studies are available in these patients. We describe a case of bile cast nephropathy in a patient with obstructive cholestasis caused by stones in the common bile duct. The kidney biopsy confirmed this diagnosis, with several green casts in tubular lumens, tubular injury, and bilirubin composition of the tubular casts with Hall stain. The patient had no confounding cause of kidney failure, and complete kidney recovery followed removal of the bile duct obstruction. This case shows that severe cholestasis is sufficient to cause AKI, and that AKI can be reversible after treatment of the biliary obstruction. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Update on endoscopic management of main pancreatic duct stones in chronic calcific pancreatitis.

PubMed

Choi, Eun Kwang; Lehman, Glen A

2012-03-01

Pancreatic duct stones are a common complication during the natural course of chronic pancreatitis and often contribute to additional pain and pancreatitis. Abdominal pain, one of the major symptoms of chronic pancreatitis, is believed to be caused in part by obstruction of the pancreatic duct system (by stones or strictures) resulting in increasing intraductal pressure and parenchymal ischemia. Pancreatic stones can be managed by surgery, endoscopy, or extracorporeal shock wave lithotripsy. In this review, updated management of pancreatic duct stones is discussed.

Effect of probiotic supplementation on bacterial translocation in common bile duct obstruction.

PubMed

Sarac, Fatma; Salman, Tansu; Gun, Feryal; Celik, Alaaddin; Gurler, Nezahat; Dogru Abbasoglu, Semra; Olgac, Vakur; Saygili, Ayse

2015-02-01

To investigate the effects of probiotics on bacterial translocation in the obstructive common bile duct with comparison to an enteral product containing arginine and glutamine. In our study, 40 Sprague-Dawley rats each weighing 250-300 g were used. Animals in Group 1 (sham) were laparatomized and fed standard chow supplemented with physiologic saline at daily doses of 2 ml through orogastric tube for 7 days. Common bile ducts of the animals in the other groups were ligated with 3/0 silk sutures. Group 2 (control group) was fed standard chow supplemented with daily doses of 2 ml physiologic saline. Group 3 (probiotic group) was fed standard chow supplemented with a probiotic solution (Acidophilus plus) containing strains of Lactobacillus acidophilus, Bifidobacterium bifidum and Lactobacillus bulgaricus at a daily doses of 2 × 10(9) colony forming units (CFU). Group 4 (formula group) was fed only an enteral solution (Stresson Multi Fiber) containing glutamine, arginine and a medium-chain fatty acid at daily doses of 2 g/kg. At the end of the 7th day, all animals were relaparatomized, and to determine bacterial translocation, aerobic, and anaerobic cultures were obtained from the specimens of mesenteric lymph nodes, intestinal mucosa, and blood samples. Smear cultures prepared from caecum were examined to determine the number of CFU. Finally, for histological examination specimens were excised from terminal ileum, and oxidative damage was assessed in liver tissues. Afterwards all animals were killed. Moderately lesser degrees of bacterial translocation, and mucosal damage were seen in Groups 3, and 4 relative to Group 2 (p < 0.05). In Group 4, any difference was not seen in the number of cecal bacteria relative to baseline values, while in Group 3, significant decrease in cecal colonization was seen. Among all groups, a significant difference between levels of malondialdehyde, and glutathione was not observed. At the end of our study, we have concluded that

Scanning Electron Microscopic Features of Nasolacrimal Silastic Stents Retained for Prolong Durations Following Dacryocystorhinostomy.

PubMed

Ali, Mohammad Javed; Baig, Farhana; Lakshman, Mekala; Naik, Milind N

2016-01-01

The aims of this study were to examine the scanning electron microscopic features of silastic nasolacrimal duct stents retained for long durations following a dacryocystorhinostomy. A prospective interventional study was performed on stents retrieved from patients who were lost to follow up after a dacryocystorhinostomy with Crawford stent insertion. Long duration was defined as stents retrieved at a minimum of 1 year following a dacryocystorhinostomy. None of the patients had any evidence of postoperative infection. After removal, the stent segments were subjected to biofilm and physical deposit analysis using standard protocols of scanning electron microscopy. These stent segments were compared against sterile stents which acted as controls. A total of 7 stents were studied. Five were consecutive patient samples, and 2 were sterile stents. All the 5 stents were retrieved from patients who were lost to follow up for a minimum of 12 months following surgery. The mean duration of intubation at retrieval was 21 months. All the stents demonstrated evidence of biofilm formation and physical deposits. However, as the duration of retention increased, the deposits and biofilms were noted to be progressively denser, multilayered and extensive. Certain areas demonstrated thick biofilm integration with the deposits. Polymicrobial communities were noted within the exopolysaccharide matrix. This is the first study to exclusively report on scanning electron microscopic features of lacrimal stents retained for long durations. Further studies on physical elements within the deposits and protein analysis would provide more insights into stent-tissue interactions.

Neonatal prolapsed patent vitellointestinal duct.

PubMed

Patel, Ramnik V; Kumar, Hemant; Sinha, C K; Patricolo, Mario

2013-07-10

A case of a prolapsed patent vitellointestinal duct (PVID) in a 10-day-old neonate who presented with vomiting and poor weight gain with partial intestinal obstruction and a flower like pink, prolapsing lesion at his umbilicus has been reported. A limited contrast study through the tubular structure confirmed it to be a PVID. He underwent transumbilical exploration and resection and anastomosis uneventfully. Persistence of the vitellointestinal duct as a whole or part of it leads to a wide variety of anomalies-Meckel's diverticulum is the commonest lesion and a PVID is the rarest. Umbilical cord clamping flush with the abdominal wall may convert a Meckel's diverticulum prolapsing in the base of umbilical ring into a PVID. Careful assessment should be made for associated anomalies. Transumbilical exploration gives the best cosmetic and functional results.

Agenesis of the gallbladder with hypoplastic cystic duct diagnosed at laparoscopy.

PubMed

Kwon, A-Hon; Yanagimoto, Hiroaki; Matsui, Yoichi; Imamura, Atsushi

2006-08-01

An 86-year-old man was admitted to our department with complaints of intermittent upper abdominal pain. Ultrasonography of the abdomen showed dilated extrahepatic bile ducts containing stones; however, the gallbladder was not clearly identified. Magnetic resonance cholangiopancreatography showed dilated extrahepatic ducts and choledocholithiasis without gallbladder visualization. The stone extraction was performed with endoscopic sphincterotomy. Three-dimensional images using spiral-computed tomography after intravenous-infusion cholangiography clearly demonstrated an obstruction of the cystic duct. The patient was scheduled for laparoscopic cholecystectomy. At laparoscopy, the gallbladder fossa was not identified on the undersurface of the liver. Despite a thorough examination of the intrahepatic (left-sided within the lesser omentum), retroperitoneal, retrohepatic (within the falciform ligament), retroduodenal, and retropancreatic areas using laparoscopic ultrasonography, the gallbladder was not found. After careful dissection of the hepatoduodenal ligament, the dilated extrahepatic bile duct and a 1-cm length of hypoplastic cystic duct were found. Gallbladder agenesis is usually accompanied by the lack of the cystic duct. The present case is the third report of gallbladder agenesis with a patent or hypoplastic cystic duct.

Intraductal papillary neoplasm originating from an anomalous bile duct.

PubMed

Maki, Harufumi; Aoki, Taku; Ishizawa, Takeaki; Tanaka, Mariko; Sakatani, Takashi; Beck, Yoshifumi; Hasegawa, Kiyoshi; Sakamoto, Yoshihiro; Kokudo, Norihiro

2017-04-01

An 82-year-old woman who had been suffering from repeated obstructive jaundice for 7 years was referred to our hospital. Although endoscopic aspiration of the mucin in the common bile duct had been temporally effective, origin of the mucin production had not been detectable. The patient thus had been forced to be on long-term follow-up without curative resection. Endoscopic retrograde cholangioscopy on admission revealed massive mucin in the common bile duct. In addition, an anomalous bile duct located proximal to the gallbladder was identified. Since the lumen of the anomalous duct was irregular and the rest of biliary tree was completely free of suspicious lesions, the anomalous duct was judged to be the primary site. Surgical resection of the segment 4 and 5 of the liver combined with the extrahepatic biliary tract was performed. Pathological diagnosis was compatible to intraductal papillary neoplasm with high-grade intraepithelial dysplasia of the anomalous bile duct. The patient has been free from the disease for 6.5 years after resection. This is the first case of intraductal papillary neoplasm derived from an anomalous bile duct, which was resected after long-term conservative treatment. The present case suggested the slow growing character of natural history of the neoplasm.

Generation of Higher Order Modes in a Rectangular Duct

NASA Technical Reports Server (NTRS)

Gerhold, Carl H.; Cabell, Randolph H.; Brown, Donald E.

2004-01-01

Advanced noise control methodologies to reduce sound emission from aircraft engines take advantage of the modal structure of the noise in the duct. This noise is caused by the interaction of rotor wakes with downstream obstructions such as exit guide vanes. Mode synthesis has been accomplished in circular ducts and current active noise control work has made use of this capability to cancel fan noise. The goal of the current effort is to examine the fundamental process of higher order mode propagation through an acoustically treated, curved duct. The duct cross-section is rectangular to permit greater flexibility in representation of a range of duct curvatures. The work presented is the development of a feedforward control system to generate a user-specified modal pattern in the duct. The multiple-error, filtered-x LMS algorithm is used to determine the magnitude and phase of signal input to the loudspeakers to produce a desired modal pattern at a set of error microphones. Implementation issues, including loudspeaker placement and error microphone placement, are discussed. Preliminary results from a 9-3/8 inch by 21 inch duct, using 12 loudspeakers and 24 microphones, are presented. These results demonstrate the ability of the control system to generate a user-specified mode while suppressing undesired modes.

Endoscopic dacryocystorhinostomy without silicone stent.

PubMed

Yeon, Je Yeob; Shim, Woo Sub

2012-06-01

In nasolacrimal duct (NLD) obstruction patients that undergo endoscopic dacryocystorhinostomy (DCR), creation of a patent rhinostomy with adequate epithelialization can be accomplished without a stent. However, in common canalicular obstruction patients, a silicone stent seems to have a beneficial role and to bear more favorable results. The aim of this study was to evaluate the surgical outcome of endoscopic DCR without the use of a silicone stent. In all, 36 patients (41 eyes) who underwent endoscopic DCR were enrolled in this study. The patients were classified into a DCR with silicone stent group and a DCR without silicone stent group. Then each of the groups was subdivided into common canalicular obstruction group and NLD obstruction group. Surgical outcomes were evaluated by postoperative symptom improvement and patency of the rhinostomy under nasal endoscopic exam. The epiphora was improved in 84.2% of the silicone stent group and 81.8% of the non-silicone stent group. Categorized by the level of obstruction, in common canalicular obstruction, the success rate was 84.5% (11/13) in the silicone stent group and 57.1% (4/7) in the no stent group. In NLD obstruction, the success rate was 83.0% (5/6) in the silicone stent group and 93.3% (14/15) in the no stent group.

Neonatal prolapsed patent vitellointestinal duct

PubMed Central

Patel, Ramnik V; Kumar, Hemant; Sinha, C K; Patricolo, Mario

2013-01-01

A case of a prolapsed patent vitellointestinal duct (PVID) in a 10-day-old neonate who presented with vomiting and poor weight gain with partial intestinal obstruction and a flower like pink, prolapsing lesion at his umbilicus has been reported. A limited contrast study through the tubular structure confirmed it to be a PVID. He underwent transumbilical exploration and resection and anastomosis uneventfully. Persistence of the vitellointestinal duct as a whole or part of it leads to a wide variety of anomalies–Meckel's diverticulum is the commonest lesion and a PVID is the rarest. Umbilical cord clamping flush with the abdominal wall may convert a Meckel's diverticulum prolapsing in the base of umbilical ring into a PVID. Careful assessment should be made for associated anomalies. Transumbilical exploration gives the best cosmetic and functional results. PMID:23845681

Obstructive parotitis secondary to an acute masseteric bend.

PubMed

Reddy, Ryan; White, David R; Gillespie, M Boyd

2012-01-01

To investigate 3 cases of chronic parotitis secondary to an acute bend in Stensen's duct caused by an enlargement of the masseteric space. Three female patients presented with symptoms consistent with obstructive parotitis including glandular swelling and tenderness during meals. A 10-year-old patient had unilateral facial swelling with enlargement of the masseter muscle and mandible later diagnosed as fibrous dysplasia. Salivary endoscopy showed an acute bend in Stensen's duct secondary to a mass effect. The patient's parotid swelling resolved following debulking of the mandibular mass and sialendoscopy with irrigation. Two adult patients with bilateral parotid involvement presented with bilateral masseteric hypertrophy and dental wear facets consistent with bruxism. Salivary endoscopy revealed bilateral kinking of Stensen's duct with jaw closure. Both patients improved symptomatically following nightly bite guard use and ultrasound-guided Botox injections of the masseter muscle and parotid. Obstructive parotitis is rarely caused by an acute masseteric bend. Diagnosis of a kinking Stensen's duct is aided with salivary endoscopy and imaging to determine the precipitating pathology. In the case of masseteric hypertrophy, symptomatic improvement can be achieved with Botox-induced atrophy of masseteric hypertrophy or with surgical reduction for associated fibrous dysplasia. Copyright © 2011 S. Karger AG, Basel.

Alcohol-induced chronic pancreatitis in rats after temporary occlusion of biliopancreatic ducts with Ethibloc.

PubMed

Pap, A; Boros, L

1989-01-01

Chronic obstructive pancreatitis-like histological and biochemical alterations were provoked in male Wistar rats with Ethibloc occlusion of the common bile duct and the main pancreatic ducts. After the disappearance of the glue from the ducts, a gradual and almost total recovery was demonstrated during a 2-month observation period. About 12 g/kg of alcohol (20% vol/vol) given daily by gastric intubation and ad libitum intake inhibited the recovery of pancreatic weight and enzyme contents in the occluded rats, and within a 2-month period chronic calcifying-type pancreatitis became evident with some signs of remaining obstructive pancreatitis-like lesions. Cessation of alcohol administration after 2 months resulted in a recovery of pancreatic weight and enzyme contents, although morphological regeneration was less pronounced and calcification remained visible in some rats. A 50% raw soy flour diet provoked some further changes in the proportion of enzymes without any supplementary increases of pancreatic weight and protein content. This animal model of chronic pancreatitis demonstrates that chronic obstructive and calcifying pancreatitis can appear together and earlier if the etiological factors act in combination. Suppression of pancreatic regeneration by alcohol seems to be necessary to maintain chronic pancreatitis-like lesions and to develop calcification.

Endoscopic modified medial maxillectomy for treatment of inverted papilloma originating from the maxillary sinus.

PubMed

Erbek, Selim S; Koycu, Alper; Buyuklu, Fuat

2015-05-01

Endoscopic approaches have become an alternative to external approaches in the treatment of sinonasal inverted papillomas (IPs) in recent years. The aim of this study was to analyze the outcomes of endoscopic modified medial maxillectomy preserving the nasolacrimal duct and the inferior turbinate in selected IP cases. Medical charts of patients diagnosed with IP originating from the maxillary sinus between July 2008 and August 2013 were reviewed. Eight patients who had undergone endoscopic modified medial maxillectomy were included in the study. Attachment of IP was located on the medial wall of the maxillary sinus in all cases. The nasolacrimal duct was preserved in all of the patients. The inferior turbinate was completely preserved in 5 patients, and the anterior part of the inferior turbinate was preserved in 3 patients. The mean follow-up period of the patients was 30.8 months (12-60  mo). None of the patients had recurrence or major complications. The postoperative complaints were minor hemorrhagic discharge and crusting for the first few weeks. Endoscopic modified medial maxillectomy preserving the nasolacrimal duct and the inferior turbinate provides good surgical and functional outcomes in selected IP cases.

Spontaneous remission of obstructive jaundice in rats: Selection of experimental models

PubMed Central

Lv, Yunfu; Yue, Jie; Gong, Xiaoguang; Han, Xiaoyu; Wu, Hongfei; Deng, Jie; Li, Yejuan

2018-01-01

The aim of the present study was to evaluate the prevalence and causes of spontaneous remission of obstructive jaundice in rats. Healthy male and female Wistar rats (180–220 g) were randomly assigned to receive common bile duct ligation (CBDL) and transection (group A), CBDL only (group B), or CBD dissection without ligation or transection (control group C; n=36 in each group). There was a difference in eye and skin jaundice prevalence between groups A and B from 14 days after surgery. The level of total bilirubin (TB) did not continue to increase in group A and began to decrease in the majority of rats in group B (P<0.05 vs. group B). At day 21 after surgery, the TB level returned to normal in group B and no significant difference was observed compared with group C. At day 21 after surgery, significant dilatation of bile ducts above the ligature was observed in group A following cholangiography with 38% meglumine diatrizoate and this contrast agent did not spread to other sites. Slight dilatation of the proximal bile ducts was observed in group B and the contrast agent entered the intestinal lumen through the omental ducts adhering to the porta hepatis. After 14 days of surgery, there were 36 rats in group A and B, and 17 rats exhibited spontaneous regression of jaundice. Overall, 47.2% (17/36) of rats experienced spontaneous remission of obstructive jaundice, 82.4% (14/17) of which underwent ligation only. The spontaneous remission of jaundice may have been caused by shunting through very small bile ducts or omental ducts adhering to the porta hepatis. If a model of biliary obstruction is to be established in future research, a model of CBDL and transection is preferable. In this case, jaundice reduction surgery should be performed 14 days after establishment of the model. PMID:29904412

Endoscopic versus surgical drainage of the pancreatic duct in chronic pancreatitis.

PubMed

Cahen, Djuna L; Gouma, Dirk J; Nio, Yung; Rauws, Erik A J; Boermeester, Marja A; Busch, Olivier R; Stoker, Jaap; Laméris, Johan S; Dijkgraaf, Marcel G W; Huibregtse, Kees; Bruno, Marco J

2007-02-15

For patients with chronic pancreatitis and a dilated pancreatic duct, ductal decompression is recommended. We conducted a randomized trial to compare endoscopic and surgical drainage of the pancreatic duct. All symptomatic patients with chronic pancreatitis and a distal obstruction of the pancreatic duct but without an inflammatory mass were eligible for the study. We randomly assigned patients to undergo endoscopic transampullary drainage of the pancreatic duct or operative pancreaticojejunostomy. The primary end point was the average Izbicki pain score during 2 years of follow-up. The secondary end points were pain relief at the end of follow-up, physical and mental health, morbidity, mortality, length of hospital stay, number of procedures undergone, and changes in pancreatic function. Thirty-nine patients underwent randomization: 19 to endoscopic treatment (16 of whom underwent lithotripsy) and 20 to operative pancreaticojejunostomy. During the 24 months of follow-up, patients who underwent surgery, as compared with those who were treated endoscopically, had lower Izbicki pain scores (25 vs. 51, P<0.001) and better physical health summary scores on the Medical Outcomes Study 36-Item Short-Form General Health Survey questionnaire (P=0.003). At the end of follow-up, complete or partial pain relief was achieved in 32% of patients assigned to endoscopic drainage as compared with 75% of patients assigned to surgical drainage (P=0.007). Rates of complications, length of hospital stay, and changes in pancreatic function were similar in the two treatment groups, but patients receiving endoscopic treatment required more procedures than did patients in the surgery group (a median of eight vs. three, P<0.001). Surgical drainage of the pancreatic duct was more effective than endoscopic treatment in patients with obstruction of the pancreatic duct due to chronic pancreatitis. (Current Controlled Trials number, ISRCTN04572410 [controlled-trials.com].). Copyright 2007

Intraductal endoscopic radiofrequency ablation for the treatment of hilar non-resectable malignant bile duct obstruction

PubMed Central

Tal, Andrea Oliver; Vermehren, Johannes; Friedrich-Rust, Mireen; Bojunga, Jörg; Sarrazin, Christoph; Zeuzem, Stefan; Trojan, Jörg; Albert, Jörg Gerhard

2014-01-01

AIM: To evaluate the safety and technical success of endoscopic radiofrequency ablation (RFA) for palliative treatment of malignant hilar bile duct obstruction. METHODS: In this study, a recently CE and FDA-approved endoscopic RFA catheter was first tested in an ex vivo pig liver model to study the effect of electrosurgical variables on the extent of the area of induced necrosis. Subsequently, a retrospective analysis was conducted of all patients treated with endoscopic RFA for malignant biliary obstruction at our center between February 2012 and April 2013. All patients received an additional plastic stent implantation into the biliary tree following RFA. RESULTS: In the pig model, ablation time of 60-90 seconds using the bipolar soft coagulation mode at 8-10 watts with an effect of 8 was found to be the most feasible setting. Twelve patients (5 females, 7 males; mean age, 70 years) underwent 19 endoscopic RFA (range, 1-5) sessions. Deployment of RFA was successful in all patients. Systemic chemotherapy was administered in four patients. We observed biliary bleeding 4-6 wk after the intervention in three cases and two of these patients died: in one patient, spontaneous hemobilia occurred, whereas bleeding started during stent extraction in the other. In the third patient, bleeding was stopped by insertion of a non-covered self-expanding metal stent. Another three patients developed cholangitis during follow-up. Seven patients died during follow-up and median survival was 6.4 mo (95%CI: 0.05-12.7) from the time of the first RFA. CONCLUSION: Endoscopic RFA is an easy to perform and technically highly successful procedure. However, hemobilia possibly associated with RFA occurred in three of our patients. Therefore, larger prospective studies are needed to further evaluate the safety and efficacy of this promising new method. PMID:24527176

[A case of fascioliasis in the intrahepatic duct with concurrent clonochiasis].

PubMed

Kim, Seung-Hyun; Jung, Chang-Kil; Her, Jin; Hur, Ki-Hwan; Choi, Jae-Hyuc; Kang, Kee-Hoon; Hwang, Chan-Hee

2014-11-01

The main causes of biliary obstruction are stones and cancers. Fascioliasis is a very rare case which causes biliary obstruction. Fascioliasis is a zoonosis caused by Fasciola hepatica which infects herbivores like sheep and cattle. F. hepatica lives in the biliary system or the liver parenchyma of a host. In Korea, the occurrence of this infection in human is very rare and only few cases have been reported. A 32-year-old male presented with upper abdominal pain and jaundice. His laboratory finding revealed elevated liver transaminases. Abdomen CT scan showed mild left intrahepatic bile duct dilatation. On ERCP, adult F. hepatica worms were found and were thus removed. Concurrently, clonorchiasis was diagnosed by stool exam and serologic enzyme-linked immunosorbent assay test. Clonorchiasis was treated with praziquantel. Herein, we report a case of intrahepatic bile duct dilatation due to F. hepatica infection with concurrent Clonorchis sinensis infestation.

Pancreatobiliary fistula associated with intraductal papillary mucinous carcinoma accompanying obstructive jaundice: A case report.

PubMed

Komo, Toshiaki; Oishi, Koichi; Kohashi, Toshihiko; Hihara, Jun; Kanou, Mikihiro; Nakashima, Akira; Kaneko, Mayumi; Mukaida, Hidenori; Hirabayashi, Naoki

2018-06-04

Intraductal papillary mucinous neoplasms (IPMNs) occasionally involve formation of fistulas with other adjacent organs. Pancreatobiliary fistulas associated with IPMNs are rare, but affected patients often develop obstructive jaundice and cholangitis. A 79-year-old man was referred to our hospital for evaluation of abnormal biliary enzymes. Contrast-enhanced computed tomography and endoscopic retrograde cholangiopancreatography demonstrated multiple cystic lesions with septa in the pancreatic head and fistulas between the cystic lesions and common bile duct. The clinical diagnosis was pancreatobiliary fistula associated with a mixed-type IPMN and accompanying obstructive jaundice. The patient underwent subtotal stomach-preserving pancreaticoduodenectomy. The resected specimen showed fistulas between the cystic lesions and common bile duct. Histopathological examination showed that the main and branch ducts of the pancreatic head were dilated and filled with mucus. The epithelia of the pancreatic ducts revealed papillary proliferation and an invasive adenocarcinoma arising from an intraductal neoplasm. Immunohistochemistry examination showed CDX2- and MUC2-positive reactions. The final diagnosis was an intraductal papillary mucinous carcinoma of the intestinal-type. The patient remained disease-free for 9 months postoperatively. The causes of death in patients who have pancreatobiliary fistulas associated with IPMNs without resection are cholangitis or hepatic insufficiency. Nonoperative treatment is limited for cases with obstructive jaundice. It is necessary to prevent obstructive jaundice and cholangitis due to a large quantity of mucinous material. Surgical resection should be considered, if possible, in patients with pancreatobiliary fistulas associated with IPMNs. A better prognosis is expected with prevention of obstructive jaundice or cholangitis. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Detection of memory loss of symmetry in the blockage of a turbulent flow within a duct

NASA Astrophysics Data System (ADS)

Santos, F. Rodrigues; da Silva Costa, G.; da Cunha Lima, A. T.; de Almeida, M. P.; da Cunha Lima, I. C.

This paper aims to detect memory loss of the symmetry of blockades in ducts and how far the information on the asymmetry of the obstacles travels in the turbulent flow from computational simulations with OpenFOAM. From a practical point of view, it seeks alternatives to detect the formation of obstructions in pipelines. The numerical solutions of the Navier-Stokes equations were obtained through the solver PisoFOAM of the OpenFOAM library, using the large Eddy simulation (LES) for the turbulent model. Obstructions were placed near the duct inlet and, keeping the blockade ratio fixed, five combinations for the obstacles sizes were adopted. The results show that the information about the symmetry is preserved for a larger distance near the ducts wall than in mid-channel. For an inlet velocity of 5m/s near the walls the memory is kept up to distance 40 times the duct width, while in mid-channel this distance is reduced almost by half. The maximum distance in which the symmetry breaking memory is preserved shows sensitivity to Reynolds number variations in regions near the duct walls, while in the mid channel that variations do not cause relevant effects to the velocity distribution.

Surgical treatment of chronic pancreatitis with pancreatic main duct dilatation: Long term results after head resection and duct drainage

PubMed Central

Schwarz, A.; Beger, H. G.

2005-01-01

Tissue and duct hypertension is considered as a major factor in the etiology of pain in patients with chronic pancreatitis (CP). Duct dilatation is a consequence of duct obstruction due to scars or duct stones. Nevertheless, the procedure of choice, drainage or resection, is still under discussion. We present long-term results of patients operated with duodenum-preserving pancreatic head resection (DPPHR) combined with a Partington-Rochelle duct drainage in cases of chronic pancreatitis with multiple stenosis and dilatation of the side ducts. Methods and patients. From April 1982 to September 2001, in 55 out of 538 patients with chronic pancreatitis, a DPPHR with additionally Partington-Rochelle duct drainage was performed (44 male, 11 female, mean age 45.8 years). Ninety-two percent of the patients suffered from alcoholic pancreatitis. Medical respective pain treatment for chronic pancreatitis was in median 64.5 months prior to surgery. The indications for surgery were in 87% pain, 59% of the patients had an inflammatory mass in the head of the pancreas, 36% a common bile duct stenosis and 5% a severe stenosis of the duodenum. The endocrine function (OGGT) was impaired in 79% of the patients preoperatively. Results. Hospital mortality was 0%, postoperative complications occurred in 11 patients. Follow-up: All except 2 patients were followed up in the outpatient clinic with the mean follow-up time of 69.7 months (8–105 months), the late mortality was 9%. Sixty-eight percent of the patients were completely free of pain, 29% had occasional pain, 3% suffered from a further attack of pancreatitis. Body weight increased in 79%, 58% were professionally rehabilitated. Late postoperative endocrine function was unchanged in 85% (improved in 5%, deteriorated in 10%). Conclusion. The pain control in patients with multiple duct stenosis after duodenum-preserving pancreatic head resection with duct drainage leads to long-standing absence of pain and low recurrence rate of

Castleman disease presenting as obstructive jaundice.

PubMed

Al-Salamah, Saleh M; Khan, Iftikhar A; Khalid, Kamran; Al-Shakweer, Wafaa A

2005-01-01

A 48-year-old Saudi male was admitted with features of obstructive jaundice. Endoscopic retrograde cholangiopancreatography showed stricture in distal common bile duct CBD. Computed tomography scan revealed lymphadenopathy along CBD and in porta hepatis. Cholangiocarcinoma, lymphoma or metastatic deposits were suspected but no definite preoperative diagnosis could be established. Laparotomy disclosed lymph node enlargement in porta hepatis and along the CBD and lesser curvature of the stomach. Triple bypass procedure was performed to relieve the obstruction. Pathological examination of the lymph nodes showed Castleman disease of hyaline vascular type.

Intralacrimal migration of Masterka® stents.

PubMed

Fayet, B; Racy, E; Katowitz, W R; Katowitz, J A; Ruban, J-M; Brémond-Gignac, D

2018-03-01

Tearing and conjunctivitis in children are commonly due to lacrimal drainage system obstruction. Congenital nasolacrimal obstruction is a common pathology treated by probing with or without silicone stent insertion, depending upon the age of the child. The silicone stent is self-retaining and placed for at least one month. Masterka ® is a recent version of Monoka ® , which may lead to the same surgical complications, such as intralacrimal migration. The medical records of two patients surgically treated with the Masterka ® probe for nasolacrimal duct obstruction, who developed intralacrimal migration of the stent, were retrospectively reviewed and analyzed. A 41-month-old child and an 18-month-old child presented with disappearance of the silicone tube after 7 days and 2 years respectively. In the first case, the tube migrated completely within the lacrimal system and became externalized through the nose at 2 years, while in the second case, the Masterka ® was retrieved through a canalicular approach. In both cases, infants had no further tearing. The frequency self-retaining stent disappearance is estimated at 15%. Among these cases, intralacrimal migration is only reported in 0.5% of cases. To prevent intralacrimal migration, the surgical technique must follow a certain number of rules. Management, based on residual epiphora, is discussed. Prevention of intralacrimal migration of self-retaining stents involves a rigorous analysis of the relationship between the meatus and the fixation head at the time of placement. After lacrimal intubation, scheduled monitoring is necessary to screen for stent disappearance. Management is based on clinical findings, anterior rhinoscopy and even exploratory canaliculotomy. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Duodenal Loop Obstruction as an Unusual Cause of Acute Pancreatitis: A Case Series.

PubMed

Lee, Hyeonmin; Choi, Yonghyeok; Jeong, Hyewon; Lim, Jae Kyu; Jung, Taeyoung; Han, Joung Ho; Park, Seon Mee

2016-12-25

Duodenal loop obstruction is an unusual cause of acute pancreatitis. Increased intraluminal pressure hinders pancreatic flow, causing dilatation of the pancreatic duct and inducing acute pancreatitis. We experienced three cases of acute pancreatitis that resulted from duodenal loop obstruction after (1) an esophagectomy with gastric pull-up procedure for esophageal cancer, (2) a gastrectomy with Billroth I reconstruction for gastric cancer, and (3) a gastrojejunostomy for abdominal trauma. An abdominal CT scan revealed a distended duodenal loop, dilated pancreatic duct, and inflamed pancreas with fluid collection. Acute pancreatitis with duodenal loop obstruction was diagnosed by abdominal pain, elevated serum amylase/lipase, and abdominal CT findings. Immediate decompression with a nasogastric tube was performed, and all patients showed improvement within one week after admission. Each patient was followed up for more than two years without recurrence. Our findings suggest the usefulness of nasogastric tube decompression as the first line of treatment for acute pancreatitis related to duodenal loop obstruction.

Protective effects of intravenous anesthetics on kidney tissue in obstructive jaundice

PubMed Central

Hatipoglu, Sinan; Yildiz, Huseyin; Bulbuloglu, Ertan; Coskuner, Ismail; Kurutas, Ergul Belge; Hatipoglu, Filiz; Ciralik, Harun; Berhuni, Mehmet Sait

2014-01-01

AIM: To evaluate the protective effects on kidney tissue of frequently used intravenous anesthetics (ketamine, propofol, thiopental, and fentanyl) in rats with obstructive jaundice. METHODS: There is an increased incidence of postoperative acute renal failure in patients with obstructive jaundice. Thirty-two Wistar-albino rats were randomly divided into four equal groups. Laparatomy was performed on each animal in the four groups and common bile ducts were ligated and severed on day 0. After 7 d, laparotomy was again performed using ketamine, propofol, thiopental, or fentanyl anesthesia whose antioxidative properties are well known in oxidative stress in a rat liver model of obstructive jaundice. After 2 h, the rats were sacrificed. Renal tissue specimens were analyzed for catalase, superoxide dismutase and malondialdehyde enzymes activities. All values are expressed as the mean ± SD. P values less than 0.05 were considered statistically significant. RESULTS: All animals survived without complications until the end of the study. Enlargement in the bile duct and obstructive jaundice were observed in all rats. Catalase was found to be significantly lower in the fentanyl group than in the ketamine (P = 0.039), propofol (P = 0.012), and thiopental (P = 0.001) groups. Superoxide dismutase activities were similar in all groups (P > 0.05). Malondialdehyde was found to be significantly lower in the ketamine group than in the propofol (P = 0.028), thiopental (P = 0.002) and fentanyl (P = 0.005) groups. Malondialdehyde was also lower in the fentanyl group than in the thiopental group (P = 0.001). The results showed that obstructive jaundice sensitizes renal tissue to damage under the different anesthetics. CONCLUSION: Among the agents tested, ketamine and propofol generated the least amount of oxidative stres on renal tissues in this rat model of obstructive jaundice created by common bile duct ligation. The importance of free radical injury in renal tissue in obstructive

Modified transnasal endoscopic medial maxillectomy through prelacrimal duct approach.

PubMed

Suzuki, Motohiko; Nakamura, Yoshihisa; Yokota, Makoto; Ozaki, Shinya; Murakami, Shingo

2017-10-01

We previously reported a modified endoscopic medial maxillectomy (modified transnasal endoscopic medial maxillectomy through prelacrimal duct approach [MTEMMPDA]) to resect inverted papilloma (IP), for which the inferior turbinate (IT) and nasolacrimal duct (ND) can be preserved. MTEMMPDA is a safe and effective method to obtain wide, straight access to the maxillary sinus (MS). However, there are few reported cases of patients who underwent MTEMMPDA, and even fewer of patients who underwent partial osteotomy of the apertura piriformis and the anterior wall of the MS. In this study, we analyzed the outcomes of 51 patients who underwent MTEMMPDA. Retrospective review. All patients who underwent MTEMMPDA at our hospital between January 2004 and December 2015 were included in this study. Fifty-one patients with sinonasal IP in the MS underwent MTEMMPDA. Recurrence was seen in the MS of one patient (follow-up of 2-138 months). The IT remained unchanged in all 51 patients without atrophy. We have not observed epiphora, eye discharge, dry nose, or persistent crusting after this surgery. Although seven patients had numbness around the upper lip after surgery, this had disappeared by 1 year after surgery. Additional partial osteotomy of the apertura piriformis and the anterior wall of the MS were done in eight patients. Deformation of the external nose was not seen. This approach appears to be a safe and effective method to resect IP in the MS, even if there is additional partial osteotomy of the apertura piriformis and the anterior wall of the MS. 4. Laryngoscope, 127:2205-2209, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Endoscopic stenting in bile duct cancer increases liver volume.

PubMed

Lee, Chang Hun; Kim, Seong Hun; Kim, In Hee; Kim, Sang Wook; Lee, Soo Teik; Kim, Dae Ghon; Yang, Jae Do; Yu, Hee Chul; Cho, Baik Hwan; Lee, Seung Ok

2014-09-01

Objective evaluation tools for assessing the effectiveness of stenting in palliative treatment of malignant biliary obstruction are not satisfactory. Effects of biliary stenting on liver volume change have never been studied. We aimed to use volumetry to analyze liver volume changes after endoscopic stenting in bile duct cancer according to the location and number of stents. Retrospective review. University hospital. Patients with a diagnosis of hilar or distal bile duct cancer and who underwent biliary metal stenting. ERCP with self-expandable metal stent placement. Liver volume change after biliary stenting and its comparison according to the location (hilar vs distal common bile duct) and number (hilar bilateral vs hilar unilateral). There were 60 patients; 31 were treated for hilar bile duct cancer (13 for bilateral stent and 18 for unilateral stent) and 29 for distal bile duct cancer. Overall mean follow-up duration was 11.7 ± 4.9 weeks. Liver volume increased 17.4 ± 24.1%. The rate of liver growth was rapid during the early period from 4 to 8 weeks. Stenting in hilar bile duct cancer tended to increase liver volume more than distal biliary stents (22.5% vs 11.9%, P = .091). In hilar bile duct cancer, unilateral and bilateral stents showed similar liver volume increases (20.1% and 25.8%, respectively; P = .512). Single center, retrospective. Biliary stenting markedly increased liver volume in both hilar and distal bile duct cancer. Our data suggest that liver volume assessment could be a useful tool for evaluating stent efficacy. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Correlation between hepatobiliary scintigraphy and surgery or postmortem examination findings in dogs and cats with extrahepatic biliary obstruction, partial obstruction, or patency of the biliary system: 18 cases (1995-2004).

PubMed

Head, Laurie L; Daniel, Gregory B

2005-11-15

To evaluate the usefulness of serum biochemical variables and scintigraphic study results for differentiating between dogs and cats with complete extrahepatic biliary obstruction (EHO) and those with partial EHO or patent bile ducts. Retrospective case series. 17 dogs and 1 cat. Animals that underwent hepatobiliary scintigraphy and had either surgical or postmortem confirmation of the degree of bile duct patency were included. Scintigraphic images were evaluated and biliary tracts were classified as patent, partially obstructed but patent, or obstructed. Surgery or postmortem examination was considered the gold standard for diagnosis, and compared with those findings, sensitivity and specificity of scintigraphy were calculated. With absence of radioactivity in the intestinal tract as the diagnostic criterion for EHO, the sensitivity and specificity of scintigraphic diagnosis were both 83% when final images were acquired at 19 to 24 hours, compared with 100% and 33%, respectively, when 180 minutes was used as the cutoff time. Animals with partial biliary obstruction had less intestinal radioactivity that arrived later than that observed in animals with patent biliary tracts. Animals in which intestinal radioactivity has not been observed after the standard 3 to 4 hours should undergo additional scintigraphic imaging. Findings in animals with partial biliary obstruction include delayed arrival of radioactivity and less radioactivity in the intestine. Distinguishing between complete and partial biliary tract obstruction is important because animals with partial obstruction may respond favorably to medical management and should not be given an erroneous diagnosis of complete obstruction.

A Pilot Study of Common Bile Duct Reconstruction with CorMatrix Extracellular Matrix in Swine (Sus scrofa)

DTIC Science & Technology

2015-02-06

additional pages if necessary.) PROTOCOL#: FDG20140008A DATE: 6 February 2015 PROTOCOL TITLE: A Pilot Study of Common Bile Duct Reconstruction with...obstruction or bile peritonitis. This was reported to the IACUC chair. 9. REDUCTION, REFINEMENT, OR REPLACEMENT OF ANIMAL USE; REPLACEMENT...benefit the DoD/USAF? We developed a porcine model of common bile duct injury and interposition grafting, gained experience managing these patients

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

PubMed

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

2013-01-10

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

Effect of L-cysteine on remote organ injury in rats with severe acute pancreatitis induced by bile-pancreatic duct obstruction.

PubMed

Yang, Li-Juan; Wan, Rong; Shen, Jia-Qing; Shen, Jie; Wang, Xing-Peng

2013-08-01

Remote organ failure occurs in cases of acute pancreatitis (AP); however, the reports on AP induced by pancreatic duct obstruction are rare. In this study we determined the effect of L-cysteine on pancreaticobiliary inflammation and remote organ damage in rats after pancreaticobiliary duct ligation (PBDL). AP was induced by PBDL in rats with 5/0 silk. Sixty rats were randomly divided into 4 groups. Groups A and B were sham-operated groups that received injections of saline or L-cysteine (10 mg/kg) intraperitoneally (15 rats in each group). Groups C and D were PBDL groups that received injections of saline or L-cysteine (10 mg/kg) intraperitoneally (15 rats in each group). The tissue samples of the pancreas and remote organs such as the lung, liver, intestine and kidney were subsequently examined for pathological changes under a light microscope. The samples were also stored for the determination of malondialdehyde and glutathione levels. Blood urea nitrogen (BUN), plasma amylase, ALT and AST levels were determined spectrophotometrically using an automated analyzer. Also, we evaluated the effect of L-cysteine on remote organ injury in rats with AP induced by retrograde infusion of 3.5% sodium taurocholate (NaTc) into the bile-pancreatic duct. Varying degrees of injury in the pancreas, lung, liver, intestine and kidney were observed in the rats 24 hours after PBDL. The severity of injury to the lung, liver and intestine was attenuated, while injury status was not changed significantly in the pancreas and kidney after L-cysteine treatment. Oxidative stress was also affected by L-cysteine in PBDL-treated rats. The concentration of tissue malondialdehyde decreased in the pancreas and remote organs of PBDL and L-cysteine administrated rats, and the concentration of glutathione increased more significantly than that of the model control group. However, L-cysteine administration reduced the severity of injury in remote organs but not in the pancreas in rats with Na

In vivo multiphoton imaging of bile duct ligation

NASA Astrophysics Data System (ADS)

Liu, Yuan; Li, Feng-Chieh; Chen, Hsiao-Chin; Chang, Po-shou; Yang, Shu-Mei; Lee, Hsuan-Shu; Dong, Chen-Yuan

2008-02-01

Bile is the exocrine secretion of liver and synthesized by hepatocytes. It is drained into duodenum for the function of digestion or drained into gallbladder for of storage. Bile duct obstruction is a blockage in the tubes that carry bile to the gallbladder and small intestine. However, Bile duct ligation results in the changes of bile acids in serum, liver, urine, and feces1, 2. In this work, we demonstrate a novel technique to image this pathological condition by using a newly developed in vivo imaging system, which includes multiphoton microscopy and intravital hepatic imaging chamber. The images we acquired demonstrate the uptake, processing of 6-CFDA in hepatocytes and excretion of CF in the bile canaliculi. In addition to imaging, we can also measure kinetics of the green fluorescence intensity.

Dendritic Cells Regulate Treg-Th17 Axis in Obstructive Phase of Bile Duct Injury in Murine Biliary Atresia

PubMed Central

Tang, Shao-tao; Wang, Xin-xing; Cao, Guo-qing; Li, Shuai; Lei, Hai-yan; Zhang, Xi

2015-01-01

Several cell types are considered to be effector cells in bile duct injury in rhesus rotavirus (RRV)-induced experimental biliary atresia (BA). Here, we identified an increased T helper 17 (Th17) cell population in a BA mode. By depleting the Th17 cells, the BA symptoms (onset of jaundice, acholic stools and retarded growth) were attenuated and the survival rate was improved. Furthermore, we found that in mice with BA, the percentage of CD4+CD25highFoxp3+ T regulatory (Treg) cells decreased along with the increased percentage of Th17 cells. However, the absolute numbers of Treg and Th17 cells were both increased in liver of RRV-injected mice compared to saline-injected mice. The proportion of Th17 cells at 7 days post-infection was decreased if Treg cells isolated from normal adult mice, but not Treg cells from the livers of mice with BA, were intraperitoneally transferred on day 5 of life. In vitro experiments also showed that Treg cells from mice with BA had a diminished suppressive effect on Th17 cell generation. To determine the mechanisms, we investigated the production of cytokines in the liver. The level of IL-6, which has been shown to be abundantly secreted by activated dendritic cells (DCs), was remarkably elevated. Importantly, in a Treg/Th17 cell suppression assay, IL-6 was demonstrated to paralyze the Treg cells’ suppressive effect on Th17 cells and eventually the unrestrained increase of Th17 cells contributed to bile duct injury. In conclusion, the DC-regulated Treg-Th17 axis, probably in conjunction with other effector T cells, aggravates progressive inflammatory injury at the time of ductal obstruction. PMID:26325187

Endoscopic dacryocystorhinostomy with silicone, polypropylene, and T-tube stents; randomized controlled trial of efficacy and safety.

PubMed

Okuyucu, Semsettin; Gorur, Hatice; Oksuz, Huseyin; Akoglu, Ertap

2015-01-01

To compare the efficacy and safety of endoscopic dacryocystorhinostomy (En-DCR) with different stent materials for lacrimal sac intubation in primary nasolacrimal ductal obstructions. Randomized controlled study with three parallel groups. Level of evidence is 1b. A total of 91 patients (five bilateral) with primary nasolacrimal duct obstruction (NLDO) at a tertiary referral center scheduled for En-DCR were to allocated into three stent groups with a sealed envelope and were randomized into three treatments: silicone, Prolene (polypropylene), and otologic T-tube. Ophthalmology and otolaryngology clinics evaluated the patients preoperatively and postoperatively with endoscopes, lacrimal system syringing, and dacryocystography. The success of the stents was evaluated 12 months after surgery with symptom relief and ostial patency. Complications were also noted. The overall success rate of the En-DCR in the stent groups was 78.1% (75/96); specifically, 87.5% (28/32) with silicone, 84.4% (27/32) with Prolene, and 62.5% (20/32) with T-tube. The efficacy of the procedures with the T-tube was significantly lower than that of the Prolene and silicone (p = .031, χ(2) test). There were no significant differences between the silicone and Prolene (p = .718, χ(2) test). Prolene was found to be related with orbital complications. Spontaneous loss is a particular complication of otologic T-tube and highly portends to failure. The results of our study suggest that efficacy, defined as anatomic and functional success, is equally high for silicone and Prolene stents and lower for otologic T-tube in En-DCR.

Urgent endoscopic retrograde cholangiopancreatography is not superior to early ERCP in acute biliary pancreatitis with biliary obstruction without cholangitis.

PubMed

Lee, Hee Seung; Chung, Moon Jae; Park, Jeong Youp; Bang, Seungmin; Park, Seung Woo; Song, Si Young; Chung, Jae Bock

2018-01-01

Acute pancreatitis is a common diagnosis worldwide, with gallstone disease being the most prevalent cause (50%). The American College of Gastroenterology recommends urgent endoscopic retrograde cholangiopancreatography (ERCP) (within 24 h) for patients with biliary pancreatitis accompanied by cholangitis. Most international guidelines recommend that ERCP be performed within 72 h in patients with biliary pancreatitis and a bile duct obstruction without cholangitis, but the optimal timing for endoscopy is controversial. We investigated the optimal timing for ERCP in patients with biliary pancreatitis and a bile duct obstruction without cholangitis, and whether performing endoscopy within 24 h is superior to performing it after 24 h. We analyzed the clinical data of 505 patients with newly diagnosed acute pancreatitis, from January 1, 2005 to December 31, 2014. We divided the patients into two groups according to the timing of ERCP: < 24 h (urgent) and 24-72 h (early).Among the 505 patients, 73 were diagnosed with biliary pancreatitis and a bile duct obstruction without cholangitis. The mean age of the patients was 55 years (range: 26-90 years). Bile duct stones and biliary sludge were identified on endoscopy in 45 (61.6%) and 11 (15.0%) patients, respectively. The timing of ERCP within 72 h was not associated with ERCP-related complications (P = 0.113), and the total length of hospital stay was not different between urgent and early ERCP (5.9 vs. 5.7 days, P = 0.174). No significant differences were found in total length of hospitalization or procedural-related complications, in patients with biliary pancreatitis and a bile duct obstruction without cholangitis, according to the timing of ERCP (< 24 h vs. 24-72 h).

Coexistent Ampullary Squamous Cell Carcinoma with Adenocarcinoma of the Pancreatic Duct

PubMed Central

Pathak, Gayatri S.; Deshmukh, Sanjay D.; Yavalkar, Prasanna A.; Ashturkar, Amrut V.

2011-01-01

Primary squamous cell carcinoma (SCC) of ampulla has seldom been reported. However, metastatic SCC to ampulla of Vater is well known. We report a case of primary SCC of ampulla of Vater coexistent with well-differentiated adenocarcinoma of the distal pancreatic duct. A 50-year-old female presented with evidence of obstructive jaundice. Endoscopic retrograde cholangio-pancreatography revealed bulging papilla with ulcero-infiltrative growth at the ampulla of Vater. An initial endoscopic biopsy of the ampullary mass showed a well-differentiated SCC. The patient underwent Whipple's operation. Thorough sampling of the dilated portion of the pancreatic duct showed presence of well-differentiated adenocarcinoma of the distal pancreatic duct. Immunohistochemical study with synaptophysin and chromogranin was done with negative result, ruling out neuroendocrine differentiation. Also, a detailed clinical, endoscopic and radiological examination was carried out, that excluded the presence of primary SCC elsewhere. PMID:22064341

Biofilms and Physical Deposits on Nasolacrimal Silastic Stents Following Dacryocystorhinostomy: Is There a Difference Between Ocular and Nasal Segments?

PubMed

Ali, Mohammad Javed; Baig, Farhana; Lakshman, Mekala; Naik, Milind N

2015-01-01

The aims of this study were to examine the presence of biofilms and physical deposits on ocular and nasal segments of silastic nasolacrimal duct stents inserted after dacryocystorhinostomy and to document any differences. A prospective interventional study was performed on a series of patients undergoing dacryocystorhinostomy with Crawford stent insertion. All the patient samples were retrieved 4 weeks after an endoscopic dacryocystorhinostomy. None of the patients had any evidence of postoperative infection. The ocular and nasal segments were separated during retrieval. After removal, the stent segments were subjected to biofilm and physical deposit analysis using standard protocols of scanning electron microscopy. These stent segments were compared against sterile stents which acted as controls. A total of 11 stents were studied. Nine were consecutive patient samples and 2 were sterile stents. The ocular and nasal segments of all the stents demonstrated evidence of biofilm formation and physical deposits. However, the deposits and biofilms were thicker and extensive in the ocular segment, although more focal in nature. In contrast, the nasal segments showed thinner biofilms and sparser deposits but were more diffuse in nature. The presence of different-sized organisms within the exopolysaccharide matrix and in between the deposits suggests the existence of polymicrobial communities. This is the first study to report the differences between ocular and nasal segments of lacrimal stents. These differences could propel further studies on stent biomechanics and their interactions with ocular and nasal tissues, following a dacryocystorhinostomy.

The Chronic Obstructive Sialadenitis Symptoms Questionnaire to assess sialendoscopy-assisted surgery.

PubMed

Aubin-Pouliot, Annick; Delagnes, Elise A; Eisele, David W; Chang, Jolie L; Ryan, William R

2016-01-01

Introduce the Chronic Obstructive Sialadenitis Symptoms (COSS) questionnaire to quantify chronic sialadenitis symptoms and assess the impact of sialendoscopic-assisted salivary duct surgery (SASDS). Retrospective outcome symptoms questionnaire study. The COSS questionnaire assesses the severity of sialadenitis symptoms from 0 to 100. Patients who underwent SASDS from April 2006 to December 2013 completed the COSS questionnaire and the ShortForm8 Health Survey (SF-8) based on current symptoms, and reported whether they had complete, partial, or no symptomatic response to SASDS. Sixty-six of the 156 (43%) contacted patients completed the questionnaires who had had symptoms in 26 submandibular ducts and 53 parotid ducts. The mean COSS score was higher for parotid ducts (12.0; interquartile range [IQR] 1.0-20.0) than for submandibular ducts (7.6; IQR 0.5-15.0) but not significantly so (P = 0.20). Thirty-eight (60%) patients reported complete resolution of symptoms, with a mean COSS score of 4.5 (IQR 0-7). Twenty-one (33%) patients reported partial resolution, with a mean COSS score of 18.5 (IQR 11.3-22.8). Five (8%) patients reported no improvement, with a mean COSS score of 25.1 (IQR 15.2-35). Thirty-six (46%) ducts with sialoliths had a significantly lower mean COSS score (5.8; IQR 0-9.5) compared to those without sialoliths (14.2; IQR 4.5-21.5, P = 0.0004). There was no significant difference in SF-8 survey scores between these groups. The COSS questionnaire is a novel survey instrument to measure obstructive sialadenitis symptom severity that could be helpful in defining outcomes of SASDS. COSS scores under 10 correlate with complete resolution of symptoms, whereas scores between 10 and 25 correlate with partial resolution. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

The consequence of premature silicone stent loss after external dacryocystorhinostomy.

PubMed

Vicinanzo, Matthew G; McGwin, Gerald; Boyle, Michael; Long, John A

2008-07-01

To investigate the clinical affects of premature silicone stent loss after external dacryocystorhinostomy (DCR). Retrospective chart review. Two hundred thirty-three consecutive external dacryocystorhinostomies. Demographic information was recorded, including length to follow-up, age, gender, number of days until stent removal, and success of surgery. All patients who extruded their silicone stent prematurely were identified. All were primary DCRs (i.e., all reoperations were excluded). All patients had had documented nasolacrimal duct obstruction before surgery, with or without current or prior dacryocystitis. Failure of DCR surgery was accepted as symptomatic epiphora with notable nasolacrimal duct blockage and/or infection at long term follow-up. Of the 233 DCRs, 42 stents extruded or had to be removed before the planned 2-month period. The overall success rate of the surgery was 94.9%, with a 90.5% success for those who had early extrusion and 95.8% for those who did not (P = 0.24). Moreover, of the 4 people who had a failed surgery (of 42 early extrusions), none had a recurrent infection or pain, and only 1 opted to have a revision of the surgery. Patient age, gender, or timing of the extrusion was not found to affect surgical success significantly. Our experience and this study suggest that concerns over early stent extrusion or removal may not be wholly warranted. Moreover, our review of the literature shows no evidence-based recommendations that longer stent retention or reintubation after early extrusion results in a higher success rate. Although other surgeries (e.g., canalicular laceration, congenital epiphora) may benefit from intervention or reinsertion after early extrusion, we cannot extrapolate such a practice for the DCR.

Selective drainage for pancreatic, biliary, and duodenal obstruction secondary to chronic fibrosing pancreatitis.

PubMed Central

Sugerman, H J; Barnhart, G R; Newsome, H H

1986-01-01

Twenty-eight patients underwent surgery for intractable pain, duodenal or extrahepatic biliary obstruction secondary to chronic pancreatitis. Eleven had pancreatic duct obstruction alone, six biliary obstruction alone, seven combined pancreatic and biliary, two combined biliary and duodenal, one combined pancreatic and duodenal, and one simultaneous pancreatic, biliary, and duodenal obstruction. Pancreatitis was secondary to alcohol in all but one case. The following operations were performed: longitudinal pancreatojejunostomy (20), choledochoduodenostomy (8), choledochojejunostomy (7), cholecystojejunostomy (1), and gastrojejunostomy (4). Of the 20 patients with pancreatic duct drainage, pain relief was complete in 11 and partial in six. Initial incomplete relief of pain, or recurrence, stimulated further diagnostic procedures, leading to improvement or correction of the problem in five patients. A significant (p less than 0.01) fall in alkaline phosphatase (935 +/- 228 to 219 +/- 61 U/L) occurred following surgery. One patient was subsequently found to have pancreatic carcinoma. Two patients were lost to follow-up and four patients died (one perioperative and three late). In conclusion, the possibility of pancreatic, biliary, and duodenal obstruction must be considered in symptomatic patients with chronic pancreatitis. Surgery must be individualized. Drainage procedures, either alone or in combination, are associated with a low morbidity and improved clinical condition and may be preferable to resection in the surgical management of these patients. Images FIG. 1. FIG. 2. FIG. 4. PMID:3707234

A modal separation measurement technique for broadband noise propagating inside circular ducts

NASA Technical Reports Server (NTRS)

Kerschen, E. J.; Johnston, J. P.

1981-01-01

A measurement technique which separates broadband noise propagating inside circular ducts into the acoustic duct modes is developed. The technique is also applicable to discrete frequency noise. The acoustic modes are produced by weighted combinations of the instantaneous outputs of microphones spaced around the duct circumference. The technique is compared with the cross spectral density approach presently available and found to have certain advantages, and disadvantages. Considerable simplification of both the new technique and the cross spectral density approach occurs when no correlation exists between different circumferential mode orders. The properties leading to uncorrelated modes and experimental tests which verify this condition are discussed. The modal measurement technique is applied to the case of broadband noise generated by flow through a coaxial obstruction (nozzle or orifice) in a pipe. Different circumferential mode orders are shown to be uncorrelated for this type of noise source.

Octreotide as Palliative Therapy for Cancer-Related Bowel Obstruction That Cannot Be Removed by Surgery

ClinicalTrials.gov

2012-05-31

Colorectal Cancer; Constipation, Impaction, and Bowel Obstruction; Extrahepatic Bile Duct Cancer; Gastric Cancer; Gastrointestinal Stromal Tumor; Nausea and Vomiting; Ovarian Cancer; Pancreatic Cancer; Peritoneal Cavity Cancer; Small Intestine Cancer

Ducted turbine theory with right angled ducts

NASA Astrophysics Data System (ADS)

McLaren-Gow, S.; Jamieson, P.; Graham, J. M. R.

2014-06-01

This paper describes the use of an inviscid approach to model a ducted turbine - also known as a diffuser augmented turbine - and a comparison of results with a particular one-dimensional theory. The aim of the investigation was to gain a better understanding of the relationship between a real duct and the ideal diffuser, which is a concept that is developed in the theory. A range of right angled ducts, which have a rim for a 90° exit angle, were modelled. As a result, the performance of right angled ducts has been characterised in inviscid flow. It was concluded that right angled ducts cannot match the performance of their associated ideal diffuser and that the optimum rotor loading for these turbines varies with the duct dimensions.

[Acute cholangitis in interstenosis space accompanied by two-component unit of the main bile duct].

PubMed

Yurchenko, V V

2016-02-01

Palliative treatment of obstructive jaundice with the help of biliary endoprosthesis due to the possible complication of post-intervention in the form of insolvency stent deformation or dislocation. The study features in the postoperative period of the main bile duct endoprosthesis about their two-component unit, described the syndrome of the closed space of the bile ducts. On the basis of observation of 14 patients with the given anatomical feature of endoscopic, who were underwent stenting, was assessed frequency of the syndrome and possibilities of its prevention. Interstenosis space expansion of the main bile duct can be a reason for local cholangitis. For the prevention of cholangitis, it should be carried out a separate drainage of interstenosis space with the help of endoprosthesis or by proximal supra-stenotic extension of two or more stents.

Granular Cell Tumor of the Common Hepatic Duct as an Unusual Cause of Jaundice in a Hepatitis C Patient.

PubMed

Chopade, Tripti R; Smith, Colin L; Maley, Warren R; Siddiqui, Ali A; Sass, David A

2016-01-01

A 33-year-old woman with a history of intravenous cocaine abuse presented with fatigue, nausea, and jaundice. Serologic testing revealed a positive hepatitis C virus (HCV) antibody and HCV RNA. Ultrasound and magnetic resonance imaging/magnetic resonance cholangiopancreatography showed a partially obstructing lesion in the common hepatic duct, which was confirmed by endoscopic retrograde cholangiopancreatography. Surgical excision revealed a granular cell tumor of the common hepatic duct, with immunohistochemical staining of tumor cells positive for S-100.

External Versus Internal Pancreatic Duct Drainage for the Early Efficacy After Pancreaticoduodenectomy: A Retrospectively Comparative Study.

PubMed

Wang, Gang; Li, Le; Ma, Yuan; Qu, Feng-Zhi; Zhu, Hong; Lv, Jia-Chen; Jia, Yue-Hui; Wu, Lin-Feng; Sun, Bei

2016-08-01

To compare the early efficacy of external versus internal pancreatic duct drainage after pancreaticoduodenectomy (PD), providing clinical evidence for selecting the optimal approach to pancreatic duct drainage. The clinical data of 395 consecutive patients undergoing PD from 2006 to 2013 were analyzed retrospectively. All the patients were divided into external and internal drainage group. Intraoperative blood loss, surgery duration, postoperative hospitalization duration, mortality rate, PF, and other complications were compared between the two groups. The perioperative relative risk factors that might induce PF were analyzed. External drainage significantly reduced the incidences of post-PD PF, delayed gastric emptying, abdominal infection, bowel obstruction, overall complications, and shortened the healing time of PF (p < .05). The univariate analysis showed that the pancreatic duct drainage method, body mass index (BMI), preoperative serum bilirubin level, perioperative blood transfusion, pancreaticojejunostomy approach, pancreatic texture, pancreatic duct diameter, and primary disease differed markedly between the two groups (p < .05). A multivariate analysis revealed that BMI ≥ 25 kg/m(2), internal pancreatic duct drainage, pancreatic duct diameter <3 mm, soft pancreatic texture, and ampullary disease were independent risk factors for PF. External pancreatic duct drainage can effectively reduce the morbidity of PF and overall complications after PD.

Characteristics, Causes, and Evaluation of Helicopter Particulate Visual Obstruction

DTIC Science & Technology

2012-09-10

future full-scale testing. The thrust sources examined were a 1 in. diameter nozzle , a 4 in. diameter nozzle , and a 16 in. ducted fan. The sources...Hiller also evaluated inclining the thrust vector , and determined there was little reduction in dynamic pressure at the point of ground interaction...CHARACTERISTICS, CAUSES, AND EVALUATION OF HELICOPTER PARTICULATE VISUAL OBSTRUCTION THESIS

Modern management of obstructive salivary diseases

PubMed Central

Capaccio, P; Torretta, S; Ottaviani, F; Sambataro, G; Pignataro, L

2007-01-01

Summary Over the last fifteen years, increasing public demand for minimally-invasive surgery and recent technological advances have led to the development of a number of conservative options for the therapeutic management of obstructive salivary disorders such as calculi and duct stenosis. These include extracorporeal shock-wave lithotripsy, sialoendoscopy, laser intra-corporeal lithotripsy, interventional radiology, the video-assisted conservative surgical removal of parotid and sub-mandibular calculi and botulinum toxin therapy. Each of these techniques may be used as a single therapeutic modality or in combination with one or more of the above-mentioned options, usually in day case or one-day case under local or general anaesthesia. The multi-modal approach is completely successful in about 80% of patients and reduces the need for gland removal in 3%, thus justifying the combination of, albeit, time-consuming and relatively expensive techniques as part of the modern and functional management of salivary calculi. With regard to the management of salivary duct anomalies, such as strictures and kinkings, interventional radiology with fluoroscopically controlled balloon ductoplasty seems to be the most suitable technique despite the use of radiation. Operative sialoendoscopy alone is the best therapeutic option for all mobile intra-luminal causes of obstruction, such as microliths, mucous plugs or foreign bodies, or for the local treatment of inflammatory conditions such as recurrent chronic parotitis or autoimmune salivary disorders. Finally, in the case of failure of one of the above techniques and regardless of the cause of obstruction, botulinum toxin injection into the parenchyma of the salivary glands using colour Doppler ultrasonographic monitoring should be considered before deciding on surgical gland removal. PMID:17957846

Single-Operator Peroral Cholangioscopy for Extraction of Cystic Duct Stones in Postcholecystectomy Mirizzi Syndrome.

PubMed

Jones, Jason Deforest; Pawa, Rishi

2017-01-01

Mirizzi syndrome is an exceptionally rare diagnosis with an annual incidence of less than 1% in developed countries. In this disease process, stone burden in the cystic duct or gallbladder neck leads to common hepatic duct obstruction, either by mechanical compression or secondary inflammation. Mirizzi syndrome is classified into one of four types based on the presence and severity of cholecystobiliary fistulization. Treatment is primarily surgical in nature and largely dictated by the type of Mirizzi syndrome encountered. It is typically diagnosed in the preoperative or operative setting of cholecystectomy; however, there have been rare occurrences of postcholecystectomy diagnosis. Factors thought to predispose to postcholecystectomy disease include low insertion of the cystic duct and long remnant duct length. Few case reports exist describing this phenomenon and its management, which is made exceptionally difficult due to the presence of inflammation and surgical adhesion. We present the case of a young female with postcholecystectomy Mirizzi syndrome who underwent successful endoscopic management using peroral cholangioscopy and electrohydraulic lithotripsy. We also provide a brief overview of both Mirizzi syndrome and peroral cholangioscopy.

Bile duct injury: management options during and after gallbladder surgery.

PubMed

Vecchio, R; MacFadyen, B V; Ricardo, A E

1998-06-01

Proper management of iatrogenic bile duct injuries is mandatory to avoid immediate or late life threatening sequelae. Results of surgery depend mainly on the type of injury, the detection of the injury, and the timing of the surgery. Lesions detected during cholecystectomy should be repaired immediately, preferably with an end-to-side biliary anastomosis, a Roux-en-Y bilio-enteric anastomosis, or by the insertion of a T-tube. Bile duct injuries detected in the postoperative phase require a multidisciplinary approach and an algorithm for treatment of each type of lesion is proposed. In bile peritonitis with biliary obstruction and/or transection and in tight long strictures, which develop several months after cholecystectomy, a Roux-en-Y hepatico-jejunostomy is the most commonly performed operation. Other surgical techniques include a "mucosal graft" procedure and intrahepatic biliary enteric anastomoses, which may be required in difficult high-biliary lesions. Endoscopy and/or interventional radiology offer the best treatment options in bile duct leaks and in short ductal strictures that involve less than 50% of the bile duct lumen. In these injuries, surgical management should be performed only in the failure of nonsurgical methods. Because these lesions involve complicated biliary surgery, therapeutic endoscopy, and interventional radiology, treatment should be performed where there is expertise in all three areas. Copyright 1998 W.B. Saunders Company.

Amplatzer angled duct occluder for closure of patent ductus arteriosus larger than the aorta in an infant.

PubMed

Vijayalakshmi, I B; Chitra, N; Rajasri, R; Prabhudeva, A N

2005-01-01

Transcatheter closure of patent ductus arteriosus (PDA) by Amplatzer duct occluder is the treatment of choice. However, closure of very large ducts in infants with low weight is a challenge for the interventionalist because a large device may obstruct the aorta or left pulmonary artery. Difficulty is also encountered in advancing the device around the curve of the right ventricular outflow tract toward the pulmonary artery; this curve is tight, more or less at a right angle in infants, leading to kinking of the sheath, which increases fluoroscopic time. This is the first reported case of a very large PDA (8.7 mm), larger than the aorta (8.2 mm), successfully closed by an Amplatzer angled duct occluder in an infant weighing 5 kg.

Differentiation of benign and malignant ampullary obstruction by multi-row detector CT.

PubMed

Angthong, Wirana; Jiarakoop, Kran; Tangtiang, Kaan

2018-05-21

To determine useful CT parameters to differentiate ampullary carcinomas from benign ampullary obstruction. This study included 93 patients who underwent abdominal CT, 31 patients with ampullary carcinomas, and 62 patients with benign ampullary obstruction. Two radiologists independently evaluated CT parameters then reached consensus decisions. Statistically significant CT parameters were identified through univariate and multivariate analyses. In univariate analysis, the presence of ampullary mass, asymmetric, abrupt narrowing of distal common bile duct (CBD), dilated intrahepatic bile duct (IHD), dilated pancreatic duct (PD), peripancreatic lymphadenopathy, duodenal wall thickening, and delayed enhancement were more frequently in ampullary carcinomas observed (P < 0.05). Multivariate logistic regression analysis using significant CT parameters and clinical data from univariate analysis, and clinical symptom with jaundice (P = 0.005) was an independent predictor of ampullary carcinomas. For multivariate analysis using only significant CT parameters, abrupt narrowing of distal CBD was an independent predictor of ampullary carcinomas (P = 0.019). Among various CT criteria, abrupt narrowing of distal CBD and dilated IHD had highest sensitivity (77.4%) and highest accuracy (90.3%). The abrupt narrowing of distal CBD and dilated IHD is useful for differentiation of ampullary carcinomas from benign entity in patients without the presence of mass.

Endoscopic Modified Medial Maxillectomy for Resection of an Inverted Papilloma Originating from the Entire Circumference of the Maxillary Sinus

PubMed Central

Wada, Kota; Ishigaki, Takashi; Ida, Yutaro; Yamada, Yuki; Hosono, Sachiko; Edamatsu, Hideo

2015-01-01

For treatment of a sinonasal inverted papilloma (IP), it is essential to have a definite diagnosis, to identify its origin by computed tomography (CT) and magnetic resonance imaging (MRI), and to select the appropriate surgical approach based on the staging system proposed by Krouse. Recently, a new surgical approach named endoscopic modified medial maxillectomy (EMMM) was proposed. This approach can preserve the inferior turbinate and nasolacrimal duct. We successfully treated sinonasal IP with EMMM in a 71-year-old female patient. In this patient, the sinonasal IP originated from the entire circumference of the maxillary sinus. EMMM is not a difficult procedure and provides good visibility of the operative field. Lacrimation and empty nose syndrome do not occur postoperatively as the nasolacrimal duct and inferior turbinate are preserved. EMMM is considered to be a very favorable approach for treatment of sinonasal IP. PMID:26146581

Combined Endoscopic and Laparoscopic Management of Postcholecystectomy Mirizzi Syndrome from a Remnant Cystic Duct Stone: Case Report and Review of the Literature

PubMed Central

Amin, Arpit; Zhurov, Yuriy; Ibrahim, George; Maffei, Anthony; Giannone, Jonathan; Cerabona, Thomas; Kaul, Ashutosh

2016-01-01

Mirizzi syndrome has been defined in the literature as common bile duct obstruction resulting from calculi within Hartmann's pouch or cystic duct. We present a case of a 78-year-old female, who developed postcholecystectomy Mirizzi syndrome from a remnant cystic duct stone. Diagnosis of postcholecystectomy Mirizzi syndrome was made on endoscopic retrograde cholangiography (ERCP) performed postoperatively. The patient was treated with a novel strategy by combining advanced endoscopic and laparoscopic techniques in three stages as follows: Stage 1 (initial presentation): endoscopic sphincterotomy with common bile duct stent placement; Stage 2 (6 weeks after Stage 1): laparoscopic ultrasonography to locate the remnant cystic duct calculi followed by laparoscopic retrieval of the calculi and intracorporeal closure of cystic duct stump; Stage 3 (6 weeks after Stage 2): endoscopic removal of common bile duct stent along with performance of completion endoscopic retrograde cholangiogram. In addition, we have performed an extensive review of the various endoscopic and laparoscopic management techniques described in the literature for the treatment of postcholecystectomy syndrome occurring from retained cystic duct stones. PMID:27047698

Combined Endoscopic and Laparoscopic Management of Postcholecystectomy Mirizzi Syndrome from a Remnant Cystic Duct Stone: Case Report and Review of the Literature.

PubMed

Amin, Arpit; Zhurov, Yuriy; Ibrahim, George; Maffei, Anthony; Giannone, Jonathan; Cerabona, Thomas; Kaul, Ashutosh

2016-01-01

Mirizzi syndrome has been defined in the literature as common bile duct obstruction resulting from calculi within Hartmann's pouch or cystic duct. We present a case of a 78-year-old female, who developed postcholecystectomy Mirizzi syndrome from a remnant cystic duct stone. Diagnosis of postcholecystectomy Mirizzi syndrome was made on endoscopic retrograde cholangiography (ERCP) performed postoperatively. The patient was treated with a novel strategy by combining advanced endoscopic and laparoscopic techniques in three stages as follows: Stage 1 (initial presentation): endoscopic sphincterotomy with common bile duct stent placement; Stage 2 (6 weeks after Stage 1): laparoscopic ultrasonography to locate the remnant cystic duct calculi followed by laparoscopic retrieval of the calculi and intracorporeal closure of cystic duct stump; Stage 3 (6 weeks after Stage 2): endoscopic removal of common bile duct stent along with performance of completion endoscopic retrograde cholangiogram. In addition, we have performed an extensive review of the various endoscopic and laparoscopic management techniques described in the literature for the treatment of postcholecystectomy syndrome occurring from retained cystic duct stones.

Iodine-131 Therapy and Lacrimal Drainage System Toxicity: Nasal Localization Studies Using Whole Body Nuclear Scintigraphy and SPECT-CT.

PubMed

Ali, Mohammad Javed; Vyakaranam, Achyut Ram; Rao, Jyotsna Eleshwarapu; Prasad, Giri; Reddy, Palkonda Vijay Anand

The objective of this study was to evaluate the influence of dose on nasal localization of radioactive iodine-131 (I-131) following therapy for differentiated thyroid carcinomas. Retrospective evaluation of all patients who underwent post-therapy I-131 whole body scintigraphy and single photon emission computed tomography was performed. Patients were divided into 2 groups; group A were treated with 100 millicurie (mCi) and group B with ≥150 mCi. Databases were reviewed for demographics, diagnosis, and administered dosage of I-131. Whole body scintigraphy images were retrieved and nasal uptake was analyzed and classified as nil to trace, low, moderate, and high uptake and corresponding single photon emission CTs were analyzed for radioactive nasal activity. A total of 100 patients were studied, 50 in each of the groups. The M:F ratio was 1.1:1 (27:23) in group A and 1.5:1 (30:20) in group B. The mean age was 43.12 years and 54.6 years in groups A and B, respectively. Papillary carcinoma of the thyroid was the most common type accounting for 82% (41/50) of patients in group A and 62% (31/50) in group B. Imaging studies revealed nil to trace nasal activity in 80% (40/50) in group A as compared with 56% (28/50) in group B. None of the patients in group A showed high nasal uptake, whereas 4% (2/50) in group B demonstrated such high activity. Intranasal localization of radioactive I-131 was significant in patients receiving a dose of ≥150 mCi. Intranasal localization may partly explain toxicity to nasolacrimal duct and may be a risk factor for subsequent development of nasolacrimal duct obstructions.

Outcome of gallbladder preservation in surgical management of primary bile duct stones.

PubMed

Tian, Ming-Guo; Shi, Wei-Jin; Wen, Xin-Yuan; Yu, Hai-Wen; Huo, Jing-Shan; Zhou, Dong-Feng

2003-08-01

To evaluate the methods and outcome of gallbladder preservation in surgical treatment of primary bile duct stones. Thirty-five patients with primary bile duct stones and intact gallbladders received stone extraction by two operative approaches, 23 done through the intrahepatic duct stump (RBD-IDS, the RBD-IDS group) after partial hepatectomy and 12 through the hepatic parenchyma by retrograde puncture (RBD-RP, the RBD-RP group). The gallbladders were preserved and the common bile duct (CBD) incisions were primarily closed. The patients were examined postoperatively by direct cholangiography and followed up by ultrasonography once every six months. In the RBD-IDS group, residual bile duct stones were found in three patients, which were cleared by a combination of fibrocholedochoscopic extraction and lithotripsy through the drainage tracts. The tubes were removed on postoperative day 22 (range: 16-42 days). In the RBD-RP group, one patient developed hemobilia and was cured by conservative therapy. The tubes were removed on postoperative day 8 (range: 7-11 days). Postoperative cholangiography showed that all the gallbladders were well opacified, contractile and smooth. During 54 (range: 6-120 months) months of follow-up, six patients had mildly thickened cholecystic walls without related symptoms and further changes, two underwent laparotomies because of adhesive intestinal obstruction and gastric cancer respectively, three died of cardiopulmonary diseases. No stones were found in all the preserved gallbladders. The intact gallbladders preserved after surgical extraction of primary bile duct stones will not develop gallstones. Retrograde biliary drainage is an optimal approach for gallbladder preservation.

Amniotic Band Syndrome: A Review of 2 Cases.

PubMed

Madan, Siddharth; Chaudhuri, Zia

2018-04-03

Amniotic band syndrome is a rare congenital disorder caused by entrapment of fetal parts (usually a limb or digits) in fibrous amniotic bands while in utero that presents with complex multisystem anomalies. The authors report 2 children with amniotic band syndrome who presented to the ophthalmic unit of the authors' pediatric hospital. One of them presented with telecanthus, syndactyly, amputated toes, and unilateral epiphora diagnosed as congenital nasolacrimal duct obstruction. She was managed conservatively with lacrimal sac massage and provided with refractive correction while she simultaneously underwent multiple surgeries for correction of clubfoot and craniosynostosis. The second patient presented with cleft lip, cleft palate, multiple constriction bands in upper limbs and fingers with unilateral microphthalmos, microcornea, typical iris coloboma, and retinochoroidal coloboma, very similar to a case reported in literature. These 2 cases provide an overview of the clinical spectrum of ophthalmic manifestations along with their staged optimum rehabilitation.

Duct Joining System

DOEpatents

Proctor, John P.

2001-02-27

A duct joining system for providing an air-tight seal and mechanical connection for ducts and fittings is disclosed. The duct joining system includes a flexible gasket affixed to a male end of a duct or fitting. The flexible gasket is affixed at an angle relative to normal of the male end of the duct. The female end of the other duct includes a raised bead in which the flexible gasket is seated when the ducts are properly joined. The angled flexible gasket seated in the raised bead forms an air-tight seal as well as fastens or locks the male end to the female end. Alternatively, when a flexible duct is used, a band clamp with a raised bead is clamped over the female end of the flexible duct and over the male end of a fitting to provide an air tight seal and fastened connection.

Duct joining system

DOEpatents

Proctor, John P.; deKieffer, Robert C.

2001-01-01

A duct joining system for providing an air-tight seal and mechanical connection for ducts and fittings is disclosed. The duct joining system includes a flexible gasket affixed to a male end of a duct or fitting. The flexible gasket is affixed at an angle relative to normal of the male end of the duct. The female end of the other duct includes a raised bead in which the flexible gasket is seated when the ducts are properly joined. The angled flexible gasket seated in the raised bead forms an air-tight seal as well as fastens or locks the male end to the female end. Alternatively, when a flexible duct is used, a band clamp with a raised bead is clamped over the female end of the flexible duct and over the male end of a fitting to provide an air tight seal and fastened connection.

Lensing duct

DOEpatents

Beach, R.J.; Benett, W.J.

1994-04-26

A lensing duct to condense (intensify) light using a combination of front surface lensing and reflective waveguiding is described. The duct tapers down from a wide input side to a narrow output side, with the input side being lens-shaped and coated with an antireflective coating for more efficient transmission into the duct. The four side surfaces are uncoated, preventing light from escaping by total internal reflection as it travels along the duct (reflective waveguiding). The duct has various applications for intensifying light, such as in the coupling of diode array pump light to solid state lasing materials, and can be fabricated from inexpensive glass and plastic. 3 figures.

De-novo cholangiocarcinoma in native common bile duct remnant following OLT for primary sclerosing cholangitis.

PubMed

Landaverde, Carmen; Ng, Vivian; Sato, Alisa; Tabibian, James; Durazo, Francisco; Busuttil, Ronald

2009-01-01

Primary sclerosing cholangitis (PSC) is a chronic, progressive, inflammatory and obstructive disease of the intra- and extra-hepatic bile ducts of unknown etiology. Currently, orthotopic liver transplantation (OLT) is the only definitive treatment for PSC-related end-stage liver disease. However, PSC has been known to recur in the grafted liver. Roux-en-Y hepaticojejunostomy is more commonly performed than choledochocholedochostomy for PSC, although choledochocholedochostomy has been found to be safe and efficacious for PSC if the distal common bile duct is uninvolved at the time of OLT. Our case is unique in that it describes a patient who developed de-novo cholangiocarcinoma in the remnant portion of the native common bile duct six years after OLT with choledochocholedochostomy for PSC-associated end-stage liver disease without having PSC recurrence. In conclusion, our case report indicates that choledochocholedochostomy may not be desirable in PSC due to an increased risk of developing cholangiocarcinoma in the native common bile duct. This risk exists as well with a Roux-en-Y hepaticojejunostomy in the remaining intra-duodenal and intra-pancreatic biliary epithelium, although in theory to a lesser extent. Therefore, the risk of developing cholangiocarcinoma in the recipient common bile duct can only be completely eliminated by performing a Whipple procedure at the time of OLT.

Palliative percutaneous transhepatic drainage for inoperable obstructive jaundice.

PubMed Central

Baxter-Smith, D. C.; Temple, J. G.; Howarth, F.

1982-01-01

A technique of percutaneous transhepatic drainage under local anaesthesia is described for the relief of intractable pruritus in patients with obstructive jaundice due to inoperable carcinoma. After standard percutaneous transhepatic cholangiography a polyethylene catheter is introduced into one of the large dilated bile ducts and left in situ, thereby establishing external retrograde biliary drainage. The technique has been used successfully in 6 cases with reduction in serum bilirubin levels and relief of pruritus. PMID:6182832

Management of maxillary sinus inverted papilloma via endoscopic partial medial maxillectomy with an inferior turbinate reversing approach.

PubMed

Wang, Feng; Yang, Yang; Wang, Shenqing; Chen, Haihong; Wang, Dehui; Wang, Qinying

2017-12-01

The aim of this study is to evaluate the efficacy of endoscopic treatment for maxillary inverted papilloma (IP) through partial medial maxillectomy with an inferior turbinate reversing approach. A retrospective analysis of patients treated in our institution for maxillary sinus IP between July 2011 and August 2015 was performed. Demographics, operative technique, characteristics of tumors, complications, postoperative follow-up, and recurrence were evaluated. Twenty-two patients were enrolled in the study. All tumor attachments were identified intraoperatively. Adequate visualization was obtained following our approach. All inferior turbinate and nasolacrimal ducts were preserved. The median follow-up time was 41 months. One recurrence occurred at the follow-up time of 27 months. Postoperative hemorrhage and numbness at the ipsilateral frontal teeth were reported in two and one patients, respectively. Endoscopic surgery through partial medial maxillectomy using an inferior turbinate reversing approach provides full access to the maxillary sinus and preserves the inferior turbinate and nasolacrimal duct.

Pancreatic Calculus Causing Biliary Obstruction: Endoscopic Therapy for a Rare Initial Presentation of Chronic Pancreatitis.

PubMed

Shetty, Anurag J; Pai, C Ganesh; Shetty, Shiran; Balaraju, Girisha

2015-09-01

Biliary obstruction in chronic calcific pancreatitis (CCP) is often caused by inflammatory or fibrotic strictures of the bile duct, carcinoma of head of pancreas or less commonly by compression from pseudocysts. Pancreatic calculi causing ampullary obstruction and leading to obstructive jaundice is extremely rare. The medical records of all patients with CCP or biliary obstruction who underwent endoscopic retrograde cholangiopancreatography (ERCP) over 4 years between 2010-2014 at Kasturba Medical College, Manipal were analyzed. Five patients of CCP with impacted pancreatic calculi at the ampulla demonstrated during ERCP were identified. All 5 presented with biliary obstruction and were incidentally detected to have CCP when evaluated for the same; 3 patients had features of cholangitis. All the patients were managed successfully by endoscopic papillotomy and extraction of pancreatic calculi from the ampulla with resolution of biliary obstruction. Pancreatic calculus causing ampullary obstruction, though very rare, should be considered as a possibility in patients with CCP complicated by biliary obstruction. Endoscopic therapy is affective in the resolution of biliary obstruction in such patients.

Gastro-pancreaticojejunostomy for treatment of pancreatic ductal obstruction in a post-Whipple procedure patient.

PubMed

Rodrigues-Pinto, Eduardo; Grimm, Ian S; Baron, Todd H

2015-01-01

We report a case of a woman with a medical history of classic Whipple surgery who underwent endoscopic ultrasound (EUS)-guided pancreatic drainage due to smouldering acute pancreatitis secondary to an obstructing pancreatic ductal stone. A gastro-pancreaticojejunostomy anastomosis was created anterogradely, with dilation of both the anastomoses in the same procedure, with subsequent decompression of the pancreatic duct. Endoscopic retrograde pancreatography (ERP) is often impossible to perform in patients with post-Whipple procedure anatomy due to inaccessibility to the pancreaticojejunostomy anastomosis. EUS-guided pancreatic drainage may be offered in these patients in whom the pancreatic duct cannot be accessed at ERP. It has been used as a platform for access to and drainage of the pancreatic duct either by rendezvous or transmural drainage. However, only one of four patients achieve successful completion of the rendezvous procedure. There are limited data regarding safety and long-term outcome of this procedure, as well as scant guidelines on the optimal time for leaving stents in place. We believe definitive endoscopic therapy should be attempted, whenever possible, after relief of obstruction. In our case, we expect that stent occlusion is inevitable and that long-term drainage is possible due to drainage occurring between the stent and the stone.

S-1-Induced Lacrimal Drainage Obstruction and Its Association with Ingredients/Metabolites of S-1 in Tears and Plasma: A Prospective Multi-institutional Study.

PubMed

Kim, Namju; Kim, Jin Won; Baek, Je-Hyun; Kim, Jin-Soo; Choung, Ho-Kyung; Kim, Tae-Yong; Lee, Kyung-Hun; Bang, Yung-Jue; Khwarg, Sang In; Ahn, Sang-Hoon; Park, Do Joong; Kim, Hyung-Ho; Chung, Jae-Yong; Ahn, Soyeon; Lee, Keun-Wook

2018-01-01

This prospective study was conducted to determine the incidence of lacrimal drainage obstruction (LDO) during S-1 chemotherapy and evaluate the association between the development of LDO and the concentrations of ingredients/metabolites of S-1 in tears and plasma. A total of 145 patients with gastric cancer who received adjuvant S-1 therapy were enrolled. Ophthalmologic examinations were performed regularly during S-1 chemotherapy. Concentrations of tegafur, 5-chloro-2,4-dihydroxypyridine (CDHP), and 5-fluorouracil at steady-state trough level were measured in both tears and plasma. Fifty-three patients (37%) developed LDO. The median time to the onset of LDO was 10.9 weeks, and LDO developed most frequently in the nasolacrimal duct. Univariable analyses revealed that an older age (≥ 70 years), creatinine clearance rate (Ccr) < 80 mL/min, 5-fluorouracil concentration in plasma ≥ 22.3 ng/mL (median), CDHP concentration in plasma ≥ 42.0 ng/mL (median), and tegafur concentration in tears ≥ 479.2 ng/mL (median) were related to increased development of LDO. Multivariable analysis indicated that a high plasma 5-fluorouracil concentration was predictive of increased development of LDO (hazard ratio, 2.02; p=0.040), along with older age and decreased Ccr. Patients with LDO also developed S-1-related non-hematologic toxicity more frequently than those without LDO (p=0.016). LDO is a frequent adverse event during S-1 chemotherapy. An older age, decreased Ccr, and high plasma 5-fluorouracil concentration were found to be independent risk factors for LDO. The high incidence of LDO warrants regular ophthalmologic examination and early intervention in patients receiving S-1 therapy.

Bile Duct Exploration

MedlinePlus

... Patients & Visitors Health Library Institutes & Departments Home / Health Library / Diagnostics & Testing / Bile Duct Exploration Advertising Policy Bile Duct Exploration Common bile duct exploration is ...

14 CFR 29.1103 - Induction systems ducts and air duct systems.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Induction systems ducts and air duct systems. 29.1103 Section 29.1103 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Induction System § 29.1103 Induction systems ducts and air duct...

14 CFR 25.1103 - Induction system ducts and air duct systems.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Induction system ducts and air duct systems. 25.1103 Section 25.1103 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Induction System § 25.1103 Induction system ducts and air duct...

Hollow lensing duct

DOEpatents

Beach, Raymond J.; Honea, Eric C.; Bibeau, Camille; Mitchell, Scott; Lang, John; Maderas, Dennis; Speth, Joel; Payne, Stephen A.

2000-01-01

A hollow lensing duct to condense (intensify) light using a combination of focusing using a spherical or cylindrical lens followed by reflective waveguiding. The hollow duct tapers down from a wide input side to a narrow output side, with the input side consisting of a lens that may be coated with an antireflective coating for more efficient transmission into the duct. The inside surfaces of the hollow lens duct are appropriately coated to be reflective, preventing light from escaping by reflection as it travels along the duct (reflective waveguiding). The hollow duct has various applications for intensifying light, such as in the coupling of diode array pump light to solid state lasing materials.

Experimental Study of Poly-l-Lactic Acid Biodegradable Stents in Normal Canine Bile Ducts

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

Yamamoto, Kiyosei, E-mail: yamakiyo@zg7.so-net.ne.jp; Yoshioka, Tetsuya; Furuichi, Kinya

Purpose: This study was designed to clarify the advantages of biodegradable stents in terms of mucosal reaction and biodegradation after placement. We designed a biodegradable stent and assessed stent degradation and changes in the normal bile ducts of dogs. Methods: The biodegradable stent is a balloon-expandable Z stent consisting of poly-l-lactic acid (PLLA) with a diameter of 6 mm and a length of 15 mm. We assessed four groups of three beagle dogs each at 1, 3, 6, and 9 months of follow-up. After evaluating stent migration by radiography and stent and bile duct patency by cholangiography, the dogs weremore » sacrificed to remove the bile duct together with the stent. The bile duct lumen was examined macroscopically and histologically, and the stent degradation was examined macroscopically and by scanning electron microscopy (SEM). Results: Bile duct obstruction was absent and none of the stents migrated. Macroscopic evaluation showed moderate endothelial proliferation in the bile ducts at the implant sites at 3 and 6 months and a slight change at 9 months. Slight mononuclear cell infiltration was histologically identified at all time points and epithelial hyperplasia that was moderate at 3 months was reduced to slight at 6 and 9 months. Stent degradation was macroscopically evident in all animals at 9 months and was proven by SEM in two dogs at 6 months and in all of them at 9 months. Conclusions: Our results suggest that PLLA bioabsorbable stents seems to be useful for implantation in the biliary system with further investigation.« less

[A case of groove pancreatitis (segmental form) presented with obstructive jaundice associated with pancreatobiliary maljunction].

PubMed

Hiramatsu, Kiyoshi; Ito, Takaaki; Kaburagi, Daisuke; Arai, Riki; Maruyama, Hideki; Naganuma, Atsushi; Kato, Kenji

2008-09-01

A 52-year-old-man was admitted to our hospital for obstructive jaundice. Percutaneous transhepatic cholangio drainage (PTCD) and endscopic retrograde cholangiopancreatography (ERCP) were performed, and pointed out stenosis of lower common bile duct (CBD) and pancreatobiliary maljunction. Brushing cytology of this lesion was negative for malignancy. CT and MRI revealed chronic inflammatory change in groove lesion with no mass formation suggesting tumor. So we diagnosed groove pancreatitis (segmental form) associated with pancreatobiliary maljunction, and operation (resection of the bile duct and biliary reconstruction by Roux-en-Y) was done. Resected specimen was revealed stenosis of the bile duct formed by fibrous tissue with no malignancy compatible to groove pancreatitis pathologically. This is first reported case of groove pancreatits associated with pancreatobiliary maljunction.

Does pharmaconutrition with L-arginine and/or alpha-tocopherol improve the gut barrier in bile duct ligated rats?

PubMed

Tuncyurek, P; Sari, M; Firat, O; Mutaf, I; Gulter, C; Tunger, A; Yuce, G; Yilmaz, M; Makay, O; Dayangac, M; Ersin, S

2006-01-01

Nitric oxide supplementation and antioxidant therapy modulate gut barrier function, but the relationships between enhanced nitric oxide production, antioxidant administration, and biliary obstruction remain unclear. We evaluated the role of nitric oxide and alpha-tocopherol supplementation in bile duct ligated rats. Fifty male Wistar albino rats underwent sham operation (group I; control animals) or bile duct ligation (groups II, III, IV, and V). The ligation groups received the following regimens: standard pellet diet (group II), pellet diet plus intramuscularly administered alpha-tocopherol (group III), and L-arginine-enriched pellet diet without (group IV) or with (group V) alpha-tocopherol. Nitric oxide, malondialdehyde, and alpha-tocopherol concentrations were assessed at the end of 3 weeks. Liver and intestinal samples were scored histologically. Mesenteric lymph node and liver cultures were assessed for bacterial translocation. The liver malondialdehyde concentration was highest in group III. The nitric oxide content in the liver was higher in groups III and V, as were the blood alpha-tocopherol levels. Bacterial translocation was evident following bile duct ligation, but did not differ among the treatment groups. Intestinal histology revealed that group III had the lowest villus height, that group V had the least villus count, and that group II had the highest mucous cell count. The fibrosis scores were higher in groups IV and V. An obvious effect of alpha-tocopherol (with or without L-arginine) on the gut barrier could not be demonstrated. Moreover, the L-arginine-enriched diet promoted fibrosis in the liver. Thus, while biliary duct obstruction triggers bacterial translocation, nitric oxide and/or alpha-tocopherol supplementation did not seem to improve the gut barrier in our model. Copyright 2006 S. Karger AG, Basel.

Mitomycin-C in dacryocystorhinostomy: From experimentation to implementation and the road ahead: A review.

PubMed

Nair, Akshay Gopinathan; Ali, Mohammad Javed

2015-04-01

Dacryocystorhinostomy (DCR) is the procedure of choice in patients with epiphora due to primary acquired nasolacrimal duct obstruction. The evolution of surgical tools, fiber-optic endoscopes, effective anesthesia techniques, and the adjunct use of antimetabolites intraoperatively; namely mitomycin-C (MMC) have significantly contributed to the advancement of DCR surgery. MMC is a systemic chemotherapeutic agent derived from Streptomyces caespitosus that inhibits the synthesis of DNA, cellular RNA, and protein by inhibiting the synthesis of collagen by fibroblasts. Even the cellular changes in the human nasal mucosal fibroblasts induced by MMC at an ultrastructural level have been documented. There, however, seems to be a lack of consensus regarding MMC: The dosage, the route of delivery/application, the time of exposure and subsequently what role each of these variables plays in the final outcome of the surgery. In this review, an attempt is made to objectively examine all the evidence regarding the role of MMC in DCR. MMC appears to improve the success rate of DCR.

Mitomycin-C in dacryocystorhinostomy: From experimentation to implementation and the road ahead: A review

PubMed Central

Nair, Akshay Gopinathan; Ali, Mohammad Javed

2015-01-01

Dacryocystorhinostomy (DCR) is the procedure of choice in patients with epiphora due to primary acquired nasolacrimal duct obstruction. The evolution of surgical tools, fiber-optic endoscopes, effective anesthesia techniques, and the adjunct use of antimetabolites intraoperatively; namely mitomycin-C (MMC) have significantly contributed to the advancement of DCR surgery. MMC is a systemic chemotherapeutic agent derived from Streptomyces caespitosus that inhibits the synthesis of DNA, cellular RNA, and protein by inhibiting the synthesis of collagen by fibroblasts. Even the cellular changes in the human nasal mucosal fibroblasts induced by MMC at an ultrastructural level have been documented. There, however, seems to be a lack of consensus regarding MMC: The dosage, the route of delivery/application, the time of exposure and subsequently what role each of these variables plays in the final outcome of the surgery. In this review, an attempt is made to objectively examine all the evidence regarding the role of MMC in DCR. MMC appears to improve the success rate of DCR. PMID:26044474

[Rare bile duct anatomy variant - Right bile duct intraparenchymal junction into the left bile duct].

PubMed

Gál, Adrián Róbert; Kalmár-Nagy, Károly; Fincsur, András; Horváth, Örs Péter; Vereczkei, András

2018-03-01

The authors present a case of a 67-year-old male patient, who previously had been diagnosed with a malignant liver tumor localized in segment II. He underwent bisegmentectomy (II and III) and partial IV segmentectomy. After the primary surgery jaundice developed, the level of bilirubin increased and after several imaging modalities reoperation was indicated. During the surgery a rare bile duct anatomy variant was found. The right hepatic duct joined the left duct in the parenchyma of the left lobe, and was ligated at the resection. As the liver hilum was not explored, the absence of the right duct was not discovered. Reconstruction of the biliary system was accomplished by a Roux-en-Y loop.

Mammary Duct Ectasia

MedlinePlus

... tenderness or inflammation of the clogged duct (periductal mastitis). Mammary duct ectasia most often occurs in women ... that's turned inward (inverted) A bacterial infection called mastitis also may develop in the affected milk duct, ...

[Portal thrombosis, common bile duct varices and cholestasis].

PubMed

Agüera Arroyo, B; Pérez Durán, M A; Montero Alvarez, J L; Navarro Jarabo, J M; Calero Ayala, B; Miño Fugarolas, G

1996-03-01

A case of cholestasis in a young patient with portal cavernomatosis is reported. This clinical picture is very infrequent and appears as a consequence of extrinsic compression on the common bile duct due to which the derivative venous collaterals. There does not appear to be any relationship between the intensity of the morphologic alteration of the biliary tract and the level of portal hypertension and the degree of extrahepatic obstruction. Diagnosis was fundamentally achieved by arteriography and retrograde cholangiography with differential diagnosis with the previously mentioned diseases being required. Chronic cholestasis advises derivative surgery in which difficulties may be found due to the presence of thick collaterals in the hepatic pedicle as occurred in this patient.

Duct closure

DOEpatents

Vowell, Kennison L.

1987-01-01

A closure for an inclined duct having an open upper end and defining downwardly extending passageway. The closure includes a cap for sealing engagement with the open upper end of the duct. Associated with the cap are an array of vertically aligned plug members, each of which has a cross-sectional area substantially conforming to the cross-sectional area of the passageway at least adjacent the upper end of the passageway. The plug members are interconnected in a manner to provide for free movement only in the plane in which the duct is inclined. The uppermost plug member is attached to the cap means and the cap means is in turn connected to a hoist means which is located directly over the open end of the duct.

Giant Meckel’s diverticulum: An exceptional cause of intestinal obstruction

PubMed Central

Akbulut, Sami; Yagmur, Yusuf

2014-01-01

Meckel’s diverticulum (MD) results from incomplete involution of the proximal portion of the vitelline (also known as the omphalomesenteric) duct during weeks 5-7 of foetal development. Although MD is the most commonly diagnosed congenital gastrointestinal anomaly, it is estimated to affect only 2% of the population worldwide. Most cases are asymptomatic, and diagnosis is often made following investigation of unexplained gastrointestinal bleeding, perforation, inflammation or obstruction that prompt clinic presentation. While MD range in size from 1-10 cm, cases of giant MD (≥ 5 cm) are relatively rare and associated with more severe forms of the complications, especially for obstruction. Herein, we report a case of giant MD with secondary small bowel obstruction in an adult male that was successfully managed by surgical resection and anastomosis created with endoscopic stapler device (80 mm, endo-GIA stapler). Patient was discharged on post-operative day 6 without any complications. Histopathologic examination indicated Meckel’s diverticulitis without gastric or pancreatic metaplasia. PMID:24672650

Hedgehog-mediated mesenchymal-epithelial interactions modulate hepatic response to bile duct ligation.

PubMed

Omenetti, Alessia; Yang, Liu; Li, Yin-Xiong; McCall, Shannon J; Jung, Youngmi; Sicklick, Jason K; Huang, Jiawen; Choi, Steve; Suzuki, Ayako; Diehl, Anna Mae

2007-05-01

In bile duct-ligated (BDL) rodents, as in humans with chronic cholangiopathies, biliary obstruction triggers proliferation of bile ductular cells that are surrounded by fibrosis produced by adjacent myofibroblastic cells in the hepatic mesenchyme. The proximity of the myofibroblasts and cholangiocytes suggests that mesenchymal-epithelial crosstalk promotes the fibroproliferative response to cholestatic liver injury. Studying BDL mice, we found that bile duct obstruction induces activity of the Hedgehog (Hh) pathway, a system that regulates the viability and differentiation of various progenitors during embryogenesis. After BDL, many bile ductular cells and fibroblastic-appearing cells in the portal stroma express Hh ligands, receptor and/or target genes. Transwell cocultures of an immature cholangiocyte line that expresses the Hh receptor, Patched (Ptc), with liver myofibroblastic cells demonstrated that both cell types produced Hh ligands that enhanced each other's viability and proliferation. Further support for the concept that Hh signaling modulates the response to BDL was generated by studying PtcLacZ mice, which have an impaired ability to constrain Hh signaling due to a heterozygous deficiency of Ptc. After BDL, PtcLacZ mice upregulated fibrosis gene expression earlier than wild-type controls and manifested an unusually intense ductular reaction, more expanded fibrotic portal areas, and a greater number of lobular necrotic foci. Our findings reveal that adult livers resurrect developmental signaling systems, such as the Hh pathway, to guide remodeling of the biliary epithelia and stroma after cholestatic injury.

[Intraoperative ultrasonography, dissection with ultra-shears and trans-cystic choledochoscopy during laparoscopic approach in obstructive lithiasis icterus case].

PubMed

Alecu, L; Corodeanu, G; Costan, I; Lungu, C; Staicu, A

2001-01-01

The authors present the case of a 48 years old male with lithiasis obstructive icterus who was operated by laparoscopic transcystic approach with choledochoscopy. This minimally invasive technique was very spectacular trough the using of laparoscopic ultrasonography, dissection with Ultra-Shears device and transcystic choledochoscopy. Careful watching of abdominal laparoscopic view and transcystic choledochoscopic view is the particularity of laparoscopic transcystic management of choledocholithiasis. This metod don't let us to explore the biliary tract before the junction between common bile duct and cystic duct.

Advanced Duct Sealing Testing

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

Sherman, Max H.; Walker, Iain S.

Duct leakage has been identified as a major source of energy loss in residential buildings. Most duct leakage occurs at the connections to registers, plenums or branches in the duct system. At each of these connections a method of sealing the duct system is required. Typical sealing methods include tapes or mastics applied around the joints in the system. Field examinations of duct systems have typically shown that these seals tend to fail over extended periods of time. The Lawrence Berkeley National Laboratory has been testing sealant durability for several years. Typical duct tape (i.e. fabric backed tapes with naturalmore » rubber adhesives) was found to fail more rapidly than all other duct sealants. This report summarizes the results of duct sealant durability testing of five UL 181B-FX listed duct tapes (three cloth tapes, a foil tape and an Oriented Polypropylene (OPP) tape). One of the cloth tapes was specifically developed in collaboration with a tape manufacturer to perform better in our durability testing. The first test involved the aging of common ''core-to-collar joints'' of flexible duct to sheet metal collars, and sheet metal ''collar-to-plenum joints'' pressurized with 200 F (93 C) air. The second test consisted of baking duct tape specimens in a constant 212 F (100 C) oven following the UL 181B-FX ''Temperature Test'' requirements. Additional tests were also performed on only two tapes using sheet metal collar-to-plenum joints. Since an unsealed flexible duct joint can have a variable leakage depending on the positioning of the flexible duct core, the durability of the flexible duct joints could not be based on the 10% of unsealed leakage criteria. Nevertheless, the leakage of the sealed specimens prior to testing could be considered as a basis for a failure criteria. Visual inspection was also documented throughout the tests. The flexible duct core-to-collar joints were inspected monthly, while the sheet metal collar-to-plenum joints were

Clinical features and outcomes of patients with hepatocellular carcinoma complicated with bile duct invasion.

PubMed

An, Jihyun; Lee, Kwang Sun; Kim, Kang Mo; Park, Do Hyun; Lee, Sang Soo; Lee, Danbi; Shim, Ju Hyun; Lim, Young-Suk; Lee, Han Chu; Chung, Young-Hwa; Lee, Yung Sang

2017-06-01

Little is known about the treatment or outcomes of hepatocellular carcinoma (HCC) complicated with bile duct invasion. A total of 247 consecutive HCC patients with bile duct invasion at initial diagnosis were retrospectively included. The majority of patients had Barcelona Clinic Liver Cancer (BCLC) stage C HCC (66.8%). Portal vein tumor thrombosis was present in 166 (67.2%) patients. Median survival was 4.1 months. Various modalities of treatment were initially employed including surgical resection (10.9%), repeated transarterial chemoembolization (TACE) (42.5%), and conservative management (42.9%). Among the patients with obstructive jaundice (n=88), successful biliary drainage was associated with better overall survival rate. Among the patients with BCLC stage C, overall survival differed depending on the initial treatment for HCC; surgical resection, TACE, systemic chemotherapy, and conservative management showed overall survival rates of 11.5, 6.0 ,2.4, and 1.6 months, respectively. After adjusting for confounders, surgical resection and repeated TACE were significant prognostic factors for HCC patients with bile duct invasion (hazard ratios 0.47 and 0.39, Ps <0.001, respectively). The survival of HCC patients with bile duct invasion at initial diagnosis is generally poor. However, aggressive treatments for HCC such as resection or biliary drainage may be beneficial therapeutic options for patients with preserved liver function.

Clinical features and outcomes of patients with hepatocellular carcinoma complicated with bile duct invasion

PubMed Central

An, Jihyun; Lee, Kwang Sun; Park, Do Hyun; Lee, Sang Soo; Lee, Danbi; Shim, Ju Hyun; Lim, Young-Suk; Lee, Han Chu; Chung, Young-Hwa; Lee, Yung Sang

2017-01-01

Background/Aims Little is known about the treatment or outcomes of hepatocellular carcinoma (HCC) complicated with bile duct invasion. Methods A total of 247 consecutive HCC patients with bile duct invasion at initial diagnosis were retrospectively included. Results The majority of patients had Barcelona Clinic Liver Cancer (BCLC) stage C HCC (66.8%). Portal vein tumor thrombosis was present in 166 (67.2%) patients. Median survival was 4.1 months. Various modalities of treatment were initially employed including surgical resection (10.9%), repeated transarterial chemoembolization (TACE) (42.5%), and conservative management (42.9%). Among the patients with obstructive jaundice (n=88), successful biliary drainage was associated with better overall survival rate. Among the patients with BCLC stage C, overall survival differed depending on the initial treatment for HCC; surgical resection, TACE, systemic chemotherapy, and conservative management showed overall survival rates of 11.5, 6.0 ,2.4, and 1.6 months, respectively. After adjusting for confounders, surgical resection and repeated TACE were significant prognostic factors for HCC patients with bile duct invasion (hazard ratios 0.47 and 0.39, Ps <0.001, respectively). Conclusions The survival of HCC patients with bile duct invasion at initial diagnosis is generally poor. However, aggressive treatments for HCC such as resection or biliary drainage may be beneficial therapeutic options for patients with preserved liver function. PMID:28506055

Scissors Duct

NASA Image and Video Library

2007-06-26

Stennis Space Center engineers are preparing to conduct water tests on an updated version of the scissors duct component of the J-2X engine. Measuring about 2 feet long and about 8 inches in diameter, the duct on the J-2X predecessor, the J-2, connected its fuel turbo pumps to the flight vehicle's upper stage run tanks. According to NASA's J-2X project manager at SSC, Gary Benton, the water tests should establish the limits of the duct's ability to withstand vibration.

User's Manual for DuctE3D: A Program for 3D Euler Unsteady Aerodynamic and Aeroelastic Analysis of Ducted Fans

NASA Technical Reports Server (NTRS)

Srivastava, R.; Reddy, T. S. R.

1997-01-01

The program DuctE3D is used for steady or unsteady aerodynamic and aeroelastic analysis of ducted fans. This guide describes the input data required and the output files generated, in using DuctE3D. The analysis solves three dimensional unsteady, compressible Euler equations to obtain the aerodynamic forces. A normal mode structural analysis is used to obtain the aeroelastic equations, which are solved using either the time domain or the frequency domain solution method. Sample input and output files are included in this guide for steady aerodynamic analysis and aeroelastic analysis of an isolated fan row.

Developing flow in S-shaped ducts. 2: Circular cross-section duct

NASA Technical Reports Server (NTRS)

Taylor, A. M. K. P.; Whitelaw, J. H.; Yianneskis, M.

1984-01-01

Laser-Doppler velocimetry measured the laminar and turbulent streamwise flow in a S-duct. The wall pressure distribution and one component of cross-stream velocity were also obtained for the turbulent flow case. Boundary layers near the duct inlet were about 25 percent of the hydraulic diameter in the laminar flow and varied around the periphery of the pipe between 10 percent and 20 percent in turbulent flow. Pressure-driven secondary flows develop in the first half of the S-duct and are attenuated and reversed in the second half. For both Reynolds numbers there is a region near the outer wall of the second half of the duct where the sign of the radial vorticity results in an enforcement of the secondary flow which was established in the first half of the S-duct. The core flow migrates, for both Reynolds numbers, to the outside wall of the first half and lies towards the inside wall of the second half of the S-duct at the outlet. The thinner inlet boundary layers in the turbulent flow give rise to weaker secondary motion.

Comparison of pitot traverses taken at varying distances downstream of obstructions.

PubMed

Guffey, S E; Booth, D W

1999-01-01

This study determined the deviations between pitot traverses taken under "ideal" conditions--at least seven duct diameter's lengths (i.e., distance = 7D) from obstructions, elbows, junction fittings, and other disturbances to flows--with those taken downstream from commonplace disturbances. Two perpendicular 10-point, log-linear velocity pressure traverses were taken at various distances downstream of tested upstream conditions. Upstream conditions included a plain duct opening, a junction fitting, a single 90 degrees elbow, and two elbows rotated 90 degrees from each other into two orthogonal planes. Airflows determined from those values were compared with the values measured more than 40D downstream of the same obstructions under ideal conditions. The ideal measurements were taken on three traverse diameters in the same plane separated by 120 degrees in honed drawn-over-mandrel tubing. In all cases the pitot tubes were held in place by devices that effectively eliminated alignment errors and insertion depth errors. Duct velocities ranged from 1500 to 4500 ft/min. Results were surprisingly good if one employed two perpendicular traverses. When the averages of two perpendicular traverses was taken, deviations from ideal value were 6% or less even for traverses taken as close as 2D distance from the upstream disturbances. At 3D distance, deviations seldom exceeded 5%. With single diameter traverses, errors seldom exceeded 5% at 6D or more downstream from the disturbance. Interestingly, percentage deviations were about the same at high and low velocities. This study demonstrated that two perpendicular pitot traverses can be taken as close as 3D from these disturbances with acceptable (< or = 5%) deviations from measurements taken under ideal conditions.

Lightweight Valve Closes Duct Quickly

NASA Technical Reports Server (NTRS)

Fournier, Walter L.; Burgy, N. Frank

1991-01-01

Expanding balloon serves as lightweight emergency valve to close wide duct. Uninflated balloon stored in housing of duct. Pad resting on burst diaphragm protects balloon from hot gases in duct. Once control system triggers valve, balloon inflates rapidly to block duct. Weighs much less than does conventional butterfly, hot-gas, or poppet valve capable of closing duct of equal diameter.

[Recurrent subareolar non puerperal abscess of breast with fistules of lactiferous ducts (Zuskas disease)].

PubMed

Móricová, P; Žúbor, P; Kapustová, I; Švecová, I; Danko, J

2013-09-01

Zuskas disease (ZD) is an illness also known as the recurrent subareolar non-puerperal abscess of breast with fistulas of lactiferous ducts or as a periductal mastitis. ZD is rare, but painful chronic disease of breast characterized by local inflammation and evacuation of viscous content from abscess around the nipple. We present a rare form of the non-puerperal mastitis in patients with recurrence of this disease and with the description of management and treatment. The treatment of ZD is often inadequate and it leads to the recurrence of ZD and retraction of the nipple. Definitive treatment of ZD is surgical excision of the fistulation, removing of whole retroareolar fibroglandular tissue, abscess cavity and ductal tissue inside the nipple, including the obstructed ducts. The ratio of patients cured by this method is high, as well as their satisfaction with the final cosmetic effect of the nipple and breast.

Laparoscopic completion cholecystectomy and common bile duct exploration for retained gallbladder after single-incision cholecystectomy.

PubMed

Kroh, Matthew; Chalikonda, Sricharan; Chand, Bipan; Walsh, R Matthew

2013-01-01

Recent enthusiasm in the surgical community for less invasive surgical approaches has resulted in widespread application of single-incision techniques. This has been most commonly applied in laparoscopic cholecystectomy in general surgery. Cosmesis appears to be improved, but other advantages remain to be seen. Feasibility has been demonstrated, but there is little description in the current literature regarding complications. We report the case of a patient who previously underwent single-incision laparoscopic cholecystectomy for symptomatic gallstone disease. After a brief symptom-free interval, she developed acute pancreatitis. At evaluation, imaging results of ultrasonography and magnetic resonance cholangiopancreatography demonstrated a retained gallbladder with cholelithiasis. The patient was subsequently referred to our hospital, where she underwent further evaluation and surgical intervention. Our patient underwent 4-port laparoscopic remnant cholecystectomy with transcystic common bile duct exploration. Operative exploration demonstrated a large remnant gallbladder and a partially obstructed cystic duct with many stones. Transcystic exploration with balloon extraction resulted in duct clearance. The procedure took 75 minutes, with minimal blood loss. The patient's postoperative course was uneventful. Final pathology results demonstrated a remnant gallbladder with cholelithiasis and cholecystitis. This report is the first in the literature to describe successful laparoscopic remnant cholecystectomy and transcystic common bile duct exploration after previous single-port cholecystectomy. Although inadvertent partial cholecystectomy is not unique to this technique, single-port laparoscopic procedures may result in different and significant complications.

Effects of selective bile duct ligation on liver parenchyma in young animals: histologic and molecular evaluations.

PubMed

Tannuri, Ana Cristina A; Coelho, Maria Cecília M; de Oliveira Gonçalves, Josiane; Santos, Maria Mercês; Ferraz da Silva, Luiz Fernando; Bendit, Israel; Tannuri, Uenis

2012-03-01

The mechanisms of increased collagen production and liver parenchyma fibrosis are poorly understood. These phenomena are observed mainly in children with biliary obstruction (BO), and in a great number of patients, the evolution to biliary cirrhosis and hepatic failure leads to the need for liver transplantation before adolescence. However, pediatric liver transplantation presents with biliary complications in 20% to 30% of cases in the postoperative period. Intra- or extrahepatic stenosis of bile ducts is frequent and may lead to secondary biliary cirrhosis and the need for retransplantation. It is unknown whether biliary stenosis involving isolated segments or lobes may affect the adjacent nonobstructed lobes by paracrine or endocrine means, leading to fibrosis in this parenchyma. Therefore, the present study aimed to create an experimental model of selective biliary duct ligation in young animals with a subsequent evaluation of the histologic and molecular alterations in liver parenchyma of the obstructed and nonobstructed lobes. After a pilot study to standardize the surgical procedures, weaning rats underwent ligation of the bile ducts of the median, left lateral, and caudate liver lobes. The bile duct of the right lateral lobe was kept intact. To avoid intrahepatic biliary duct collaterals neoformation, the parenchymal connection between the right lateral and median lobes was clamped. The animals were divided into groups according to the time of death: 1, 2, 3, 4, and 8 weeks after surgical procedure. After death, the median and left lateral lobes (with BO) and the right lateral lobe (without BO [NBO]) were harvested separately. A group of 8 healthy nonoperated on animals served as controls. Liver tissues were subjected to histologic evaluation and quantification of the ductular proliferation and of the portal fibrosis. The expressions of smooth muscle α-actin (α-SMA), desmin, and transforming growth factor β1 genes were studied by molecular analyses

Deleterious effect of oltipraz on extrahepatic cholestasis in bile duct-ligated mice

PubMed Central

Weerachayaphorn, Jittima; Luo, Yuhuan; Mennone, Albert; Soroka, Carol J.; Harry, Kathy; Boyer, James L.

2014-01-01

Background & Aims Oltipraz (4-methyl-5(pyrazinyl-2)-1-2-dithiole-3-thione), a promising cancer preventive agent, has an anti-oxidative activity and ability to enhance glutathione biosynthesis, phase II detoxification enzymes and multidrug resistance-associated protein-mediated efflux transporters. Oltipraz can protect against hepatotoxicity caused by carbon tetrachloride, acetaminophen and alpha-naphthylisothiocyanate. Whether oltipraz has hepato-protective effects on obstructive cholestasis is unknown. Methods We administered oltipraz to mice for 5 days prior to bile duct ligation (BDL) for 3 days. Liver histology, liver function markers, bile flow rates and hepatic expression of profibrogenic genes were evaluated. Results Mice pretreated with oltipraz prior to BDL demonstrated higher levels of serum aminotransferases and more severe liver damage than in control mice. Higher bile flow and glutathione secretion rates were observed in unoperated mice treated with oltipraz than in control mice, suggesting that liver necrosis in oltipraz-treated BDL mice may be related partially to increased bile-acid independent flow and biliary pressure. Oltipraz treatment in BDL mice enhanced -smooth muscle actin expression, consistent with activation of hepatic stellate cells and portal fibroblasts. Matrix metalloproteinases (MMP) 9 and 13 and tissue inhibitors of metalloproteinases (TIMP) 1 and 2 levels were increased in the oltipraz -treated BDL group, suggesting that the secondary phase of liver injury induced by oltipraz might be due to excessive MMP and TIMP secretions which induce remodeling of the extracellular matrix. Conclusions Oltipraz treatment exacerbates the severity of liver injury following BDL and should be avoided as therapy for extrahepatic cholestatic disorders due to bile duct obstruction. PMID:23978715

Closure of the patent ductus arteriosus with the Amplatzer Duct Occluder II: a clinical experience.

PubMed

Karagöz, Tevfik; Akin, Alper; Ertuğrul, Ilker; Aykan, Hayrettin Hakan; Alehan, Dursun; Ozer, Sema; Ozkutlu, Süheyla

2012-12-01

The aim of our study was to share our clinical experience on cases with patent ductus arteriosus treated with the Amplatzer Duct Occluder II. Between 2008 and 2012, 26 of 31 patients with patent ductus arteriosus underwent successful transcatheter closure of patent ductus arteriosus using the Amplatzer Duct Occluder II. Mean age was 3.3 years and mean weight was 15.7 kilograms. The presence of a residual shunt, left pulmonary artery or aortic obstruction was explored by administering contrast material during the procedure. The patients were discharged 24 hours after the procedure. The procedure was successful in 26 of 31 patients and failed in five patients. According to the Krichenko classification, 26 patients had type A, one patient had type B and 4 patients had type C ductus. The mean narrowest ductus diameter was 3.2 mm and the mean ductus length was 6.7 mm. Complete angiographic occlusion occurred immediately after the procedure in 22 out of 26 patients in whom the ductus was closed successfully with the Amplatzer Duct Occluder II. Complete occlusion was achieved in the remaining patients with residual shunt one month after the procedure. The procedure was preceded by closure with an Amplatzer Duct Occluder I in two patients and an Amplatzer Vascular Plug I in one patient. Amplatzer Duct Occluder II is highly effective in transcatheter closure of patent ductus arteriosus. We think that an alternative closure device and alternative techniques can be attempted in patients with type C ductus. The success rate could increase with accumulating experience.

Effect of honey on bacterial translocation and intestinal morphology in obstructive jaundice

PubMed Central

Gencay, Cem; Kilicoglu, Sibel Serin; Kismet, Kemal; Kilicoglu, Bulent; Erel, Serap; Muratoglu, Sabahattin; Sunay, Asli Elif; Erdemli, Esra; Akkus, Mehmet Ali

2008-01-01

AIM: To evaluate the effects of honey on bacterial translocation and intestinal villus histopathology in experimental obstructive jaundice. METHODS: Thirty Wistar-Albino rats were randomly divided into three groups each including 10 animals: group I, sham-operated; group II, ligation and section of the common bile duct (BDL); group III, bile duct ligation followed by oral supplementation of honey (BDL + honey) 10 g/kg per day. Liver, blood, spleen, mesenteric lymph nodes, and ileal samples were taken for microbiological, light and transmission electrone microscopic examination. RESULTS: Although the number of villi per centimeter and the height of the mucosa were higher in sham group, there was no statistically significant difference between sham and BDL + honey groups (P > 0.05). On the other hand, there was a statistically significant difference between BDL group and other groups (P < 0.05). The electron microscopic changes were also different between these groups. Sham and honey groups had similar incidence of bacterial translocation (P > 0.05). BDL group had significantly higher rates of bacterial translocation as compared with sham and honey groups. Bacterial translocation was predominantly detected in mesenteric lymph nodes. CONCLUSION: Supplementation of honey in presence of obstructive jaundice ameliorates bacterial translocation and improves ileal morphology. PMID:18528939

[Obstructed hemivagina and ipsilateral renal anomaly: unusual cause of piocolpos. Report a case and review of literature ].

PubMed

Cortés-Contreras, Diana Karen; Juárez-Cruz, Patricio Manuel; Vázquez-Flores, José; Vázquez-Flores, Al David

2014-10-01

OHVIRA (Obstructed hemivagina and ipsilateral renal anomaly) by acronym and abbreviations in English or Herlyn Werner Wunderlich syndrome is a rare congenital malformation caused by an alteration in the Mullerian ducts and Wolffian Ducts. Which is characterized by a triad: uterus didelphys, obstructed and ipsilateral renal agenesis hemivagina still uncertain etiology. Patients are usually asymptomatic until menarche where the most common clinical presentation is pelvic pain, followed by a vaginal or abdominal mass, normal menstrual periods, infertility, and vaginal discharge rarely appears. The case of a female patient of 15 years, nubile with chronic fetid vaginal discharge, initially diagnosed and treated as pelvic inflammatory disease occurs, however because it is an exceptional condition with the background of the patient, by complementary studies were conducted where pelvic ultrasound revealed pyocolpos and absence of left kidney, uterus didelphys, blind hemivagina by other imaging studies, where we could integrate Herlyn-Werner-Wunderlich syndrome. In conclusion, abnormalities in the development of the Miillerian ducts are difficult to diagnose early, so you must have the embryological knowledge, conduct thorough clinical assessment and detailed picture in whom the coridition is suspected to identify malformations coexisting urinary tract and vaginal defects with the importance of preserving reproductive success through appropriate planning of surgical approach, given that the fertility rate in these patients is comparable to the average.

Effect of sılymarın on oxıdatıve stress and lıver hıstopathology ın experımental obstructıve jaundıce model.

PubMed

Onalan, Ali Kemal; Tuncal, Salih; Kilicoglu, Sibel; Celepli, Salih; Durak, Esra; Kilicoglu, Bulent; Devrim, Erdinc; Barlas, Aziz Mutlu; Kismet, Kemal

2016-12-01

To investigate the effect of silymarin on oxidative stress and hepatic injury induced by obstructive jaundice in an experimental model. Thirty Wistar-Albino type female rats were divided into 3 groups each including 10 rats. Only laparotomy was performed in group 1. Bile duct ligation was performed in group 2. In group 3, bile duct ligation was performed and orogastic silymarin 300 mg/kg/day dose was given for seven days. At the end of seven days, rats were sacrificed. The blood and liver tissue samples were taken to be examined biochemically and histopathologically. The plasma and liver levels of malondialdehyde were significantly lower in silymarin group than in the bile duct ligated group. Although liver levels of GSH were significantly higher in silymarin group than in the bile duct ligated group, there was no significant difference between the plasma GSH levels of these groups. In silymarin group; the enlargement of hepatocytes, dilatation of canaliculi and the edema were regressed. Silymarin diminished the harmful effects of obstructive jaundice on liver.

Patent vitellointestinal duct

PubMed Central

Agrawal, Sanwar; Memon, Ameen

2010-01-01

During the 3rd week of intrauterine life there is a communication between the intraembryonic gut and the yolk sac. As the development proceeds this communication narrows into a tube known as the vitellointestinal duct (VID). With the establishment of placental nutrition this duct usually becomes obliterated by the end of the 7th week of intrauterine life. In about 2% of humans this duct persists and gives rise to a group of anomalies of which Meckel's diverticulum is the commonest and complete patency of the duct is the rarest.1 We report a case of a 4-month-old infant who presented with umbilical polyp, discharge from the umbilicus, significant dehydration and failure to thrive because of complete patency of the VID PMID:22778111

Duct-to-duct biliary reconstruction after radical resection of Bismuth IIIa hilar cholangiocarcinoma.

PubMed

Wu, Wen-Guang; Gu, Jun; Dong, Ping; Lu, Jian-Hua; Li, Mao-Lan; Wu, Xiang-Song; Yang, Jia-Hua; Zhang, Lin; Ding, Qi-Chen; Weng, Hao; Ding, Qian; Liu, Ying-Bin

2013-04-21

At present, radical resection remains the only effective treatment for patients with hilar cholangiocarcinoma. The surgical approach for R0 resection of hilar cholangiocarcinoma is complex and diverse, but for the biliary reconstruction after resection, almost all surgeons use Roux-en-Y hepaticojejunostomy. A viable alternative to Roux-en-Y reconstruction after radical resection of hilar cholangiocarcinoma has not yet been proposed. We report a case of performing duct-to-duct biliary reconstruction after radical resection of Bismuth IIIa hilar cholangiocarcinoma. End-to-end anastomosis between the left hepatic duct and the distal common bile duct was used for the biliary reconstruction, and a single-layer continuous suture was performed along the bile duct using 5-0 prolene. The patient was discharged favorably without biliary fistula 2 wk later. Evidence for tumor recurrence was not found after an 18 mo follow-up. Performing bile duct end-to-end anastomosis in hilar cholangiocarcinoma can simplify the complex digestive tract reconstruction process.

A case of recurrent cholangitis after bile duct injury during laparoscopic cholecystectomy: value of scintigraphy with Tc-99m GSA and hepatobiliary scintigraphy for indication of lobectomy.

PubMed

Nishiguchi, S; Shiomi, S; Sasaki, N; Iwata, Y; Tanaka, H; Kubo, S; Hirohashi, K; Ochi, H

2000-10-01

A 39-year-old woman with acute cholecystitis and gallstones underwent laparoscopic cholecystectomy. She suffered from recurrent episodes of cholangitis due to injury of the major bile ducts during laparoscopic cholecystectomy. Hepatobiliary scintigraphy with Tc-99m Sn-N-pyridoxyl-5-methyltryptophan was performed. Although normal bile excretion was found from the left hepatic duct to the percutaneous transhepatic biliary drainage (PTBD) tube, excretion from the right hepatic lobe was prolonged. Scintigraphy with Tc-99m diethylenetriaminepentaacetic acid-galactosyl human serum albumin demonstrated atrophy of the right hepatic lobe and enlargement of the left hepatic lobe. Cholangiography via the PTBD tube revealed complete obstruction of the left hepatico-jejunal anastomosis and could not enhance the right intrahepatic bile duct. A right hepatic lobectomy was performed because of the atrophy, glissonitis and the absence of an appropriate bile duct for reconstruction. Postoperatively she was active and exhibited no evidence of recurrent cholangitis.

Radiopaque biodegradable stent for duct-to-duct biliary reconstruction in pigs.

PubMed

Tanimoto, Yoshisato; Tashiro, Hirotaka; Mikuriya, Yoshihiro; Kuroda, Shintaro; Hashimoto, Masakazu; Kobayashi, Tsuyoshi; Taniura, Tokunori; Ohdan, Hideki

2016-06-01

Biliary stricture is a common cause of morbidity after liver transplantation. We previously developed a duct-to-duct biliary anastomosis technique using a biodegradable stent tube and confirmed the feasibility and safety of biliary stent use. However, the duration and mechanism of biliary stent absorption in the common bile duct remain unclear. Radiopaque biodegradable biliary stents were created using a copolymer of L-lactide and ε-caprolactone (70: 30) and coated with barium sulfate. Stents were surgically implanted in the common bile duct of 11 pigs. Liver function tests and computed tomography (CT) scans were performed postoperatively, and autopsies were conducted 6 months after biliary stent implantation. After the surgery, all 11 pigs had normal liver function and survived without any significant complications such as biliary leakage. A CT scan at 2 months post-procedure showed that the biliary stents were located in the hilum of the liver. The stents were not visible by CT scan at the 6-month follow-up examination. The surgical implantation of radiopaque biodegradable biliary stents in biliary surgery represents a new option for duct-to-duct biliary reconstruction. This technique appears to be feasible and safe and is not associated with any significant biliary complications. The advantage of coated biliary stent use is that it may be visualized using abdominal radiography such as CT.

Reciprocity principle in duct acoustics

NASA Technical Reports Server (NTRS)

Cho, Y.-C.

1979-01-01

Various reciprocity relations in duct acoustics have been derived on the basis of the spatial reciprocity principle implied in Green's functions for linear waves. The derivation includes the reciprocity relations between mode conversion coefficients for reflection and transmission in nonuniform ducts, and the relation between the radiation of a mode from an arbitrarily terminated duct and the absorption of an externally incident plane wave by the duct. Such relations are well defined as long as the systems remain linear, regardless of acoustic properties of duct nonuniformities which cause the mode conversions.

Bile duct hamartomas (von Mayenburg complexes) mimicking liver metastases from bile duct cancer: MRC findings

PubMed Central

Nagano, Yasuhiko; Matsuo, Kenichi; Gorai, Katsuya; Sugimori, Kazuya; Kunisaki, Chikara; Ike, Hideyuki; Tanaka, Katsuaki; Imada, Toshio; Shimada, Hiroshi

2006-01-01

We present a case of a 72-year-old man with a common bile duct cancer, who was initially believed to have multiple liver metastases based on computed tomography findings, and in whom magnetic resonance cholangiography (MRC) revealed a diagnosis of bile duct hamartomas. At exploration for pancreaticoduodenectomy, liver palpation revealed disseminated nodules at the surface of the liver. These nodules showed gray-white nodular lesions of about 0.5 cm in diameter scattered on the surface of both liver lobes, which were looked like multiple liver metastases from bile duct cancer. Frozen section of the liver biopsy disclosed multiple bile ducts with slightly dilated lumens embedded in the collagenous stroma characteristics of multiple bile duct hamartomas (BDHs). Only two reports have described the MRC features of bile duct hamartomas. Of all imaging procedures, MRC provides the most relevant features for the imaging diagnosis of bile duct hamartomas. PMID:16534895

Bile Duct Cancer

MedlinePlus

... the liver get rid of toxins and wastes. Bile duct cancer is rare. It can happen in the parts ... Itchy skin Fever Abdominal pain Tests to diagnose bile duct cancer may include a physical exam, imaging tests of ...

Reference values of MRI measurements of the common bile duct and pancreatic duct in children.

PubMed

Gwal, Kriti; Bedoya, Maria A; Patel, Neal; Rambhatla, Siri J; Darge, Kassa; Sreedharan, Ram R; Anupindi, Sudha A

2015-07-01

Magnetic resonance imaging/cholangiopancreatography (MRI/MRCP) is now an essential imaging modality for the evaluation of biliary and pancreatic pathology in children, but there are no data depicting the normal diameters of the common bile duct (CBD) and pancreatic duct. Recognition of abnormal duct size is important and the increasing use of MRCP necessitates normal MRI measurements. To present normal MRI measurements for the common bile duct and pancreatic duct in children. In this retrospective study we searched all children ages birth to 10 years in our MR urography (MRU) database from 2006 until 2013. We excluded children with a history of hepatobiliary or pancreatic surgery. We stratified 204 children into five age groups and retrospectively measured the CBD and the pancreatic duct on 2-D axial and 3-D coronal T2-weighted sequences. We performed statistical analysis, using logistic and linear regressions to detect the age association of the visibility and size of the duct measurements. We used non-parametric tests to detect gender and imaging plane differences. Our study included 204 children, 106 (52%) boys and 98 (48%) girls, with a median age of 33 months (range 0-119 months). The children were distributed into five age groups. The common bile duct was visible in all children in all age groups. The pancreatic duct was significantly less visible in the youngest children, group 1 (54/67, 80.5%; P = 0.003) than in the oldest children, group 5 (22/22, 100%). In group 2 the pancreatic duct was seen in 19/21 (90.4%), in group 3 52/55 (94.5%), and in group 4 39/39 (100%). All duct measurements increased with age (P < 0.001; r-value > 0.423), and the incremental differences between ages were significant. The measurement variations between the axial and coronal planes were statistically significant (P < 0.001); however these differences were fractions of millimeters. For example, in group 1 the mean coronal measurement of the CBD was 2.1 mm and

Bile duct stricture

MedlinePlus

... duct, the tube that moves bile from the liver to the small intestine. Bile is a substance that helps with digestion. ... causes of this condition include: Cancer of the bile duct, liver or pancreas Damage and scarring due to a ...

Percutaneous Transhepatic Biliary Stenting with Uncovered Self-Expandable Metallic Stents in Patients with Malignant Biliary Obstruction - Efficacy and Survival Analysis.

PubMed

Pranculis, Andrius; Kievišas, Mantas; Kievišienė, Lina; Vaičius, Artūras; Vanagas, Tomas; Kaupas, Rytis Stasys; Dambrauskas, Žilvinas

2017-01-01

The aim of this study was to assess short- and long-term outcomes of malignant biliary obstruction (MBO) treatment by percutaneous transhepatic biliary stenting (PTBS) with uncovered selfexpandable metallic stents (SEMS), and to identify predictors of survival. A nine-year, single-centre study from a prospectively collected database included 222 patients with inoperable MBO treated by PTBS with uncovered nitinol SEMS. Technical and clinical success rates were 95.9% and 82.4%, respectively. The total rate of postprocedural complications was 14.4%. The mean durations of the primary and secondary stent patency were 114.7±15.1 and 146.4±21.2 days, respectively. The 30-day mortality rate was 15.3% with no procedure-related deaths. The mean estimated length of survival was 143.3±20.6 days. Independent predictors increasing the risk of death included higher than 115 μmol/L serum bilirubin 2-5 days after biliary stenting (HR 3.274, P =0.019), distal (non-hilar) obstruction of the bile ducts (HR 3.711, P =0.008), Bismuth-Corlette type IV stricture (HR 2.082, P =0.008), obstruction due to gallbladder cancer (HR 31.029, P =0.012) and only partial drainage of liver parenchyma (HR 4.158, P =0.040). PTBS with uncovered SEMS is an effective and safe method for palliative treatment of MBO. Serum bilirubin higher than 115 μmol/L 2-5 days after the procedure has a significant negative impact on patients' survival. Lower survival is also determined by distal bile duct obstruction, Bismuth- Corlette type IV stricture, biliary obstruction caused by gallbladder cancer and when only partial liver drainage is applied.

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

PubMed

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

2005-01-01

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

Sealing ducts to save energy

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

Siuru, B.

1996-07-01

Large amounts of energy are wasted when heat leaks through ductwork located in uninsulated spaces. The Electric Power Research INstitute recently did a study that accurately measured these losses, then substantially reduced them by sealing the leaky ductwork. Six homes in the Pacific Northwest with significant duct leakage to the outside were selected for the study. The homes had electric resistance or heat pump, forced-air heating systems with a major portion of the supply and return ductwork in crawl spaces, attics, garages, etc. Measurements of duct leakage and heating system efficiency were done on all the homes before starting themore » duct sealing. Retrofitting included finding holes, gaps, cracks and disconnected joints in supply and return ducts as well as in plenums. When necessary, plenums were cut open for repairs. Leaks were sealed with Latex mastic and fiberglass tape. Outside ducts were covered or wrapped with insulation. Unducted returns were sealed with duct board. In some cases, leakage was corrected by merely reconnecting ducts and boots.« less

Ducted fuel injection

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

Mueller, Charles J.

Various technologies presented herein relate to enhancing mixing inside a combustion chamber to form one or more locally premixed mixtures comprising fuel and charge-gas with low peak fuel to charge-gas ratios to enable minimal, or no, generation of soot and other undesired emissions during ignition and subsequent combustion of the locally premixed mixtures. To enable sufficient mixing of the fuel and charge-gas, a jet of fuel can be directed to pass through a bore of a duct causing charge-gas to be drawn into the bore creating turbulence to mix the fuel and the drawn charge-gas. The duct can be locatedmore » proximate to an opening in a tip of a fuel injector. The duct can comprise of one or more holes along its length to enable charge-gas to be drawn into the bore, and further, the duct can cool the fuel and/or charge-gas prior to combustion.« less

Optimizing Electrospray Interfaces Using Slowly Diverging Conical Duct (ConDuct) Electrodes

PubMed Central

Krutchinsky, Andrew N.; Padovan, Júlio C.; Cohen, Herbert; Chait, Brian T.

2015-01-01

We demonstrate that the efficiency of ion transmission from atmosphere to vacuum through stainless steel electrodes that contain slowly divergent conical duct (ConDuct) channels can be close to 100%. Here, we explore the properties of 2.5 cm long electrodes with angles of divergence of 0°, 1°, 2°, 3°, 5°, 8°, 13°, and 21°, respectively. The ion transmission efficiency was observed to jump from 10–20% for the 0° (straight) channels to 90–95% for channels with an angle of divergence as small as 1°. Furthermore, the 2–3° ConDuct electrodes produced extraordinarily low divergence ion beams that propagated in a laser-like fashion over long distances in vacuum. To take advantage of these newly discovered properties, we constructed a novel atmosphere-to-vacuum ion interface utilizing a 2° ConDuct as an inlet electrode and compared its ion transmission efficiency with that of the interface used in the commercial (Thermo) Velos Orbitrap and Q Exactive mass spectrometers. We observed that the ConDuct interface transmitted up to 17 times more ions than the commercial reference interface and also yielded improved signal-to-noise mass spectra of peptides. We infer from these results that the performance of many current atmosphere-tovacuum interfaces utilizing metal capillaries can be substantially improved by replacing them with 1° or 2° metal ConDuct electrodes, which should preserve the convenience of supplying ion desolvation energy by heating the electrode while greatly increasing the efficiency of ion transmission into the mass spectrometer. PMID:25667060

Optimizing Electrospray Interfaces Using Slowly Diverging Conical Duct (ConDuct) Electrodes

NASA Astrophysics Data System (ADS)

Krutchinsky, Andrew N.; Padovan, Júlio C.; Cohen, Herbert; Chait, Brian T.

2015-04-01

We demonstrate that the efficiency of ion transmission from atmosphere to vacuum through stainless steel electrodes that contain slowly divergent conical duct (ConDuct) channels can be close to 100%. Here, we explore the properties of 2.5-cm-long electrodes with angles of divergence of 0°, 1°, 2°, 3°, 5°, 8°, 13°, and 21°, respectively. The ion transmission efficiency was observed to jump from 10-20% for the 0° (straight) channels to 90-95% for channels with an angle of divergence as small as 1°. Furthermore, the 2-3° ConDuct electrodes produced extraordinarily low divergence ion beams that propagated in a laser-like fashion over long distances in vacuum. To take advantage of these newly discovered properties, we constructed a novel atmosphere-to-vacuum ion interface utilizing a 2° ConDuct as an inlet electrode and compared its ion transmission efficiency with that of the interface used in the commercial (Thermo Fisher Scientific, San Jose, CA, USA) Velos Orbitrap and Q Exactive mass spectrometers. We observed that the ConDuct interface transmitted up to 17 times more ions than the commercial reference interface and also yielded improved signal-to-noise mass spectra of peptides. We infer from these results that the performance of many current atmosphere-to-vacuum interfaces utilizing metal capillaries can be substantially improved by replacing them with 1° or 2° metal ConDuct electrodes, which should preserve the convenience of supplying ion desolvation energy by heating the electrode while greatly increasing the efficiency of ion transmission into the mass spectrometer.

PMR Graphite Engine Duct Development

NASA Technical Reports Server (NTRS)

Stotler, C. L.; Yokel, S. A.

1989-01-01

The objective was to demonstrate the cost and weight advantages that could be obtained by utilizing the graphite/PMR15 material system to replace titanium in selected turbofan engine applications. The first component to be selected as a basis for evaluation was the outer bypass duct of the General Electric F404 engine. The operating environment of this duct was defined and then an extensive mechanical and physical property test program was conducted using material made by processing techniques which were also established by this program. Based on these properties, design concepts to fabricate a composite version of the duct were established and two complete ducts fabricated. One of these ducts was proof pressure tested and then run successfully on a factory test engine for over 1900 hours. The second duct was static tested to 210 percent design limit load without failure. An improved design was then developed which utilized integral composite end flanges. A complete duct was fabricated and successfully proof pressure tested. The net results of this effort showed that a composite version of the outer duct would be 14 percent lighter and 30 percent less expensive that the titanium duct. The other type of structure chosen for investigation was the F404 fan stator assembly, including the fan stator vanes. It was concluded that it was feasible to utilize composite materials for this type structure but that the requirements imposed by replacing an existing metal design resulted in an inefficient composite design. It was concluded that if composites were to be effectively used in this type structure, the design must be tailored for composite application from the outset.

Simple resection of the lesion bile duct branch for treatment of regional hepatic bile duct stones

PubMed Central

Enliang, Li; Rongshou, Wu; Shidai, Shi; Jingling, Zhang; Qian, Feng; Wenjun, Liao; Linquan, Wu

2017-01-01

Abstract To evaluate the effectiveness and safety of simple resections of bile duct branch lesions for the treatment of regional hepatic bile duct stones. A retrospective analysis of the clinical data from patients in our hospital from November 2008 to November 2015, who only underwent a simple resection of the lesion bile duct branch. The patients’ clinical characteristics, surgical features, postoperative complications, stone clear rate, residual stone rate, and recurrence stone rate were analyzed. This study of 32 patients included 13 males and 19 females with intrahepatic bile duct stones confined to the right hepatic bile duct branch. The intraoperative blood loss, operation time, and postoperative hospital stay were 478.0 ± 86.5, 210.7 ± 6.6, and 10.8 ± 3.5, respectively. Postoperative complications occurred in 6 patients (18.8%), all of whom recovered with conservative management. There were no deaths during hospitalization. The intraoperative stone clearance rate was 95.8%. Three patients had a recurrence of stones at a mean of 22 months of follow-up (range, 4–36 months). Simple resection of bile duct branch lesions is safe and feasible for patients who have regional hepatic bile duct stones limited to the right hepatic bile duct branches. PMID:28682899

Turbofan aft duct suppressor study

NASA Technical Reports Server (NTRS)

Syed, A. A.; Motsinger, R. E.; Fiske, G. H.; Joshi, M. C.; Kraft, R. E.

1983-01-01

Suppressions due to acoustic treatment in the annular exhaust duct of a model fan were theoretically predicted and compared with measured suppressions. The predictions are based on the modal analysis of sound propagation in a straight annular flow duct with segmented treatment. Modal distributions of the fan noise source (fan-stator interaction only) were measured using in-duct modal probes. The flow profiles were also measured in the vicinity of the modal probes. The acoustic impedance of the single degree of freedom treatment was measured in the presence of grazing flow. The measured values of mode distribution of the fan noise source, the flow velocity profile and the acoustic impedance of the treatment in the duct were used as input to the prediction program. The predicted suppressions, under the assumption of uniform flow in the duct, compared well with the suppressions measured in the duct for all test conditions. The interaction modes generated by the rotor-stator interaction spanned a cut-off ratio range from nearly 1 to 7.

Eversion Bile Duct Anastomosis: A Safe Alternative for Bile Duct Size Discrepancy in Deceased Donor Liver Transplantation.

PubMed

Leal-Leyte, Pilar; McKenna, Greg J; Ruiz, Richard M; Anthony, Tiffany L; Saracino, Giovanna; Giuliano, Testa; Klintmalm, Goran B; Kim, Peter Tw

2018-04-10

Introduction Bile duct size discrepancy in liver transplantation may increase the risk of biliary complications. The aim of this study was to evaluate the safety and outcomes of the eversion bile duct anastomosis technique in deceased donor liver transplantation (DDLT) with duct to duct anastomosis. Methods A total of 210 patients who received a DDLT with duct to duct anastomosis from 2012 to 2017 were divided into two groups: those who had eversion bile duct anastomosis (N=70) and standard bile duct anastomosis (N=140). Biliary complications rates were compared between the two groups. Results There was no difference in the cumulative incidence of biliary strictures (P=0.20) and leaks (P=0.17) between the two groups. The biliary complication rate in the eversion group was 14.3% and 11.4% in the standard anastomosis group. All the biliary complications in the eversion group were managed with endoscopic stenting. A severe size mismatch (≥3:1 ratio) was associated with a significantly higher incidence of biliary strictures (44.4%) compared to 2:1 ratio (8.2%), (P=0.002). Conclusion The use of the eversion technique is a safe alternative for bile duct discrepancy in deceased donor liver transplantation; however, severe bile duct size mismatch may be a risk factor for biliary strictures with such technique. This article is protected by copyright. All rights reserved. © 2018 by the American Association for the Study of Liver Diseases.

Endosonography for suspected obstructive jaundice with no definite pathology on ultrasonography.

PubMed

Chen, Chien-Hua; Yang, Chi-Chieh; Yeh, Yung-Hsiang; Yang, Tsang; Chung, Tieh-Chi

2015-09-01

Ultrasonography (US) cannot demonstrate all the etiologies of biliary tract dilatation in patients with jaundice. Thus, we evaluated the etiologic yield of endosonography (EUS) for suspected obstructive jaundice when no definite pathology was found on US. Additionally, we sought to identify the predictors of the most common etiologies. We performed a retrospective review of 123 consecutive patients who had undergone EUS for suspected obstructive jaundice when no definite pathology was identified on US. The most common diagnoses included no pathological obstruction (n = 43), pancreatobiliary malignancy (n = 41), and choledocholithiasis (n = 28). Pancreatobiliary malignancy was associated with common bile duct (CBD) dilatation, and fever and elevated alanine aminotransferase were predictors of choledocholithiasis (p < 0.05). The accuracy of EUS was 95.9% (118/123) for overall cause of suspected obstructive jaundice, 100% (40/40) for no pathological finding, 100% (23/23) for ampullary cancer, 100% (13/13) for pancreatic cancer, 75% (3/4) for CBD cancer, and 92.9% (26/28) for choledocholithiasis, respectively. Besides the two patients with focal chronic pancreatitis misdiagnosed as with pancreatic cancer, EUS missed the lesions in one CBD cancer patient and two patients with choledocholithiasis. The overall accuracy of EUS in ascertaining pancreatobiliary malignancy and choledocholithiasis was comparable (97.6%, 40/41 vs. 92.9%, 26/28; p > 0.05). Marked CBD dilatation (≥12 mm) should remind us of the high risk of malignancy, and the presence of CBD dilatation and fever is suggestive of choledocholithiasis. Negative EUS findings cannot assure any pathological obstruction in patients with clinically suspected obstructive jaundice. Copyright © 2013. Published by Elsevier B.V.

Worsening cholestasis and possible cefuroxime-induced liver injury following "successful" therapeutic endoscopic retrograde cholangiopancreatography for a distal common bile duct stone: a case report.

PubMed

Niriella, Madunil Anuk; Kumarasena, Ravindu Sujeewa; Dassanayake, Anuradha Supun; Pathirana, Aloka; de Silva Hewavisenthi, Janaki; de Silva, Hithanadura Janaka

2016-12-21

Cefuroxime very rarely causes drug-induced liver injury. We present a case of a patient with paradoxical worsening of jaundice caused by cefuroxime-induced cholestasis following therapeutic endoscopic retrograde cholangiopancreatography for a distal common bile duct stone. A 51-year-old, previously healthy Sri Lankan man presented to our hospital with obstructive jaundice caused by a distal common bile duct stone. Endoscopic retrograde cholangiopancreatography with stone extraction, common bile duct clearance, and stenting failed to improve the cholestasis, with paradoxical worsening of his jaundice. A liver biopsy revealed features of drug-induced intrahepatic cholestasis. Although his case was complicated by an episode of cholangitis, the patient made a complete recovery in 4 months with supportive treatment and withdrawal of the offending drug. This case highlights a very rare drug-induced liver injury caused by cefuroxime as well as our approach to treating a patient with paradoxical worsening of jaundice after therapeutic endoscopic retrograde cholangiopancreatography.

Ultrasonographic and clinicopathologic features of segmental dilatations of the common bile duct in four cats

PubMed Central

Spain, Heather N; Penninck, Dominique G; Webster, Cynthia RL; Daure, Evence; Jennings, Samuel H

2017-01-01

Case series summary This case series documents ultrasonographic and clinicopathologic features of four cats with marked segmental dilatations of the common bile duct (CBD). All cats had additional ultrasonographic changes to the hepatobiliary system, including hepatomegaly, tubular to saccular intra/extrahepatic biliary duct dilatation and biliary debris accumulation. Based on all available data the presence of extrahepatic biliary duct obstruction (EHBDO) was ruled out in 3/4 cases and was equivocal in one case. One cat underwent re-routing surgery to address the CBD dilatation after multiple recurrent infections, one cat was euthanized and had a post-mortem examination and two cats were medically managed with antibiotics, liver protectants, gastroprotectants and cholerectics. Relevance and novel information The ultrasonographic features of the CBD in this population of cats were supportive of choledochal cysts (CCs). The maximal diameter of the CBD dilatations exceeded 5 mm in all cases, a sign that has been previously reported to be consistent with EHBDO. In our study, dilatations were segmental rather than diffuse. Given the high morbidity and mortality associated with hepatobiliary surgery in cats, segmental dilatation of the CBD should not prompt emergency surgery. Some cats may respond to medical management. Careful planning for cyst resection was beneficial in one cat. Evaluation of CC morphology (eg, size, location, concurrent intrahepatic anomalies) may assist in selecting cats that could benefit from surgical intervention. PMID:28680700

Double-duct liquid metal magnetohydrodynamic engine

DOEpatents

Haaland, Carsten M.

1995-01-01

An internal combustion, liquid metal (LM) magnetohydrodynamic (MHD) engine and an alternating current (AC) magnetohydrodynamic generator, are used in combination to provide useful AC electric energy output. The engine design has-four pistons and a double duct configuration, with each duct containing sodium potassium liquid metal confined between free pistons located at either end of the duct. The liquid metal is forced to flow back and forth in the duct by the movement of the pistons, which are alternatively driven by an internal combustion process. In the MHD generator, the two LM-MHD ducts pass in close proximity through a Hartmann duct with output transformer. AC power is produced by operating the engine with the liquid metal in the two generator ducts always flowing in counter directions. The amount of liquid metal maintained in the ducts may be varied. This provides a variable stroke length for the pistons. The engine/generator provides variable AC power at variable frequencies that correspond to the power demands of the vehicular propulsion. Also the engine should maintain nearly constant efficiency throughout the range of power usage. Automobiles and trucks could be powered by the invention, with no transmission or power converter devices being required.

Double-duct liquid metal magnetohydrodynamic engine

DOEpatents

Haaland, Carsten M.

1997-01-01

An internal combustion, liquid metal (LM) magnetohydrodynamic (MHD) engine and an alternating current (AC) magnetohydrodynamic generator, are used in combination to provide useful AC electric energy output. The engine design has four pistons and a double duct configuration, with each duct containing sodium potassium liquid metal confined between free pistons located at either end of the duct. The liquid metal is forced to flow back and forth in the duct by the movement of the pistons, which are alternatively driven by an internal combustion process. In the MHD generator, the two LM-MHD ducts pass in close proximity through a Hartmann duct with output transformer. AC power is produced by operating the engine with the liquid metal in the two generator ducts always flowing in counter directions. The amount of liquid metal maintained in the ducts may be varied. This provides a variable stroke length for the pistons. The engine/generator provides variable AC power at variable frequencies that correspond to the power demands of the vehicular propulsion. Also the engine should maintain nearly constant efficiency throughout the range of power usage. Automobiles and trucks could be powered by the invention, with no transmission or power converter devices being required.

Percutaneous Transhepatic Biliary Stenting with Uncovered Self-Expandable Metallic Stents in Patients with Malignant Biliary Obstruction – Efficacy and Survival Analysis

PubMed Central

Pranculis, Andrius; Kievišienė, Lina; Vaičius, Artūras; Vanagas, Tomas; Kaupas, Rytis Stasys; Dambrauskas, Žilvinas

2017-01-01

Summary Background The aim of this study was to assess short- and long-term outcomes of malignant biliary obstruction (MBO) treatment by percutaneous transhepatic biliary stenting (PTBS) with uncovered selfexpandable metallic stents (SEMS), and to identify predictors of survival. Material/Methods A nine-year, single-centre study from a prospectively collected database included 222 patients with inoperable MBO treated by PTBS with uncovered nitinol SEMS. Results Technical and clinical success rates were 95.9% and 82.4%, respectively. The total rate of postprocedural complications was 14.4%. The mean durations of the primary and secondary stent patency were 114.7±15.1 and 146.4±21.2 days, respectively. The 30-day mortality rate was 15.3% with no procedure-related deaths. The mean estimated length of survival was 143.3±20.6 days. Independent predictors increasing the risk of death included higher than 115 μmol/L serum bilirubin 2–5 days after biliary stenting (HR 3.274, P=0.019), distal (non-hilar) obstruction of the bile ducts (HR 3.711, P=0.008), Bismuth-Corlette type IV stricture (HR 2.082, P=0.008), obstruction due to gallbladder cancer (HR 31.029, P=0.012) and only partial drainage of liver parenchyma (HR 4.158, P=0.040). Conclusions PTBS with uncovered SEMS is an effective and safe method for palliative treatment of MBO. Serum bilirubin higher than 115 μmol/L 2–5 days after the procedure has a significant negative impact on patients’ survival. Lower survival is also determined by distal bile duct obstruction, Bismuth– Corlette type IV stricture, biliary obstruction caused by gallbladder cancer and when only partial liver drainage is applied. PMID:29662569

Triple bypass for advanced pancreatic head cancer associated with biliary stricture, duodenal stenosis, and recurrent obstructive pancreatitis.

PubMed

Kudo, Yuzan; Sato, Norihiro; Tamura, Toshihisa; Hirata, Keiji

2016-12-01

Bypass surgery for cancer of the pancreatic head is usually done to palliate the obstructive symptoms in the biliary and/or digestive system. However, it is uncommon for patients to require pancreatic duct drainage for recurrent obstructive pancreatitis. In this article, we report a surgical technique of triple bypass consisting of Roux-en-Y hepaticojejunostomy, gastrojejunostomy, and pancreaticojejunostomy for advanced pancreatic cancer. A 76-year-old male patient with locally advanced and metastatic pancreatic head cancer was referred to our department for biliary stricture, duodenal stenosis, and recurrent obstructive pancreatitis associated with persistent pancreatic pseudocyst. In an attempt to resolve all these problems simultaneously, a triple bypass was performed. The patient survived and continued to receive chemotherapy for almost 1 year after surgery without any serious complications. Thus, triple bypass is a useful surgical technique that could relief symptoms and offer better quality of life to patients with advanced pancreatic cancer presenting with biliary stricture, duodenal stenosis, and severe obstructive pancreatitis difficult to treat by medication or endoscopic procedures.

Duct having oscillatory side wall

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

Sprouse, Kenneth M.

A pump system includes a particulate consolidator pump that has a pump outlet. A duct is coupled to the pump outlet. The duct has a wall that is coupled with an oscillator. The oscillator is operable to oscillate the wall at a controlled frequency. The controlled frequency is selected with respect to breaking static bridging of particulate in the duct due, at least in part, to consolidation of the particulate from a downstream check valve.

3 alpha-Hydroxylated bile acid profiles in clinically normal cats, cats with severe hepatic lipidosis, and cats with complete extrahepatic bile duct occlusion.

PubMed

Center, S A; Thompson, M; Guida, L

1993-05-01

Concentrations of 3 alpha-hydroxylated bile acids were measured in serum and urine of clinically normal (healthy) cats (n = 6), cats with severe hepatic lipidosis (n = 9), and cats with complete bile duct occlusion (n = 4). Bile acid concentrations were measured by use of a gradient flow high-performance liquid chromatography procedure with an acetonitrile and ammonium phosphate mobile phase and an in-line postanalytic column containing 3 alpha-hydroxy-steroid dehydrogenase and a fluorescence detector. Specific identification of all bile acid peaks was not completed; unidentified moieties were represented in terms of their elution time (in minutes). Significant differences in serum and urine bile acid concentrations, quantitative and proportional, were determined among groups of cats. Cats with hepatic lipidosis and bile duct occlusion had significantly (P > or = 0.05) greater total serum and urine bile acids concentrations than did healthy cats. The proportion of hydrophobic bile acids in serum, those eluting at > or = 400 minutes, was 1.9% for healthy cats, 3.3% for cats with lipidosis, and 5.4% for bile duct-obstructed cats. Both groups of ill cats had a broader spectrum of unidentified late-eluting serum bile acids than did healthy cats; the largest spectrum developed in bile duct-occluded cats.(ABSTRACT TRUNCATED AT 250 WORDS)

α7-nAChR Knockout Mice Decreases Biliary Hyperplasia and Liver Fibrosis in Cholestatic Bile-Duct Ligated Mice.

PubMed

Ehrlich, Laurent; O'Brien, April; Hall, Chad; White, Tori; Chen, Lixian; Wu, Nan; Venter, Julie; Scrushy, Marinda; Mubarak, Muhammad; Meng, Fanyin; Dostal, David; Wu, Chaodong; Lairmore, Terry C; Alpini, Gianfranco; Glaser, Shannon

2018-03-26

α7-nAChR is a nicotinic acetylcholine receptor (specifically expressed on hepatic stellate cells, Kupffer cells, and cholangiocytes) that regulates inflammation and apoptosis in the liver. Thus, targeting α7-nAChR may be therapeutic in biliary diseases. Bile-duct ligation (BDL) was performed on wild-type (WT) and α7-nAChR-/- mice. We first evaluated the expression of α7-nAChR by immunohistochemistry (IHC) in liver sections. IHC was also performed to assess intrahepatic bile-duct mass (IBDM), and Sirius Red staining was performed to quantify the amount of collagen deposition. Immunofluorescence was performed to assess co-localization of α7-nAChR with bile ducts (co-stained with CK-19) and hepatic stellate cells (HSCs) (co-stained with desmin). The mRNA expression of α7-nAChR, Ki67/PCNA (proliferation), fibrosis genes (TGF-β1, Fibronectin-1, Col1α1, and α-SMA), and inflammatory markers (IL-6, IL-1β, and TNFα) was measured by real-time PCR. Biliary TGF-β1 and hepatic CD68 (Kupffer cell marker) expression was assessed using IHC. α7-nAChR immunoreactivity was observed in both bile ducts and HSCs and increased following BDL. α7-nAChR-/- BDL mice exhibited decreased: (i) bile duct mass, liver fibrosis, and inflammation; and (ii) immunoreactivity of TGF-1 as well as expression of fibrosis genes compared to WT BDL mice. α7-nAChR activation triggers biliary proliferation and liver fibrosis and may be a therapeutic target in managing extra-hepatic biliary obstruction.

[Late stage stenoses of bile ducts after iatrogenic bile duct injuries following cholecystectomy].

PubMed

Bektas, H; Winny, M; Schrem, H; Becker, T; Klempnauer, J

2007-12-01

Iatrogenic bile duct injuries represent a severe complication after cholecystectomy. For the attending physician therapy and management of these injuries are a challenge. Inadequate and delayed treatment can lead to stenoses at a late stage, which can necessitate further surgical intervention. In a study data of 74 patients, who were treated in our clinic for bile duct injuries following cholecystectomy, were analysed retrospectively. A total of 8 patients with late stage bile duct strictures following iatrogenic bile duct injury including the subsequent therapy could be identified. The data of these patients were analysed in respect of cause and strategies to prevent late stage stenoses. In 62 patients the bile duct injury occurred following laparoscopic and in 12 patients following open cholecystectomy. In 16 patients the injury was combined with a vascular lesion. The interval between primary intervention and definitive therapy was 11 days in 53 patients and 1-15 years in 21 patients. In 8 patients the reason for the re-operation after a long interval (1-15 years) was a late stage stenosis. A hepatico-jejunostomy was performed subsequently and during follow-up 5 / 8 patients were symptom-free; 7 patients were re-operated due to a stenosed primary biliodigestive anastomosis and 3 patients each due to atrophy of the right liver lobe and recurrent cholangitis. One patient complained of recurrent cholangitis and a further patient of symptoms due to adhesions. If treated inadequately bile duct injuries occurring during cholecystectomy can in the long-term lead to considerable problems such as recurrent cholangitis, late stage stenoses and even to secondary biliary cirrhosis. Therefore, a complex inter-disciplinary therapeutic concept aiming at timely treatment is necessary.

T-EUS for Gastrointestinal Disorders: A Multicenter Registry

ClinicalTrials.gov

2017-02-16

Cholangiocarcinoma; Pancreatic Cancer; Bile Duct Cancer; Biliary Stricture; Biliary Obstruction; Stent Obstruction; Proximal Duct Stricture; Distal Duct Stricture; Ampullary Cancer; Biliary Sphincter Stenosis; Impacted Stones; Chronic Pancreatitis; Peri-ampullary Diverticula; Altered Anatomy

A Plug-and-Play Duct System Evaluation

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

Beach, Robert; Dickson, Bruce; Grisolia, Anthony

This report describes an air distribution system composed of a series of uniformly-sized ducts that terminate in rooms throughout the home and return to a central manifold, similar in fashion to a “home-run” cross-linked polyethylene plumbing system. With a well-designed manifold, each duct receives an equal static pressure potential for airflow from the air handling unit, and the number of needed ducts for each room are simply attached to fittings located on the manifold; in this sense, the system is plug-and-play (PnP). As indicated, all ducts in the PnP system are identical in size and small enough to fit inmore » the ceiling and wall cavities of a house (i.e., less than 3.5-in. outer diameter). These ducts are also more appropriately sized for the lower airflow requirements of modern, energy-efficient homes; therefore, the velocity of the air moving through the duct is between that of conventional duct systems (approximately 700 ft/min) and high-velocity systems (more than 1,500 ft/min) on the market today. The PnP duct system uses semi-rigid plastic pipes, which have a smooth inner wall and are straightforward to install correctly, resulting in a system that has minimal air leakage. However, plastic ducts are currently not accepted by code for use in residential buildings; therefore, the project team considered other duct materials for the system that are currently accepted by code, such as small-diameter, wirehelix, flexible ductwork.« less

A Plug-and-Play Duct System Evaluation

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

Beach, R.; Dickson, B.; Grisolia, A.

2017-07-01

This report describes an air distribution system composed of a series of uniformly-sized ducts that terminate in rooms throughout the home and return to a central manifold, similar in fashion to a “home-run” cross-linked polyethylene plumbing system. With a well-designed manifold, each duct receives an equal static pressure potential for airflow from the air handling unit, and the number of needed ducts for each room are simply attached to fittings located on the manifold; in this sense, the system is plug-and-play (PnP). As indicated, all ducts in the PnP system are identical in size and small enough to fit inmore » the ceiling and wall cavities of a house (i.e., less than 3.5-in. outer diameter). These ducts are also more appropriately sized for the lower airflow requirements of modern, energy-efficient homes; therefore, the velocity of the air moving through the duct is between that of conventional duct systems (approximately 700 ft/min) and high-velocity systems (more than 1,500 ft/min) on the market today. The PnP duct system uses semi-rigid plastic pipes, which have a smooth inner wall and are straightforward to install correctly, resulting in a system that has minimal air leakage. However, plastic ducts are currently not accepted by code for use in residential buildings; therefore, the project team considered other duct materials for the system that are currently accepted by code, such as small-diameter, wirehelix, flexible ductwork.« less

Computed tomography of the lacrimal drainage system: retrospective study of 107 cases of dacryostenosis.

PubMed

Francis, I C; Kappagoda, M B; Cole, I E; Bank, L; Dunn, G D

1999-05-01

To evaluate the role of computed tomography in patients with dacryostenosis. One hundred seven cases of dacryostenosis (94 patients) were assessed by thorough clinical and lacrimal history and examination, and lacrimal region computerized tomography (CT). The lacrimal drainage system examination included the state and position of the puncta; Jones testing; lacrimal syringing; and, in the latter half of the study, telescopic nasal endoscopy. The patients were drawn from the hospital outpatients and private office of the operating lacrimal surgeon in this series (I.C.F.). Of the 107 cases, 79 either underwent dacryocystorhinostomy surgery or had this planned. In 14 of the 107 cases (12 patients), preoperative CT led to an alteration of patient management, usually referral to an otolaryngologist for further evaluation or treatment. In addition to the detection of two tumors extrinsic to the sac, conditions such as ethmoiditis, lacrimal sac mucoceles, soft tissue opacity in the nasolacrimal duct, gross nasal polyposis, fungal sinusitis, and a dacryolith were observed by CT. Similar to the role of functional endoscopic sinus surgery in otolaryngology, CT imaging will become increasingly important in the assessment of many patients with symptoms of lacrimal drainage obstruction.

Transcanalicular laser-assisted dacryocystorhinostomy.

PubMed

Rosen, N; Barak, A; Rosner, M

1997-09-01

Current techniques of laser-assisted dacryocystorhinostomy are mostly endonasal. In this report, the authors describe their technique of laser-assisted dacryocystorhinostomy performed through the canaliculi and the surgical results they achieved. Fourteen patients with nasolacrimal duct obstruction underwent transcanalicular laser-assisted dacryocystorhinostomy. The bony ostium was perforated using a fiber optic-transmitting, giant-pulse Nd:YAG laser, with an energy of 0.5 to 4 J per pulse. The total energy used to create an ostium was 18 to 34 J. A silicone tube was inserted through the canaliculi and the ostium into the nasal cavity and kept in place for 5 to 7 months. Patients were observed for 18 to 22 months. Nine of the 14 patients (64%) reported the disappearance of epiphora following surgery. In 3 patients, no relief of epiphora was obtained. In 1 patient the operation was not completed because of severe nasal bleeding. In another, tearing began 12 months after surgery (6 months after tube removal). Transcanalicular laser-assisted dacryocystorhinostomy is a potentially useful method for performing dacryocystorhinostomy. Technical modifications and improvements are needed to increase the success rate.

Late effects of intraoperative radiation therapy on retroperitoneal tissues, intestine, and bile duct in a large animal model

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

Sindelar, W.F.; Tepper, J.E.; Kinslla, T.J.

1994-07-01

The late histopathological effects of intraoperative radiotherapy (IORT) on retroperitoneal tissues, intestine, and bile duct were investigated in dogs. Fourteen adult foxhounds were subjected to laparotomy and varying doses (0-45 Gy) of IORT (11 MeV electrons) delivered to retroperitoneal tissues including the great vessels and ureters, to a loop of defunctionalized small bowel, or to the extrahepatic bile duct. One control animal received an aortic transection and reanastomosis at the time of laparotomy; another control received laparotomy alone. This paper describes the late effects of single-fraction IORT occurring 3-5 years following treatment. Dogs receiving IORT to the retroperitoneum through amore » 4 X 15 cm portal showed few gross or histologic abnormalities at 20 Gy. At doses ranging from 30-45 Gy, radiation changes in normal tissues were consistently observed. Retroperitoneal fibrosis with encasement of the ureters and great vessels developed at doses {ge}30 Gy. Radiation changes were present in the aorta and vena cava at doses {ge}40 Gy. A 30 Gy dog developed an in-field malignant osteosarcoma at 3 years which invaded the vertebral column and compressed the spinal cord. A 40 Gy animal developed obstruction of the right ureter with fatal septic hydronephrosis at 4 years. Animals receiving IORT through a 5 cm IORT portal to an upper abdominal field which included a defunctionalized loop of small bowel, showed few gross or histologic abnormalities at a dose of 20 Gy. At 30 Gy, hyaline degeneration of the intestinal muscularis layer of the bowel occurred. At a dose of 45 Gy, internal intestinal fistulae developed. One 30 Gy animal developed right ureteral obstruction and hydronephrosis at 5 years. A dog receiving 30 Gy IORT through a 5 cm portal to the extrahepatic bile duct showed diffuse fibrosis through the gastroduodenal ligament. These canine studies contribute to the area of late tissue tolerance to IORT. 7 refs., 3 figs., 5 tabs.« less

Lightweight Forms for Epoxy/Aramid Ducts

NASA Technical Reports Server (NTRS)

Mix, E. W.; Anderson, A. N.; Bedford, Donald L., Sr.

1986-01-01

Aluminum mandrels easy to remove. Lightweight aluminum mandrel for shaping epoxy/aramid ducts simplifies and speeds production. In new process, glass-reinforced epoxy/aramid cloth wrapped on aluminum mandrel. Stainless-steel flanges and other hardware fitted on duct and held by simple tooling. Entire assembly placed in oven to cure epoxy. After curing, assembly placed in alkaline bath dissolves aluminum mandrel in about 4 hours. Epoxy/aramid shell ready for use as duct. Aluminum mandrel used to make ducts of various inside diameters up to 6 in. Standard aluminum forms used. Conventional tube-bending equipment produces requisite curves in mandrels.

Electromagnetic propagation in PEC and absorbing curved S-ducts

NASA Technical Reports Server (NTRS)

Baumeister, Kenneth J.

1988-01-01

A finite-element Galerkin formulation has been developed to study transverse magnetic (TM) wave propagation in 2-D S-curved ducts with both perfectly conducting and absorbing walls. The reflection and transmission at the entrances and the exits of the curved ducts are determined by coupling the finite-element solutions in the curved ducts to the eigenfunctions of an infinite, uniform, perfectly conducting duct. Example solutions are presented for a double mitred and S-ducts of various lengths. The length of the S-duct is found to significantly effect the reflective characteristics of the duct. Also, the effect of curvature on an absorbing duct is illustrated.

Non-traumatic perforation of common hepatic duct: Case report and review of literature HP.

PubMed

Atwez, Abdelaziz; Augustine, Matthew; Nottingham, James M

2017-01-01

Non-traumatic biliary perforation other than the gallbladder is extremely rare and most commonly seen in children in association with congenital biliary anomalies. We present a rare case of choledocholithiasis that progressed to spontaneous perforation of the common hepatic duct probably from ischemic necrosis caused by impaction of large biliary stones. A 62-year-old female presented with diarrhea and jaundice. She was found to have two 2.5cm stones in the common hepatic duct. Stones could not be extracted by ERCP, and placement of biliary stent was done to restore patency. The patient was lost to follow up and returned after three months with a new onset of similar symptoms. At that time ERCP and a stent change were done without resolution of the symptoms. Patient then underwent an open exploration and was found to have a free perforation in the lateral aspect of the common hepatic duct just at the bifurcation of the right and left hepatic radicals. Through this perforation stones were both extracted and cholangiogram showed free flow with the distal biliary stent. The stent was nowhere near the site of perforation which appeared to be caused by pressure necrosis from the impacted stones. Impacted stones in the biliary tree need to be extracted to avoid pressure necrosis and spontaneous perforation. ERCP and stent placement should be used only as temporizing measures to manage the acute obstructive phase. Definitive surgical intervention must follow initial biliary decompression to extract the impacted biliary stones and avoid complications. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Prospective evaluation of a newly designed T-configured stent graft system for palliative treatment of advanced hilar malignant biliary obstructions.

PubMed

Gwon, Dong Il; Ko, Gi-Young; Yoon, Hyun-Ki; Kim, Jin Hyoung; Lee, Jae Myeong; Ohm, Joon-Young; Sung, Kyu-Bo

2010-09-01

To investigate the technical and clinical safety and efficacy of using a newly designed T-configured stent graft for palliative treatment of advanced hilar malignant biliary obstructions. This is a prospective study that enrolled 30 patients who had malignant hilar obstructions from May 2007 to November 2008. All patients were treated with percutaneous transhepatic placement of two specially designed stent grafts in a T configuration. Technical success, evaluation of blocked branching ducts, complications, clinical success, stent patency time, and patient survival rates were analyzed. Stent graft deployment was technically successful in all patients. The bilirubin level and the bile duct diameter decreases were statistically significant after stent placement (P < .001), and all patients showed clinical improvement. Minor complications, including procedure-related complications (self-limiting hemobilia [n = 3], perihepatic biloma [n = 1], and acute pancreatitis [n = 1]) and rapidly resolving cholangitis (n = 5), occurred in ten patients (33.3%). Major complications, including acute cholecystitis, occurred in three patients (10%). Stent occlusion occurred in 12 patients (40%) after a mean period of 160 days (range, 82-307 days). The median survival and stent patency times were 334 days (range, 195.6-472.4 days) and 279 days (range, 194.7-363.3 days), respectively. There were no statistical differences in age, sex, Bismuth type, or number of blocked branching ducts. The initial results of percutaneous palliative treatment of advanced hilar malignancies with T-configured stent grafts suggest that they are safe and potentially clinically effective. Copyright 2010 SIR. Published by Elsevier Inc. All rights reserved.

The protective effects of pomegranate on liver and remote organs caused by experimental obstructive jaundice model.

PubMed

Yilmaz, E E; Arikanoğlu, Z; Turkoğlu, A; Kiliç, E; Yüksel, H; Gümüş, M

2016-01-01

We aimed to investigate the protective potential of pomegranate extract on the liver and remote organs in rats with obstructive jaundice. The rats were split into 4 groups. In Group 1 (G1) (sham group) rats, the common bile duct was mobilized without any ligation. Group 2 (G2) received a combination of the sham operation and synchronous treatment with pomegranate. Group 3 (G3) received common bile duct ligation (CBDL). Group 4 (G4) were subjected to CBDL and treatment with pomegranate. After 8 days, we measured total oxidative status (TOS) and antioxidant capacity in the rats' liver tissue and remote organs, and evaluated blood levels of malondialdehyde and total antioxidant capacity (TAC). G3 rats showed significantly raised malondialdehyde level as compared to G1 rats (p < 0.001). Following the pomegranate therapy, a decrease in malondialdehyde was observed (p = 0.015). TAC levels were significantly raised in the G3 rats compared to the G1 rats (p = 0.004). TAC levels dropped after pomegranate therapy (p = 0.011). CBDL caused elevated TOS levels in the liver and remote organs, with a statistically significant increase in the lung tissue (p = 0.002). TOS levels in the CBDL groups decreased after pomegranate treatment (p < 0.001). This study reveals the marked protective effect of pomegranate on the liver and remote organs in obstructive jaundice.

Intraoral Salivary Duct Cyst: Clinical and Histopathologic Features of 177 Cases.

PubMed

Stojanov, Ivan J; Malik, Umer A; Woo, Sook-Bin

2017-12-01

The salivary duct cyst (SDC) is a reactive ductal ectasia most frequently seen in major salivary glands, and likely caused by obstruction. The aim of this study is to define the clinical and histopathologic spectrum of intraoral SDCs. Cases were retrieved from the archives of Harvard School of Dental Medicine/StrataDx, Inc. from January 2012 to August 2014. There were 177 cases of which 103 (58.2%) occurred in females, with a median age of 56 (range 2-95). Approximately half of cases (45.8%) presented in the area of the buccal mucosa, lower lip mucosa, or mandibular vestibule, and 23.2% presented in the floor of mouth. SDCs were lined at least focally by 1-2 layers of cuboidal/columnar epithelium in 85.3% of cases and showed varying degrees of metaplasia (oncocytic, mucous cell, squamous, ciliated, apocrine-like) in 68.4% of cases. Intraluminal mucous stasis was present in 41.8% of SDCs, incipient calcification was present within 4.5% of SDCs, and chronic obstructive sialadenitis was seen in 90.2% of cases. No cysts showed adenomatous ductal proliferations or true papillary structures with fibrovascular cores, although 41.2% exhibited reactive undulation of cyst lining. Thirty-nine 'papillary oncocytic cystadenoma-like' SDCs (22.0%) demonstrated complete oncocytic metaplasia and marked undulation. An additional seven such cysts (4.0%) had a 'Warthin tumor-like' lymphoplasmacytic infiltrate. Intraoral SDCs occur most commonly in the sixth decade of life in locations distinct from extravasation mucoceles, likely secondary to intraluminal obstruction. SDCs show diverse histopathology and certain phenotypic variants may be mistaken for papillary oncocytic cystadenoma or Warthin tumor.

Measure Guideline: Summary of Interior Ducts in New Construction, Including an Efficient, Affordable Method to Install Fur-Down Interior Ducts

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

Beal, D.; McIlvaine , J.; Fonorow, K.

2011-11-01

This document illustrates guidelines for the efficient installation of interior duct systems in new housing, including the fur-up chase method, the fur-down chase method, and interior ducts positioned in sealed attics or sealed crawl spaces. This document illustrates guidelines for the efficient installation of interior duct systems in new housing. Interior ducts result from bringing the duct work inside a home's thermal and air barrier. Architects, designers, builders, and new home buyers should thoroughly investigate any opportunity for energy savings that is as easy to implement during construction, such as the opportunity to construct interior duct work. In addition tomore » enhanced energy efficiency, interior ductwork results in other important advantages, such as improved indoor air quality, increased system durability and increased homeowner comfort. While the advantages of well-designed and constructed interior duct systems are recognized, the implementation of this approach has not gained a significant market acceptance. This guideline describes a variety of methods to create interior ducts including the fur-up chase method, the fur-down chase method, and interior ducts positioned in sealed attics or sealed crawl spaces. As communication of the intent of an interior duct system, and collaboration on its construction are paramount to success, this guideline details the critical design, planning, construction, inspection, and verification steps that must be taken. Involved in this process are individuals from the design team; sales/marketing team; and mechanical, insulation, plumbing, electrical, framing, drywall and solar contractors.« less

Pancreatic acinar cell carcinoma extending into the common bile and main pancreatic ducts.

PubMed

Yamaguchi, Rin; Okabe, Yoshinobu; Jimi, Atsuo; Shiota, Koji; Kodama, Takahito; Naito, Yoshiki; Yasunaga, Masafumi; Kinoshita, Hisafumi; Kojiro, Masamichi

2006-10-01

Acinar cell carcinoma (ACC) of the pancreas is relatively rare, accounting for only approximately 1% of all exocrine pancreatic tumors. A 69-year-old man was found to have a mass lesion measuring approximately 4 cm in diameter in the pancreatic head on ultrasound, abdominal dynamic CT, and percutaneous transhepatic cholangiography. Magnetic resonance cholangiopancreatography showed defect of the lower common bile duct (CBD) due to obstruction by the tumor cast. Histopathologically, the pancreatic head tumor invaded the main pancreatic duct (MPD) and CBD with extension into the CBD in a form of tumor cast. The tumor cells consisted of a solid proliferation with abundant eosinophilic cytoplasm and round nuclei in an acinar and trabecular fashion. A 55-year-old man with upper abdominal pain and nausea, had a cystic lesion approximately 3 cm in size in the pancreatic tail on CT. Histopathologically, the tumor was encapsulated by fibrous capsule and had extensive central necrosis with solid areas in the tumor periphery, and invaded with extension into the MPD in a form of tumor cast. The tumor cells resembled acinar cells in solid growths. Two resected cases of ACC with unusual tumor extension into the CBD and the MPD, respectively, are reported.

Convolution seal for transition duct in turbine system

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

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston

2015-05-26

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface feature for interfacing with an adjacent transition duct. The turbine system further includes a convolution seal contacting the interface feature to provide a seal between the interface feature andmore » the adjacent transition duct.« less

Obstructive Jaundice as an Uncommon Manifestation of Metastatic Breast Cancer.

PubMed

Budimir, Ivan; Sabol Pusic, Mateja; Nikolic, Marko; Dorosulic, Zdravko; Ljubicic, Neven; Stajduhar, Emil; Mise, Ivana; Vazdar, Ljubica; Sarcevic, Bozena

2015-02-01

Invasive ductal carcinoma is the most common type of breast cancer and accounts for about 70-85% of all invasive breast carcinomas. It primarily metastasizes to the bone, lungs, regional lymph nodes, liver and brain. Most of breast cancer recurrence occurs within the first 5 years of diagnosis, particularly for ER negative disease. Gastrointestinal tract involvement is very rare and is detected in only 10% of all the cases, and it usually derives from lobular breast cancer rather than the much more common cell type of ductal breast cancer. Early diagnosis is very important because it enables prompt and adequate choice of treatment and improves patient's long-term prognosis. In this report we describe an unusual case of obstructive jaundice caused by metastases from invasive ductal breast cancer to the lymph nodes of the hepatoduodenal ligament with extramural compression of the distal common bile duct and tumor invasion to the lumen of the duct. Our goal is to emphasize possible diagnostic pitfalls and increase the clinical awareness and the importance of intensive follow-up in patients with breast cancer, even years after the initial diagnosis.

Financial Aspects of Bile Duct Injuries.

PubMed

Palaz Alı, Ozgkıour; Ibis, Abdil Cem; Gurtekin, Basak

2017-11-04

BACKGROUND Major bile duct injury is the most worrisome complication of cholecystectomy. There is no detailed data about the incidence or treatment-related costs of bile duct injuries in Turkey. We aimed to determine prevalence and therapeutic costs of patients with major biliary duct injuries managed in our department, and further estimate a projection of these parameters at the national level. MATERIAL AND METHODS All patients admitted due to bile duct injury during cholecystectomy from 2011 to 2014 were included. Healthcare costs were calculated by summing of their all treatment-related costs in Istanbul Medical Faculty. We collected 2014-2015 data on number of patients diagnosed with cholecystitis in Turkey, the number of cholecystectomies, and the number of the interventions performed following these initial surgeries, which were obtained from the Turkish Social Security Institution. RESULTS Forty-nine patients were enrolled and bilioenteric diversion was performed in 39 patients: 20.4% of patients had Bismuth II, 38.8% had Bismuth III, and 40.8% had Bismuth IV biliary stricture. Comparison of stricture types with total costs, days of hospitalization, and outpatient clinic costs revealed significant differences. Mean total cost of corrective surgeries was 9199 TRY. We estimated that 1.5% to 2.4% of patients who underwent cholecystectomy in Turkey have bile duct injury (including 0.3% with major bile duct injury). CONCLUSIONS New preventive strategies should be used to avoid bile duct injuries, which have a huge financial impact on the national economy.

Duct Leakage Repeatability Testing

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

Walker, Iain; Sherman, Max

2014-08-01

The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques for duct leakage using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards. The three duct leak measurement methods assessed in this report are the twomore » duct pressurization methods that are commonly used by many practitioners and the DeltaQ technique. These are methods B, C and A, respectively of the ASTM E1554 standard. Although it would be useful to evaluate other duct leak test methods, this study focused on those test methods that are commonly used and are required in various test standards, such as BPI (2010), RESNET (2014), ASHRAE 62.2 (2013), California Title 24 (CEC 2012), DOE Weatherization and many other energy efficiency programs.« less

Articulated transition duct in turbomachine

DOEpatents

Flanagan, James Scott; McMahan, Kevin Weston; LeBegue, Jeffrey Scott; Pentecost, Ronnie Ray

2014-04-29

Turbine systems are provided. A turbine system includes a transition duct comprising an inlet, an outlet, and a duct passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The duct passage includes an upstream portion and a downstream portion. The upstream portion extends from the inlet between an inlet end and an aft end. The downstream portion extends from the outlet between an outlet end and a head end. The turbine system further includes a joint coupling the aft end of the upstream portion and the head end of the downstream portion together. The joint is configured to allow movement of the upstream portion and the downstream portion relative to each other about or along at least one axis.

Fan/Ram Duct Program

DTIC Science & Technology

1973-10-01

turbofan engine shutoff scheme, the ram duct flow conditions, and the Ian duct shutoff vane area transi- tion schedule. This loss will be...airflow. The performance of the turbofan is neglected until the main engine burner is ignited. At that time it is assumed that the turbo - fan...B. Transient Operation . . .. TRANSIENT TRANSITION TEST CASES A. Turbofan to Ramjet B. Ramjet to Turbo fan CONCLUSIONS AND RECOMMENDATIONS

Sound radiation from a flanged inclined duct.

PubMed

McAlpine, Alan; Daymond-King, Alex P; Kempton, Andrew J

2012-12-01

A simple method to calculate sound radiation from a flanged inclined duct is presented. An inclined annular duct is terminated by a rigid vertical plane. The duct termination is representative of a scarfed exit. The concept of a scarfed duct has been examined in turbofan aero-engines as a means to, potentially, shield a portion of the radiated sound from being transmitted directly to the ground. The sound field inside the annular duct is expressed in terms of spinning modes. Exterior to the duct, the radiated sound field owing to each mode can be expressed in terms of its directivity pattern, which is found by evaluating an appropriate form of Rayleigh's integral. The asymmetry is shown to affect the amplitude of the principal lobe of the directivity pattern, and to alter the proportion of the sound power radiated up or down. The methodology detailed in this article provides a simple engineering approach to investigate the sound radiation for a three-dimensional problem.

The acoustics of ducted propellers

NASA Astrophysics Data System (ADS)

Ali, Sherif F.

The return of the propeller to the long haul commercial service may be rapidly approaching in the form of advanced "prop fans". It is believed that the advanced turboprop will considerably reduce the operational cost. However, such aircraft will come into general use only if their noise levels meet the standards of community acceptability currently applied to existing aircraft. In this work a time-marching boundary-element technique is developed, and used to study the acoustics of ducted propeller. The numerical technique is developed in this work eliminated the inherent instability suffered by conventional approaches. The methodology is validated against other numerical and analytical results. The results show excellent agreement with the analytical solution and show no indication of unstable behavior. For the ducted propeller problem, the propeller is modeled by a rotating source-sink pairs, and the duct is modeled by rigid annular body of elliptical cross-section. Using the model and the developed technique, the effect of different parameters on the acoustic field is predicted and analyzed. This includes the effect of duct length, propeller axial location, and source Mach number. The results of this study show that installing a short duct around the propeller can reduce the noise that reaches an observer on a side line.

Laparoscopic hemi-hysterectomy in treatment of a didelphic uterus with a hypoplastic cervix and obstructed hemi-vagina.

PubMed

Boudhraa, K; Barbarino, A; Gara, Mohamed Faouzi

2008-11-01

Maldevelopment of the Müllerian duct system may result in various urogenital anomalies including didelphic uterus with a hypoplastic cervix and obstructed hemi-vagina. We report a patient with this anomaly who was treated by laparoscopic hemi-hysterectomy and hysteroscopic resection of hemi-vagina. A 16-year-old patient who had complained of vaginal pus-like discharge on and off for 1 year was diagnosed by MRI to have a double uterus with obstructed right hemi-vagina and ipsilateral renal agenesis. After hysteroscopic identification of hypoplasia of the right uterine cervix, laparoscopic resection of the right uterus and right fallopian tube and hysteroscopic assisted resection of the vaginal septa were performed successfully. We think that combined laparoscopy and hysteroscopy may be an effective alternative in the management and diagnosis of Mullerian anomalies.

Propagation and radiation of sound from flanged circular ducts with circumferentially varying wall admittances. I Semi-infinite ducts. II - Finite ducts with sources

NASA Technical Reports Server (NTRS)

Fuller, C. R.

1984-01-01

Sound propagation in infinite, semiinfinite, and finite circular ducts with circumferentially varying wall admittances is investigated analytically. The infinite case is considered, and an example demonstrates the effects of wall-admittance distribution on dispersion characteristics and mode shapes. An exact solution is obtained for the semiinfinite case, a circular duct with a flanged opening: sidelobe suppression and circumferential-mode energy scattering leading to radiated-field asymmetry are found. A finite duct system with specified hard-walled pressure sources is examined in detail, evaluating reflection coefficients, transmission losses, and radiated-field directivity. Graphs and diagrams are provided, and the implications of the results obtained for the design of aircraft-turbofan inlet liners are discussed.

Compact Buried Ducts in a Hot-Humid Climate House

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

Mallay, Dave

2016-01-07

"9A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval. The primary research question with buried ducts is potential condensation at the outer jacket of the duct insulation in humid climates during the cooling season. Current best practices for buried ducts rely onmore » encapsulating the insulated ducts with closed-cell spray polyurethane foam insulation to control condensation and improve air sealing. The encapsulated buried duct concept has been analyzed and shown to be effective in hot-humid climates. The purpose of this project is to develop an alternative buried duct system that performs effectively as ducts in conditioned space - durable, energy efficient, and cost-effective - in a hot-humid climate (IECC warm-humid climate zone 3A) with three goals that distinguish this project: 1) Evaluation of design criteria for buried ducts that use common materials and do not rely on encapsulation using spray foam or disrupt traditional work sequences; 2) Establishing design criteria for compact ducts and incorporate those with the buried duct criteria to further reduce energy losses and control installed costs; 3) Developing HVAC design guidance for performing accurate heating and cooling load calculations for compact buried ducts.« less

Bile duct adenoma and von Meyenburg complex-like duct arising in hepatitis and cirrhosis: pathogenesis and histological characteristics.

PubMed

Aishima, Shinichi; Tanaka, Yuki; Kubo, Yuichiro; Shirabe, Ken; Maehara, Yoshihiko; Oda, Yoshinao

2014-11-01

Morphologic features and neoplastic potentials of bile duct adenoma (BDA) and von Meyenburg complex (VMC)-like duct arising in chronic liver disease were unknown. Thirty-five BDAs and 12 VMC-like duct lesions were observed in 39 cases with chronic liver disease. BDAs were divided into the EMA-cytoplasmic type (n = 14) and EMA-luminal type (n = 21). EMA-cytoplasmic BDA composed of a proliferation of cuboidal to low-columnar cells forming an open lumen with NCAM(+)/MUC6(-), resembling an interlobular bile duct. EMA-luminal BDA showed uniform cuboidal cells with narrow lumen, and NCAM(++)/MUC6(++), resembling a ductular reaction. VMC-like duct showed positive MUC1 expression and negative MUC6. The expression of S100P, glucose transporter-1 (GLUT-1) and insulin-like growth factor II mRNA-binding protein 3 (IMP-3) were not detected in three lesions. p16 expression was higher than those of the ductular reaction, and the Ki67 and p53 indexes were very low (<1.0%). Large-sized EMA-luminal BDA shows sclerotic stroma. We classified small nodular lesions of ductal or ductular cells in chronic hepatitis and cirrhosis into the following groups: BDA, interlobular bile duct type; BDA, ductular/peribiliary gland type; and VMC-like duct. They may be reactive proliferation rather than neoplastic lesions. © 2014 Japanese Society of Pathology and Wiley Publishing Asia Pty Ltd.

Cystic Duct Closure by Sealing With Bipolar Electrocoagulation

PubMed Central

Damgaard, B.; Jorgensen, L. N.; Larsen, S. S.; Kristiansen, V. B.

2010-01-01

Background: Cystic duct leakage after cholecystectomy is not uncommon and is a potentially serious complication. The aim of this study was to assess a bipolar sealing system (LigaSure®) for closure of the cystic duct. Methods: The records from consecutive laparoscopic cholecystectomies performed in 2 hospitals with closure of the cystic duct with LigaSure after informed consent were recorded and complications and morbidity registered. The records were compared with those of patients undergoing laparoscopic cholecystectomy with closure of the cystic duct with clips during the same period. Results: During the study period, 218 laparoscopic cholecystectomies were performed; 102 of these were performed with the LigaSure. One patient was excluded due to violation of the protocol. We experienced no cases of cystic duct leakage, but in one patient, bile leakage from the gallbladder bed was observed probably due to a small aberrant duct. Conclusion: The LigaSure system was safe and effective for closure and division of the cystic duct in laparoscopic cholecystectomy. PMID:20412641

Acoustic propagation in curved ducts with extended reacting wall treatment

NASA Technical Reports Server (NTRS)

Baumeister, Kenneth J.

1989-01-01

A finite-element Galerkin formulation was employed to study the attenuation of acoustic waves propagating in two-dimensional S-curved ducts with absorbing walls without a mean flow. The reflection and transmission at the entrance and the exit of a curved duct were determined by coupling the finite-element solutions in the curved duct to the eigenfunctions of an infinite, uniform, hard wall duct. In the frequency range where the duct height and acoustic wave length are nearly equal, the effects of duct length, curvature (duct offset) and absorber thickness were examined. For a given offset in the curved duct, the length of the S-duct was found to significantly affect both the absorptive and reflective characteristics of the duct. A means of reducing the number of elements in the absorber region was also presented. In addition, for a curved duct, power attenuation contours were examined to determine conditions for maximum acoustic power absorption. Again, wall curvature was found to significantly effect the optimization process.

Reversible surgical model of biliary inflammation and obstructive jaundice in mice.

PubMed

Kirkland, Jacob G; Godfrey, Cody B; Garrett, Ryan; Kakar, Sanjay; Yeh, Benjamin M; Corvera, Carlos U

2010-12-01

Common bile duct (CBD) ligation is used in animal models to induce biliary inflammation, fibrosis, and cholestatic liver injury, but results in a high early postoperative mortality rate, probably from traumatic pancreatitis. We modified the CBD ligation model in mice by placing a small metal clip across the lower end of the CBD. To reverse biliary obstruction, a suture was incorporated within the clip during its placement. The suture and clip were removed on postoperative d 5 or 10 for biliary decompression. After 5 d of biliary obstruction, the gallbladder showed an 8-fold increase in wall thickness and a 17-fold increase in tissue myeloperoxidase activity. Markedly elevated serum levels of alkaline phosphatase and bilirubin indicated injury to the biliary epithelium and hepatocytes. Early postoperative (d 0-2) survival was 100% and later (d 3-5) survival was 85% (n=54 mice). We successfully reversed biliary obstruction in 20 mice (37%). Overall survival after reversal was 70%. In surviving mice, biliary decompression was complete, inflammation was reduced, and jaundice resolved. Histologic features confirmed reduced epithelial damage, edema, and neutrophil infiltration. Our technique minimized postoperative death, maintained an effective inflammatory response, and was easily reversible without requiring repeat laparotomy. This reversible model can be used to further define molecular mechanisms of biliary inflammation, fibrosis, and liver injury in genetically altered mice. Copyright © 2010. Published by Elsevier Inc.

Transition duct assembly with modified trailing edge in turbine system

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

McMahan, Kevin Weston; Schott, Carl Gerard; Ingram, Clint Luigie

2016-10-04

Transition duct assemblies for turbine systems and turbomachines are provided. In one embodiment, a transition duct assembly includes a plurality of transition ducts disposed in a generally annular array and comprising a first transition duct and a second transition duct. Each of the plurality of transition ducts includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of each transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct assembly further includes anmore » aerodynamic structure defined by the passages of the first transition duct and the second transition duct. The aerodynamic structure includes a pressure side, a suction side, and a trailing edge, the trailing edge having a modified aerodynamic contour.« less

Cholestasis‐induced adaptive remodeling of interlobular bile ducts

PubMed Central

Damle‐Vartak, Amruta; Richter, Beate; Dirsch, Olaf; Dahmen, Uta; Hammad, Seddik

2016-01-01

Cholestasis is a common complication in liver diseases that triggers a proliferative response of the biliary tree. Bile duct ligation (BDL) is a frequently used model of cholestasis in rodents. To determine which changes occur in the three‐dimensional (3D) architecture of the interlobular bile duct during cholestasis, we used 3D confocal imaging, surface reconstructions, and automated image quantification covering a period up to 28 days after BDL. We show a highly reproducible sequence of interlobular duct remodeling, where cholangiocyte proliferation initially causes corrugation of the luminal duct surface, leading to an approximately five‐fold increase in surface area. This is analogous to the function of villi in the intestine or sulci in the brain, where an expansion of area is achieved within a restricted volume. The increase in surface area is further enhanced by duct branching, branch elongation, and loop formation through self‐joining, whereby an initially relatively sparse mesh surrounding the portal vein becomes five‐fold denser through elongation, corrugation, and ramification. The number of connections between the bile duct and the lobular bile canalicular network by the canals of Hering decreases proportionally to the increase in bile duct length, suggesting that no novel connections are established. The diameter of the interlobular bile duct remains constant after BDL, a response that is qualitatively distinct from that of large bile ducts, which tend to enlarge their diameters. Therefore, volume enhancement is only due to net elongation of the ducts. Because curvature and tortuosity of the bile duct are unaltered, this enlargement of the biliary tree is caused by branching and not by convolution. Conclusion: BDL causes adaptive remodeling that aims at optimizing the intraluminal surface area by way of corrugation and branching. (Hepatology 2016;63:951–964) PMID:26610202

Design and performance of duct acoustic treatment

NASA Technical Reports Server (NTRS)

Motsinger, R. E.; Kraft, R. E.

1991-01-01

The procedure for designing acoustic treatment panels used to line the walls of aircraft engine ducts and for estimating the resulting suppression of turbofan engine duct noise is discussed. This procedure is intended to be used for estimating noise suppression of existing designs or for designing new acoustic treatment panels and duct configurations to achieve desired suppression levels.

Turbofan aft duct suppressor study program listing and user's guide

NASA Technical Reports Server (NTRS)

Joshi, M. C.; Kraft, R. E.

1983-01-01

A description of the structure of the Annular Flow Duct Program (AFDP) for the calculation of acoustic suppression due to treatment in a finite length annular duct carrying sheared flow is presented. Although most appropriate for engine exhaust ducts, this program can be used to study sound propagation in any duct that maintains annular geometry over a considerable length of the duct. The program is based on the modal analysis of sound propagation in ducts with axial segments of different wall impedances. For specified duct geometry, wall impedance, flow and acoustic conditions in the duct (including mode amplitude distribution of the source) and duct termination reflection characteristics, the program calculates the suppression due to the treatment in the duct. The presence of forward and backward traveling modes in the duct due to the reflection and redistribution of modes at segment interfaces and duct end terminations are taken into account in the calculations. The effects of thin wall boundary layers (with a linear or mean flow velocity profile) on the acoustic propagation are also included in the program. A functional description of the major subroutines is included and a sample run is provided with an explanation of the output.

MRI ductography of contrast agent distribution and leakage in normal mouse mammary ducts and ducts with in situ cancer.

PubMed

Markiewicz, Erica; Fan, Xiaobing; Mustafi, Devkumar; Zamora, Marta; Conzen, Suzanne D; Karczmar, Gregory S

2017-07-01

High resolution 3D MRI was used to study contrast agent distribution and leakage in normal mouse mammary glands and glands containing in situ cancer after intra-ductal injection. Five female FVB/N mice (~19weeks old) with no detectable mammary cancer and eight C3(1) SV40 Tag virgin female mice (~15weeks old) with extensive in situ cancer were studied. A 34G, 45° tip Hamilton needle with a 25μL Hamilton syringe was inserted into the tip of the nipple and approximately 15μL of a Gadodiamide was injected slowly over 1min into the nipple and throughout the duct on one side of the inguinal gland. Following injection, the mouse was placed in a 9.4T MRI scanner, and a series of high resolution 3D T1-weighted images was acquired with a temporal resolution of 9.1min to follow contrast agent leakage from the ducts. The first image was acquired at about 12min after injection. Ductal enhancement regions detected in images acquired between 12 and 21min after contrast agent injection was five times smaller in SV40 mouse mammary ducts (p<0.001) than in non-cancerous FVB/N mouse mammary ducts, perhaps due to rapid washout of contrast agent from the SV40 ducts. The contrast agent washout rate measured between 12min and 90min after injection was ~20% faster (p<0.004) in SV40 mammary ducts than in FVB/N mammary ducts. These results may be due to higher permeability of the SV40 ducts, likely due to the presence of in situ cancers. Therefore, increased permeability of ducts may indicate early stage breast cancers. Copyright © 2017 Elsevier Inc. All rights reserved.

Generator stator core vent duct spacer posts

DOEpatents

Griffith, John Wesley; Tong, Wei

2003-06-24

Generator stator cores are constructed by stacking many layers of magnetic laminations. Ventilation ducts may be inserted between these layers by inserting spacers into the core stack. The ventilation ducts allow for the passage of cooling gas through the core during operation. The spacers or spacer posts are positioned between groups of the magnetic laminations to define the ventilation ducts. The spacer posts are secured with longitudinal axes thereof substantially parallel to the core axis. With this structure, core tightness can be assured while maximizing ventilation duct cross section for gas flow and minimizing magnetic loss in the spacers.

[Stenon or Stensen duct. How sholud we call the secretory duct of the parotid gland? Brief biography of its discoverer].

PubMed

Morais Pérez, D

2004-01-01

The duct of the parotid gland had been indiscriminately named Stenon's duct or Stensen's duct. In order to establish its origin we carried out a biographic search and a brief revision of the life of the great anatomist, geologist, palaeontologist, bishop and finally Saint Nicolaus Stensen.

Transition duct with divided upstream and downstream portions

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

McMahan, Kevin Weston; LeBegue, Jeffrey Scott; Maldonado, Jaime Javier

2015-07-14

Turbine systems are provided. In one embodiment, a turbine system includes a transition duct comprising an inlet, an outlet, and a duct passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The duct passage includes an upstream portion extending from the inlet and a downstream portion extending from the outlet. The turbine system further includes a rib extending from an outer surface of the duct passage, the rib dividing themore » upstream portion and the downstream portion.« less

Flow control in a diffusing S-Duct

NASA Technical Reports Server (NTRS)

Vakili, A. D.; Wu, J. M.; Liver, P.; Bhat, M. K.

1985-01-01

Accurate measurements have been made of secondary flow in a 1.51 area ratio diffusing 30 deg - 30 deg S-Duct with circulair cross section. Turbulent flow was entering the duct at Mach number of 0.6, the boundary layer thickness at the duct entrance was ten percent of the duct inlet diameter. Through measurements made, local flow velocity vector as well as static and total pressures mapping of the flow at several stations were obtained. Strong secondary flow was measured in the first bend which continued into the second bend with new vorticity produced in there in the opposite direction. Surface oil flow visualization and wall pressures indicated a region of separated flow starting at theta approximately equal to 22 deg on the inside of the first bend up to theta approximately equal to 44 deg on the outside of the second bend. The flow separated in 'cyclone' form and never reattached in the duct. As a result of the secondary flow and the flow separation, significant total pressure distortion was observed at the exit of the duct. Using flow control devices the separation was eliminated while the exit distortion was improved.

[Endoscopic manometry in the common bile duct].

PubMed

Brandstätter, G; Kratochvil, P; Stupnicki, T; Zenker, G; Justich, E; Resch, M

1982-09-17

Reproducible results were obtained by endoscopic transpapillary pressure measurements with the help of a constantly perfused catheter. Manometric measurements were performed in 51 patients without any premedication. 14 patients with a normal biliary system were compared with 17 patients after cholecystectomy, 14 patients with stones in the common bile duct and 6 patients after papillotomy. Although there were significant differences in the diameter of the common bile duct in the four groups, only the papillotomized patients demonstrated a distinct change of the pressure in the bile duct. In these patients almost no pressure gradient existed between the biliary ducts and the duodenum. On the other hand, there was an increase in intraluminal pressure in the 2 patients with papillary stenosis. Endoscopic manometric measurements in the common bile duct are indicated to obtain reliable data on stenosis of the papilla duodeni, insufficient papillotomy or recurrent stenosis.

Preventive saline irrigation of the bile duct after the endoscopic removal of common bile duct stones.

PubMed

Jang, Sang Eon; Ahn, Dong-Won; Lee, Sang Hyub; Lee, Ban Seok; Jeong, Ji Bong; Hwang, Jin-Hyeok; Ryu, Ji Kon; Kim, Yong-Tae; Lee, Kyoung Ho; Kim, Young Hoon

2013-08-01

Small stone fragments after an endoscopic stone extraction for choledocholithiasis may act as the nidus for recurrent choledocholithiasis. Therefore, efforts to eliminate the nidus might reduce the recurrence of choledocholithiasis and cholangitis related to choledocholithiasis. The purpose of this study was to determine whether an additional preventive saline irrigation of the bile duct after the endoscopic removal of common bile duct stones would decrease residual stones and the recurrence of cholangitis. A retrospective analysis was performed for the consecutively collected data about the patients who underwent the complete endoscopic treatment for common bile duct stone. Among 99 patients, 45 patients underwent saline irrigation. Residual stones were detected in 18 patients (18.2 %). The incidences of residual stones were 8.9 % (4 of 45 patients) in the irrigation group and 25.9 % (14 of 54 patients) in the non-irrigation group (P = 0.037). In multivariate analysis, preventive saline irrigation was found to be the only significant factor for the decrease of residual stones (HR = 0.258, P = 0.039). When analyzing the occurrence of recurrent cholangitis and the procedure related to complications, there were no significant differences according to the performance of preventive saline irrigation of the bile duct. Preventive saline irrigation could reduce the residual common bile duct stones without complications.

Traumatic resin ducts as indicators of bark beetle outbreaks

Treesearch

R. Justin DeRose; Matthew F. Bekker; James N. Long

2017-01-01

The formation of traumatic resin ducts (TRDs) represents an important induced defense in woody plants that enhances oleoresin production and flow in response to environmental perturbations. In some genera (Pinus), resin ducts are copious and conspicuous; however, in others (Picea), resin ducts are relatively rare. The occurrence and strength of resin ducts, in...

Coupled parametric design of flow control and duct shape

NASA Technical Reports Server (NTRS)

Florea, Razvan (Inventor); Bertuccioli, Luca (Inventor)

2009-01-01

A method for designing gas turbine engine components using a coupled parametric analysis of part geometry and flow control is disclosed. Included are the steps of parametrically defining the geometry of the duct wall shape, parametrically defining one or more flow control actuators in the duct wall, measuring a plurality of performance parameters or metrics (e.g., flow characteristics) of the duct and comparing the results of the measurement with desired or target parameters, and selecting the optimal duct geometry and flow control for at least a portion of the duct, the selection process including evaluating the plurality of performance metrics in a pareto analysis. The use of this method in the design of inter-turbine transition ducts, serpentine ducts, inlets, diffusers, and similar components provides a design which reduces pressure losses and flow profile distortions.

Meta-analysis of Duct-to-duct versus Roux-en-Y biliary reconstruction following liver transplantation for primary sclerosing cholangitis.

PubMed

Pandanaboyana, Sanjay; Bell, Richard; Bartlett, Adam J; McCall, John; Hidalgo, Ernest

2015-04-01

This meta-analysis aimed to compare outcomes following bile duct reconstruction in patients with primary sclerosing cholangitis (PSC) undergoing liver transplantation depending on whether duct-to-duct or Roux-en-Y anastomosis was utilized. An electronic search was performed of the MEDLINE, EMBASE, PubMed databases using both subject headings (MeSH) and truncated word searches. Pooled risk ratios and mean difference were calculated using the fixed-effects and random-effects models for meta-analysis. Ten studies including 910 patients met the inclusion criteria. There was no difference in the overall incidence of biliary strictures between the two groups [odds ratio (OR) 1.06 (0.68, 1.66); (P = 0.80)]. The anastomotic stricture rate was similar, [OR 1.18 (0.56, 2.50); (P = 0.67)]. Ascending cholangitis was higher in the Roux-en-Y group [OR 2.91 (1.17, 7.23); (P = 0.02)]. Anastomotic bile leak rates, graft survival, PSC recurrence and number of patients diagnosed with cholangiocarcinoma following transplantation were comparable between both groups. Duct-to-duct and Roux-en-Y reconstruction had comparable outcomes. Both techniques are associated with similar incidence of biliary stricture. The bilioenteric reconstruction was associated with a higher risk of cholangitis. The incidence of de novo cholangiocarcinoma was similar in both groups. Duct-to-duct reconstruction should be considered when feasible in patients with PSC. © 2015 Steunstichting ESOT.

Decline of the performance of a portable axial-flow fan due to the friction and duct bending loss of a connected flexible duct.

PubMed

Ojima, Jun

2017-03-28

In a job site, a portable fan is often used to ventilate a confined space. When a portable fan is applied to such a space, the actual ventilation flow rate must be accurately estimated in advance because the safety level of contaminant and oxygen concentrations in the space will determine the ventilation requirements. When a portable fan is used with a flexible duct, the actual flow rate of the fan decreases due to the friction and duct bending loss of the duct. Intending to show the decline of a fan performance, the author conducted laboratory experiments and reported the quantitative effect of the friction and duct bending loss of a flexible duct to the flow rate of a portable fan. Four commercial portable fans of different specifications were procured for the experiments, and the decline of the performance of each portable fan due to the friction loss etc. of a connected flexible duct was investigated by measuring actual flow rate. The flow rate showed an obvious decrease from the rated flow rate when a flexible duct was connected. Connection of a straight polyester flexible duct and a straight aluminum flexible duct reduced the flow rates to 81.2 - 52.9% and less than 50%, respectively. The flow rate decreased with an increase of the bend angle of the flexible duct. It is recommended that flow rate check of a portable fan should be diligently carried out in every job site.

[Iatrogenic bile duct injuries during the process of laparoscopic cholecystectomy].

PubMed

Qian, G; Wu, M; Zhang, Y

1995-11-01

Twelve patients with iatrogenic bile duct injuries occurred during laparoscopic cholecystectomy (LC) were treated from June 1992 to May 1994. All the patients underwent re-operation and were cured. The causes and characteristics of the injuries were: (1) perforation of the common hepatic or common bile duct caused by dissecting hook (3 cases); (2) necrosis and perforation of the common hepatic duct due to diathermic injury (1 case); (3) clamping of the common hepatic duct by Ti clip (1 case); (4) secondary high bile duct stricture following a failed end-to-end anastomosis or hepatico-cholangio-jejunostomy of the amputated common hepatic duct (5 cases); (5) delayed high bile duct stricture (2 cases). It is emphasized that the severity of bile duct injuries by LC be should not overlooked, and more experience in this field be accumulated to avoid this serious complication.

Heterogeneity Between Ducts of the Same Nuclear Grade Involved by Duct Carcinoma In Situ (DCIS) of the Breast

PubMed Central

Miller, Naomi A.; Chapman, Judith-Anne W.; Qian, Jin; Christens-Barry, William A.; Fu, Yuejiao; Yuan, Yan; Lickley, H. Lavina A.; Axelrod, David E.

2010-01-01

Purpose Nuclear grade of breast DCIS is considered during patient management decision-making although it may have only a modest prognostic association with therapeutic outcome. We hypothesized that visual inspection may miss substantive differences in nuclei classified as having the same nuclear grade. To test this hypothesis, we measured subvisual nuclear features by quantitative image cytometry for nuclei with the same grade, and tested for statistical differences in these features. Experimental design and statistical analysis Thirty-nine nuclear digital image features of about 100 nuclei were measured in digital images of H&E stained slides of 81 breast biopsy specimens. One field with at least 5 ducts was evaluated for each patient. We compared features of nuclei with the same grade in multiple ducts of the same patient with ANOVA (or Welch test), and compared features of nuclei with the same grade in two ducts of different patients using 2-sided t-tests (P ≤ 0.05). Also, we compared image features for nuclei in patients with single grade to those with the same grade in patients with multiple grades using t-tests. Results Statistically significant differences were detected in nuclear features between ducts with the same nuclear grade, both in different ducts of the same patient, and between ducts in different patients with DCIS of more than one grade. Conclusion Nuclei in ducts visually described as having the same nuclear grade had significantly different subvisual digital image features. These subvisual differences may be considered additional manifestations of heterogeneity over and above differences that can be observed microscopically. This heterogeneity may explain the inconsistency of nuclear grading as a prognostic factor. PMID:20981137

Subsonic Flows through S-Ducts with Flow Control

NASA Astrophysics Data System (ADS)

Chen, Yi

An inlet duct of an aircraft connects the air intake mounted on the fuselage to the engine within the aircraft body. The ideal outflow quality of the duct is steady, uniform and of high total pressure. Recently compact S-shaped inlet ducts are drawing more attention in the design of UAVs with short propulsion system. Compact ducts usually involve strong streamwise adverse pressure gradient and transverse secondary flow, leading to large-scale harmful vortical structures in the outflow. To improve the outflow quality modern flow control techniques have to be applied. Before designing successful flow control methods a solid understanding of the baseline flow field with the duct is crucial. In this work the fundamental mechanism of how the three dimensional flow topology evolves when the relevant parameters such as the duct geometry and boundary layer thickness are varied, is studied carefully. Two distinct secondary-flow patterns are identified. For the first time the sensitivity of the flow topology to the inflow boundary layer thickness in long ducts is clearly addressed. The interaction between the transverse motion induced by the transverse pressure gradient and the streamwise separation is revealed as the crucial reason for the various flow patterns existing in short ducts. A non-symmetric flow pattern is identified for the first time in both experiments and simulations in short ducts in which the intensity of the streamwise separation and the transverse invasion are in the same order of magnitude. A theory of energy accumulation and solution bifurcation is used to give a reasonable explanation for this non-symmetry. After gaining the knowledge of where and how the harmful vortical structures are generated several flow control techniques are tested to achieve a better outflow quality. The analysis of the flow control cases also provides a deeper insight into the behavior of the three-dimensional flow within the ducts. The conventional separation control method

Predicting vibrational failure of flexible ducting

NASA Technical Reports Server (NTRS)

Henry, R. H.

1971-01-01

Technique applies to liquid or gas transfer through flexible ducting and proves valuable in high velocity fluid flow cases. Fluid mechanism responsible for free bellows vibrational excitation also causes flexible hose oscillation. Static pressure stress influences flexible ducting fatigue life and is considered separately.

Bicanalicular Silicone Stents in Endonasal Dacryocystorhinostomy: Results of a Randomized Clinical Trial.

PubMed

Fayers, Tessa; Dolman, Peter J

2016-10-01

To assess whether the use of silicone lacrimal stents affects the long-term success of endonasal dacryocystorhinostomy (EN-DCR). Prospective, randomized, controlled, interventional trial. The subjects were adult patients older than 16 years undergoing primary EN-DCR for nasolacrimal duct obstruction who gave fully informed consent and who had no lid malpositions or canalicular pathology. In cases with bilateral surgery, only the right eyes were studied. Participants were randomized to receive stents (control group) or not (study group). Standardized nonendoscopic EN-DCR was performed by the senior author in all cases. When the ostium was completed, the randomization code was revealed as to whether a lacrimal stent was placed or not. Follow-up assessments were made at 3, 6, 9, and 12 months. Stents were removed at 3 months. The primary end point was symptoms of epiphora at 12 months, reported to the surgical booking clerk as (a) resolved, (b) significantly improved, (c) partially improved, or (d) no change or worse. The secondary end point was anatomic patency based on nasolacrimal syringing and categorized as (a) fully patent, minimal, or no reflux; (b) >50% patent but some reflux; (c) some patency but >50% reflux; or (d) nonpatent, 100% reflux. Complete success was defined as having resolved or significantly improved symptoms of watering and minimal or no reflux on nasolacrimal syringing. Partial success was defined as symptoms partially improved with a combination of patency and reflux on syringing. Failure was categorized as no change or worse symptoms of watering and 50% to 100% reflux on syringing. A total of 300 patients completed 12 months of follow-up. A total of 152 patients received tubes, and 148 patients did not. Overall success both subjectively and objectively was 94.7% in the stented group and 87.8% in the nonstented group (P = 0.034, Pearson chi-square 1-tailed test). The most common complications of stents included canalicular cheese-wiring and

Parotid salivary duct stenosis following caudal maxillectomy.

PubMed

Mestrinho, Lisa A; Faísca, Pedro B; Niza, Maria M R E

2014-01-01

Parotid salivary duct dilation was diagnosed in a 9-year-old male dog. The dog had undergone caudal maxillectomy on the ipsilateral side 2-years prior to presentation. Treatment consisted of parotid salivary duct excision and superficial parotidectomy that lead to the resolution of clinical signs. Transient facial neuropraxia was observed immediately after surgery and resolved spontaneously after 2-weeks. Parotid salivary duct dilation should be considered as a chronic postoperative complication following caudal maxillectomy.

Flow duct for nuclear reactors

DOEpatents

Straalsund, Jerry L.

1978-01-01

Improved liquid sodium flow ducts for nuclear reactors are described wherein the improvement comprises varying the wall thickness of each of the walls of a polygonal tubular duct structure so that each of the walls is of reduced cross-section along the longitudinal center line and of a greater cross-section along wall junctions with the other walls to form the polygonal tubular configuration.

Bile duct epithelial tight junctions and barrier function

PubMed Central

Rao, R.K.; Samak, G.

2013-01-01

Bile ducts play a crucial role in the formation and secretion of bile as well as excretion of circulating xenobiotic substances. In addition to its secretory and excretory functions, bile duct epithelium plays an important role in the formation of a barrier to the diffusion of toxic substances from bile into the hepatic interstitial tissue. Disruption of barrier function and toxic injury to liver cells appear to be involved in the pathogenesis of a variety of liver diseases such as primary sclerosing cholangitis, primary biliary cirrhosis and cholangiocarcinoma. Although the investigations into understanding the structure and regulation of tight junctions in gut, renal and endothelial tissues have expanded rapidly, very little is known about the structure and regulation of tight junctions in the bile duct epithelium. In this article we summarize the current understanding of physiology and pathophysiology of bile duct epithelium, the structure and regulation of tight junctions in canaliculi and bile duct epithelia and different mechanisms involved in the regulation of disruption and protection of bile duct epithelial tight junctions. This article will make a case for the need of future investigations toward our understanding of molecular organization and regulation of canalicular and bile duct epithelial tight junctions. PMID:24665411

Analyses of radiation impedances of finite cylindrical ducts

NASA Astrophysics Data System (ADS)

Shao, W.; Mechefske, C. K.

2005-08-01

To aid in understanding the characteristics of acoustic radiation from finite cylindrical ducts with infinite flanges, mathematical expressions of generalized radiation impedances at the open ends have been developed. Newton's method is used to find the complex wavenumbers of radial modes for the absorption boundary condition. The self-radiation impedances and mutual impedances for some acoustic modes are calculated for the ducts with rigid and absorption walls. The results show that the acoustical conditions of the duct walls have a significant influence on the radiation impedance. The acoustical interaction between the two open ends of the ducts cannot be neglected, especially for plane waves. To increase the wall admittance will reduce this interference effect. This study creates the possibility for simulating the sound field inside finite ducts in future work.

Turbofan Duct Propagation Model

NASA Technical Reports Server (NTRS)

Lan, Justin H.; Posey, Joe W. (Technical Monitor)

2001-01-01

The CDUCT code utilizes a parabolic approximation to the convected Helmholtz equation in order to efficiently model acoustic propagation in acoustically treated, complex shaped ducts. The parabolic approximation solves one-way wave propagation with a marching method which neglects backwards reflected waves. The derivation of the parabolic approximation is presented. Several code validation cases are given. An acoustic lining design process for an example aft fan duct is discussed. It is noted that the method can efficiently model realistic three-dimension effects, acoustic lining, and flow within the computational capabilities of a typical computer workstation.

Rotating Rake Turbofan Duct Mode Measurement System

NASA Technical Reports Server (NTRS)

Sutliff, Daniel L.

2005-01-01

An experimental measurement system was developed and implemented by the NASA Glenn Research Center in the 1990s to measure turbofan duct acoustic modes. The system is a continuously rotating radial microphone rake that is inserted into the duct. This Rotating Rake provides a complete map of the acoustic duct modes present in a ducted fan and has been used on a variety of test articles: from a low-speed, concept test rig, to a full-scale production turbofan engine. The Rotating Rake has been critical in developing and evaluating a number of noise reduction concepts as well as providing experimental databases for verification of several aero-acoustic codes. More detailed derivation of the unique Rotating Rake equations are presented in the appendix.

Surgery or EUS-guided choledochoduodenostomy for malignant distal biliary obstruction after ERCP failure

PubMed Central

Artifon, Everson L.A.; Loureiro, Jarbas F.; Baron, Todd H.; Fernandes, Kaie; Kahaleh, Michel; Marson, Fernando P.

2015-01-01

Background and Objectives: Endoscopic retrograde cholangiopancreatography (ERCP) is the method of choice for drainage in patients with distal malignant biliary obstruction, but it fails in up to 10% of cases. Percutaneous transhepatic cholangiography (PTC) and surgical bypass are the traditional drainage alternatives. This study aimed to compare technical and clinical success, quality of life, and survival of surgical biliary bypass or hepaticojejunostomy (HJT) and endoscopic ultrasound (EUS)-guided choledochoduodenostomy (CDT) in patients with distal malignant bile duct obstruction and failed ERCP. Patients and Methods: A prospective, randomized trial was conducted. From March 2011 to September 2013, 32 patients with malignant distal biliary obstruction and failed ERCP were studied. The HJT group consisted of 15 patients and the CDT group consisted of 14 patients. Technical and clinical success, quality of life, and survival were assessed prospectively. Results: Technical success was 94% (15/16) in the HJT group and 88% (14/16) in the CDT group (P = 0.598). Clinical success occurred in 14 (93%) patients in the HJT group and in 10 (71%) patients in the CDT group (P = 0.169). During follow-up, a statistically significant difference was seen in mean functional capacity scores, physical health, pain, social functioning, and emotional and mental health aspects in both techniques (P < 0.05). The median survival time in both groups was the same (82 days). Conclusion: Data relating to technical and clinical success, quality of life, and survival were similar in patients who underwent HJT and CDT drainage after failed ERCP for malignant distal biliary obstruction. PMID:26374583

Glucagon-like peptide-2 protects impaired intestinal mucosal barriers in obstructive jaundice rats.

PubMed

Chen, Jun; Dong, Jia-Tian; Li, Xiao-Jing; Gu, Ye; Cheng, Zhi-Jian; Cai, Yuan-Kun

2015-01-14

To observe the protective effect of glucagon-like peptide-2 (GLP-2) on the intestinal barrier of rats with obstructive jaundice and determine the possible mechanisms of action involved in the protective effect. Thirty-six Sprague-Dawley rats were randomly divided into a sham operation group, an obstructive jaundice group, and a GLP-2 group; each group consisted of 12 rats. The GLP-2 group was treated with GLP-2 after the day of surgery, whereas the other two groups were treated with the same concentration of normal saline. Alanine aminotransferase (ALT), total bilirubin, and endotoxin levels were recorded at 1, 3, 7, 10 and 14 d. Furthermore, on the 14(th) day, body weight, the wet weight of the small intestine, pathological changes of the small intestine and the immunoglobulin A (IgA) expressed by plasma cells located in the small intestinal lamina propria were recorded for each group. In the rat model, jaundice was obvious, and the rats' activity decreased 4-6 d post bile duct ligation. Compared with the sham operation group, the obstructive jaundice group displayed increased yellow staining of abdominal visceral serosa, decreased small intestine wet weight, thinning of the intestinal muscle layer and villi, villous atrophy, uneven height, fusion, partial villous epithelial cell shedding, substantial inflammatory cell infiltration and significantly reduced IgA expression. However, no significant gross changes were noted between the GLP-2 and sham groups. With time, the levels of ALT, endotoxin and bilirubin in the GLP-2 group were significantly increased compared with the sham group (P < 0.01). The increasing levels of the aforementioned markers were more significant in the obstructive jaundice group than in the GLP-2 group (P < 0.01). GLP-2 reduces intestinal mucosal injuries in obstructive jaundice rats, which might be attributed to increased intestinal IgA and reduced bilirubin and endotoxin.

Albumin expression distinguishes bile duct adenomas from metastatic adenocarcinoma.

PubMed

Moy, Andrea P; Arora, Kshitij; Deshpande, Vikram

2016-09-01

Bile duct adenomas may be difficult to distinguish from metastatic carcinomas, particularly well-differentiated pancreatic ductal adenocarcinoma. Prior studies have evaluated the utility of various immunohistochemical markers, although these markers are notable for low sensitivity and/or specificity. The aim of this study was to investigate the utility of albumin and BRAFV600E expression in distinguishing between metastatic pancreatic adenocarcinoma and bile duct adenoma. We studied 26 bile duct adenomas, three bile duct hamartomas, and 158 pancreatic ductal adenocarcinomas. Branched-chain in-situ hybridization (bISH) for albumin was performed; bISH is based on the branched DNA technology, wherein signal amplification is achieved via a series of sequential steps. Additionally, BRAFV600E immunohistochemistry (IHC) was performed on a subset of cases. Twenty-three of 25 (92%) bile duct adenomas were positive for albumin; 18 (72%) showed diffuse staining, and five showed focal staining (20%), including two challenging examples. Two bile duct hamartomas also stained positively. All pancreatic adenocarcinomas were negative for albumin. Seven of 16 (44%) bile duct adenomas and five of 106 (5%) pancreatic ductal adenocarcinomas were positive for BRAFV600E by IHC. The sensitivity and specificity of expression of albumin, as detected by bISH, for distinguishing bile duct adenomas from metastatic pancreatic adenocarcinomas were 92% and 100%, respectively; the sensitivity and specificity of BRAFV600E IHC for distinguishing bile duct adenomas from metastatic pancreatic adenocarcinomas were 43.8% and 95.3%, respectively. Diagnostically challenging examples of bile duct adenoma may be distinguished from metastatic pancreatic adenocarcinoma by the use of albumin bISH. © 2016 John Wiley & Sons Ltd.

Magnetic resonance imaging in the pre-operative evaluation of obstructive epiphora: true-FISP and VIBE vs gadolinium.

PubMed

Somma, Francesco; d'Agostino, Vincenzo; Tortora, Fabio; Serra, Nicola; Sorrentino, Gerardo; Piscitelli, Valeria; Somma, Andrea; Gamerra, Mario

2017-02-01

To assess unenhanced magnetic resonance imaging (MRI) in the preoperative evaluation of obstructive epiphora in patients undergoing dacryocystorhinostomy (DCR) and in particular, to evaluate the efficacy of this technique in the detection of the exact level of obstruction occurring in the naso-lachrymal duct (NLD). The correct identification and characterization of the NLD and its obstructions lead to a more effective surgery, preventing recurrent dacryocystitis after the surgical treatment. From January 2009 to December 2014, 127 obstructive epiphoras were diagnosed and treated in 127 patients (35 M, 92 F; mean age 60.7 ± 7.48 years, range 42-75 years) with endoscopic DCR, in a IRB-approved protocol. To precisely define the morphology of the NLD and the site of obstruction, some of these patients (67/127) underwent unenhanced 1.5-T MR with TrueFISP and VIBE sequences, while the remaining (60/127) underwent Gadolinium-enhanced 1.5-T MR. Afterwards, surgery checked the real site of obstruction in both groups of patients (enhanced and unenhanced MR), with surgical outcomes matched with previous MR reports. In all cases, unenhanced MRI was able to detect the exact site of obstruction along the NLD, allowing a correct planning of surgical endoscopic procedures. On the contrary, enhanced MRI wrongly diagnosed six patients with proximal stenosis (6/60, 10.0%) as intermediate NLD obstruction. Unenhanced MRI was found to be more accurate than enhanced MRI with a statistical significant difference (p value = 0.0256) and obviously cheaper and easier to perform. All imaging reports were verified with surgery. The correct identification of the level of obstruction allowed successful surgery in around 73% (93/127) of patients, who had no recurrence during 6-month follow-up. In patients with epiphora, unenhanced MR showed to be highly reliable and even more effective than enhanced MR in the preoperative characterization of NLD stenosis, with no need of performing complex

Common Bile Duct Stricture After Laparoscopic Cholecystectomy: Case Report

PubMed

Zoričić, Ivan; Soldo, Ivo; Simović, Ivan; Sever, Marko; Bakula, Branko; Grbavac, Martin; Marušić, Marinko; Soldo, Anamaria

2017-03-01

Despite progress in laparoscopic surgery and increasing surgical experience, the incidence of bile duct injury during laparoscopic cholecystectomy fails to fall below 0.3%-0.6% and it is still higher than those recorded in the era of open cholecystectomy. Bile duct injuries belong to the most serious complications of abdominal surgery in general and often end up with liver transplantation as the only hope for cure. We present a case of a 78-year-old jaundiced male patient who sustained common hepatic duct injury during laparoscopic cholecystectomy eight months earlier. Exploratory laparotomy, ERCP and MRCP revealed a metal clip placed just below hepatic duct confluence and causing stricture of bile duct with dilatation of bile ducts proximal to the level of stenosis (Strasberg classification type E3 injury). Repair of the injury was performed by creating termino-lateral hepaticojejunostomy between the right and left hepatic ducts and retrocolic Roux en-Y jejunal limb. By presenting this case, we wish to emphasize the importance of timely conversion and execution of intraoperative cholangiography in all cases when identification of the structures of Calot’s triangle is not clear enough. Successful treatment of bile duct injury is only possible with joint approach of radiologist, gastroenterologist and experienced hepatobiliary surgeon.

Long duct nacelle aerodynamic development for DC-10 derivatives

NASA Technical Reports Server (NTRS)

Patel, S. P.; Donelson, J. E.

1980-01-01

The results are presented of a wind tunnel test utilizing a 4.7-percent-scale semispan model of the DC-10 in the Calspan 8-foot transonic wind tunnel. The effect of a revised long-duct nacelle shape on the channel velocities, the incremental drag relative to the baseline long-duct nacelle, and channel velocities for the baseline long-duct nacelle were determined and compared with data obtained at Ames. The baseline and the revised long-duct nacelles are representative of a CF6-50 mixed-flow configuration and were evaluated on a model of a proposed DC-10 stretched-fuselage configuration. The results showed that the revised long-duct nacelle has an appreciable effect on the inboard channel velocities, resulting in an increased channel Mach number. However, the pressure recovery on the nacelle afterbody was about the same for both nacelles. The lift curves for both long-duct nacelle configurations were the same. The channel pressures measured at Calspan were in good agreement with those measured at Ames for the baseline long-duct nacelle. The incremental drag for the revised nacelle was measured as two to four counts (three counts is approximately equal to one percent of the airplane drag) higher than that of the baseline long-duct nacelle.

Parametric study of electromagnetic waves propagating in absorbing curved S ducts

NASA Technical Reports Server (NTRS)

Baumeister, Kenneth J.

1989-01-01

A finite-element Galerkin formulation has been developed to study attenuation of transverse magnetic (TM) waves propagating in two-dimensional S-curved ducts with absorbing walls. In the frequency range where the duct diameter and electromagnetic wave length are nearly equal, the effect of duct length, curvature (duct offset), and absorber wall thickness was examined. For a given offset in the curved duct, the length of the S-duct was found to significantly affect both the absorptive and reflective characteristics of the duct. For a straight and a curved duct with perfect electric conductor terminations, power attenuation contours were examined to determine electromagnetic wall properties associated with maximum input signal absorption. Offset of the S-duct was found to significantly affect the value of the wall permittivity associated with the optimal attenuation of the incident electromagnetic wave.

Leaf seal for transition duct in turbine system

DOEpatents

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston; Dillard, Daniel Jackson; Pentecost, Ronnie Ray

2013-06-11

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a leaf seal contacting the interface member to provide a seal between the interface member and the turbine section.

[Clinicopathologic features of drug-induced vanishing bile duct syndrome].

PubMed

Ye, L H; Wang, C K; Zhang, H C; Liu, Z Q; Zheng, H W

2017-04-20

Vanishing bile duct syndrome (VBDS) manifests as progressive destruction and disappearance of the intrahepatic bile duct caused by various factors and cholestasis. VBDS associated with drug-induced liver injury (D-VBDS) is an important etiology of VBDS, and immune disorder or immune imbalance may be the main pathogenesis. According to its clinical symptoms, serological markers, and course of the disease, D-VBDS is classified into major form and minor form, and its clinical features are based on various pathomorphological findings. Its prognosis is associated various factors including regeneration of bile duct cells, number of bile duct injuries, level and range of bile duct injury, bile duct proliferation, and compensatory shunt of bile duct branches. This disease has various clinical outcomes; most patients have good prognosis after drug withdrawal, and some patients may experience cholestatic cirrhosis, liver failure, and even death. Due to the clinical manifestation and biochemical changes are similar to the primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), it need to identify by clinical physician.

Bile Duct Cancer (Cholangiocarcinoma) Treatment (PDQ®)—Health Professional Version

Cancer.gov

Bile duct cancer (also called cholangiocarcinoma) can occur in the bile ducts in the liver (intrahepatic) or outside the liver (perihilar or distal extrahepatic). Learn about the types of bile duct cancer, risk factors, clinical features, staging, and treatment for bile duct cancer in this expert-reviewed summary.

Multi-level obstruction in obstructive sleep apnoea: prevalence, severity and predictive factors.

PubMed

Phua, C Q; Yeo, W X; Su, C; Mok, P K H

2017-11-01

To characterise multi-level obstruction in terms of prevalence, obstructive sleep apnoea severity and predictive factors, and to collect epidemiological data on upper airway morphology in obstructive sleep apnoea patients. Retrospective review of 250 obstructive sleep apnoea patients. On clinical examination, 171 patients (68.4 per cent) had multi-level obstruction, 49 (19.6 per cent) had single-level obstruction and 30 (12 per cent) showed no obstruction. Within each category of obstructive sleep apnoea severity, multi-level obstruction was more prevalent. Multi-level obstruction was associated with severe obstructive sleep apnoea (more than 30 events per hour) (p = 0.001). Obstructive sleep apnoea severity increased with the number of obstruction sites (correlation coefficient = 0.303, p < 0.001). Multi-level obstruction was more likely in younger (p = 0.042), male (p = 0.045) patients, with high body mass index (more than 30 kg/m2) (p < 0.001). Palatal (p = 0.004), tongue (p = 0.026) and lateral pharyngeal wall obstructions (p = 0.006) were associated with severe obstructive sleep apnoea. Multi-level obstruction is more prevalent in obstructive sleep apnoea and is associated with increased severity. Obstruction at certain anatomical levels contributes more towards obstructive sleep apnoea severity.

Measure Guideline: Buried and/or Encapsulated Ducts

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

Shapiro, C.; Zoeller, W.; Mantha, P.

2013-08-01

Buried and/or encapsulated ducts (BEDs) are a class of advanced, energy-efficiency strategies intended to address the significant ductwork thermal losses associated with ducts installed in unconditioned attics. BEDs are ducts installed in unconditioned attics that are covered in loose-fill insulation and/or encapsulated in closed cell polyurethane spray foam insulation. This Measure Guideline covers the technical aspects of BEDs as well as the advantages, disadvantages, and risks of BEDs compared to other alternative strategies. This guideline also provides detailed guidance on installation of BEDs strategies in new and existing homes through step-by-step installation procedures. Some of the procedures presented here, however,more » require specialized equipment or expertise. In addition, some alterations to duct systems may require a specialized license.« less

Partially covered versus uncovered self-expandable nitinol stents with anti-migration properties for the palliation of malignant distal biliary obstruction: A randomized controlled trial.

PubMed

Yang, Min Jae; Kim, Jin Hong; Yoo, Byung Moo; Hwang, Jae Chul; Yoo, Jun Hwan; Lee, Ki Seong; Kang, Joon Koo; Kim, Soon Sun; Lim, Sun Gyo; Shin, Sung Jae; Cheong, Jae Youn; Lee, Kee Myung; Lee, Kwang Jae; Cho, Sung Won

2015-01-01

Covered self-expandable metal stents (SEMSs) are increasingly used as alternatives to uncovered SEMSs for the palliation of inoperable malignant distal biliary obstruction to counteract tumor ingrowth. We aimed to compare the outcomes of partially covered and uncovered SEMSs with identical mesh structures and anti-migration properties, such as low axial force and flared ends. One hundred and three patients who were diagnosed with inoperable malignant distal biliary obstruction between January 2006 and August 2013 were randomly assigned to either the partially covered (n = 51) or uncovered (n = 52) SEMS group. There were no significant differences in the cumulative stent patency, overall patient survival, stent dysfunction-free survival and overall adverse events, including pancreatitis and cholecystitis, between the two groups. Compared to the uncovered group, stent migration (5.9% vs. 0%, p = 0.118) and tumor overgrowth (7.8% vs. 1.9%, p = 0.205) were non-significantly more frequent in the partially covered group, whereas tumor ingrowth showed a significantly higher incidence in the uncovered group (5.9% vs. 19.2%, p = 0.041). Stent migration in the partially covered group occurred only in patients with short stenosis of the utmost distal bile duct (two in ampullary cancer, one in bile duct cancer), and did not occur in any patients with pancreatic cancer. For the palliation of malignant distal biliary obstruction, endoscopic placement of partially covered SEMSs with anti-migration designs and identical mesh structures to uncovered SEMSs failed to prolong cumulative stent patency or reduce stent migration.

"TuNa-saving" endoscopic medial maxillectomy: a surgical technique for maxillary inverted papilloma.

PubMed

Pagella, Fabio; Pusateri, Alessandro; Matti, Elina; Avato, Irene; Zaccari, Dario; Emanuelli, Enzo; Volo, Tiziana; Cazzador, Diego; Citraro, Leonardo; Ricci, Giampiero; Tomacelli, Giovanni Leo

2017-07-01

The maxillary sinus is the most common site of sinonasal inverted papilloma. Endoscopic sinus surgery, in particular endoscopic medial maxillectomy, is currently the gold standard for treatment of maxillary sinus papilloma. Although a common technique, complications such as stenosis of the lacrimal pathway and consequent development of epiphora are still possible. To avoid these problems, we propose a modification of this surgical technique that preserves the head of the inferior turbinate and the nasolacrimal duct. A retrospective analysis was performed on patients treated for maxillary inverted papilloma in three tertiary medical centres between 2006 and 2014. Pedicle-oriented endoscopic surgery principles were applied and, in select cases where the tumour pedicle was located on the anterior wall, a modified endoscopic medial maxillectomy was carried out as described in this paper. From 2006 to 2014 a total of 84 patients were treated. A standard endoscopic medial maxillectomy was performed in 55 patients (65.4%), while the remaining 29 (34.6%) had a modified technique performed. Three recurrences (3/84; 3.6%) were observed after a minimum follow-up of 24 months. A new surgical approach for select cases of maxillary sinus inverted papilloma is proposed in this paper. In this technique, the endoscopic medial maxillectomy was performed while preserving the head of the inferior turbinate and the nasolacrimal duct ("TuNa-saving"). This technique allowed for good visualization of the maxillary sinus, good oncological control and a reduction in the rate of complications.

Ultrasound imaging of the mouse pancreatic duct using lipid microbubbles

NASA Astrophysics Data System (ADS)

Banerjee, B.; McKeown, K. R.; Skovan, B.; Ogram, E.; Ingram, P.; Ignatenko, N.; Paine-Murrieta, G.; Witte, R.; Matsunaga, T. O.

2012-03-01

Research requiring the murine pancreatic duct to be imaged is often challenging due to the difficulty in selectively cannulating the pancreatic duct. We have successfully catheterized the pancreatic duct through the common bile duct in severe combined immune deficient (SCID) mice and imaged the pancreatic duct with gas filled lipid microbubbles that increase ultrasound imaging sensitivity due to exquisite scattering at the gas/liquid interface. A SCID mouse was euthanized by CO2, a midline abdominal incision made, the common bile duct cut at its midpoint, a 2 cm, 32 gauge tip catheter was inserted about 1 mm into the duct and tied with suture. The duodenum and pancreas were excised, removed in toto, embedded in agar and an infusion pump was used to instill normal saline or lipid-coated microbubbles (10 million / ml) into the duct. B-mode images before and after infusion of the duct with microbubbles imaged the entire pancreatic duct (~ 1 cm) with high contrast. The microbubbles were cavitated by high mechanical index (HMI) ultrasound for imaging to be repeated. Our technique of catheterization and using lipid microbubbles as a contrast agent may provide an effective, affordable technique of imaging the murine pancreatic duct; cavitation with HMI ultrasound would enable repeated imaging to be performed and clustering of targeted microbubbles to receptors on ductal cells would allow pathology to be localized accurately. This research was supported by the Experimental Mouse Shared Service of the AZ Cancer Center (Grant Number P30CA023074, NIH/NCI and the GI SPORE (NIH/NCI P50 CA95060).

Convolution seal for transition duct in turbine system

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

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston

2015-03-10

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a convolution seal contacting the interface member to provide a seal between the interface member and themore » turbine section.« less

Acoustic radiation from lined, unflanged ducts: Acoustic source distribution program

NASA Technical Reports Server (NTRS)

Beckemeyer, R. J.; Sawdy, D. T.

1971-01-01

An acoustic radiation analysis was developed to predict the far-field characteristics of fan noise radiated from an acoustically lined unflanged duct. This analysis is comprised of three modular digital computer programs which together provide a capability of accounting for the impedance mismatch at the duct exit plane. Admissible duct configurations include circular or annular, with or without an extended centerbody. This variation in duct configurations provides a capability of modeling inlet and fan duct noise radiation. The computer programs are described in detail.

[Bile duct lesions in laparoscopic cholecystectomy].

PubMed

Siewert, J R; Ungeheuer, A; Feussner, H

1994-09-01

Laparoscopic cholecystectomy is both resulting in a slightly higher incidence of biliary lesions and a change of prevalence of the type of lesions. Damage to the biliary system occurs in 4 different types: The most severe case is the lesion with a structural defect of the hepatic or common bile duct with (IVa) or without (IVb) vascular injury. Tangential lesions without structural loss of the duct should be denominated as type III (IIIa with additional lesion to the vessels, type IIIb without). Type II comprehends late strictures without obvious intraoperative trauma to the duct. Type I includes immediate biliary fistulae of usually good prognosis. The increasing prevalence of structural defects of the bile ducts appears to be a peculiarity of laparoscopic cholecystectomy necessitating highly demanding operative repair. In the majority of cases, hepatico-jejunostomy or even intraparenchymatous anastomoses are required. Adaptation of well proven principles of open surgery is the best prevention of biliary lesions in laparoscopic cholecystectomy as well as the readiness to convert early to the open procedure.

HVAC; Heating, Ventilation, Air Conditioning - Aerosol Duct Sealant

DTIC Science & Technology

2016-09-01

material was applied. Annual energy and cost savings were predicted based on a typical weather year for each site. The installation of the duct...Balance reports; Visible dust streaks on duct work, ceilings near supply diffusers, or electrical boxes; Comfort complaints Specific Leakage...energy consumption , depending on the HVAC system type and the location of the ducts that were sealed. The cost effectiveness of the technology is

Measure Guideline: Buried and/or Encapsulated Ducts

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

Shapiro, C.; Zoeller, W.; Mantha, P.

2013-08-01

Buried and/or encapsulated ducts (BEDs) are a class of advanced, energy-efficiency strategies intended to address the significant ductwork thermal losses associated with ducts installed in unconditioned attics. BEDs are ducts installed in unconditioned attics that are covered in loose-fill insulation and/or encapsulated in closed cell polyurethane spray foam insulation. This Measure Guideline covers the technical aspects of BEDs as well as the advantages, disadvantages, and risks of BEDs compared to other alternative strategies. This guideline also provides detailed guidance on installation of BEDs strategies in new and existing homes through step-by-step installation procedures. This Building America Measure Guideline synthesizes previouslymore » published research on BEDs and provides practical information to builders, contractors, homeowners, policy analysts, building professions, and building scientists. Some of the procedures presented here, however, require specialized equipment or expertise. In addition, some alterations to duct systems may require a specialized license. Persons implementing duct system improvements should not go beyond their expertise or qualifications. This guideline provides valuable information for a building industry that has struggled to address ductwork thermal losses in new and existing homes. As building codes strengthen requirements for duct air sealing and insulation, flexibility is needed to address energy efficiency goals. While ductwork in conditioned spaces has been promoted as the panacea for addressing ductwork thermal losses, BEDs installations approach - and sometimes exceed - the performance of ductwork in conditioned spaces.« less

Acoustic energy in ducts - Further observations

NASA Technical Reports Server (NTRS)

Eversman, W.

1979-01-01

The transmission of acoustic energy in uniform ducts carrying uniform flow is investigated with the purpose of clarifying two points of interest. The two commonly used definitions of acoustic 'energy' flux are shown to be related by a Legendre transformation of the Lagrangian density exactly as in deriving the Hamiltonian density in mechanics. In the acoustic case the total energy density and the Hamiltonian density are not the same which accounts for two different 'energy' fluxes. When the duct has acoustically absorptive walls neither of the two flux expressions gives correct results. A reevaluation of the basis of derivation of the energy density and energy flux provides forms which yield consistent results for soft walled ducts.

Characterization of flow in a scroll duct

NASA Technical Reports Server (NTRS)

Begg, E. K.; Bennett, J. C.

1985-01-01

A quantitative, flow visualization study was made of a partially elliptic cross section, inward curving duct (scroll duct), with an axial outflow through a vaneless annular cutlet. The working fluid was water, with a Re(d) of 40,000 at the inlet to the scroll duct, this Reynolds number being representative of the conditions in an actual gas turbine scroll. Both still and high speed moving pictures of fluorescein dye injected into the flow and illuminated by an argon ion laser were used to document the flow. Strong secondary flow, similar to the secondary flow in a pipe bend, was found in the bottom half of the scroll within the first 180 degs of turning. The pressure field set up by the turning duct was strong enough to affect the inlet flow condition. At 90 degs downstream, the large scale secondary flow was found to be oscillatory in nature. The exit flow was nonuniform in the annular exit. By 270 degs downstream, the flow appeared unorganized with no distinctive secondary flow pattern. Large scale structures from the upstream core region appeared by 90 degs and continued through the duct to reenter at the inlet section.

[Bile duct lesions repaired with peritoneal tube grafts].

PubMed

Lorenzana-Bautista, Ileana; Flores-Plascencia, Aníbal; Barrios-Pineda, Francisco Javier; Alderete-Vázquez, Georgia; Sánchez-Valdivieso, Enrique Alejandro

2013-01-01

A significant number of people suffer iatrogenic bile duct injury during laparoscopic cholescystectomy. Biliary-digestive bypass may be complicated by stenosis and biliary sepsis, affecting both quality of life and life expectancy. To avoid bypass synthetic grafts have been used, which are expensive. Evaluating autologous implantation of peritoneus as alternative of bile duct repair. Under general anesthesia, ten New Zealand adult rabbits were operated, common bile duct approached and sectioned underneath the cystic duct followed by a liver biopsy. An autologous graft was built of peritoneum and graft-bile duct proximal and distal end-to-end anastomosis done. Animals were followed-up by weekly bilirrubin and transferases. Rabbits were scheduled euthanized and a liver biopsy done for histological examinations. Autologous graft was easy to create and all rabbits survived. They did not develop jaundice or alterations in their normal habits. At necropsy, autologous grafts were removed and no signs of occlusion were noticed. Moderate short-term liver damage was observed but long-term damage was negligible. Bileoma and pyogenic liver abscess were observed in two animals, respectively. Our results favourably match well-known procedures used for bile duct repair, especially in cases of severe injury (Bismuth-Strasberg E1-3): it seems less complicated than biliary-digestive bypass, not as expensive as synthetic grafts, and much easier to build than human amnion graft. Interposing an autologous graft of peritoneum is an easy-to-create surgical procedure and circumferential bile duct injuries were adequately repaired.

Borescope Device Takes Impressions In Ducts

NASA Technical Reports Server (NTRS)

Walter, Richard F.; Turner, Laura J.

1990-01-01

Maneuverable device built around borescope equipped to make impression molds of welded joints in interior surfaces of ducts. Molds then examined to determine degress of mismatch in welds. Inserted in duct, and color-coded handles on ends of cables used to articulate head to maneuver around corners. Use of device fairly easy and requires little training.

A non-local computational boundary condition for duct acoustics

NASA Technical Reports Server (NTRS)

Zorumski, William E.; Watson, Willie R.; Hodge, Steve L.

1994-01-01

A non-local boundary condition is formulated for acoustic waves in ducts without flow. The ducts are two dimensional with constant area, but with variable impedance wall lining. Extension of the formulation to three dimensional and variable area ducts is straightforward in principle, but requires significantly more computation. The boundary condition simulates a nonreflecting wave field in an infinite duct. It is implemented by a constant matrix operator which is applied at the boundary of the computational domain. An efficient computational solution scheme is developed which allows calculations for high frequencies and long duct lengths. This computational solution utilizes the boundary condition to limit the computational space while preserving the radiation boundary condition. The boundary condition is tested for several sources. It is demonstrated that the boundary condition can be applied close to the sound sources, rendering the computational domain small. Computational solutions with the new non-local boundary condition are shown to be consistent with the known solutions for nonreflecting wavefields in an infinite uniform duct.

On Computations of Duct Acoustics with Near Cut-Off Frequency

NASA Technical Reports Server (NTRS)

Dong, Thomas Z.; Povinelli, Louis A.

1997-01-01

The cut-off is a unique feature associated with duct acoustics due to the presence of duct walls. A study of this cut-off effect on the computations of duct acoustics is performed in the present work. The results show that the computation of duct acoustic modes near cut-off requires higher numerical resolutions than others to avoid being numerically cut off. Duct acoustic problems in Category 2 are solved by the DRP finite difference scheme with the selective artificial damping method and results are presented and compared to reference solutions.

Bile duct injury during cholecystectomy.

PubMed

Kapoor, V K

2015-08-01

Laparoscopic cholecystectomy (LC) is the treatment of choice for gallstones, but is associated with increased risk of bile duct injury (BDI bile duct injury). If the BDI is detected during LC can be addressed immediately, if available hepatobiliary surgeon, but the easiest and safest procedure for the general surgeon is placing drains into subhepatic region and the transfer of acute BDI to controlled external biliary fistula (external Biliary fistula EBF). Most BDI is diagnosed when the postoperative period, when there is biliary leak. Therapy is a percutaneous catheter drainage and endoscopic stenting in the bile duct; early repair is not recommended. Repair in the form hepatico-jejunostomy (HJ) should be performed hepatobiliary surgeon at intervals of 46 weeks after it closes EBF. BDI is a frequent cause medico-legal actions and a substantial burden on health care costs. Most BDI can be avoided by adherence to the principles of safe cholecystectomy.

Outcomes and risk factors for cancer patients undergoing endoscopic intervention of malignant biliary obstruction.

PubMed

Haag, Georg-Martin; Herrmann, Thomas; Jaeger, Dirk; Stremmel, Wolfgang; Schemmer, Peter; Sauer, Peter; Gotthardt, Daniel Nils

2015-12-04

Malignant bile duct obstruction is a common problem among cancer patients with hepatic or lymphatic metastases. Endoscopic retrograde cholangiography (ERC) with the placement of a stent is the method of choice to improve biliary flow. Only little data exist concerning the outcome of patients with malignant biliary obstruction in relationship to microbial isolates from bile. Bile samples were taken during the ERC procedure in tumor patients with biliary obstruction. Clinical data including laboratory values, tumor-specific treatment and outcome data were prospectively collected. 206 ERC interventions in 163 patients were recorded. In 43 % of the patients, systemic treatment was (re-) initiated after successful biliary drainage. A variety of bacteria and fungi was detected in the bile samples. One-year survival was significantly worse in patients from whom multiresistant pathogens were isolated than in patients, in whom other species were detected. Increased levels of inflammatory markers were associated with a poor one-year survival. The negative impact of these two factors was confirmed in multivariate analysis. In patients with pancreatic cancer, univariate analysis showed a negative impact on one-year survival in case of detection of Candida species in the bile. Multivariate analysis confirmed the negative prognostic impact of Candida in the bile in pancreatic cancer patients. Outcome in tumor patients with malignant bile obstruction is associated with the type of microbial biliary colonization. The proof of multiresistant pathogens or Candida, as well as the level of inflammation markers, have an impact on the prognosis of the underlying tumor disease.

Usefulness of transpapillary bile duct brushing cytology and forceps biopsy for improved diagnosis in patients with biliary strictures.

PubMed

Kitajima, Yasuhiro; Ohara, Hirotaka; Nakazawa, Takahiro; Ando, Tomoaki; Hayashi, Kazuki; Takada, Hiroki; Tanaka, Hajime; Ogawa, Kanto; Sano, Hitoshi; Togawa, Shozo; Naito, Itaru; Hirai, Masaaki; Ueno, Koichiro; Ban, Tessin; Miyabe, Katuyuki; Yamashita, Hiroaki; Yoshimura, Norihiro; Akita, Shinji; Gotoh, Kazuo; Joh, Takashi

2007-10-01

Transpapillary bile duct brushing cytology and/or forceps biopsy was performed in the presence of an indwelling guidewire in patients with biliary stricture, and the treatment time, overall diagnosis rate, diagnosis rate of each disease, complications, and influences on subsequent biliary drainage were investigated. After endoscopic retrograde cholangiography, brushing cytology was performed, followed by forceps biopsy. In patients with obstructive jaundice, endoscopic biliary drainage (EBD) was subsequently performed. To investigate the influences of bile duct brushing cytology and forceps biopsy on EBD, patients who underwent subsequent EBD by plastic stent were compared with patients who underwent EBD alone. The samples for cytology were collected successfully in all cases, and the sensitivity for malignancy/benignity, specificity, and accuracy were 71.6%, 100%, and 75.0%, respectively. The biopsy sampling was successful in 51 patients, and samples applicable to the evaluation were collected in all 51 patients. The sensitivity for malignancy/benignity, specificity, and accuracy were 65.2%, 100%, and 68.6%, respectively. Combination of the two procedures increased the sensitivity and accuracy to 73.5% and 76.6%, respectively. The time required for cytology and biopsy was 11.7 min, which is relatively short. Cytology and biopsy did not affect drainage. Regarding accidents, bile duct perforation occurred during biopsy in one patient (1.9%), but was rapidly improved by endoscopic biliary drainage. Transpapillary brushing cytology and forceps biopsy could be performed in a short time. The diagnosis rate was high, and the incidence of complication was low, having no influence on subsequent biliary drainage.

DUCT RETROFIT STRATEGY TO COMPLEMENT A MODULATING FURNACE.

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

ANDREWS,J.W.

2002-10-02

Some recent work (Walker 2001, Andrews 2002) has indicated that installing a modulating furnace in a conventional duct system may, in many cases, result in a significant degradation in thermal distribution efficiency. The fundamental mechanism was pointed out nearly two decades ago (Andrews and Krajewski 1985). The problem occurs in duct systems that are less-than-perfectly insulated (e.g., R-4 duct wrap) and are located outside the conditioned space. It stems from the fact that when the airflow rate is reduced, as it will be when the modulating furnace reduces its heat output rate, the supply air will have a longer residencemore » time in the ducts and will therefore lose a greater percentage of its heat by conduction than it did at the higher airflow rate. The impact of duct leakage, on the other hand, is not expected to change very much under furnace modulation. The pressures in the duct system will be reduced when the airflow rate is reduced, thus reducing the leakage per unit time. This is balanced by the fact that the operating time will increase in order to meet the same heating load as with the conventional furnace operating at higher output and airflow rates. The balance would be exact if the exponent in the pressure vs. airflow equation were the same as that in the pressure vs. duct leakage equation. Since the pressure-airflow exponent is usually {approx}0.5 and the pressure-leakage exponent is usually {approx}0.6, the leakage loss as a fraction of the load should be slightly lower for the modulating furnace. The difference, however, is expected to be small, determined as it is by a function with an exponent equal to the difference between the above two exponents, or {approx}0.1. The negative impact of increased thermal conduction losses from the duct system may be partially offset by improved efficiency of the modulating furnace itself. Also, the modulating furnace will cycle on and off less often than a single-capacity model, and this may add a small

Inlets, ducts, and nozzles

NASA Technical Reports Server (NTRS)

Abbott, John M.; Anderson, Bernhard H.; Rice, Edward J.

1990-01-01

The internal fluid mechanics research program in inlets, ducts, and nozzles consists of a balanced effort between the development of computational tools (both parabolized Navier-Stokes and full Navier-Stokes) and the conduct of experimental research. The experiments are designed to better understand the fluid flow physics, to develop new or improved flow models, and to provide benchmark quality data sets for validation of the computational methods. The inlet, duct, and nozzle research program is described according to three major classifications of flow phenomena: (1) highly 3-D flow fields; (2) shock-boundary-layer interactions; and (3) shear layer control. Specific examples of current and future elements of the research program are described for each of these phenomenon. In particular, the highly 3-D flow field phenomenon is highlighted by describing the computational and experimental research program in transition ducts having a round-to-rectangular area variation. In the case of shock-boundary-layer interactions, the specific details of research for normal shock-boundary-layer interactions are described. For shear layer control, research in vortex generators and the use of aerodynamic excitation for enhancement of the jet mixing process are described.

Pancreatic-duct-lavage cytology in candidates for surgical resection of branch-duct intraductal papillary mucinous neoplasm of the pancreas: should the International Consensus Guidelines be revised?

PubMed

Sai, Jin Kan; Suyama, Masafumi; Kubokawa, Yoshihiro; Watanabe, Sumio; Maehara, Tadayuki

2009-03-01

The International Consensus Guidelines are helpful for the management of branch-duct intraductal papillary mucinous neoplasms (IPMNs), because they allow us to exclude malignancy. However, it is not possible to predict malignancy with certainty, and further preoperative differentiation between benign and malignant IPMNs is required to avoid the false-positive results. To examine the usefulness of pancreatic-duct-lavage cytology by using an originally designed double-lumen catheter for discriminating benign and malignant IPMNs of the branch-duct type in candidates for surgical resection based on the International Consensus Guidelines. Pancreatic-duct-lavage cytology was investigated in 24 patients with branch-duct IPMNs who underwent surgical resection based on the International Consensus Guidelines, namely, they either had intramural nodules or the ectatic branch duct was >30 mm in diameter. Single-center retrospective study. Academic medical center. The sensitivity and specificity of pancreatic-duct-lavage cytology for discriminating benign from malignant IPMNs. More than 30 mL of pancreatic-duct-lavage fluid was obtained from each patient, and there were no patients with noninformative results. The sensitivity, specificity, positive predictive value, and negative predictive value of the cytologic diagnosis were 78%, 93%, 88%, and 88%, respectively. Single-center and small number of patients. Pancreatic-duct-lavage cytology can improve differentiation between benign and malignant IPMNs of the branch-duct type in candidates for surgical resection based on the International Consensus Guidelines.

[Syncrhonous carcinosarcoma of the extrahepatic bile duct and gallbladder.

PubMed

Páramo, Ana Alberca; Valverde, David Padilla; Campos, Pedro Villarejo; Santos, Esther Pilar Garcia; Puche, Jose Luis Bertelli; Guerrero, Paloma Núńez; Delgado, Margarita; Fernindez, Jesus Martin

2016-03-01

Carcinosarcoma is a malignant neoplasm characterized for intermingled epithelial and mesenchymal components. A preoperative suspected diagnosis will allow a radical therapy avoiding a very bad prognosis. We report on a male patient who was operated in our Service with diagnosis of synchronous carcinosarcoma of gallbladder and extrahepatic bile duct and a review of the Medical Literature. A gallblader carcinosarcoma showing extension into common bile duct is very rare, a carcinosarcoma of the bile duct is exceptional, and a synchronous carcinosarcoma ofthe bile duct and gallbladder has not been reported previously.

Anomalous pancreatico-biliary ductal union with cystic dilatation of the bile duct.

PubMed

Richer, J P; Faure, J P; Morichau-Beauchant, M; Dugue, T; Maillot, N; Kamina, P; Carretier, M

1998-01-01

We report, in an adult, an asymptomatic association between cystic dilation of the bile duct (type IV A in Todani's classification) and anomalous pancreatico-biliary ductal union (APBD) with stones in a long common channel. In APBD, the connection between the common bile duct and the main pancreatic duct is located outside the duodenal wall andis therefore not under the influence of the sphincter of Boyden. An abnormally long common channel is in excess of 15 mm. Two types of convergence anomalies are defined according to whether the bile duct opens into the main pancreatic duct (BP) or the main pancreatic duct into the bile duct (PB). In APBD, there is probably a reverse pressure gradient between the bile and pancreatic ducts, with regurgitation of pancreatic juice into the bile duct, repeated attacks of cholangitis, stenosis and cystic dilatation. A long common channel is associated with a higher incidence of carcinoma of the gall bladder of the bile duct.

Fluid flow in a spiral microfluidic duct

NASA Astrophysics Data System (ADS)

Harding, Brendan; Stokes, Yvonne

2018-04-01

We consider the steady, pressure driven flow of a viscous fluid through a microfluidic device having the geometry of a planar spiral duct with a slowly varying curvature and height smaller than width. For this problem, it is convenient to express the Navier-Stokes equations in terms of a non-orthogonal coordinate system. Then, after applying appropriate scalings, the leading order equations admit a relatively simple solution in the central region of the duct cross section. First-order corrections with respect to the duct curvature and aspect ratio parameters are also obtained for this region. Additional correction terms are needed to ensure that no slip and no penetration conditions are satisfied on the side walls. Our solutions allow for a top wall shape that varies with respect to the radial coordinate which allows us to study the flow in a variety of cross-sectional shapes, including trapezoidal-shaped ducts that have been studied experimentally. At leading order, the flow is found to depend on the local height and slope of the top wall within the central region. The solutions are compared with numerical approximations of a classical Dean flow and are found to be in good agreement for a small duct aspect ratio and a slowly varying and small curvature. We conclude that the slowly varying curvature typical of spiral microfluidic devices has a negligible impact on the flow in the sense that locally the flow does not differ significantly from the classical Dean flow through a duct having the same curvature.

Investigation of the tone-burst tube for duct lining attenuation measurement

NASA Technical Reports Server (NTRS)

Soffel, A. R.; Morrow, P. F.

1972-01-01

The tone burst technique makes practical the laboratory evaluation of potential inlet and discharge duct treatments. Tone burst apparatus requires only simple machined parts and standard components. Small, simply made, lining samples are quickly and easily installed in the system. Two small electromagnetric loudspeaker drivers produce peak sound pressure level of over 166 db in the 3-square-inch sample duct. Air pump available in most laboratories can produce air flows of over plus and minus Mach 0.3 in the sample duct. The technique uses short shaped pulses of sound propagated down a progressive wave tube containing the sample duct. The peak pressure level output of the treated duct is compared with the peak pressure level output of a substituted reference duct. The difference between the levels is the attenuation or insertion loss of the treated duct. Evaluations of resonant absorber linings by the tone burst technique check attenuation values predicted by empirical formulas based on full scale ducts.

Post-Tensioning Duct Air Pressure Testing Effects on Web Cracking

DOT National Transportation Integrated Search

2015-01-01

Nevada Department of Transportation (NDOT) post-tensioned concrete bridges have experienced web cracking near the post-tensioning ducts during the construction process. The ducts were air pressure tested to ensure the duct can successfully be grouted...

Endoluminal Intervention in the Salivary Duct: Clinical Outcomes at a District General Hospital

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

Nagra, I.; Jones, C.; Dyer, J., E-mail: Jules.Dyer@rwh-tr.nhs.u

Our aim was to assess the preliminary clinical outcomes of interventional radiology for salivary duct obstruction in relation to salivary duct strictures or calculi. A retrospective analysis of consecutive patients referred for endoluminal procedures by ENT surgeons during a 4-year period were identified. The procedure was performed by a single interventional radiologist under fluoroscopic guidance using wire baskets and angioplasty balloons. Between June 2004 and October 2008, 50 sialoplasties were performed in 43 patients (30 female and 13 male). Twenty-six patients were prepared for 32 procedures for extraction of calculi (13 submandibular and 13 parotid), and 17 patients had 18more » procedures for strictures (16 parotid and 1 submandibular). One patient in the group with calculi was judged unsuitable for intervention because the stone had migrated outside the salivary duct. Information was collected regarding the clinical indication; duration and type of symptoms; technical factors; follow-up; and success or failure of reintervention. Complete stone removal was achieved in 18 of the 26 patients (69%), with success on the first attempt in 14 patients (54%). Redo procedures were required in 4 patients (15%), with subsequent complete clearance of calculi. In this cohort, 20 patients were symptomatically improved (77%). Of the 6 patients (26%) with continuing symptoms, 2 patients had mild symptoms; two had moderate symptoms; and two patients opted to have surgery for unremitting symptoms. In the stricture group, 18 procedures were performed in 17 patients, with a successful outcome in 16 patients after the initial sialoplasty. Only 1 patient required repeat intervention (6%) and later opted to have surgery for continuing symptoms. In this group, 14 patients (82%) were symptomatically improved, and 3 remained symptomatic despite a good immediate result due to restenosis. Two patients experienced early complications: One had a transient facial nerve palsy, and the

Energy efficient engine: Turbine transition duct model technology report

NASA Technical Reports Server (NTRS)

Leach, K.; Thurlin, R.

1982-01-01

The Low-Pressure Turbine Transition Duct Model Technology Program was directed toward substantiating the aerodynamic definition of a turbine transition duct for the Energy Efficient Engine. This effort was successful in demonstrating an aerodynamically viable compact duct geometry and the performance benefits associated with a low camber low-pressure turbine inlet guide vane. The transition duct design for the flight propulsion system was tested and the pressure loss goal of 0.7 percent was verified. Also, strut fairing pressure distributions, as well as wall pressure coefficients, were in close agreement with analytical predictions. Duct modifications for the integrated core/low spool were also evaluated. The total pressure loss was 1.59 percent. Although the increase in exit area in this design produced higher wall loadings, reflecting a more aggressive aerodynamic design, pressure profiles showed no evidence of flow separation. Overall, the results acquired have provided pertinent design and diagnostic information for the design of a turbine transition duct for both the flight propulsion system and the integrated core/low spool.

Liver and Bile Duct Cancer—Patient Version

Cancer.gov

Liver cancer includes hepatocellular carcinoma and bile duct cancer (cholangiocarcinoma). Risk factors for HCC include chronic infection with hepatitis B or C and cirrhosis of the liver. Start here to find information on liver and bile duct cancer treatment, causes and prevention, screening, research, and statistics.

Bile duct anastomotic stricture after pediatric living donor liver transplantation.

PubMed

Chok, Kenneth S H; Chan, See Ching; Chan, Kwong Leung; Sharr, William W; Tam, Paul K H; Fan, Sheung Tat; Lo, Chung Mau

2012-07-01

Hepaticojejunostomy is a well-accepted method, whereas duct-to-duct anastomosis is gaining popularity for bile duct reconstruction in pediatric living donor liver transplantation (LDLT). Biliary complications, especially biliary anastomotic stricture (BAS), are not clearly defined. The aim of the present study is to determine the rate of BAS and its associated risk factors. The study included 78 pediatric patients (<18 years old) who underwent LDLT during the period from end of September 1993 to end of November 2010. The diagnosis of BAS was based on clinical, biochemical, histologic, and radiologic results. All patients received left-side grafts. Thirteen patients (16.7%) developed BAS after LDLT. Among them, 3 patients (23.1%) had duct-to-duct anastomosis during LDLT. The median follow-up period for the BAS group and the non-BAS group was 57.8 and 79.5 months, respectively (P = .683). Ten of the patients with BAS required percutaneous transhepatic biliary drainage with or without dilatation for treating the stricture. Multivariable analysis showed that hepatic artery thrombosis and duct-to-duct anastomosis were 2 risk factors associated with BAS. In pediatric LDLT, hepaticojejunostomy is the preferred method for bile duct reconstruction, but more large-scale research needs to be done to reconfirm this result. Copyright © 2012 Elsevier Inc. All rights reserved.

Acoustic imaging of a duct spinning mode by the use of an in-duct circular microphone array.

PubMed

Wei, Qingkai; Huang, Xun; Peers, Edward

2013-06-01

An imaging method of acoustic spinning modes propagating within a circular duct simply with surface pressure information is introduced in this paper. The proposed method is developed in a theoretical way and is demonstrated by a numerical simulation case. Nowadays, the measurements within a duct have to be conducted using in-duct microphone array, which is unable to provide information of complete acoustic solutions across the test section. The proposed method can estimate immeasurable information by forming a so-called observer. The fundamental idea behind the testing method was originally developed in control theory for ordinary differential equations. Spinning mode propagation, however, is formulated in partial differential equations. A finite difference technique is used to reduce the associated partial differential equations to a classical form in control. The observer method can thereafter be applied straightforwardly. The algorithm is recursive and, thus, could be operated in real-time. A numerical simulation for a straight circular duct is conducted. The acoustic solutions on the test section can be reconstructed with good agreement to analytical solutions. The results suggest the potential and applications of the proposed method.

Choledochoscopic Holmium Laser Lithotripsy for Difficult Bile Duct Stones.

PubMed

Lv, Shangdong; Fang, Zheping; Wang, Aidong; Yang, Jian; Zhang, Wenlong

2017-01-01

The aim of this study was to evaluate the feasibility and efficacy of choledochoscopic holmium laser lithotripsy as a means of removing resistant extrahepatic and intrahepatic bile duct stones. Clinical data on 28 patients who had undergone choledochoscopic holmium laser lithotripsy were analyzed. Complete stone clearance was obtained in 24 patients; small numbers of residual stones in the left or right hepatic duct were found in 4 patients. No severe complications such as hemobilia and bile duct injuries occurred. Choledochoscopic holmium laser lithotripsy is a simple, safe, and effective treatment method for patients with resistant bile duct stones.

Flexible metallic seal for transition duct in turbine system

DOEpatents

Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston; Dillard, Daniel Jackson; Pentecost, Ronnie Ray

2014-04-22

A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a flexible metallic seal contacting the interface member to provide a seal between the interface member and the turbine section.

Observations of Strong Surface Radar Ducts over the Persian Gulf.

NASA Astrophysics Data System (ADS)

Brooks, Ian M.; Goroch, Andreas K.; Rogers, David P.

1999-09-01

Ducting of microwave radiation is a common phenomenon over the oceans. The height and strength of the duct are controlling factors for radar propagation and must be determined accurately to assess propagation ranges. A surface evaporation duct commonly forms due to the large gradient in specific humidity just above the sea surface; a deeper surface-based or elevated duct frequently is associated with the sudden change in temperature and humidity across the boundary layer inversion.In April 1996 the U.K. Meteorological Office C-130 Hercules research aircraft took part in the U.S. Navy Ship Antisubmarine Warfare Readiness/Effectiveness Measuring exercise (SHAREM-115) in the Persian Gulf by providing meteorological support and making measurements for the study of electromagnetic and electro-optical propagation. The boundary layer structure over the Gulf is influenced strongly by the surrounding desert landmass. Warm dry air flows from the desert over the cooler waters of the Gulf. Heat loss to the surface results in the formation of a stable internal boundary layer. The layer evolves continuously along wind, eventually forming a new marine atmospheric boundary layer. The stable stratification suppresses vertical mixing, trapping moisture within the layer and leading to an increase in refractive index and the formation of a strong boundary layer duct. A surface evaporation duct coexists with the boundary layer duct.In this paper the authors present aircraft- and ship-based observations of both the surface evaporation and boundary layer ducts. A series of sawtooth aircraft profiles map the boundary layer structure and provide spatially distributed estimates of the duct depth. The boundary layer duct is found to have considerable spatial variability in both depth and strength, and to evolve along wind over distances significant to naval operations (100 km). The depth of the evaporation duct is derived from a bulk parameterization based on Monin-Obukhov similarity theory

Liver Cholesterol Overload Aggravates Obstructive Cholestasis by Inducing Oxidative Stress and Premature Death in Mice.

PubMed

Nuño-Lámbarri, Natalia; Domínguez-Pérez, Mayra; Baulies-Domenech, Anna; Monte, Maria J; Marin, Jose J G; Rosales-Cruz, Patricia; Souza, Verónica; Miranda, Roxana U; Bucio, Leticia; Montalvo-Jave, Eduardo E; Concepción Gutiérrez-Ruiz, María; García-Ruiz, Carmen; Fernández-Checa, José C; Gomez-Quiroz, Luis Enrique

2016-01-01

Nonalcoholic steatohepatitis is one of the leading causes of liver disease. Dietary factors determine the clinical presentation of steatohepatitis and can influence the progression of related diseases. Cholesterol has emerged as a critical player in the disease and hence consumption of cholesterol-enriched diets can lead to a progressive form of the disease. The aim was to investigate the impact of liver cholesterol overload on the progression of the obstructive cholestasis in mice subjected to bile duct ligation surgery. Mice were fed with a high cholesterol diet for two days and then were subjected to surgery procedure; histological, biochemical, and molecular analyses were conducted to address the effect of cholesterol in liver damage. Mice under the diet were more susceptible to damage. Results show that cholesterol fed mice exhibited increased apoptosis and oxidative stress as well as reduction in cell proliferation. Mortality following surgery was higher in HC fed mice. Liver cholesterol impairs the repair of liver during obstructive cholestasis and aggravates the disease with early fatal consequences; these effects were strongly associated with oxidative stress.

Bile Duct Cancer (Cholangiocarcinoma)

MedlinePlus

... and pediatric oncologists, oncology nurses, physician assistants, social workers, and patient advocates. Cancer.Net Guide Bile Duct Cancer (Cholangiocarcinoma) ... Team Additional Resources View All Pages f ...

Results and comparison of Hall and DW duct experiments

NASA Technical Reports Server (NTRS)

Smith, J. M.; Morgan, J. L.

1982-01-01

Experimental data from recent tests of a 45 deg diagonal wall duct are presented and compared with the results of a similar Hall duct. It is shown that while the peak power density of the two devices is approximately equal that the diagonal wall duct produces greater total power output due to its ability to better utilize the available magnetic field.

Thrust control system design of ducted rockets

NASA Astrophysics Data System (ADS)

Chang, Juntao; Li, Bin; Bao, Wen; Niu, Wenyu; Yu, Daren

2011-07-01

The investigation of the thrust control system is aroused by the need for propulsion system of ducted rockets. Firstly the dynamic mathematical models of gas flow regulating system, pneumatic servo system and ducted rocket engine were established and analyzed. Then, to conquer the discussed problems of thrust control, the idea of information fusion was proposed to construct a new feedback variable. With this fused feedback variable, the thrust control system was designed. According to the simulation results, the introduction of the new fused feedback variable is valid in eliminating the contradiction between rapid response and stability for the thrust control system of ducted rockets.

Ducting arrangement for cooling a gas turbine structure

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

Lee, Ching-Pang; Morrison, Jay A.

2015-07-21

A ducting arrangement (10) for a can annular gas turbine engine, including: a duct (12, 14) disposed between a combustor (16) and a first row of turbine blades and defining a hot gas path (30) therein, the duct (12, 14) having raised geometric features (54) incorporated into an outer surface (80); and a flow sleeve (72) defining a cooling flow path (84) between an inner surface (78) of the flow sleeve (72) and the duct outer surface (80). After a cooling fluid (86) traverses a relatively upstream raised geometric feature (90), the inner surface (78) of the flow sleeve (72)more » is effective to direct the cooling fluid (86) toward a landing (94) separating the relatively upstream raised geometric feature (90) from a relatively downstream raised geometric feature (94).« less

Propagation Of Sound In Curved Ducts

NASA Technical Reports Server (NTRS)

Rostafinski, Wojciech

1992-01-01

Monograph presents concise, comprehensive summary of knowledge of propagation of acoustic waves in ducts and pipes including bends. Pulls together information from Lord Rayleigh's book Theory Of Sound, published in 1878, and from 33 papers scattered throughout various scientific journals published between 1945 and 1989. Monograph useful to scientists and engineers interested in such diverse topics as musical instruments, air-conditioning ducts, and jet engines. Material not available in current texts.

The pathophysiology of human obstructive cholestasis is mimicked in cholestatic Gold Syrian hamsters.

PubMed

van Golen, Rowan F; Olthof, Pim B; de Haan, Lianne R; Coelen, Robert J; Pechlivanis, Alexandros; de Keijzer, Mark J; Weijer, Ruud; de Waart, Dirk R; van Kuilenburg, André B P; Roelofsen, Jeroen; Gilijamse, Pim W; Maas, Martinus A; Lewis, Matthew R; Nicholson, Jeremy K; Verheij, Joanne; Heger, Michal

2018-03-01

Obstructive cholestasis causes liver injury via accumulation of toxic bile acids (BAs). Therapeutic options for cholestatic liver disease are limited, partially because the available murine disease models lack translational value. Profiling of time-related changes following bile duct ligation (BDL) in Gold Syrian hamsters revealed a biochemical response similar to cholestatic patients in terms of BA pool composition, alterations in hepatocyte BA transport and signaling, suppression of BA production, and adapted BA metabolism. Hamsters tolerated cholestasis well for up to 28days and progressed relatively slowly to fibrotic liver injury. Hepatocellular necrosis was absent, which coincided with preserved intrahepatic energy levels and only mild oxidative stress. The histological response to cholestasis in hamsters was similar to the changes seen in 17 patients with prolonged obstructive cholestasis caused by cholangiocarcinoma. Hamsters moreover upregulated hepatic fibroblast growth factor 15 (Fgf15) expression in response to BDL, which is a cytoprotective adaptation to cholestasis that hitherto had only been documented in cholestatic human livers. Hamster models should therefore be added to the repertoire of animal models used to study the pathophysiology of cholestatic liver disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Reconstruction of Bile Duct Injury and Defect with the Round Ligament.

PubMed

Dokmak, Safi; Aussilhou, Béatrice; Ragot, Emilia; Tantardini, Camille; Cauchy, François; Ponsot, Philippe; Belghiti, Jacques; Sauvanet, Alain; Soubrane, Olivier

2017-09-01

Lateral injury of the bile duct can occur after cholecystectomy, bile duct dissection, or exploration. If direct repair is not possible, conversion to bilioenteric anastomosis can be needed with the risk of long-term bile duct infections and associated complications. We developed a new surgical technique which consist of reconstructing the bile duct with the round ligament. The vascularized round ligament is completely mobilized until its origin and used for lateral reconstruction of the bile duct to cover the defect. T tube was inserted and removed after few months. Patency of the bile duct was assessed by cholangiography, the liver function test and magnetic resonance imaging (MRI). Two patients aged 33 and 59 years old underwent lateral reconstruction of the bile duct for defects secondary to choledocotomy for stone extraction or during dissection for Mirizzi syndrome. The defects measured 2 and 3 cm and occupied half of the bile duct circumference. The postoperative course was marked by low output biliary fistula resolved spontaneously. In one patient, the T tube was removed at 3 months after surgery and MRI at 9 months showed strictly normal aspect of the bile duct with normal liver function test. The second patient is going very well 2 months after surgery and the T tube is closed. Lateral reconstruction of the bile duct can be safely achieved with the vascularized round ligament. We will extend our indications to tubular reconstruction.

Anatomic variations in intrahepatic bile ducts in a north Indian population.

PubMed

Sharma, Vijay; Saraswat, Vivek Anand; Baijal, Sanjay Saran; Choudhuri, Gourdas

2008-07-01

In the present study, we described the anatomical variations in the branching patterns of intrahepatic bile ducts (IHD) and determined the frequency of each variation in north Indian patients. There are no data from India. The study group consisted of 253 consecutive patients (131 women) undergoing endoscopic retrograde cholangiograms for different indications. Anatomical variations in IHD were classified according to the branching pattern of the right anterior segmental duct (RASD) and the right posterior segmental duct (RPSD), presence or absence of first-order branch of left hepatic duct (LHD) and of an accessory hepatic duct. Anatomy of the IHD was typical in 52.9% of cases (n = 134), showing triple confluence in 11.46% (n = 29), anomalous drainage of the RPSD into the LHD in 18.2% (n = 46), anomalous drainage of the RPSD into the common hepatic duct (CHD) in 7.1% (n = 18), drainage of the right hepatic duct (RHD) into the cystic duct 0.4% (n = 1), presence of an accessory duct leading to the CHD or RHD in 4.7% (n = 12), individual drainage of the LHD into the RHD or CHD in 2.4% (n = 6), and unclassified or complex variations in 2.7% (n = 7). None had anomalous drainage of RPSD into the cystic duct. The branching pattern of IHD was atypical in 47% patients. The two most common variations were drainage of the RPSD into the LHD (18.2%) and triple confluence of the RASD, RPSD, and LHD (11.5%).

Iatrogenic bile duct strictures: a review of 22 cases.

PubMed

Ersumo, Tessema

2003-10-01

The incidence of iatrogenic bile duct strictures in Ethiopia appears to be increasing. Of 27 patients that sustained bile duct injuries at open cholecystectomy, admitted during May 1996 to December 2002, 22 cases of bile duct strictures are presented to evaluate outcome of treatment. The mean age was 40 years, 15 females. Twenty-one were referrals. The usual presenting features were biliary peritonitis and jaundice. The average time lapse between the original surgery and admission to hospital was eight months. About 73% had Bismuth grade III-IV strictures and all patients underwent Roux-en-Y hepatico-jejunostomy. Postoperatively, biliary-cutaneous fistula, recurrent ascending cholangitis and wound infection were observed frequently. The overall mortality rate was 13.6%. Bile duct injuries and strictures occur in young productive age groups. Prevention of the occurrence of bile duct injury and its progression to a devastating stricture reduces morbidity and mortality.

Patent vitellointestinal duct as paraumblical abcess: A rare presentation

PubMed Central

Rekhi, Harnam Singh; Mittal, Sushil; Singh, Gurtej; Rekhi, Balwinder Kaur; Dugg, Pankaj

2015-01-01

Introduction Umbilical and paraumblical abscess can occur in children with presenting complaint of discharge from umbilical region. However, patent vitello intestinal duct presenting as paraumblical abscess is rare phenomenon. Presentation of case One year old male child presented with complain of discharge from umbilical region since birth. Incision & drainage done twice thinking it to be paraumblical abscess. Discussion Vitellointestinal duct as abscess is rare presentation but it should be considered as a differential diagnosis of discharging umbilicus as management of abscess and patent duct are different. Conclusion Patent vitellointestinal duct can present as paraumbilical abscess, and it should be kept in differential diagnosis specifically in children. PMID:26301682

Method and apparatus for duct sealing using a clog-resistant insertable injector

DOEpatents

Wang, Duo; Modera, Mark P.

2010-12-14

A method for forming a duct access region through one side of a previously installed air duct, wherein the air duct has an air flow with an air flow direction by inserting an aerosol injector into a previously installed air duct through the access region. The aerosol injector includes a liquid tube having a liquid tube orifice for ejecting a liquid to be atomized; and a propellant cap. The method is accomplished by aligning the aerosol injector with the direction of air flow in the duct; activating an air flow within the duct; and spraying a sealant through the aerosol injector to seal the duct in the direction of the air flow.

Are Ducted Mini-Splits Worth It?

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

Winkler, Jonathan M; Maguire, Jeffrey B; Metzger, Cheryn E.

Ducted mini-split heat pumps are gaining popularity in some regions of the country due to their energy-efficient specifications and their ability to be hidden from sight. Although product and install costs are typically higher than the ductless mini-split heat pumps, this technology is well worth the premium for some homeowners who do not like to see an indoor unit in their living area. Due to the interest in this technology by local utilities and homeowners, the Bonneville Power Administration (BPA) has funded the Pacific Northwest National Laboratory (PNNL) and the National Renewable Energy Laboratory (NREL) to develop capabilities within themore » Building Energy Optimization (BEopt) tool to model ducted mini-split heat pumps. After the fundamental capabilities were added, energy-use results could be compared to other technologies that were already in BEopt, such as zonal electric resistance heat, central air source heat pumps, and ductless mini-split heat pumps. Each of these technologies was then compared using five prototype configurations in three different BPA heating zones to determine how the ducted mini-split technology would perform under different scenarios. The result of this project was a set of EnergyPlus models representing the various prototype configurations in each climate zone. Overall, the ducted mini-split heat pumps saved about 33-60% compared to zonal electric resistance heat (with window AC systems modeled in the summer). The results also showed that the ducted mini-split systems used about 4% more energy than the ductless mini-split systems, which saved about 37-64% compared to electric zonal heat (depending on the prototype and climate).« less

Detonation duct gas generator demonstration program

NASA Technical Reports Server (NTRS)

Wortman, Andrew; Brinlee, Gayl A.; Othmer, Peter; Whelan, Michael A.

1991-01-01

The feasibility of the generation of detonation waves moving periodically across high speed channel flow is experimentally demonstrated. Such waves are essential to the concept of compressing requirements and increasing the engine pressure compressor with the objective of reducing conventional compressor requirements and increasing the engine thermodynamic efficiency through isochoric energy addition. By generating transient transverse waves, rather than standing waves, shock wave losses are reduced by an order of magnitude. The ultimate objective is to use such detonation ducts downstream of a low pressure gas turbine compressor to produce a high overall pressure ratio thermodynamic cycle. A 4 foot long, 1 inch x 12 inch cross-section, detonation duct was operated in a blow-down mode using compressed air reservoirs. Liquid or vapor propane was injected through injectors or solenoid valves located in the plenum or the duct itself. Detonation waves were generated when the mixture was ignited by a row of spark plugs in the duct wall. Problems with fuel injection and mixing limited the air speeds to about Mach 0.5, frequencies to below 10 Hz, and measured pressure ratios of about 5 to 6. The feasibility of the gas dynamic compression was demonstrated and the critical problem areas were identified.

Liver and Bile Duct Cancer—Health Professional Version

Cancer.gov

Liver cancer includes two major types: hepatocellular carcinoma (HCC) and intrahepatic bile duct cancer, also known as cholangiocarcinoma. Find evidence-based information on liver and bile duct cancer treatment, causes and prevention, screening, research, genomics and statistics.

Large Eddy Simulation of Ducted Propulsors in Crashbac

NASA Astrophysics Data System (ADS)

Jang, Hyunchul; Mahesh, Krishnan

2008-11-01

Flow around a ducted marine propulsor is computed using the large eddy simulation methodology under crashback conditions. Crashback is an operating condition where a propulsor rotates in the reverse direction while the vessel moves in the forward direction. It is characterized by massive flow separation and highly unsteady propeller loads, which affect both blade life and maneuverability. The simulations are performed on unstructured grids using the algorithm developed by Mahesh at al. (2004, J. Comput. Phys 197). The flow is computed at the advance ratio J=-0.7 and Reynolds number Re=480,000 based on the propeller diameter. Average and RMS values of the unsteady loads such as thrust, torque, and side force on the blades and duct are compared to experiment. It is seen that even though effects of the duct on thrust and torque are not large enough, those on the side force are significant. The rms of side forces is much higher in the presence of the duct. Pressure distributions on blade surfaces and duct surface are examined and used to explain this effect. This work was supported by the United States Office of Naval Research under ONR Grant N00014-05-1-0003.

Glucagon-like peptide-2 protects impaired intestinal mucosal barriers in obstructive jaundice rats

PubMed Central

Chen, Jun; Dong, Jia-Tian; Li, Xiao-Jing; Gu, Ye; Cheng, Zhi-Jian; Cai, Yuan-Kun

2015-01-01

AIM: To observe the protective effect of glucagon-like peptide-2 (GLP-2) on the intestinal barrier of rats with obstructive jaundice and determine the possible mechanisms of action involved in the protective effect. METHODS: Thirty-six Sprague-Dawley rats were randomly divided into a sham operation group, an obstructive jaundice group, and a GLP-2 group; each group consisted of 12 rats. The GLP-2 group was treated with GLP-2 after the day of surgery, whereas the other two groups were treated with the same concentration of normal saline. Alanine aminotransferase (ALT), total bilirubin, and endotoxin levels were recorded at 1, 3, 7, 10 and 14 d. Furthermore, on the 14th day, body weight, the wet weight of the small intestine, pathological changes of the small intestine and the immunoglobulin A (IgA) expressed by plasma cells located in the small intestinal lamina propria were recorded for each group. RESULTS: In the rat model, jaundice was obvious, and the rats’ activity decreased 4-6 d post bile duct ligation. Compared with the sham operation group, the obstructive jaundice group displayed increased yellow staining of abdominal visceral serosa, decreased small intestine wet weight, thinning of the intestinal muscle layer and villi, villous atrophy, uneven height, fusion, partial villous epithelial cell shedding, substantial inflammatory cell infiltration and significantly reduced IgA expression. However, no significant gross changes were noted between the GLP-2 and sham groups. With time, the levels of ALT, endotoxin and bilirubin in the GLP-2 group were significantly increased compared with the sham group (P < 0.01). The increasing levels of the aforementioned markers were more significant in the obstructive jaundice group than in the GLP-2 group (P < 0.01). CONCLUSION: GLP-2 reduces intestinal mucosal injuries in obstructive jaundice rats, which might be attributed to increased intestinal IgA and reduced bilirubin and endotoxin. PMID:25593463

Imaging and radiological interventions in extra-hepatic portal vein obstruction

PubMed Central

Pargewar, Sudheer S; Desai, Saloni N; Rajesh, S; Singh, Vaibhav P; Arora, Ankur; Mukund, Amar

2016-01-01

Extrahepatic portal vein obstruction (EHPVO) is a primary vascular condition characterized by chronic long standing blockage and cavernous transformation of portal vein with or without additional involvement of intrahepatic branches, splenic or superior mesenteric vein. Patients generally present in childhood with multiple episodes of variceal bleed and EHPVO is the predominant cause of paediatric portal hypertension (PHT) in developing countries. It is a pre-hepatic type of PHT in which liver functions and morphology are preserved till late. Characteristic imaging findings include multiple parabiliary venous collaterals which form to bypass the obstructed portal vein with resultant changes in biliary tree termed portal biliopathy or portal cavernoma cholangiopathy. Ultrasound with Doppler, computed tomography, magnetic resonance cholangiography and magnetic resonance portovenography are non-invasive techniques which can provide a comprehensive analysis of degree and extent of EHPVO, collaterals and bile duct abnormalities. These can also be used to assess in surgical planning as well screening for shunt patency in post-operative patients. The multitude of changes and complications seen in EHPVO can be addressed by various radiological interventional procedures. The myriad of symptoms arising secondary to vascular, biliary, visceral and neurocognitive changes in EHPVO can be managed by various radiological interventions like transjugular intra-hepatic portosystemic shunt, percutaneous transhepatic biliary drainage, partial splenic embolization, balloon occluded retrograde obliteration of portosystemic shunt (PSS) and revision of PSS. PMID:27358683

Observationally constrained modeling of sound in curved ocean internal waves: examination of deep ducting and surface ducting at short range.

PubMed

Duda, Timothy F; Lin, Ying-Tsong; Reeder, D Benjamin

2011-09-01

A study of 400 Hz sound focusing and ducting effects in a packet of curved nonlinear internal waves in shallow water is presented. Sound propagation roughly along the crests of the waves is simulated with a three-dimensional parabolic equation computational code, and the results are compared to measured propagation along fixed 3 and 6 km source/receiver paths. The measurements were made on the shelf of the South China Sea northeast of Tung-Sha Island. Construction of the time-varying three-dimensional sound-speed fields used in the modeling simulations was guided by environmental data collected concurrently with the acoustic data. Computed three-dimensional propagation results compare well with field observations. The simulations allow identification of time-dependent sound forward scattering and ducting processes within the curved internal gravity waves. Strong acoustic intensity enhancement was observed during passage of high-amplitude nonlinear waves over the source/receiver paths, and is replicated in the model. The waves were typical of the region (35 m vertical displacement). Two types of ducting are found in the model, which occur asynchronously. One type is three-dimensional modal trapping in deep ducts within the wave crests (shallow thermocline zones). The second type is surface ducting within the wave troughs (deep thermocline zones). © 2011 Acoustical Society of America

Müllerian duct cyst: diagnosis with MR imaging.

PubMed

Thurnher, S; Hricak, H; Tanagho, E A

1988-07-01

The value of magnetic resonance (MR) imaging in diagnosing clinically suspected müllerian duct cysts was assessed in six patients. MR imaging correctly demonstrated the abnormality to be intraprostatic, consistent with the diagnosis of müllerian duct cysts in four patients, and allowed the diagnosis to be excluded in the other two. The demonstration of prostatic zonal anatomy, the ability to obtain direct images in all three orthogonal planes, and a large field of view make MR imaging valuable in the study of suspected müllerian duct cysts.

Transition duct with late injection in turbine system

DOEpatents

LeBegue, Jeffrey Scott; Pentecost, Ronnie Ray; Flanagan, James Scott; Kim, Won -Wook; McMahan, Kevin Weston

2015-09-15

A system for supplying an injection fluid to a combustor is disclosed. The system includes a transition duct comprising an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The passage defines a combustion chamber. The system further includes a tube providing fluid communication for the injection fluid to flow through the transition duct and into the combustion chamber.

Regeneratively cooled transition duct with transversely buffered impingement nozzles

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

Morrison, Jay A; Lee, Ching-Pang; Crawford, Michael E

2015-04-21

A cooling arrangement (56) having: a duct (30) configured to receive hot gases (16) from a combustor; and a flow sleeve (50) surrounding the duct and defining a cooling plenum (52) there between, wherein the flow sleeve is configured to form impingement cooling jets (70) emanating from dimples (82) in the flow sleeve effective to predominately cool the duct in an impingement cooling zone (60), and wherein the flow sleeve defines a convection cooling zone (64) effective to cool the duct solely via a cross-flow (76), the cross-flow comprising cooling fluid (72) exhausting from the impingement cooling zone. In themore » impingement cooling zone an undimpled portion (84) of the flow sleeve tapers away from the duct as the undimpled portion nears the convection cooling zone. The flow sleeve is configured to effect a greater velocity of the cross-flow in the convection cooling zone than in the impingement cooling zone.« less

Bile acid receptor TGR5 overexpression is associated with decreased intestinal mucosal injury and epithelial cell proliferation in obstructive jaundice.

PubMed

Ji, Chen-Guang; Xie, Xiao-Li; Yin, Jie; Qi, Wei; Chen, Lei; Bai, Yun; Wang, Na; Zhao, Dong-Qiang; Jiang, Xiao-Yu; Jiang, Hui-Qing

2017-04-01

Bile acids stimulate intestinal epithelial proliferation in vitro. We sought to investigate the role of the bile acid receptor TGR5 in the protection of intestinal epithelial proliferation in obstructive jaundice. Intestinal tissues and serum samples were obtained from patients with malignant obstructive jaundice and from bile duct ligation (BDL) rats. Intestinal permeability and morphological changes in the intestinal mucosa were observed. The functions of TGR5 in cell proliferation in intestinal epithelial injury were determined by overexpression or knockdown studies in Caco-2 and FHs 74 Int cells pretreated with lipopolysaccharide (LPS). Internal biliary drainage was superior to external biliary drainage in recovering intestinal permeability and mucosal histology in patients with obstructive jaundice. In BDL rats, feeding of chenodeoxycholic acid (CDCA) decreased intestinal mucosa injury. The levels of PCNA, a marker of proliferation, increased in response to CDCA feeding and were paralleled by elevated TGR5 expression. CDCA upregulated TGR5 expression and promoted proliferation in Caco-2 and FHs 74 Int cells pretreated with LPS. Overexpression of TGR5 resulted in increased PCNA, cell viability, EdU incorporation, and the proportion of cells in S phase, whereas knockdown of TGR5 had the opposite effect. Our data indicate that bile acids promote intestinal epithelial cell proliferation and decrease mucosal injury by upregulating TGR5 expression in obstructive jaundice. Copyright © 2016 Elsevier Inc. All rights reserved.

Heat Transfer in a Superelliptic Transition Duct

NASA Technical Reports Server (NTRS)

Poinsatte, Philip; Thurman, Douglas; Hippensteele, Steven

2008-01-01

Local heat transfer measurements were experimentally mapped using a transient liquid-crystal heat transfer technique on the surface of a circular-to-rectangular transition duct. The transition duct had a length-to-diameter ratio of 1.5 and an exit-plane aspect ratio of 3. The crosssectional geometry was defined by the equation of a superellipse. The cross-sectional area was the same at the inlet and exit but varied up to 15 percent higher through the transition. The duct was preheated to a uniform temperature (nominally 64 C) before allowing room temperature air to be suddenly drawn through it. As the surface cooled, the resulting isothermal contours on the duct surface were revealed using a surface coating of thermochromic liquid crystals that display distinctive colors at particular temperatures. A video record was made of the surface temperature and time data for all points on the duct surfaces during each test. Using this surface temperature-time data together with the temperature of the air flowing through the model and the initial temperature of the model wall, the heat transfer coefficient was calculated by employing the classic one-dimensional, semi-infinite wall heat transfer conduction model. Test results are reported for inlet diameter-based Reynolds numbers ranging from 0.4x106 to 2.4x106 and two grid-generated freestream turbulence intensities of about 1 percent, which is typical of wind tunnels, and up to 16 percent, which may be more typical of real engine conditions.

Changes in extrathymic T cells in the liver and intestinal intraepithelium in mice with obstructive jaundice.

PubMed

Ueno, Kimihiko; Ajiki, Tetsuo; Watanabe, Hisami; Abo, Toru; Takeyama, Yoshifumi; Onoyama, Hirohiko; Kuroda, Yoshikazu

2004-03-01

Recently, T cells were classified into two categories: intrathymic T cells (ITCs; thymus-derived T cells) and extrathymic T cells (ETCs). ETC, localized in the liver and intestinal intraepithelium (IE), play an important immunologic role in the suppressed condition of T-cell development in the thymus. Given the fact that complications of surgery in patients with obstructive jaundice are often related to immunosuppression in the gut-liver circulation, we attempted to investigate the changes in the proportion of ETCs in mice with obstructive jaundice. Three mice models were prepared ( n = 10 per group): sham group with simple laparotomy; ligation group with common bile duct ligation; deoxycholic acid (DCA) group with an oral intake of DCA as a model of the presence of bile salts in the gut lumen. In each model, total mononuclear cells (MNCs), ITCs in the thymus, and ETCs in the liver and IE were counted using monoclonal antibodies in conjunction with a two-color immunofluorescence test by flow cytometry. In the ligation group the number of MNCs was reduced in the thymus and IE, and only those in the IE recovered after oral intake of DCA. A decrease of ITCs in the thymus and the increase in ETCs in the liver and IE occurred simultaneously during the early phase of biliary obstruction. At day 7 after biliary obstruction, ETCs in the livers of the DCA and ligation groups decreased to nearly the level in the sham group. However, on day 7 the ETCs in the IE remained significantly higher in the DCA group than in the ligation group. These results suggested that ETCs can act in place of ITCs at an early phase of obstructive jaundice, and the presence of bile in the gut lumen may be associated with the consumption of ETCs in the IE, a reaction that may bring about improved immunoreactivity.

Outcomes of endonasal dacryocystorhinostomy without mucosal flap preservation.

PubMed

Hodgson, Nickisa; Bratton, Emily; Whipple, Katherine; Priel, Ayelet; Oh, Sang-Rog; Fante, Robert G; Kikkawa, Don O; Korn, Bobby S

2014-01-01

Dacryocystorhinostomy (DCR) is the standard procedure for the treatment of acquired nasolacrimal duct obstruction (NLDO) that can be performed through an external or endonasal approach. Both techniques create a fistula from the lacrimal sac into the nasal cavity via a bony osteotomy. Historically, external DCR has been considered the gold standard; however, recent reports suggest endonasal DCR is an effective alternative. There are numerous variations of endonasal DCR described in the literature that report variable success rates. The purpose of this study is to describe the approach and success rate with endonasal DCR in which nasal mucosa, bone, and lacrimal sac mucosa are sequentially removed. The authors retrospectively reviewed cases of endonasal DCR from 2004 to 2011 from 2 institutions (the University of California, San Diego, California, and the Fante Eye and Face Center in Denver, Colorado, U.S.A.). Patients with a history of epiphora and NLDO confirmed with punctal irrigation were included. Exclusion criteria were the presence of canalicular obstruction, history of orbital trauma, and prior DCR surgery. Success was defined as subjective relief of epiphora and confirmation of ostium patency with irrigation. A total of 324 patients (74 men, 250 women; mean age 59.3) encompassing 407 endonasal DCR cases were included in the study. The total case success rate was 92.2% with an average follow-up time of 91.5 days. Revision surgery was performed in 7 of the failed cases and resulted in success in 6 of these cases. Endonasal DCR is a simple and effective approach to surgically treat NLDO and offers success rates comparable with external DCR.

Photoneutron radiation field of ducts in barrier of 15 MV medical electron accelerators

NASA Astrophysics Data System (ADS)

Deng, Lei; Zhou, Ning; Chen, Yi-shui; Tu, Yu

2017-11-01

Shielding body of the high-energy medical electron accelerators is always penetrated by ducts, which would influence the shielding capability of local barrier. In order to quantitatively analyze the duct's impact on shielding of the photoneutron from 15 MV accelerators, the ambient dose equivalent rate and energy spectrum at the center of a typical duct and the external mouth of duct were calculated based on MCNP program for the first time. The results demonstrate that leakage neutrons at the external mouth of duct are mainly thermal neutron, and its dose rate is decreased with the increase of the intersection angle between duct and wall as well as the reduction of duct diameter. When a duct in a diameter no more than 30 cm penetrates the wall unidirectionally and the inclined Angle (θ) is 60°, neutron dose rate at the external mouth of duct could meet the requirements of protection. At last, according to the calculation results, some suggestions are proposed for the shielding design of ducts in walls.

Propolis reduces bacterial translocation and intestinal villus atrophy in experimental obstructive jaundice

PubMed Central

Sabuncuoglu, Mehmet Zafer; Kismet, Kemal; Kilicoglu, Sibel Serin; Kilicoglu, Bulent; Erel, Serap; Muratoglu, Sabahattin; Sunay, Asli Elif; Erdemli, Esra; Akkus, Mehmet Ali

2007-01-01

AIM: To investigate the effects of propolis on bacterial translocation and ultrastructure of intestinal morphology in experimental obstructive jaundice. METHODS: Thirty Wistar-Albino male rats were randomly divided into three groups, each including 10 animals: groupI, sham-operated; group II, ligation and division of the common bile duct (BDL); group III, BDL followed by oral supplementation of propolis 100 mg/kg per day. Liver, blood, spleen, mesenteric lymph nodes, and ileal samples were taken for microbiological, light and transmission electron microscopic examination on postoperative 7th d after sacrification. RESULTS: The mean number of villi per centimeter and mean mucosal height of the propolis group were significantly different in the BDL group (P = 0.001 and 0.012, respectively). The electron microscopic changes were also different between these groups. Sham and BDL + propolis groups had similar incidence of bacterial translocation (BT). The BDL group had significantly higher rates of BT as compared with sham and BDL + propolis groups. BT was predominantly detected in MLNs and the most commonly isolated bacteria was Escherichia coli. CONCLUSION: Propolis showed a significant protective effect on ileal mucosa and reduced bacterial translocation in the experimental obstructive jaundice model. Further studies should be carried out to explain the mechanisms of these effects. PMID:17876893

The statistical evaluation of duct tape end match as physical evidence

NASA Astrophysics Data System (ADS)

Chan, Ka Lok

Duct tapes are often submitted to crime laboratories as evidence associated with abductions, homicides, or construction of explosive devices. As a result, trace evidence examiners are often asked to analyze and compare commercial duct tapes so that they can establish possible evidentiary links. Duct tape end matches are believed to be the strongest association between exemplar and question samples because they are considered as evidence with unique individual characteristics. While end match analysis and comparison have long been undertaken by trace evidence examiners, there is a significant lack of scientific research for associating two or more segments of duct tapes. This study is designed to obtain statistical inferences on the uniqueness of duct tape tears. Three experiments were devised to compile the basis for a statistical assessment of the probability of duct tape end matches along with a proposed error rate. In one experiment, we conducted the equivalent of 10,000 end match examinations with an error rate of 0%. In the second experiment, we performed 2,704 end match examinations having 0% error rate. In the third experiment, using duct tape by an Elmendorf Tear tester, we conducted 576 end match examinations with an error rate of 0% and having all samples correctly associated. The results of this study indicate that end matches are distinguishable among a single roll of duct tape and between two different rolls of duct tape having very similar surface features and weave pattern.

Trypsin level in gallbladder bile and ductitis and width of the cystic duct.

PubMed

Vracko, J; Wiechel, K L

2000-01-01

The change from laparotomy to laparoscopy for cholecystectomy has raised the question of how to manage concomitant bile duct stones. The present-day interest--and controversy--has focused on a transcystic approach reported to be feasible in 66-96% of cases, but without explaining the necessary prerequisite: the widening of the cystic duct. The cystic duct, wide mainly in patients with bile duct stones, has been reported to be highly variable: from strictured to very wide. The present study aims at comparing the trypsin level in the gallbladder bile and the cystic duct morphology and width in patients with and without bile duct stones. A prospective series of 63 gallstone patients, 30 with and 33 without bile duct stones (controls), underwent cholecystectomy and bile duct clearance. The study includes the trypsin level in the gallbladder bile, the width and morphology of the cystic duct, and the size of the gallstones. The patients with bile duct stones had, in contrast to the controls, higher trypsin levels in the gallbladder bile (P < 0.001) and wider cystic ducts (P < 0.001) with more pronounced signs of chronic ductitis. The obtained results strongly suggest that the increased trypsin level, a sign of reflux of pancreatic juice, caused changes in the cystic duct that facilitate gallstone migration, which also ought to render a transcystic stone extraction feasible.

Design of power-plant installations pressure-loss characteristics of duct components

NASA Technical Reports Server (NTRS)

Henry, John R

1944-01-01

A correlation of what are believed to be the most reliable data available on duct components of aircraft power-plant installations is presented. The information is given in a convenient form and is offered as an aid in designing duct systems and, subject to certain qualifications, as a guide in estimating their performance. The design and performance data include those for straight ducts; simple bends of square, circular, and elliptical cross sections; compound bends; diverging and converging bends; vaned bends; diffusers; branch ducts; internal inlets; and an angular placement of heat exchangers. Examples are included to illustrate methods of applying these data in analyzing duct systems. (author)

Film condensation in a horizontal rectangular duct

NASA Technical Reports Server (NTRS)

Lu, Qing; Suryanarayana, N. V.

1993-01-01

Condensation heat transfer in a horizontal rectangular duct was experimentally and analytically investigated. To prevent the dripping of condensate on the film, the experiment was conducted inside a horizontal rectangular duct with vapor condensing only on the bottom cooled plate of the duct. R-113 and FC-72 (Fluorinert Electronic Fluid developed by the 3M Company) were used as the condensing fluids. The experimental program included measurements of film thickness, local and average heat transfer coefficients, wave length, wave speed, and a study of wave initiation. The measured film thickness was used to obtain the local heat transfer coefficient. The wave initiation was studied both with condensation and with an adiabatic air-liquid flow. The test sections used in both experiments were identical.

Intraductal Transanastomotic Stenting in Duct-to-Duct Biliary Reconstruction after Living-Donor Liver Transplantation: A Randomized Trial.

PubMed

Santosh Kumar, K Y; Mathew, Johns Shaji; Balakrishnan, Dinesh; Bharathan, Viju Kumar; Thankamony Amma, Binoj Sivasankara Pillai; Gopalakrishnan, Unnikrishnan; Narayana Menon, Ramachandran; Dhar, Puneet; Vayoth, Sudheer Othiyil; Sudhindran, Surendran

2017-12-01

Biliary complications continue to be the "Achilles heel" of living-donor liver transplantation (LDLT). The use of biliary stents in LDLT to reduce biliary complications is a controversial issue. We performed a randomized trial to study the impact of intraductal biliary stents on postoperative biliary complications after LDLT. Of the 94 LDLTs that were performed during a period of 16 months, ABO-incompatible transplants, left lobe grafts, 3 or more bile ducts on the graft, and those requiring bilioenteric drainage were excluded. Eligible patients were randomized to either a study arm (intraductal stent, n = 31) or a control arm (no stent, n = 33) by block randomization. Stratification was done, based on the number of ducts on the graft requiring anastomosis, into single (n = 20) or 2 ducts (n = 44). Ureteric stents of 3F to 5F placed across the biliary anastomosis and exiting into the duodenum for later endoscopic removal at 3 months were used. The primary end point was postoperative bile leak. Bile leak occurred in 15 of 64 (23.4%), the incidence was higher in the stented group compared with the control group (35.5% vs 12.1%; p = 0.03). Multiplicity of bile ducts and stenting were identified as risk factors for bile leak on multivariate analysis (p = 0.031 and p = 0.032). During a median follow-up of 2 years, biliary stricture developed in 9 patients (14.1%). Postoperative bile leak is a significant risk factor for the development of biliary stricture (p = 0.003). Intraductal transanastomotic biliary stenting and multiplicity of graft ducts were identified as independent risk factors for the development of postoperative biliary complications. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Measured Performance of a Varied Airflow Small-Diameter Duct System

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

Poerschke, Andrew

2017-03-01

This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measuremore » of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.« less

Measured Performance of a Varied Airflow Small-Diameter Duct System

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

Poerschke, Andrew

This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measuremore » of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.« less

Heat Transfer in Conical Corner and Short Superelliptical Transition Ducts

NASA Technical Reports Server (NTRS)

Poinsatte, Philip; Thurman, Douglas; Hippensteele, Steven

2008-01-01

Local surface heat transfer measurements were experimentally mapped using a transient liquid-crystal heat-transfer technique on the surface of two circular-to-rectangular transition ducts. One has a transition cross section defined by conical corners (Duct 1) and the other by an elliptical equation with changing coefficients (Duct 2). Duct 1 has a length-to-diameter ratio of 0.75 and an exit plane aspect ratio of 1.5. Duct 2 has a length-to-diameter ratio of 1.0 and an exit plane aspect ratio of 2.9. Test results are reported for various inlet-diameter-based Reynolds numbers ranging from 0.45 106 to 2.39 106 and two freestream turbulence intensities of about 1 percent, which is typical of wind tunnels, and up to 16 percent, which may be more typical of real engine conditions.

A Review of Double Common Bile Duct and Its Sequelae.

PubMed

Kolli, Sindhura; Etienne, Denzil; Reddy, Madhavi; Shahzad, Ghulamullah

2018-02-01

A double or accessory common bile duct (ACBD) is a rare congenital anomaly. We report the case of a 60-year-old American Asian male, who was found to have a double or duplicated common bile duct after being admitted for evaluation of a pancreatic mass. A duplicated bile duct has the same mucosa histologically as a single bile duct. However, the opening of a duplicated bile duct lacks a sphincter allowing retrograde flow of gut contents which results in a higher probability of intraductal calculus formation. On rare occasions, it can predispose to liver abscesses, pancreatitis, pancreatic cancer, gallbladder cancer, gastric cancer, and ampullary cancer depending on the location of the opening of the ACBD. We present an integrative review of the limited cases of ACBD with correlation to the current case and discussion regarding the aspects of diagnosis and management.

Sound attenuation of fiberglass lined ventilation ducts

NASA Astrophysics Data System (ADS)

Albright, Jacob

Sound attenuation is a crucial part of designing any HVAC system. Most ventilation systems are designed to be in areas occupied by one or more persons. If these systems do not adequately attenuate the sound of the supply fan, compressor, or any other source of sound, the affected area could be subject to an array of problems ranging from an annoying hum to a deafening howl. The goals of this project are to quantify the sound attenuation properties of fiberglass duct liner and to perform a regression analysis to develop equations to predict insertion loss values for both rectangular and round duct liners. The first goal was accomplished via insertion loss testing. The tests performed conformed to the ASTM E477 standard. Using the insertion loss test data, regression equations were developed to predict insertion loss values for rectangular ducts ranging in size from 12-in x 18-in to 48-in x 48-in in lengths ranging from 3ft to 30ft. Regression equations were also developed to predict insertion loss values for round ducts ranging in diameters from 12-in to 48-in in lengths ranging from 3ft to 30ft.

Flow in curved ducts of varying cross-section

NASA Astrophysics Data System (ADS)

Sotiropoulos, F.; Patel, V. C.

1992-07-01

Two numerical methods for solving the incompressible Navier-Stokes equations are compared with each other by applying them to calculate laminar and turbulent flows through curved ducts of regular cross-section. Detailed comparisons, between the computed solutions and experimental data, are carried out in order to validate the two methods and to identify their relative merits and disadvantages. Based on the conclusions of this comparative study a numerical method is developed for simulating viscous flows through curved ducts of varying cross-sections. The proposed method is capable of simulating the near-wall turbulence using fine computational meshes across the sublayer in conjunction with a two-layer k-epsilon model. Numerical solutions are obtained for: (1) a straight transition duct geometry, and (2) a hydroturbine draft-tube configuration at model scale Reynolds number for various inlet swirl intensities. The report also provides a detailed literature survey that summarizes all the experimental and computational work in the area of duct flows.

Stepwise approach to curative surgery using percutaneous transhepatic cholangiodrainage and portal vein embolization for severe bile duct injury during laparoscopic cholecystectomy: a case report.

PubMed

Honmyo, Naruhiko; Kuroda, Shintaro; Kobayashi, Tsuyoshi; Ishiyama, Kohei; Ide, Kentaro; Tahara, Hiroyuki; Ohira, Masahiro; Ohdan, Hideki

2016-12-01

Laparoscopic cholecystectomy (LC) has been recently adapted to acute cholecystitis. Major bile duct injury during LC, especially Strasberg-Bismuth classification type E, can be a critical problem sometimes requiring hepatectomy. Safety and definitive treatment without further morbidities, such as posthepatectomy liver failure, is required. Here, we report a case of severe bile duct injury treated with a stepwise approach using (99m)Tc-galactosyl human serum albumin ((99m)Tc-GSA) single-photon emission computed tomography (SPECT)/CT fusion imaging to accurately estimate liver function.A 52-year-old woman diagnosed with acute cholecystitis underwent LC at another hospital and was transferred to our university hospital for persistent bile leakage on postoperative day 20. She had no jaundice or infection, although an intraperitoneal drainage tube discharged approximately 500 ml of bile per day. Recorded operation procedure showed removal of the gallbladder with a part of the common bile duct due to its misidentification, and each of the hepatic ducts and right hepatic artery was injured. Abdominal enhanced CT revealed obstructive jaundice of the left liver and arterial shunt through the hilar plate to the right liver. Magnetic resonance cholangiopancreatography revealed type E4 or more advanced bile duct injury according to the Bismuth-Strasberg classification. We planned a stepwise approach using percutaneous transhepatic cholangiodrainage (PTCD) and portal vein embolization (PVE) for secure right hemihepatectomy and biliary-jejunum reconstruction and employed (99m)Tc-GSA SPECT/CT fusion imaging to estimate future remnant liver function. The left liver function rate had changed from 26.2 % on admission to 26.3 % after PTCD and 54.5 % after PVE, while the left liver volume rate was 33.8, 33.3, and 49.6 %, respectively. The increase of liver function was higher than that of volume (28.3 vs. 15.8 %). On postoperative day 63, the curative operation, right

Relationship Between Bile Duct Reconstruction and Complications in Living Donor Liver Transplantation.

PubMed

Miyagi, S; Kawagishi, N; Kashiwadate, T; Fujio, A; Tokodai, K; Hara, Y; Nakanishi, C; Kamei, T; Ohuchi, N; Satomi, S

2016-05-01

In living donor liver transplantation (LDLT), the recipient bile duct is thin and short. Bile duct complications often occur in LDLT, with persistent long-term adverse effects. Recently, we began to perform microsurgical reconstruction of the bile duct. The purpose of this study was to investigate the relationship between bile duct reconstruction methods and complications in LDLT. From 1991 to 2014, we performed 161 LDLTs (pediatric:adult = 90:71; left lobe:right lobe = 95:66). In this study, we retrospectively investigated the initial bile duct complications in LDLT and performed univariate and multivariate analyses to identify the independent risk factors for complications. The most frequent complication was biliary stricture (9.9%), followed by biliary leakage (6.8%). On univariate and multiple logistic regression analysis, the independent risk factors for biliary stricture were bile leakage (P = .0103) and recurrent cholangitis (P = .0077). However, there were no risk factors for biliary leakage on univariate analysis in our study. The reconstruction methods (hepaticojejunostomy or duct-to-duct anastomosis) and reconstruction technique (with or without microsurgery) were not risk factors for biliary stricture and leakage. In this study, the most frequent complication of LDLT was biliary stricture. The independent risk factors for biliary stricture were biliary leakage and recurrent cholangitis. Duct-to-duct anastomosis and microsurgical reconstruction of the bile duct were not risk factors for biliary stricture and leakage. Copyright © 2016 Elsevier Inc. All rights reserved.

Analysis of sound propagation in ducts using the wave envelope concept

NASA Technical Reports Server (NTRS)

Baumeister, K. J.

1974-01-01

A finite difference formulation is presented for sound propagation in a rectangular two-dimensional duct without steady flow for plane wave input. Before the difference equations are formulated, the governing Helmholtz equation is first transformed to a form whose solution does not oscillate along the length of the duct. This transformation reduces the required number of grid points by an order of magnitude, and the number of grid points becomes independent of the sound frequency. Physically, the transformed pressure represents the amplitude of the conventional sound wave. Example solutions are presented for sound propagation in a one-dimensional straight hard-wall duct and in a two-dimensional straight soft-wall duct without steady flow. The numerical solutions show evidence of the existence along the duct wall of a developing acoustic pressure diffusion boundary layer which is similar in nature to the conventional viscous flow boundary layer. In order to better illustrate this concept, the wave equation and boundary conditions are written such that the frequency no longer appears explicitly in them. The frequency effects in duct propagation can be visualized solely as an expansion and stretching of the suppressor duct.

14 CFR 25.1103 - Induction system ducts and air duct systems.

Code of Federal Regulations, 2013 CFR

2013-01-01

... between which relative motion could exist must have means for flexibility. (d) For turbine engine and... stage of the engine supercharger and of the auxiliary power unit compressor must have a drain to prevent... compartment to prevent hot gas reverse flow from burning through auxiliary power unit ducts and entering any...

Numerical and experimental investigation of conventional and un-conventional preswirl duct for VLCC

NASA Astrophysics Data System (ADS)

Shin, Hyun-Joon; Lee, Jong-Seung; Lee, Kang-Hoon; Han, Myung-Ryun; Hur, Eui-Beom; Shin, Sung-Chul

2013-09-01

This paper shows the study of preswirl duct as an effective energy saving devices that have been devised and reviewed to support the propeller performance, especially for the ship of VLCC with large block coefficients. From the bare hull wake measurements, typical upper/lower asymmetry of hull wake at the propeller disk was found. The 2 kinds of pre-swirl duct, Unconventional half circular duct and Conventional circular pre-swirl duct have been designed and reviewed to recover the loss of propeller running in that condition. The general function of the pre-swirl duct was set to work against this asymmetry of wake and generate pre-swirled flow into the propeller against the propeller rotating direction. The optimum self propulsion tests with various angle configurations were carried out and the best configuration was decided. Accordingly, cavitation test was carried out with best configuration of unconventional half circular duct. The blade surface and tip vortex cavitation behaved smoother when the duct was mounted. The hull pressure amplitudes reflected this difference, so the hull pressure amplitude with duct was smaller than that of without duct.

Endoscopic or surgical intervention for painful obstructive chronic pancreatitis.

PubMed

Ahmed Ali, Usama; Pahlplatz, Johanna M; Nealon, Wiliam H; van Goor, Harry; Gooszen, Hein G; Boermeester, Marja A

2015-03-19

Endoscopy and surgery are the treatment modalities of choice for patients with chronic pancreatitis and dilated pancreatic duct (obstructive chronic pancreatitis). Physicians face, without clear consensus, the choice between endoscopy or surgery for this group of patients. To assess and compare the effects and complications of surgical and endoscopic interventions in the management of pain for obstructive chronic pancreatitis. We searched the following databases in The Cochrane Library: CENTRAL (2014, Issue 2), the Cochrane Database of Systematic Reviews (2014, Issue 2), and DARE (2014, Issue 2). We also searched the following databases up to 25 March 2014: MEDLINE (from 1950), Embase (from 1980), and the Conference Proceedings Citation Index - Science (CPCI-S) (from 1990). We performed a cross-reference search. Two review authors independently performed the selection of trials. All randomised controlled trials (RCTs) of endoscopic or surgical interventions in obstructive chronic pancreatitis. We included trials comparing endoscopic versus surgical interventions as well as trials comparing either endoscopic or surgical interventions to conservative treatment (i.e. non-invasive treatment modalities). We included relevant trials irrespective of blinding, the number of participants randomised, and the language of the article. We used standard methodological procedures expected by The Cochrane Collaboration. Two authors independently extracted data from the articles. We evaluated the methodological quality of the included trials and requested additional information from study authors in the case of missing data. We identified three eligible trials. Two trials compared endoscopic intervention with surgical intervention and included a total of 111 participants: 55 in the endoscopic group and 56 in the surgical group. Compared with the endoscopic group, the surgical group had a higher proportion of participants with pain relief, both at middle/long-term follow-up (two to

Obstructive jaundice caused by pancreaticoduodenal artery aneurysms associated with celiac axis stenosis: case report and review of the literature.

PubMed

Yin, Tiansheng; Wan, Zhili; Chen, Hongwei; Mao, Xixian; Yi, Yayang; Li, Dewei

2015-07-01

Pancreaticoduodenal artery aneurysm (PDA) is quite rare, which accounts for only approximate 2% of all visceral aneurysms. Besides, PDA is usually related to celiac axis stenosis (CAS) and prone to rupture. Advanced imaging examination can facilitate the disclosure of such peripancreatic masses, but most of them were seldom diagnosed until they rupture because of the nonspecific symptoms. Secondary to PDA, obstructive jaundice is however an extremely rare manifestation. A case of an 84-year-old man is reported here, who suffered from severe jaundice caused by a ruptured PDA associated with CAS. In addition, this review collects and organizes PDAs with jaundice by applying a MEDLINE search and discusses the pathogenesis and therapeutic options of these aneurysms leading to external compression over the bile duct. Consequently, the formation of PDA with obstructive jaundice is based on the specific anatomy of pancreaticoduodenal arcades. When there is a retroperitoneal mass around the head of the pancreas associated with unexpected jaundice, PDA should be considered, for which early aggressive therapy is required. The case report and literature review suggest that PDA associated with obstructive jaundice may be treated successfully by single transcatheter arterial embolization (TAE) without auxiliary biliary drainage, whether it ruptures or not. Copyright © 2015 Elsevier Inc. All rights reserved.

A Double-Layered Covered Biliary Metal Stent for the Management of Unresectable Malignant Biliary Obstruction: A Multicenter Feasibility Study.

PubMed

Park, Jin-Seok; Jeong, Seok; Lee, Don Haeng; Moon, Jong Ho; Lee, Kyu Taek; Dong, Seok Ho

2016-11-15

The covered self-expandable metal stent (CMS) was developed to prevent tumor ingrowth-induced stent occlusion during the treatment of malignant biliary obstruction. However, complications such as cholecystitis, pancreatitis, and stent migration can occur after the endoscopic insertion of CMSs. The aim of the present study was to assess the efficacy and safety of a double-layered CMS (DCMS) for the management of malignant bile duct obstruction. DCMSs were endoscopically introduced into 59 patients with unresectable malignant extrahepatic biliary obstruction at four tertiary referral centers, and the patient medical records were retrospectively reviewed. Both the technical and functional success rates were 100%. Procedure-related complications including pancreatitis, cholangitis, stent migration, and liver abscess occurred in five patients (8.5%). The median follow-up period was 265 days (range, 31 to 752 days). Cumulative stent patency rates were 68.2% and 40.8% at 6 and 12 months, respectively. At the final follow-up, the rate of stent occlusion was 33.9% (20/59), and the median stent patency period was 276 days (range, 2 to 706 days). The clinical outcomes of DCMSs were comparable to the outcomes previously reported for CMSs with respect to stent patency period and complication rates.

Obstructed labour.

PubMed

Neilson, J P; Lavender, T; Quenby, S; Wray, S

2003-01-01

Obstructed labour is an important cause of maternal deaths in communities in which undernutrition in childhood is common resulting in small pelves in women, and in which there is no easy access to functioning health facilities with the capability of carrying out operative deliveries. Obstructed labour also causes significant maternal morbidity in the short term (notably infection) and long term (notably obstetric fistulas). Fetal death from asphyxia is also common. There are differences in the behaviour of the uterus during obstructed labour, depending on whether the woman has delivered previously. The pattern in primigravid women (typically diminishing contractility with risk of infection and fistula) may result from tissue acidosis, whereas in parous women, contractility may be maintained with the risk of uterine rupture. Ultimately, tackling the problem of obstructed labour will require universal adequate nutritional intake from childhood and the ability to access adequately equipped and staffed clinical facilities when problems arise in labour. These seem still rather distant aspirations. In the meantime, strategies should be implemented to encourage early recognition of prolonged labour and appropriate clinical responses. The sequelae of obstructed labour can be an enormous source of human misery and the prevention of obstetric fistulas, and skilled treatment if they do occur, are important priorities in regions where obstructed labour is still common.

SSME 3-D Turnaround Duct flow analysis - CFD predictions

NASA Technical Reports Server (NTRS)

Brankovic, Andreja; Stowers, Steven T.; Mcconnaughey, Paul

1988-01-01

CFD analysis is presently employed to obtain an improved flowfield for an individual flowpath in the case of the Space Shuttle Main Engine's High Pressure Fuel Turbopump Turn-Around Duct (TAD), which conducts the flow exiting from the gas turbines into the fuel bowl. It is demonstrated that the application of CFD to TAD flow analysis, giving attention to the duct's configuration and to the number, shape, and alignment of the diffuser struts, can enhance understanding of flow physics and result in improved duct design and performance.

A comparative study of modified transcanalicular diode laser dacryocystorhinostomy versus conventional transcanalicular diode laser dacryocystorhinostomy.

PubMed

Feijó, Eduardo Damous; Caixeta, Juliana Alves; de Souza Nery, Ana Carla; Limongi, Roberto Murillo; Matayoshi, Suzana

2017-08-01

External dacryocystorhinostomy (DCR) is the gold standard surgical technique for the treatment of primary acquired nasolacrimal duct obstruction (PANDO). However, new techniques such as endoscopic DCR and transcanalicular dacryocystorhinostomy (T-DCR) are being studied in an attempt to reduce surgical time, avoid external scarring and preserve the lacrimal pump while achieving the same efficacy. The purpose of this study was to compare the efficacy between conventional T-DCR and modified transcanalicular dacryocystorhinostomy (MT-DCR) in patients with PANDO. MT-DCR is performed to remove nasal mucosa prior to laser osteotomy. This is a comparative, prospective, interventionist and randomized study. Patients with PANDO were selected to undergo MT-DCR or T-DCR by blocked randomization. PANDO was diagnosed based on clinical presentation, dye disappearance test and dacryocystography. All of the procedures were performed by the same surgery team members. Anatomical success outcome was defined as positive lacrimal syringing and functional success outcome was defined as the absence or improvement of epiphora. A total of 44 surgical procedures were performed (22 MT-DCR and 22 T-DCR). In the case of MT-DCR, the anatomical and functional success rates after 12 months were 90 and 86%, respectively. After T-DCR, these rates were 77 and 72%, respectively (p = 0.162). MT-DCR and T-DCR are both safe and fast procedures with low morbidity and well-tolerated.

Endoscopic dacryocystorhinostomy with and without silicone intubation: 4 years retrospective study.

PubMed

Longari, F; Dehgani Mobaraki, P; Ricci, A L; Lapenna, R; Cagini, C; Ricci, G

2016-08-01

The objective of this study is to assess different outcomes between endoscopic dacryocystorhinostomy (En-DCR) with and without silicone intubation. We retrospectively analyzed 84 patients (89 procedures), suffering from chronic epiphora for primary acquired nasolacrimal duct obstruction, treated with En-DCR and divided into two groups depending on silicone stent intubation. The surgical outcomes were evaluated at 7 post-operative controls using Munk's score criteria. Functional success was defined as absence of epiphora, no further episodes of dacryocystitis, and a patent ostium after fluorescein irrigation. 45 En-DCR with stent and 44 En-DCR without stent were performed. Success rate after 18 months follow-up were, respectively, 82.2 % in the stent group and 88.6 % in the non-stent group (OR 0.59) with no statistical differences. The ostial size reduction has been reported in higher percentage in the stent group, mainly due to peristomal granuloma (OR 3.64), scar tissue formation (OR 2.25), and turbinoseptal synaechia (OR 1.76). The benefits of non-intubation are less patient discomfort, reduced surgical time and costs, simpler follow-up regimen and less intubation-associated complications. En-DCR without silicone stent intubation should be the first choice of procedure, stent intubation should be reserved in selected cases with poor local conditions pre and intra-operatively assessed.

Device for temporarily closing duct-formers in well completion apparatus

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

Zandmer, H.M.; Zandmer, S.M.

A duct-forming device is disclosed for use in a well completion apparatus of the kind, wherein a bore hole casing is positioned in a bore hole and duct-forming devices of alkali- and acid resistant metal-such as steel-are secured at spaced levels to the casing in alignment with holes machined in the casing wall. In accordance with the invention, a closure device is arranged within the duct-forming device which permits flow of predetermined amounts of liquid, such as acid, from the interior of the casing through the duct-forming device and into the producing formation, while gradually being moved by the liquidmore » into a position in which such fluid flow is prevented. After the fluid flow has been stopped by the closure device and when the formation pressure exceeds the pressure within the duct-forming device and the casing, fluid from the formation then forces the closure device toward and into the casing space to permit thereafter free flow of formation fluid into the duct-forming device and the casing or of pressurized treatment liquid from the casing into the formation. The inventive arrangement permits inter alia the establishment of a sufficient and substantially uniform feeding rate of treatment liquid, such as acid, from the casing into the producing formation through all the duct-formers in preparation for subsequent acidification or other treatments, such as sand fracking.« less

Laparoscopic bile duct injury: understanding the psychology and heuristics of the error.

PubMed

Dekker, Sidney W A; Hugh, Thomas B

2008-12-01

Bile duct injury is an important unsolved problem of laparoscopic cholecystectomy, occurring with unacceptable frequency even in the hands of experienced surgeons. This suggests that a systemic predisposition to the injury is intrinsic to cholecystectomy and indicates that an analysis of the psychology and heuristics of surgical decision-making in relation to duct identification may be a guide to prevention. Review of published reports on laparoscopic bile duct injury from 1997 to 2007 was carried out. An analysis was also carried out of the circumstances of the injuries in 49 patients who had transection of an extrahepatic bile duct and who were referred for reconstruction or were assessed in a medicolegal context. Special emphasis was placed on identifying the possible psychological aspects of duct misidentification. Review of published work showed an emphasis on the technical aspects of correct identification of the cystic duct, with few papers addressing the heuristics and psychology of surgical decision-making during cholecystectomy. Duct misidentification was the cause of injury in 42 out of the 49 reviewed patients (86%). The injury was not recognized at operation in 70% and delay in recognition persisted into the postoperative period in 57%. Underestimation of risk, cue ambiguity and visual misperception ('seeing what you believe') were important factors in misidentification. Delay in recognition of the injury is a feature consistent with cognitive fixation and plan continuation, which help construct and sustain the duct misidentification during the operation and beyond. Changing the 'culture' of cholecystectomy is probably the most effective strategy for preventing laparoscopic bile duct injury, especially if combined with new technical approaches and an understanding of the heuristics and psychology of the duct misidentification error. Training of surgeons for laparoscopic cholecystectomy should emphasize the need to be alert for cues that the incorrect

Mammary duct ectasia: a cause of bloody nipple discharge.

PubMed Central

Leung, Alexander K. C.; Kao, C. Pion

2004-01-01

We report a 13-year-old girl with bloody nipple discharge as a result of mammary duct ectasia. Our patient is the second reported case of mammary duct ectasia in a pubertal girl. Images Figure 1 PMID:15101674

Large-Eddy Simulation of Crashback in a Ducted Propulsor

NASA Astrophysics Data System (ADS)

Jang, Hyunchul; Mahesh, Krishnan

2011-11-01

Crashback is an operating condition to quickly stop a propelled vehicle, where the propeller is rotated in the reverse direction to yield negative thrust. The crashback condition is dominated by the interaction of free stream flow with strong reverse flow. Crashback causes highly unsteady loads and flow separation on blade surface. This study uses Large-Eddy Simulation to predict the highly unsteady flow field in crashback for a ducted propulsor. Thrust mostly arises from the blade surface, but most of side-force is generated from the duct surface. Both mean and RMS of pressure are much higher on inner surface of duct, especially near blade tips. This implies that side-force on the ducted propulsor is caused by the blade-duct interaction. Strong tip leakage flow is observed behind the suction side at the tip gap. The physical source of the tip leakage flow is seen to be the large pressure difference between pressure and suction sides. The conditional average during high amplitude event shows that the tip leakage flow and pressure difference are significantly higher. This work is supported by the United States Office of Naval Research under ONR Grant N00014-05-1-0003.

Analysis of obstruction site in obstructive sleep apnea syndrome patients by drug induced sleep endoscopy.

PubMed

Koo, Soo Kweon; Choi, Jang Won; Myung, Nam Suk; Lee, Hyoung Ju; Kim, Yang Jae; Kim, Young Joong

2013-01-01

We analyzed site, pattern and degree of obstruction in Korean male obstructive sleep apnea syndrome (OSAS) patients by drug-induced sleep endoscopy (DISE). We also investigated possible links between BMI, AHI and DISE findings. Sixty-nine male patients underwent DISE. DISE findings were reported using our classification system in which modified 'VOTE classification' - obstruction type, site of obstruction, degree of obstruction and anatomical site contributing obstruction - was reported. Associations were analyzed among the results of the polysomnography, patients' characteristics and DISE finding. Multilevel airway obstruction was found in 84.06% of patients and 15.94% had a unilevel obstruction. Among those with unilevel obstruction, 90.90% had retropalatal level obstruction and 9.10% had retrolingual level obstruction. Palate with lateral pharyngeal wall obstruction (49.28%) is the most common obstruction type of the retropalatal level and tongue with lateral pharyngeal wall (37.68%) is the most common obstruction type of the retrolingual level. Examining the relation between obstruction site according to body mass index (BMI) and severity of OSAS (apnea hypopnea index, AHI), the lateral pharyngeal wall had an increasing tendency associated with higher BMI and higher AHI. But the lateral pharyngeal wall of both levels was statistically significant associated with higher AHI. The majority of the Korean male OSAS patients have multilevel obstruction and according to BMI and AHI, the DISE findings indicate that the lateral pharyngeal wall is the most important anatomical site contributing to obstruction regardless of the level at which the obstruction lies. © 2013 Elsevier Inc. All rights reserved.

Biliary reconstruction in liver transplant patients with primary sclerosing cholangitis, duct-to-duct or Roux-en-Y?

PubMed

Shamsaeefar, Alireza; Shafiee, Mohammad; Nikeghbalian, Saman; Kazemi, Kourosh; Mansorian, Mohsenreza; Motazedian, Nasrin; Afshinnia, Farsad; Geramizadeh, Bita; Malekhosseini, Seyed Ali

2017-06-01

Roux-en-Y choledochojejunostomy and duct-to-duct (D-D) anastomosis are biliary reconstruction methods for liver transplantation. However, there is a controversy over which method produces better results. We have compared the outcome of D-D anastomosis vs. Roux-en-Y hepaticojejunostomy in patients with primary sclerosing cholangitis who had undergone liver transplant in Shiraz Organ Transplant Center. The medical records of 405 patients with primary sclerosing cholangitis (PSC) who had undergone liver transplant from 1996 to 2015 were reviewed. Patients were divided into two groups: Roux-en-Y group and D-D group. Morbidity, disease recurrence, and graft and patient survival rates were compared between the two groups. Total of 143 patients underwent a D-D biliary reconstruction, and 260 patients had a Roux-en-Y loop. Biliary complication involved 4.2% of patients from the D-D group, and 3.9% from the Roux-en-Y group (P=. 863). Actuarial 1-, 3-, and 5-year patient survival for D-D and Roux-en-Y group was 92%, 85%, and 74%; and 87%, 83%, and 79%, respectively (P=.384). The corresponding 1-, 3-, and 5-year probability of biliary complication was 97%, 95%, and 92%; and 98%, 97%, and 94%, respectively (P=.61). Duct-to-duct biliary reconstruction in liver transplantation for selected patients with PSC is a good alternative instead of Roux-en-Y biliary reconstruction. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Bile Duct Cancer (Cholangiocarcinoma) Symptoms, Tests, Prognosis, and Stages (PDQ®)—Patient Version

Cancer.gov

Bile duct cancer, or cholangiocarcinoma, is rare. Bile ducts are tubes that carry bile between the liver, gallbladder, and small intestine. Bile duct cancer can occur in the intrahepatic, perihilar (Klatskin tumor), or distal extrahepatic area. Learn about tests to diagnose and the stages of bile duct cancer.

Designing insulation for cryogenic ducts

NASA Astrophysics Data System (ADS)

Love, C. C.

1984-03-01

It is pointed out that the great temperature difference between the outside of a cryogenic duct and the liquified gas it carries can cause a high heat input unless blocked by a high thermal resistance. High thermal resistance for lines needing maximum insulation is provided by metal vacuum jackets. Low-density foam is satisfactory in cases in which higher heat input can be tolerated. Attention is given to the heat transfer through a duct vacuum jacket, the calculation of heat input and the exterior surface's steady-state temperature for various thicknesses of insulation, the calculation of the heat transfer through gimbal jackets, and design specifications regarding the allowable pressure rise in the jacket's annular space.

Modified duval procedure for small-duct chronic pancreatitis without head dominance.

PubMed

Oida, Takatsugu; Aramaki, Osamu; Kano, Hisao; Mimatsu, Kenji; Kawasaki, Atsushi; Kuboi, Youichi; Fukino, Nobutada; Kida, Kazutoshi; Amano, Sadao

2011-01-01

In the case of small-duct chronic pancreatitis, surgery for pain relief is broadly divided into resection and drainage procedures. These procedures should be selected according to the location of dominant lesion, diameter of the pancreatic duct and extent of the disease. The appropriate procedure for the treatment of small-duct chronic pancreatitis, especially small-duct chronic pancreatitis without head dominance, remains controversial. We developed the modified Duval procedure for the treatment of small-duct chronic pancreatitis without head dominance and determined the efficacy of this procedure. We retrospectively studied 14 patients who underwent surgical drainage with or without pancreatic resection for chronic pancreatitis with small pancreatic duct (<7mm) without head dominance. These patients were divided into 2 groups; the modified Puestow procedure group and the modified Duval procedure group. No complications occurred in the modified Duval group. In the modified Puestow procedure group, complete and partial pain relief were observed in 62.5%, and 37.5% of patients respectively. In contrast, complete pain relief was observed in all the patients in the modified Duval procedure group. Our modified Duval procedure is useful and should be considered the appropriate surgical technique for the treatment of small-duct chronic pancreatitis without head dominance.

The Primary Duct of Bothrops jararaca Glandular Apparatus Secretes Toxins

PubMed Central

Sakai, Fernanda; Portes-Junior, José Antonio; Godoy Viana, Luciana; Mendes Carneiro, Sylvia; Perales, Jonas; Yamanouye, Norma

2018-01-01

Despite numerous studies concerning morphology and venom production and secretion in the main venom gland (and some data on the accessory gland) of the venom glandular apparatus of Viperidae snakes, the primary duct has been overlooked. We characterized the primary duct of the Bothrops jararaca snake by morphological analysis, immunohistochemistry and proteomics. The duct has a pseudostratified epithelium with secretory columnar cells with vesicles of various electrondensities, as well as mitochondria-rich, dark, basal, and horizontal cells. Morphological analysis, at different periods after venom extraction, showed that the primary duct has a long cycle of synthesis and secretion, as do the main venom and accessory glands; however, the duct has a mixed mode venom storage, both in the lumen and in secretory vesicles. Mouse anti-B. jararaca venom serum strongly stained the primary duct’s epithelium. Subsequent proteomic analysis revealed the synthesis of venom toxins—mainly C-type lectin/C-type lectin-like proteins. We propose that the primary duct’s toxin synthesis products complement the final venom bolus. Finally, we hypothesize that the primary duct and the accessory gland (components of the venom glandular apparatus) are part of the evolutionary path from a salivary gland towards the main venom gland. PMID:29533989

Sound Radiation from a Supersonic Jet Passing Through a Partially Open Exhaust Duct

NASA Technical Reports Server (NTRS)

Kandula, Max

2011-01-01

The radiation of sound from a perfectly expanded Mach 2.5 cold supersonic jet of 25.4 mm exit diameter flowing through a partially open rigid-walled duct with an upstream i-deflector has been studied experimentally. In the experiments, the nozzle is mounted vertically, with the nozzle exit plane at a height of 73 jet diameters above ground level. Relative to the nozzle exit plane (NEP), the location of the duct inlet is varied at 10, 5, and -1 jet diameters. Far-field sound pressure levels were obtained at 54 jet diameters above ground with the aid of acoustic sensors equally spaced around a circular arc of radius equal to 80 jet diameters from the jet axis. Data on the jet acoustic field for the partially open duct were obtained and compared with those with a free jet and with a closed duct. The results suggest that for the partially open duct the overall sound pressure level (OASPL) decreases as the distance between the NEP and the duct inlet plane decreases, while the opposite trend is observed for the closed duct. It is also concluded that the observed peak frequency in the partially open duct increases above the free jet value as the angle from the duct axis is increased, and as the duct inlet plane becomes closer to the NEP.

Evaluation of several non-reflecting computational boundary conditions for duct acoustics

NASA Technical Reports Server (NTRS)

Watson, Willie R.; Zorumski, William E.; Hodge, Steve L.

1994-01-01

Several non-reflecting computational boundary conditions that meet certain criteria and have potential applications to duct acoustics are evaluated for their effectiveness. The same interior solution scheme, grid, and order of approximation are used to evaluate each condition. Sparse matrix solution techniques are applied to solve the matrix equation resulting from the discretization. Modal series solutions for the sound attenuation in an infinite duct are used to evaluate the accuracy of each non-reflecting boundary conditions. The evaluations are performed for sound propagation in a softwall duct, for several sources, sound frequencies, and duct lengths. It is shown that a recently developed nonlocal boundary condition leads to sound attenuation predictions considerably more accurate for short ducts. This leads to a substantial reduction in the number of grid points when compared to other non-reflecting conditions.

Asymptomatic T-tube remnant in common bile duct.

PubMed

Rozario, A; Thomas, P G; Pais, A; Ravindra, K V; Rao, V

1999-01-01

A 46-year-old lady presented with itching, five years after a primary common bile duct repair following cholecystectomy. Prior to this she underwent an interno-external biliary drainage. At laparotomy the horizontal limb of a T-tube was found in the common hepatic duct. Eleven months after a Roux loop hepatico-jejunostomy she is asymptomatic.

Acoustic theory of axisymmetric multisectioned ducts. [reduction of turbofan engine noise

NASA Technical Reports Server (NTRS)

Zorumski, W. E.

1974-01-01

Equations are developed for the acoustic field in a duct system which is made up of a number of connected circular and annular ducts. These equations are suitable for finding the acoustic field inside of and radiated from an aircraft turbofan engine. Acoustic modes are used as generalized coordinates in order to develop a set of matrix equations for the acoustic field. Equations for these modes are given for circular and annular ducts with uniform flow. Modal source equations are derived for point acoustic sources. General equations for mode transmission and reflection are developed and detailed equations are derived for ducts with multiple sections of acoustic treatment and for ducts with circumferential splitter rings. The general theory is applied to the special case of a uniform area circular duct with multisection liners and it is shown that the mode reflection effects are proportional to differences of the acoustic admittances of adjacent liners. A numerical example is given which shows that multisection liners may provide greater noise suppression than uniform liners.

Carcinosarcoma of the Extrahepatic Bile Duct Presenting with Stone-like Radiological Findings.

PubMed

Kumei, Shinsuke; Onishi, Yutaka; Ogura, Takeshi; Kusumoto, Chosei; Matsuno, Yasuko; Nishigami, Takashi; Maeda, Mitsuo; Harada, Masaru

2015-01-01

A 73-year-old woman was referred to our hospital due to epigastralgia and jaundice. The radiological findings showed a stone-like tumor in the extrahepatic bile duct. The patient was initially thought to have adenocarcinoma of the bile duct based on the findings of a pathological examination of the bile duct biopsy specimen and underwent pancreaticoduodenectomy; the final diagnosis of the lesion was so-called carcinosarcoma of the extrahepatic bile duct. She died of liver metastasis six months after the surgery. This case suggests that surgical resection is not adequate for achieving a radical cure, and the optimal treatment for extrahepatic bile duct carcinosarcoma should be established immediately.

Active noise control in a duct to cancel broadband noise

NASA Astrophysics Data System (ADS)

Chen, Kuan-Chun; Chang, Cheng-Yuan; Kuo, Sen M.

2017-09-01

The paper presents cancelling duct noises by using the active noise control (ANC) techniques. We use the single channel feed forward algorithm with feedback neutralization to realize ANC. Several kinds of ducts noises including tonal noises, sweep tonal signals, and white noise had investigated. Experimental results show that the proposed ANC system can cancel these noises in a PVC duct very well. The noise reduction of white noise can be up to 20 dB.

A quantitative analysis of electrolyte exchange in the salivary duct

PubMed Central

Catalán, Marcelo A.; Melvin, James E.; Yule, David I.; Crampin, Edmund J.; Sneyd, James

2012-01-01

A healthy salivary gland secretes saliva in two stages. First, acinar cells generate primary saliva, a plasma-like, isotonic fluid high in Na+ and Cl−. In the second stage, the ducts exchange Na+ and Cl− for K+ and HCO3−, producing a hypotonic final saliva with no apparent loss in volume. We have developed a tool that aims to understand how the ducts achieve this electrolyte exchange while maintaining the same volume. This tool is part of a larger multiscale model of the salivary gland and can be used at the duct or gland level to investigate the effects of genetic and chemical alterations. In this study, we construct a radially symmetric mathematical model of the mouse salivary gland duct, representing the lumen, the cell, and the interstitium. For a given flow and primary saliva composition, we predict the potential differences and the luminal and cytosolic concentrations along a duct. Our model accounts well for experimental data obtained in wild-type animals as well as knockouts and chemical inhibitors. Additionally, the luminal membrane potential of the duct cells is predicted to be very depolarized compared with acinar cells. We investigate the effects of an electrogenic vs. electroneutral anion exchanger in the luminal membrane on concentration and the potential difference across the luminal membrane as well as how impairing the cystic fibrosis transmembrane conductance regulator channel affects other ion transporting mechanisms. Our model suggests the electrogenicity of the anion exchanger has little effect in the submandibular duct. PMID:22899825

HAARP-Induced Ionospheric Ducts

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

Milikh, Gennady; Vartanyan, Aram

2011-01-04

It is well known that strong electron heating by a powerful HF-facility can lead to the formation of electron and ion density perturbations that stretch along the magnetic field line. Those density perturbations can serve as ducts for ELF waves, both of natural and artificial origin. This paper presents observations of the plasma density perturbations caused by the HF-heating of the ionosphere by the HAARP facility. The low orbit satellite DEMETER was used as a diagnostic tool to measure the electron and ion temperature and density along the satellite orbit overflying close to the magnetic zenith of the HF-heater. Thosemore » observations will be then checked against the theoretical model of duct formation due to HF-heating of the ionosphere. The model is based on the modified SAMI2 code, and is validated by comparison with well documented experiments.« less

Duct Liner Optimization for Turbomachinery Noise Sources

DTIC Science & Technology

1975-11-01

AD-A279 441lIIIflhIh* NASA TECHNICAL NASA TMA X-72789 MEMORANDUM oo £ 00 r-:. DUCT LINER OPTIMIZATION FOR TURBOMACHINERY w NOISE SOURCES By Harold C...Recipient’s r.atalog No. NASA TM X-72789! 4 Title diid Subtitle 5. Rewrt Date Duct Liner Optimization for Turbomachinery Noise Sources November 1975...profiles is combined wit., a numerical minimization algorithm to predict optimal liner configurations having one, two, and three sections. Source models

Acoustic power balance in lined ducts

NASA Technical Reports Server (NTRS)

Eversman, W.

1979-01-01

It is shown that the two common definitions of acoustic energy density and intensity in uniform unlined ducts carrying uniform flow are compatible to the extent that both energy densities can be used in an appropriate variational principle to derive the convected wave equation. When the duct walls are lined both energy densities must be modified to account for the wall energy density. This results in a new energy conservation equation which utilizes a modified definition of axial power and accounts for wall dissipation. Computations in specific cases demonstrate the validity of the modified acoustic energy relation.

Laser velocimeter and total pressure measurements in circular-to-rectangular transition ducts

NASA Technical Reports Server (NTRS)

Patrick, William P.; Mccormick, Duane C.

1988-01-01

A comprehensive set of total pressure and three-component laser velocimetry (LV) data were obtained within two circular-to-rectangular transition ducts at low subsonic speeds. This set of reference data was acquired for use in identifying secondary flow mechanisms and for assessing the accuracy of computational procedures for calculating such flows. Data were obtained at the inlet and exit planes of an aspect ratio three duct having a length-to-diameter ratio of one (AR310) and an aspect ratio six duct having a length-to-diameter ratio of three (AR630). Each duct was unseparated throughout its transition section. It is therefore concluded that secondary flows can play an important part in the fluid dynamics of transition ducts and needs to be addressed in computational analysis. The strength of the secondary flows depends on both the aspect ratio and relative axial duct length.

Experimental study of sound propagation in a flexible duct

PubMed

Huang; Choy; So; Chong

2000-08-01

Propagation of sound in a flexible duct is investigated both theoretically and experimentally. Strong coupling of sound and flexural waves on the duct wall is found when the wall-to-air mass ratio is of the order of unity. The axial phase speed of sound approaches the in vacuo speed of flexural waves (subsonic in this case) at low frequencies. However, a speed higher than the isentropic sound speed in free space (340 m/s) is found beyond a critical frequency which is a function of the mass ratio. Experiments using a duct with a finite section of tensioned membrane are compared with the propagating modes pertaining to the infinite membrane model. Satisfactory quantitative agreement is obtained and the measured phase speed ranges from 8.3 to 1348 m/s. In the moderate frequency range, the theory predicts high spatial damping rate for the subsonic waves, which is consistent with the experimental observation that subsonic waves become increasingly undetectable as the frequency increases. Substantial sound reflection is observed at the interface between the rigid and the flexible segments of the duct without cross-section discontinuity, which, together with the high spatial damping, could form a basis for passive control of low-frequency duct noise.

Mucocele of the cystic duct remnant after orthotopic liver transplant: a problem revisited.

PubMed

Chatterjee, Suvadip; Das, Debasish; Hudson, Mark; Bassendine, Margaret Fiona; Scott, John; Oppong, Kofi Ernest; Sen, Gourab; French, Jeremy J

2011-06-01

Mucocele of the cystic duct remnant is an uncommon hepatobiliary complication of a liver transplant. Current practice usually involves either excising the cystic duct, or incorporating the distal end of the transected cystic duct into the suture line of the biliary anastomosis to ensure drainage. We report a patient who developed cystic duct remnant mucocele after the latter approach was adopted. We believe that this is likely related to delayed anastomotic stricturing, which prevented draining from the remnant cystic duct. We also discuss the incidence, pathology, investigations, and treatment of this condition.

Duct flow nonuniformities: Effect of struts in SSME HGM II(+)

NASA Technical Reports Server (NTRS)

Burke, Roger

1988-01-01

A numerical study, using the INS3D flow solver, of laminar and turbulent flow around a two dimensional strut, and three dimensional flow around a strut in an annulus is presented. A multi-block procedure was used to calculate two dimensional laminar flow around two struts in parallel, with each strut represented by one computational block. Single block calculations were performed for turbulent flow around a two dimensional strut, using a Baldwin-Lomax turbulence model to parameterize the turbulent shear stresses. A modified Baldwin-Lomax model was applied to the case of a three dimensional strut in an annulus. The results displayed the essential features of wing-body flows, including the presence of a horseshoe vortex system at the junction of the strut and the lower annulus surface. A similar system was observed at the upper annulus surface. The test geometries discussed were useful in developing the capability to perform multiblock calculations, and to simulate turbulent flow around obstructions located between curved walls. Both of these skills will be necessary to model the three dimensional flow in the strut assembly of the SSME. Work is now in progress on performing a three dimensional two block turbulent calculation of the flow in the turnaround duct (TAD) and strut/fuel bowl juncture region.

Observed characteristics of atmospheric ducts over the South China Sea in autumn

NASA Astrophysics Data System (ADS)

Cheng, Yinhe; Zhou, Shengqi; Wang, Dongxiao; Lu, Yuanzheng; Huang, Ke; Yao, Jinglong; You, Xiaobao

2016-05-01

The observed characteristics of lower atmospheric ducts over the South China Sea (SCS) were analyzed based on Global Position Systerm (GPS) radiosonde data collected four times daily during autumn open cruises from 2006 to 2012. Duct occurrence, thickness, and strength over the SCS were about 40%, 150-m thick, and 8 M units, respectively, which were larger than during the summer monsoon period. Most ducts occurred at heights <1 500 m and these ducts easily trap electromagnetic wave clusters with wavelengths <2 m. Diurnal variation of the SCS ducts appeared evident. They occurred more often at midnight at higher altitudes (about 1 100 m), with a thickest layer of about 145 m and less frequently during the evening at lower altitudes (about 800 m), with a thinnest layer of about 125 m. Moreover, ducts during the daytime at a mean height of about 900 m, with the greatest strength of about 10 M units. Furthermore, all duct variables observed over the SCS in autumn decreased from north to south. These findings are useful not only in the design of radar and communication systems, but also for evaluating possible effects of anomalous propagation on meteorological radar and military applications.

Heat Transfer Computations of Internal Duct Flows With Combined Hydraulic and Thermal Developing Length

NASA Technical Reports Server (NTRS)

Wang, C. R.; Towne, C. E.; Hippensteele, S. A.; Poinsatte, P. E.

1997-01-01

This study investigated the Navier-Stokes computations of the surface heat transfer coefficients of a transition duct flow. A transition duct from an axisymmetric cross section to a non-axisymmetric cross section, is usually used to connect the turbine exit to the nozzle. As the gas turbine inlet temperature increases, the transition duct is subjected to the high temperature at the gas turbine exit. The transition duct flow has combined development of hydraulic and thermal entry length. The design of the transition duct required accurate surface heat transfer coefficients. The Navier-Stokes computational method could be used to predict the surface heat transfer coefficients of a transition duct flow. The Proteus three-dimensional Navier-Stokes numerical computational code was used in this study. The code was first studied for the computations of the turbulent developing flow properties within a circular duct and a square duct. The code was then used to compute the turbulent flow properties of a transition duct flow. The computational results of the surface pressure, the skin friction factor, and the surface heat transfer coefficient were described and compared with their values obtained from theoretical analyses or experiments. The comparison showed that the Navier-Stokes computation could predict approximately the surface heat transfer coefficients of a transition duct flow.

An unsteady Euler scheme for the analysis of ducted propellers

NASA Technical Reports Server (NTRS)

Srivastava, R.

1992-01-01

An efficient unsteady solution procedure has been developed for analyzing inviscid unsteady flow past ducted propeller configurations. This scheme is first order accurate in time and second order accurate in space. The solution procedure has been applied to a ducted propeller consisting of an 8-bladed SR7 propeller with a duct of NACA 0003 airfoil cross section around it, operating in a steady axisymmetric flowfield. The variation of elemental blade loading with radius, compares well with other published numerical results.

Functional anatomy and immunological interactions of ocular surface and adnexa.

PubMed

Paulsen, Friedrich

2008-01-01

This chapter gives an overview about the structures and physiology of the ocular surface and its adnexa and focuses in a second part on the possible meaning of eye-associated lymphoid tissue (EALT) in a context with the development of dry eye. Sections deal with (1) anatomy of the ocular surface, lacrimal gland, eyelid and nasolacrimal ducts. (2) The meaning and importance of the lacrimal functional unit and the function of the mucosal innate immune system are briefly summarized. (3) Finally, the occurrence and the possible function of EALT is discussed with regard to tolerance induction and dry eye. The epithelial surface of the eye and its specialized glandular infoldings produce the components of the tear film, which include water, protective antimicrobials, cytokines, lipids as well as mucins and trefoil factor family (TFF) peptides. Antimicrobials, mucins and TFF peptides perform a number of essential functions which, collectively, provide protection of the ocular surface. Their production changes in cases of dry eye. The development of EALT is a common feature frequently occurring in symptomatically normal conjunctiva and nasolacrimal ducts. The production of antimicrobials, mucins and TFF peptides can be linked with cell signaling, tear film rheology, and antimicrobial defense at the ocular surface. Changes in the production of such peptides and proteins in cases of dry eye support the assumption that these peptides and proteins are involved in the pathophysiological events that occur at the ocular surface and lacrimal apparatus. Whether special types of bacteria, viruses, or other factors, e.g., immune deviation, are responsible for the development of EALT in humans requires further investigation in prospective and experimental studies.

Excluded segmental duct bile leakage: the case for bilio-enteric anastomosis.

PubMed

Patrono, Damiano; Tandoi, Francesco; Romagnoli, Renato; Salizzoni, Mauro

2014-06-01

Excluded segmental duct bile leak is the rarest type of post-hepatectomy bile leak and presents unique diagnostic and management features. Classical management strategies invariably entail a significant loss of functioning hepatic parenchyma. The aim of this study is to report a new liver-sparing technique to handle excluded segmental duct bile leakage. Two cases of excluded segmental duct bile leak occurring after major hepatic resection were managed by a Roux-en-Y hepatico-jejunostomy on the excluded segmental duct, avoiding the sacrifice of the liver parenchyma origin of the fistula. In both cases, classical management strategies would have led to the functional loss of roughly 50 % of the liver remnant. Diagnostic and management implications are thoroughly discussed. Both cases had an uneventful postoperative course. The timing of repair was associated with a different outcome: the patient who underwent surgical repair in the acute phase developed no long-term complications, whereas the patient who underwent delayed repair developed a late stenosis requiring percutaneous dilatation. Roux-en-Y hepatico-jejunostomy on the excluded bile duct is a valuable technique in selected cases of excluded segmental duct bile leakage.

[ENDOSONOGRAPHY IN THE DIFFERENTIAL DIAGNOSIS OF THE COMMON BILE DUCT STENOSIS].

PubMed

Solodinina, E N; Starkov, Y G; Shumkin, L V

2015-01-01

The article states the results of examination and treatment of 57 patients with stenosis of the common bile duct of various genesis. The main aim of the work is criteria definition and evaluation of diagnostic significance of endosonography in the differential diagnosis of benign and malignant common bile duct stenosis. The paper presents a methodology of endoscopic ultrasound and basic criteria for the differential diagnosis of tumors and other lesions of the extrahepatic bile ducts. A comparative analysis of endosonography, ultrasound, CT, MRCP was conducted. The sensitivity of endosonography in determining the nature of the common bile duct stenosis was 97.7%, a specificity 100% and accuracy 98.2%, which is superior to other methods of radiological diagnosis. In comprehensive surgical centers endosonography should be used as a method of specifying the final diagnosis to determine the nature of the common bile duct stenosis, particularly at low constriction location.

Locating and Quantifying Broadband Fan Sources Using In-Duct Microphones

NASA Technical Reports Server (NTRS)

Dougherty, Robert P.; Walker, Bruce E.; Sutliff, Daniel L.

2010-01-01

In-duct beamforming techniques have been developed for locating broadband noise sources on a low-speed fan and quantifying the acoustic power in the inlet and aft fan ducts. The NASA Glenn Research Center's Advanced Noise Control Fan was used as a test bed. Several of the blades were modified to provide a broadband source to evaluate the efficacy of the in-duct beamforming technique. Phased arrays consisting of rings and line arrays of microphones were employed. For the imaging, the data were mathematically resampled in the frame of reference of the rotating fan. For both the imaging and power measurement steps, array steering vectors were computed using annular duct modal expansions, selected subsets of the cross spectral matrix elements were used, and the DAMAS and CLEAN-SC deconvolution algorithms were applied.

Complicated bile duct stones

PubMed Central

Roy, Ashwin; Martin, Derrick

2013-01-01

Common bile duct stones (CBDSs) are solid deposits that can either form within the gallbladder or migrate to the common bile duct (CBD), or form de novo in the biliary tree. In the USA around 15% of the population have gallstones and of these, 3% present with symptoms annually. Because of this, there have been major advancements in the management of gallstones and related conditions. Management is based on the patient's risk profile; young and healthy patients are likely to be recommended for surgery and elderly patients with comorbidities are usually recommended for endoscopic procedures. Imaging of gallstones has advanced in the last 30 years with endoscopic retrograde cholangiopancreatography evolving from a diagnostic to a therapeutic procedure in removing CBDSs. We present a complicated case of a patient with a CBDS and periampullary diverticulum and discuss the techniques used to diagnose and remove the stone from the biliary system. PMID:23946532

Bile Duct Cancer (Cholangiocarcinoma) Treatment (PDQ®)—Patient Version

Cancer.gov

Treatment of bile duct cancer depends on where the cancer has formed and if it can be removed by surgery (resectable) or not (unresectable). Most bile duct cancers cannot be completely removed by surgery. Other treatments include radiation, chemotherapy, and palliative therapies like stent placement and biliary bypass.

Application of "papillary-like main pancreatic duct invaginated" pancreaticojejunostomy for normal soft pancreas cases.

PubMed

Zhang, Bo; Xu, Jin; Liu, Chen; Long, Jiang; Liu, Liang; Xu, Yongfeng; Wu, Chuntao; Luo, Guopei; Ni, Quanxing; Li, Min; Yu, Xianjun

2013-01-01

Pancreaticojejunostomy is the key procedure of pancreaticoduodenectomy. Our study introduced a new pancreaticojejunal (PJ) anastomosis named "papillary-like main pancreatic duct invaginated" pancreaticojejunostomy. Nighty-two patients underwent pancreaticojejunostomy with either conventional duct-to-mucosa pancreaticojejunostomy or the new "papillary-like main pancreatic duct invaginated" techniques were analyzed retrospectively from January 2010 to September 2012. The incidence of pancreatic fistula was 15.7% (8/51) for the "papillary-like main pancreatic duct invaginated" group and 19.5% (8/41) for the duct-to-mucosa fashion respectively. It is noteworthy that the rate of grade B/C postoperative pancreatic fistula (POPF) in the "papillary-like main pancreatic duct invaginated" group was significantly lower than that of the duct-to-mucosa group (P = 0.039). There were no differences in the incidence of postoperative morbidity and mortality such as postoperative hemorrhage, delayed gastric emptying or remnant pancreatitis. The "papillary-like main pancreatic duct invaginated" pancreaticojejunostomy could provide a feasible option to pancreatic surgeons for patients with normal soft pancreas.

Ducting Conditions for Electromagnetic Wave Propagation in Tropical Disturbances from GPS Dropsonde Data

DTIC Science & Technology

2013-12-01

depression, tropical storm , hurricane, extratropical cyclone, subtropical depression, subtropical storm , a low of no category, tropical wave, disturbance or...surface-based ducts, and elevated ducts. We further separate the duct occurrence based on the location relative to their respective storms . Based...on the number of soundings in different types of tropical disturbances, we chose to further analyze duct conditions in hurricanes and tropical storms

Prospective study of outcomes after percutaneous biliary drainage for malignant biliary obstruction

PubMed Central

Robson, P. C.; Heffernan, N.; Gonen, M.; Thornton, R.; Brody, L. A.; Holmes, R.; Brown, K. T.; Covey, A. M.; Fleischer, D.; Getrajdman, G. I.; Jarnagin, W.; Sofocleous, C.; Blumgart, L.; D’Angelica, M.

2015-01-01

Purpose Percutaneous biliary drainage (PBD) is used to relieve malignant bile duct obstruction (MBO) when endoscopic drainage is not feasible. Little is known about the effects of PBD on the quality of life (QoL) in patients with MBO. The aim of this study was to evaluate changes in QoL and pruritus after PBD and to explore the variables that impact these changes. Patients and Methods Eligible patients reported their QoL and pruritus before and after PBD using the Functional Assessment of Cancer Therapy – Hepatobiliary instrument (FACT-HS) and the Visual Analog Scale for Pruritus (VASP). Instruments were completed pre-procedure and at one and four weeks following PBD. Results One hundred and nine (60 male/49 female) patients enrolled, 102 (94%) had unresectable disease. PBD was technically successful (hepatic ducts cannulated at the conclusion of procedure) in all patients. There were two procedure-related deaths. All-cause mortality was 10% (N=11) at 4 weeks and 28% (N=31) at 8 weeks post PBD with a median survival of 4.74 months. The mean FACT-HS scores declined significantly (P<.01) over time (101.3, 94.8, 94.7 at baseline, 1 week, 4 weeks, respectively). The VASP scores showed significant improvement at 1 week with continued improvement at 4 weeks (P<.01). Conclusion PBD improves pruritus but not QoL in patients with MBO and advanced malignancy. There is high early mortality in this population. PMID:20358300

Thermionic nuclear reactor with internal heat distribution and multiple duct cooling

DOEpatents

Fisher, C.R.; Perry, L.W. Jr.

1975-11-01

A Thermionic Nuclear Reactor is described having multiple ribbon-like coolant ducts passing through the core, intertwined among the thermionic fuel elements to provide independent cooling paths. Heat pipes are disposed in the core between and adjacent to the thermionic fuel elements and the ribbon ducting, for the purpose of more uniformly distributing the heat of fission among the thermionic fuel elements and the ducts.

Performance prediction of a ducted rocket combustor

NASA Astrophysics Data System (ADS)

Stowe, Robert

2001-07-01

The ducted rocket is a supersonic flight propulsion system that takes the exhaust from a solid fuel gas generator, mixes it with air, and burns it to produce thrust. To develop such systems, the use of numerical models based on Computational Fluid Dynamics (CFD) is increasingly popular, but their application to reacting flow requires specific attention and validation. Through a careful examination of the governing equations and experimental measurements, a CFD-based method was developed to predict the performance of a ducted rocket combustor. It uses an equilibrium-chemistry Probability Density Function (PDF) combustion model, with a gaseous and a separate stream of 75 nm diameter carbon spheres to represent the fuel. After extensive validation with water tunnel and direct-connect combustion experiments over a wide range of geometries and test conditions, this CFD-based method was able to predict, within a good degree of accuracy, the combustion efficiency of a ducted rocket combustor.

Iatrogenic bile duct injuries in kashmir valley.

PubMed

Chowdri, Nisar A; Dar, Farooq A; Naikoo, Zahoor A; Wani, Nazir A; Parray, Fazl Q; Wani, Khurshid A

2010-08-01

Cholecystectomy is one of the commonest operations performed throughout the world and bile duct injury is the worst complication of this procedure. In a prospective and retrospective study 25 patients were seen in a tertiary care hospital over a period of 10 years. 72% of patients were referred from other hospitals. 48% of patients presented within one month of injury. Pain was the commonest presentation (92%) followed by jaundice (80%). Liver functions were deranged in 70% of patients, USG revealed biliary dilatation in 69.6% of patients. ERCP was done in 16 patients and revealed cut off of the common hepatic duct in 43.8% of patients. Intraoperative findings revealed adhesions in 96% of patients. 48% of patients had bile duct stricture. Roux-en-Y hepaticojejunostomy was the commonest procedure performed. All patients showed improvement in liver function after surgery. Wound infection was the commonest complication seen in 32% patients. 3 patients died in our series.

Biliary stricture due to neuroma after an innocent blunt abdominal trauma.

PubMed

Katsinelos, P; Dimiropoulos, S; Galanis, I; Tsolkas, P; Paroutoglu, G; Arvaniti, M; Katsiba, D; Baltaglannis, S; Pilpilidis, I; Papagiannis, A; Vaslliadis, I

2002-10-01

A traumatic neuroma of the biliary tract is rarely associated with biliary obstruction. However, when it arises in the common bile duct (CBD) and is associated with obstructive jaundice, it is difficult to distinguish it from bile duct cancer. We describe a patient who developed obstructive jaundice and itching, due to CBD stricture, 8 years after innocent blunt abdominal trauma. The stricture was resected and hepatico-jejunal anastomosis was performed. Histological examination revealed a traumatic neuroma and a fibrous scar around the common bile duct. Symptoms disappeared following surgical removal of the lesion. Blunt abdominal injury may cause the late onset of a fibrous scar and traumatic neuroma in the common bile duct. To our knowledge, a traumatic neuroma of the biliary tract after blunt abdominal trauma has not been reported previously. We review the clinical picture of this relatively rare problem, along with its diagnosis, pathogenesis and treatment.

Characterization of the secondary flow in hexagonal ducts

NASA Astrophysics Data System (ADS)

Marin, O.; Vinuesa, R.; Obabko, A. V.; Schlatter, P.

2016-12-01

In this work we report the results of DNSs and LESs of the turbulent flow through hexagonal ducts at friction Reynolds numbers based on centerplane wall shear and duct half-height Reτ,c ≃ 180, 360, and 550. The evolution of the Fanning friction factor f with Re is in very good agreement with experimental measurements. A significant disagreement between the DNS and previous RANS simulations was found in the prediction of the in-plane velocity, and is explained through the inability of the RANS model to properly reproduce the secondary flow present in the hexagon. The kinetic energy of the secondary flow integrated over the cross-sectional area yz decreases with Re in the hexagon, whereas it remains constant with Re in square ducts at comparable Reynolds numbers. Close connection between the values of Reynolds stress u w ¯ on the horizontal wall close to the corner and the interaction of bursting events between the horizontal and inclined walls is found. This interaction leads to the formation of the secondary flow, and is less frequent in the hexagon as Re increases due to the 120∘ aperture of its vertex, whereas in the square duct the 90∘ corner leads to the same level of interaction with increasing Re. Analysis of turbulence statistics at the centerplane and the azimuthal variance of the mean flow and the fluctuations shows a close connection between hexagonal ducts and pipe flows, since the hexagon exhibits near-axisymmetric conditions up to a distance of around 0.15DH measured from its center. Spanwise distributions of wall-shear stress show that in square ducts the 90∘ corner sets the location of a high-speed streak at a distance zv+≃50 from it, whereas in hexagons the 120∘ aperture leads to a shorter distance of zv+≃38 . At these locations the root mean square of the wall-shear stresses exhibits an inflection point, which further shows the connections between the near-wall structures and the large-scale motions in the outer flow.

Paracellular transport in the collecting duct

PubMed Central

Hou, Jianghui

2016-01-01

Purpose of review The paracellular pathway through the tight junction provides an important route for chloride reabsorption in the collecting duct of the kidney. This review describes recent findings of how defects in paracellular chloride permeation pathway may cause kidney diseases and how such a pathway may be regulated to maintain normal chloride homeostasis. Recent findings The tight junction in the collecting duct expresses two important claudin genes – claudin-4 and claudin-8. Transgenic knockout of either claudin gene causes hypotension, hypochloremia, and metabolic alkalosis in experimental animals. The claudin-4 mediated chloride permeability can be regulated by a protease endogenously expressed by the collecting duct cell – Cap1. Cap1 regulates the intercellular interaction of claudin-4 and its membrane stability. KLHL3, previously identified as a causal gene for Gordon’s syndrome, also known as pseudohypoaldosteronism II (PHA-II), directly interacts with claudin-8 and regulates its ubiquitination and degradation. The dominant PHA-II mutation (R528H) in KLHL3 abolishes claudin-8 binding, ubiquitination, and degradation. Summary The paracellular chloride permeation pathway in the kidney is an important but understudied area in nephrology. It plays vital roles in renal salt handling and regulation of extracellular fluid volume and blood pressure. Two claudin proteins – claudin-4 and claudin-8 contribute to the function of this paracellular pathway. Deletion of either claudin protein from the collecting duct causes renal chloride reabsorption defects and low blood pressure. Claudins can be regulated on post-translational levels by several mechanisms involving protease and ubiquitin ligase. Deregulation of claudins may cause human hypertension as exemplified in the Gordon’s syndrome. PMID:27490784

Should You Have the Air Ducts in Your Home Cleaned?

EPA Pesticide Factsheets

2017-02-14

Duct cleaning generally refers to the cleaning of various heating and cooling system components of forced air systems, including the supply and return air ducts and registers, grilles and diffusers, heat exchangers heating and cooling coils.

Radiative interactions in laminar duct flows

NASA Technical Reports Server (NTRS)

Trivedi, P. A.; Tiwari, S. N.

1990-01-01

Analyses and numerical procedures are presented for infrared radiative energy transfer in gases when other modes of energy transfer occur simultaneously. Two types of geometries are considered, a parallel plate duct and a circular duct. Fully developed laminar incompressible flows of absorbing-emitting species in black surfaced ducts are considered under the conditions of uniform wall heat flux. The participating species considered are OH, CO, CO2, and H2O. Nongray as well as gray formulations are developed for both geometries. Appropriate limiting solutions of the governing equations are obtained and conduction-radiation interaction parameters are evaluated. Tien and Lowder's wide band model correlation was used in nongray formulation. Numerical procedures are presented to solve the integro-differential equations for both geometries. The range of physical variables considered are 300 to 2000 K for temperature, 0.1 to 100.0 atm for pressure, and 0.1 to 100 cm spacings between plates/radius of the tube. An extensive parametric study based on nongray formulation is presented. Results obtained for different flow conditions indicate that the radiative interactions can be quite significant in fully developed incompressible flows.

Navier-Stokes analysis and experimental data comparison of compressible flow within ducts

NASA Technical Reports Server (NTRS)

Harloff, G. J.; Reichert, B. A.; Sirbaugh, J. R.; Wellborn, S. R.

1992-01-01

Many aircraft employ ducts with centerline curvature or changing cross-sectional shape to join the engine with inlet and exhaust components. S-ducts convey air to the engine compressor from the intake and often decelerate the flow to achieve an acceptable Mach number at the engine compressor by increasing the cross-sectional area downstream. Circular-to-rectangular transition ducts are used on aircraft with rectangular exhaust nozzles to connect the engine and nozzle. To achieve maximum engine performance, the ducts should minimize flow total pressure loss and total pressure distortion at the duct exit. Changes in the curvature of the duct centerline or the duct cross-sectional shape give rise to streamline curvature which causes cross stream pressure gradients. Secondary flows can be caused by deflection of the transverse vorticity component of the boundary layer. This vortex tilting results in counter-rotating vortices. Additionally, the adverse streamwise pressure gradient caused by increasing cross-sectional area can lead to flow separation. Vortex pairs have been observed in the exit planes of both duct types. These vortices are due to secondary flows induced by pressure gradients resulting from streamline curvature. Regions of low total pressure are produced when the vortices convect boundary layer fluid into the main flow. The purpose of the present study is to predict the measured flow field in a diffusing S-duct and a circular-to-rectangular transition duct with a full Navier-Stokes computer program, PARC3D, and to compare the numerical predictions with new detailed experimental measurements. The work was undertaken to extend previous studies and to provide additional CFD validation data needed to help model flows with strong secondary flow and boundary layer separation. The S-duct computation extends the study of Smith et al, and Harloff et al, which concluded that the computation might be improved by using a finer grid and more advanced turbulence models

Causes and Prevention of Laparoscopic Bile Duct Injuries

PubMed Central

Way, Lawrence W.; Stewart, Lygia; Gantert, Walter; Liu, Kingsway; Lee, Crystine M.; Whang, Karen; Hunter, John G.

2003-01-01

Objective To apply human performance concepts in an attempt to understand the causes of and prevent laparoscopic bile duct injury. Summary Background Data Powerful conceptual advances have been made in understanding the nature and limits of human performance. Applying these findings in high-risk activities, such as commercial aviation, has allowed the work environment to be restructured to substantially reduce human error. Methods The authors analyzed 252 laparoscopic bile duct injuries according to the principles of the cognitive science of visual perception, judgment, and human error. The injury distribution was class I, 7%; class II, 22%; class III, 61%; and class IV, 10%. The data included operative radiographs, clinical records, and 22 videotapes of original operations. Results The primary cause of error in 97% of cases was a visual perceptual illusion. Faults in technical skill were present in only 3% of injuries. Knowledge and judgment errors were contributory but not primary. Sixty-four injuries (25%) were recognized at the index operation; the surgeon identified the problem early enough to limit the injury in only 15 (6%). In class III injuries the common duct, erroneously believed to be the cystic duct, was deliberately cut. This stemmed from an illusion of object form due to a specific uncommon configuration of the structures and the heuristic nature (unconscious assumptions) of human visual perception. The videotapes showed the persuasiveness of the illusion, and many operative reports described the operation as routine. Class II injuries resulted from a dissection too close to the common hepatic duct. Fundamentally an illusion, it was contributed to in some instances by working too deep in the triangle of Calot. Conclusions These data show that errors leading to laparoscopic bile duct injuries stem principally from misperception, not errors of skill, knowledge, or judgment. The misperception was so compelling that in most cases the surgeon did not

Erlotinib in Treating Patients With Unresectable Liver, Bile Duct, or Gallbladder Cancer

ClinicalTrials.gov

2013-06-03

Adult Primary Cholangiocellular Carcinoma; Adult Primary Hepatocellular Carcinoma; Advanced Adult Primary Liver Cancer; Cholangiocarcinoma of the Extrahepatic Bile Duct; Cholangiocarcinoma of the Gallbladder; Localized Unresectable Adult Primary Liver Cancer; Recurrent Adult Primary Liver Cancer; Recurrent Extrahepatic Bile Duct Cancer; Recurrent Gallbladder Cancer; Unresectable Extrahepatic Bile Duct Cancer; Unresectable Gallbladder Cancer

Performance and Flowfield Measurements on a 10-inch Ducted Rotor VTOL UAV

NASA Technical Reports Server (NTRS)

Martin, Preston; Tung, Chee

2004-01-01

A ducted fan VTOL UAV with a 10-inch diameter rotor was tested in the US Army 7-by 10-Foot Wind Tunnel. The test conditions covered a range of angle of attack from 0 to 110 degrees to the freestream. The tunnel velocity was varied from 0 (simulating a hover condition) to 128 ft/sec in propeller mode. A six-component internal balance measured the aerodynamic loads for a range of model configurations. including the isolated rotor, the isolated duct, and the full configuration of the duct and rotor. For some conditions, hotwire velocity surveys were conducted along the inner and outer surface of the duct and across the downstream wake. In addition, fluorescent oil flow visualization allowed the flow separation patterns inside and outside of the duct to be mapped for a few test conditions. Two different duct shapes were tested to determine the performance effects of leading edge radius. For each duct, a range of rotor tip gap from 1%R to 4.5%R was tested to determine the performance penalty in hover and axial flight. Measured results are presented in terms of hover performance, hover performance in a crosswind, and high angle of attack performance in propeller mode. In each case, the effects of both tip gap and duct leading edge radius are illustrated using measurements. Some of the hover performance issues were also studied using a simple analytical method, and the results agreed with the measurements.

Endoscopic management of difficult common bile duct stones

PubMed Central

Trikudanathan, Guru; Navaneethan, Udayakumar; Parsi, Mansour A

2013-01-01

Endoscopy is widely accepted as the first treatment option in the management of bile duct stones. In this review we focus on the alternative endoscopic modalities for the management of difficult common bile duct stones. Most biliary stones can be removed with an extraction balloon, extraction basket or mechanical lithotripsy after endoscopic sphincterotomy. Endoscopic papillary balloon dilation with or without endoscopic sphincterotomy or mechanical lithotripsy has been shown to be effective for management of difficult to remove bile duct stones in selected patients. Ductal clearance can be safely achieved with peroral cholangioscopy guided laser or electrohydraulic lithotripsy in most cases where other endoscopic treatment modalities have failed. Biliary stenting may be an alternative treatment option for frail and elderly patients or those with serious co morbidities. PMID:23345939

Congenital Atresia of Wharton’s Duct

PubMed Central

Hseu, Anne; Anne, Premchand

2016-01-01

This is a case report of a three-month-old male who presented to clinic with a cystic lesion under the tongue. On clinical examination, a cystic lesion was observed in the, floor-of-mouth. The patient was referred to Paediatric Otorhinolaryngology service for further management. The differential diagnoses for floor-of-mouth lesions should be reviewed with primary focus on the Wharton’s duct atresia and its management. It is crucial to recognize submandibular duct atresia in the primary Paediatric clinic in order to expedite management of lesion before complications arise including infection, enlargement of cyst, and feeding and breathing difficulties. PMID:27042492

[The Management of Common Bile Duct Stones].

PubMed

Park, Chang Hwan

2018-05-25

Common bile duct (CBD) stone is a relatively frequent disorder with a prevalence of 10-20% in patients with gallstones. This is also associated with serious complications, including obstructive jaundice, acute suppurative cholangitis, and acute pancreatitis. Early diagnosis and prompt treatment is the most important for managing CBD stones. According to a recent meta-analysis, endoscopic ultrasonography and magnetic resonance cholangiopancreatography have high sensitivity, specificity, and accuracy for the diagnosis of CBD stones. Endoscopic ultrasonography, in particular, has been reported to have higher sensitivity between them. A suggested management algorithm for patients with symptomatic gallstones is based on whether they are at low, intermediate, or high probability of CBD stones. Single-stage laparoscopic CBD exploration and cholecystectomy is superior to endoscopic retrograde cholangiopancreatography (ERCP) plus laparoscopic cholecystectomy with respect to technical success and shorter hospital stay in high risk patients with gallstones and CBD stones, where expertise, operative time, and instruments are available. ERCP plus laparoscopic cholecystectomy is usually performed to treat patients with CBD stones and gallstones in many institutions. Patients at intermediate probability of CBD stones after initial evaluation benefit from additional biliary imaging. Patients with a low probability of CBD stones should undergo cholecystectomy without further evaluation. Endoscopic sphincterotomy and endoscopic papillary balloon dilation in ERCP are the primary methods for dilating the papilla of Vater for endoscopic removal of CBD stones. Endoscopic papillary large balloon dilation is now increasingly performed due to the usefulness in the management of giant or difficult CBD stones. Scheduled repeated ERCP may be considered in patients with high risk of recurrent CBD stones.

A Case of Recurrent Schneiderian Papilloma of the Lacrimal Sac Invading the Nasal Cavity

PubMed Central

Jang, Ji Hye; Choe, Mi Sun

2009-01-01

A 44-year-old man presented with a history of chronic epiphora, discharge from the right eye, and a palpable mass in the medial canthal area. Irrigation of the lacrimal system revealed bloody discharge. Orbital magnetic resonance imaging (MRI) showed a well-defined heterogeneous enhanced mass filling the lacrimal sac and upper nasolacrimal duct (NLD). A wide excision and surgical biopsy were performed. Histopathology showed the tumor to be an exophytic Schneiderian papilloma with moderate to severe dysplasia. Three months later, the mass was found to be invading the nasal cavity through the NLD. Endoscopic histopathological evaluation confirmed that it was identical to the originally identified papilloma. PMID:19568358

Contrast-enhanced ultrasonography for the evaluation of liver fibrosis after biliary obstruction.

PubMed

Shin, Hyun Joo; Chang, Eun Young; Lee, Hye Sun; Hong, Jung Hwa; Park, Gyuri; Kim, Hyun Gi; Kim, Myung-Joon; Lee, Mi-Jung

2015-03-07

To investigate perfusion change in contrast-enhanced ultrasonography (CEUS) to evaluate liver fibrosis based on biliary obstruction using an animal model. New Zealand white rabbits (3-4 kg) underwent bile duct ligation to form a biliary obstruction model. We performed liver CEUS and laboratory tests on the day before the operation (day 0) and every 7 postoperative days until the rabbits were sacrificed. After CEUS, signal intensity of liver parenchyma with a time-intensity curve was analyzed. Perfusion parameters were automatically calculated from region-of-interests, including peak signal intensity, mean transit time, area under the curve and time to peak. Histological grades of liver fibrosis were assessed according to the Metavir score system immediately after sacrifice. Generalized estimating equations were used to analyze the association between liver fibrosis grades and perfusion parameters for statistical analysis. The perfusion parameters were measured on the last day and the difference between day 0 and the last day were evaluated. From the nine rabbits, histological grades of liver fibrosis were grade 1 in one rabbit, grade 2 and 3 in three rabbits each, and grade 4 in two rabbits. Among the four CEUS parameters, only the peak signal intensity measured on the last day demonstrated a significant association with liver fibrosis grades (OR = 1.392, 95%CI: 1.114-1.741, P = 0.004). The difference in peak signal intensity between day 0 and the last day also demonstrated an association with liver fibrosis (OR = 1.191, 95%CI: 0.999-1.419, P = 0.051). The other parameters tested, including mean transit time, area under the curve, and time to peak, showed no significant correlation with liver fibrosis grades. This animal study demonstrates that CEUS can be used to evaluate liver fibrosis from biliary obstruction using peak signal intensity as a parameter.

Effects of Lactobacillus plantarum on gut barrier function in experimental obstructive jaundice

PubMed Central

Zhou, Yu-Kun; Qin, Huan-Long; Zhang, Ming; Shen, Tong-Yi; Chen, Hong-Qi; Ma, Yan-Lei; Chu, Zhao-Xin; Zhang, Peng; Liu, Zhi-Hua

2012-01-01

AIM: To investigate the mechanisms of Lactobacillus plantarum (L. plantarum) action on gut barrier in preoperative and postoperative experimental obstructive jaundice in rats. METHODS: Forty rats were randomly divided into groups of sham-operation, bile duct ligation (BDL), BDL + L. plantarum, BDL + internal biliary drainage (IBD), and BDL + IBD + L. plantarum. Ten days after L. plantarum administration, blood and ileal samples were collected from the rats for morphological examination, and intestinal barrier function, liver function, intestinal oxidative stress and protein kinase C (PKC) activity measurement. The distribution and expression of the PKC and tight junction (TJ) proteins, such as occludin, zonula occludens-1, claudin-1, claudin-4, junction adhesion molecule-A and F-actin, were examined by confocal laser scanning microscopy, immunohistochemistry, Western blotting, real-time fluorescent quantitative polymerase chain reaction assay. RESULTS: L. plantarum administration substantially restored gut barrier, decreased enterocyte apoptosis, improved intestinal oxidative stress, promoted the activity and expression of protein kinase (BDL vs BDL + L. plantarum, 0.295 ± 0.007 vs 0.349 ± 0.003, P < 0.05; BDL + IBD vs BDL + IBD + L. plantarum, 0.407 ± 0.046 vs 0.465 ± 0.135, P < 0.05), and particularly enhanced the expression and phosphorylation of TJ proteins in the experimental obstructive jaundice (BDL vs BDL + L. plantarum, 0.266 ± 0.118 vs 0.326 ± 0.009, P < 0.05). The protective effect of L. plantarum was more prominent after internal biliary drainage ( BDL + IBD vs BDL + IBD + L. plantarum, 0.415 ± 0.105 vs 0.494 ± 0.145, P < 0.05). CONCLUSION: L. plantarum can decrease intestinal epithelial cell apoptosis, reduce oxidative stress, and prevent TJ disruption in biliary obstruction by activating the PKC pathway. PMID:22912548

Effects of Lactobacillus plantarum on gut barrier function in experimental obstructive jaundice.

PubMed

Zhou, Yu-Kun; Qin, Huan-Long; Zhang, Ming; Shen, Tong-Yi; Chen, Hong-Qi; Ma, Yan-Lei; Chu, Zhao-Xin; Zhang, Peng; Liu, Zhi-Hua

2012-08-14

To investigate the mechanisms of Lactobacillus plantarum (L. plantarum) action on gut barrier in preoperative and postoperative experimental obstructive jaundice in rats. Forty rats were randomly divided into groups of sham-operation, bile duct ligation (BDL), BDL + L. plantarum, BDL + internal biliary drainage (IBD), and BDL + IBD + L. plantarum. Ten days after L. plantarum administration, blood and ileal samples were collected from the rats for morphological examination, and intestinal barrier function, liver function, intestinal oxidative stress and protein kinase C (PKC) activity measurement. The distribution and expression of the PKC and tight junction (TJ) proteins, such as occludin, zonula occludens-1, claudin-1, claudin-4, junction adhesion molecule-A and F-actin, were examined by confocal laser scanning microscopy, immunohistochemistry, Western blotting, real-time fluorescent quantitative polymerase chain reaction assay. L. plantarum administration substantially restored gut barrier, decreased enterocyte apoptosis, improved intestinal oxidative stress, promoted the activity and expression of protein kinase (BDL vs BDL + L. plantarum, 0.295 ± 0.007 vs 0.349 ± 0.003, P < 0.05; BDL + IBD vs BDL + IBD + L. plantarum, 0.407 ± 0.046 vs 0.465 ± 0.135, P < 0.05), and particularly enhanced the expression and phosphorylation of TJ proteins in the experimental obstructive jaundice (BDL vs BDL + L. plantarum, 0.266 ± 0.118 vs 0.326 ± 0.009, P < 0.05). The protective effect of L. plantarum was more prominent after internal biliary drainage ( BDL + IBD vs BDL + IBD + L. plantarum, 0.415 ± 0.105 vs 0.494 ± 0.145, P < 0.05). L. plantarum can decrease intestinal epithelial cell apoptosis, reduce oxidative stress, and prevent TJ disruption in biliary obstruction by activating the PKC pathway.

Novel immunohistochemical markers differentiate intrahepatic cholangiocarcinoma from benign bile duct lesions.

PubMed

Bertram, Stefanie; Padden, Juliet; Kälsch, Julia; Ahrens, Maike; Pott, Leona; Canbay, Ali; Weber, Frank; Fingas, Christian; Hoffmann, Andreas C; Vietor, Antonie; Schlaak, Joerg F; Eisenacher, Martin; Reis, Henning; Sitek, Barbara; Baba, Hideo A

2016-07-01

The distinction between intrahepatic cholangiocarcinoma (ICC) and benign bile duct lesions can be challenging. Using our previously identified potential biomarkers for ICC, we examined whether these are useful for the differential diagnosis of ICC, bile duct adenoma and reactive bile duct proliferations in an immunohistochemical approach and identified a diagnostic marker panel including known biomarkers. Subjects included samples from 77 patients with ICC, 33 patients with bile duct adenoma and 47 patients with ductular reactions in liver cirrhosis. Our previously identified biomarkers (stress-induced phosphoprotein 1 (STIP1), SerpinH1, 14-3-3Sigma) were tested immunohistochemically following comparison with candidates from the literature (cluster of differentiation 56, heat shock protein (HSP)27, HSP70, B-cell-lymphoma2, p53, ki67). The expression of SerpinH1 and 14-3-3Sigma was significantly higher in ICC than in bile duct adenomas and ductular reactions (p<0.05), whereas STIP1 expression was significantly higher (p<0.05) in ICC than in ductular reactions, but the difference to the bile duct adenoma group was not significant. A panel of the biomarker SerpinH1, 14-3-3Sigma and ki67 (≥2 marker positive) showed a high diagnostic accuracy (sensitivity 87.8%, specificity 95.9%, accuracy 91.8%) in the differential diagnosis of ICC versus non-malignant bile duct lesions. This suggests that 14-3-3Sigma and SerpinH1 may be useful in the differential diagnosis of malignant, benign and reactive bile duct lesions in addition to ki67 where a cut-off of >5% might be used for the distinction of malignant and non-malignant lesions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Liver segment IV hypoplasia as a risk factor for bile duct injury.

PubMed

Mercado, Miguel Angel; Franssen, Bernardo; Arriola, Juan Carlos; Garcia-Badiola, Artemio; Arámburo, Rigoberto; Elnecavé, Alejandro; Cortés-González, Rubén

2011-09-01

Bile duct injury remains constant in the era of laparoscopic cholecystectomy and misidentification of structures remains one of the most common causes of such injuries. Abnormalities in liver segment IV, which is fully visible during laparoscopic cholecystectomy, may contribute to misidentification as proposed herein. We describe the case of a 36-year-old female who had a bile duct injury during a laparoscopic cholecystectomy where the surgeon noticed an unusually small distance between the gallbladder and the round ligament. We define hypoplasia of liver segment IV as well as describe the variation of the biliary anatomy in the case. We also intend to fit it in a broader spectrum of developmental anomalies that have both hyopoplasia of some portion of the liver and variations in gallbladder and bile duct anatomy that may contribute to bile duct injury. To our knowledge, hypoplasia of liver segment IV has not been suggested in the literature as a risk factor for bile duct injury except in the extreme case of a left-sided gallbladder. Surgeons should be vigilant during laparoscopic cholecystectomy when they become aware of an unusually small distance between the gallbladder bed and the round ligament prior to beginning their dissection, variations in the common bile duct and cystic duct should be expected.

[From Langenbuch to Strasberg: the spectrum of bile duct injuries].

PubMed

Mercado, Miguel Angel

2004-01-01

Bile duct injuries are the main serious complication of laparoscopy cholecystectomy. The frequency of this type of injuries rangers, between 1 to 3 in 1,000 cases and although this rate remains stables, their frequency has increased because of the increasing expansion of the indication of cholecystectomy. Each lesion is the individual in it's features as well as the scenario in which the surgeon faces it. Several classifications have been developed, but that developed by Strasberg most used nowadays. Intraoperative cholangiography has shown evidence in meta analytic studies that diminishes the frequency of lesions but does not abolish them. Conversion from laparoscope's to the open approach with ample and convincent dissection is probably the best maneuver to reduce the frequency of lesions, when any anatomical or technical doubt appears. No patient should be operated in critical condition. In this situation, biliary reconstruction has a secondary role and only drainage of the ducts (percutaneous or surgical) is indicated. Roux en Y hepatoyeyunostomy is the procedure of choice for almost all cases, leaving other types of procedures for selected cases. Transhepatic transanastomotical stents should be used according to the individual status of the patient when small, scared or inflamed ducts are found. High quality anastomosis is obtained when proper ducts are found. Sometimes high dissection of the ducts is needed in order to obtain adequate ducts. Nine of each ten cases are completely rehabilitated, obtaining a good quality of life.

Time course of collagen peak in bile duct-ligated rats.

PubMed

Tarcin, Orhan; Basaranoglu, Metin; Tahan, Veysel; Tahan, Gülgün; Sücüllü, Ilker; Yilmaz, Nevin; Sood, Gagan; Snyder, Ned; Hilman, Gilbert; Celikel, Cigdem; Tözün, Nurdan

2011-04-28

One of the most useful experimental fibrogenesis models is the "bile duct-ligated rats". Our aim was to investigate the quantitative hepatic collagen content by two different methods during the different stages of hepatic fibrosis in bile duct-ligated rats on a weekly basis. We questioned whether the 1-wk or 4-wk bile duct-ligated model is suitable in animal fibrogenesis trials. Of the 53 male Wistar rats, 8 (Group 0) were used as a healthy control group. Bile duct ligation (BDL) had been performed in the rest. Bile duct-ligated rates were sacrificed 7 days later in group 1 (10 rats), 14 days later in group 2 (9 rats), 21 days later in group 3(9 rats) and 28 days later in group 4 (9 rats). Eight rats underwent sham-operation (Sham). Hepatic collagen measurements as well as serum levels of liver enzymes and function tests were all analysed. The peak level of collagen was observed biochemically and histomorphometricly at the end of third week (P < 0.001 and P < 0.05). Suprisingly, collagen levels had decreased with the course of time such as at the end of fourth week (P < 0.01 and P < 0.05). We have shown that fibrosis in bile duct-ligated rats is transient, i.e. reverses spontaneously after 3 weeks. This contrasts any situation in patients where hepatic fibrosis is progressive and irreversible as countless studies performed by many investigators in the same animal model.

Ducted whistler-mode signals received at two widely spaced locations

NASA Astrophysics Data System (ADS)

Clilverd, M. A.; Thomson, N. R.; Smith, A. J.

1996-06-01

Whistler-mode signals from a single VLF transmitter that have propagated in the same duct, have been observed simultaneously at Faraday, Antarctica (65°S, 64°W) and Dunedin, New Zealand (46°S, 171°E). The signals received have group-delay times that differ in the order of 10 ms, which can be explained by the differences in southern-hemisphere sub-ionospheric propagation time from duct exit region to receiver for the two sites. This difference has been used to determine the location of the duct exit region, with confirmation provided by arrival-bearing information from both sites. The whistler-mode signals typically occur one or two days after geomagnetic activity, with Kpgeq5. The sub-ionospheric-propagation model, LWPC, is used to estimate the whistler-mode power radiated from the duct exit region. These results are then combined with estimated loss values for ionospheric and ducted transmission to investigate the role of wave-particle amplification or absorption. On at least half of the events studied, plasmaspheric amplification of the signals appears to be needed to explain the observed whistler-mode signal strengths.

46 CFR 32.56-60 - Ventilation ducts-T/ALL.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 1 2011-10-01 2011-10-01 false Ventilation ducts-T/ALL. 32.56-60 Section 32.56-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS SPECIAL EQUIPMENT, MACHINERY, AND HULL....56-60 Ventilation ducts—T/ALL. (a) Each duct for ventilation of Category A machinery spaces that...

46 CFR 32.56-60 - Ventilation ducts-T/ALL.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Ventilation ducts-T/ALL. 32.56-60 Section 32.56-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS SPECIAL EQUIPMENT, MACHINERY, AND HULL....56-60 Ventilation ducts—T/ALL. (a) Each duct for ventilation of Category A machinery spaces that...

Measurements of compressible secondary flow in a circular S-duct

NASA Technical Reports Server (NTRS)

Vakili, A.; Wu, J. M.; Liver, P.; Bhat, M. K.

1983-01-01

This paper presents the results of an experimental study of secondary flow in a circular cross section 30 deg - 30 deg S-duct with entrance Mach number of 0.6. Local flow velocity vectors have been measured along the length of the duct at six stations. These measurements have been made using a five-port cone probe. Static and total pressure profiles in the transverse planes are obtained from the cone probe measurements. Wall static pressure measurements along three azimuth angles of 0 deg, 90 deg, and 180 deg along the duct are also made. Contour plots presenting the three dimensional velocity field as well as the total- and static-pressure fields are obtained. Surface oil flow visualization technique has been used to provide details of the flow on the S-duct boundaries. The experimental observations have been compared with typical computational results.

Importance of resin ducts in reducing ponderosa pine mortality from bark beetle attack.

PubMed

Kane, Jeffrey M; Kolb, Thomas E

2010-11-01

The relative importance of growth and defense to tree mortality during drought and bark beetle attacks is poorly understood. We addressed this issue by comparing growth and defense characteristics between 25 pairs of ponderosa pine (Pinus ponderosa) trees that survived and trees that died from drought-associated bark beetle attacks in forests of northern Arizona, USA. The three major findings of our research were: (1) xylem resin ducts in live trees were >10% larger (diameter), >25% denser (no. of resin ducts mm(-2)), and composed >50% more area per unit ring growth than dead trees; (2) measures of defense, such as resin duct production (no. of resin ducts year(-1)) and the proportion of xylem ring area to resin ducts, not growth, were the best model parameters of ponderosa pine mortality; and (3) most correlations between annual variation in growth and resin duct characteristics were positive suggesting that conditions conducive to growth also increase resin duct production. Our results suggest that trees that survive drought and subsequent bark beetle attacks invest more carbon in resin defense than trees that die, and that carbon allocation to resin ducts is a more important determinant of tree mortality than allocation to radial growth.

Computer analysis of three-dimensional morphological characteristics of the bile duct

NASA Astrophysics Data System (ADS)

Ma, Jinyuan; Chen, Houjin; Peng, Yahui; Shang, Hua

2017-01-01

In this paper, a computer image-processing algorithm for analyzing the morphological characteristics of bile ducts in Magnetic Resonance Cholangiopancreatography (MRCP) images was proposed. The algorithm consisted of mathematical morphology methods including erosion, closing and skeletonization, and a spline curve fitting method to obtain the length and curvature of the center line of the bile duct. Of 10 cases, the average length of the bile duct was 14.56 cm. The maximum curvature was in the range of 0.111 2.339. These experimental results show that using the computer image-processing algorithm to assess the morphological characteristics of the bile duct is feasible and further research is needed to evaluate its potential clinical values.

Acquired external punctal stenosis: surgical management and long-term follow-up.

PubMed

Kashkouli, Mohsen Bahmani; Beigi, Bijan; Astbury, Nick

2005-06-01

To introduce and assess the results of a long-term follow-up of a one-snip punctoplasty with monocanalicular stent (Mini Monoka) for acquired external punctal stenosis (AEPS) with and without associated internal punctal and canalicular stenosis. Prospective non-comparative interventional case series. Thirty-five eligible patients (53 eyes) with AEPS underwent a horizontal one-snip punctoplasty and Mini Monoka tube insertion by or under supervision of a consultant Oculoplastic surgeon from June 1999 to May 2002. Diagnostic probing and irrigation were performed before operation and after operation at the last follow-up. Patients with canalicular obstruction, nasolacrimal duct stenosis and obstruction, and those with less than 6 months' follow-up were excluded. The Chi-square (X(2)), Fisher's exact, Pearson correlation, and multiple logistic regression analysis tests, with 95% confidence interval when appropriate, were used for statistical analysis. The age range was 39 to 90 years (mean: 67.2, SD: 11.8, SE: 2). Twenty-seven patients (77.1%) were female. There was a normal canalicular system in 21 (39.6%), lower canalicular stenosis in 10 (18.8%), and internal punctal stenosis in 22 (41.5%) eyes. Postoperative follow-up was from 6 to 41 months (mean: 18.5, SD: 9.2, SE: 1.2). There was a 77.4% complete functional success, 7.5% partial functional success, and 96.2% anatomical success at the last follow-up. The success rate was not significantly different between the eyes with and without preoperative internal punctal and canalicular stenosis (p = 0.4). The lower success rate was significantly correlated with a final abnormal probing and irrigation (p < 0.01). The use of a monocanalicular Mini Monoka stent together with a one-snip punctoplasty is helpful to prevent the recurrence of punctal stenosis in the healing phase and addresses the associated internal punctal and canalicular stenosis.

Results of the application of intraoperative mitomycin C in dacryocystorhinostomy.

PubMed

Roozitalab, M H; Amirahmadi, M; Namazi, M R

2004-01-01

Dacryocystorhinostomy (DCR) is widely accepted as the procedure of choice for surgical correction of lacrimal drainage system obstruction distal to common canaliculus in adulthood. The success rate of DCR has been reported to be from 63% to 99%. DCR failure has been attributed to membranous occlusion of the rhinostomy site caused by soft tissue scarring. More recently, use of mitomycin C (MMC) has been described in lacrimal drainage surgery. The beneficial effect of MMC as a surgical adjunct is thought to be related to its potent inhibition of fibroblast proliferation. To improve the success rate of DCR, the authors used MMC as an adjunct to surgery in 130 patients with nasolacrimal duct obstruction undergoing lacrimal surgery. They were assigned randomly into a MMC DCR group and a regular DCR group (control group). The mean age of the MMC group was 40+/-15 years and that of the control group was 42+/-16 years. The standard surgical techniques of an external DCR were used in all patients of both groups. Patients were followed for 6 months. The authors evaluated the patients with subjective symptoms (improvement in tearing) and objective findings such as the height of tear meniscus, fluorescein dye test, and patency at the time of irrigation. There was no significant difference in the age between the two groups (p=1.00). Six patients in the mitomycin group were symptomatic after 6 months' follow-up; probe and irrigation showed non-patency of lacrimal system. The success rate in the MMC group was therefore 90.5% (59/65), and in the conventional group it was 92.4% (60/65). No significant difference between the two groups was present (p=0.75). The authors conclude that the use of intraoperative MMC in DCR surgery does not change the success rate of this procedure.

Endoscopic guided single self-linking silicone stent in pediatric external dacryocystorhinostomy.

PubMed

Ali, Mohammad Javed; Gupta, Himika; Naik, Milind N; Honavar, Santosh G

2013-09-01

To study the efficacy of a new technique of single self-linking silicone stent exclusively in pediatric external dacryocystorhinostomy (DCR) and to report the new use and advantages of endoscopic guidance for the same. Prospective interventional case series, including 11 eyes of ten patients with nasolacrimal duct obstruction. Data collected included demographic data, clinical presentation, laterality, status of lids and puncta, syringing findings, probing interpretations, types and duration of intubation. Consecutive pediatric patients with post-saccal obstruction who underwent an external dacryocystorhinostomy were included. Exclusion criteria included patients who had undergone a DCR in the past by any route via external, endonasal or transcanalicular. Primary outcome measures were stent retention and ease of stent removal. Secondary outcome measures were anatomic patency of the passage and resolution of symptoms. There were three male and seven female patients. Mean age was 9.4 years (range 6-15). A total of 11 procedures were carried out. Following placement of self-linked stents, the removal was done at a mean duration of 13.2 weeks (range:12-16 weeks). None of the patients had a stent prolapse during this period. All stents were removed in the outpatient without the use of general anesthesia with minimal endoscopic guidance. A minimum follow-up of three months following removal was considered for final analysis. Follow-up ranged from three months to six months after tube removal. The anatomical and functional success rate was 91%. There was one anatomical failure three months following tube removal and the remaining patients were free of symptoms at the last follow-up. Self-linking stents are a useful modality in pediatric patients not only to prevent stent prolapse but also to allow easy removal with minimum discomfort. Endoscopic guidance is a useful addition to this technique.

CT differentiation of mucin-producing cystic neoplasms of the liver from solitary bile duct cysts.

PubMed

Kim, Hyoung Jung; Yu, Eun Sil; Byun, Jae Ho; Hong, Seung-Mo; Kim, Kyoung Won; Lee, Jong Seok; Kim, So Yeon

2014-01-01

The purpose of this study was to identify the CT features required for differentiating mucin-producing cystic neoplasms of the liver (mucinous cystic neoplasms and cyst-forming intraductal papillary neoplasms of the bile duct) from solitary bile duct cysts. CT images of pathologically confirmed mucinous cystic neoplasms (n = 15), cyst-forming intraductal papillary neoplasms of the bile duct (n = 16), and solitary bile duct cysts (n = 31) were reviewed. Analysis of the CT findings included shape, presence of septa, location of septa (peripheral vs central), thickness of septa (thin vs thick), mosaic pattern, mural nodules, intracystic debris, calcification, upstream bile duct dilatation, downstream bile duct dilatation, and communication between a cystic lesion and the bile duct. The maximum size of a cystic lesion and the maximum size of the largest mural nodule were measured. The presence of septa, central septa, mural nodules, upstream bile duct dilatation, and downstream bile duct dilatation were found to be significant CT findings for differentiating mucinous cystic neoplasms and cyst-forming intraductal papillary neoplasms of the bile duct from solitary bile duct cysts (p < 0.05 for each finding). When two of these five criteria were used in combination, the sensitivity and specificity for diagnosing mucin-producing cystic neoplasms and cyst-forming intraductal papillary neoplasms of the bile duct were 87% (27 of 31) and 87% (27 of 31), respectively. When two of these five criteria were used in combination, the sensitivity and specificity for diagnosing mucinous cystic neoplasms and cyst-forming intraductal papillary neoplasms of the bile duct were 87% (27 of 31) and 87% (27 of 31), respectively [corrected]. With the use of specific CT criteria, mucin-producing cystic neoplasms of the liver can be differentiated from solitary bile duct cysts with a high degree of accuracy.