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Sample records for expandable nitinol stent

  1. Malignant duodenal obstructions: palliative treatment with covered expandable nitinol stent

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Chul; Jung, Gyoo Sik; Lee, Sang Hee; Kim, Sung Min; Oh, Kyung Seung; Huh, Jin Do; Cho, Young Duk [College of Medicine, Kosin Univ, Pusan (Korea, Republic of); Song, Ho Young [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of)

    2002-04-01

    To evaluate the feasibility and clinical effectiveness of using a polyurethane-covered expandable nitinol stent in the palliative treatment of malignant duodenal obstruction. Under fluoroscopic guidance, a polyurethane-covered expandable nitinol stent was placed in 12 consecutive patients with malignant duodenal obstructions. All presented with severe nausea and recurrent vomiting. The underlying causes of obstruction were duodenal carcinoma (n=4), pancreatic carcinoma (n=4), gall bladder carcinoma (n=2), distal CBD carcinoma (n=1), and uterine cervical carcinoma (n=1). The sites of obstruction were part I (n=1), part II (n=8), and III (n=3). Due to pre-existing jaundice, eight patients with part II obstructions underwent biliary decompression prior to stent placement. An introducer sheath with a 6-mm outer diameter and stents 16 mm in diameter were employed, and to place the stent, and after-loading technique was used. Stent placement was technically successful in ten patients, and no procedural complications occuured. In one of two patients in whom there was technical failure, and in whom the obstructions were located in part III, the stent was placed transgastrically. Stent migration occurred in one patient four days after the procedure, and treatment involved the palcement of a second, uncovered, nitinol stent. After stent placement, symptoms improved in all patients. During follow-up, obstructive symptoms due to stent stenosis (n=1), colonic obstruction (n=1), and multiple small bowel obstruction (n=1) recurred in three patients. Two of these were treated by placing additional stents in the duodenum and colon, respectively. One of the eight patients in whom a stent was placed in the second portion of the duodenum developed jaundice. The patients died a mean 14 (median, 9) weeks after stent placement. The placement of a polyurethane-covered expandable nitinol stent seems to be technically feasible, safe and effective for the palliative treatment of malignant

  2. Results of the new nitinol self-expandable stents for distal biliary structures

    NARCIS (Netherlands)

    Smits, M.; Huibregtse, K.; Tytgat, G.

    1995-01-01

    The nitinol stent is a self-expandable spiral stent made of nickel-titanium alloy. We performed a pilot study to evaluate the method of stent insertion and stent efficacy. Twenty-eight patients with irresectable malignancy had nitinol stents inserted for obstructive jaundice due to distal biliary

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

    Science.gov (United States)

    Ghazi, Payam; Haji-Zeinali, Ali-Mohammad

    2010-01-01

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

  4. Self-expandable nitinol stent placement in homocysteinemic porcine aorta

    Directory of Open Access Journals (Sweden)

    Luís Henrique Gil França

    2008-01-01

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

  5. [Self-expanding nitinol stents in proximal tracheal stenosis].

    Science.gov (United States)

    Hafner, B; Mann, W; Heussel, C P; Scherhag, A; Schlegel, J; Kauczor, H U

    2000-03-01

    The use of silicone- or metal stents in stenosis of the distal trachea and the bronchial system is a customary procedure [1-4], for example after tumor invasion or cicatricial stenosis after transplantation. In the proximal part of the trachea, on smaller, short and soft strictures we try to stabilise the trachea by the implantation of rings. Other methods are tracheal plasty or transverse tracheal resectomy [5-7]. In the case of longer or nearer subglottal stenoses the positioning of self-expanding nitinol stents has proven a simple, gentle and well-tolerated alternative procedure even in very serious disorders [1, 8, 9]. These stents can be placed in short narcosis under endoscopic control without great strain on the patient. We placed nitinol-stents in the proximal part of the trachea in eleven cases. In five cases dyspnoea caused by a tracheal collapse improved. In two further cases a tracheal stenosis with massive granulation tissue and cicatricial pull under an inlaid tracheal cannula was removed and the tracheostoma was closed. In four cases a solid, scarred and cartilaginous stenosis in the area of the cricoid and the upper tracheal rings was widened with laser and later on stented. Over an observation time of two years no complications showed safe one case in which a directly postoperative dislocation was repositioned quickly. The patients live without restrictions through the tracheal stenosis or a tracheostoma. In the best possible case epithelialization over the metal meshes develops so that a nearly normal mucus transportation is possible [1, 10-12].

  6. Treatment of malignant gastroduodenal obstruction with using a newly designed complex expandable nitinol stent: initial experiences

    International Nuclear Information System (INIS)

    Jung, Mi Hee; Ko, Ji Ho; Lee, Eun Jung; Oh, Kyeng Seung; Huh, Jin Do; Cho, Young Duk; Park, Seun Ja; Jung, Gyoo Sik

    2005-01-01

    We wanted to evaluate the usefulness of a new type of a complex expandable nitinol stent that was designed to reduce the stent's propensity to migration during the treatment of malignant gastroduodenal obstructions. Two types of expandable nitinol stent were constructed by weaving a single thread of 0.2mm nitinol wire in a tubular configuration: an uncovered stent 18mm in diameter and a covered stent 16mm in diameter. Both ends of the covered stent were fabricated by coaxially inserting the covered stent into the tubular uncovered stent and then attaching the two stents together with using nylon monofilament. Under fluoroscopic guidance, the stent was placed in 29 consecutive patients (20 men and 9 women, mean age: 65 years) who were suffering with malignant gastric outlet obstruction (n=20), duodenal obstruction (n=6) or combined obstruction (n=3). Clinical improvement was assessed by comparing the food intake capacity before and after the procedure. The complications were investigated during the follow up period. Stent placement was successful in all the patients. After stent placement, the symptoms improved in all but one patient. During the follow up, stent migration occurred in one patient (3%) at 34 days after the procedure. Despite the stent migration, the patient was able to resume a soft diet. Six patients developed recurrent symptoms of obstruction with tumor overgrowth at a mean of 145 days after the procedure; all the patients underwent coaxial placement of an additional stent with good results. One patient showed recurrence of obstruction due to tumor in-growth, and this was treated by placement of a second stent. Two patients with stent placement in the duodenum suffered from jaundice 26 days and 65 days, respectively, after their procedures. Placement of the newly designed complex expandable nitinol stent seems to be effective for the palliative treatment of malignant gastroduodenal obstructions. The new stent also seems to help overcome the

  7. Treatment of malignant gastroduodenal obstruction with using a newly designed complex expandable nitinol stent: initial experiences

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Mi Hee; Ko, Ji Ho; Lee, Eun Jung; Oh, Kyeng Seung; Huh, Jin Do; Cho, Young Duk; Park, Seun Ja [College of Medicine, Kosin University, Busan (Korea, Republic of); Jung, Gyoo Sik [Ulsan Hospital, Ulsan (Korea, Republic of)

    2005-12-15

    We wanted to evaluate the usefulness of a new type of a complex expandable nitinol stent that was designed to reduce the stent's propensity to migration during the treatment of malignant gastroduodenal obstructions. Two types of expandable nitinol stent were constructed by weaving a single thread of 0.2mm nitinol wire in a tubular configuration: an uncovered stent 18mm in diameter and a covered stent 16mm in diameter. Both ends of the covered stent were fabricated by coaxially inserting the covered stent into the tubular uncovered stent and then attaching the two stents together with using nylon monofilament. Under fluoroscopic guidance, the stent was placed in 29 consecutive patients (20 men and 9 women, mean age: 65 years) who were suffering with malignant gastric outlet obstruction (n=20), duodenal obstruction (n=6) or combined obstruction (n=3). Clinical improvement was assessed by comparing the food intake capacity before and after the procedure. The complications were investigated during the follow up period. Stent placement was successful in all the patients. After stent placement, the symptoms improved in all but one patient. During the follow up, stent migration occurred in one patient (3%) at 34 days after the procedure. Despite the stent migration, the patient was able to resume a soft diet. Six patients developed recurrent symptoms of obstruction with tumor overgrowth at a mean of 145 days after the procedure; all the patients underwent coaxial placement of an additional stent with good results. One patient showed recurrence of obstruction due to tumor in-growth, and this was treated by placement of a second stent. Two patients with stent placement in the duodenum suffered from jaundice 26 days and 65 days, respectively, after their procedures. Placement of the newly designed complex expandable nitinol stent seems to be effective for the palliative treatment of malignant gastroduodenal obstructions. The new stent also seems to help overcome the

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

    Science.gov (United States)

    Beranek, J; Jaresova, H; Rytz, U

    2014-02-01

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

  9. Feasibility study for the investigation of Nitinol self-expanding stents by neutron techniques

    International Nuclear Information System (INIS)

    Rogante, M.; Pasquini, U.; Rosta, L.; Lebedev, V.

    2011-01-01

    In this paper, neutron techniques - in particular, small angle neutron scattering (SANS) and neutron diffraction (ND) - are considered for the non-destructive characterization of Nitinol artery stents. This roughly equiatomic (50Ni-50Ti at%) shape memory alloy (SMA) exhibits significant properties of superelasticity and biocompatibility that make it suitable to be typically used as smart material for medical implants and devices. Nitinol self-expanding artery stents, as permanent vascular support structures, supply an ideal option to bypass surgery, but they are submitted for the whole of patient's life to the dynamical stress of the artery pulsation and the aggression from the biological environment. These stents, consequently, can suffer from wear and fracture occurrence likely due to a variety of cyclic fatigue, overload conditions and residual stresses. Neutrons have recently become a progressively more important probe for various materials and components and they allow achieving information complementary to those obtained from the traditional microstructural analyses. The outputs from the preliminary works already carried out in this field consent to consider neutron techniques capable to contribute to the development of these crucial medical implants. The achievable results can yield trends adoptable in monitoring of the stent features. -- Research Highlights: → Neutron techniques can contribute to develop Nitinol self-expanding artery stents. → Neutrons investigations can help avoiding wear and fracture events in Nitinol stents. → Neutron techniques can yield trends adoptable in monitoring of Nitinol stent features. → SANS is able to perform a micro- and nano-scale characterization of Nitinol stents. → Neutron Diffraction helps assessing stresses due to the exercise in Nitinol stents.

  10. Evaluation of the 4-French Pulsar-18 Self-expanding Nitinol Stent in Long Femoropopliteal Lesions.

    Science.gov (United States)

    Lichtenberg, Michael; Hailer, Birgit; Kaeunicke, Matthias; Stahlhoff, Wilhelm-Friedrich; Boese, Dirk; Breuckmann, Frank

    2014-01-01

    To evaluate the patency and the freedom of target lesion revascularization of the 4-French Pulsar-18 self-expandable (SE) nitinol stent for the treatment of long femoropopliteal occlusive disease in a two-center, prospective, all-comers registry with a follow-up period of 12 months. This registry enrolled 36 patients with symptomatic femoropopliteal long lesions for recanalization and implantation of the 4-French Pulsar-18 SE nitinol stent. Routine follow-up examination including duplex ultrasound was performed after 6 and 12 months. Primary patency was defined as no binary restenosis on duplex ultrasound (Peak systolic velocitiy ration (PSVR) Pulsar-18 SE nitinol stent for endovascular intervention of femoropopliteal disease with a mean lesion length of 182.3 ± 51.8 mm showed promising primary patency and fTLR rates after 6 and 12 months. Diabetes and renal insufficiency had no negative impact on the patency rate.

  11. Polyurethane-Covered Self-expandable Nitinol Stent for Malignant Biliary Obstruction: Preliminary Results

    International Nuclear Information System (INIS)

    Han, Young-Min; Hwang, Seung-Bae; Lee, Soo-Teik; Lee, Jeong-Min; Chung, Gyung-Ho

    2002-01-01

    Purpose: To evaluate the immediate and long-term results in ten patients with malignant biliary obstruction using a polyurethane-covered, self-expandable nitinol stent.Methods: A nitinol stent, fully covered with high-elasticity polyurethane, with an unconstrained diameter of 10 mm and a total length of 60-80 mm, was placed transhepatically under fluoroscopic guidance in ten patients. The length of the biliary obstruction varied between 30-50 mm. The follow-up examination included a clinical assessment, serum bilirubin measurement, and ultrasound examinations at one-month intervals in all patients. Results: Initial stent deployment was successful in eight patients. Two patients experienced proximal migration,which was solved by insertion of two, uncovered Wallstents. One patient had the stent removed after two weeks because of severe nausea and vomiting. One patient had delayed migration of the covered stent after 40 weeks. The follow-up duration was 3-40 weeks (Mean: 16.9 weeks). Seven patients died(3-26 weeks) and three patients survived (24-40 weeks). The bilirubin measurements in all patients had significantly decreased one week after stent insertion. The levels of amylase and lipase had did not increase after stent insertion. Conclusions: Apolyurethane-covered, self-expandable nitinol stent can be used effectively and safely in the treatment of malignant biliary obstruction. The preliminary results are favorable, but there is a need for further large studies to determine both long-term survival and patency

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Han, Young-Min; Kwak, Hyo-Sung; Jin, Gong-Yong; Lee, Seung-Ok; Chung, Gyung-Ho [Chonbuk National University Medical School and Hospital, Chonju (Korea, Republic of)

    2007-10-15

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

  14. Self-expanding nitinol stents for treatment of infragenicular arteries following unsuccessful balloon angioplasty

    International Nuclear Information System (INIS)

    Tepe, Gunnar; Heller, Stephan; Wiskirchen, Jakub; Fischmann, Arne; Claussen, Claus D.; Zeller, Thomas; Coerper, Stephan; Beckert, Stefan; Balletshofer, Bernd

    2007-01-01

    The feasibility of self-expanding nitinol stents for treatment of infragenicular arteries following unsuccessful balloon angioplasty was assessed. Options for lower limb percutaneous revascularization are limited, especially for complex vessel obstruction. Depending on the lesion and the experience of the interventionalist, the failure rate of balloon angioplasty (PTA) ranges between 10 and 40%. Until recently, no self-expanding stent for the use in the infragenicular arteries was available. This is the first report of the results for 18 consecutive patients who received 4F sheath compatible self-expanding nitinol stents following unsuccessful PTA or early restenosis. Twenty-four stents were implanted in 21 lesions for various indications residual stenosis >50% due to heavy calcification, flow-limiting dissection, occluding thrombus resistant to thrombolyis, thrombaspiration, and PTA, and early restenosis after previous PTA. Stent implantation was feasible in all cases. No complications occurred. After the stent implantation, all primarily unsuccessful interventions could be transformed into successful procedures with no residual stenosis >30% in any case. After 6 ± 2 months, two of the 18 patients died, and 14 of the 16 remaining patients improved clinically. At follow-up, the patency could be assessed in 14 stented arteries. Three stents were occluded, one stent showed some neointimal hyperplasia (50-70% restenosis), the remaining ten stents showed no restenosis (0-30%). The use of self-expanding nitinol stents in tibioperoneal and popliteal arteries is a safe and feasible option for the treatment of unsuccessful PTA. The 6-months patency is high. (orig.)

  15. Comparison of visibility for four self-expanding nitinol bare stents in vitro

    International Nuclear Information System (INIS)

    Wiesinger, Benjamin; Stutz, Alexander; Schmehl, Joerg; Groezinger, Gerd; Claussen, Claus Detlef; Wiskirchen, Jakub

    2012-01-01

    Background Sufficient radiopacity of stents is a prerequisite for safe interventions and minimization of the radiation dose for the patient and the interventionist. Modern nitinol stents are considered less radiopaque compared to formerly used stents. Purpose To evaluate the objective detection rate (ODR) and the subjective radiopacity score (SRS) of four self-expanding nitinol stents with their markers on a phantom human pelvis. Material and Methods We evaluated the ODR (as a percentage of correctly identified stents) and the SRS (on a scale from 0 = not visible to 4 = excellent visibility) for four self-expanding nitinol stents (SinusSuperflex, SMART, Luminexx, Zilver) with 8 mm diameter and 40 mm length. Stents were placed on a phantom human pelvis and images of the stents were taken in four different positions (right and left lumbosacral joint and near the right and left limbus acetabuli) using the following modes: spotfilm, pulsed fluoroscopy (4, 7.5, 15, and 30 pulses/min) and at three different digital magnification modes. Dose area products (DAPs) were assessed. Results ODR and SRS, respectively, were significantly increased for the SMART stent compared to all other tested stents (P < 0.05): SMART 93.53% and 2.43, SinusSuperflex 90.81% and 2.21, Luminexx 90.39% and 2.20, and Zilver 89.28% and 2.21. ODR was significantly reduced in position 3 where the bone overlap was more pronounced for all stents (detection rates 77.14-79.56%). An increase in magnification significantly improved the ODR and SRS for all stents (70.33-99.25% and 1.07-3.28, respectively, P < 0.05). Increased pulsing frequency did not improve the ODR of the various stents but did increase the DAP. Conclusion The SMART stent had the best overall performance. In the presence of bone overlap, all self-expanding nitinol stents had poor results. Increased pulsing frequency did not improve ODR or SRS but did increase the DAP. Use of digital magnification modes had no effect on DAP increasing ODR

  16. Dysphagia with malignant stricture of esophagogastric junction: treatment with self-expandable nitinol stent

    International Nuclear Information System (INIS)

    Lee, Choon Hyeong; Oh, Joo Hyeong; Yoon, Yup

    1995-01-01

    To evaluate the effectiveness, patency and safety of a self-expandable nitinol stent for palliative treatment of malignant stricture of gastroesophageal junction. An esophageal stent was inserted in five consecutive patients with malignant stricture of esophagogastric junction. Histologically, four cases were adenocarcinoma, and one was squamous cell carcinoma. The location and severity of stricture were evaluated with gastrografin just before stent insertion. In one patient with past subtotal gastrectomy, esophagography revealed fistulous fract at stricture site. No technical failure or procedural complications occurred, and improvement of dysphagia was noted in all patients soon after stent insertion. On follow up esophagograms performed 3 to 7 days after stent insertion, all stents were completely expanded and unchanged in positions. In one patient with fistulous connection at stricture site, esophagogram immediately after the procedure revealed complete occlusion of the fistula. Three patients died within 4, 7 and 8 consecutive months after stent insertion. Two patients are alive maintaining adequate body weight and passing most diet. Seft-expandable nitinol stent with it's good longitudinal flexibility and efficient radial force was effective in the palliative treatment of dysphagia in patient with malignant stricture at esophagogastric junction

  17. Dysphagia with malignant stricture of esophagogastric junction: treatment with self-expandable nitinol stent

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Choon Hyeong; Oh, Joo Hyeong; Yoon, Yup [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1995-02-15

    To evaluate the effectiveness, patency and safety of a self-expandable nitinol stent for palliative treatment of malignant stricture of gastroesophageal junction. An esophageal stent was inserted in five consecutive patients with malignant stricture of esophagogastric junction. Histologically, four cases were adenocarcinoma, and one was squamous cell carcinoma. The location and severity of stricture were evaluated with gastrografin just before stent insertion. In one patient with past subtotal gastrectomy, esophagography revealed fistulous fract at stricture site. No technical failure or procedural complications occurred, and improvement of dysphagia was noted in all patients soon after stent insertion. On follow up esophagograms performed 3 to 7 days after stent insertion, all stents were completely expanded and unchanged in positions. In one patient with fistulous connection at stricture site, esophagogram immediately after the procedure revealed complete occlusion of the fistula. Three patients died within 4, 7 and 8 consecutive months after stent insertion. Two patients are alive maintaining adequate body weight and passing most diet. Seft-expandable nitinol stent with it's good longitudinal flexibility and efficient radial force was effective in the palliative treatment of dysphagia in patient with malignant stricture at esophagogastric junction.

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

    International Nuclear Information System (INIS)

    Lastovickova, Jarmila; Peregrin, Jan H.

    2008-01-01

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

  19. Transcatheter aortic value implantation with self-expandable nitinol valved stent: an experimental study in sheep

    International Nuclear Information System (INIS)

    Jiang Haibin; Huang Xinmiao; Bai Yuan

    2011-01-01

    Objective: to determine the feasibility and safety of transcatheter aortic valve implantation with domestic self-expandable nitinol valved stent in experimental sheep. Methods: A fresh pig pericardium was cross-linked with a 0.6% glutaraldehyde solution for 36 hours and then sutured on a nitinol self-expandable stent. Ten healthy sheep of (46.00±2.60) kg body weight were chosen for the study. Under general anesthesia, the device was delivered through catheter into the native aortic valve of the sheep via the femoral artery or abdominal aorta. The animals were followed up for three months. Results: Six devices were successfully delivered at the desired position in six sheep with no occurrence of complications. Angiographic and hemodynamic studies confirmed that the stents were fixed at correct position with competent valve function immediately and 90 days after the procedure. Technical failure or fatal complications occurred in the remaining four sheep. Conclusion: Implantation of a domestic nitinol self-expandable stent at the aortic valve position through a transcatheter approach is feasible in experimental sheep. (authors)

  20. Treatment of Benign Tracheal Stenosis Utilizing Self-Expanding Nitinol Stents

    International Nuclear Information System (INIS)

    Sesterhenn, Andreas M.; Wagner, Hans-Joachim; Alfke, Heiko; Werner, Jochen A.; Lippert, Burkard M.

    2004-01-01

    We assessed the results of self-expanding metallic stent insertion into benign proximal tracheal stenosis in patients not appropriate or unfit for surgical repair. Proximal benign tracheal stenoses had occurred in 11 patients (7 men, 4 women, mean age 68.8 years) after long-time intubation (n = 6), tracheostomy (n = 4), or chondropathia (n = 1). Fourteen self-expanding nitinol stents were placed in the patients under general anesthesia with endoscopical and fluoroscopical guidance. Stent insertion was successful in all cases and led to immediate relief of the morphological and functional airway obstruction. No immediate complications were noted. During the mean follow-up period of 67.5 weeks we observed one recurrent dyspnea 3 months after implantation and granuloma formation at the stent insertion site in another patient. Both complications were successfully treated with additional stent insertion in one case and laser resection of granulomas in the other. Self-expanding nitinol stents should be considered for the treatment of benign proximal tracheal obstruction in selected patients for whom surgical repair is contraindicated

  1. Insertion of Self-Expandable Nitinol Stents Without Previous Balloon Angioplasty Reduces Restenosis Compared with PTA Prior to Stenting

    International Nuclear Information System (INIS)

    Harnek, Jan; Zoucas, Evita; Stenram, Unne; Cwikiel, Wojciech

    2002-01-01

    Purpose: To compare the development of intimal hyperplasia after deployment of a self-expanding nitinol stent with and without previous percutaneous transluminal balloon angioplasty (PTA), with the results after PTA alone. Methods: In nine healthy pigs, the iliac arteries were divided into three groups: group 1 (n = 6 arteries) was treated with PTA; group 2 n 6)with insertion of self-expanding stents after PTA; and group 3 (n = 6) with stent insertion without previous PTA. After 8 weeks the vessels were examined with intravascular ultrasonography,histologic examination and morphometric analysis. Results: Although the injury index in group 1 (0.17± 0.57) was lower (p <0.05) than in group 2 (0.26 ± 0.06) and group 3 (0.26 ± 0.08), PTA-treated arteries showed significantly (p <0.05) reduced mean luminal gain (0.53 ± 2.84) compared with arteries treated with PTA prior to stenting (2.58 ± 1.38) and compared with stenting alone (4.65 ±5.34). Stenting after PTA resulted in a higher (p<0.05) restenosis index (2.63 ± 1.06) compared with stenting without PTA (1.35 ± 0.59). Group 2 also had a significantly thicker intimap <0.05) and 83% and 74% higher intima/mediaratio (p <0.05) compared with groups 1 and 3, respectively. Conclusion: Insertion of a self-expandable nitinol stent without previous PTA results in less intimalhyperplasia than if PTA is performed prior to stenting, suggesting that direct stenting can be used in angioplasty sessions with a favorable outcome

  2. Physical properties of a new type of self-expandable nitinol stent

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Soo [Seoul Health College, Seoul (Korea, Republic of); Kim, Tae Hyung; Song, Sang Woo; Kang, Seong Gwon; Huh, Soo Jin; Song, Ho Young [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of); Kim, Eun Sang [Stentech, Inc., Seoul (Korea, Republic of); Kim, Cheol Saeng [Solco Surgical Instruments Co., Ltd, Seoul (Korea, Republic of)

    1999-08-01

    To study the new physical properties including hoop strength and flexibility of a newly developed nitinol stent. The new stent was made of a single nitinol wire 0.15 - 0.25 mm in diameter. This was wound around a cylindrical metallic jig with a constant angle to the longitudinal direction, and stents which winding were constructed. Hoop strength of the stents was measured with a spring gauge and compared with that of Wallstent and Hanaro stents. The flexibility of the new stent was evaluated on the basis of changes in stent diameter when bent in the direction of 180 deg Hoop strength of the new nitinol stent was proportional to 3.8 ({+-}0.3)-th power of the wire thickness. A greater number of wires on a lateral cut surface or a greater number of longitudinal windings also resulted in increased strength. However, the former caused an increase in total wire area and the latter resulted increased stent length when compressed. Hoop strength of the new nitinol stent was superior to that of Wallstent and Hanaro stents, and stent diameter did not decrease when the stent was bent in the direction of 180 degrees. Hoop strength of the new nitinol stent was most significantly affected by wire thickness. The stent was very flexible and thus seemed suitable for an angled lumen.

  3. Bleeding after expandable nitinol stent placement in patients with esophageal and upper gastrointestinal obstruction: incidence, management, and predictors.

    Science.gov (United States)

    Oh, Se Jin; Song, Ho-Young; Nam, Deok Ho; Ko, Heung Kyu; Park, Jung-Hoon; Na, Han Kyu; Lee, Jong Jin; Kang, Min Kyoung

    2014-11-01

    Placement of self-expandable nitinol stents is useful for the treatment of esophageal and upper gastrointestinal (GI) obstruction. However, complications such as stent migration, tumor overgrowth, and bleeding occur. Although stent migration and tumor overgrowth are well documented in previous studies, the occurrence of bleeding has not been fully evaluated. To evaluate the incidence, management strategies, and predictors of bleeding after placement of self-expandable nitinol stents in patients with esophageal and upper GI obstruction. We retrospectively reviewed the medical records and results of computed tomography and endoscopy of 1485 consecutive patients with esophageal and upper GI obstructions who underwent fluoroscopically guided stent placement. Bleeding occurred in 25 of 1485 (1.7%) patients 0 to 348 days after stent placement. Early stent-related bleeding occurred in 10 patients (40%) and angiographic embolization was used for 5/10. Late bleeding occurred in 15 patients (60%) and endoscopic hemostasis was used for 7/15. Twenty-two of 25 (88%) patients with bleeding had received prior radiotherapy and/or chemotherapy. Bleeding is a rare complication after placement of expandable nitinol stents in patients with esophageal and upper GI obstruction, but patients with early bleeding may require embolization for control. Care must be exercised on placing stents in patients who have received prior radiotherapy or chemotherapy. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  4. Self-expandable polytetrafluoroethylene (PTFE)-covered nitinol stent for the palliative treatment of malignant biliary obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Oong; Jung, Gyoo Sik; Han, Byung Hoon; Shin, Dong Hoon [Gospel Hospital, College of Medicine, Kosin University, Busan (Korea, Republic of); Ko, Ji Ho [Masan Samsung Medical Center, Sungkyunkwan University School of Medicine, Masan (Korea, Republic of)

    2008-06-15

    We wanted to determine the technical and clinical efficacy of placing a self-expandable PTFE-covered nitinol stent for the management of inoperable malignant biliary obstruction. Thirty six patients with inoperable malignant biliary obstructions were treated by placement of self-expandable PTFE-covered nitinol stents (S and G Biotech Corporation, Seongnam, Korea). Clinical evaluation was done with assessment of the serum bilirubin and alkaline phosphatase levels, which were measured before and after stent placement within 1 week, at 1 month and at 3 months. The patient survival rate and stent patency rate were calculated with performing Kaplan-Meier survival analysis. Successful stent placement was achieved in all the patients without procedure-related complication. Pancreatitis as an early complication occurred in two cases. The serum bilirubin and alkaline phosphatase levels were significantly decreased after the procedure. During the follow-up, recurrent obstructive jaundice occurred in six cases; stent migration occurred in four cases and tumor overgrowth occurred in two cases. The survival rates were 97%, 80%, 67% and 59% at 1, 3, 6 and 9 months, respectively. The stent patency rates were 96%, 92%, 86% and 86% at 1, 3, 6 and 9 months, respectively. Self-expandable PTFE-covered nitinol stent placement seems to be technically feasible and effective for the palliative treatment of malignant biliary obstruction.

  5. Self-expandable polytetrafluoroethylene (PTFE)-covered nitinol stent for the palliative treatment of malignant biliary obstruction

    International Nuclear Information System (INIS)

    Yoo, Oong; Jung, Gyoo Sik; Han, Byung Hoon; Shin, Dong Hoon; Ko, Ji Ho

    2008-01-01

    We wanted to determine the technical and clinical efficacy of placing a self-expandable PTFE-covered nitinol stent for the management of inoperable malignant biliary obstruction. Thirty six patients with inoperable malignant biliary obstructions were treated by placement of self-expandable PTFE-covered nitinol stents (S and G Biotech Corporation, Seongnam, Korea). Clinical evaluation was done with assessment of the serum bilirubin and alkaline phosphatase levels, which were measured before and after stent placement within 1 week, at 1 month and at 3 months. The patient survival rate and stent patency rate were calculated with performing Kaplan-Meier survival analysis. Successful stent placement was achieved in all the patients without procedure-related complication. Pancreatitis as an early complication occurred in two cases. The serum bilirubin and alkaline phosphatase levels were significantly decreased after the procedure. During the follow-up, recurrent obstructive jaundice occurred in six cases; stent migration occurred in four cases and tumor overgrowth occurred in two cases. The survival rates were 97%, 80%, 67% and 59% at 1, 3, 6 and 9 months, respectively. The stent patency rates were 96%, 92%, 86% and 86% at 1, 3, 6 and 9 months, respectively. Self-expandable PTFE-covered nitinol stent placement seems to be technically feasible and effective for the palliative treatment of malignant biliary obstruction

  6. Bronchobiliary Fistula Treated by Self-expanding ePTFE-Covered Nitinol Stent-Graft

    International Nuclear Information System (INIS)

    Gandini, Roberto; Konda, Daniel; Tisone, Giuseppe; Pipitone, Vincenzo; Anselmo, Alessandro; Simonetti, Giovanni

    2005-01-01

    A 71-year-old man, who had undergone right hepatectomy extended to the caudate lobe with terminolateral Roux-en-Y left hepatojejunostomy for a Klatskin tumor, developed bilioptysis 3 weeks postoperatively due to bronchobiliary fistula. Percutaneous transhepatic cholangiography revealed a non-dilated biliary system with contrast medium extravasation to the right subphrenic space through a resected anomalous right posterior segmental duct. After initial unsuccessful internal-external biliary drainage, the fistula was sealed with a VIATORR covered self-expanding nitinol stent-graft placed with its distal uncovered region in the hepatojejunal anastomosis and the proximal ePTFE-lined region in the left hepatic duct. A 10-month follow-up revealed no recurrence of bilioptysis and confirmed the complete exclusion of the bronchobiliary fistula

  7. Endovascular repair of arterial iliac vessel wall lesions with a self-expandable nitinol stent graft system.

    Directory of Open Access Journals (Sweden)

    Birger Mensel

    Full Text Available To assess the therapeutic outcome after endovascular repair of iliac arterial lesions (IALs using a self-expandable Nitinol stent graft system.Between July 2006 and March 2013, 16 patients (13 males, mean age: 68 years with a self-expandable Nitinol stent graft. A total of 19 lesions were treated: nine true aneurysms, two anastomotic aneurysms, two dissections, one arteriovenous fistula, two type 1B endoleaks after endovascular aneurysm repair, one pseudoaneurysm, and two perforations after angioplasty. Pre-, intra-, and postinterventional imaging studies and the medical records were analyzed for technical and clinical success and postinterventional complications.The primary technical and clinical success rate was 81.3% (13/16 patients and 75.0% (12/16, respectively. Two patients had technical failure due to persistent type 1A endoleak and another patient due to acute stent graft thrombosis. One patient showed severe stent graft kinking on the first postinterventional day. In two patients, a second intervention was performed. The secondary technical and clinical success rate was 87.5% (14/16 and 93.8% (15/16. The minor complication rate was 6.3% (patient with painful hematoma at the access site. The major complication rate was 6.3% (patient with ipsilateral deep vein thrombosis. During median follow-up of 22.4 months, an infection of the aneurysm sac in one patient and a stent graft thrombosis in another patient were observed.Endovascular repair of various IALs with a self-expandable Nitinol stent graft is safe and effective.

  8. USE OF COVERED SELF-EXPANDABLE NITINOL STENT FOR ANASTOMOTIC BILIARY STRUCTURE MANAGEMENT AFTER LIVER TRANSPLANTATION: THE FIRST EXPERIENCE

    Directory of Open Access Journals (Sweden)

    M. N. Kornilov

    2013-01-01

    Full Text Available Aim. The aim of this study focuses on the first experience with self-expandable stents, analysis of its efficacy and safety in the treatment of anastomotic strictures after liver transplantation. Materials and methods. There’re 136 liver transplantations performed from 2004 till 2012. To correct anastomotic strictures we’ve used only the self-expandable coated nitinol stent. We performed stenting in 7 recipient. Result. In 131 liver transplant recipients incidence of biliary strictures has been 5.3%. All of 5 patients have been managed by retrograde or antegrade way. Conclusion. Our first experience demonstrate efficacy and safety of the used tecniques up to 24 months. The analysis of more long-term results is required. 

  9. Temporary placement of covered retrievable expandable nitinol stents with barbs in high-risk surgical patients with benign prostatic hyperplasia: work in progress.

    Science.gov (United States)

    Kim, Choung-Soo; Song, Ho-Young; Jeong, In Gab; Yeo, Hyun Jin; Kim, Eun-Young; Park, Jung-Hoon; Yoon, Chang Jin; Paick, Sung Hyun; Park, Sang Woo; Bae, Jae-Ik; Won, Je Hwan

    2011-10-01

    To report the use of a newly constructed, covered, retrievable, expandable nitinol stent with barbs to overcome the problem of stent migration associated with conventional covered prostatic expandable stents and to evaluate prospectively the technical feasibility and clinical effectiveness of the stents in patients with benign prostatic hyperplasia (BPH). A covered retrievable expandable nitinol stent with four barbs was placed with use of an 18-F stent delivery system in seven consecutive patients with symptomatic BPH who had high operative risks. Age range of patients was 62-83 years (mean 74 years). In cases in which the stent migrated, it was replaced with a stent with eight barbs. The stents were routinely removed 4 months after placement using a 21-F stent removal set. Stent placement was technically successful and well tolerated in six of the seven patients. The remaining patient needed a second stent placement after removal of the first stent. The stent with four barbs migrated into the urinary bladder in four patients (57%); three of these patients received a second stent with eight barbs with good results, and the fourth patient did not need further treatment because his symptoms improved. Routine removal of the stent 4 months after placement was performed in three of the seven patients with good results. Retrievable stents with eight barbs seem to overcome the problem of stent migration associated with conventional prostatic expandable stents. Preliminary results suggest that stents with barbs are both feasible and effective in patients with BPH. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

  10. Endovascular treatment of intrahepatic inferior vena cava obstruction from malignant hepatocellular tumor thrombus utilizing Luminexx self-expanding nitinol stents

    International Nuclear Information System (INIS)

    Stambo, Glenn W.; Leto, John; George, Christopher; Van Epps, Kelly; Woeste, Troy; Berlet, Mathew

    2008-01-01

    Inferior vena cava (IVC) obstruction is a well-described clinical entity. Most IVC obstructions from malignant neoplasms are a direct result of tumor compression [Oviedo J, Cerda S. Vascular invasion by hepatocellular carcinoma. Arch Pathol Lab Med 2001;125: 454-5; Furui S, Sawada S, et al. Gianturco stent placement in malignant caval obstruction: analysis of factors for predicting the outcome. Radiology 1995;195:147-52; Fletcher WS, Lakin PC, et al. Results of treatment of inferior vena cava syndrome with expandable metallic stents. Arch Surg 1998;133:935-8]. The symptoms of IVC obstruction include progressive ascites, scrotal edema and lower body edema. These constellations of symptoms are described as IVC syndrome and are devastating to a patient with end-stage cancer. We describe a palliative therapy utilizing Luminexx nitinol self-expanding stents to treat intracaval hepatoma thrombus obstructing the IVC. The procedure is rapidly performed, technically reliable, and has essentially no morbidity or mortality. This procedure can be performed in the interventional radiology suite with excellent results resolving the IVC syndrome soon after placement of the stents. We believe endovascular stenting as an excellent palliative therapy for patients with IVC syndrome and should be the treatment of choice for caval obstructions due to intraluminal tumor thrombus

  11. Endovascular treatment of intrahepatic inferior vena cava obstruction from malignant hepatocellular tumor thrombus utilizing Luminexx self-expanding nitinol stents

    Energy Technology Data Exchange (ETDEWEB)

    Stambo, Glenn W. [Division of Vascular and Interventional Radiology, Department of Radiology, St. Joseph' s Hospital and Medical Center, 4516 North Armenia Avenue, Tampa, FL 33603 (United States)], E-mail: xraydoc2@yahoo.com; Leto, John [Division of Vascular and Interventional Radiology, Department of Radiology, St. Joseph' s Hospital and Medical Center, 3001 W. Dr. Martin Luther King Jr. Blvd., Tampa, FL 33607 (United States); George, Christopher [Department of Hematology and Oncology, St. Joseph' s Hospital and Medical Center, 4301 W. Habana Avenue, Suite 1, Tampa, FL 33607 (United States); Van Epps, Kelly; Woeste, Troy; Berlet, Mathew [Division of Vascular and Interventional Radiology, Department of Radiology, St. Joseph' s Hospital and Medical Center, 4516 North Armenia Avenue, Tampa, FL 33603 (United States)

    2008-05-15

    Inferior vena cava (IVC) obstruction is a well-described clinical entity. Most IVC obstructions from malignant neoplasms are a direct result of tumor compression [Oviedo J, Cerda S. Vascular invasion by hepatocellular carcinoma. Arch Pathol Lab Med 2001;125: 454-5; Furui S, Sawada S, et al. Gianturco stent placement in malignant caval obstruction: analysis of factors for predicting the outcome. Radiology 1995;195:147-52; Fletcher WS, Lakin PC, et al. Results of treatment of inferior vena cava syndrome with expandable metallic stents. Arch Surg 1998;133:935-8]. The symptoms of IVC obstruction include progressive ascites, scrotal edema and lower body edema. These constellations of symptoms are described as IVC syndrome and are devastating to a patient with end-stage cancer. We describe a palliative therapy utilizing Luminexx nitinol self-expanding stents to treat intracaval hepatoma thrombus obstructing the IVC. The procedure is rapidly performed, technically reliable, and has essentially no morbidity or mortality. This procedure can be performed in the interventional radiology suite with excellent results resolving the IVC syndrome soon after placement of the stents. We believe endovascular stenting as an excellent palliative therapy for patients with IVC syndrome and should be the treatment of choice for caval obstructions due to intraluminal tumor thrombus.

  12. Self-Expanding Nitinol Renal Artery Stents: Comparison of Safety and Efficacy of Bare Versus Polyzene-F Nanocoated Stents in a Porcine Model

    International Nuclear Information System (INIS)

    Kurz, P.; Stampfl, U.; Christoph, P.; Henn, C.; Satzl, S.; Radeleff, B.; Berger, I.; Richter, G. M.

    2011-01-01

    Objective: To investigate the safety and efficacy of a Polyzene-F nanocoat on new low-profile self-expandable nitinol stents in minipig renal arteries. Materials and Methods: Ten bare nitinol stents (BNS) and 10 stents coated with a 50 nm-thin Polyzene-F coating were randomly implanted into renal arteries of 10 minipigs (4- and 12-week follow-up, 5 animals/group). Thrombogenicity, on-stent surface endothelialization, vessel wall injury, late in-stent stenosis, and peristrut vessel wall inflammation were determined by quantitative angiography and postmortem histomorphometry. Results: In 6 of 10 BNS, >50% stenosis was found, but no stenosis was found in stents with a nanothin Polyzene-F coating. Histomorphometry showed a statistically significant (p < 0.05) different average maximum luminal loss of 55.16% ± 8.43% at 12 weeks in BNS versus 39.77% ± 7.41% in stents with a nanothin Polyzene-F coating. Stents with a nanothin Polyzene-F coating had a significantly (p < 0.05) lower inflammation score after 12 weeks, 1.31 ± 1.17 versus 2.17 ± 0.85 in BNS. The results for vessel wall injury (0.6 ± 0.58 for Polyzene-F-coated stents; 0.72 ± 0.98 for BNS) and re-endothelialization, (1.16 ± 0.43 and 1.23 ± 0.54, respectively) were not statistically significant at 12-week follow-up. No thrombus deposition was observed on the stents at either follow-up time point. Conclusion: Nitinol stents with a nanothin Polyzene-F coating successfully decreased in-stent stenosis and vessel wall inflammation compared with BNS. Endothelialization and vessel wall injury were found to be equal. These studies warrant long-term pig studies (≥120 days) because 12 weeks may not be sufficient time for complete healing; thereafter, human studies may be warranted.

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

    Science.gov (United States)

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

    2016-06-25

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

  14. Initial and mid-term results of a 4F compatible self-expanding low strut profile nitinol stent in the superficial femoral artery

    International Nuclear Information System (INIS)

    Muehlenbruch, G.; Brock, H.; Das, M.; Hohl, C.; Mahnken, A.H.; Wildberger, J.; Guenther, R.W.; Haage, P.

    2007-01-01

    Purpose: To evaluate the initial and mid-term results of a new self-expanding low strut profile nitinol stent for treatment of atherosclerotic lesions stenoses and occlusions in the superficial femoral artery (SFA). Materials and Methods: In 8 patients (4 male, 4 female, mean age 74.8 ± 8.8 years) with SFA lesions and non-satisfying results after PTA treatment alone, 10 self-expanding nitinol Xpert stents were deployed via a 4 F sheath. Stent characteristics and handling were graded by the interventionalist. Fontaine classification, duplex flow measurements and ankle brachial index (ABI) at rest and stress were taken prior and one day after stent placement. Patients were followed 3, 6 and 12 months after the procedure obtaining the same parameters at each appointment. Results: Initial stent treatment was successful in all patients. Stent handling and positioning were rated very good and safe. All patients improved clinically by at least one Fontaine stage (range before treatment: stage IIb to IV). The mean ABI at rest (stress) improved initially from 0.68 (0.70) to 1.07 (0.99). During a mean follow-up period of 8.3 months no case of clinically relevant in-stent stenosis was observed with stable values of ABI at rest and stress. (orig.)

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

    Directory of Open Access Journals (Sweden)

    Roberto Di Mitri

    2014-01-01

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

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

    Science.gov (United States)

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

    2017-09-01

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

  17. The influence of stent design on neointimal hyperplasia of an aortic stent covering the visceral arterial ostia: an experimental study in dogs using a self-expandable nitinol stent

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Yong Hu; Chung, Jin Wook; Choi, Seung Hong; Kim, Kwang Gi; Kim, Hyo Cheol; So, Young Ho; Jae, Hwan Jun; Lee, Whal; Park, Jae Hyung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2008-05-15

    To assess the influence of stent design [interlacing (type A) vs. crossing method (type B)] on neointimal hyperplasia using a self-expandable nitinol stent, which crosses the side branches of the abdominal aorta. In seven mongrel dogs, nitinol stents with type A and B intersections were placed in the abdominal aorta across the main branches: 4 Niti-Ms and 3 Niti-Ds. Two months after the stent placement, a DSA was performed for a stent patency evaluation, followed by the extraction of the aortas. The degree of neointimal formation along the wire was evaluated by calculating the area ratio of intimal hyperplasia (type A vs. B). A Student's t-test was employed to investigate the differences in the neointimal hyperplasia between blood types A and B. The total number of wire intersections overlain at the ostia branch ostia was 23 for type A and 36 for type B. The area ratio of the neointimal hyperplasia, for a given area, was 29.09 {+-} 10.82% (type A) and 13.80 {+-} 6.94% (type B) ({rho} < 0.0001)]. Furthermore, the area ratios of the neointimal hyperplasia per area of stent-wire in the given area were 138.38 {+-} 10.84% (type A). 87.58 {+-} 7.36% (type B) ({rho} = 0.0002). In conclusion the interlacing pattern vs. the crossing pattern showed a higher level of neointimal formation than the crossing pattern.

  18. The influence of stent design on neointimal hyperplasia of an aortic stent covering the visceral arterial ostia: an experimental study in dogs using a self-expandable nitinol stent

    International Nuclear Information System (INIS)

    Yin, Yong Hu; Chung, Jin Wook; Choi, Seung Hong; Kim, Kwang Gi; Kim, Hyo Cheol; So, Young Ho; Jae, Hwan Jun; Lee, Whal; Park, Jae Hyung

    2008-01-01

    To assess the influence of stent design [interlacing (type A) vs. crossing method (type B)] on neointimal hyperplasia using a self-expandable nitinol stent, which crosses the side branches of the abdominal aorta. In seven mongrel dogs, nitinol stents with type A and B intersections were placed in the abdominal aorta across the main branches: 4 Niti-Ms and 3 Niti-Ds. Two months after the stent placement, a DSA was performed for a stent patency evaluation, followed by the extraction of the aortas. The degree of neointimal formation along the wire was evaluated by calculating the area ratio of intimal hyperplasia (type A vs. B). A Student's t-test was employed to investigate the differences in the neointimal hyperplasia between blood types A and B. The total number of wire intersections overlain at the ostia branch ostia was 23 for type A and 36 for type B. The area ratio of the neointimal hyperplasia, for a given area, was 29.09 ± 10.82% (type A) and 13.80 ± 6.94% (type B) (ρ < 0.0001)]. Furthermore, the area ratios of the neointimal hyperplasia per area of stent-wire in the given area were 138.38 ± 10.84% (type A). 87.58 ± 7.36% (type B) (ρ = 0.0002). In conclusion the interlacing pattern vs. the crossing pattern showed a higher level of neointimal formation than the crossing pattern

  19. Nitinol Esophageal Stents: New Designs and Clinical Indications

    International Nuclear Information System (INIS)

    Strecker, Ernst-Peter; Boos, Irene; Vetter, Sylvia; Strohm, Michael; Domschke, Sigurd

    1996-01-01

    Purpose: To evaluate the clinical use of covered and noncovered, knitted nitinol stents in patients presenting new stent indications. Methods: Self-expandable, knitted nitinol stents were implanted in four patients for treatment of dysphagia. In two patients who had malignant strictures and had esophago-respiratory fistulae and in one patient with an esophagocutaneous fistula, polytetrafluoroethylene (PTFE)-covered stents were implanted. One patient received a noncovered stent, but a retrograde approach through a percutaneous endoscopic gastrostomy (PEG) fistula had to be chosen for recanalization of an esophageal occlusion. Two patients received stents for treatment of benign strictures. Results: Recanalization of the stricture and stent implantation were performed under fluoroscopic control without any procedure-related morbidity or mortality. Dysphagia improved in all patients and the esophageal fistulae could be sealed off by covered stents. During a maximum follow-up of 18 months, there was no stent migration or esophageal perforation. Complications observed were stent stenosis due to food impaction (1/4) and benign stent stenosis (2/2). Most complications could be treated by the interventional radiologist. Conclusion: Self-expandable, covered Nitinol stents provide an option for the treatment of dysphagia combined with esophageal fistulae. In combination with interventional radiology techniques, even complex strictures are accessible. For benign strictures, the value of stent treatment has not yet been proven

  20. PEACE I all-comers registry: patency evaluation after implantation of the 4-French Pulsar-18 self-expanding nitinol stent in femoropopliteal lesions.

    Science.gov (United States)

    Lichtenberg, Michael; Kolks, Oliver; Hailer, Birgit; Stahlhoff, Wilhelm-Friedrich; Tiefenbacher, Christiane; Nolte-Ernsting, Claus; Arjumand, Jawed; Wittenberg, Guenther

    2014-06-01

    To evaluate the 1-year patency of the 4-F Pulsar-18 self-expanding nitinol stent for treatment of femoropopliteal occlusive disease in a national, prospective, multicenter, all-comers registry. Between January and June 2012, the German PEACE I all-comers prospective registry enrolled 148 patients with symptomatic femoropopliteal lesions (Rutherford category 2-5) undergoing recanalization and implantation of the Pulsar-18 SE nitinol stent at 6 clinical centers. Thirty patients did not have the 12-month follow-up visit (18 declined reevaluation, 5 withdrew consent, and 7 died), leaving 118 patients (64 men; mean 71.9±9.6 age years) for the 1-year evaluation. The average lesion length was 111.5±71.4 mm, and 38 of the 118 lesions were classified as TASC II D. More than half the lesions (67, 56.7%) were chronic total occlusions (CTO). The popliteal segment was involved in 22 (18.7%) lesions. The mean stented length was 122.7±64.5 mm. Routine follow-up included duplex ultrasound at 6 and 12 months. Outcome measures were primary patency and no clinically driven target lesion revascularization (TLR) within 12 months. The overall primary patency rates after 6 and 12 months were 87.4% and 79.5%, respectively; in the popliteal segments, the rate was 71.4% after 12 months. The overall freedom from TLR was 93.2% after 6 months and 81% after 12 months. Ankle-brachial index, pain-free walking distance, and Rutherford category all improved significantly (pPulsar-18 self-expanding nitinol stent in femoropopliteal lesions averaging 111.5 mm long showed promising primary patency and freedom from TLR after 6 and 12 months. Diabetes had no negative impact on patency. Primary patency in the popliteal segments was acceptable at 12 months.

  1. Expandable stents.

    Science.gov (United States)

    Nesbitt, J C; Carrasco, H

    1996-05-01

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

  2. Long-Term Primary Patency Rate After Nitinol Self-Expandable Stents Implantation in Long, Totally Occluded Femoropopliteal (TASC II C & D) Lesions.

    Science.gov (United States)

    Elmahdy, Mahmoud Farouk; Buonamici, Piergiovanni; Trapani, Maurizio; Valenti, Renato; Migliorini, Angela; Parodi, Guido; Antoniucci, David

    2017-06-01

    Endovascular therapy for long femoropopliteal lesions using percutaneous transluminal balloon angioplasty or first-generation of peripheral stents has been associated with unacceptable one-year restenosis rates. However, with recent advances in equipment and techniques, a better primary patency rate is expected. This study was conducted to detect the long-term primary patency rate of nitinol self-expandable stents implanted in long, totally occluded femoropopliteal lesions TransAtlantic Inter-Society Census (TASC II type C & D), and determine the predictors of reocclusion or restenosis in the stented segments. The demographics, clinical, anatomical, and procedural data of 213 patients with 240 de novo totally occluded femoropopliteal (TASC II type C & D) lesions treated with nitinol self-expandable stents were retrospectively analysed. Of these limbs, 159 (66.2%) presented with intermittent claudication, while 81 (33.8%) presented with critical limb ischaemia. The mean-time of follow-up was 36±22.6 months, (range: 6.3-106.2 months). Outcomes evaluated were, primary patency rate and predictors of reocclusion or restenosis in the stented segments. The mean age of the patients was 70.9±9.3 years, with male gender 66.2%. Mean pre-procedural ABI was 0.45±0.53. One-hundred-and-seventy-five (73%) lesions were TASC II type C, while 65 (27%) were type D lesions. The mean length of the lesions was 17.9±11.3mm. Procedure related complications occurred in 10 (4.1%) limbs. There was no periprocedural mortality. Reocclusion and restenosis were detected during follow-up in 45 and 30 limbs respectively, and all were re-treated by endovascular approach. None of the patients required major amputation. Primary patency rates were 81.4±1.1%, 77.7±1.9% and 74.4±2.8% at 12, 24, and 36 months respectively. Male gender, severe calcification, and TASC II D lesion were independent predictors for reocclusion, while predictors of restenosis were DM, smoking and TASC II D lesions

  3. Investigation Of Interaction Between Nitinol Stent And A Vascular Plaque Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Recep Güneş

    2012-06-01

    Full Text Available In this study, the interaction between the Nitinol stent and the artery with plaque was investigated using finite element method. The occurring pressure values during the cardiac contraction (systolic and loosening (diastolic were applied as loading to the modeled system with Nitinol stent. In the light of the stress values, the suitability of the Nitinol stent in an artery with plaque was investigated. In the analysis, Nitinol stent was assumed to be shape memory alloy, and artery and plaque were assumed to behave linearly elastic. As a result, the stress and deformations in the plaque and artery due to the interference of Nitinol stent were discussed and concluded that the structure of artery with plaque can be expanded in accordance with Nitinol stent.

  4. A new self-expanding nitinol stent (Enterprise) for the treatment of wide-necked intracranial aneurysms: initial clinical and angiographic results in 31 aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Werner; Kuehne, Dietmar [Alfried Krupp Hospital, Department of Radiology and Neuroradiology, Essen (Germany); Bendszus, Martin; Solymosi, Laszlo [University of Wuerzburg, Department of Neuroradiology, Wuerzburg (Germany); Kis, Bernhard [University of Duisburg-Essen, Research Unit, Rheinische Kliniken Essen, Department of Psychiatry and Psychotherapy, Essen (Germany); Boulanger, Thierry [Centre Hospitalier of Luxembourg, Service of Neuroradiology, Luxembourg (Luxembourg)

    2007-07-15

    We report the results of a prospective clinical study using a new self-expanding nitinol stent (Enterprise) designed for the treatment of wide-necked intracranial aneurysms. We treated 31 saccular, wide-necked intracranial aneurysms in 30 patients. Ten aneurysms had recanalized after prior endovascular treatment without a stent, and 21 aneurysms had not been treated before. Stent deployment was successful in all procedures. Additional coil embolization was performed in all aneurysms. Initial complete angiographic occlusion was achieved in 6 aneurysms, a neck remnant was left in 18 aneurysms and there were 7 residual aneurysms. Angiographic follow-up examinations of 30 lesions after 6 months demonstrated 15 complete occlusions, 8 neck remnants and 7 residual aneurysms. One patient refused the 6-month angiographic follow-up. Spontaneous occlusion of the aneurysm had occurred in 14 patients, and 6 aneurysms showed recanalization. Four of these residual aneurysms were retreated. At the 6-month follow-up, 29 parent arteries were unaffected, whereas two parent vessels demonstrated minor asymptomatic narrowing at the stent site. Two patients experienced one or more possible or probable device-related serious adverse events during the 6-month follow-up period. There was no procedural morbidity or mortality at 6 months after the procedure. The reported results demonstrated the safety and feasibility of the Cordis Neurovascular Enterprise stent in the treatment of wide-necked intracranial aneurysms. Initial clinical and angiographic results are favorable. (orig.)

  5. Placement of a covered self-expandable nitinol stent for bile duct stricture that caused by ischemic injury after transcatheter arterial chemoembolization in a patient with hepatocellular carcinoma: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Kweon; Seo, Tae Seok; Cha, In Ho; Huh, Sik; Byun, Kwan Soo [Guro Hospital, Korea University College of Medicine, Seoul (Korea, Republic of)

    2008-10-15

    The authors report here on a case of focal stricture in the common hepatic duct that was caused by ischemic bile duct injury after repeat TACE procedures for hepatocellular carcinoma, and the patient was successfully treated with a covered self-expandable nitinol stent.

  6. Percutaneous treatment of adult isthmic aortic coarctation: acute and long-term clinical and imaging outcome with a self-expandable uncovered nitinol stent.

    Science.gov (United States)

    Kische, Stephan; D'Ancona, Giuseppe; Stoeckicht, Yannik; Ortak, Jasmin; Elsässer, Albrecht; Ince, Hüseyin

    2015-01-01

    To present perioperative and long-term results of percutaneous treatment of adult isthmic coarctation of the aorta by means of a self-expandable closed-web uncovered nitinol stent (Sinus-XL, Optimed, Esslingen, Germany). Preoperative, perioperative, and long-term clinical and computed tomographic angiography data were collected and analyzed prospectively. A total of 52 consecutive patients were treated with the Sinus-XL stent. Mean age was 36.6 (21-67) years, peak invasive trans-coarctation of the aorta gradient was 54.7 ± 9.9 mm Hg, and upper body hypertension unresponsive to medical treatment was present in all patients. Mean stent diameter and length were 24.2 mm (22-28 mm) and 70.4 mm (40-80 mm), respectively. Eight patients (15.4%) required coarctation of the aorta predilatation. All patients underwent poststent dilatation with a noncompliant balloon. Postoperative peak gradient (3.3 ± 2.5 mm Hg) was reduced significantly (P stent collapse and secondary migration and documented stability in aortic diameter (18.3 ± 2.7 mm). Thirty patients (57.7%) were completely weaned-off antihypertensive medications and their use dropped from 2.6 to 0.9 drugs/patient (P self-expandable uncovered stent is safe and durable. The peculiar stent design maintains adequate localized radial strength over time with minimal trauma on the adjacent aortic wall and negligible device-related complications. Blood pressure control optimization is immediate and persistent even at long-term follow-up. © 2015 American Heart Association, Inc.

  7. Esophageal leiomyoma in a dog causing esophageal distension and treated by transcardial placement of a self-expanding, covered, nitinol esophageal stent.

    Science.gov (United States)

    Robin, Elisabeth M; Pey, Pascaline B; de Fornel-Thibaud, Pauline; Moissonnier, Pierre H M; Freiche, Valérie

    2018-02-01

    CASE DESCRIPTION A 10-year-old spayed female Rottweiler was referred for evaluation because of a 2-month history of regurgitation and weight loss, despite no apparent change in appetite. The dog had received antiemetic and antacid treatment, without improvement. CLINICAL FINDINGS Physical examination revealed a low body condition score (2/5), but other findings were unremarkable. Diffuse, global esophageal dilatation was noted on plain thoracic radiographs, and normal motility was confirmed through videofluoroscopic evaluation of swallowing. Transhepatic ultrasonographic and CT examination revealed a circumferential, intraparietal lesion in the distal portion of the esophagus causing distal esophageal or cardial subobstruction and no metastases. Incisional biopsy of the lesion was performed, and findings of histologic examination supported a diagnosis of esophageal leiomyoma. TREATMENT AND OUTCOME In view of numerous possible complications associated with esophageal surgery, the decision was made to palliatively treat the dog by transcardial placement of a self-expanding, covered, nitinol esophageal stent under endoscopic guidance. Two weeks after stent placement, radiography revealed complete migration of the stent into the gastric lumen. Gastrotomy was performed, and the stent was replaced and fixed in place. Twenty-four months after initial stent placement, the dog had a healthy body condition and remained free of previous clinical signs. CLINICAL RELEVANCE Diffuse benign muscular neoplasia should be considered as a differential diagnosis for acquired esophageal dilatation in adult and elderly dogs. In the dog of this report, transcardial stent placement resulted in resolution of the clinical signs, with no apparent adverse effect on digestive function. The described procedure could be beneficial for nonsurgical treatment of benign esophageal tumors in dogs.

  8. Percutaneous therapy of inoperable biliary stenoses and occlusions with a new self-expanding nitinol stent (SMART)

    International Nuclear Information System (INIS)

    Zorger, N.; Lenhart, M.; Strotzer, M.; Paetzel, C.; Hamer, O.; Feuerbach, S.; Link, J.

    2002-01-01

    Objective: To evaluate the treatment of malignant biliary stenoses and occlusions using a new stent. Methods: In a prospective study, 25 patients with malignant obstructive jaundice were treated with SMART stents. The handling and the quality of stent expansion were documented. Stent function was assessed 2-4 days after intervention by cholangiography and laboratory tests. A follow-up was performed three months, after stent placement. Results: All lesions were treated successfully, with a total of 35 stents implanted. In 14 patients a further balloon dilatation was performed after stent placement (8-10 mm diameter/40-80 mm length). The mean serum bilirubin level decreased significantly from 11.6 mg/dl to 4.6 mg/dl after intervention (p [de

  9. The Primary Patency and Fracture Rates of Self-Expandable Nitinol Stents Placed in the Popliteal Arteries, Especially in the P2 and P3 Segments, in Korean Patients

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Il Soo; Chee, Hyun Keun; Park, Sang Woo; Yun, Ik Jin; Hwang, Jae Joon; Lee, Song Am; Kim, Jun Seok; Chang, Seong Hwan; Jung, Hong Geun [Konkuk University Hospital, Seoul (Korea, Republic of)

    2011-04-15

    We wanted to evaluate the status of self-expandable nitinol stents implanted in the P2 and P3 segments of the popliteal artery in Korean patients. We retrospectively analyzed 189 consecutive patients who underwent endovascular treatment for steno occlusive lesions in the femoropopliteal artery from July 2003 to March 2009, and 18 patients who underwent stent placement in popliteal arterial P2 and P3 segments were finally enrolled. Lesion patency was evaluated by ultrasound or CT angiography, and stent fracture was assessed by plain X-rays at 1, 3, 6 and 12 months and annually thereafter. At the 1-month follow-up, stent fracture (Type 2) was seen in one limb (up to P3, 1 of 18, 6%) and it was identified in seven limbs at the 3-month follow-up (Type 2, Type 3, Type 4) (n = 1: up to P2: n = 6: P3). At the 6-month follow-up, one more fracture (Type 1) (up to P3) was noted. At the 1-year follow-up, there were no additional stent fractures. Just four limbs (up to P2) at the 2-year follow-up did not have stent fracture. The primary patency was 94%, 61% and 44% at 1, 3 and 6 months, respectively, and the group with stent implantation up to P3 had a higher fracture rate than that of the group that underwent stenting up to P2 (p < 0.05). We suggest that stent placement up to the popliteal arterial P3 segment and over P2 in an Asian population can worsen the stent patency owing to stent fracture. It may be necessary to develop a stent design and structure for the Asian population that can resist the bending force in the knee joint

  10. Distribution of nickel after modified nitinol stent implantation in animals

    Science.gov (United States)

    Chepeleva, E.; Sergeevichev, D.; Lotkov, A.; Kashin, O.; Korobeynikov, A.; Kozyr, K.; Baystrukov, V.; Zubarev, D.; Kretov, E.; Pokushalov, E.

    2017-09-01

    Intravascular stenting of arteries in atherosclerotic lesions is one of the most frequently performed procedures in cardiovascular surgery today. Most stents are made of various stainless-steel alloys and other metals (such as nitinol). Nitinol is a biocompatible, superplastic and corrosion resistant material with an important feature of shape memory. However, the composition of this alloy includes nickel, which shows toxicity to the kidneys, liver, lungs, heart and other organs when it accumulates in the organism. In this research we investigated the nickel content in serum, urine and hair of the laboratory animals after implantation of nitinol stents treated with plasma ionic surface modification by silicon.

  11. Comparison of diamond-like carbon-coated nitinol stents with or without polyethylene glycol grafting and uncoated nitinol stents in a canine iliac artery model

    Science.gov (United States)

    Kim, J H; Shin, J H; Shin, D H; Moon, M-W; Park, K; Kim, T-H; Shin, K M; Won, Y H; Han, D K; Lee, K-R

    2011-01-01

    Objective Neointimal hyperplasia is a major complication of endovascular stent placement with consequent in-stent restenosis or occlusion. Improvements in the biocompatibility of stent designs could reduce stent-associated thrombosis and in-stent restenosis. We hypothesised that the use of a diamond-like carbon (DLC)-coated nitinol stent or a polyethylene glycol (PEG)-DLC-coated nitinol stent could reduce the formation of neointimal hyperplasia, thereby improving stent patency with improved biocompatibility. Methods A total of 24 stents were implanted, under general anaesthesia, into the iliac arteries of six dogs (four stents in each dog) using the carotid artery approach. The experimental study dogs were divided into three groups: the uncoated nitinol stent group (n = 8), the DLC-nitinol stent group (n = 8) and the PEG-DLC-nitinol stent group (n = 8). Results The mean percentage of neointimal hyperplasia was significantly less in the DLC-nitinol stent group (26.7±7.6%) than in the nitinol stent group (40.0±20.3%) (p = 0.021). However, the mean percentage of neointimal hyperplasia was significantly greater in the PEG-DLC-nitinol stent group (58.7±24.7%) than in the nitinol stent group (40.0±20.3%) (p = 0.01). Conclusion Our findings indicate that DLC-coated nitinol stents might induce less neointimal hyperplasia than conventional nitinol stents following implantation in a canine iliac artery model; however, the DLC-coated nitinol stent surface when reformed with PEG induces more neointimal hyperplasia than either a conventional or DLC-coated nitinol stent. PMID:21325363

  12. Endoscopically placed nitinol stents for pediatric tracheal obstruction.

    Science.gov (United States)

    Prasad, Mukesh; Bent, John P; Ward, Robert F; April, Max M

    2002-11-11

    To provide preliminary clinical data regarding endoscopically placed nitinol stents for children with tracheal obstruction as a temporizing measure to allow for trach tube decannulation while awaiting growth to allow for tracheal resection. This case series describes the experiences of two children (ages 5 and 15) who were dependent upon tracheotomy because of acquired tracheal obstruction. Both patients had combined tracheomalacia and tracheal stenosis. After failing tracheoplasty with rib graft augmentation both patients suffered from extensive tracheal disease, which was too long to allow for immediate tracheal resection. Endoscopic placement of nitinol stents in the obstructed tracheal segment using fluoroscopic guidance. All tracheotomy tubes were removed immediately after successful stent deployment with the patient still under general anesthesia. Four stents were placed in total. The first patient's initial stent was too narrow and was, therefore, removed and replaced at a later date with a larger diameter stent. The second patient experienced distal migration of his initial stent requiring stent removal and replacement at a later date. Both patients remain successfully decannulated (follow-up, 25 and 26 months) and are currently living more normal lives as they grow and await tracheal resection. Preliminary use of nitinol stents for pediatric tracheal obstruction has enabled successful decannulation in two children with complicated airways. Our results with this series of patients suggest that nitinol stents can be safely used in children as a temporizing measure until tracheal resection can be safely performed. With this approach children can live free from the hassles of trach care, social isolation and peer ridicule. Limited pediatric experience exists in the literature about nitinol stents. Thus, our experience with stent selection and placement will help others avoid problems encountered in this initial series. Copyright 2002 Elsevier Science Ireland

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

    Science.gov (United States)

    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.

  14. On the Mechanical Properties and Microstructure of Nitinol forBiomedical Stent Applications

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Scott W. [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    This dissertation was motivated by the alarming number of biomedical device failures reported in the literature, coupled with the growing trend towards the use of Nitinol for endovascular stents. The research is aimed at addressing two of the primary failure modes in Nitinol endovascular stents: fatigue-crack growth and overload fracture. The small dimensions of stents, coupled with their complex geometries and variability among manufacturers, make it virtually impossible to determine generic material constants associated with specific devices. Instead, the research utilizes a hybrid of standard test techniques (fracture mechanics and x-ray micro-diffraction) and custom-designed testing apparatus for the determination of the fracture properties of specimens that are suitable representations of self-expanding Nitinol stents. Specifically, the role of texture (crystallographic alignment of atoms) and the austenite-to-martensite phase transformation on the propagation of cracks in Nitinol was evaluated under simulated body conditions and over a multitude of stresses and strains. The results determined through this research were then used to create conservative safe operating and inspection criteria to be used by the biomedical community for the determination of specific device vulnerability to failure by fracture and/or fatigue.

  15. Percutaneous Palliation of Pancreatic Head Cancer: Randomized Comparison of ePTFE/FEP–Covered Versus Uncovered Nitinol Biliary Stents

    International Nuclear Information System (INIS)

    Krokidis, Miltiadis; Fanelli, Fabrizio; Orgera, Gianluigi; Tsetis, Dimitrios; Mouzas, Ioannis; Bezzi, Mario; Kouroumalis, Elias; Pasariello, Roberto; Hatzidakis, Adam

    2011-01-01

    The purpose of this study was to compare the clinical effectiveness of expanded polytetrafluoroethylene/fluorinated-ethylene-propylene (ePTFE/FEP)–covered stents with that of uncovered nitinol stents for the palliation of malignant jaundice caused by inoperable pancreatic head cancer. Eighty patients were enrolled in a prospective randomized study. Bare nitinol stents were used in half of the patients, and ePTFE/FEP–covered stents were used in the remaining patients. Patency, survival, complications, and mean cost were calculated in both groups. Mean patency was 166.0 ± 13.11 days for the bare-stent group and 234.0 ± 20.87 days for the covered-stent group (p = 0.007). Primary patency rates at 3, 6, and 12 months were 77.5, 69.8, and 69.8% for the bare-stent group and 97.5, 92.2, and 87.6% for the covered-stent group, respectively. Mean secondary patency was 123.7 ± 22.5 days for the bare-stent group and 130.3 ± 21.4 days for the covered-stent group. Tumour ingrowth occurred exclusively in the bare-stent group in 27.5% of cases (p = 0.002). Median survival was 203.2 ± 11.8 days for the bare-stent group and 247.0 ± 20 days for the covered-stent group (p = 0.06). Complications and mean cost were similar in both groups. Regarding primary patency and ingrowth rate, ePTFE/FEP–covered stents have shown to be significantly superior to bare nitinol stents for the palliation of malignant jaundice caused by inoperable pancreatic head cancer and pose comparable cost and complications. Use of a covered stent does not significantly influence overall survival rate; nevertheless, the covered endoprosthesis seems to offer result in fewer reinterventions and better quality of patient life.

  16. The underdilation of nitinol stents at TIPS implantation: Solution or illusion?

    Energy Technology Data Exchange (ETDEWEB)

    Mollaiyan, Ashkan [University Hospital, Department of Radiology, Hugstetterstrasse 55, 79106 Freiburg (Germany); Bettinger, Dominik [University Hospital, Department of Gastroenterology, Hugstetterstrasse 55, 79106 Freiburg (Germany); Berta-Ottenstein-Programme, Faculty of Medicine, University of Freiburg (Germany); Rössle, Martin, E-mail: Martin-Roessle@t-online.de [University Hospital, Department of Gastroenterology, Hugstetterstrasse 55, 79106 Freiburg (Germany); Praxiszentrum für Gastroenterologie, Bertoldstrasse 48, 79098 Freiburg (Germany)

    2017-04-15

    Purpose: This study investigates the behaviour of self-expanding nitinol stents at the time of TIPS-implantation and thereafter. Methods: Hundred consecutive patients with cirrhosis receiving a TIPS revision were included. The smallest stent diameter was measured radiologically immediately after implantation and before shunt revision. Accuracy of the measurement was assessed by comparing the nominal stent diameter with the largest stent diameter measured at the time of revision. Results: Pearson correlation between largest measured and nominal diameters was excellent (r = 0.952, p < 0.001) showing that measurements are accurate. At TIPS implantation all stents were markedly underdilated reaching only 76–92% of their nominal diameter. Smallest measured diameters were similar (8 mm) irrespective of the nominal diameter (8, 9, 10 mm) of the stent. In addition, smallest diameters of 10 mm stents were similar irrespective whether 8, 9 or 10 mm balloons were used. During a mean follow-up of 12.7 ± 17.8 months (median 3 months, range 1–81) stents expanded by 0.5–1.6 mm dependent on the nominal stent size (8, 9, 10 mm) and the grade of primary underdilation. No significant difference was found between Viatorr and bare stents. Conclusions: At TIPS-implantation, the compliance of the surrounding tissue predominantly determines the stent diameter. The nominal size of the stent or the dilatation balloon has little influence. Accurate adjustment of a desired pressure gradient is, therefore, not possible. During follow-up, stents expand towards their nominal diameter questioning the usefulness of underdilation.

  17. The underdilation of nitinol stents at TIPS implantation: Solution or illusion?

    International Nuclear Information System (INIS)

    Mollaiyan, Ashkan; Bettinger, Dominik; Rössle, Martin

    2017-01-01

    Purpose: This study investigates the behaviour of self-expanding nitinol stents at the time of TIPS-implantation and thereafter. Methods: Hundred consecutive patients with cirrhosis receiving a TIPS revision were included. The smallest stent diameter was measured radiologically immediately after implantation and before shunt revision. Accuracy of the measurement was assessed by comparing the nominal stent diameter with the largest stent diameter measured at the time of revision. Results: Pearson correlation between largest measured and nominal diameters was excellent (r = 0.952, p < 0.001) showing that measurements are accurate. At TIPS implantation all stents were markedly underdilated reaching only 76–92% of their nominal diameter. Smallest measured diameters were similar (8 mm) irrespective of the nominal diameter (8, 9, 10 mm) of the stent. In addition, smallest diameters of 10 mm stents were similar irrespective whether 8, 9 or 10 mm balloons were used. During a mean follow-up of 12.7 ± 17.8 months (median 3 months, range 1–81) stents expanded by 0.5–1.6 mm dependent on the nominal stent size (8, 9, 10 mm) and the grade of primary underdilation. No significant difference was found between Viatorr and bare stents. Conclusions: At TIPS-implantation, the compliance of the surrounding tissue predominantly determines the stent diameter. The nominal size of the stent or the dilatation balloon has little influence. Accurate adjustment of a desired pressure gradient is, therefore, not possible. During follow-up, stents expand towards their nominal diameter questioning the usefulness of underdilation.

  18. Extensive caustic esophageal stricture in children can be treated by serial dilatations interspersed with silicone-covered nitinol stenting

    Directory of Open Access Journals (Sweden)

    Veronica Alonso

    2016-01-01

    Full Text Available Recurrent esophageal stenosis secondary to caustic ingestion may be challenging to treat. Self-expandable esophageal stents may be an alternative to repetitive endoscopic esophageal dilatation. We report a case of a 2-year-old male child with an extensive esophageal caustic stricture successfully treated using a combination of endoscopic dilatation and stenting. After 5 months of serial balloon dilatations, three nitinol internal silicone covered self-expandable stents were placed through the patient′s gastrostomy spanning the entire esophagus. The stents were positioned using a combination of both endoscopic and fluoroscopic guidance. The procedure was repeated with only one stent 3 months later. A new stricture in the proximal esophagus needed surgical resection and anastomosis, followed by two pneumatic dilatations with progressively longer asymptomatic intervals. The results are promising with the patient able to use his own esophagus; however, this is a single case and optimal stent standing time is still to be determined.

  19. Treatment of a Ruptured Anastomotic Esophageal Stricture Following Bougienage with a Dacron-Covered Nitinol Stent

    International Nuclear Information System (INIS)

    Heindel, Walter; Gossmann, Axel; Fischbach, Roman; Michel, Olaf; Lackner, Klaus

    1996-01-01

    A patient suffering from esophagorespiratory fistula after bougienage of a benign stricture at the site of the anastomosis between a jejunal interposition and the esophagus was referred for interventional treatment. A prototype nitinol stent centrally covered with Dacron was implanted under regional anesthesia and fluoroscopic guidance. The self-expanding prosthesis dilated the stenosis completely and closed the fistula, with consequent improvement in respiratory and nutritional status and thus the general quality of life. The patient was able to eat and drink normally until death 3 months later due to progression of his underlying malignant disease

  20. Successful Exclusion of a Large Femoropopliteal Aneurysm with a Covered Nitinol Stent

    International Nuclear Information System (INIS)

    Dorffner, Roland; Winkelbauer, Friedrich; Kettenbach, Joachim; Staudacher, Michael; Lammer, Johannes

    1996-01-01

    A 70-year-old woman presented with a large femoropopliteal aneurysm. A covered nitinol stent was implanted successfully and complete exclusion of the aneurysm was achieved. At follow-up 5 months later the stent was still patent and the patient was free of symptoms. However, moderate stenosis was seen at the proximal end of the stent

  1. Nitinol stents in the treatment of benign proximal tracheal stenosis or tracheomalacia.

    Science.gov (United States)

    Isa, A Y; Macandie, C; Irvine, B W

    2006-01-01

    Nitinol stents have been used in the treatment of benign tracheal stenosis. A retrospective review of five patients treated at Stobhill Hospital over the last six and a half years is presented. Age at presentation ranged from 17 to 76 years. The minimum follow-up period was 23 months and the maximum was 78 months. All our patients were successfully decannulated, with none requiring recannulation. Four patients developed granulation tissue related to the stent at intervals ranging from three weeks to 41 months post stenting. Topical mitomycin C application has been useful after resection of granulations using the carbon dioxide (CO2) laser. Stent migration occurred in one patient three weeks after insertion. Nitinol stents are easy to insert and effective in the treatment of tracheal stenosis, but can have associated morbidity. Their use should be considered carefully, as insertion should be regarded as permanent. Publications reporting experience and outcome with the use of Nitinol stents in the trachea are reviewed.

  2. Endovascular Treatment of a Giant Superior Mesenteric Artery Pseudoaneurysm Using a Nitinol Stent-Graft

    International Nuclear Information System (INIS)

    Gandini, Roberto; Pipitone, Vincenzo; Konda, Daniel; Pendenza, Gianluca; Spinelli, Alessio; Stefanini, Matteo; Simonetti, Giovanni

    2005-01-01

    A 68-year-old woman presenting with gastrointestinal bleeding (hematocrit 19.3%) and in a critical clinical condition (American Society of Anesthesiologists grade 4) from a giant superior mesenteric artery pseudoaneurysm (196.0 x 131.4 mm) underwent emergency endovascular treatment. The arterial tear supplying the pseudoaneurysm was excluded using a 5.0 mm diameter and 31 mm long monorail expanded polytetrafluoroethylene (ePTFE)-covered self-expanding nitinol stent. Within 6 days of the procedure, a gradual increase in hemoglobin levels and a prompt improvement in the clinical condition were observed. Multislice CT angiograms performed immediately, 5 days, 30 days and 3 months after the procedure confirmed the complete exclusion of the pseudoaneurysm

  3. Nitinol Stents in the Femoropopliteal Artery: A Mechanical Perspective on Material, Design, and Performance.

    Science.gov (United States)

    Maleckis, Kaspars; Anttila, Eric; Aylward, Paul; Poulson, William; Desyatova, Anastasia; MacTaggart, Jason; Kamenskiy, Alexey

    2018-05-01

    Endovascular stenting has matured into a commonly used treatment for peripheral arterial disease (PAD) due to its minimally invasive nature and associated reductions in short-term morbidity and mortality. The mechanical properties of the superelastic Nitinol alloy have played a major role in the explosion of peripheral artery stenting, with modern stents demonstrating reasonable resilience and durability. Yet in the superficial femoral and popliteal arteries, even the newest generation Nitinol stents continue to demonstrate clinical outcomes that leave significant room for improvement. Restenosis and progression of native arterial disease often lead to recurrence of symptoms and reinterventions that increase morbidity and health care expenditures. One of the main factors thought to be associated with stent failure in the femoropopliteal artery (FPA) is the unique and highly dynamic mechanical environment of the lower limb. Clinical and experimental data demonstrate that the FPA undergoes significant deformations with limb flexion. It is hypothesized that the inability of many existing stent designs to conform to these deformations likely plays a role in reconstruction failure, as repetitive movements of the leg and thigh combine with mechanical mismatch between the artery and the stent and result in mechanical damage to both the artery and the stent. In this review we will identify challenges and provide a mechanical perspective of FPA stenting, and then discuss current research directions with promise to provide a better understanding of Nitinol, specific features of stent design, and improved characterization of the biomechanical environment of the FPA to facilitate development of better stents for patients with PAD.

  4. Endoscopic management of unresectable malignant gastroduodenal obstruction with a nitinol uncovered metal stent: A prospective Japanese multicenter study

    Science.gov (United States)

    Sasaki, Reina; Sakai, Yuji; Tsuyuguchi, Toshio; Nishikawa, Takao; Fujimoto, Tatsuya; Mikami, Shigeru; Sugiyama, Harutoshi; Yokosuka, Osamu

    2016-01-01

    AIM: To determine the safety and efficacy of endoscopic duodenal stent placement in patients with malignant gastric outlet obstruction. METHODS: This prospective, observational, multicenter study included 39 consecutive patients with malignant gastric outlet obstruction. All patients underwent endoscopic placement of a nitinol, uncovered, self-expandable metal stent. The primary outcome was clinical success at 2 wk after stent placement that was defined as improvement in the Gastric Outlet Obstruction Scoring System score relative to the baseline. RESULTS: Technical success was achieved in all duodenal stent procedures. Procedure-related complications occurred in 4 patients (10.3%) in the form of mild pneumonitis. No other morbidities or mortalities were observed. The clinical success rate was 92.3%. The mean survival period after stent placement was 103 d. The mean period of stent patency was 149 d and the patency remained acceptable for the survival period. Stent dysfunction occurred in 3 patients (7.7%) on account of tumor growth. CONCLUSION: Endoscopic management using duodenal stents for patients with incurable malignant gastric outlet obstruction is safe and improved patients’ quality of life. PMID:27076769

  5. Use of retrievable self-expanding stent in treating childhood benign oesophageal stricture

    International Nuclear Information System (INIS)

    Yu Juming; Fan Guoping; Zhong Weixing; Zhu Ming

    2007-01-01

    Objective: To evaluate the methods and effect of retrievable self-expanding esophageal stent in treating benign esophageal stenosis of children. Methods: The covered retrievable expandable nitinol stents were placed in 10 children with corrosive esophageal stenosis and post-anastomotic stenosis, age ranged from 2 to 12 years, the dysphagia scores were 3, Barium esophagography was taken before the use of retrievable stent. Results: The stents were placed safely in all patients without complications and were successfully removed after all. After the stent placement, all patients could take solid food without dysphagia. During 6 to 12 months follow-up after the stent removal, all children could eat satisfactorily with the dysphagia score as 0. Conclusion: The use of covered retrievable expandable stent is effective and safe in treating childhood benign esophageal stenosis. (authors)

  6. Superficial femoral artery TASC D Registry: twelve-month effectiveness analysis of the Pulsar-18 SE nitinol stent in patients with critical limb ischemia.

    Science.gov (United States)

    Lichtenberg, M; Stahlhoff, W; Boese, D

    2013-08-01

    Single center observational study analyzing the primary patency rate and freedom from target lesions revascularization rate of the Pulsar-18 nitinol stent after recanalization of long superficial femoral artery (SFA) occlusions (TASC D) in 22 patients with critical limb ischemia (CLI). Between 1/2011 and 7/2011, 22 consecutive patients (9 male, 13 female) with chronic total occlusions (CTO) of the femoro-popliteal arteries presenting with CLI (17 patients with Rutherford 4 score, and 5 patients with Rutherford 5 score) were enrolled and successfully recanalized using the Pulsar-18 self-expanding (SE) nitinol stent (BIOTRONIK AG, Buelach, Switzerland). Primary patency at 12 months was defined as no binary restenosis (>50%) on Duplex ultrasound (PSVRPulsar-18 SE nitinol stent was 77% with a per protocol restenosis in 5 of 22 patients. Seventeen patients showed a walking capacity on treadmill test >300 meters (Rutherford II). Two patients with a documented restenosis were Rutherford, these patients were treated conservatively. Three patients with restenosis and a Rutherford III score were scheduled for an endovascular target lesion revascularization leading to a freedom from target lesion revascularization rate of 86%. Endovascular intervention of long SFA occlusions using subintimal or intraluminal recanalization technique with implantation of the Pulsar-18 SE nitinol stent in CLI patients is safe and clinically effective with a primary patency rate after 12 months of 77% and a freedom from target lesion revascularization rate of 86%.

  7. Nitinol Stents in the Femoropopliteal Artery: A Mechanical Perspective on Material, Design, and Performance

    Science.gov (United States)

    Maleckis, Kaspars; Anttila, Eric; Aylward, Paul; Poulson, William; Desyatova, Anastasia; MacTaggart, Jason; Kamenskiy, Alexey

    2018-01-01

    Endovascular stenting has matured into a commonly used treatment for peripheral arterial disease (PAD) due to its minimally invasive nature and associated reductions in short-termmorbidity and mortality. The mechanical properties of the superelastic Nitinol alloy have played a major role in the explosion of peripheral artery stenting, with modern stents demonstrating reasonable resilience and durability. Yet in the superficial femoral and popliteal arteries, even the newest generation Nitinol stents continue to demonstrate clinical outcomes that leave significant room for improvement. Restenosis and progression of native arterial disease often lead to recurrence of symptoms and reinterventions that increase morbidity and health care expenditures. One of the main factors thought to be associated with stent failure in the femoropopliteal artery (FPA) is the unique and highly dynamic mechanical environment of the lower limb. Clinical and experimental data demonstrate that the FPA undergoes significant deformations with limb flexion. It is hypothesized that the inability of many existing stent designs to conform to these deformations likely plays a role in reconstruction failure, as repetitive movements of the leg and thigh combine with mechanical mismatch between the artery and the stent and result in mechanical damage to both the artery and the stent. In this review we will identify challenges and provide a mechanical perspective of FPA stenting, and then discuss current research directions with promise to provide a better understanding of Nitinol, specific features of stent design, and improved characterization of the biomechanical environment of the FPA to facilitate development of better stents for patients with PAD. PMID:29470746

  8. Statistical characteristics of surface integrity by fiber laser cutting of Nitinol vascular stents

    International Nuclear Information System (INIS)

    Fu, C.H.; Liu, J.F.; Guo, Andrew

    2015-01-01

    Graphical abstract: - Highlights: • Precision kerf with tight tolerance of Nitinol stents can be cut by fiber laser. • No HAZ in the subsurface was detected due to large grain size. • Recast layer has lower hardness than the bulk. • Laser cutting speed has a higher influence on surface integrity than laser power. - Abstract: Nitinol alloys have been widely used in manufacturing of vascular stents due to the outstanding properties such as superelasticity, shape memory, and superior biocompatibility. Laser cutting is the dominant process for manufacturing Nitinol stents. Conventional laser cutting usually produces unsatisfactory surface integrity which has a significant detrimental impact on stent performance. Emerging as a competitive process, fiber laser with high beam quality is expected to produce much less thermal damage such as striation, dross, heat affected zone (HAZ), and recast layer. To understand the process capability of fiber laser cutting of Nitinol alloy, a design-of-experiment based laser cutting experiment was performed. The kerf geometry, roughness, topography, microstructure, and hardness were studied to better understand the nature of the HAZ and recast layer in fiber laser cutting. Moreover, effect size analysis was conducted to investigate the relationship between surface integrity and process parameters.

  9. Statistical characteristics of surface integrity by fiber laser cutting of Nitinol vascular stents

    Energy Technology Data Exchange (ETDEWEB)

    Fu, C.H., E-mail: cfu5@crimson.ua.edu [Dept of Mechanical Engineering, The University of Alabama, Tuscaloosa, AL 35487 (United States); Liu, J.F. [Dept of Mechanical Engineering, The University of Alabama, Tuscaloosa, AL 35487 (United States); Guo, Andrew [Dept of Mechanical Engineering, The University of Alabama, Tuscaloosa, AL 35487 (United States); College of Arts and Science, Vanderbilt University, Nashville, TN 37235 (United States)

    2015-10-30

    Graphical abstract: - Highlights: • Precision kerf with tight tolerance of Nitinol stents can be cut by fiber laser. • No HAZ in the subsurface was detected due to large grain size. • Recast layer has lower hardness than the bulk. • Laser cutting speed has a higher influence on surface integrity than laser power. - Abstract: Nitinol alloys have been widely used in manufacturing of vascular stents due to the outstanding properties such as superelasticity, shape memory, and superior biocompatibility. Laser cutting is the dominant process for manufacturing Nitinol stents. Conventional laser cutting usually produces unsatisfactory surface integrity which has a significant detrimental impact on stent performance. Emerging as a competitive process, fiber laser with high beam quality is expected to produce much less thermal damage such as striation, dross, heat affected zone (HAZ), and recast layer. To understand the process capability of fiber laser cutting of Nitinol alloy, a design-of-experiment based laser cutting experiment was performed. The kerf geometry, roughness, topography, microstructure, and hardness were studied to better understand the nature of the HAZ and recast layer in fiber laser cutting. Moreover, effect size analysis was conducted to investigate the relationship between surface integrity and process parameters.

  10. Biomedical engineering in design and application of nitinol stents with shape memory effect

    Science.gov (United States)

    Ryklina, E. P.; Khmelevskaya, I. Y.; Morozova, Tamara V.; Prokoshkin, S. D.

    1996-04-01

    Our studies in the field of endosurgery in collaboration with the physicians of the National Research Center of Surgery of the Academy of Medical Sciences are carried out beginning in 1983. These studies laid the foundation for the new direction of X-ray surgery--X-ray Nitinol stenting of vessels and tubular structures. X-ray nitinol stents are unique self-fixing shells based on the shape memory effect and superelasticity of nickel-titanium alloys self- reconstructed under human body temperature. Applied for stenting of arteries in cases of stenosis etc., bile ducts in cases of benign and malignant stenoses, digestive tract in cases of oesophageal cancer and cervical canal uterus in cases of postsurgical atresiss and strictures of uterine. The purpose of stenting is restoration of the shape of artery or tubular structure by a cylinder frame formation. The especially elaborated original method of stenting allows to avoid the traditional surgical operation, i.e. the stenting is performed without blood, narcosis and surgical knife. The stent to be implanted is transported into the affected zone through the puncture under the X-ray control. Clinical applications of X-ray endovascular stenting has been started in March 1984. During this period nearly 400 operations on stenting have been performed on femoral, iliac, brachio-cephalic, subclavian arteries, bile ducts, tracheas, digestive tract and cervical canal uterus.

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

    Science.gov (United States)

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

    2017-09-01

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

  12. High-resolution 3D X-ray imaging of intracranial nitinol stents

    International Nuclear Information System (INIS)

    Snoeren, Rudolph M.; With, Peter H.N. de; Soederman, Michael; Kroon, Johannes N.; Roijers, Ruben B.; Babic, Drazenko

    2012-01-01

    To assess an optimized 3D imaging protocol for intracranial nitinol stents in 3D C-arm flat detector imaging. For this purpose, an image quality simulation and an in vitro study was carried out. Nitinol stents of various brands were placed inside an anthropomorphic head phantom, using iodine contrast. Experiments with objects were preceded by image quality and dose simulations. We varied X-ray imaging parameters in a commercially interventional X-ray system to set 3D image quality in the contrast-noise-sharpness space. Beam quality was varied to evaluate contrast of the stents while keeping absorbed dose below recommended values. Two detector formats were used, paired with an appropriate pixel size and X-ray focus size. Zoomed reconstructions were carried out and snapshot images acquired. High contrast spatial resolution was assessed with a CT phantom. We found an optimal protocol for imaging intracranial nitinol stents. Contrast resolution was optimized for nickel-titanium-containing stents. A high spatial resolution larger than 2.1 lp/mm allows struts to be visualized. We obtained images of stents of various brands and a representative set of images is shown. Independent of the make, struts can be imaged with virtually continuous strokes. Measured absorbed doses are shown to be lower than 50 mGy Computed Tomography Dose Index (CTDI). By balancing the modulation transfer of the imaging components and tuning the high-contrast imaging capabilities, we have shown that thin nitinol stent wires can be reconstructed with high contrast-to-noise ratio and good detail, while keeping radiation doses within recommended values. Experimental results compare well with imaging simulations. (orig.)

  13. Endotracheal expandable metallic stent placement in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, S; Tanabe, Y; Fujiwara, Y; Koyama, T; Tanigawa, N; Kobayashi, M; Katsube, Y; Nakamura, H [Tottori Univ. School of Medicine, Yonago (Japan). Dept. of Radiology Research Inst. for Microbial Diseases, Osaka (Japan). Dept. of Radiology

    1991-01-01

    Various types of Gianturco zig-zag wire stent were implanted into the tracheas of 4 dogs to define the suitable characteristics of the endotracheal wire stent in these animals. These stents were constructed of 0.45, and 0.33 mm stainless steel wire. The diameter of the fully expanded stents was 3 cm and their lengths were 2, 3, and 4 cm. The 2 cm stent constructed of 0.33 mm wire showed minimum pathologic changes of the trachea of the dog compared to the other stents, and at the same time had a complete covering of ciliated columnar epithelium over the stent surface. (orig.).

  14. Usefulness of a balloon-expandable, covered stent for the transjugular intrahepatic portosystemic shunt

    Directory of Open Access Journals (Sweden)

    Rössle M

    2018-01-01

    Full Text Available The availability of polytetrafluoroethylene (PTFE covered, self-expandable nitinol stents in 2001 considerably improved the patency, response rates and survival of the transjugular intrahepatic portosystemic shunt (TIPS. Side effects of portosystemic shunting such as hepatic encephalopathy (HE and worsening of hepatic function, however, remained a problem. To reduce HE, underdilatation of nitinol stents has been practiced for many years. However, as shown recently, underdilatation was a flop since, due to their intrinsic memory, nitinol stents always expanded to reach their nominal diameter of 8 or 10 mm. To overcome this problem and to be able to perform permanent shunts with a smaller diameter of < 8 mm, we studied the usefulness of a balloon-expandable, covered, metallic stent which allowed adjustment to any diameter between 5 and 12 mm. Methods: 30 patients with cirrhosis and symptomatic portal hypertension were included. The mean Child-Pugh score was 8 ± 2.17 patients had refractory ascites, 9 patients variceal bleeding and four patients other indications for the TIPS. Results: The TIPS was successfully implanted in all patients within 69.6 ± 21.8 min. The shunt reduced the portosystemic pressure gradient by 57.5 ± 14.2% with a mean stent diameter of 7.4 ± 1.0 mm (5 -10.3 mm. During a mean follow-up of 330 ± 249 days, shunt revision was necessary in 5 patients (17%, four of them had insufficient response and received stent dilatation and one patient had stent misplacement requiring a parallel shunt. Three patients (10% developed HE. Conclusions: The covered, balloon-expandable stent could be placed accurately and allowed creation of adapted shunts with smaller diameters as usual. This resulted in a comparatively low rate of HE.

  15. Percutaneous therapy of inoperable biliary stenoses and occlusions with a new self-expanding nitinol stent (SMART); Perkutane Therapie inoperabler maligner Stenosen und Verschluesse der Gallenwege mit einem neu entwickelten selbstexpandierbaren Nitinolstent (SMART)

    Energy Technology Data Exchange (ETDEWEB)

    Zorger, N.; Lenhart, M.; Strotzer, M.; Paetzel, C.; Hamer, O.; Feuerbach, S.; Link, J. [Regensburg Univ. (Germany). Inst. fuer Roentgendiagnostik

    2002-10-01

    Objective: To evaluate the treatment of malignant biliary stenoses and occlusions using a new stent. Methods: In a prospective study, 25 patients with malignant obstructive jaundice were treated with SMART stents. The handling and the quality of stent expansion were documented. Stent function was assessed 2-4 days after intervention by cholangiography and laboratory tests. A follow-up was performed three months, after stent placement. Results: All lesions were treated successfully, with a total of 35 stents implanted. In 14 patients a further balloon dilatation was performed after stent placement (8-10 mm diameter/40-80 mm length). The mean serum bilirubin level decreased significantly from 11.6 mg/dl to 4.6 mg/dl after intervention (p<0.05). The follow-up showed a mean serum bilirubin level at 4.0 mg/dl. In 4 cases (16%) a further intervention (PTCD or stent) was performed. Six patients died due to tumor progression. The stents proved to be patent in 79% (n=15) of patients alive at the time of follow-up. Conclusions: Placement of the SMART stent for the therapy of malignant biliary lesions yields good technical and clinical results. (orig.) [German] Zielsetzung: Evaluation der technischen Handhabung und Effizienz eines neu entwickelten Stents zur Therapie maligner Gallenwegsstenosen und Verschluesse. Material und Methodik: In einer prospektiven Studie wurden 25 Patienten mit Verschlussikterus bei maligner Gallengangsstenose palliativ mit dem SMART {sup trademark} -Stent behandelt. Evaluiert wurden die Handhabung des Stents und die Qualitaet der Stententfaltung. Die Stentfunktion wurde nach 2-4 Tagen ueber eine liegende interne/externe Drainage cholangiographisch sowie anhand des Verlaufs der Laborparameter kontrolliert. Eine zusaetzliche Kontrolle der Stentfunktion erfolgte nach drei Monaten. Dabei wurden das subjektive Wohlbefinden des Patienten, der aktuelle Gesamtbilirubinspiegel im Serum und die Anzahl weiterer, im Nachsorgezeitraum durchgefuehrter

  16. Polyorethaoe-covered nitinol strecker stents as primary palliative treatment of malignant biliary obstruction

    International Nuclear Information System (INIS)

    Kanasaki, Shuzo; Furukawa, Akira; Kane, Teruyuki; Murata, Kiyoshi

    2000-01-01

    Purpose: To evaluate the clinical efficacy of the polyure-thane-covered Nitinol Strecker stent in the treatment of patients with malignant biliary obstruction.Methods: Twenty-three covered stents produced by us were placed in 18 patients with malignant biliary obstruction. Jaundice was caused by cholangiocarcinoma (n=5), pancreatic Cancer (n=6), gallbladder Cancer (n=4), metastatic lymph nodes (n=2), and tumor of the papilla (n=1).Resulrs: The mean patency period of the Stents was 37.5 weeks (5-106 weeks). Recurrent obstructive jaundice occurred in two patients (11%). Adequate biliary drainage over 50 weeks or until death was achieved in 17 of 18 patients (94.4%). Late cholangitis was observed in two patients whose stents bridged the ampulla of Vater. Other late severe complications were not encountered.Conclusion: Although more study is necessary, our results suggest the clinical efficacy of our covered Nitinol Strecker stent in the management of obstructive jaundice caused by malignant diseases.

  17. Mechanical stability of the diamond-like carbon film on nitinol vascular stents under cyclic loading

    International Nuclear Information System (INIS)

    Kim, Hyun-Jong; Moon, Myoung-Woon; Lee, Kwang-Ryeol; Seok, Hyun-Kwang; Han, Seung-Hee; Ryu, Jae-Woo; Shin, Kyong-Min; Oh, Kyu Hwan

    2008-01-01

    The mechanical stability of diamond-like carbon (DLC) films coated on nitinol vascular stents was investigated under cyclic loading condition by employing a stent crimping system. DLC films were coated on the vascular stent of a three dimensional structure by using a hybrid ion beam system with rotating jig. The cracking or delamination of the DLC coating occurred dominantly near the hinge connecting the V-shaped segments of the stent where the maximum strain was induced by a cyclic loading of contraction and extension. However the failures were significantly suppressed as the amorphous Si (a-Si) buffer layer thickness increased. Interfacial adhesion strength was estimated from the spalled crack size in the DLC coating for various values of the a-Si buffer layer thickness

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

    Science.gov (United States)

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

    2016-03-01

    The objective of this study was to assess tracheal reactivity after the deployment of different self-expandable metal stents (SEMS). Forty female New Zealand rabbits were divided into four groups. Three groups received three different SEMS: steel (ST), nitinol (NiTi), or nitinol drug-eluting stent (DES); the fourth group was the control group (no stent). Stents were deployed percutaneously under fluoroscopic guidance. Animals were assessed by multi-slice, computed tomography (CT) scans, and tracheas were collected for anatomical pathology (AP) study. Data from CT and AP were statistically analyzed and correlated. The DES group had the longest stenosis (20.51±14.08mm vs. 5.84±12.43 and 6.57±6.54mm in NiTi and ST, respectively, day 30; Pstent. CT was more effective in detecting wall thickening (positive correlation of 68.9%; Pstent, while DES caused significant lesions that may be related to drug dosage. This type of DES stent is therefore not recommended for the treatment of tracheobronchial stenosis. Copyright © 2015 SEPAR. Published by Elsevier Espana. All rights reserved.

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

    Science.gov (United States)

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

    2017-07-01

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

  20. Oversizing and Restenosis with Self-Expanding Stents in Iliofemoral Arteries

    International Nuclear Information System (INIS)

    Saguner, Ardan M.; Traupe, Tobias; Räber, Lorenz; Hess, Nina; Banz, Yara; Saguner, Arhan R.; Diehm, Nicolas; Hess, Otto M.

    2012-01-01

    Purpose: Uncoated self-expanding nitinol stents (NS) are commonly oversized in peripheral arteries. In current practice, 1-mm oversizing is recommended. Yet, oversizing of NS may be associated with increased restenosis. To provide further evidence, NS were implanted in porcine iliofemoral arteries with a stent-to-artery-ratio between 1.0 and 2.3. Besides conventional uncoated NS, a novel self-expanding NS with an antiproliferative titanium-nitride-oxide (TiNOX) coating was tested for safety and efficacy. Methods: Ten uncoated NS and six TiNOX-coated NS (5–6 mm) were implanted randomly in the iliofemoral artery of six mini-pigs. After implantation, quantitative angiography (QA) was performed for calculation of artery and minimal luminal diameter. Follow-up was performed by QA and histomorphometry after 5 months. Results: Stent migration, stent fracture, or thrombus formation were not observed. All stents were patent at follow-up. Based on the location of the stent (iliac/femoral) and the stent-to-artery-ratio, stent segments were divided into “normal-sized” (stent-to-artery-ratio < 1.4, n = 12) and “oversized” (stent-to-artery-ratio ≥ 1.4, n = 9). All stent segments expanded to their near nominal diameter during follow-up. Normal-sized stent segments increased their diameter by 6% and oversized segments by 29%. A significant correlation between oversizing and restenosis by both angiography and histomorphometry was observed. Restenosis rates were similar for uncoated NS and TiNOX-coated NS. Conclusions: TiNOX-coated NS are as safe and effective as uncoated NS in the porcine iliofemoral artery. All stents further expand to near their nominal diameter during follow-up. Oversizing is linearly and positively correlated with neointimal proliferation and restenosis, which may not be reduced by TiNOX-coating.

  1. Use of Nitinol Stents Following Recanalization of Central Venous Occlusions in Hemodialysis Patients

    International Nuclear Information System (INIS)

    Rajan, Dheeraj K.; Saluja, Jasdeep S.

    2007-01-01

    Purpose. To retrospectively review the patency of endovascular interventions with nitinol stent placement for symptomatic central venous occlusions in hemodialysis patients. Methods. A retrospective review of all patients who underwent endovascular interventions for dysfunctional hemodialysis grafts and fistulas was performed from April 2004 to August 2006. A total of 6 patients presented with arm and/or neck and facial swelling and left brachiocephalic vein occlusion. The study group consisted of 3 men and 3 women with a mean age of 79.5 years (SD 11.2 years). Of these 6 patients, 1 had a graft and 5 had fistulas in the left arm. The primary indication for nitinol stent placement was technical failure of angioplasty following successful traversal of occluded central venous segments. Patency was assessed from repeat fistulograms and central venograms performed when patients redeveloped symptoms or were referred for access dysfunction determined by the ultrasound dilution technique. No patients were lost to follow-up. Results. Nitinol stent placement to obtain technically successful recanalization of occluded venous segments was initially successful in 5 of 6 patients (83%). In 1 patient, incorrect stent positioning resulted in partial migration to the superior vena cava requiring restenting to prevent further migration. Clinical success was observed in all patients (100%). Over the follow-up period, 2 patients underwent repeat intervention with angioplasty alone. Primary patency was 83.3% (95% CI 0.5-1.2) at 3 months, and 66.7% at 6 and 12 months (0.2-1.1, 0.1-1.2). Secondary patency was 100% at 12 months with 3 patients censored over that time period. Mean primary patency was 10.4 months with a mean follow-up of 12.4 months. No complications related to recanalization of the occluded central venous segments were observed. Conclusion. Our initial experience has demonstrated that use of nitinol stents for central venous occlusion in hemodialysis patients is

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

    Science.gov (United States)

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

    2017-10-01

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

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

    Science.gov (United States)

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

    2014-04-15

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

  4. Assessment of a Polyester-Covered Nitinol Stent in the Canine Aorta and Iliac Arteries

    International Nuclear Information System (INIS)

    Castaneda, Flavio; Ball-Kell, Susan M.; Young, Kate; Li Ruizong

    2000-01-01

    Purpose: To evaluate the patency and healing characteristics of a woven polyester fabric-covered stent in the canine model.Methods: Twenty-four self-expanding covered stents were placed in the infrarenal aorta and bilateral common iliac arteries of eight dogs and evaluated at 1 (n = 2), 3 (n = 2), and 6 (n = 4) months. Stent assessment was done using angiography prior to euthanasia, and light and scanning electron microscopy.Results: Angiographically, just prior to euthanasia, 8 of 8 aortic and 14 of 16 iliac endovascular covered stents were patent. Histologically, the stented regions showed complete endothelialization 6 months after graft implantation. A neointima had formed inside the stented vessel regions resulting in complete encasement of the fabric-covered stent by 3 months after graft implantation. Medial compression with smooth muscle cell atrophy was present in all stented regions. Explanted stent wires, examined by scanning electron microscopy, showed pitting but no cracks or breakage.Conclusion: The covered stent demonstrated predictable healing and is effective in preventing stenosis in vessels 10.0 mm or greater in diameter but does not completely preclude stenosis in vessels 6.0 mm or less in diameter

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

    Science.gov (United States)

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

    2002-10-01

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

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

    Science.gov (United States)

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

    2015-02-01

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

  7. Complication after self expandable metallic stent for esophageal cancer

    International Nuclear Information System (INIS)

    Nagahama, Takeshi; Maruyama, Michio; Kato, Kiyomi; Shinoura, Hiroshi; Hasegawa, Kumi; Takashima, Itaru; Ebuchi, Masakazu

    2003-01-01

    Major complications after placement of esophageal stent and airway stent were reviewed and evaluated. Four patients, including two patients with perforations and two patients with fistula formation, developed major complications after placement of a self expandable metallic stent. Two patients underwent additional radiation to improve stricture after stent placement. In one patient, stent placement was selected to improve esophageal stricture that occurred after radical radiation therapy. In one patient, migration of stent into the lesion caused a perforation. It can be concluded that additional radiation after stent placement increases the risk of complication. Stent migration also can lead to the risk of perforation. (author)

  8. The EPIC nitinol stent system in the treatment of iliac artery lesions: one-year results from the ORION clinical trial.

    Science.gov (United States)

    Clair, Daniel G; Adams, Julie; Reen, Bernard; Feldman, Robert; Starr, Jean; Diaz-Cartelle, Juan; Dawkins, Keith D

    2014-04-01

    To report the 1-year results of a pivotal study for a new-generation nitinol stent for the treatment of iliac atherosclerotic lesions. The ORION trial (ClinicalTrials.gov identifier NCT00896337) was a single-arm, non-randomized, prospective, multicenter clinical trial that enrolled 125 patients (81 men; mean age 61.1±9.3 years) implanted with the EPIC self-expanding nitinol stent system in 166 de novo or restenotic iliac artery lesions ≤13 cm long. The primary endpoint was the 9-month major adverse event rate [i.e., device- or procedure-related death within 30 days, myocardial infarction during the index hospitalization, target vessel revascularization (TVR), or index limb amputation]. Follow-up occurred at hospital discharge and at 1, 9, and 12 months. An independent core laboratory evaluated ultrasound results at 1, 9, and 12 months. The primary endpoint met the prespecified performance goal, with only 3.4% (4/117) of patients experiencing a major adverse event by 9 months (p<0.0001). By 12 months, 6 (5.4%) of 111 patients had TVR; none had an index limb amputation. The ankle-brachial index, Walking Impairment Questionnaire, and Rutherford classifications all showed sustained improvements through 12 months. Primary patency was 94.4% with comparable results for lesions classified as complex (TASC II C/D 95.5%) or non-complex (TASC II A/B 95.0%). The EPIC stent system demonstrated safety and effectiveness through 12 months, including improvements for complex lesions. The EPIC stent is a viable alternative to surgery for patients with either complex or non-complex lesions.

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

    Science.gov (United States)

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

    2012-12-01

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

  10. Functional Self-Expandable Metal Stents in Biliary Obstruction

    Science.gov (United States)

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

    2013-01-01

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

  11. Factors leading to tracheobronchial self-expandable metallic stent fracture.

    Science.gov (United States)

    Chung, Fu-Tsai; Lin, Shu-Min; Chen, Hao-Cheng; Chou, Chun-Liang; Yu, Chih-Teng; Liu, Chien-Ying; Wang, Chun-Hua; Lin, Horng-Chyuan; Huang, Chien-Da; Kuo, Han-Pin

    2008-11-01

    This retrospective study was to determine factors that contribute to self-expandable metallic stent fracture in patients with tracheobronchial disease. From 2001 to 2006, 139 patients (age, 62.1 +/- 15.4 years; range, 23-87 years) with benign (n = 62) and malignant (n = 77) tracheobronchial disease received 192 Ultraflex (Boston Scientific, Natick, Mass) self-expandable metallic stents (98 in patients with benign disease and 94 in patients with malignant disease). Seventeen fractured self-expandable metallic stents were found; the incidence was 12.2% (17/139 patients) among patients with tracheobronchial disease. Tortuous airway (odds ratio, 4.06; 95% confidence interval, 1.04-18.34; P = .04) independently predicted self-expandable metallic stent fracture. Most self-expandable metallic stent fractures (64.7%, 11/17) were detected 500 to 1000 days after self-expandable metallic stent implantation. Clinical presentations for patients with fractured self-expandable metallic stents included dyspnea exacerbation (70.6%, 12/17) and cough (23.5%, 4/17). Self-expandable metallic stent fracture is not uncommon in patients with tracheobronchial disease. Tortuous airway is an independent predictor for it. Although management of the fractured self-expandable metallic stent in our study was feasible and safe, self-expandable metallic stents should be restricted to a more select population.

  12. Vascular Biocompatibility of a Triple Layered Self Expanding Stent-Graft in a Dog Mode

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jae Ik; Won, Je Hwan; Jang, Eun Ho; Lee, Sung Yeong; Ko, Kwang Tae [Dept. of Radiology, Ajou University School of Medicine, Suwon (Korea, Republic of); Jin, Bo Hwan [Medical Science Research Center, Ajou University School of Medicine, Suwon (Korea, Republic of); Lee, June Woo [Dept. of Radiology, Busan National University College of Medicine, Busan (Korea, Republic of)

    2012-02-15

    To evaluate performance and biocompatibility of a newly designed self-expanding stent graft, which consisted of two nitinol stents and an intervening expanded polytetrafluoroethylene membrane in a dog artery model. Twelve stent grafts were placed in the aorta of 6 dogs (beagle, mean body weight 11 kg) for 4 weeks (n = 4) and 12 weeks (n = 8). Luminal diameters were measured for each segment (the proximal bare, the middle graft, the distal bare) by angiographies after implantation and follow up periods. Percent luminal stenosis based on angiographies, histomorphometric, histologic, and scanning electron microscopic analyses of each segments were performed. Blood flow through the stent grafts was good after implantation and during the follow up period, without thrombotic occlusion or stent graft migration. The mean percent luminal stenosis of the proximal bare, the middle grafted and the distal bare segments after 12 weeks were 13.5%, 3.9%, 9.6% retrospectively. The mean neointimal areas of the middle grafted segment were 4.39 mm{sup 2} (4 week) and 4.92 mm{sup 2} (12 week). Mature endothelialization was evident in over 70% of the area of the stented artery after 4 weeks and in over 90% after 12 weeks. The stent graft was well placed in the attempted area without migration. During the 12-week-follow up period, it showed a good patency without thrombotic occlusion or significant in-stent luminal stenosis. Endothelialization was rapid and nearly complete. Neointima was thin and smooth on the middle graft segment and thicker and irregular on the bare segments.

  13. Vascular Biocompatibility of a Triple Layered Self Expanding Stent-Graft in a Dog Mode

    International Nuclear Information System (INIS)

    Bae, Jae Ik; Won, Je Hwan; Jang, Eun Ho; Lee, Sung Yeong; Ko, Kwang Tae; Jin, Bo Hwan; Lee, June Woo

    2012-01-01

    To evaluate performance and biocompatibility of a newly designed self-expanding stent graft, which consisted of two nitinol stents and an intervening expanded polytetrafluoroethylene membrane in a dog artery model. Twelve stent grafts were placed in the aorta of 6 dogs (beagle, mean body weight 11 kg) for 4 weeks (n = 4) and 12 weeks (n = 8). Luminal diameters were measured for each segment (the proximal bare, the middle graft, the distal bare) by angiographies after implantation and follow up periods. Percent luminal stenosis based on angiographies, histomorphometric, histologic, and scanning electron microscopic analyses of each segments were performed. Blood flow through the stent grafts was good after implantation and during the follow up period, without thrombotic occlusion or stent graft migration. The mean percent luminal stenosis of the proximal bare, the middle grafted and the distal bare segments after 12 weeks were 13.5%, 3.9%, 9.6% retrospectively. The mean neointimal areas of the middle grafted segment were 4.39 mm 2 (4 week) and 4.92 mm 2 (12 week). Mature endothelialization was evident in over 70% of the area of the stented artery after 4 weeks and in over 90% after 12 weeks. The stent graft was well placed in the attempted area without migration. During the 12-week-follow up period, it showed a good patency without thrombotic occlusion or significant in-stent luminal stenosis. Endothelialization was rapid and nearly complete. Neointima was thin and smooth on the middle graft segment and thicker and irregular on the bare segments.

  14. Malignant biliary obstruction: percutaneous use of self-expandable stents

    NARCIS (Netherlands)

    Laméris, J. S.; Stoker, J.; Nijs, H. G.; Zonderland, H. M.; Terpstra, O. T.; van Blankenstein, M.; Schütte, H. E.

    1991-01-01

    A total of 83 self-expandable metallic stents were placed percutaneously in 69 patients for palliation of malignant biliary obstruction. Stent diameter was 1 cm; length, 3.5-10.5 cm. Of the 41 patients with common bile duct obstruction, 27 died 0.2-12 months (median, 3.2 months) after stent

  15. Self-expandable metalic endotracheal stent

    International Nuclear Information System (INIS)

    Do, Young Soo; Cho, Dae Soon; Cho, Kyung Ja; Lee, Young Soo; Lee, Mi Jae

    1993-01-01

    Six bare stents and six covered stents were inserted in the trachea of 12 dogs under general anesthesia. After 1-10 weeks of observation, the dogs were killed, and the trachea and lung were examined grossly and histologically. Pneumonia and stent migration were observed more frequently at covered stent group. Inflammatory change of the trachea was more severe at covered stent group. In conclusion, we believe that it is inadequate to insert silicone covered stent in the tracheobronchial tree. (Author)

  16. Self-expandable metalic endotracheal stent

    Energy Technology Data Exchange (ETDEWEB)

    Do, Young Soo; Cho, Dae Soon; Cho, Kyung Ja; Lee, Young Soo; Lee, Mi Jae [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1993-01-01

    Six bare stents and six covered stents were inserted in the trachea of 12 dogs under general anesthesia. After 1-10 weeks of observation, the dogs were killed, and the trachea and lung were examined grossly and histologically. Pneumonia and stent migration were observed more frequently at covered stent group. Inflammatory change of the trachea was more severe at covered stent group. In conclusion, we believe that it is inadequate to insert silicone covered stent in the tracheobronchial tree. (Author).

  17. Self-expandable stent loaded with {sup 125}I seeds: Feasibility and safety in a rabbit model

    Energy Technology Data Exchange (ETDEWEB)

    Guo Jinhe [Department of Radiology, Zhong-Da Hospital, Southeast University, 87 Dingjiaqiao Road, Nanjing 210009 (China); Teng Gaojun [Department of Radiology, Zhong-Da Hospital, Southeast University, 87 Dingjiaqiao Road, Nanjing 210009 (China)]. E-mail: gjteng@vip.sina.com; Zhu Guangyu [Department of Radiology, Zhong-Da Hospital, Southeast University, 87 Dingjiaqiao Road, Nanjing 210009 (China); He Shicheng [Department of Radiology, Zhong-Da Hospital, Southeast University, 87 Dingjiaqiao Road, Nanjing 210009 (China); Deng Gang [Department of Radiology, Zhong-Da Hospital, Southeast University, 87 Dingjiaqiao Road, Nanjing 210009 (China); He Jie [Department of Radiology, Zhong-Da Hospital, Southeast University, 87 Dingjiaqiao Road, Nanjing 210009 (China)

    2007-02-15

    Objective: To evaluate technical feasibility and acute and subacute radiotolerance of a self-expandable stent loaded with {sup 125}I seeds in the rabbit esophagus. Methods: A self-expandable stent designed for esophageal application was made of 0.16 mm nitinol wire and loaded with {sup 125}I seeds (CIAE-6711). Twenty-seven stents with three different radioactive dosages (n = 9 in each dosage group) were implanted in the esophagus of healthy rabbits, while nine stents alone were used as controls. The stents were perorally deployed into the esophagus under fluoroscopic guidance. Radiological follow-up included plain chest film, CT scan, and barium esophagography which were undertaken in all rabbits of each group at 2, 4, and 8 weeks, respectively, which were correlated to histopathological findings. The stented esophageal segments along with their adjacent tissues were harvested for histopathological examinations. Results: The stent was successfully deployed into the targeted esophageal segment in all rabbits. Neither {sup 125}I seeds dislodged from the stent during the deployment, nor they did during the follow-up period. The greatest (16.2 Gy) absorbed dose was found in the tissue 10 mm from {sup 125}I seeds at 8 weeks. Slight epithelial hyperplasia on the stent surface and submucosal inflammatory process developed at 2 weeks, which reached the peak at 8 weeks after the procedure. Significant thickness of the esophageal muscular layer was found at 8 weeks only in the groups with {sup 125}I seeds. On radiologic follow-up, moderate strictures on both ends of the stents developed at 4 weeks and became severe at 8 weeks after the procedure in all groups. Conclusion: Deployment of a self-expandable stent loaded with {sup 125}I seeds is technically feasible and safe within the first 8 weeks. Acute and subacute radiotolerance of the treated esophagus and its adjacent tissues by {sup 125}I seeds is well preserved in a healthy rabbit model.

  18. Covered Balloon-Expanding Stents in Airway Stenosis.

    Science.gov (United States)

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

    2017-04-01

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

  19. Efficacy of a dexamethasone-eluting nitinol stent on the inhibition of pseudointimal hyperplasia in a transjugular intrahepatic portosystemic shunt: an experimental study in a swine model

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Tae Seok [Korea University Guro Hospital, Seoul (Korea, Republic of); Oh, Joo Hyeogn; Park, Young Koo [Kyung Hee University Hospital, Seoul (Korea, Republic of); Song, Ho Young [University of Ulsan, College of Medicine, Seoul (Korea, Republic of); Park, Sang Joon [Hallym University, College of Medicine, Seoul (Korea, Republic of); Yuk, Sun Hong [Hannam University, Daejeon (Korea, Republic of)

    2005-12-15

    We wanted to evaluate the feasibility and efficacy of using a dexamethasone (DM)-eluting nitinol stent to inhibit the pseudointimal hyperplasia following stent placement in the transjugular intrahepatic portosystemic shunt tract (TIPS) of a swine. Fifteen stents were constructed using 0.15 mm-thick nitinol wire; they were 60 mm in length and 10 mm in diameter. The metallic stents were then classified into three types; type 1 and 2 was coated with the mixture of 12% and 20%, respectively, of DM solution and polyurethane (PU), while type 3 was a bare stent that was used for control study. In fifteen swine, each type of stent was implanted in the TIPS tract of 5 swine, and each animal was sacrificed 2 weeks after TIPS creation. The proliferation of the pseudointima was evaluated both on follow-up portogram and pathologic examination. One TIPS case, using the type 1 stent, and two TIPS cases, using the type 2 stent, maintained their luminal patency while the others were all occluded. On the histopathologic analysis, the mean of the maximum pseudointimal hyperplasia was expressed as the percentage of the stent radius that was patent, and these values were 51.2%, 50% and 76% for the type 1, 2, and 3 stents, respectively. The DM-eluting stent showed a tendency to reduce the development of pseudointimal hyperplasia in the TIPS tract of a swine model with induced-portal hypertension.

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

    Science.gov (United States)

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

    2013-03-01

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

  1. Endovascular therapy of carotid stenosis with self-expandable stent

    International Nuclear Information System (INIS)

    Liu Jianmin; Huang Qinghai; Hong Bo; Xu Yi; Zhao Wenyuan; Zhang Yongwei; Zhang Long; Zhou Xiaoping

    2002-01-01

    Objective: To summarize the experience of endovascular treatment of carotid stenosis with expandable stents. Methods: Fifty-two patients with carotid stenosis who experienced repeated transient ischemic attacks or cerebral infarction were admitted to our hospital. The stenosis was pre-expanded with undetachable balloon, and self-expandable stents were implanted across the stenosis. A balloon catheter was used to further expand stents in 29 patients. Results: The stent was accurately implanted, and total disappearance of stenosis was obtained in 34 patients, the degree of stenosis reduced more than 90% in 16 patients, and more than 70% in 2 patients. The patients recovered well and no complications related to the procedure occurred. None experienced TIA or infarction postoperatively in 52 cases and follow-up imaging in 19 patients (6 - 12 months) demonstrated no restenosis. Conclusion: Endovascular stenting may be a safe and valid choice for the treatment of extracranial carotid stenosis

  2. Expandable metallic stent: experimental and clinical experience in tracheobronchial tree

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Lee, Sang Young; Chung, Jin Young; Han, Young Min; Kim, Jong Soo; Choi, Ki Chul; Hong, Ki Whan; Rhee, Yang Kun [Chonbuk National University Medical School, Jeonju (Korea, Republic of)

    1991-05-15

    To maintain or reestablish an adequate airway in a patient with tracheobronchial narrowing coming from various causes, we constructed self-expanding metallic stents the same way Gianturco did, using them in 2 patients after an experimental study with rabbits. Twenty stents (10mm in diameter fully expanded and 20mm in length) were introduced into the trachea or bronchi of 10 Newzealand rabbits (weight, 2.5-3.0kg) through a 8.5 French Teflon sheath. No difficulties were encountered in the placement of the stents. At follow-up (4-12 weeks), no stent showed migration. Three rabbits died of pneumonia or bronchial perforation. Histologically, mucosal inflammation was noted at the sites of stent placement, and stent wires were covered by proliferated epithelium with intact cilia. During the last 4 months, 2 stents were used in 2 patients, one in a patient with endobronchial tuberculosis (3.0cm in length and 1.0cm in diameter fully expanded) and the other (3.0cm in length and 1.5cm in diameter) in a patient with a subglottic mass. In both patients the stents were successfully placed. Just after the placement of the stents dyspnea subsided in both patients, and there was no mortality or morbidity. These stents seem to be effective in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction.

  3. Expandable metallic stent: experimental and clinical experience in tracheobronchial tree

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Sang Young; Chung, Jin Young; Han, Young Min; Kim, Jong Soo; Choi, Ki Chul; Hong, Ki Whan; Rhee, Yang Kun

    1991-01-01

    To maintain or reestablish an adequate airway in a patient with tracheobronchial narrowing coming from various causes, we constructed self-expanding metallic stents the same way Gianturco did, using them in 2 patients after an experimental study with rabbits. Twenty stents (10mm in diameter fully expanded and 20mm in length) were introduced into the trachea or bronchi of 10 Newzealand rabbits (weight, 2.5-3.0kg) through a 8.5 French Teflon sheath. No difficulties were encountered in the placement of the stents. At follow-up (4-12 weeks), no stent showed migration. Three rabbits died of pneumonia or bronchial perforation. Histologically, mucosal inflammation was noted at the sites of stent placement, and stent wires were covered by proliferated epithelium with intact cilia. During the last 4 months, 2 stents were used in 2 patients, one in a patient with endobronchial tuberculosis (3.0cm in length and 1.0cm in diameter fully expanded) and the other (3.0cm in length and 1.5cm in diameter) in a patient with a subglottic mass. In both patients the stents were successfully placed. Just after the placement of the stents dyspnea subsided in both patients, and there was no mortality or morbidity. These stents seem to be effective in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction

  4. Effectiveness of a new nitinol stent manufactured locally, in the treatment of the obstruction malign esophageal

    International Nuclear Information System (INIS)

    Castano, Rodrigo; Ruiz, Mario; Juliao Banos, Fabian; Sanin, Eugenio; Alvarez, Oscar; Lopera, Jorge

    2003-01-01

    Esophageal strictures and esophasorespiratory fistulas are complications of malignant esophageal tumors and benign conditions, which are difficult to manage. The efficacy of a locally (Medellin-Colombia) produced self- expanding metal stents (SEMS) for palliation of malignant esophageal strictures and fistulas was investigated prospectively. Eighty-one SEMS were inserted in 77 patients, 73 patients with malignant esophageal stricture (l0 with fistula) and 4 benign. Our series included 45 men and 32 women, of whom median age was 65 years. Sixty-three stents were inserted for malignant strictures, ten for esophagus-tracheal fistula, and four for benign conditions. Stents were inserted endoscopically only in 83% and under endoscopy and fluoroscopic control in 17%. SEMS implantation was technically successful in 100%. A second stentins was needed in four patients. Median dysphasia score improved from 2,8 to 1,4 (p<0,0l) the covered SEMS was successful in completely sealing 100% of the fistulas. Complication occurred in 28,4% patients. Procedure-related mortality was 0%. We conclude that treatment of malignant esophageal obstructions, including esophasorespiratory fistulas, with SEMS locally produced is a good alternative palliative; Furthermore SEMS implantation seems safe in the case of benign stenoses

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

    Directory of Open Access Journals (Sweden)

    Sergio Puértolas

    2013-01-01

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

  6. An experimental study on expandable endovascular metallic stents in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Kim, Hak Nam [Chonbuk National University College of Medicine, Chonju (Korea, Republic of)

    1990-12-15

    We constructed an expandable endovascular metallic stent in the same way as Giamturco did. Experiments were made to test the ability of these stents to be used in the vessels. A total of 20 stents were passed through a 8.5 French teflon sheath into the normal abdominal aorta. IVC, and iliac artery of four adult dogs for 4 weeks to 12 weeks; 8 stents (10 mm in diameter fully expanded and 20 mm in length) in the abnormal aorta, 7 stents (12 mm/20 mm) in the IVC, and 5 stents (8 mm/20 mm) in the iliac artery. All but two stents showed no migration, and one complete occlusion occurred in right iliac artery of a dog. Histologically, stents wires were covered by neo-intimal proliferation. The side branches of the main vessels remained patent, even stent wires across their orifices. These metallic stents may be used as an endovascular graft material in the nonsurgical treatment of several forms of vascular disease.

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

    Science.gov (United States)

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

    2014-04-01

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

  8. Self-expanding nanoplatinum-coated nitinol devices for atrial septal defect and patent ductus arteriosus closure: a swine model.

    Science.gov (United States)

    Lertsapcharoen, Pornthep; Khongphatthanayothin, Apichai; La-orkhun, Vidhavas; Supachokchaiwattana, Pentip; Charoonrut, Phingphol

    2006-01-01

    Our purpose was to evaluate self-expanding nanoplatinum-coated nitinol devices for transcatheter closure of atrial septal defects and patent ductus arteriosus in a swine model. The devices were braided from platinum-activated nitinol wires and filled with polyester to enhance thrombogenicity. The platinum activation of the nitinol wires was carried out with the help of Nanofusion technology. The coating of platinum covers the exposed surface of the nitinol wires and prevents the release of nickel into the blood stream after the implantation of the device but does not affect its shape memory, which makes the device self-expanding after it is loaded from the catheter. Atrial septal defects were created in 12 piglets by balloon dilation of the patent foramen ovale. The size of the device was selected on the basis of the diameter of the balloon and the size of the defect, measured by transthoracic echocardiography. The devices were successfully deployed in all 12 piglets under fluoroscopic study. Transthoracic color Doppler echocardiograms showed complete closure of the atrial septal defect within 15 minutes of device implantation. Twelve patent ductus arteriosus closure devices were deployed in the right or left subclavian arteries in 10 piglets. Angiograms showed complete occlusion of the subclavian arteries within a few minutes of device deployment. In the atrial septal defect cases, the autopsy findings showed complete organizing fibrin thrombus formation and complete neo-endothelialization on the outer surface of the devices within one week and six weeks of implantation, respectively. The use of self-expanding nanoplatinum-coated nitinol devices for the transcatheter closure of atrial septal defects and patent ductus arteriosus is feasible. The excellent occlusion result and complete neo-endothelialization of the devices in the swine model is an indication of the potential of these devices in human application.

  9. Removal of retrievable self-expandable urethral stents: experience in 58 stents

    International Nuclear Information System (INIS)

    Shin, Ji Hoon; Song, Ho-Young; Kim, Jin Hyoung; Ko, Heung-Kyu; Kim, Yong Jae; Woo, Chul-Woong; Kim, Tae-Hyung; Ko, Gi-Young; Yoon, Hyun-Ki; Sung, Kyu-Bo; Park, Hyungkeun

    2006-01-01

    The purpose of this study was to retrospectively evaluate the safety and efficacy of removing retrievable self-expandable urethral stents using a retrieval hook wire. Under fluoroscopic guidance, the removal of 58 polyurethane or PTFE (polytetrafluoroethylene)-covered stents was attempted in 33 patients using a retrieval hook wire. Indications for removal were elective removal (n=21), stent migration (n=19), formation of tissue hyperplasia around or inside of the stent (n=14), stent deformity (n=3), and severe pain (n=1). The mean time the stents remained in place was 64.8±42.9 days (range, 1-177 days). Fifty-six (97%) of the 58 stents were successfully removed using the retrieval hook wire despite the following difficulties; hook wire disconnection (n=2), untied drawstrings (n=3), and polyurethane membrane disruption/separation (n=4). The removal procedure using a retrieval hook wire failed in two stents (3%) which had migrated into the urinary bladder. One of the two stents with migration into the urinary bladder was removed using a snare through the cystostomy route. The overall complication rate was 14% (seven hematuria cases and one urethral tear case), and all were minor and spontaneously resolved without further treatment. In conclusion, removal of retrievable urethral stents using a retrieval hook wire was safe and effective despite some technical difficulties. It is a useful method for allowing temporary stent placement and solving various complications of stent use. (orig.)

  10. Removal of retrievable self-expandable urethral stents: experience in 58 stents

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ji Hoon; Song, Ho-Young; Kim, Jin Hyoung; Ko, Heung-Kyu; Kim, Yong Jae; Woo, Chul-Woong; Kim, Tae-Hyung; Ko, Gi-Young; Yoon, Hyun-Ki; Sung, Kyu-Bo [Asan Medical Center, Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Seoul (Korea); Park, Hyungkeun [Asan Medical Center, Department of Urology, University of Ulsan College of Medicine, Seoul (Korea)

    2006-09-15

    The purpose of this study was to retrospectively evaluate the safety and efficacy of removing retrievable self-expandable urethral stents using a retrieval hook wire. Under fluoroscopic guidance, the removal of 58 polyurethane or PTFE (polytetrafluoroethylene)-covered stents was attempted in 33 patients using a retrieval hook wire. Indications for removal were elective removal (n=21), stent migration (n=19), formation of tissue hyperplasia around or inside of the stent (n=14), stent deformity (n=3), and severe pain (n=1). The mean time the stents remained in place was 64.8{+-}42.9 days (range, 1-177 days). Fifty-six (97%) of the 58 stents were successfully removed using the retrieval hook wire despite the following difficulties; hook wire disconnection (n=2), untied drawstrings (n=3), and polyurethane membrane disruption/separation (n=4). The removal procedure using a retrieval hook wire failed in two stents (3%) which had migrated into the urinary bladder. One of the two stents with migration into the urinary bladder was removed using a snare through the cystostomy route. The overall complication rate was 14% (seven hematuria cases and one urethral tear case), and all were minor and spontaneously resolved without further treatment. In conclusion, removal of retrievable urethral stents using a retrieval hook wire was safe and effective despite some technical difficulties. It is a useful method for allowing temporary stent placement and solving various complications of stent use. (orig.)

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

    Science.gov (United States)

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

    1996-09-01

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

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

    Science.gov (United States)

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

    2005-07-01

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

  13. Esophagojejunal anastomotic leak managed with self expandable metallic stent

    Directory of Open Access Journals (Sweden)

    Arvind Madurandagam Annapillai

    2013-01-01

    Full Text Available Esophagealjejunal anastomotic leak after gastrectomy is a serious surgical emergency with high mortality. This report describes a 57-year-old male with esophagojejunal anastomotic leak following total gastrectomy for gastric cancer and was managed successfully with self-expandable metallic stent. To our knowledge this is the first such report from India. This case report highlights the need of interdisciplinary coordination in managing this difficult clinical situation. Endotherapy with self-expandable metallic stent (SEM provided twin benefits of improving respiratory embarrassment and the joy of eating. Therapy of such difficult cases must be individualized; however, and SEM stent usage is a viable option

  14. Use of a Nitinol Wire Stent for Management of Severe Tracheal Stenosis in an Eclectus Parrot (Eclectus roratus).

    Science.gov (United States)

    Mejia-Fava, Johanna; Holmes, Shannon P; Radlinsky, MaryAnn; Johnson, Dan; Ellis, Angela E; Mayer, Jörg; Schnellbacher, Rodney; Divers, Stephen J

    2015-09-01

    A 25-year-old, female eclectus parrot (Eclectus roratus) presented for dyspnea 3 weeks after anesthesia and surgery for egg yolk coelomitis. Radiography, computed tomography, and tracheoscopy revealed multiple tracheal strictures spanning a length of 2.6 cm in the mid to distal trachea. Histopathologic examination revealed mild fibrosis, inflammation, and hyperplasia consistent with acquired tracheal strictures. Tracheal resection was not considered possible because of the length of the affected trachea. The strictures were resected endoscopically, and repeated balloon dilation under fluoroscopic guidance over the course of 10 months resulted in immediate but unsustained improvement. Computed tomography was used to measure the stenotic area. A 4 × 36-mm, custom-made, nitinol wire stent was inserted into the trachea under fluoroscopic guidance. After stent placement, intermittent episodes of mild to moderate dyspnea continued, and these responded to nebulization with a combination of saline, acetylcysteine, and dexamethasone. Multiple attempts to wean the patient off nebulization therapy and to switch to a corticosteroid-free combination were unsuccessful. The parrot eventually developed complications, was euthanatized, and necropsy was performed. Histologically, the tracheal mucosa had widespread erosion to ulceration, with accumulation of intraluminal exudate and bacteria, severe degeneration of skeletal muscle and tracheal rings, prominent fibrosis, and mild to moderate, submucosal inflammation. Clinicopathologic findings in this case suggested tracheomalacia, which has not been previously described in birds. Custom-made tracheal stents can be used for severe tracheal stenosis in birds when tracheal resection and anastomosis is not possible. Complications of tracheal stent placement in birds may include tracheitis and tracheomalacia. To our knowledge, this is the first report of tracheal stent placement in an avian species.

  15. Long-term results after carotid artery stenting. Restenosis after carotid artery stenting using self-expandable stent

    International Nuclear Information System (INIS)

    Matsumoto, Yasushi; Furui, Eisuke; Tsuboi, Ken; Takahashi, Akira; Ezura, Masayuki

    2008-01-01

    Carotid artery stenting has emerged as an acceptable treatment alternative in patients with carotid artery stenosis. Although early clinical results of carotid artery stenting have shown promise, long, term clinical results remain less certain. We report the frequency, management, and clinical results of in-stent restenosis after carotid artery stenting using a self-expandable stent. Between August 1998 and September 2004, 80 carotid artery stenting procedures in 78 patients were performed. We evaluated 76 of the 80 procedures in 75 of the 78 patients treated during this period who had a minimum 6-month clinical and imaging (ultrasound and/or magnetic resonance angiography) follow-up. Recurrent stenosis (≥50%) after carotid artery stenting occurred in 3 (3.9%) patients. The recurrent stenosis occurred within one year after the procedure in all cases. The low rate of in-stent restenosis using self-expandable stent suggested that carotid artery stenting may be an effective alternative treatment for carotid artery stenosis, but more data of long-term follow-up are required. (author)

  16. Nitinol memmo-alloy stents for benign and malignant tracheal stensis

    International Nuclear Information System (INIS)

    Wang Zhongmin; Wu Chaoxian; Gong Ju; Zheng Yunfeng; Gu Xuezhang

    2005-01-01

    Objective: To observe the therapeutic and side effects of tracheal stents in tracheal stenosis caused by tracheal malacia and malignant tumours. Methods: Twenty-five patients treated with tracheal stents were retrospectively analyzed. Results: Tracheal stents have been implanted successfully in twenty-five patients through fiberbronchoscope or tracheal intubation, and dyspnoea improved greatly after the procedure. Conclusions: Tracheal stents can relieve symptoms and improve the life quality in patients with tracheal stenosis caused by malignant tumors or tracheal malacia. (authors)

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

    Science.gov (United States)

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

    2008-01-01

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

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

    Science.gov (United States)

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

    2015-06-01

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

  19. In Vitro Comparison of Self-Expanding Versus Balloon-Expandable Stents in a Human Ex Vivo Model

    International Nuclear Information System (INIS)

    Grenacher, Lars; Rohde, Stefan; Gaenger, Ellen; Deutsch, Jochen; Kauffmann, Guenter W.; Richter, Goetz M.

    2006-01-01

    The objective was to compare the radial strength and expansile precision of self-expanding stents and balloon-expandable stents in a human cadaver bifurcation model. Seven different self-expanding (LUMINEXX, JOSTENT SelfX, JOSTENT SelfX hrf, Sinus-Repo, Sinus SuperFlex, Easy Wallstent, SMART) and four different balloon-expandable stent models (Palmaz, Sinus Stent, SAXX Medium, JOSTENT peripheral), each type 10 stents (total n = 110 stents) were implanted into the common iliac arteries of human cadaver corpses. The maximum stent diameter was 10 mm for all models. After stent implantation, the specimens were filled with silicone caoutchouc. After 24 h, the vascular walls including the stents were removed from the hardened casts. Diameters were taken and the weight of the cast cylinders was measured in air and in purified water to calculate the volume of the bodies (according to Archimedes Law) as a relative but precise degree for the radial strength of the implanted stents. The cylindrical casts of the self-expanding stents showed lower mean diameters (8.2 ± 1.0 mm) and mean volumes (0.60 ± 0.14 ml/cm) than in the balloon-expandable stent group (10.1 ± 0.3 mm and 0.71 ± 0.04 ml/cm, respectively; p < 0.01). The nominal maximum diameter of 10 mm was not achieved in any of the self-expanding stents, but this was achieved in more than 70% (29/40) of the balloon-expandable stent specimens (p < 0.05). The variation between achieved volumes was significantly larger in self-expanding (range: 0.23-0.78 ml/cm) than in balloon-expandable stents (range: 0.66-0.81 ml/cm; p < 0.05). Self-expanding stents presented considerably lower radial expansion force and lower degree of precision than balloon-expandable stents

  20. Esophagorespiratory fistula: treatment with self-expanding covered stent

    International Nuclear Information System (INIS)

    Zang Jian; Dou Yongchong; Wang Zheng; Kong Jian

    2002-01-01

    Objective: To evaluate self-expanding covered stent in the management of esophagorespiratory fistula. Methods: A self-expanding esophageal covered stent was implanted under fluoroscopic guidance in 13 patients with esophagorespiratory fistula. In this series patients aged 31-73 years (60.2 years in average). All patients had a pre-procedure fast of 6-41 days (17.3 days in average), in which 12 patients had pulmonary infection. Results: All fistulas were excluded and swallowing function was restored. No stend-related complication was observed. Pulmonary infection was managed in 10 patients out of 13. The mean survived time was 33.3 wks (1-178 wks) in follow-up. Conclusion: Covered self-expanding stent implantation is a safe and effective treatment of ERF

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

    Science.gov (United States)

    Blero, Daniel; Huberty, Vincent; Devière, Jacques

    2015-03-01

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

  2. A new intratracheal stent made from nitinol, an alloy with "shape memory effect".

    Science.gov (United States)

    Vinograd, I; Klin, B; Brosh, T; Weinberg, M; Flomenblit, Y; Nevo, Z

    1994-05-01

    Temporary or permanent tracheal splinting in pediatric patients may be indicated in tracheomalacia or bronchomalacia, repair of congenital tracheal stenosis, and after tracheal resection. This study presents the results of the development of a new intraluminal airway stent made from titanium alloy, a metal with "shape memory effect". At low temperatures (martensitic state) the titanium alloy stent can be fashioned into a specific shape; then when heated to a higher temperature (austenitic state) the stent alters its shape, only to regain its original shape when recooled to the lower temperature. The stent, connected to a small electric power supply, was introduced into 20 young rabbits with the use of a 2.5 cm rigid bronchoscope. After implantation in the martensitic state the stent was warmed to 40 degrees C, the austenitic state, by an electric current of 1.5 to 3 ampere for 1 to 2 seconds. After a period of 8 to 10 weeks the stent was removed (in its martensitic state) through the same-sized bronchoscope after being cooled with 3 to 4 ml of 80% alcohol solution at 6 degrees C. No signs of airway obstruction developed in any of the animals after implantation or extraction of the stent. The biomechanical properties of the trachea, as shown by strain measurements with the use of incremental forces, showed significant differences between the stented and unstented segments (p stent adequately fulfilled the requirements of a temporary intraluminal airway splint, and because of its unique feature of shape memory effect the stent could be inserted, fixed, and removed easily, even in very small airways.

  3. Stent Fracture and Reocclusion After Placement of a Single Self-Expanding Stent in the Common Iliac Artery and Endovascular Treatment

    International Nuclear Information System (INIS)

    Higashiura, Wataru; Sakaguchi, Shoji; Morimoto, Kengo; Kichikawa, Kimihiko

    2008-01-01

    We present a case of fracture of a single self-expanding stent placed in the common iliac artery (CIA). An 80-year-old woman underwent placement of a self-expanding stent for CIA occlusion. Stent fracture and reocclusion were detected after 18 months. Successful revascularization was achieved using a stent-in-stent maneuver. The possibility of stent fracture with reocclusion should be considered following treatment with a single self-expanding stent for CIA occlusion.

  4. Clinical impact and risk stratification of balloon angioplasty for femoropopliteal disease in nitinol stenting era: Retrospective multicenter study using propensity score matching analysis

    Directory of Open Access Journals (Sweden)

    Taketsugu Tsuchiya

    2016-07-01

    Full Text Available Objective: Nitinol stenting could bring the better outcome in endovascular therapy for femoropopliteal disease. However, it might be expected that recent marked advances in both device technology and operator technique had led to improved efficacy of balloon angioplasty even in this segment. The aims of this study were to evaluate the clinical impact of balloon angioplasty for femoropopliteal disease and make risk stratification clear by propensity score matching analysis. Methods: Based on the multicenter retrospective data, 2758 patients (balloon angioplasty: 729 patients and nitinol stenting: 2029 patients, those who underwent endovascular therapy for femoropopliteal disease, were analyzed. Results: The propensity score matching procedure extracted a total of 572 cases per group, and the primary patency rate of balloon angioplasty and nitinol stenting groups after matching was significantly the same (77.2% vs 82.7% at 1 year; 62.2% vs 64.3% at 3 years; 47.8% vs 54.3% at 5 years. In multivariate Cox hazard regression analysis, significant predictors for primary patency were diabetes mellitus, regular dialysis, cilostazol use, chronic total occlusion, and intra-vascular ultra-sonography use. The strategy of balloon angioplasty was not evaluated as a significant predictor for the primary patency. After risk stratification using five items (diabetes mellitus, regular dialysis, no use of intra-vascular ultra-sonography, chronic total occlusion, and no use of cilostazol: the DDICC score, the estimated primary patency rates of each group (low, DDICC score 0–2; moderate, DDICC score 3; high risk, DDICC score 4–5 were 88.6%, 78.3%, and 63.5% at 1 year; 75.2%, 60.7%, and 39.8% at 3 years; and 66.0%, 47.1%, and 26.3% at 5 years (p < 0.0001. The primary patency rate of balloon angioplasty and nitinol stenting groups was significantly the same in each risk stratification. Conclusion: This study suggests that balloon angioplasty does

  5. New expandable metallic stents: An experimental study in vessels of dogs

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Jung Min; Chung, Jin Young; Chung, Gyung Ho; Kim, Bog Yi; Kuh, Ja Houng

    1992-01-01

    Three-types of expandable metallic stents were constructed to evaluate the differences between the stents: one, formed in a cylindrical zigzag pattern wth stainless steel wire (Gianturco stent), another, made by coating the Gianturco stent with silicone rubber (Silicone stent), the third, made by coating the Gianturco stent with 24 carat gold (Gold stent) for tissue acceptance. A total of 69 stents (each 23 stents of Gianturco, Silicone, and Gold stents) of 8-12 mm in diameter and 20 mm long were placed into normal abdominal aorta, inferior vena cava and lilac artery of nine adults dogs for 2 weeks to 11 months. It was more difficult to introduce Silicone stent into an introducing sheath than Gianturco or Gold stent due to the thickness of silicone rubber. Four Gianturco stents and three Silicone stents showed migration but Gold stent did not. Luminal narrowing or occlusion was noted in 3 Silicone stents. In 2 Gianturco stents, and in 1 Gold stent. Neointimal proliferation over the stent wires was more rapid and even in Gold stent than Silicone or Gianturco stent. Although further study is needed, Gold stent seems to be better than Gianturco or Silicone stent as an endovascular graft material

  6. New expandable metallic stents: An experimental study in vessels of dogs

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Lee, Jung Min; Chung, Jin Young; Chung, Gyung Ho; Kim, Bog Yi; Kuh, Ja Houng [Chunbuk National University Medical School, Chunju (Korea, Republic of)

    1992-07-15

    Three-types of expandable metallic stents were constructed to evaluate the differences between the stents: one, formed in a cylindrical zigzag pattern wth stainless steel wire (Gianturco stent), another, made by coating the Gianturco stent with silicone rubber (Silicone stent), the third, made by coating the Gianturco stent with 24 carat gold (Gold stent) for tissue acceptance. A total of 69 stents (each 23 stents of Gianturco, Silicone, and Gold stents) of 8-12 mm in diameter and 20 mm long were placed into normal abdominal aorta, inferior vena cava and lilac artery of nine adults dogs for 2 weeks to 11 months. It was more difficult to introduce Silicone stent into an introducing sheath than Gianturco or Gold stent due to the thickness of silicone rubber. Four Gianturco stents and three Silicone stents showed migration but Gold stent did not. Luminal narrowing or occlusion was noted in 3 Silicone stents. In 2 Gianturco stents, and in 1 Gold stent. Neointimal proliferation over the stent wires was more rapid and even in Gold stent than Silicone or Gianturco stent. Although further study is needed, Gold stent seems to be better than Gianturco or Silicone stent as an endovascular graft material.

  7. Afterloading intracavitary irradiation and expanding stent for malignant biliary obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimura, Hitoshi; Sakaguchi, Hiroshi; Yoshioka, Tetsuya and others

    1989-02-01

    A double lumen catheter was developed as an apllicator for the remote afterloading (RALS) of /sup 60/Co source for the intracavitary irradiation of an obstructed common bile duct caused by carcinoma of the gallbladder. This was followed by the placement of nylon-covered expandable metallic stents to maintain patency. This combination effectively provided palliation. (author).

  8. A new Nitinol stent for use in superior vena cava syndrome

    DEFF Research Database (Denmark)

    Andersen, Poul Erik; Midtgaard, Annette; Brenøe, Anne-Sofie

    2015-01-01

    AIM: The aim of the study was to assess the early clinical experience with the Zilver Vena stent in treating patients with malignant superior vena cava syndrome. METHODS: Demographic, procedural, and follow-up data of 12 patients (seven women; mean age 69 years) treated for superior vena cava...... syndrome with in all 21 Zilver Vena stents between March 2012 and October 2013 were retrospectively reviewed. All cavographies and contrast enhanced CT related to the treatment and during follow-up were evaluated and the patients had clinical follow-up until dead. They were all in terminal state...... at the time of stent deployment. RESULTS: All patients had superior vena cava obstruction and clinical superior vena cava syndrome caused by malignant expansive mediastinal disease (eight patients non-small cell lung cancer and four small cell lung cancer). The technical success with deployment of the stents...

  9. Anchoring barbs and balloon expandable stents: what is the risk of perforation and failed stent deployment?

    Science.gov (United States)

    Bown, M J; Harrison, G J; How, T V; Brennan, J A; Fisher, R K; Vallabhaneni, S R; McWilliams, R G

    2012-09-01

    Balloon expandable stents may on occasion be deployed in close proximity to the anchoring barbs of endovascular grafts. The aim of this study was to determine the risk and effect of balloon perforation by anchoring barbs and to assess whether these risks are different if the balloon is protected by a covered stent mounted upon it. A bench-top model was developed to mimic the penetration of anchoring barbs into the lumen of medium sized blood vessels. The model allowed variation of angle and depth of vessel penetration. Both bare balloons and those with covered stents mounted upon them were tested in the model to determine whether there was a risk of perforation and which factors increased or decreased this risk. All combinations of barb angle and depth caused balloon perforation but this was most marked when the barb was placed perpendicular to the long axis of the balloon. When the deployment of covered stents was attempted balloon perforation occurred in some cases but full stent deployment was achieved in all cases where the perforation was in the portion of the balloon covered by the stent. The only situation in which stent deployment failed was where the barb was intentionally placed in the uncovered portion of the balloon. This resulted in only partial deployment of the stent. Balloon rupture is a distinct possibility when deploying balloon-expandable stents in close proximity to anchoring barbs. Care should be taken in this circumstance to ensure that the barb is well away from the uncovered portion of the balloon. Copyright © 2012 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2017-10-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S; Li, Z [University of Florida Proton Therapy Institute, Jacksonville, FL (United States); Jalaj, S; McGaw, C; B K, John; J S, Scolapio; J C, Munoz [Division of Gastoenterology, Department of Medicine, University of Florida, Jacksonville, FL (United States)

    2014-06-01

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

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

    Science.gov (United States)

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

    2005-12-01

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

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

    Science.gov (United States)

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

    2018-03-01

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

  14. Self expandable polytetrafluoroethylene stent for carotid blowout syndrome.

    Science.gov (United States)

    Tatar, E C; Yildirim, U M; Dündar, Y; Ozdek, A; Işik, E; Korkmaz, H

    2012-01-01

    Carotid blowout syndrome (CBS) is an emergency complication in patients undergoing treatment for head and neck cancers. The classical management of CBS is the ligation of the common carotid artery, because suturing is not be possible due to infection and necrosis of the field. In this case report, we present a patient with CBS, in whom we applied a self-expandable polytetrafluoroethylene (PTFE) stent and observed no morbidity. Endovascular stent is a life-saving technique with minimum morbidity that preserves blood flow to the brain. We believe that this method is preferable to ligation of the artery in CBS.

  15. Fracture of an endoluminal nitinol stent used in the treatment of tracheal collapse in a dog.

    Science.gov (United States)

    Mittleman, Elise; Weisse, Chick; Mehler, Stephen J; Lee, Justine A

    2004-10-15

    A 5-year-old castrated male Pomeranian was evaluated because of severe dyspnea and coughing, and a diagnosis of complete, static collapse of the trachea at the thoracic inlet was made. After failure to improve with medical management alone, an endoluminal tracheal stent was placed, which resulted in resolution of signs. Ten weeks after stent placement, the dog underwent tracheal resection and anastomosis because the stent had fractured at the level of the thoracic inlet. One year after surgery, the dog was doing well and required treatment with hydrocodone infrequently. Compared with other surgical treatment options, placement of an endoluminal tracheal stent is a relatively noninvasive intervention that can provide effective relief from the clinical signs associated with tracheal collapse in dogs. Implantation of endoluminal tracheal stents may be associated with complications; therefore, the procedure may best be regarded as a salvage procedure for dogs with end-stage disease that are refractory to appropriate medical management, have extensive collapse of the intrathoracic portion of the trachea, or are poor candidates for surgery.

  16. Mechanical characteristics of self-expandable metallic stents: in vitro study with three types of stress

    International Nuclear Information System (INIS)

    Lee, Byung Hee; Kim, Kie Hwan; Chin, Soo Yil

    1998-01-01

    To obtain objective and comparable data for mechanical characteristics of self-expandable metallic stents widely used in the treatment of biliary obstruction. The stents tested were the 6 and 8 mm-band Hanaro spiral stent, Gianturco-Rosch Z stent, Wallstent, Ultraflex stent, and Memotherm stent. Each was subjected to three types of load:point, area, and circular. We analyzed their mechanical characteristics (resistance force, expansile force, and elasticity) according to these three types of stress. With regard to point loads, the Memotherm stent showed the highest resistance force and expansile force. The 8 mm-band Hanaro stent showed the lowest resistance force and the Gianturco-Rosch Z stent and Ultraflex stent showed lower expansile force. With regard to area loads, the Ultraflex stent showed the highest resistance force. The 6 mm-band Hanaro stent, Gianturco-Rosch Z stent, and Ultraflex stent showed higher expansile force. The 8 mm-band Hanaro stent showed the lowest value in both resistance force and expansile force. For circular loads, the Memotherm stent showed the highest resistance force and the Ultraflex stent and Wallstent showed lower value. Under all types of stress, the Hanaro stent and Memotherm stent were completely elastic, and the Ultraflex stent and Wallstent showed a wide gap between resistance force and expansile force. In clinical practice, awareness of the mechanical characteristics of each stent might help in choosing the one which is most suitable, according to type of biliary obstruction. =20

  17. Mechanical characteristics of self-expandable metallic stents: in vitro study with three types of stress

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Hee; Kim, Kie Hwan; Chin, Soo Yil [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1998-09-01

    To obtain objective and comparable data for mechanical characteristics of self-expandable metallic stents widely used in the treatment of biliary obstruction. The stents tested were the 6 and 8 mm-band Hanaro spiral stent, Gianturco-Rosch Z stent, Wallstent, Ultraflex stent, and Memotherm stent. Each was subjected to three types of load:point, area, and circular. We analyzed their mechanical characteristics (resistance force, expansile force, and elasticity) according to these three types of stress. With regard to point loads, the Memotherm stent showed the highest resistance force and expansile force. The 8 mm-band Hanaro stent showed the lowest resistance force and the Gianturco-Rosch Z stent and Ultraflex stent showed lower expansile force. With regard to area loads, the Ultraflex stent showed the highest resistance force. The 6 mm-band Hanaro stent, Gianturco-Rosch Z stent, and Ultraflex stent showed higher expansile force. The 8 mm-band Hanaro stent showed the lowest value in both resistance force and expansile force. For circular loads, the Memotherm stent showed the highest resistance force and the Ultraflex stent and Wallstent showed lower value. Under all types of stress, the Hanaro stent and Memotherm stent were completely elastic, and the Ultraflex stent and Wallstent showed a wide gap between resistance force and expansile force. In clinical practice, awareness of the mechanical characteristics of each stent might help in choosing the one which is most suitable, according to type of biliary obstruction. =20.

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

    Science.gov (United States)

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

    2013-01-01

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

  19. Comparison of Self-Expanding Polyethylene Terephthalate and Metallic Stents Implanted in Porcine Iliac Arteries

    International Nuclear Information System (INIS)

    Wilczek, Krzysztof; Scheerder, Ivan de; Wang Kai; Verbeken, Eric; Piessens, Jan

    1996-01-01

    Purpose: Comparison of the biocompatibility of self-expanding polyethylene terephthalate (PET) stents with self-expanding metallic stents (Wallstents). Methods: Diameter- and length-matched PET stents and Wallstents were symmetrically implanted in the paired iliac arteries of 13 crossbred domestic swine. Stent deployment was studied angiographically and with intravascular ultrasound immediately after stent implantation. The angiographic stented lumen diameter was measured using quantitative vessel analysis before, immediately after stenting, and at 6-week follow-up. Cross-section histopathology and area morphometry were performed. Results: Immediately poststenting, intravascular ultrasound revealed proximal dislocation of 5 of the 13 PET stents, whereas all metal stents were firmly embedded at the implantation site. At 6-week follow-up, three of the remaining PET stents were totally or subtotally occluded by organized thrombus, whereas all metal stents were patent. Compared with immediately poststenting, the angiographic lumen diameter within the five remaining PET stents was reduced by 30%, and that of the metallic stents was virtually unaltered (p < 0.02). This observation was confirmed by postmortem morphometry, wherein the PET-stented vessel segments a diameter stenosis of 40% was measured vs only 9% in the metallic stents (p < 0.0001). Conclusion: PET-stent deployment is difficult to control due to the lack of radiopacity of this stent. PET stents seem to be more thrombogenic and lead to significantly more neointimal proliferation than metallic stents

  20. Management of malignant biliary obstruction: Technical and clinical results using an expanded polytetrafluoroethylene fluorinated ethylene propylene (ePTFE/FEP)-covered metallic stent after 6-year experience

    Energy Technology Data Exchange (ETDEWEB)

    Fanelli, Fabrizio; Orgera, Gianluigi; Bezzi, Mario; Rossi, Plinio; Allegritti, Massimiliano; Passariello, Roberto [University of Rome, Department of Radiological Sciences, Rome (Italy)

    2008-05-15

    To evaluate the efficacy and safety of an expanded polytetrafluoroethylene-fluorinated ethylene-propylene (ePTFE/FEP)-covered metallic stent in the management of malignant biliary obstruction. Eighty consecutive patients with malignant common bile duct strictures were treated by placement of 83 covered metallic stents. The stent-graft consists of an inner ePTFE/FEP lining and an outer supporting structure of nitinol wire. Clinical evaluation, assessment of serum bilirubin and liver enzyme levels were analyzed before biliary drainage, before stent-graft placement and during the follow-up period at 1, 3, 6, 9 and 12 months. Technical success was obtained in all cases. After a mean follow-up of 6.9{+-}4.63 months, the 30-day mortality rate was 14.2%. Survival rates were 40% and 20.2% at 6 and 12 months, respectively. Stent-graft patency rates were 95.5%, 92.6% and 85.7% at 3, 6 and 12 months, respectively. Complications occurred in five patients (6.4%); among these, acute cholecystitis was observed in three patients (3.8%). A stent-graft occlusion rate of 9% was observed. The percentage of patients undergoing lifetime palliation (91%) and the midterm patency rate suggest that placement of this ePTFE/FEP-covered stent-graft is safe and highly effective in achieving biliary drainage in patients with malignant strictures of the common bile duct. (orig.)

  1. Primary stent placement for recanalization of iliac artery occlusions: Using a self-expanding spiral stent

    International Nuclear Information System (INIS)

    Kim, Jae-Kyu; Kim, Yun-Hyeon; Chung, Sang-Yeung; Kang, Heoung-Keun

    1999-01-01

    Purpose: To report the clinical results for recanalizations of an occluded iliac artery by a self-expanding spiral stent.Methods: We attempted to recanalize 36 iliac artery occlusions in 34 patients [33 men, 1 woman, aged 51-75 years (average 61.6 years)]. The average lesion length was 6.92 cm (range 1-14 cm). The patients's chief complaints were intermittent claudication and resting pain. Fontaine classification was assigned before and after the procedure. Technical and clinical success were also analyzed.Results: Forty-five stents were successfully deployed in 34 patients. All 36 lesions (13 in the external iliac artery, 12 in the common iliac artery, and 11 in both) were patently recanalized on angiography. The follow-up period ranged from 6 months to 36 months (mean 11.9 months). Fourteen stents (39%) with incomplete expansion were dilated with a balloon catheter. Good technical (100%) and clinical (94%) results were obtained. The only complication was one hematoma at the puncture site. Reocclusions were noted in two lesions (5%) at 1 week and 15 months, respectively.Conclusion: A self-expanding spiral stent is a safe and effective device for recanalization of an iliac artery occlusion as the primary stent without any previous intervention.

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

    Science.gov (United States)

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

    2016-02-14

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

  3. Pancreatitis-Associated Splenic Artery Pseudoaneurysm: Endovascular Treatment with Self-Expandable Stent-Grafts

    International Nuclear Information System (INIS)

    Brountzos, Elias N.; Vagenas, Kostantinos; Apostolopoulou, Sotiria C.; Panagiotou, Irene; Lymberopoulou, Dimitra; Kelekis, Dimitrios A.

    2003-01-01

    We present a patient with a splenic arterypseudoaneurysm (SAPA) treated with placement of self-expandable stent-grafts. The procedure was complicated by stent-graft migration,but successful management resulted in lasting exclusion of the SAPA,while the patency of the splenic artery was preserved. This is the first report of self-expandable stent-graft treatment of SAPA

  4. Square Stent: A New Self-Expandable Endoluminal Device and Its Applications

    International Nuclear Information System (INIS)

    Pavcnik, Dusan; Uchida, Barry; Timmermans, Hans; Keller, Frederick S.; Roesch, Josef

    2001-01-01

    The square stent is a new, simply constructed, self-expanding device that has recently been described. Compared with other stents, the square stent has a minimal amount of metal and thus requires a smaller-diameter catheter for introduction. Despite the small amount of metal present, the square stent has adequate expansile force. We have been evaluating the square stent for various interventional applications. In addition to the basic square stent, combinations of square stents and coverings for square stents were developed and evaluated to expand its uses and indications. One of the coverings tested is a new biomaterial: small intestinal submucosa (SIS). This paper will discuss the various applications of the square stent, which include a retrievable inferior vena cava filter, vascular occluder, graft adapter, and venous and aortic valves. In addition, we will review the important properties of SIS as a covering for the square stent

  5. Differences in Endothelial Injury After Balloon Angioplasty, Insertion of Balloon-Expanded Stents or Release of Self-Expanding Stents: An Electron Microscopic Experimental Study

    International Nuclear Information System (INIS)

    Harnek, Jan; Zoucas, Evita; Carlemalm, Erik; Cwikiel, Wojciech

    1999-01-01

    Purpose: To evaluate which of six different commonly available stents inserted into an artery without percutaneous transluminal angioplasty (PTA) causes the least endothelial damage. To compare the degree of endothelial injury after insertion of such a stent with injury caused by PTA. Methods: Twelve healthy pigs were used in the experiments. In the first part of the study six different types of stents were inserted into the common iliac arteries. In the second part of the study self-expanding stents with large spaces between the wires were used. PTA was performed in the contralateral iliac artery. The pigs were killed immediately after the procedure and resected specimens examined after fixation, using scanning electron microscopy. Results: All procedures but two were accomplished successfully. More endothelium was preserved after insertion of self-expanding stents with large spaces between the wires, compared with stents with small spaces and balloon-expanded stents. After insertion of self-expanding stents with large spaces, 50.1% ± 16.4% of the endothelium remained intact, compared with only 5.6% ± 7.7% after PTA. The difference was statistically significant (p < 0.001). Conclusion: Self-expanding stents with large spaces between the wires, inserted without PTA, cause less damage to the endothelium than other stents and significantly less damage than PTA

  6. Self-expanding intracoronary stents in the treatment of coronary artery disease: new developments and future directions

    NARCIS (Netherlands)

    Lu, H.; Grundeken, M. J.; Koch, K. T.; Wykrzykowska, J. J.

    2013-01-01

    The first stent implanted in the human coronary circulation was a self-expandable (SE) stent and was introduced almost simultaneously with the first balloon-expandable (BE) stents in the late 1980s. Nowadays, the majority of the available stents are delivered by balloon expansion. While BE stents

  7. Evaluation of the Effects of Temporary Covered Nitinol Stent Placement in the Prostatic Urethra: Short-Term Study in the Canine Model

    International Nuclear Information System (INIS)

    Crisostomo, Veronica; Song, Ho Young; Maynar, Manuel; Sun, Fei; Soria, Federico; Lima, Juan Rafael; Yoon, Chang Jin; Uson-Gargallo, Jesus

    2007-01-01

    Purpose. To evaluate the effect of temporary stent placement on the canine prostatic urethra. Methods. Retrievable PTFE-covered nitinol stents were placed in the prostatic urethras of 8 beagle dogs under fluoroscopic guidance. Retrograde urethrography was obtained before and after stenting. Retrograde urethrography and endoscopy were performed 1 and 2 months after deployment. The endoscopic degree of hyperplasia was rated on a scale of 0 to 4 (0 absence, 4 = occlusion). On day 60, stents were removed and urethrography was performed immediately before euthanasia. Pathologic analysis was performed to determine the degree of glandular atrophy, periurethral fibrosis, and urethral dilation. Results. Stent deployment was technically successful in 7 animals, and failed in 1 dog due to a narrow urethral lumen. Complete migration was seen in 2 animals at 1 month, and an additional stent was deployed. On day 30, endoscopy showed slight hyperplasia (grade 1) in 3 animals. On day 60, moderate hyperplasia (grade 2) was evidenced in 4 cases. No impairment of urinary flow was seen during follow-up. Retrieval was technically easy to perform, and was successful in all dogs. The major histologic findings were chronic inflammatory cell infiltrates; prostate glandular atrophy, with a mean value of 1.86 (SD 0.90); periurethral fibrosis, with a mean ratio of 29.37 (SD 10.41); and dilatation of the prostatic urethra, with a mean ratio of 6.75 (SD 3.22). Conclusion. Temporary prostatic stent placement in dogs is safe and feasible, causing marked enlargement of the prostatic urethral lumen. Retrievable covered stents may therefore be an option for bladder outlet obstruction management in men

  8. Treatment of Benign and Malignant Tracheobronchial Obstruction with Metal Wire Stents: Experience with a Balloon-Expandable and a Self-Expandable Stent Type

    International Nuclear Information System (INIS)

    Rieger, Johannes; Hautmann, Hubert; Linsenmaier, Ulrich; Weber, Cristoph; Treitl, Markus; Huber, R.M.; Pfeifer, Klaus-Juergen

    2004-01-01

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

  9. Use of a New Hybrid Heparin-Bonded Nitinol Ring Stent in the Popliteal Artery: Procedural and Mid-term Clinical and Anatomical Outcomes

    International Nuclear Information System (INIS)

    Parthipun, Aneeta; Diamantopoulos, Athanasios; Kitrou, Panagiotis; Padayachee, Soundrie; Karunanithy, Narayan; Ahmed, Irfan; Zayed, Hany; Katsanos, Konstantinos

    2015-01-01

    PurposeTo report the immediate and mid-term clinical and anatomical outcomes of a novel, hybrid, heparin-bonded, nitinol ring stent (TIGRIS; Gore Medical) when used for the treatment of lesions located in the popliteal artery.Materials and MethodsThis was a prospective single-centre registry. Patients eligible for inclusion were individuals suffering from symptomatic popliteal arterial occlusive disease (Rutherford–Becker stage 3–6; P1–P3 segments) and treated with placement of the TIGRIS stent(s). Patients were prospectively scheduled for clinical review and duplex ultrasound follow-up after 6 and 12 months. Outcome measures included immediate technical success, primary vessel patency, in-stent binary restenosis (evaluable by Duplex at 50 % threshold; PSVR > 2.0), freedom from target lesion revascularization (TLR) and amputation-free survival (AFS) estimated by Kaplan–Meier (K–M) survival analysis. Cox proportional-hazards regression analysis was also performed to adjust for confounders and search for independent predictors of outcomes.ResultsFrom August 2012 to March 2014, a total of 54 popliteal TIGRIS stents were implanted in 50 limbs of 48 patients (27 men and 21 women; mean age 76.0 ± 1.7 years). Median Rutherford–Becker stage was five at baseline and 37/50 (74.0 %) were chronic total occlusions. Technical success was achieved in all cases (100 %). Stented lesion length was 114.2 ± 36.9 mm (range 6–20 cm). Median follow-up was 11.8 ± 0.8 months. After 12 months, primary patency of the TIGRIS stent was 69.5 ± 10.2 % with an 86.1 ± 5.9 % freedom from TLR and 87 ± 5.0 % AFS (K–M estimates).ConclusionThe TIGRIS hybrid heparin-bonded nitinol ring stent is a safe and effective endovascular option for complex occlusive disease of the popliteal artery

  10. Use of a New Hybrid Heparin-Bonded Nitinol Ring Stent in the Popliteal Artery: Procedural and Mid-term Clinical and Anatomical Outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Parthipun, Aneeta; Diamantopoulos, Athanasios; Kitrou, Panagiotis [King’s Health Partners, Department of Interventional Radiology, Guy’s and St. Thomas’ Hospitals, NHS Foundation Trust (United Kingdom); Padayachee, Soundrie [King’s Health Partners, Department of Ultrasonic Angiology, Guy’s and St. Thomas’ Hospitals, NHS Foundation Trust (United Kingdom); Karunanithy, Narayan; Ahmed, Irfan [King’s Health Partners, Department of Interventional Radiology, Guy’s and St. Thomas’ Hospitals, NHS Foundation Trust (United Kingdom); Zayed, Hany [King’s Health Partners, Department of Vascular Surgery, Guy’s and St. Thomas’ Hospitals, NHS Foundation Trust (United Kingdom); Katsanos, Konstantinos, E-mail: konstantinos.katsanos@gstt.nhs.uk, E-mail: katsanos@med.upatras.gr [King’s Health Partners, Department of Interventional Radiology, Guy’s and St. Thomas’ Hospitals, NHS Foundation Trust (United Kingdom)

    2015-08-15

    PurposeTo report the immediate and mid-term clinical and anatomical outcomes of a novel, hybrid, heparin-bonded, nitinol ring stent (TIGRIS; Gore Medical) when used for the treatment of lesions located in the popliteal artery.Materials and MethodsThis was a prospective single-centre registry. Patients eligible for inclusion were individuals suffering from symptomatic popliteal arterial occlusive disease (Rutherford–Becker stage 3–6; P1–P3 segments) and treated with placement of the TIGRIS stent(s). Patients were prospectively scheduled for clinical review and duplex ultrasound follow-up after 6 and 12 months. Outcome measures included immediate technical success, primary vessel patency, in-stent binary restenosis (evaluable by Duplex at 50 % threshold; PSVR > 2.0), freedom from target lesion revascularization (TLR) and amputation-free survival (AFS) estimated by Kaplan–Meier (K–M) survival analysis. Cox proportional-hazards regression analysis was also performed to adjust for confounders and search for independent predictors of outcomes.ResultsFrom August 2012 to March 2014, a total of 54 popliteal TIGRIS stents were implanted in 50 limbs of 48 patients (27 men and 21 women; mean age 76.0 ± 1.7 years). Median Rutherford–Becker stage was five at baseline and 37/50 (74.0 %) were chronic total occlusions. Technical success was achieved in all cases (100 %). Stented lesion length was 114.2 ± 36.9 mm (range 6–20 cm). Median follow-up was 11.8 ± 0.8 months. After 12 months, primary patency of the TIGRIS stent was 69.5 ± 10.2 % with an 86.1 ± 5.9 % freedom from TLR and 87 ± 5.0 % AFS (K–M estimates).ConclusionThe TIGRIS hybrid heparin-bonded nitinol ring stent is a safe and effective endovascular option for complex occlusive disease of the popliteal artery.

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

    Science.gov (United States)

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

    2012-02-29

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

  12. Indications for stenting during thrombolysis

    DEFF Research Database (Denmark)

    Bækgaard, N; Broholm, R; Just, Sven Richardt Lundgren

    2013-01-01

    of a stent in this position is the treatment of choice facilitating the venous flow into an unobstructed outflow tract either from the femoral vein or the deep femoral vein or both. The stent, made of stainless steel or nitinol, has to be self-expandable and flexible with radial force to overcome...... the challenges in this low-pressure system. The characteristics of the anatomy with external compression and often a curved vein segment with diameter difference make stent placement necessary. Ballooning alone has no place in this area. The proportion of inserted stents varies in the published materials...

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

    Science.gov (United States)

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

    2016-08-14

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

  14. Response of Balloon-Expandable Endoprosthetic Metallic Stents Subjected to Over-Expansion In Vitro

    International Nuclear Information System (INIS)

    Montague, B. J.; Kakimoto, W. M.; Arepally, A.; Razavi, M.; Dake, M. D.; Hofmann, L. V.

    2004-01-01

    We attempted to evaluate the in vitro behavior and performance of balloon-expandable endoprosthetic metallic stents subjected to over-expansion (OE). Seventy-two balloon-expandable endoprosthetic stents, representing 22 models from six manufacturers, were over- expanded in vitro. Stents were initially expanded to their maximum manufacturer- recommended diameter and then over-expanded incrementally to their endpoints. Endpoints for OE were either stent disarticulation or an inability to undergo further expansion despite balloon insufflation to maximum burst pressure. Measurements of stent dimensions were recorded at each overexpanded diameter and comparisons were made to manufacturer's specifications. A total of 288 balloon-driven expansions were performed on 72 stents. Sixteen stents were expanded to large diameters (≥ 16 mm), 20 stents underwent OE of 50% or greater. One model tended to disarticulate after OE greater than 50%. There were five models that had a tendency to disarticulate after minimal OE. Five models were resistant to OE (25% or less OE) but did not disarticulate. Nearly all stents showed some degree of foreshortening with OE, while 36 stents underwent foreshortening of 30% or more. Models that are not recommended for OE include Intrastent, Intrastent DoubleStrut, NIR Royale and Omniflex. Good candidates for OE include Intrastent DoubleStrut LD, Palmaz large, Medtronic Extra Support Biliary Plus and Medtronic Flexible Biliary. Palmaz XL remains the only model available for expansion from 20 to 28 mm in diameter. For the remaining stents, OE is possible, however, caution should be used

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

    DEFF Research Database (Denmark)

    Meisner, Søren; González-Huix, Ferran; Vandervoort, Jo G

    2011-01-01

    The self-expandable metal stent (SEMS) can alleviate malignant colonic obstruction and avoid emergency decompressive surgery.......The self-expandable metal stent (SEMS) can alleviate malignant colonic obstruction and avoid emergency decompressive surgery....

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

    Science.gov (United States)

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

    2016-05-01

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

  17. Expandable metal stents for tracheal obstruction: permanent or temporary? A cautionary tale.

    OpenAIRE

    Hind, C R; Donnelly, R J

    1992-01-01

    An expandable metal stent inserted via a long term tracheostomy successfully relieved life threatening respiratory obstruction due to benign tracheal stenosis. Later the patient's tracheostomy suction catheter became stuck on the stent and dislodged it. The stent was removed electively, without damaging the trachea, with a rigid biopsy forceps.

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

    Science.gov (United States)

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

    2015-02-07

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

  19. Expandable esophageal metallic stents coating with silicone rubber: An experimental study in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Han, Young Min; Son, Myung Hee; Kim, Jong Soo; Choi, Ki Chul; Kuh, Ja Hong; Chae, Soo Wan [Chonbuk National University Medical School, Chonju (Korea, Republic of); Kim, Hak Nam [Chungju Lee Rha Hospital, Chungju (Korea, Republic of)

    1990-10-15

    To determine the effect of the expandable esophageal metallic stents on the esophagus, we constructed an expandable metallic stent. It was stainless steel wire formed in a zig-zag pattern in fully expanded diameter. Twenty stents were introduced in the normal esophagus through a 8.5 French-teflon sheath in 10 rabbits for 1 week to 12 weeks. Three out of the 20 stents migrated slightly. At 1 week after the placement of the stent, the mucosa partly revealed pressure necrosis and some regeneration, the muscle layer below the stent wires found compressed and thinned. At 8 weeks, the mucosa showed complete regeneration, and the stent wires were found covered by fibrous tissue.

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

    Science.gov (United States)

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

    1999-02-01

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

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

    Science.gov (United States)

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

    2014-01-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

    Temporary placement of self-expandable stents has been increasingly used for the management of benign esophageal diseases. To evaluate the safety of endoscopic removal of esophageal self-expandable stents placed for the treatment of benign esophageal diseases. Multicenter retrospective study. Six

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

    Science.gov (United States)

    Madden, Brendan P; Sheth, Abhijat

    2005-09-01

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

  4. Medical uses of nitinol

    Energy Technology Data Exchange (ETDEWEB)

    Pelton, A.R.; Stoeckel, D.; Duering, T.W. [Nitinol Devices and Components - Cordis Corp., Fremont, CA (United States)

    2000-07-01

    The growth of nitinol in the medical industries has exploded in the past ten years. Patients and care providers have encouraged the transition from traditional open-surgical procedures, which require long hospital stays, to less-invasive techniques, which are often performed in out-patient clinics. This demand for minimally invasive procedures has allowed novel instrumentation and implants to be designed. An increasing number of these devices use nitinol as the critical component. Examples of medical applications range from orthodontic archwires and endoscopic instruments to endovascular stents. This paper will focus on key performance attributes of nitinol that make it an ideal material for medical applications. Specific applications will be introduced through their use of the enabling features. (orig.)

  5. Comparison of expandable endotracheal stents in the treatment of surgically induced piglet tracheomalacia.

    Science.gov (United States)

    Mair, E A; Parsons, D S; Lally, K P; Van Dellen, A F

    1991-09-01

    Present surgical alternatives for pediatric tracheobronchomalacia are limited and associated with many potentially undesirable complications. The feasibility of different intraluminal expandable endotracheal stents for the treatment of surgically induced tracheomalacia was analyzed in 27 piglets. A potentially fatal tracheomalacia was surgically created. Either a stainless steel "zig-zag" stent or a woven polymeric stent was then implanted. Tracheal patency, mucosal function, histopathologic respiratory tract changes, and effects of the stent on esophageal motility were evaluated over a 16-week period. Piglets with steel stents uniformly experienced intense inflammation leading to tracheal dysfunction and death. Piglets with polymeric stents experienced minimal respiratory symptoms. Expandable polymeric endotracheal stents alleviate surgically induced piglet tracheomalacia, were easy to insert, allowed for tracheal growth, and reduced the need for high-risk surgical procedures with prolonged ventilatory support.

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

    Science.gov (United States)

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

    1995-07-01

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

  7. Application of a novel retrievable self-expanding stent in intracranial aneurysm treatment

    International Nuclear Information System (INIS)

    Yang Zhigang; Liu Jianmin; Xu Yi; Huang Qinghai; Hong Bo; Zhao Wenyuan; Zhao Rui

    2008-01-01

    Objective: To assess the value of a novel retrievable self-expanding stent system (LEO) in intracranial aneurysm treatment. Methods: 43 patients with 44 intracranial aneurysms treated with LEO stent were retrospectively analized, including 16 aneurysms with single-stent deployment, 25 with stent-assisted technique, 2 with double-stent deployment and one with double-stent assisted coils. Follow up was carried out through imaging and clinical course. Results: The stent was easy for repositioning and all the stents were delivered successfully, except 1 stent with unsatisfactory position, 1 with acute in-stent thrombosis. During follow up, 1 case showed chronic in-stent thrombus and one with intimal hyperplasia. 22 aneurysms got compact coiled during procedure. Among 29 follow up cases, 72.4% aneurysms were cured or improved, 13.8% were stable and three dissection aneurysms enlarged within short period and two patients died. Conclusion: The new retrievable self-expanding stent (LEO), with the advantages of controlled delivery, easy deployment and choice for various types is a valuable system for vascular reconstruction of intracranial aneurysm with thrombosis. (authors)

  8. Understanding the requirements of self-expandable stents for heart valve replacement: Radial force, hoop force and equilibrium.

    Science.gov (United States)

    Cabrera, María Sol; Oomens, Cees W J; Baaijens, Frank P T

    2017-04-01

    A proper interpretation of the forces developed during stent crimping and deployment is of paramount importance for a better understanding of the requirements for successful heart valve replacement. The present study combines experimental and computational methods to assess the performance of a nitinol stent for tissue-engineered heart valve implantation. To validate the stent model, the mechanical response to parallel plate compression and radial crimping was evaluated experimentally. Finite element simulations showed good agreement with the experimental findings. The computational models were further used to determine the hoop force on the stent and radial force on a rigid tool during crimping and self-expansion. In addition, stent deployment against ovine and human pulmonary arteries was simulated to determine the hoop force on the stent-artery system and the equilibrium diameter for different degrees of oversizing. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Tracheal Penetration and Tracheoesophageal Fistula Caused by an Esophageal Self-Expanding Metallic Stent

    Directory of Open Access Journals (Sweden)

    Karan Madan

    2014-01-01

    Full Text Available Tracheal penetration of esophageal self-expanding metallic stents (SEMS with/without tracheoesophageal fistula (TEF formation is a rare occurrence. We report the case of a 66-year-old female patient with advanced esophageal squamous cell carcinoma who had undergone palliative esophageal stenting on three occasions for recurrent esophageal stent obstruction. On evaluation of symptoms of breathing difficulty and aspiration following third esophageal stent placement, tracheal erosion and TEF formation due to the tracheal penetration by esophageal stent were diagnosed. The patient was successfully managed by covered tracheal SEMS placement under flexible bronchoscopy.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2013-04-01

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

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

    Directory of Open Access Journals (Sweden)

    Ahmed Abdel Samie

    2012-01-01

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

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

    Science.gov (United States)

    Abdel Samie, Ahmed; Theilmann, Lorenz

    2012-01-01

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

  14. Self-Expandable Stenting over a Stent Graft for the Exclusion of a Carotid Stump: Troubleshooting for Device Incompatibility

    International Nuclear Information System (INIS)

    Youn, Sung Won; Kim, Ho Kyun; Do, Jin Kook; Kim, Young Whan

    2011-01-01

    Carotid stump, the blind remnant of an occluded internal carotid artery, can be a potential source of microemboli, and warrants its exclusion from the vascular lumen to prevent the recurrence of a microembolism. In a 69-year-old male with a symptomatic carotid stump and acute angle between left common carotid artery and aortic arch, a 7-Fr. shuttle sheath was scarcely placed into the left carotid artery but the 7-mm-diameter stent-graft-loading balloon could not be inserted into the 7-Fr. shuttle sheath. With the mounting a stent graft over a 5-mm balloon, the balloon-expandable stent graft was unfolded. The self-expandable stent was placed over the stent graft, and an 8-mm balloon was subsequently expanded. Self-expanding stenting can be useful for troubleshooting in a case of device incompatibility coming from the different calibers of the external and common carotid arteries for the successful exclusion of a symptomatic carotid stump.

  15. Self-Expandable Stenting over a Stent Graft for the Exclusion of a Carotid Stump: Troubleshooting for Device Incompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Youn, Sung Won; Kim, Ho Kyun [Dept. of Radiology, Catholic University of Daegu School of Medicine, Daegu (Korea, Republic of); Do, Jin Kook [Dept. of Neurology, Catholic University of Daegu School of Medicine, Daegu (Korea, Republic of); Kim, Young Whan [Dept. of Radiology, University College of Medicine, Daegu (Korea, Republic of)

    2011-12-15

    Carotid stump, the blind remnant of an occluded internal carotid artery, can be a potential source of microemboli, and warrants its exclusion from the vascular lumen to prevent the recurrence of a microembolism. In a 69-year-old male with a symptomatic carotid stump and acute angle between left common carotid artery and aortic arch, a 7-Fr. shuttle sheath was scarcely placed into the left carotid artery but the 7-mm-diameter stent-graft-loading balloon could not be inserted into the 7-Fr. shuttle sheath. With the mounting a stent graft over a 5-mm balloon, the balloon-expandable stent graft was unfolded. The self-expandable stent was placed over the stent graft, and an 8-mm balloon was subsequently expanded. Self-expanding stenting can be useful for troubleshooting in a case of device incompatibility coming from the different calibers of the external and common carotid arteries for the successful exclusion of a symptomatic carotid stump.

  16. Percutaneous transhepatic self-expanding metal stents for palliation ...

    African Journals Online (AJOL)

    Stent occlusion occurred in 4 patients (8%) within a week as result of stent migration (n=3) or presumed biliary sludge (n=1); 2 (4%) stents occluded between 7 days and 1 month. Four patients (8%) died during hospital admission due to pre-existing biliary sepsis (n=3) and pneumonia (n=1). Nine patients developed ...

  17. Mechanical Behavior of Fully Expanded Commercially Available Endovascular Coronary Stents

    OpenAIRE

    Tambaca, Josip; Canic, Suncica; Kosor, Mate; Fish, R. David; Paniagua, David

    2011-01-01

    The mechanical behavior of endovascular coronary stents influences their therapeutic efficacy. Through computational studies, researchers can analyze device performance and improve designs. We developed a 1-dimensional finite element method, net-based algorithm and used it to analyze the effects of radial loading and bending in commercially available stents. Our computational study included designs modeled on the Express, Cypher, Xience, and Palmaz stents.

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

    Science.gov (United States)

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

    2016-11-01

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

  19. A novel self-expanding fully retrievable intracranial stent (SOLO): experience in nine procedures of stent-assisted aneurysm coil occlusion

    International Nuclear Information System (INIS)

    Liebig, Thomas; Henkes, Hans; Reinartz, Joerg; Miloslavski, Elina; Kuehne, Dietmar

    2006-01-01

    The endovascular treatment of large and broad-necked aneurysms may require the use of a remodelling balloon or a stent system to achieve proper occlusion while maintaining the patency of the parent vessel. With the advent of self-expanding stents that can be delivered through a microcatheter, this kind of treatment has improved and problems with the previously used balloon expandable stents have largely been overcome. However, rigidity, insufficient trackability, and limited or non-existent retrievability may still restrict the application of self-expanding stents in some situations. Recently, a stent system with a new and different design has been introduced. This stent is highly flexible, fully retrievable, and can be delivered through a standard 0.021-inch microcatheter without a wire. We describe the first nine cases of stent-assisted coil occlusion of intracranial aneurysms with the use of this stent system. Between May and June of 2004, nine patients with large or broad-necked aneurysms were treated in two endovascular centres. The anatomy of the aneurysms and parent vessels, technical details of the procedure, performance of the stent system, and follow-up results were evaluated. In all procedures, the SOLO stent could be introduced without difficulty, in one procedure after positioning of a different self-expanding stent system had failed due to vessel tortuosity. Overlapping stents were placed in one patient and stent retrieval or repositioning was successfully performed in two procedures. There was no interference or limitation of subsequent coil occlusion after stenting. With regard to the stent, immediate postprocedure and follow-up angiograms were unremarkable in terms of thromboembolic events and signs of intimal hyperplasia. From our experience, we conclude that the SOLO stent shows satisfactory performance overall. Its unique design gives the stent properties that may help overcome some of the difficulties experienced with other self-expanding

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

    Science.gov (United States)

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

    2013-10-01

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

  1. [Evaluation of stents in treating childhood benign esophageal strictures].

    Science.gov (United States)

    Reinshagen, K; Kähler, G; Manegold, B C; Waag, K-L

    2009-01-01

    Esophageal stenting is a popular of treatment of esophageal strictures in adults. It has also been described for children with benign strictures who did not respond to standard dilatation therapy. The aim of the study was to evaluate weather esophageal stents could be used safely and effectively in the treatment of benign esophageal strictures in children. From 1993 to 2005 stenting therapy was performed in 12 children with complicated esophageal strictures. Etiologies of the strictures were caustic burns in 9 patients, postoperative strictures due to complicated esophageal atresia in 2 patients and iatrogenic esophageal injury in 1 patient. Esophageal silicon tubi, covered retrievable expandable nitinol and plastic stents were placed endoscopically. The clinical course and the long term follow up were evaluated retrospectively The stents and tubi were placed in all patients without complications and were later removed successfully. 6 patients were treated with a self expanding plastic stent. The plastic stents showed a distinct tendency to migrate but in 5/6 patients esophageal stricture was treated successfully. 3 patients were treated by a covered self expanding nitinol stent. No migration occurred. One patient was asymptomatic after therapy, one required further dilatation therapy and the third had esophageal resection. 3 patients were treated by esophageal tubi. 2 patients required surgery in the follow up, one patient is asymptomatic. The use of stenting devices in children to treat benign esophageal strictures is safe and efficient. The self expanding plastic stents had the best long term results but required high compliance of parents and children due to the tendency of stent migration. Self expanding nitinol stents are more traumatic at the extraction procedure and are useful in patients with low compliance. Recurrence of strictures occurred most often after esophageal tubi possibly due to the lack of radial expansion.

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

    Science.gov (United States)

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

    2017-09-14

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

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

    Science.gov (United States)

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

    2013-03-01

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

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

    Science.gov (United States)

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

    2015-08-14

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

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

    Science.gov (United States)

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

    2013-01-01

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

  6. Removal of self expandable metallic airway stent: A rare case report

    Directory of Open Access Journals (Sweden)

    Rakesh K Chawla

    2013-01-01

    Full Text Available Covered self expandable metallic airway stents (SEMS have been used for benign tracheal stenosis, post intubation tracheal stenosis, tracheal burn or trauma, tracheo-broncho-malacia, and extrinsic compression of trachea. Their placement is considered to be permanent, with open surgery the only way to remove the stent, though there are few cases reports of their removal with the bronchoscope, but the complications after their removal are very high. In our patient, one and a half years after placement of SEMS, she developed cough with dyspnoea, video bronchoscopy showed stenosis above the level of stent with granulation tissue inside the stent, stent fracture in lower part and stent migration to right main bronchus, thus she had all conceivable complications of stent placement. The stent was removed with the help of rigid bronchoscope under general anaesthesia. She was discharged the following day. The case is being reported because it was unique in having all the possible complications of stent placement, and rare as we could take out the stent in Toto. Thirdly, the stent could be removed without any complication.

  7. Self-expanding metal stents in benign biliary strictures due to chronic pancreatitis

    NARCIS (Netherlands)

    van Berkel, A. M.; Cahen, D. L.; van Westerloo, D. J.; Rauws, E. A.; Huibregtse, K.; Bruno, M. J.

    2004-01-01

    Background and Study Aims: In selected patients with chronic pancreatitis in whom conventional plastic stenting fails and in whom surgery is contraindicated or declined, insertion of a biliary self-expanding metal stent (SEMS) may be a valuable treatment option. Patients and Methods: Between 1994

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

    Science.gov (United States)

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

    2015-07-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

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

    Science.gov (United States)

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

    2018-01-01

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

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

    Science.gov (United States)

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

    2015-06-01

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

  12. Utility of MR cholangiography for follow-up examination after metallic stent placement in the bile duct

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chul Hi; Yang, Dal Mo; Kim Hak Soo; Cho, Seung Whi; Kim, Hyung Sik; Jin Wook; Hwang, Hee Young [Gachon Medical College Gil Medical Center, Incheon (Korea, Republic of)

    2002-09-01

    To evaluate the efficacy of MR cholangiography for follow-up examination after metallic stent placement in the bile duct. Between December 1999 and June 2000, 15 patients with biliary obstruction in whom metallic biliary stents had been placed underwent MR cholangiography during follow-up examination. The causes of obstruction were hilar cholangiocarcinoma (n=6), common bile duct cancer (n=5), gall bladder cancer (n=1) and pancreatic cancer (m=3). The types of self-expandable metallic stent employed were the nitinol stent (n=2), the endocoil nitinol stent (n=3), the ultraflexed diamond stent (n=5), and the wallstent (n=5). Using MR cholangiography, we measured the diameter of that part of the biliary stent which showed high signal intensity, assigning one point if this was less than one third of the stent diameter, two points of between one third and two thirds, and three points if more than two thirds. We decided that a higher score indicated fewer artifacts. The score was 1.7-3 (mean, 2.3) points for the endocoil nitinol stent, 1.7-2.3 (mean, 2) for the nitinol stent, and 1-3 (mean, 1.7) for the ultraflex diamond stent. In most cases, two thirds of the stent diameter was observed. For the wallstent, the score was 1-1.7 (mean, 1.3) points and the inner portion of the stent was almost invisible. MR cholangiography is not useful for follow-up examination after the placement of wallstents and three other types of nitinol stent in the bile duct.

  13. Circumferential and fusiform intracranial aneurysms: reconstructive endovascular treatment with self-expandable stents

    Energy Technology Data Exchange (ETDEWEB)

    Lubicz, Boris [Erasme University Hospital, Department of Neuroradiology, Brussels (Belgium); Hopital Erasme, Service de Radiologie (EA 2691), Brussels (Belgium); Collignon, Laurent; Baleriaux, Danielle [Erasme University Hospital, Department of Neuroradiology, Brussels (Belgium); Lefranc, Florence; Bruneau, Michael; Brotchi, Jacques; Witte, Olivier de [Erasme University Hospital, Department of Neurosurgery, Brussels (Belgium)

    2008-06-15

    We report our experience with endovascular treatment (EVT) of circumferential and fusiform intracranial aneurysms by a reconstructive approach with self-expandable stents. A retrospective review of our prospectively maintained database identified all circumferential and fusiform aneurysms treated by a reconstructive endovascular approach over a 3-year period. Clinical charts, procedural data, and angiographic results were reviewed. From April 2004 to May 2007, 13 patients were identified, of whom 12 were asymptomatic and 1 presented with a subarachnoid hemorrhage. Two patients with an aneurysm {<=}2 mm were treated by stent-within-stent placement without coiling (group 1). In 11 patients with a larger aneurysm, stenting with subsequent coiling was performed (group 2). In this latter approach, a balloon was temporarily inflated within the stent to ensure safe coil delivery. All patients showed an excellent clinical outcome. Asymptomatic procedural complications occurred in three patients, two with cervical internal carotid artery dissection and one with retroperitoneal hematoma. In patients of group 1, the aneurysm had completely disappeared at 6 months. In patients of group 2, aneurysm occlusion was complete in three and incomplete in eight. Follow-up angiography in 12 patients showed four with further thrombosis, six with stable results, and two with minor recanalization. Circumferential and fusiform intracranial aneurysms may be treated by a reconstructive endovascular approach with self-expandable stents. In small aneurysms, a stent-within-stent technique is effective, whereas stenting and subsequent coiling is indicated in larger aneurysms. This therapeutic protocol is associated with good clinical and anatomical results. (orig.)

  14. Role of fluoroscopic guided self expandable metallic stents in the management of malignant esophageal strictures

    OpenAIRE

    Mohamed Shaker; Ahmed Deif; Amr Abdelaal

    2016-01-01

    Objectives: To evaluate the role of fluoroscopic guided self expanding metallic stents in the management of dysphagia caused by malignant esophageal strictures. Materials and methods: During the period between April 2010 and October 2012, 31 patients with malignant esophageal strictures were subjected to fluoroscopic guided self expanding metallic stent application. The study included 22 males and 9 females ranging in age between 22 and 75 years old with mean age of 56.8 years. Lesions wer...

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

    Science.gov (United States)

    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.

  16. Design and modeling balloon-expandable coronary stent for manufacturability

    Science.gov (United States)

    Suryawan, D.; Suyitno

    2017-02-01

    Coronary artery disease (CAD) is a disease that caused by narrowing of the coronary artery. The narrowing coronary artery is usually caused by cholesterol-containing deposit (plaque) which can cause a heart attack. CAD is the most common cause mortality in Indonesia. The commonly CAD treatment use the stent to opens or alleviate the narrowing coronary artery. In this study, the stent design is optimized for the manufacturability. Modeling is used to determine the free stent expansion due to applied pressure in the inner surface of the stent. The stress distribution, outer diameter change, and dogboning phenomena are investigated in the simulation. The result of modeling and simulating was analyzed and used to optimize the stent design before it is manufactured using EDM (Electric Discharge Machine) in the next research.

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

    Science.gov (United States)

    Hsiao, Hao-Ming; Yin, Ming-Ting

    2014-02-01

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

  18. Self-expanding oesophageal metal stents for the palliation of dysphagia due to extrinsic compression

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, N.K.; Boylan, C.E.; Razzaq, R.; England, R.E.; Mirra, L.; Martin, D.F. [Dept. of Radiology, South Manchester University Hospitals NHS Trust, Withington Hospital (United Kingdom)

    1999-07-01

    The role of self-expanding metallic stents is well established in the palliation of oesophageal stenosis and dysphagia due to primary oesophageal malignancy. However, their role in palliation of dysphagia due to external compressive mediastinal malignancies is not well established. The purpose of this study was to assess the efficacy of self-expanding metallic stents in the palliation of dysphagia due to extrinsic oesophageal compression by mediastinal malignancy. Between January 1995 and January 1998, 21 patients with oesophageal compression due to malignant mediastinal tumours underwent oesophageal stent placement for palliation of dysphagia. Complete data were available in 17 patients (10 men and 7 women). The mean age was 63.5 years (range 46-89 years). A total of 19 stents were placed successfully. The dysphagia grade prior to and after oesophageal stent placement was assessed and the complications documented. Of the 17 patients, 16 reported an improvement in dysphagia. The mean dysphagia score improved from 3.1 prior to treatment to 1.3 after treatment. In 1 patient the stent slipped during placement and another stent was placed satisfactorily. Early complications (within 48 h) in the form of mild to moderate retrosternal chest pain occurred in 5 patients. This was treated symptomatically. Late complications (after 48 h) in the form of bolus impaction occurred in 2 patients. This was successfully treated with oesophagoscopy and removal of bolus. In 2 patients the stent was overgrown by tumour and in one of these an additional stent was placed. In 1 patient incomplete closure of a tracheo-oesophageal fistula was observed. There was no procedure- or stent-related mortality. The mean survival time of this group was 2.1 months. Self-expanding metallic stents can be safely and effectively used in the palliation of dysphagia due to external mediastinal malignancies. (orig.)

  19. Self-expanding oesophageal metal stents for the palliation of dysphagia due to extrinsic compression

    International Nuclear Information System (INIS)

    Gupta, N.K.; Boylan, C.E.; Razzaq, R.; England, R.E.; Mirra, L.; Martin, D.F.

    1999-01-01

    The role of self-expanding metallic stents is well established in the palliation of oesophageal stenosis and dysphagia due to primary oesophageal malignancy. However, their role in palliation of dysphagia due to external compressive mediastinal malignancies is not well established. The purpose of this study was to assess the efficacy of self-expanding metallic stents in the palliation of dysphagia due to extrinsic oesophageal compression by mediastinal malignancy. Between January 1995 and January 1998, 21 patients with oesophageal compression due to malignant mediastinal tumours underwent oesophageal stent placement for palliation of dysphagia. Complete data were available in 17 patients (10 men and 7 women). The mean age was 63.5 years (range 46-89 years). A total of 19 stents were placed successfully. The dysphagia grade prior to and after oesophageal stent placement was assessed and the complications documented. Of the 17 patients, 16 reported an improvement in dysphagia. The mean dysphagia score improved from 3.1 prior to treatment to 1.3 after treatment. In 1 patient the stent slipped during placement and another stent was placed satisfactorily. Early complications (within 48 h) in the form of mild to moderate retrosternal chest pain occurred in 5 patients. This was treated symptomatically. Late complications (after 48 h) in the form of bolus impaction occurred in 2 patients. This was successfully treated with oesophagoscopy and removal of bolus. In 2 patients the stent was overgrown by tumour and in one of these an additional stent was placed. In 1 patient incomplete closure of a tracheo-oesophageal fistula was observed. There was no procedure- or stent-related mortality. The mean survival time of this group was 2.1 months. Self-expanding metallic stents can be safely and effectively used in the palliation of dysphagia due to external mediastinal malignancies. (orig.)

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

    Science.gov (United States)

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

    2017-04-01

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

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

    Science.gov (United States)

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

    2017-07-01

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

  2. Renal Transplant Ureteral Stenosis: Treatment by Self-Expanding Metallic Stent

    International Nuclear Information System (INIS)

    Cantasdemir, Murat; Kantarci, Fatih; Numan, Furuzan; Mihmanli, Ismail; Kalender, Betul

    2003-01-01

    We report the use of a metallic stent in a transplant ureteral stenosis. A 28-year-old man with chronic renal failure due to chronic pyelonephritis, who received a living-donor renal transplant, presented with transplant ureteral stenosis. The stenosis was unresponsive to balloon dilation and was treated by antegrade placement of a self-expanding Memotherm stent. The stentedureter stayed patent for 3 years. It may be reasonable to treat post-transplant ureteral stenosis resistant to balloon dilation with self-expanding metallic stents. However, long-term follow-up is required to evaluate the efficacy of this treatment

  3. Supera self-expanding stents for endovascular treatment of femoropopliteal disease: a review of the clinical evidence

    Directory of Open Access Journals (Sweden)

    Bishu K

    2015-07-01

    Full Text Available Kalkidan Bishu,1,2 Ehrin J Armstrong1,21Division of Cardiology, University of Colorado, Aurora, 2Denver VA Medical Center, Denver, CO, USAAbstract: Femoropopliteal lesions account for a significant proportion of endovascular interventions for peripheral artery disease in patients with disabling claudication or chronic limb ischemia. The femoropopliteal artery crosses two joint structures (hip and knee joints and courses through the muscular adductor canal in the thigh, which places the artery at increased biomechanical stress. There is a critical need for stent platforms with a reduced risk of stent fracture while maintaining patency during long-term follow-up. The Supera peripheral stent system has a braided nickel–titanium alloy stent designed to withstand the unique stressors along the course of the femoropopliteal artery. This design may be associated with improved patency in association with reduced stent fracture rates on short- and medium-term follow-up. Further studies, including randomized controlled studies, comparing the Supera interwoven nickel–titanium alloy stent system with other stent platforms and angioplasty alone are needed.Keywords: peripheral artery disease, femoropopliteal atherosclerosis, SUPERA interwoven nitinol stent, stent fracture

  4. Self-Expanding Metal Stenting for Palliation of Patients with Malignant Colonic Obstruction

    DEFF Research Database (Denmark)

    Meisner, Søren; González-Huix, Ferran; Vandervoort, Jo G

    2012-01-01

    Background. Self-expanding metal stents can alleviate malignant colonic obstruction in incurable patients and avoid palliative stoma surgery. Objective. Evaluate stent effectiveness and safety on palliation of patients with malignant colorectal strictures. Design. Two prospective, one Spanish....... Interventions(s). Self-expanding metal stent placement. Main Outcome Measures. Procedural success, clinical success, and safety. Results. Procedural success was 98.4% (251). Clinical success rates were 87.8% at 30 days, 89.7% at 3 months, 92.8% at 6 months, and 96% at 12 months. Overall perforation rate was 5...... for patients with malignant colonic obstruction should be self-expanding metal stent placement due to high rates of technical success and efficacy in symptom palliation and few complications....

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

    Science.gov (United States)

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

    2016-02-01

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

  6. Transnasal tracheobronchial stenting for malignant airway narrowing under local anesthesia: Our experience of treating three cases using this technique

    International Nuclear Information System (INIS)

    Medhi, Jayanta; Handique, Akash; Goyal, Amit; Lynser, Donbok; Phukan, Pranjal; Sarma, Kalyan; Padmanabhan, Aswin; Saikia, Manuj Kumar; Chutia, Happy

    2016-01-01

    To study the technical feasibility of tracheobronchial stenting via transnasal route under bronchoscopy and fluoroscopic guidance in severe malignant airway strictures using self-expandable nitinol stents. We describe three patients with malignant airway strictures, treated entirely via transnasal route under local anesthesia using bronchoscopic and fluoroscopic guidance. Nasal route allowed convenient access to the airway for the bronchoscope across the stricture and a guidewire was introduced through its working channel. The 18F tracheal stent and the 6F bronchial stent assembly could be easily introduced and deployed under bronchoscopic (reintroduced through the other nostril) and fluoroscopic guidance. We achieved technical success in all the three patients with immediate relief of dyspnea. Transnasal airway stenting with self-expandable nitinol stent using bronchoscopic and fluoroscopic guidance under local anesthesia is a safe and effective method with minimal patient discomfort

  7. Transnasal tracheobronchial stenting for malignant airway narrowing under local anesthesia: Our experience of treating three cases using this technique

    Directory of Open Access Journals (Sweden)

    Jayanta Medhi

    2016-01-01

    Full Text Available Purpose: To study the technical feasibility of tracheobronchial stenting via transnasal route under bronchoscopy and fluoroscopic guidance in severe malignant airway strictures using self-expandable nitinol stents. Materials and Methods: We describe three patients with malignant airway strictures, treated entirely via transnasal route under local anesthesia using bronchoscopic and fluoroscopic guidance. Nasal route allowed convenient access to the airway for the bronchoscope across the stricture and a guidewire was introduced through its working channel. The 18F tracheal stent and the 6F bronchial stent assembly could be easily introduced and deployed under bronchoscopic (reintroduced through the other nostril and fluoroscopic guidance. Results: We achieved technical success in all the three patients with immediate relief of dyspnea. Conclusion: Transnasal airway stenting with self-expandable nitinol stent using bronchoscopic and fluoroscopic guidance under local anesthesia is a safe and effective method with minimal patient discomfort.

  8. Complications related to conventional self-expandable metal stent insertion and internal irradiation stent insertion in patients with advanced esophageal carcinoma: an analysis of 32 cases

    International Nuclear Information System (INIS)

    Xu Xingwen; Di Haiting; Zhu Jun; Shi Jian

    2011-01-01

    Objective: To compare the occurrence of complications between conventional self-expandable metal stent and internal irradiation stent insertion in treating patients with advanced esophageal carcinomas. Methods: A total of 32 patients with advanced esophageal carcinoma were randomly divided into irradiation stent group (n=15) and conventional stent group (n=17). Internal irradiation stent loaded with 125 I seeds was employed in patients of irradiation stent group, while conventional self-expandable metal stent was used in patients of conventional stent group. After the treatment, clinical follow-up was regularly conducted. Postoperative complications such as fever, severe chest pain, cough, esophageal perforation, pneumonia, hemorrhage, stent migration and restenosis, etc. were observed. Results: No significant difference in the occurrence of fever, severe chest pain, esophageal perforation and hemorrhage existed between the two groups (P>0.05). The difference in the occurrence of long-term complications such as stent migration or restenosis between the two groups was out statistically significant (P>0.05). However, the restenosis in irradiation stent group occurred obviously much later than that in conventional stent group. Conclusion: For the treatment of advanced esophageal carcinomas, the insertion of internal irradiation esophageal stent is safe. It dose not increase the incidence of postoperative complications. Therefore, it is worth popularizing this technique in clinical practice. (authors)

  9. Expandable metallic stents: An experimental study in the nasolacrimal systems of dogs

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Lee, Jeong Min; Han, Young Min; Hwang, Eui Il; Chung, Gyung Ho; Shon, Myung Hee; Kim, Chong Soo; Choi, Ki Chul [Chonbuk National University Medical School, Chonju(Korea, Republic of)

    1993-11-15

    Balloon dacryocystoplasty has been reported to be a safe, easy and effective nonoperative treatment for nasolacrimal stenosis. The results were not encouraging, however, because of its high failure and recurrence rates. To evaluate the feasibility of using modified Gianturco expandable metallic stents for maintenance of the dilated nasolacrimal system(NLS), 20 stents of 3 mm in diameter and 10 mm long were placed in 20 nasolacrimal ducts of 10 dogs for 1 month to 10 months. It was more difficult to introduce the stents into the proximal portion(A) of the NLS than into the distal portion(B) due to the narrow and bony canal of the A portion. Twenty stents showed no migration in follow-up studies of up to 10 months. One complete occlusion occurred in a stent placed in A portion. Autopsy studies showed stents were covered with epithelium within 2 months after placement. Our experience suggest that the placement of Gianturco self-expandable stents may be a useful method of dilating and maintaining the luminal diameter of the NLS, although care must be taken to select the proper stent size.

  10. Expandable metallic stents: An experimental study in the nasolacrimal systems of dogs

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Jeong Min; Han, Young Min; Hwang, Eui Il; Chung, Gyung Ho; Shon, Myung Hee; Kim, Chong Soo; Choi, Ki Chul

    1993-01-01

    Balloon dacryocystoplasty has been reported to be a safe, easy and effective nonoperative treatment for nasolacrimal stenosis. The results were not encouraging, however, because of its high failure and recurrence rates. To evaluate the feasibility of using modified Gianturco expandable metallic stents for maintenance of the dilated nasolacrimal system(NLS), 20 stents of 3 mm in diameter and 10 mm long were placed in 20 nasolacrimal ducts of 10 dogs for 1 month to 10 months. It was more difficult to introduce the stents into the proximal portion(A) of the NLS than into the distal portion(B) due to the narrow and bony canal of the A portion. Twenty stents showed no migration in follow-up studies of up to 10 months. One complete occlusion occurred in a stent placed in A portion. Autopsy studies showed stents were covered with epithelium within 2 months after placement. Our experience suggest that the placement of Gianturco self-expandable stents may be a useful method of dilating and maintaining the luminal diameter of the NLS, although care must be taken to select the proper stent size

  11. Long-term results of percutaneous self-expandable metallic stents in malignant biliary obstruction

    International Nuclear Information System (INIS)

    Kobashi, Yuko; Hoshikawa, Yoshikazu

    2004-01-01

    Evaluation of the long-term follow-up data of 155 patients with inoperable malignant biliary obstruction who received percutaneous placement of self expandable metallic stent (EMS) and external beam radiotherapy (EBR) combined with self-expandable metallic stent. One-hundred sixty EMS were inserted in 155 patients with inoperable malignant biliary obstruction. One-hundred forty-three patients (Group A) were inserted EMS alone. Twelve patients (Group B) underwent external radiotherapy (40∼45 Gy) after stent insertion. We compared to the Group A and Group B about survival, stent patency and administration. The mean length of survival for the entire group was 111±87 days, while the mean period of patency for all stents was 103±74. We found no statistically significant difference in patient survival or stent patency periods in regard to the level and cause of obstruction. Prolongation of actuarial survival was observed in Group B (316±231 days) as compared to Group A (126±85 days,). Mean length of survival rate and mean period of stent patency rate were not significantly different in regard to the level, cause of obstruction and each stent. External radiotherapy combined EMS could achieve effective palliation and improve the quality of life in selected patients with malignant biliary obstruction. (author)

  12. Physical property and MR imaging of self-expandable metallic stents

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Hong Gee; Kang, Sung Gwon; Cho, Young Kook; Kim, Hyung Jin; Lim, Myung Kwan; Cho, Soon Gu; Yoh, Kyu Tong; Suh, Chang Hae [Inha Univ., College of Medicine, Seoul (Korea, Republic of)

    1998-09-01

    In order to furnish basic information prior to their use, the physical properties of various self-expandable metallic stents and their MR characteristics were evaluated. Four commercially available self-expandable metallic stents-Gianturco-the Rosch, Hanaro, Memotherm, and Wallstent-were used in this study. For evaluation of the physical properties of each, hoop strengths and changes in radii according to the degrees of longitudinal flexion were compared. Stent characteristics seen on MR images were evaluated by measuring magnetic torque and by comparing images obtained in the vascular phantom using SE T1TI, FSE T2WI, and FMPSPGR sequences. These images were analyzed with special emphasis on artifact size and the apparant shepe of the stent. Hoop strength was greatest in the Gianturco-Rosch stent, followed by the Memotherm, Hanaro, and Wallstent. When flexed in the longitudinal axis, the radius of the Hanaro and Memotherm stent decreased slightly as a larger flexion angle was applied. When this was 90 deg, however, the connection of the Gianturco-Rosch stent collapsed. In contrast, the radius of the Wallstent became larger as a larger flexion angle was applied. At the portal of the MR imaging unit, neither the Memotherm nor Wallstent showed deflection; except for a thin hyperintense rim at both ends, their images were excellent, and the lumina of these stents were also clearly seen. In contrast, the Gianturco-Rosch and Hanaro stent demonstrated large deflexion and showed a severe black-hole artifact. As a result, visualization of the stents themselves and their lumina was impossible. The Gianturco-Rosch stent showed greatrer hoop strength than the others. The Wallstent showed good longitudinal flexibility and was thought to be effective in tortuous vessels. For follow-up after placement, especially when the nonferromagnetic Memotherm and Wallstent are used, MR imaging appears to be safe and useful.=20.

  13. Treatment of intracranial wide neck aneurysm with neuroform self-expanding stent combined with spring coils

    International Nuclear Information System (INIS)

    Bai Weixing; Jiang Xifeng; Li Tianxiao; Zhai Shuiting; Xue Jiangyu; Wang Ziliang; Cao Huicun

    2008-01-01

    Objective: To evaluate the preliminary experience of the combined self-expanding neurovascular stent (Neuroform stent) with detachable coils in the management of intracranial wide neck aneurysms. Methods: Self-expanding neurovascular stents with detachable coils were used in treating 27 intracranial wide neck aneurysms of 25 patients including cavernous segment ICA aneurysms in 3, ophthalmic arterial anemysm in 1, PcomA in 18, AcomA in 2, MCAM1 in 1, MCA bifurcation in 1, and basilar trunk in 1. Among them, 2 cases consisted of multi-aneurysms, 2 aneurysms coincide with absolute wide neck (> 4 mm) and 6 with comparatively wide neck (> 7 mm). Nemoform stents were deployed across the neck of aneurysm and detachable coils were released to embolize the aneurysm through stent mesh. Results: Twenty-six Neuroform stents were successfully deployed in 25 patients including 4 Neuroform II stents, and 22 Neurofom III stents(all combined with spring coils). Total occlusion was achieved in 7 patients with residual neck in 9 nearly complete occlusion and partial occlusion in 11. 2 patients were rebleeding and other 2 showed intra-stent thrombosis during the operations. The latter 2 included 1 with post-operative limb paraplegia and 1 died. Still another 1 had transient ischemic attack after the operation. Twenty-three patient recovered well. Twenty-four patients were under clinical followed up from 0.5 to 28 months with an average of 10.8 months. There was no bleeding. Three patients were angiographically followed up for 3-6 months after the procedure, with only 1 case of in-stent thrombosis and no change in other 2 aneurysms with neck remnant. Conclusions: The Neuroform stent is technically feasible and safe for treating intracranial wide neck aneurysms unsuitable for clipping because of its prevention for coil protruding into parent artery. The long term effect still need to be further investigated. (authors)

  14. Self-expandable metallic stents for patients with recurrent esophageal carcinoma after failure of primary chemoradiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Muto, Manabu; Ohtsu, Atsushi; Boku, Narikazu; Yoshida, Shigeaki [National Cancer Center, Kashiwa, Chiba (Japan). Hospital East; Miyata, Yoshinori; Shioyama, Yasukazu

    2001-06-01

    Recent advances in chemoradiotherapy for esophageal carcinoma have resulted in improved survival rates. However, there are few options for recurrent dysphagia due to refractory carcinoma after failure of primary chemoradiotherapy. The aim of this study was to evaluate the safety and efficacy of self-expandable metallic stent placement for patients with recurrent esophageal carcinoma where definitive chemoradiotherapy has failed. Thirteen consecutive patients with recurrent squamous cell carcinoma of the esophagus, in whom self-expandable metallic stents were placed after failure of primary chemoradiotherapy, were studied retrospectively. All patients had esophageal obstruction or malignant fistula. The oral alimentation status of nine of 13 patients (69%) improved after successful placement of the stent. Following placement of the stent, fever (>38 deg C) and severe chest pain occurred in 85% (11/13) of the patients. In all patients examined, C-reactive protein was elevated within 1 week of the operation. Esophageal perforation occurred in three patients. Stent-related mediastinitis and pneumonia developed in six (46%) and three (23%) patients, respectively. Seven of the 13 patients (54%) died of stent-related pulmonary complications. Although the placement of a self-expandable metallic stent for patients with recurrent esophageal carcinoma after failure of chemoradiotherapy improved their oral alimentation status, we found that this treatment increases the risk of life-threatening pulmonary complications. (author)

  15. Self-expandable metallic stents for patients with recurrent esophageal carcinoma after failure of primary chemoradiotherapy

    International Nuclear Information System (INIS)

    Muto, Manabu; Ohtsu, Atsushi; Boku, Narikazu; Yoshida, Shigeaki; Miyata, Yoshinori; Shioyama, Yasukazu

    2001-01-01

    Recent advances in chemoradiotherapy for esophageal carcinoma have resulted in improved survival rates. However, there are few options for recurrent dysphagia due to refractory carcinoma after failure of primary chemoradiotherapy. The aim of this study was to evaluate the safety and efficacy of self-expandable metallic stent placement for patients with recurrent esophageal carcinoma where definitive chemoradiotherapy has failed. Thirteen consecutive patients with recurrent squamous cell carcinoma of the esophagus, in whom self-expandable metallic stents were placed after failure of primary chemoradiotherapy, were studied retrospectively. All patients had esophageal obstruction or malignant fistula. The oral alimentation status of nine of 13 patients (69%) improved after successful placement of the stent. Following placement of the stent, fever (>38 deg C) and severe chest pain occurred in 85% (11/13) of the patients. In all patients examined, C-reactive protein was elevated within 1 week of the operation. Esophageal perforation occurred in three patients. Stent-related mediastinitis and pneumonia developed in six (46%) and three (23%) patients, respectively. Seven of the 13 patients (54%) died of stent-related pulmonary complications. Although the placement of a self-expandable metallic stent for patients with recurrent esophageal carcinoma after failure of chemoradiotherapy improved their oral alimentation status, we found that this treatment increases the risk of life-threatening pulmonary complications. (author)

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

    Science.gov (United States)

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

    2011-01-01

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

  17. The use of self expandable metallic stent in the management of malignant biliary obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Han, Joon Koo; Choi, Byung Ihn; Chung, Jin Wook; Park, Jae Hyung; Han, Gi Seok; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1993-05-15

    Self expandable metallic stent is a good alternative of percutaneous transhepatic biliary drainage because it can eliminate numerous problems caused by external drainage catheter, such as tube dislodgement, bile leakage and psychotic problems. Authors analyzed initial results of self expandable metallic stents used in the patient with malignant biliary obstruction to evaluate the efficacy of the procedure and to find the technical problems in the procedure. Self expandable metallic stents were inserted in 14 patients: three with recurrent stomach cancer: three with gallbladder cancer: seven with Klaskin tumor: one with common duct cancer. Gianturco type stent was used in 9 cases ans Wallstent was used in 2 cases. In remaining three case, both Z-stent and Wallstent were used in the same patient. The average period of follow up was 104 days (4-409 days). In 13 cases, the patency of the bile duct was restored by the stent (technical success: 92.9%). Occlusions of the stent were found in two cases, after two and 13 months, respectively. Causes of failure and stent occlusion were associated duodenal obstruction, tumor overgrowth and shortening of Wallstent. In remaining 11 patients, one patient was lost to follow up an 10 patients did not show recurrent jaundice until death or last follow up. There was no major complication related to the procedure. The insertion of self expandable metallic stent is a safe procedure and can eliminate major disadvantages of PTBD. Overstenting, overlapping and evaluation of associated GI tract obstruction is crucial for obtaining technical success and long-term patency.

  18. The use of self expandable metallic stent in the management of malignant biliary obstruction

    International Nuclear Information System (INIS)

    Han, Joon Koo; Choi, Byung Ihn; Chung, Jin Wook; Park, Jae Hyung; Han, Gi Seok; Han, Man Chung

    1993-01-01

    Self expandable metallic stent is a good alternative of percutaneous transhepatic biliary drainage because it can eliminate numerous problems caused by external drainage catheter, such as tube dislodgement, bile leakage and psychotic problems. Authors analyzed initial results of self expandable metallic stents used in the patient with malignant biliary obstruction to evaluate the efficacy of the procedure and to find the technical problems in the procedure. Self expandable metallic stents were inserted in 14 patients: three with recurrent stomach cancer: three with gallbladder cancer: seven with Klaskin tumor: one with common duct cancer. Gianturco type stent was used in 9 cases ans Wallstent was used in 2 cases. In remaining three case, both Z-stent and Wallstent were used in the same patient. The average period of follow up was 104 days (4-409 days). In 13 cases, the patency of the bile duct was restored by the stent (technical success: 92.9%). Occlusions of the stent were found in two cases, after two and 13 months, respectively. Causes of failure and stent occlusion were associated duodenal obstruction, tumor overgrowth and shortening of Wallstent. In remaining 11 patients, one patient was lost to follow up an 10 patients did not show recurrent jaundice until death or last follow up. There was no major complication related to the procedure. The insertion of self expandable metallic stent is a safe procedure and can eliminate major disadvantages of PTBD. Overstenting, overlapping and evaluation of associated GI tract obstruction is crucial for obtaining technical success and long-term patency

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

    Science.gov (United States)

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

    2016-09-01

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

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

    Science.gov (United States)

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

    2013-06-01

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

  1. cancerous esophagotracheal fistula: treatment of placement with covered self-expanding metallic stent

    International Nuclear Information System (INIS)

    Han Xinwei; Li Tianxiao; Wang Ruilin; Fan Qingxia

    1997-01-01

    Purpose: To treat the esophagotracheal fistula that was the main cause of death in patients with esophageal carcinoma, the placement of the stent was studied. Materials and methods: Under the fluoroscopic guidance, 28 stents (5 stents made in USA and 23 in China) were successfully implanted in all the 28 patients with esophagotracheal fistula. Results: The aphagia of the patients was greatly improved and a normal diet could be swallowed at once after the placement of the stents. The 27 cases of inhalation pneumonia that caused by the fistula was recovered. Conclusion: The result indicated that the treatment with the placement of the covered self-expanding stent is simple, safe, and effective for most patients with aphagia and pneumonia due to esophagotracheal fistula

  2. Subclinical leaflet thickening and stent frame geometry in self-expanding transcatheter heart valves

    DEFF Research Database (Denmark)

    Fuchs, Andreas; De Backer, Ole; Brooks, Matthew

    2017-01-01

    AIMS: This study aimed to assess the potential relationship between subclinical leaflet thickening and stent frame geometry in patients who underwent aortic valve replacement with a self-expanding transcatheter heart valve (THV). METHODS AND RESULTS: Seventy-five patients with a self-expanding THV....... CONCLUSIONS: Regional THV stent frame underexpansion is associated with an increased risk of leaflet thickening. Post-dilatation of self-expanding THV as well as a supra-annular valve position seem to reduce the occurrence of this phenomenon....

  3. Hemodialysis shunts-related subclavian vein stenosis : treatment with self-expandable metallic stent

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Gyee; Lee, Young Chul; Shin, Sang Soo; Kim, Yun Hyeon; Kim, Jae Kyu; Kang, Heoung Keun; Jeong, Sang Young; Choi, Su Jin Na [Chonnam Univ. College of Medicine, Kwangju (Korea, Republic of)

    1999-04-01

    To evaluate the usefulness of placement of self-expandable stents in hemodialytic shunt-related subclavian vein stenosis. Self-expandable metallic stent was placed in nine patients with hemodialytic shunt-related subclavian vein stenosis. In seven cases, angioplasty was attempted before stent placement; in five, stents were placed immediately after failed angioplasty; and in two, due to restenosis after angioplasty. Procedures involved a 10mm diameter, 7-10cm length Wallstent in eight cases, and a 10mm diameter, 8cm length Hanaro stent in one. In all cases, clinical follow-up, which included physical examination and the measurement of venous resistance pressure during hemodialysis, was performed. The follow-up period was between 5 months and 1 year 7 months. Repeated intervention was performed if restenosis was detected. The stenotic sites were in eight cases the site of a previous subclavian venous line, and in one, the site of anatomic narrowing at the thoracic inlet of the subclavian vein. The technical success rate was 100%;a resulting complication was stent migration into the right atrium in one case in which a Hanaro stent had been used; this was removed by snaring. During follow-up of the eight patients in whon stent placement was successful, restenosis developed in three cases. This occurred during the 7th, 8th, and 15th month, respectively. Two such cases were treated by balloon dilatation. In hemodialytic shunt-related subclavian vein stenosis, treatment involving the use of a self-expandable metallic stent is useful, especially for treating a lesion which has not responded to angioplasty with a high patency rate.

  4. Hemodialysis shunts-related subclavian vein stenosis : treatment with self-expandable metallic stent

    International Nuclear Information System (INIS)

    Kim, Sang Gyee; Lee, Young Chul; Shin, Sang Soo; Kim, Yun Hyeon; Kim, Jae Kyu; Kang, Heoung Keun; Jeong, Sang Young; Choi, Su Jin Na

    1999-01-01

    To evaluate the usefulness of placement of self-expandable stents in hemodialytic shunt-related subclavian vein stenosis. Self-expandable metallic stent was placed in nine patients with hemodialytic shunt-related subclavian vein stenosis. In seven cases, angioplasty was attempted before stent placement; in five, stents were placed immediately after failed angioplasty; and in two, due to restenosis after angioplasty. Procedures involved a 10mm diameter, 7-10cm length Wallstent in eight cases, and a 10mm diameter, 8cm length Hanaro stent in one. In all cases, clinical follow-up, which included physical examination and the measurement of venous resistance pressure during hemodialysis, was performed. The follow-up period was between 5 months and 1 year 7 months. Repeated intervention was performed if restenosis was detected. The stenotic sites were in eight cases the site of a previous subclavian venous line, and in one, the site of anatomic narrowing at the thoracic inlet of the subclavian vein. The technical success rate was 100%;a resulting complication was stent migration into the right atrium in one case in which a Hanaro stent had been used; this was removed by snaring. During follow-up of the eight patients in whon stent placement was successful, restenosis developed in three cases. This occurred during the 7th, 8th, and 15th month, respectively. Two such cases were treated by balloon dilatation. In hemodialytic shunt-related subclavian vein stenosis, treatment involving the use of a self-expandable metallic stent is useful, especially for treating a lesion which has not responded to angioplasty with a high patency rate

  5. Gianturco expandable wire stents for treatment of superior vena cava syndrome secondary to lung carcinoma

    International Nuclear Information System (INIS)

    Rosch, J.; Bedell, J.; Putnam, J.; Antonovic, R.; Uchida, B.

    1986-01-01

    Two patients with superior vena cava syndrome (SVCS) secondary to lung carcinoma which recurred after maximum-dose radiation therapy were treated with placement of modified Gianturco expandable wire stents constructed in the authors' research laboratory. Symptoms of SVCS disappeared in 24 hours after stent placement, and the patients remained asymptomatic to their last follow-up, 2 1/2 months after the procedure (to the submission of this abstract). Both stents were widely patent at that time on superior vena cavograms and draining well the head, neck, and upper extremity circulation to the right atrium

  6. Removal of self expandable metallic airway stent: A rare case report

    OpenAIRE

    Chawla, Rakesh K.; Madan, Arun; Singh, Ishwar; Mudoiya, Rahul; Chawla, Aditya; Gupta, Radha; Chawla, Kiran; Chhabra, Roopam

    2013-01-01

    Covered self expandable metallic airway stents (SEMS) have been used for benign tracheal stenosis, post intubation tracheal stenosis, tracheal burn or trauma, tracheo-broncho-malacia, and extrinsic compression of trachea. Their placement is considered to be permanent, with open surgery the only way to remove the stent, though there are few cases reports of their removal with the bronchoscope, but the complications after their removal are very high. In our patient, one and a half years after p...

  7. Stone extraction balloon-guided repeat self-expanding metal stent placement

    Institute of Scientific and Technical Information of China (English)

    Hyung; Hun; Kim; Jeong; Seop; Moon; Soo; Hyung; Ryu; Jung; Hwan; Lee; You; Sun; Kim

    2010-01-01

    Self-expanding metal stent (SEMS) placement offers safe and effective palliation in patients with upper gastrointestinal obstruction due to a malignancy. Well described complications of SEMS placement include tumor growth, obstruction, and stent migration. SEMS occlusions are treated by SEMS redeployment, argon plasma coagulation application, balloon dilation, and surgical bypass. At our center, we usually place the second SEMS into the first SEMS if there is complete occlusion by the tumor. We discovered a...

  8. Balloon-Expandable Stent Graft for Treating Uretero-Iliac Artery Fistula

    Energy Technology Data Exchange (ETDEWEB)

    Guntau, Moritz, E-mail: guntau@med.uni-marburg.de [Philipps University, Department of Diagnostic and Interventional Radiology, Marburg University Hospital (Germany); Hegele, Axel [Philipps University, Department of Urology and Pediatric Urology, Marburg University Hospital (Germany); Rheinheimer, Stephan [Philipps University, Department of Diagnostic and Interventional Radiology, Marburg University Hospital (Germany); Hofmann, Rainer [Philipps University, Department of Urology and Pediatric Urology, Marburg University Hospital (Germany); Mahnken, Andreas H. [Philipps University, Department of Diagnostic and Interventional Radiology, Marburg University Hospital (Germany)

    2017-06-15

    PurposeTo evaluate the safety, efficacy and outcome of percutaneous balloon-expandable covered stent graft placement for uretero-iliac artery fistula (UAF) treatment.MethodsThis retrospective study evaluated the single-center experience of percutaneous balloon-expandable covered stent graft placement (ADVANTA™, Atrium Hudson, NH, USA) in UAF. Data were obtained from a prospective institutional database. Patient follow-up included complications, symptoms recurrence and mortality rate.ResultsTen UAFs in eight patients (3 males; 5 females) with a mean age of 64.5 (35–77) years were identified. All patients had a history pelvic malignancy, extirpative surgery (n = 6), long-term ureteral stenting (n = 7) and pelvic radiation (n = 5). All procedures were completed successfully without complications. Thirty-day mortality rate was zero. At a median follow-up of 6 (1–60) months, one patient suffered recurrent hematuria requiring a secondary stent graft placement 26 months after the initial treatment. During follow-up, five patients died of the underlying disease (43, 66, 105, and 183 and 274 days after the last procedure).ConclusionPercutaneous balloon-expandable stent graft placement in UAF is a safe and effective treatment option. Implantation of stent grafts should be considered as treatment of choice in UAF.

  9. Esophageal carcinoma treatment with self-expanding covered stent implanted in esophagus

    International Nuclear Information System (INIS)

    Liu Mingguo; Ji Yan; He Nengwei

    2006-01-01

    Objective: To investigate the clinical significance of the treatment to esophageal cancer by self- expanding covered stent implanted into esophagus. Methods: Under fluoroscopic guidance and with guidance wire , 20 self-expanding covered stents were implanted into stenotic part of esophagus to recanalize the esophagus, then follow up to observe the clinical symptom improved. Results: Technical success was obtained 20 cases without any complication. Clinical symptom were improved in shot time. Conclusions: self-expanding covered stent is implanted in stenotic part of esophageal carcinoma to treat esophageal stenosis and enable to improved clinical symptom in shot time, if combined with transcatheter arterial infusion and embolization, Radiotherapy, Chinese medical treatment, it enable to lengthen life time remarkably. (authors)

  10. The treatment of complex airway diseases with inverted Y-shaped self-expandable metal stent

    International Nuclear Information System (INIS)

    Li Jianming; Jia Guangzhi

    2011-01-01

    Objective: To investigate the application and therapeutic effects of inverted Y-shaped self-expandable metal airway stent in treating complex airway diseases (stenosis or fistula). Methods: According to the distinctive anatomic structure and the pathological changes of complex airway stenosis or fistula, the inverted y-shaped self-expandable metal airway stent was designed. Under fluoroscopic monitoring, a total of 12 inverted Y-shaped self-expandable metal stents were implanted in 12 patients with complex airway diseases. Results: Stent placement in the trachea-bronchial tree was technically successful in all patients. After the operation, the symptom of dyspnea was immediately relieved and the bucking following food intake disappeared. The general physical condition and living quality were much improved in all patients. Conclusion: The use of inverted Y-shaped self-expandable metal airway stent for the management of complex airway stenosis involving the tracheal carina was a simple and safe procedure and it has satisfactory short-term clinical results. (authors)

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

    Science.gov (United States)

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

    2017-01-01

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

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

    Science.gov (United States)

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

    2015-07-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

  14. Mechanical Recanalization of Cerebral Artery Embolic Occlusion Using a Self-Expanding Stent: Experimental Analysis in Canine Model

    International Nuclear Information System (INIS)

    Choi, Jin Woo; Kim, Snag Joon; Lee, Deok Hee; Suh, Dae Chul

    2011-01-01

    To evaluate the feasibility of a self-expanding stent for acute embolic occlusion, and recanalization mechanism by histologic examination. Five mongrel dogs were used as study subjects. Each vertebral artery was occluded, and a self-expanding stent was used for recanalization. We evaluated the technical success rate for the placement of the stent to the targeted vessel, the recanalization rate, and residual stenosis. We obtained two specimens of the stented vertebral arteries for histologic evaluation. One dog died of an unknown cause during the induction of anesthesia. In two dogs, only one side of the vertebral artery was used, whereas both vertebral arteries were used in the remaining dogs. A total of six vertebral arteries were successfully occluded. The technical success rate for stenting without complication was 66.7%. The immediate recanalization rate after stenting was 100%. The residual stenosis was 35.6 ± 18.6%. On microscopic examination, the stent concentrically displaced the clot and the clot was captured between the stent mesh and arterial wall. Self-expanding stents were effective in revascularizing the cerebrovascular embolic occlusion. The self-expanding stent seemed to achieve recanalization by pushing the clot to the arterial wall and capturing the clot between the stent mesh and arterial wall.

  15. Mechanical Recanalization of Cerebral Artery Embolic Occlusion Using a Self-Expanding Stent: Experimental Analysis in Canine Model

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jin Woo; Kim, Snag Joon; Lee, Deok Hee; Suh, Dae Chul [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, Ulsan University College of Medicine, Seoul (Korea, Republic of)

    2011-07-15

    To evaluate the feasibility of a self-expanding stent for acute embolic occlusion, and recanalization mechanism by histologic examination. Five mongrel dogs were used as study subjects. Each vertebral artery was occluded, and a self-expanding stent was used for recanalization. We evaluated the technical success rate for the placement of the stent to the targeted vessel, the recanalization rate, and residual stenosis. We obtained two specimens of the stented vertebral arteries for histologic evaluation. One dog died of an unknown cause during the induction of anesthesia. In two dogs, only one side of the vertebral artery was used, whereas both vertebral arteries were used in the remaining dogs. A total of six vertebral arteries were successfully occluded. The technical success rate for stenting without complication was 66.7%. The immediate recanalization rate after stenting was 100%. The residual stenosis was 35.6 {+-} 18.6%. On microscopic examination, the stent concentrically displaced the clot and the clot was captured between the stent mesh and arterial wall. Self-expanding stents were effective in revascularizing the cerebrovascular embolic occlusion. The self-expanding stent seemed to achieve recanalization by pushing the clot to the arterial wall and capturing the clot between the stent mesh and arterial wall.

  16. Malignant inferior vena cava obstruction involving right atrium. Palliative treatment with self expandable metallic stent

    International Nuclear Information System (INIS)

    Shao Guoliang; Wang Jianhua; Zhou Kangrong; Yan Zhiping

    2001-01-01

    Objective: To investigate the safety and efficacy of placement of self-expandable metallic stent within right atrium and inferior vena cava (ICV) in patients with malignant ICV obstruction involving right atrium. Methods: There were 5 male patients with advanced hepatocellular carcinoma, aged from 42 to 65 years (mean 56.3 years). The malignancies invaded right atrium and ICV simultaneously, and caused obstruction of ICV. These patients presented symptoms and signs of obstruction of ICV such as hepatomegaly, ascites, edema of lower extremities. 'Z' type stainless steel stents (7.5-10.0 cm in length and 2.5 cm in diameter) were selected for these patients. Part (1.0-3.0 cm in length) of stent was placed in right atrium and the rest was in ICV. Results: All of stents were placed successfully and obstructed ICV reopened. The symptoms of obstruction of ICV relieved or disappeared. There were no recurrence of symptoms of obstruction of ICV and any cardiac complication related to placement of stents in follow-up period (67-188 days). Conclusion: Placement of self-expandable metallic stent within right atrium and ICV in treatment of patients with malignant ICV obstruction involving right atrium is one of the safe and effective methods

  17. Heparin-bonded, expanded polytetrafluoroethylene-lined stent graft in the treatment of femoropopliteal artery disease: 1-year results of the VIPER (Viabahn Endoprosthesis with Heparin Bioactive Surface in the Treatment of Superficial Femoral Artery Obstructive Disease) trial.

    Science.gov (United States)

    Saxon, Richard R; Chervu, Arun; Jones, Paul A; Bajwa, Tanvir K; Gable, Dennis R; Soukas, Peter A; Begg, Richard J; Adams, John G; Ansel, Gary M; Schneider, Darren B; Eichler, Charles M; Rush, Michael J

    2013-02-01

    To evaluate the performance of a heparin-bonded, expanded polytetrafluoroethylene (ePTFE)-lined nitinol endoprosthesis in the treatment of long-segment occlusive disease of the femoropopliteal artery (FPA) and to identify factors associated with loss of patency. In a single-arm, prospective, 11-center study (VIPER [Gore Viabahn Endoprosthesis with Heparin Bioactive Surface in the Treatment of Superficial Femoral Artery Obstructive Disease] trial), 119 limbs (113 patients; 69 men; mean age, 67 y), including 88 with Rutherford category 3-5 disease and 72 with Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC II) C or D lesions of the FPA, underwent stent graft implantation. The mean lesion length was 19 cm; 56% of lesions were occlusions. Follow-up evaluations included color duplex ultrasonography in all patients, with patency defined as a peak systolic velocity ratio20% was 70% (P = .047). Primary patency was not significantly affected by device diameter (5 vs 6 vs 7 mm) or lesion length (≤20 cm vs>20 cm). The 30-day major adverse event rate was 0.8%. The heparin-bonded, ePTFE/nitinol stent graft provided clinical improvement and a primary patency rate of 73% at 1 year in the treatment of long-segment FPA disease. Careful sizing of the device relative to vessel landing zones is essential for achieving optimal outcomes. Copyright © 2013 SIR. Published by Elsevier Inc. All rights reserved.

  18. Short-term results of self-expanding metal stents for acute malignant large bowel obstruction

    DEFF Research Database (Denmark)

    Kobborg, M; Broholm, M; Frostberg, E

    2017-01-01

    AIM: Self-expanding metal stents (SEMSs) can be used as a palliative treatment or to initially decompress colon prior to definitive surgery (as a so-called 'bridge to surgery'). The purpose of this study was to investigate the efficacy and safety of SEMS used as palliation and bridge to surgery...... for malignant large bowel obstruction. METHOD: A multicentre retrospective study was conducted from January 2010 to December 2013 to identify patients undergoing stent placement for acute large bowel obstruction. Patients were included from four Danish colorectal centres. Outcomes identified included clinical...... success, 30-day mortality, stent related complications and surgery related complications. Furthermore, we analysed for predictive factors for successful stenting. Clinical success was defined as relief of obstructive symptoms, without the need of other additional surgical interventions during the hospital...

  19. Self-expandable metal stents for obstructing colonic and extracolonic cancer

    DEFF Research Database (Denmark)

    van Hooft, Jeanin E; van Halsema, Emo E; Vanbiervliet, Geoffroy

    2014-01-01

    as a bridge to elective surgery is not recommended as a standard treatment of symptomatic left-sided malignant colonic obstruction (strong recommendation, high quality evidence). 3 For patients with potentially curable but obstructing left-sided colonic cancer, stent placement may be considered......, and Evaluation (GRADE) system was adopted to define the strength of recommendations and the quality of evidence. Main recommendations The following recommendations should only be applied after a thorough diagnostic evaluation including a contrast-enhanced computed tomography (CT) scan. 1 Prophylactic colonic...... stent placement is not recommended. Colonic stenting should be reserved for patients with clinical symptoms and imaging evidence of malignant large-bowel obstruction, without signs of perforation (strong recommendation, low quality evidence). 2 Colonic self-expandable metal stent (SEMS) placement...

  20. Successful stent-in-stent insertion of an expandable metallic stent covered with polyuretane placed to obliterate a large bronchial fistula after chemoradiotherapy for inoperable lung cancer

    International Nuclear Information System (INIS)

    Minami, Hiroya; Tsubota, Noriaki; Miyamoto, Yoshifumi; Yoshimura, Masahiro; Obayashi, Kayoko; Takada, Yoshiki

    1999-01-01

    Bronchial fistulas in cases of inoperable lung cancer caused by radiochemotherapy are quite refractory and generally cannot be surgically closed. A 45-year-old man with squamous cell carcinoma in the right lung underwent two courses of induction chemotherapy (135 mg CDDP, 5 mg VDS, 13.5 mg MMC) and radiation therapy (2 Gy x 22 times) for invasion of the right main bronchus, the pulmonary artery and superior vena cava. Just before the end of the second course, the empyem second to the bronchial fistula caused by tumor necrosis developed in the right upper bronchus, and fenestration was performed. After the operation, his condition improved remarkably, however the fistula enlarged into the right main bronchus and the purulent discharge flowed into the left lung. An expandable metallic stent (EMS) covered with polyuretane was inserted in the trachea and the left main bronchus to break aspiration pneumonia. As the covered EMS was too unstable to be fixed, a bare EMS was inserted in a stent-in-stent fashion. After the procedure he was followed at the O.P.D. and lived a relatively comfortable life for 9 months until his death due to tumor. We inserted the covered EMS in a stent-in-stent fashion to successfully obliterate a large bronchial fistula. (author)

  1. Treatment of tracheobronchial stenosis with a self-expandable metallic stents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Soo; Jeon, Seok Chol; Choi, Chul Seung; Choi, Yo Won; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1994-07-15

    We analysed the role of modified Gianturco self-expandable stents in the treatment of tracheobronchial stenosis in 13 patients. We inserted modified Gianturco self-expandable stents under the fluoroscopic and bronchoscopic guidance. There were stenosis in the trachea(n=2), the right main bronchus(n=2), and the left main bronchus(n=9). The causes of the stenosis were endobronchial tuberculosis(n=10), intubation granuloma(n=1), restenosis after surgical reconstruction(n=2). Dyspnea or wheezing was improved within 1 or 2 days following the procedure. There were 32% and 22% respective increase in average FEV1 and FVC. Lung perfusion scan showed 9.6% increase of perfusion in the involved lung. No complications related to the procedure were encountered. During follow-up period of up to 31 months, 2 patients showed tracheal or bronchial restenosis, at 3 and 6 months, retrospectively. There was a distal migration of the stents in one case. During the follow up period after stent insertion, improvement of the obstructive changes and dyspnea persisted in 10 out of 13 patients. The modified Gianturco self-expandable metallic stents may be a good choice for the treatment of tracheobronchial stenosis, either as a primary treatment, or when the reconstruction failed.

  2. Expandable metallic stents in the palliative treatment of malignant tracheobronchial stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Woong; Jung, Gyoo Sik; Kim, Seong Min; Lee, Seung Ryong; Kim, Hyun Sook; Huh, Jin Do; Joh, Young Duk [Kosin Medical College, Pusan (Korea, Republic of)

    1998-05-01

    The purpose of this study is to report the outcome of using expandable metallic stent in the management of malignant tracheobronchial stenosis with dyspnea. Under fluoroscopic and bronchoscopic guidance, seven patients with malignant airway stenosis were treated with ten expandable metallic stents. The cause of stenosis was metastasis from esophageal cancer in five patients, recurrent adenoid cystic carcinoma of the trachea in one, and primary lung cancer in one. The major sites of obstruction were the trachea in four patients, the left main bronchus in one, the trachea and left main bronchus in one, and the trachea and both bronchi in one. Chest radiography (n=7), bronchoscopy (n=5), pulmonary function test (PFT)(n=3), and spirometry(n=1) were performed before and after stent placement. In all seven patients, the stent was successfully placed at the lesion sites and dyspnea began to improve immediately. After the procedure, chest radiography and bronchoscopy showed an increase in airway diameter. After the procedure, chest radiography and bronchoscopy showed an increase in airway diameter. After stent placement, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) improved 53% and 56%, respectively. Peak flow velocity also changed from 46 L/min to 200 L/min. During median follow-up of 67 (41-1565) days, one stent migration occurred. In one patient, proximal tumor overgrowth occurred, and in one, tumor ingrowth was treated with balloon dilatation. For in the palliative treatment of malignant tracheobronchial stenosis with dyspnea, placement of expandable metal stents is safe and effective. (author). 21 refs., 1 tabs., 3 figs.

  3. Expandable metallic stents in the palliative treatment of malignant tracheobronchial stenosis

    International Nuclear Information System (INIS)

    Park, Jong Woong; Jung, Gyoo Sik; Kim, Seong Min; Lee, Seung Ryong; Kim, Hyun Sook; Huh, Jin Do; Joh, Young Duk

    1998-01-01

    The purpose of this study is to report the outcome of using expandable metallic stent in the management of malignant tracheobronchial stenosis with dyspnea. Under fluoroscopic and bronchoscopic guidance, seven patients with malignant airway stenosis were treated with ten expandable metallic stents. The cause of stenosis was metastasis from esophageal cancer in five patients, recurrent adenoid cystic carcinoma of the trachea in one, and primary lung cancer in one. The major sites of obstruction were the trachea in four patients, the left main bronchus in one, the trachea and left main bronchus in one, and the trachea and both bronchi in one. Chest radiography (n=7), bronchoscopy (n=5), pulmonary function test (PFT)(n=3), and spirometry(n=1) were performed before and after stent placement. In all seven patients, the stent was successfully placed at the lesion sites and dyspnea began to improve immediately. After the procedure, chest radiography and bronchoscopy showed an increase in airway diameter. After the procedure, chest radiography and bronchoscopy showed an increase in airway diameter. After stent placement, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) improved 53% and 56%, respectively. Peak flow velocity also changed from 46 L/min to 200 L/min. During median follow-up of 67 (41-1565) days, one stent migration occurred. In one patient, proximal tumor overgrowth occurred, and in one, tumor ingrowth was treated with balloon dilatation. For in the palliative treatment of malignant tracheobronchial stenosis with dyspnea, placement of expandable metal stents is safe and effective. (author). 21 refs., 1 tabs., 3 figs

  4. Expandable stents in digestive pathology – present use in an emergency hospital

    Directory of Open Access Journals (Sweden)

    Mădălina Ilie

    2016-04-01

    Full Text Available Introduction: Self expandable metal stents (SEMS are developed lately, as an effective and safe, less invasive alternative of surgery for the treatment of malignant intestinal/biliary obstruction. Recently, SEMS are also introduced in benign pathology. Aim: The aim of this presentation is to report a retrospective analysis of the total number of SEMS placed for esophageal, enteral, colorectal and biliary obstruction during the last 3 years in Clinical Emergency Hospital Bucharest, as well to review the literature published on this issue. Methods: Between 2013-2015 in Clinical Emergency Hospital Bucharest, we have placed: 232 esophageal stents, 23 enteral stents, 5 colonic stents and 75 biliary stents under radiologic guidance. The main parameters followed were represented by: sex, age, grades of obstruction, stent diameter and type, immediate and late complications and survival rate. Results: Regarding the esophageal stenting, most of the indications were malignant obstruction (155 cases of esophageal cancer and 30 cases of extrinsic compression, but also for esophageal fistula, peptic stenosis and even traumatic esophageal rupture. The majority of the enteral and colonic stents were inserted for malignant obstructions, having only 2 cases with benign obstructions. This is also the case for biliary stenting, were most of the indications were represented by pancreatic cancer. Technical and clinical success rates were approximately 92% and 80%, respectively. There were no major complications of perforation, bleeding, or death. Conclusions: SEMS insertion can be performed safely, with minimal complications and hospitalization allowing the restart of oral feeding and improvement of nutritional status for the digestive obstruction or jaundice disappearance in case of biliary obstruction. It represents the first option for unresectable digestive/biliary malignant obstruction.

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

    Science.gov (United States)

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

    2015-07-01

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

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

    Science.gov (United States)

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

    2015-05-01

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

  7. Fracture and Collapse of Balloon-Expandable Stents in the Bilateral Common Iliac Arteries Due to Shiatsu Massage

    Energy Technology Data Exchange (ETDEWEB)

    Ichihashi, Shigeo, E-mail: shigeoichihashi@yahoo.co.jp; Higashiura, Wataru; Itoh, Hirofumi; Sakaguchi, Shoji; Kichikawa, Kimihiko [Nara Medical University, Department of Radiology (Japan)

    2012-12-15

    We report a case of stent fracture and collapse of balloon-expandable stents caused by shiatsu massage. A 76-year-old man presented with complaints of intermittent claudication of the right lower extremity. Stenoses of the bilateral common iliac arteries (CIAs) were detected. Balloon-expandable stents were deployed in both CIAs, resulting in resolution of symptoms. Five months later, pelvis x-ray showed collapse of both stents. Despite the stent collapse, the patient was asymptomatic, and his ankle brachial index values were within the normal range. Further history showed that the patient underwent daily shiatsu therapy in the umbilical region, which may have triggered collapse of the stent. Physicians should advise patients to avoid compression of the abdominal wall after implantation of a stent in the iliac artery.

  8. Fracture and Collapse of Balloon-Expandable Stents in the Bilateral Common Iliac Arteries Due to Shiatsu Massage

    International Nuclear Information System (INIS)

    Ichihashi, Shigeo; Higashiura, Wataru; Itoh, Hirofumi; Sakaguchi, Shoji; Kichikawa, Kimihiko

    2012-01-01

    We report a case of stent fracture and collapse of balloon-expandable stents caused by shiatsu massage. A 76-year-old man presented with complaints of intermittent claudication of the right lower extremity. Stenoses of the bilateral common iliac arteries (CIAs) were detected. Balloon-expandable stents were deployed in both CIAs, resulting in resolution of symptoms. Five months later, pelvis x-ray showed collapse of both stents. Despite the stent collapse, the patient was asymptomatic, and his ankle brachial index values were within the normal range. Further history showed that the patient underwent daily shiatsu therapy in the umbilical region, which may have triggered collapse of the stent. Physicians should advise patients to avoid compression of the abdominal wall after implantation of a stent in the iliac artery.

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

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

    Science.gov (United States)

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

    2015-04-28

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

  11. Ultraflex precision colonic stent placement as a bridge to surgery in patients with malignant colon obstruction

    DEFF Research Database (Denmark)

    Fregonese, D.; Naspetti, R.; Ferrer, S.

    2008-01-01

    Background: Emergency surgery for malignant colon obstruction entails relatively high morbidity and mortality rates and typically necessitates a 2-step resection. These problems might be potentially mitigated by placement of a self-expanding metal stent (SEMS) as a bridge to surgery. A nitinol co...

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

    Science.gov (United States)

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

    2008-12-01

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

  13. Clinical application of self-expandable metallic stents in the treatment of malignant tracheal stenosis under general anesthesia

    International Nuclear Information System (INIS)

    Wang Weitao; Shi Haibin; Yang Zhengqiang; Liu Sheng; Zhou Chungao; Zhao Linbo; Xia Jinguo; Li Linsun

    2009-01-01

    Objective: To evaluate the safety and efficacy of self-expandable metallic stent placement for the treatment of malignant tracheal stenosis under general anesthesia and fluoroscopic guidance. Methods: Under general anesthesia the placement of self-expandable metallic stent was performed in 10 patients with malignant tracheal stenosis, the procedure was completed under fluoroscopic guidance in all patients. Results: Successful tracheal stenting was achieved in all 10 patients. In one patient, a Y-shaped stent was used as the tracheal carina was involved in the airway stenosis. The symptoms of dyspnea and asthma were markedly improved immediately after the implantation of stent in all patients. Conclusion: Tracheal implantation of self-expandable metallic stent under general anesthesia and fluoroscopic guidance is a safe and effective treatment for malignant tracheal stenosis, it can promptly relieve various symptoms caused by malignant tracheal stenosis and obviously improve patient's living quality, therefore,t his technique is of great value in clinical practice. (authors)

  14. Trial of self-expandable metallic stents in the palliation of tracheo ...

    African Journals Online (AJOL)

    Trial of self-expandable metallic stents in the palliation of tracheo-oesophageal fistula in carcinoma of the oesophagus. ... Over half of the patients in the TOF group had concomitant pneumonia at presentation with decreased survival (p = 0.010) and a hazard ratio of 10.86. Two patients died, on days 4 and 7 respectively.

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

    NARCIS (Netherlands)

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

    2015-01-01

    To provide an overview of the clinical outcomes of self-expandable metal stent (SEMS) placement for malignant gastric outlet obstruction (MGOO). A systematic literature search was performed in PubMed of the literature published between January 2009 and March 2015. Only prospective studies that

  16. Self-expandable metal stent placement versus emergency resection for malignant proximal colon obstructions

    NARCIS (Netherlands)

    Amelung, F.J.; Draaisma, W.A.; Consten, E.C.; Siersema, P.D.; Borg, F. ter

    2017-01-01

    BACKGROUND: Traditionally, all patients with a malignant obstruction of the proximal colon (MOPC) are treated with emergency resection. However, recent data suggest that Self-expandable metallic stent (SEMS) placement could lower mortality and morbidity rates. This study therefore aimed to compare

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

    Science.gov (United States)

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

    2016-09-01

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

  18. Compliance Study of Endovascular Stent Grafts Incorporated with Polyester and Polyurethane Graft Materials in both Stented and Unstented Zones

    Directory of Open Access Journals (Sweden)

    Ying Guan

    2016-08-01

    Full Text Available Compliance mismatch between stent graft and host artery may induce complications and blood flow disorders. However, few studies have been reported on stent graft compliance. This study aims to explore the deformation and compliance of stent graft in stented and unstented zones under three pressure ranges. Compliance of two stent grafts incorporated with polyurethane graft (nitinol-PU and polyester graft (nitinol-PET materials respectively were tested; the stents used in the two stent grafts were identical. For the circumferential deformation of the stent grafts under each pressure range, the nitinol-PET stent graft was uniform in both zones. The nitinol-PU stent graft was circumferentially uniform in the stented zone, however, it was nonuniform in the unstented zone. The compliance of the PU graft material was 15 times higher than that of the PET graft. No significant difference in compliance was observed between stented and unstented zones of the nitinol-PET stent graft regardless of the applied pressure range. However, for the nitinol-PU stent graft, compliance of the unstented PU region was approximately twice that of the stented region; thus, compliance along the length of the nitinol-PU stent graft was not constant and different from that of the nitinol-PET stent graft.

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

    Science.gov (United States)

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

    2013-07-01

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

  20. Efficacy of Self-Expandable Metallic Stent Inserted for Refractory Hemorrhage of Duodenal Cancer

    Directory of Open Access Journals (Sweden)

    Takashi Orii

    2016-05-01

    Full Text Available Because of advances in the technology of gastrointestinal endoscopy and improvements in the quality of stents, it has become routine to place a stent as palliative therapy for malignant gastrointestinal obstruction. On the other hand, stent placement for malignant gastrointestinal hemorrhage has scarcely been reported, although it may be performed for hemorrhage of the esophageal varicose vein. We recently experienced a patient with refractory hemorrhage from an unresectable duodenal cancer who underwent placement of a self-expandable metallic stent (SEMS and thereafter had no recurrence of the hemorrhage. A 46-year-old man underwent laparotomy to radically resect a cancer in the third portion of the duodenum, which invaded widely to the superior mesenteric vein and its branches and was considered unresectable. After stomach-partitioning gastrojejunostomy was performed, chemotherapy was initiated according to the regimen of chemotherapy of far advanced gastric cancer. One year and 4 months after induction of chemotherapy, gastrointestinal hemorrhage occurred. Upper gastrointestinal endoscopy revealed the hemorrhage oozing from the duodenal cancer, and endoscopic hemostasis, such as injection of hypertonic saline epinephrine and argon plasma coagulation, was unsuccessful. Twenty days after emergence of the hemorrhage, an endoscopic covered SEMS was placed with confirmation by fluoroscopy. Immediately after placement of the stent, the tarry stool stopped and the anemia ceased to progress. The recurrence of the hemorrhage has not been confirmed without migration of the stent. SEMS is an effective hemostatic procedure for malignant refractory hemorrhage.

  1. In-vitro release of anti-proliferative paclitaxel from novel balloon-expandable polycaprolactone stents

    International Nuclear Information System (INIS)

    Liu, Shih-Jung; Hsiao, Chao-Ying; Chen, Jan-Kan; Liu, Kuo-Sheng; Lee, Cheng-Hung

    2011-01-01

    This report investigated the in-vitro release characteristics of paclitaxel from novel balloon-expandable polycaprolactone stents. Polycaprolactone stents were first manufactured by a lab-made micro-injection molding machine. Paclitaxel and polylactide-polyglycolide (PLGA) copolymer were dissolved in acetonitrile and were coated onto the surface of the stents by a spray coating device, which was designed and built especially for this study. An elution method was utilized to characterize the in-vitro release characteristics of paclitaxel. The high performance liquid chromatography (HPLC) analysis showed that biodegradable stents could provide sustained release of paclitaxel for more than 70 days. Various process parameters that controlled the release rate of paclitaxel were studied. The experimental results suggested that the total period of drug release could be prolonged by adopting 75:25 PLGA copolymers, employing multi-layer coatings, and increasing the drug loading. In addition, the effectiveness of eluted paclitaxel on cell behavior was examined. The results showed that the eluted drug could effectively inhibit the proliferation of smooth muscle cells. - Research Highlights: → We investigate the in-vitro release characteristics of paclitaxel from polycaprolactone stents. → Biodegradable stents provide sustained release of paclitaxel for more than 70 days. → The eluted drug effectively inhibits the proliferation of smooth muscle cells.

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

    Science.gov (United States)

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

    2017-06-01

    Patients with locally advanced esophageal cancer can have significant dysphagia. Nutritional support during neoadjuvant therapy is often delivered via nasoenteric or percutaneous feeding tubes. These approaches do not allow for per-oral feeding. Evaluate the safety and efficacy of fully covered self-expanding metal esophageal stents for nutritional support during neoadjuvant therapy. This was a pilot, prospective study at a single tertiary center. From March 2012 to May 2013, consecutive patients with esophageal cancer eligible for neoadjuvant therapy were enrolled. Metal stents were placed prior to starting neoadjuvant therapy. Data were collected at baseline and predetermined intervals until an endpoint (surgery or disease progression). Outcomes included dysphagia grade, satisfaction of swallowing score, nutritional status (weight, serum albumin), impact on surgery, and adverse events. Fourteen stents were placed in 12 patients (59.1 ± 9.5 years, 11 men, 1 woman). Dysphagia grade (pre 3.4 ± 0.5 vs post 0.2 ± 0.4, p esophageal cancer, self-expanding metal stents are safe and effective in relieving dysphagia and maintaining nutrition. They allow patients to eat orally, thereby improving patient satisfaction. The presence of an in situ stent did not interfere with surgery.

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

    Science.gov (United States)

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

    2015-11-21

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

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

    Science.gov (United States)

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

    2014-03-01

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

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

    Science.gov (United States)

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

    2017-07-01

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

  6. The technique study and primary clinical application of inverted Y-shaped self-expandable metal airway stent

    International Nuclear Information System (INIS)

    Han Xinwei; Wu Gang; Ma Ji; Yang Ruimin; Guan Sheng; Ma Nan; Wang Yanli

    2007-01-01

    Objective: To investigate the feasibility and primary therapeutic effect of inverted Y-shaped self-expandable metal stent for complex airway stenosis. Methods: On the standpoint of the peculiar anatomic structure and the pathological changes of complex airway stenosis, we designed the inverted Y-shaped self-expandable metal stent. Under the fluoroscopic guidance, 7 stents were implanted in 7 cases of airway complex stenosis. Results: The inverted Y-shaped self-expandable metal stents were placed seccussfully, with instantaneous relief of dyspnea and improvement of living quality. Conclusion: The placement of inverted Y-shaped self-expandable metal stent is feasible and safe for treating airway complex stenosis. (authors)

  7. Insertion of a self-expandable metallic stent in canine lacrimal Sac : a long-term evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Sung, Kyu Bo; Yoon, Hyun Ki [Univ. of Ulsan, Ulsan (Korea, Republic of). College of Medicine; Kwon, Soon Tae [Chungnam National Univ., Taejon (Korea, Republic of). Medical School; Lee, Ho Jung; Lee, In Chul; Kim, Tae Hyung; Park, Sang Soo; Huh, Soo Jin [Univ. of Ulsan, Ulsan (Korea, Republic of). College of Medicine

    1998-01-01

    To evaluate the feasibility and long-term outcome of the use of self-expandable metallic Z-stents in the canine lacrimal sac. Stent placement was technically successful and well tolerated in all but one lacrimal sac, in which the stent was misplaced. At three and six months after stent placement, stent wires were not encased by epithelium, but at nine months, and one, two and three years after placement, six of the 12 stents had become encased in a proliferation of this where the stent wires contacted the lacrimal sac wall. In no lacrimal system in which stent placement had been successful was migration, stenosis or obstruction of the lacrimal system observed. One misplaced stent caused obstruction of the lacrimal sac, however . In 11 of 12 case (92%), fluoroscopic placement of an expandable metallic stent in the canine lacrimal sac was successful: in 6 of 8 cases (75%), the stent wires became encased by a proliferation of mucosa, but during long-term follow-up of 9 months to 3 years, no obstruction was observed. (author). 20 refs., 1 tab., 5 figs.

  8. Insertion of a self-expandable metallic stent in canine lacrimal Sac : a long-term evaluation

    International Nuclear Information System (INIS)

    Song, Ho Young; Sung, Kyu Bo; Yoon, Hyun Ki; Kwon, Soon Tae; Lee, Ho Jung; Lee, In Chul; Kim, Tae Hyung; Park, Sang Soo; Huh, Soo Jin

    1998-01-01

    To evaluate the feasibility and long-term outcome of the use of self-expandable metallic Z-stents in the canine lacrimal sac. Stent placement was technically successful and well tolerated in all but one lacrimal sac, in which the stent was misplaced. At three and six months after stent placement, stent wires were not encased by epithelium, but at nine months, and one, two and three years after placement, six of the 12 stents had become encased in a proliferation of this where the stent wires contacted the lacrimal sac wall. In no lacrimal system in which stent placement had been successful was migration, stenosis or obstruction of the lacrimal system observed. One misplaced stent caused obstruction of the lacrimal sac, however . In 11 of 12 case (92%), fluoroscopic placement of an expandable metallic stent in the canine lacrimal sac was successful: in 6 of 8 cases (75%), the stent wires became encased by a proliferation of mucosa, but during long-term follow-up of 9 months to 3 years, no obstruction was observed. (author). 20 refs., 1 tab., 5 figs

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

    Science.gov (United States)

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

    2013-09-07

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

  10. Intraluminal Palmaz stent implantation. First clinical case report on a balloon-expandable vessel prosthesis

    Energy Technology Data Exchange (ETDEWEB)

    Palmaz, J C; Richter, G M; Noeldge, G; Kauffmann, G W; Wenz, W

    1987-12-01

    A 74-year-old patient suffering from severe iliac artery stenosis and claudication was chosen to be the first candidate in the world to receive the Palmaz stent, a balloon-expandable intraluminal stent. This procedure was done in the Department of Radiology, University of Freiburg, FRG. The intervention and postprocedural course were uneventful. His walking distance improved from less than 100 m to unlimited walking capacity. The intra-arterial pressure gradient and ankle-arm pressure ratio also returned to normal.

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

    Science.gov (United States)

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

    2017-03-01

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

  12. Delayed ischemic cecal perforation despite optimal decompression after placement of a self-expanding metal stent: report of a case

    DEFF Research Database (Denmark)

    Knop, Filip Krag; Pilsgaard, Bo; Meisner, Søren

    2004-01-01

    Endoscopic deployment of self-expanding metal stents offers an alternative to surgical intervention in rectocolonic obstructions. Reported clinical failures in the literature are all related to the site of stent placement. We report a case of serious intra-abdominal disease after technically...... and clinically successful stent deployment: a potentially dangerous situation of which the surgeon should be aware. A previously healthy 72-year-old female was referred to our department with symptoms of an obstructing colorectal tumor. Successful stent placement resulted in resolution of the obstructive......, probably caused by ischemic conditions developed before stent-decompression of the colon was revealed during the operation. The patient died in the postoperative course. We discuss the observation of patients treated with self-expanding metal stents based on the selection-strategy used to allocate patients...

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

    Science.gov (United States)

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

    2018-02-01

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

  14. Palliation of gastrointestinal obstruction with expandable metallic stents: 3 case reports

    International Nuclear Information System (INIS)

    Langhorne, N.B.; Asch, M.R.; Jaffer, N.

    1997-01-01

    Interventional radiologists are often asked to assist in the care of patients with advanced malignant disease. Frequent clinical problems include dysphagia due to proximal involvement of the gastrointestinal (GI) tract or bowel obstruction as a result of more distal compression. Although a number of endoscopic and surgical options are available, the placement of expandable metallic stents in the bowel lumen has recently been reported as efficacious, safe and cost-effective. We present our experience with placement of stents in the small and large bowel, describing the clinical scenarios, the reasons for stent placement, and the technique and results in each of 3 cases and comparing our experience with those of others, as reported in the literature. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Pausawasadi, Nonthalee [Department of Medicine, Siriraj Hospital, Mahidol University, Bangkok (Thailand); Soontornmanokul, Tanassanee; Rerknimitr, Rungsun [Department of Medicine, Chulalongkorn University, Bangkok (Thailand)

    2012-02-15

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

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

    International Nuclear Information System (INIS)

    Pausawasadi, Nonthalee; Soontornmanokul, Tanassanee; Rerknimitr, Rungsun

    2012-01-01

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

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

    Science.gov (United States)

    Pausawasadi, Nonthalee; Soontornmanokul, Tanassanee

    2012-01-01

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

  18. Arterial stenting with self-expandable and balloon-expandable endoprostheses

    NARCIS (Netherlands)

    W.J. van der Giessen (Wim); P.W.J.C. Serruys (Patrick); L.J. van Woerkens (L.); K.J. Beatt (Kevin); W.J. Visser (Willy); J.F. Jongkind; R.H. van Bremen (Robert); E. Ridderhof; H. van Loon (Heleen); L.K. Soei (Lou Kie); H.M.M. van Beusekom (Heleen); P.D. Verdouw (Pieter)

    1990-01-01

    textabstractCoronary angioplasty is complicated by acute occlusion (within 24 hours) and late restenosis (within 6 months) in 2-5% and 20-40% of the cases, respectively. Vascular endoprostheses (stents) may provide the cardiologist with a solution to some of these complications. Several

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

    Science.gov (United States)

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

    2004-12-01

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

  20. Palliation of Malignant Upper Gastrointestinal Obstruction with Self-Expandable Metal Stent

    Energy Technology Data Exchange (ETDEWEB)

    Morikawa, Soichiro; Suzuki, Azumi; Nakase, Kojiro; Yasuda, Kenjiro [Kyoto Second Red Cross Hospital, Kyoto (Japan)

    2012-02-15

    To assess the technical success, ability to eat, complications and clinical outcomes of patients with self-expandable metal stent (SEMS) placed for malignant upper gastrointestinal (GI) obstruction. Data was collected retrospectively on patients who underwent SEMS placement for palliation of malignant upper GI obstruction by reviewing hospital charts from June 1998 to May 2011. Main outcome measurements were technical success, gastric outlet obstruction scoring system (GOOSS) score before and after treatment, complications, and survival. A total of 82 patients underwent SEMS placement with malignant upper GI obstruction. The initial SEMS placement was successful in 77 patients (93.9%). The mean GOOSS score was 0.56 before stenting and 1.92 (p < 0.001) after treatment. Complications arose in 12 patients (14.6%): stent migration in 1 patient (1.2%), perforation in 1 (1.2%), and obstruction of stent due to tumor ingrowth in 10 (12.2%). The median survival time after stenting was 52 days (6-445). SEMS placement is an effective and safe treatment for palliation of malignant upper GI obstruction. It provides lasting relief in dysphagia and improves the QOL of patients.

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

    Science.gov (United States)

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

    2013-12-01

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

  2. Palliation of Malignant Upper Gastrointestinal Obstruction with Self-Expandable Metal Stent

    International Nuclear Information System (INIS)

    Morikawa, Soichiro; Suzuki, Azumi; Nakase, Kojiro; Yasuda, Kenjiro

    2012-01-01

    To assess the technical success, ability to eat, complications and clinical outcomes of patients with self-expandable metal stent (SEMS) placed for malignant upper gastrointestinal (GI) obstruction. Data was collected retrospectively on patients who underwent SEMS placement for palliation of malignant upper GI obstruction by reviewing hospital charts from June 1998 to May 2011. Main outcome measurements were technical success, gastric outlet obstruction scoring system (GOOSS) score before and after treatment, complications, and survival. A total of 82 patients underwent SEMS placement with malignant upper GI obstruction. The initial SEMS placement was successful in 77 patients (93.9%). The mean GOOSS score was 0.56 before stenting and 1.92 (p < 0.001) after treatment. Complications arose in 12 patients (14.6%): stent migration in 1 patient (1.2%), perforation in 1 (1.2%), and obstruction of stent due to tumor ingrowth in 10 (12.2%). The median survival time after stenting was 52 days (6-445). SEMS placement is an effective and safe treatment for palliation of malignant upper GI obstruction. It provides lasting relief in dysphagia and improves the QOL of patients.

  3. Broncho-vascular fistulas from self-expanding metallic stents: A retrospective case review

    Directory of Open Access Journals (Sweden)

    Chirag Choudhary

    2013-01-01

    Full Text Available To highlight a potentially fatal complication of broncho-vascular fistula arising from the self expanding metallic stent (SEMS placement. We retrospectively analyzed five patients with benign and malignant airway diseases, who developed tracheo/broncho-vascular fistulas following SEMS placement in our tertiary care setting. All patients received either Wallstent or Ultraflex® stent (Boston Scientific, Natick, MA between 1999 and 2007. All patients had received adjunct therapy such as balloon bronchoplasty, laser therapy or electrocautery. Most patients presented with massive hemoptysis. A total of 483 SEMS were placed during this period. SEMS placement can be complicated by Broncho-vascular fistula formation. True incidence and precise time interval between the insertion of stent and onset of this complication is unknown. Additional therapeutic modalities to maintain stent patency may enhance the risk of fistula formation. SEMS should only be used in a select sub-group of patients, after exhaustive evaluation of other treatment options. These cases provide evidence that broncho-vascular fistulas can develop at any time following SEMS placement, suggesting the need for a more cautious approach, especially while using them for a long term management. In benign airway disease, the stent should be removed as soon as healing has taken place.

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

    NARCIS (Netherlands)

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

    2015-01-01

    BACKGROUND: Self-expandable metal stents (SEMSs) are increasingly used for the treatment of benign biliary strictures (BBSs). A new fully covered SEMS (FCSEMS) with flared ends and high conformability was designed to prevent migration of the stent. OBJECTIVE: To evaluate the efficacy of a novel

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

    NARCIS (Netherlands)

    Walter, D.; Laleman, W.; Jansen, J.M.; Milligen de Wit, A.W. van; Weusten, B.L.; Boeckel, P.G. van; Hirdes, M.M.; Vleggaar, F.P.; Siersema, P.D.

    2015-01-01

    BACKGROUND: Self-expandable metal stents (SEMSs) are increasingly used for the treatment of benign biliary strictures (BBSs). A new fully covered SEMS (FCSEMS) with flared ends and high conformability was designed to prevent migration of the stent. OBJECTIVE: To evaluate the efficacy of a novel

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

    OpenAIRE

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

    2013-01-01

    Background/Aims The use of self-expandable metallic stents (SEMS) is an established palliative treatment for malignant stenosis in the gastrointestinal tract; therefore, its application to benign stenosis is expected to be beneficial because of the more gradual and sustained dilatation in the stenotic portion. We aimed in this prospective observational study to evaluate the efficacy and safety of temporary SEMS placement in benign pyloric stenosis. Methods Twenty-two patients with benign sten...

  7. Long-Term Results after Placement of Aortic Bifurcation Self-Expanding Stents: 10 Year Mortality, Stent Restenosis, and Distal Disease Progression

    International Nuclear Information System (INIS)

    Houston, J. Graeme; Bhat, Raj; Ross, Rose; Stonebridge, Peter A.

    2007-01-01

    Purpose. To retrospectively evaluate the 10 year follow-up results in patients who had 'kissing' self-expanding stent aortic bifurcation reconstruction. Methods. Forty-three patients were treated with 'kissing' self-expanding stents for aortoiliac occlusive disease. Early follow-up with clinical and ankle brachial pressure indices (ABPI) was performed at 3, 6, 12, and 24 months and with intra-arterial digital subtraction angiography at 12-24 months; clinical and angiographic follow-up was performed for symptom recurrence up to 10 years after treatment. Retrospective record review was performed to assess mortality, clinical patency, angiographic patency, and secondary assisted patency of both stents and downstream peripheral vessels at 5 and 10 years follow-up. Results. The 2 year primary angiographic and secondary assisted stent patencies were 89% and 93%, respectively. At 10 years follow-up in 40 patients the mortality was 38% (due to myocardial infarction, stroke, chronic renal failure, malignancy, and liver failure). At 5 and 10 years follow-up the primary clinical stent patency was 82% and 68%, and the secondary assisted stent patency 93% and 86%, respectively. At 5 and 10 years, the distal vessel patency was 86% and 72%, and the secondary assisted distal vessel patency treated by surgical or endovascular techniques was 94% and 88%, respectively. At 10 years there was no limb loss. Conclusion. The long-term (10 year) results of aortic bifurcation arterial self-expanding stent placement in patients with arterial occlusive disease show a 10 year primary stent patency rate of 68% but a secondary assisted patency rate of 86%. In addition there is a high overall mortality due to other cardiovascular causes and the rate of distal disease progression and loss of patency is similar to the loss of stent patency rate

  8. Self-Expandable Metal Stent for Closure of a Large Leak after Total Gastrectomy

    Directory of Open Access Journals (Sweden)

    G. Curcio

    2010-08-01

    Full Text Available In recent years, self-expandable metallic stents (SEMSs have emerged as a promising treatment alternative for the bridging and sealing of esophageal perforations and extensive anastomotic leaks after esophageal resection or total gastrectomy. A 56-year-old woman underwent a total gastrectomy with Roux-en-Y end-to-side esophagojejunostomy for a gastric signet ring cell carcinoma. Ten days later, esophagogastroduodenoscopy showed a 2 cm fistula in the distal end of the Roux limb of the anastomosis. This was confirmed by gastrografin esophagography. The patient was started on total parenteral nutrition. Having deemed clipping treatment for this fistula unfeasible, we decided to insert a partially silicone-coated SEMS (Evolution Controlled Release Esophageal Stent System, Cook Medical, Winston-Salem, N.C., USA. The stent was removed after ten days. Gastrografin esophagography showed no further contrast extravasation, and esophagogastroduodenoscopy showed closure of the fistula. No clinical complications were observed, and the patient was able to start normal per os nutrition. In conclusion, the treatment of symptomatic leaks in patients who have undergone esophagojejunostomy is challenging, and leakage from the jejunal stump can be a potentially serious complication. In the treatment of leakage after total gastrectomy, plastic stents (which are either too light or exercise too little radial force and totally covered metallic stents may not adhere sufficiently to the esophagojeujunal walls and, as a result, migrate beyond the anastomosis. The promising results of this report suggest that early stenting, using a partially silicone-coated SEMS, is a feasible alternative to surgical treatment in this category of patients.

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

    Science.gov (United States)

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

    2014-07-01

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

  10. Successful technical and clinical outcome using a second generation balloon expandable coronary stent for transplant renal artery stenosis: Our experience.

    Science.gov (United States)

    Salsamendi, Jason; Pereira, Keith; Baker, Reginald; Bhatia, Shivank S; Narayanan, Govindarajan

    2015-10-01

    Transplant renal artery stenosis (TRAS) is a vascular complication frequently seen because of increase in the number of renal transplantations. Early diagnosis and management is essential to optimize a proper graft function. Currently, the endovascular treatment of TRAS using angioplasty and/or stenting is considered the treatment of choice with the advantage that it does not preclude subsequent surgical correction. Treatment of TRAS with the use of stents, particularly in tortuous transplant renal anatomy presents a unique challenge to an interventional radiologist. In this study, we present three cases from our practice highlighting the use of a balloon-expandable Multi-Link RX Ultra coronary stent system (Abbott Laboratories, Abbott Park, Illinois, USA) for treating high grade focal stenosis along very tortuous renal arterial segments. Cobalt-Chromium alloy stent scaffold provides excellent radial force, whereas the flexible stent design conforms to the vessel course allowing for optimal stent alignment.

  11. Vascular stents: Coupling full 3-D with reduced-order structural models

    International Nuclear Information System (INIS)

    Avdeev, I; Shams, M

    2010-01-01

    Self-expanding nitinol stents are used to treat peripheral arterial disease. The peripheral arteries are subjected to a combination of mechanical forces such as compression, torsion, bending, and contraction. Most commercially available peripheral self-expanding stents are composed of a series of sub-millimeter V-shaped struts, which are laser-cut from a nitinol tube and surface-treated for better fatigue performance. The numerical stent models must accurately predict location and distribution of local stresses and strains caused by large arterial deformations. Full 3-D finite element non-linear analysis of an entire stent is computationally expensive to the point of being prohibitive, especially for longer stents. Reduced-order models based on beam or shell elements are fairly accurate in capturing global deformations, but are not very helpful in predicting stent failure. We propose a mixed approach that combines the full 3-D model and reduced-order models. Several global-local, full 3-D/reduced-order finite element models of a peripheral self-expanding stent were validated and compared with experimental data. The kinematic constraint method used to couple various elements together was found to be very efficient and easily applicable to commercial FEA codes. The proposed mixed models can be used to accurately predict stent failure based on realistic (patient-specific), non-linear kinematic behavior of peripheral arteries.

  12. Covered self-expandable metallic stent placement for a post-operative malignant anastomotic stricture secondary to recurrent gastric cancer

    International Nuclear Information System (INIS)

    Lee, Woon Ha; Jung, Gyoo Sik; Kim, Kyu Jong; Lee, Sang Ho; Ko, Ji Ho; Jeong, Kyung Soon

    2007-01-01

    To evaluate the technical feasibility and clinical effectiveness of stent placement for the treatment of a post-operative malignant anastomotic stricture secondary to recurrent gastric cancer. Under fluoroscopic guidance, one or two covered stents were placed in 20 consecutive patients (age range, 44-75 years) with an anastomotic stricture due to a recurrent gastric malignancy. Before stent placement, all patients had severe nausea and recurrent vomiting after ingestion. Stent placement was technically successful for all patients, and no procedural complications occurred. After stent placement, 18 of 20 (90.0%) patients were able to ingest at least a liquid diet and had a markedly decreased incidence of vomiting. During the follow-up of 2-116 weeks (mean, 25.5 weeks), stent migration occurred in two patients (10.0%) on one day after the procedure. All patients with stent migration were treated successfully by means of placing a second stent. Three patients showed a recurrence of the stricture due to tumor overgrowth; two of the patients were treated with coaxial placement of a second stent. Another patient refused additional management. Covered self-expandable metallic stent placement seems to be technically feasible and effective for palliative treatment of a post-operative malignant anastomotic stricture secondary to recurrent gastric cancer

  13. Covered self-expandable metallic stent placement for a post-operative malignant anastomotic stricture secondary to recurrent gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Woon Ha; Jung, Gyoo Sik; Kim, Kyu Jong; Lee, Sang Ho [Gospel Hospital, College of Medicine, Kosin University, Busan (Korea, Republic of); Ko, Ji Ho [Masan Samsung Medical Center, Sungkyunkwan University School of University, Masan (Korea, Republic of); Jeong, Kyung Soon [University of Ulsan Colleg of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2007-09-15

    To evaluate the technical feasibility and clinical effectiveness of stent placement for the treatment of a post-operative malignant anastomotic stricture secondary to recurrent gastric cancer. Under fluoroscopic guidance, one or two covered stents were placed in 20 consecutive patients (age range, 44-75 years) with an anastomotic stricture due to a recurrent gastric malignancy. Before stent placement, all patients had severe nausea and recurrent vomiting after ingestion. Stent placement was technically successful for all patients, and no procedural complications occurred. After stent placement, 18 of 20 (90.0%) patients were able to ingest at least a liquid diet and had a markedly decreased incidence of vomiting. During the follow-up of 2-116 weeks (mean, 25.5 weeks), stent migration occurred in two patients (10.0%) on one day after the procedure. All patients with stent migration were treated successfully by means of placing a second stent. Three patients showed a recurrence of the stricture due to tumor overgrowth; two of the patients were treated with coaxial placement of a second stent. Another patient refused additional management. Covered self-expandable metallic stent placement seems to be technically feasible and effective for palliative treatment of a post-operative malignant anastomotic stricture secondary to recurrent gastric cancer.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  16. Iliocaval Confluence Stenting for Chronic Venous Obstructions

    Energy Technology Data Exchange (ETDEWEB)

    Graaf, Rick de, E-mail: r.de.graaf@mumc.nl [Maastricht University Medical Centre (MUMC), Department of Radiology (Netherlands); Wolf, Mark de, E-mail: markthewolf@gmail.com [Maastricht University Medical Centre (MUMC), Department of Surgery (Netherlands); Sailer, Anna M., E-mail: anni.sailer@mumc.nl [Maastricht University Medical Centre (MUMC), Department of Radiology (Netherlands); Laanen, Jorinde van, E-mail: jorinde.van.laanen@mumc.nl; Wittens, Cees, E-mail: c.wittens@me.com [Maastricht University Medical Centre (MUMC), Department of Surgery (Netherlands); Jalaie, Houman, E-mail: hjalaie@ukaachen.de [University Hospital Aachen, Department of Surgery (Germany)

    2015-10-15

    PurposeDifferent techniques have been described for stenting of venous obstructions. We report our experience with two different confluence stenting techniques to treat chronic bi-iliocaval obstructions.Materials and MethodsBetween 11/2009 and 08/2014 we treated 40 patients for chronic total bi-iliocaval obstructions. Pre-operative magnetic resonance venography showed bilateral extensive post-thrombotic scarring in common and external iliac veins as well as obstruction of the inferior vena cava (IVC). Stenting of the IVC was performed with large self-expandable stents down to the level of the iliocaval confluence. To bridge the confluence, either self-expandable stents were placed inside the IVC stent (24 patients, SECS group) or high radial force balloon-expandable stents were placed at the same level (16 patients, BECS group). In both cases, bilateral iliac extensions were performed using nitinol stents.ResultsRecanalization was achieved for all patients. In 15 (38 %) patients, a hybrid procedure with endophlebectomy and arteriovenous fistula creation needed to be performed because of significant involvement of inflow vessels below the inguinal ligament. Mean follow-up was 443 ± 438 days (range 7–1683 days). For all patients, primary, assisted-primary, and secondary patency rate at 36 months were 70, 73, and 78 %, respectively. Twelve-month patency rates in the SECS group were 85, 85, and 95 % for primary, assisted-primary, and secondary patency. In the BECS group, primary patency was 100 % during a mean follow-up period of 134 ± 118 (range 29–337) days.ConclusionStenting of chronic bi-iliocaval obstruction shows relatively high patency rates at medium follow-up. Short-term patency seems to favor confluence stenting with balloon-expandable stents.

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

    Science.gov (United States)

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

    2014-04-01

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

  18. Self-expanding stent-assisted middle cerebral artery recanalization: technical note

    International Nuclear Information System (INIS)

    Sauvageau, Eric; Levy, Elad I.

    2006-01-01

    Investigation into pharmacological and mechanical means of improving recanalization rates by intraarterial therapy has led to technological development. Angiographic recanalization has been associated with improvement in clinical outcome. A clot retriever has recently joined an imperfect armamentarium for intraarterial stroke therapy. In this report, we describe successful recanalization of an acute thrombotic occlusion of the inferior division of the middle cerebral artery (MCA) achieved with a self-expanding stent. An 82-year-old woman with a history of coronary atherosclerosis and previous cerebellar hemorrhage presented with a National Institutes of Health Stroke Scale (NIHSS) score of 11. Perfusion computed tomography imaging showed a left MCA territory deficit. Diffusion-weighted magnetic resonance (MR) imaging revealed a small punctiform insular hyperintensity. Angiography documented occlusion of the inferior division of the left MCA (Thrombolysis in Myocardial Infarction or Thrombolysis in Cerebral Infarction, TIMI/TICI, grade 0). Intraarterial delivery of eptifibatide to the occlusion site failed to recanalize the vessel. Deployment of a self-expanding stent in the occluded segment resulted in complete revascularization of the distal vascular bed. Angiography performed on the next day confirmed patency of the stented vessel segment (TIMI/TICI 3). The patient was discharged 3 days after the procedure (NIHSS 3). MR angiography obtained 3 months after the procedure documented left MCA patency. This technique may have a role worthy of further investigation in acute stroke therapy. (orig.)

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

    Science.gov (United States)

    van Halsema, Emo E; van Hooft, Jeanin E

    2015-01-01

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

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

    Science.gov (United States)

    van Halsema, Emo E; van Hooft, Jeanin E

    2015-02-16

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

  1. Treatment of intracranial atherosclerotic stenoses with balloon dilatation and self-expanding stent deployment (WingSpan)

    Energy Technology Data Exchange (ETDEWEB)

    Henkes, H. [Robert Janker Klinik, Bonn (Germany); Alfried Krupp Krankenhaus, Klinik fuer Radiologie und Neuroradiologie, Essen (Germany); Miloslavski, E.; Lowens, S.; Reinartz, J. [Robert Janker Klinik, Bonn (Germany); Liebig, T.; Kuehne, D. [Alfried Krupp Krankenhaus, Klinik fuer Radiologie und Neuroradiologie, Essen (Germany)

    2005-03-01

    The endovascular treatment of atherosclerotic intracranial arterial stenoses has previously been based on balloon dilatation or the deployment of a balloon expandable stent. Both methods have advantages (balloon: flexibility; balloon expandable stent: high radial force) and drawbacks (balloon: risk of elastic recoil and dissection; balloon expandable stent: limited flexibility, risk of injury to the vessel due to excessive straightening, overexpansion at ends of stent). A new combination of balloon dilatation, followed by the deployment of a self-expanding microstent has been applied in 15 patients with atherosclerotic arterial stenoses, symptomatic despite medical treatment. An anatomically and clinically adequate result was achieved in all patients. The initial degree of stenosis was 72% (mean). Balloon dilatation resulted in an average residual stenosis of 54% (mean), reduced further to a mean of 38% after stent deployment. Arterial dissection, occlusion of the target artery or symptomatic distal emboli was not encountered. In one patient, a side branch occlusion occurred after dilatation of a M1 stenosis, with complete neurological recovery. All patients were either stable or improved 4 weeks after the treatment. Recurrent TIA did not occur in any patient. Balloon dilatation and subsequent deployment of a self-expandable stent for the treatment of symptomatic intracranial arterial stenoses combines the advantages of both techniques and allows a rapid, clinically effective and technically safe treatment of these frequently challenging lesions. (orig.)

  2. Treatment of intracranial atherosclerotic stenoses with balloon dilatation and self-expanding stent deployment (WingSpan)

    International Nuclear Information System (INIS)

    Henkes, H.; Miloslavski, E.; Lowens, S.; Reinartz, J.; Liebig, T.; Kuehne, D.

    2005-01-01

    The endovascular treatment of atherosclerotic intracranial arterial stenoses has previously been based on balloon dilatation or the deployment of a balloon expandable stent. Both methods have advantages (balloon: flexibility; balloon expandable stent: high radial force) and drawbacks (balloon: risk of elastic recoil and dissection; balloon expandable stent: limited flexibility, risk of injury to the vessel due to excessive straightening, overexpansion at ends of stent). A new combination of balloon dilatation, followed by the deployment of a self-expanding microstent has been applied in 15 patients with atherosclerotic arterial stenoses, symptomatic despite medical treatment. An anatomically and clinically adequate result was achieved in all patients. The initial degree of stenosis was 72% (mean). Balloon dilatation resulted in an average residual stenosis of 54% (mean), reduced further to a mean of 38% after stent deployment. Arterial dissection, occlusion of the target artery or symptomatic distal emboli was not encountered. In one patient, a side branch occlusion occurred after dilatation of a M1 stenosis, with complete neurological recovery. All patients were either stable or improved 4 weeks after the treatment. Recurrent TIA did not occur in any patient. Balloon dilatation and subsequent deployment of a self-expandable stent for the treatment of symptomatic intracranial arterial stenoses combines the advantages of both techniques and allows a rapid, clinically effective and technically safe treatment of these frequently challenging lesions. (orig.)

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

    Science.gov (United States)

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

    2016-09-01

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

  4. Influence of paclitaxel-eluting expandable metallic stent on tissue hyperplasia: an experimental study in a canine tracheal model

    International Nuclear Information System (INIS)

    Shin, Ji Hoon; Kim, Jung Sun; Kim, Tae Hyung; Kim, Eun Young; Choi, Won Chan; Woo, Chul Woong; Di, Zhenhai; Song, Ho Young; Yuk, Soon Hong; Lee, Yong Seok

    2005-01-01

    To evaluate the efficacy of a paclitaxel-eluting expandable metallic stent in reducing tissue hyperplasia following stent placement in a canine tracheal model. Nine paclitaxel-eluting stents (drug stent, DS) consisting of a proximal bare part and a distal polyurethane-covered part were placed in the trachea of nine dogs and nine control stents (control stent, CS) were placed in the other nine dogs. The dogs were scheduled to be sacrificed 12 weeks after stent placement. Gross and histological factors, such as epithelial erosion/ulcer, granulation tissue thickness and inflammatory cell infiltration were evaluated after each dog was sacrificed. There were no procedure-related complications or malpositioning of any of the stents. One CS migrated less than eight weeks following stent placement. Four dogs (one DS and three CS dogs) died between three and five weeks following stent placement. Therefore, pathologic specimens were obtained from eight DS and five CS dogs. Epithelial erosion/ulcer or inflammatory cell infiltration was slightly more prominent in the DS cases than in the CS cases, in both the bare part and the covered part. However, the data was not statistically significant. Granulation tissue thickness was lower in the DS cases than in the CS cases in both the bare part (mean, 3.63-mm vs. 4.37-mm) and the covered part (mean, 1.75-mm vs. 2,78 mm), but the data was also statistically insignificant. Although the data was not statistically significant, placement of paclitaxel-eluting expandable metallic stent demonstrates a tendency toward a decrease in granulation tissue thickness in canine tracheal models

  5. Influence of paclitaxel-eluting expandable metallic stent on tissue hyperplasia: an experimental study in a canine tracheal model

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ji Hoon; Kim, Jung Sun; Kim, Tae Hyung; Kim, Eun Young; Choi, Won Chan; Woo, Chul Woong; Di, Zhenhai; Song, Ho Young [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Yuk, Soon Hong [Hannam University, College of Engineering, Daejeon (Korea, Republic of); Lee, Yong Seok [Wonkwang University College of Medicine, Iksan (Korea, Republic of)

    2005-07-15

    To evaluate the efficacy of a paclitaxel-eluting expandable metallic stent in reducing tissue hyperplasia following stent placement in a canine tracheal model. Nine paclitaxel-eluting stents (drug stent, DS) consisting of a proximal bare part and a distal polyurethane-covered part were placed in the trachea of nine dogs and nine control stents (control stent, CS) were placed in the other nine dogs. The dogs were scheduled to be sacrificed 12 weeks after stent placement. Gross and histological factors, such as epithelial erosion/ulcer, granulation tissue thickness and inflammatory cell infiltration were evaluated after each dog was sacrificed. There were no procedure-related complications or malpositioning of any of the stents. One CS migrated less than eight weeks following stent placement. Four dogs (one DS and three CS dogs) died between three and five weeks following stent placement. Therefore, pathologic specimens were obtained from eight DS and five CS dogs. Epithelial erosion/ulcer or inflammatory cell infiltration was slightly more prominent in the DS cases than in the CS cases, in both the bare part and the covered part. However, the data was not statistically significant. Granulation tissue thickness was lower in the DS cases than in the CS cases in both the bare part (mean, 3.63-mm vs. 4.37-mm) and the covered part (mean, 1.75-mm vs. 2,78 mm), but the data was also statistically insignificant. Although the data was not statistically significant, placement of paclitaxel-eluting expandable metallic stent demonstrates a tendency toward a decrease in granulation tissue thickness in canine tracheal models.

  6. Role of Self-Expandable Metal Stents in Acute Variceal Bleeding

    Directory of Open Access Journals (Sweden)

    Fuad Maufa

    2012-01-01

    Full Text Available Acute variceal bleeding continues to be associated with significant mortality. Current standard of care combines hemodynamic stabilization, antibiotic prophylaxis, pharmacological agents, and endoscopic treatment. Rescue therapies using balloon tamponade or transjugular intrahepatic portosystemic shunt are implemented when first-line therapy fails. Rescue therapies have many limitations and are contraindicated in some cases. Placement of fully covered self-expandable metallic stent is a promising therapeutic technique that can be used to control bleeding in cases of refractory esophageal bleeding as an alternative to balloon tamponade. These stents can be left in place for as long as two weeks, allowing for improvement in liver function and institution of a more definitive treatment.

  7. Temporary stenting and retrieval of the self-expandable, intracranial stent in acute middle cerebral artery occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Sang Hyun; Chung, Tae-Sub [Yonsei University College of Medicine, Department of Radiology, Gangnam Severance Hospital, Seoul (Korea); Lee, Kyung-Yul [Yonsei University College of Medicine, Department of Neurology, Gangnam Severance Hospital, Seoul (Korea); Hong, Chang Ki; Kim, Chang-Hyun [Yonsei University College of Medicine, Department of Neurosurgery, Gangnam Severance Hospital, Seoul (Korea); Kim, Byung Moon; Kim, Dong Ik [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea)

    2009-08-15

    We describe our experience in which a retrievable Enterprise stent was used as a temporary recanalization and embolectomy device in an acute middle cerebral artery (MCA) occlusion after urgent stenting for ipsilateral carotid artery stenosis. (orig.)

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

    Science.gov (United States)

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

    2015-10-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

  10. Self-Expandable Metallic Stent for the Palliative Treatment of Obstructing Left-Sided Colorectal Cancer under Fluoroscopic Guidance: A Comparison of the Clinical Results according to Stent Diameter

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Pyeong Guk; Hong, Hyun Pyo; Choi, Yoon Jung; Lee, Min Hee; Park, Hae Won; Chung, Eun Chul [Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Kim, Sam Soo [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of)

    2010-03-15

    To evaluate the feasibility, effectiveness, and safety of self-expandable metallic stent for the palliative treatment of obstructing left-sided colorectal cancer under fluoroscopic guidance, and to compare results according to the stent diameter. Under fluoroscopic guidance, 31 self-expandable metallic stents were placed into 25 patients for palliative purposes. The rates of technical success, clinical success, complications associated with stent insertion, patient survival, and primary stent patency were evaluated. The results were also compared between two groups: 13 patients using stents with a diameter of 22 mm and 12 patients using stents with a diameter of 26 mm. The technical and clinical success rates were 93.5 and 90.3%, respectively. The complications included severe abdominal pain (6.5%), minor rectal bleeding (9.7%), stent migration (9.7%), and tumor ingrowth or overgrowth (9.7%). No statistical differences in technical were detected between the two groups for the clinical success rate and complication rates. The mean survival time was 5.5 +- 1.4 months. The primary stent patency rates were 91.3% at 5 months, 85.2% at 10 months, and 77.4% at 15 months. The mean period of stent patency was 12.4 +- 2.6 months. The mean period of primary stent patency was 16.4 +- 2.6 months in the 26 mm stent group, and significantly higher than 5.4 +- 1.4 months in the 22 mm stent group (p=0.031). A self-expandable metallic stent under fluoroscopic guidance, for the palliative treatment of obstructing left-sided colorectal cancer, was feasible and effective, and yielded good clinical results. The period of primary stent patency of the 26 mm stent group was longer than the 22 mm stent group, and the complication rate was not significantly different between the two stent groups

  11. Self-Expandable Metallic Stent for the Palliative Treatment of Obstructing Left-Sided Colorectal Cancer under Fluoroscopic Guidance: A Comparison of the Clinical Results according to Stent Diameter

    International Nuclear Information System (INIS)

    Kang, Pyeong Guk; Hong, Hyun Pyo; Choi, Yoon Jung; Lee, Min Hee; Park, Hae Won; Chung, Eun Chul; Kim, Sam Soo

    2010-01-01

    To evaluate the feasibility, effectiveness, and safety of self-expandable metallic stent for the palliative treatment of obstructing left-sided colorectal cancer under fluoroscopic guidance, and to compare results according to the stent diameter. Under fluoroscopic guidance, 31 self-expandable metallic stents were placed into 25 patients for palliative purposes. The rates of technical success, clinical success, complications associated with stent insertion, patient survival, and primary stent patency were evaluated. The results were also compared between two groups: 13 patients using stents with a diameter of 22 mm and 12 patients using stents with a diameter of 26 mm. The technical and clinical success rates were 93.5 and 90.3%, respectively. The complications included severe abdominal pain (6.5%), minor rectal bleeding (9.7%), stent migration (9.7%), and tumor ingrowth or overgrowth (9.7%). No statistical differences in technical were detected between the two groups for the clinical success rate and complication rates. The mean survival time was 5.5 ± 1.4 months. The primary stent patency rates were 91.3% at 5 months, 85.2% at 10 months, and 77.4% at 15 months. The mean period of stent patency was 12.4 ± 2.6 months. The mean period of primary stent patency was 16.4 ± 2.6 months in the 26 mm stent group, and significantly higher than 5.4 ± 1.4 months in the 22 mm stent group (p=0.031). A self-expandable metallic stent under fluoroscopic guidance, for the palliative treatment of obstructing left-sided colorectal cancer, was feasible and effective, and yielded good clinical results. The period of primary stent patency of the 26 mm stent group was longer than the 22 mm stent group, and the complication rate was not significantly different between the two stent groups

  12. Delayed ischemic cecal perforation despite optimal decompression after placement of a self-expanding metal stent: report of a case

    DEFF Research Database (Denmark)

    Knop, Filip Krag; Pilsgaard, Bo; Meisner, Søren

    2004-01-01

    Endoscopic deployment of self-expanding metal stents offers an alternative to surgical intervention in rectocolonic obstructions. Reported clinical failures in the literature are all related to the site of stent placement. We report a case of serious intra-abdominal disease after technically...... and clinically successful stent deployment: a potentially dangerous situation of which the surgeon should be aware. A previously healthy 72-year-old female was referred to our department with symptoms of an obstructing colorectal tumor. Successful stent placement resulted in resolution of the obstructive...... condition. Three days after stent deployment, x-ray examinations revealed a small-bowel obstruction and emergency surgery was performed. Intraoperative findings demonstrated a segment of ileum fixated to the tumor in the small pelvis, resulting in the obstructive condition. Furthermore, a cecal perforation...

  13. Stent

    Science.gov (United States)

    ... Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Stent URL of this page: //medlineplus.gov/ency/article/002303.htm Stent To use the sharing features on this page, please enable JavaScript. A stent is a tiny tube placed into a hollow structure in your ...

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

    Science.gov (United States)

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

    2015-07-01

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

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

    Science.gov (United States)

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

    2016-12-01

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

  16. Temporary urethral covered stent - third year of experience

    International Nuclear Information System (INIS)

    Stojanovis, V.; Maksimovis, H.; Markovis, B.; Markovis, Z.

    2006-01-01

    Full text: In October 2003, a new generation of urethral stents ALLIUM, produced in Israel, were used at the Department of Interventional Radiology, CCS, in 18 patients with chronic stricture of bulbar urethra. The indications for insertion were determined according to well-known and recognized therapeutical protocols. The stent is made of nitinol wire with polyurethane cover. It is inserted under local anesthesia by a special self-expandable system that may be fixed or flexible. The stents we used were 3-6 cm long and 28 Fr wide. Radioscopic-assisted insertion was performed over formerly placed metal guide. Prior to insertion, balloon-catheter dilatation of stricture matching the stent width was carried out. Pre-insertion urethrotomy was performed in one case. The insertion technique is simple, presupposing the knowledge of older generations of techniques of urethral dilatation and insertion of self-expandable stents. The follow-up of results was done according to a priori established protocol including the following: UCG, uroflowmetry and interview with patients. Due to stent migration, the 'stent over stent' technique was applied in one case, while reposition by balloon-catheter outward traction was performed in two cases of caudal migration. No irritative discomforts were reported in the first 4 months after stent dwelling. Uroflowmetric controls verified at least four times better results than before the insertion. Given it is the question of covered stent, there is no possibility of proliferative secondary lumen obstruction. On account of soft structure and conic shape of posterior part of stent, no lesions of the external urethral sphincter were manifested. The stent is simply withdrawn after 6 months by outward traction using the forceps at the time when the stent construction turns into soft and straight wire. The first clinical experiences are very favorable and ALLIUM stent may be expected to be the stent of choice for chronic bulbar strictures

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

    Science.gov (United States)

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

    2017-05-01

    In recent years, knowledge concerning the mechanical properties of self-expandable metallic stents (SEMS) has increased. In a previous study, we defined traction force and traction momentum and reported that these characteristics are important for optimal stent deployment. However, traction force and traction momentum were represented as relative values and were not evaluated in various conditions. The purpose of the present study was to measure traction force in various situations assumed during SEMS placement. Traction force and traction momentum were measured in non-stricture, stricture, and angled stricture models using in-house equipment. Stricture and angled stricture models had significantly higher traction force and traction momentum than those of the non-stricture model (stricture vs non-stricture: traction force, 7.2 N vs 1.4 N, P stent influenced the traction force. Clinicians should be aware of the transition of the traction force and should schedule X-ray imaging during SEMS placement. © 2017 Japan Gastroenterological Endoscopy Society.

  18. Heparin-bonded covered stents versus bare-metal stents for complex femoropopliteal artery lesions: the randomized VIASTAR trial (Viabahn endoprosthesis with PROPATEN bioactive surface [VIA] versus bare nitinol stent in the treatment of long lesions in superficial femoral artery occlusive disease).

    Science.gov (United States)

    Lammer, Johannes; Zeller, Thomas; Hausegger, Klaus A; Schaefer, Philipp J; Gschwendtner, Manfred; Mueller-Huelsbeck, Stefan; Rand, Thomas; Funovics, Martin; Wolf, Florian; Rastan, Aljoscha; Gschwandtner, Michael; Puchner, Stefan; Ristl, Robin; Schoder, Maria

    2013-10-08

    nitinol stent in the treatment of TASC B, C and D lesions in superficial femoral artery occlusive disease; ISRCTN48164244). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  19. Safety and efficacy of a fully covered large-diameter self-expanding metal stent for the treatment of upper gastrointestinal perforations, anastomotic leaks, and fistula

    NARCIS (Netherlands)

    van den Berg, M. W.; Kerbert, A. C.; van Soest, E. J.; Schwartz, M. P.; Bakker, C. M.; Gilissen, L. P. L.; van Hooft, J. E.

    2016-01-01

    Upper gastrointestinal perforations, fistula, and anastomotic leaks are severe conditions with high mortality. Temporary endoscopic placement of fully covered self-expanding metal stent (fSEMS) has emerged as treatment option. Stent migration is a major drawback of currently used stents. Migration

  20. Malignant pyloro-duodenal obstruction: Role of self expandable metallic stents

    International Nuclear Information System (INIS)

    Qureshi, S.; Ghazanfar, S.; Quraishy, M.S.

    2014-01-01

    Objective: To determine the outcome of duodenal stenting in palliation of patients with malignant pyloric and duodenal obstruction. Methods: The non-randomised prospective descriptive study was conducted at the Endoscopy Suite, Surgical Unit-IV, Civil Hospital, Karachi, from December 2007 to November 2010. All patients presenting with inoperable ampullary, pancreatic or biliary cancers causing duodenal obstruction and patients with resectable malignancy but unfit for surgery were included. The procedure was carried out by a single expert endoscopist under local or general anaesthaesia as required. Boston Scientific stents of variable sizes were used. Follow-up was done at 1 week, 1 month and 6 months. Data analysis was done using SPSS 15. Results: Over the study period, 159 (60%) males and 6 (40%) females were included in the study. The male-to-female ratio was 2:3. The overall age ranged from 25-80 years with a mean of 52.67+-15.07 years. Primary diagnosis was pyloric carcinoma in 7(46.6%), carcinoma Gallbladder in 4(26.6%), Duodenal carcinoma in 3(20%) and carcinoma head of pancreas in 1(6.6%). Relief of symptoms were seen in 11 (73.3%), while complications were seen in 2 (13.3%). Stents were inserted with technical success in 14 (93%) patients. Clinical success was seen in 11 (73%), with a mean survival of 74.27+-40.7 days (range: 15-180 days). No statistical significance was found when comparing the survival time with age, gender and diagnosis. Conclusion: Use of self-expandable metallic stents for gastroduodenal malignancies appears to be a feasible, safe and effective method, especially in those patients with limited life expectancy. (author)

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Science.gov (United States)

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

    2014-03-01

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

  3. Prevention of Intracranial In-stent Restenoses: Predilatation with a Drug Eluting Balloon, Followed by the Deployment of a Self-Expanding Stent

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    Vajda, Zsolt, E-mail: Z.Vajda@klinikum-stuttgart.de; Guethe, Thomas, E-mail: T.Guethe@klinikum-stuttgart.de; Perez, Marta Aguilar, E-mail: M.Aguilar@klinikum-stuttgart.de; Kurre, Wiebke, E-mail: w.kurre@klinikum-stuttgart.de [Klinikum Stuttgart, Katharinenhospital, Klinik fuer Neuroradiologie, Neurozentrum (Germany); Schmid, Elisabeth, E-mail: ESchmid@klinikum-stuttgart.de; Baezner, Hansjoerg, E-mail: H.Baezner@klinikum-stuttgart.de [Klinikum Stuttgart, Klinik fuer Neurologie, Neurozentrum (Germany); Henkes, Hans, E-mail: hhhenkes@aol.com [Klinikum Stuttgart, Katharinenhospital, Klinik fuer Neuroradiologie, Neurozentrum (Germany)

    2013-04-15

    Stenting in intracranial atherosclerotic disease (ICAD) is increasingly debated, due to issues of procedural safety, technical efficacy, and in-stent recurrent stenoses (ISR). In the present study, feasibility, safety, and efficacy of angioplasty using a drug-eluting balloon (DEB) followed by the implantation of a self-expanding stent (Enterprise) were evaluated for the treatment of ICAD lesions. Fifty-two patients (median age: 71 years; range: 54-86 years; male/female ratio 37:15) underwent stenting of high-grade ICAD lesions between February 2010 and November 2011 in a single center. Angioplasty using a paclitaxel coated SeQuent Please (B. Braun, Germany) or DIOR (Eurocor, Germany) coronary PTCA balloon, followed by the implantation of a self-expanding stent (Enterprise, Codman, USA) was performed in 54 lesions. Angiographic and clinical follow-up was performed at 6 and 12 weeks, 6 and 12 months, and yearly thereafter. Technical success rate, periprocedural complications, occurrence of recurrent ischemic symptoms, and the development of an ISR were analyzed. Angioplasty using a DEB followed by stent implantation was successfully performed in 44 (81 %) cases. DEB insertion failed in 19 % of the cases and angioplasty was finally performed using a conventional PTCA balloon. The combined procedure related permanent neurologic morbidity and mortality rate (stroke, ICH, and subarachnoid hemorrhage) at 30 days and beyond was 5 %. Angiographic and clinical follow-up were obtained in 33 (61 %) lesions in 32 patients. Recurrent stenosis was seen in one (3 %) lesion. Angioplasty and stenting using a DEB is safe and yields encouragingly low ISR rates. Further technical developments to improve lesion accessibility are, nevertheless, mandatory.

  4. Prevention of Intracranial In-stent Restenoses: Predilatation with a Drug Eluting Balloon, Followed by the Deployment of a Self-Expanding Stent

    International Nuclear Information System (INIS)

    Vajda, Zsolt; Güthe, Thomas; Perez, Marta Aguilar; Kurre, Wiebke; Schmid, Elisabeth; Bäzner, Hansjörg; Henkes, Hans

    2013-01-01

    Stenting in intracranial atherosclerotic disease (ICAD) is increasingly debated, due to issues of procedural safety, technical efficacy, and in-stent recurrent stenoses (ISR). In the present study, feasibility, safety, and efficacy of angioplasty using a drug-eluting balloon (DEB) followed by the implantation of a self-expanding stent (Enterprise) were evaluated for the treatment of ICAD lesions. Fifty-two patients (median age: 71 years; range: 54–86 years; male/female ratio 37:15) underwent stenting of high-grade ICAD lesions between February 2010 and November 2011 in a single center. Angioplasty using a paclitaxel coated SeQuent Please (B. Braun, Germany) or DIOR (Eurocor, Germany) coronary PTCA balloon, followed by the implantation of a self-expanding stent (Enterprise, Codman, USA) was performed in 54 lesions. Angiographic and clinical follow-up was performed at 6 and 12 weeks, 6 and 12 months, and yearly thereafter. Technical success rate, periprocedural complications, occurrence of recurrent ischemic symptoms, and the development of an ISR were analyzed. Angioplasty using a DEB followed by stent implantation was successfully performed in 44 (81 %) cases. DEB insertion failed in 19 % of the cases and angioplasty was finally performed using a conventional PTCA balloon. The combined procedure related permanent neurologic morbidity and mortality rate (stroke, ICH, and subarachnoid hemorrhage) at 30 days and beyond was 5 %. Angiographic and clinical follow-up were obtained in 33 (61 %) lesions in 32 patients. Recurrent stenosis was seen in one (3 %) lesion. Angioplasty and stenting using a DEB is safe and yields encouragingly low ISR rates. Further technical developments to improve lesion accessibility are, nevertheless, mandatory.

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

    Science.gov (United States)

    Xue, Liang; Dai, Shiyao; Li, Zhi

    2010-11-01

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

  6. Insertion of self-expanding metal stent for treatment of malignant obstruction in a pregnant woman

    Directory of Open Access Journals (Sweden)

    Noelia Alonso-Lázaro

    2014-03-01

    Full Text Available Colorectal cancer (CRC is the second most frequent cancer both in incidence and mortality in women, especially in those over 60 years of age. Diagnosis in women at gestational age is rare, so its incidence during pregnancy is low. However, an increase in its diagnosis is expected during the next years because of the raise in the average age of pregnancy. In most cases, the diagnosis is delayed because symptoms related to CRC can be attributed to pregnancy itself. Up to 30 % of CRC cases may present as an intestinal obstruction. In this situation, the main objective is to solve the clinical emergency in the safest way for mother and fetus, together with performing an accurate diagnostic approach to offer the best possible therapeutic management knowing the limitations and difficulties related to pregnancy. The self-expanding metallic stent (SEMS can be particularly useful in colon obstruction in a pregnant patient with CRC because it allows solving the acute condition providing time to perform a more accurate staging study and to prepare the patient for surgery, thus reducing both post-surgical morbidity and mortality. We report on the case of a patient who early in the second trimester of pregnancy presented with an acute colonic obstruction due to CRC which was successfully managed with the placement of a self-expanding metal stent.

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

    Science.gov (United States)

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

    2014-10-01

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

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

    Science.gov (United States)

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

    2016-03-01

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

  9. Biocompatibility of a new device of self-expandable covered and non-covered tracheal stent: comparative study in rats

    Directory of Open Access Journals (Sweden)

    Olavo Ribeiro Rodrigues

    2013-01-01

    Full Text Available PURPOSE: To investigate the compatibility of a new model of self-expandable tracheal stent in rats. METHODS: A new device of polyurethane covered and non - covered stent was placed in the trachea of Wistar rats. Animals were distributed in two groups: the polyurethane covered and non-covered group. Macroscopic parameters included position within the tracheal lumen, adherence to the mucosa, degree of dilatation, permeability and internal diameter. Microscopic findings evaluated were: incorporation, inflammatory activity, granulation tissue and epithelial revetment injuries. The observation follow-up was six weeks. All parameters were quantified based on determined score values. Incorporation of the stents was evaluated based on the observation if the stent was fixed into the trachea or if it could be removed. Degree of dilatation was performed by external diameter measurements. Granulation tissue was evaluated by measurements of height of the tissue growing into the tracheal lumen. RESULTS: 100% of non-covered stents had total attachment to mucosa and 100% of polyurethane covered type had adherence only. Regarding dilatation, granulation tissue, inflammatory activity and internal diameter measurements, there were no significant differences between the groups. Pathological tracheal wall injuries were present in both groups. CONCLUSION: Both models of stent demonstrated biocompatibility with the trachea. Rats are suitable for an experimental model of tracheal stent study.

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

    Science.gov (United States)

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

    2018-02-01

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

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

    Science.gov (United States)

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

    2014-08-01

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

  12. Stent insertion in patients with malignant biliary obstruction: problems of the Hanaro stent

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jae Hyun; Seong, Chang Kyu; Shin, Tae Beom; Kim, Yong Joo [School of Medicine, Kyungpook National Univ., Daegu (Korea, Republic of); Jung, Gyoo Sik [School of Medicine, Kosin National Univ., Pusan (Korea, Republic of); Park, Byeung Ho [School of Medicine, Donga National Univ., Pusan (Korea, Republic of)

    2002-07-01

    To investigate the problems of the Hanaro stent (Solco Intermed, Seoul, Korea) when used in the palliative treatment of patients with inoperable malignant biliary obstruction. Between January 2000 and May 2001, the treatment of 46 patients with malignant biliary obstruction involved percutaneous placement of the Hanaro stent. Five patients encountered problems during removal of the stent's introduction system. The causes of obstruction were pancreatic carcinoma (n=2), cholangiocarcinoma (n=2), and gastric carcinoma with biliary invasion (n=1). In one patient, percutaneous transhepatic cholangiography and stent insertion were performed as a one-step procedure, while the others underwent conventional percutaneous transhepatic biliary drainage for at least two days prior to stent insertion. A self-expandable Hanaro stent, 8-10 mm in deameter and 50-100 mm in lengh, and made from a strand of nitinol wire, was used in all cases. Among the five patients who encountered problems, breakage of the olive tip occourred in three, upward displacement of the stent in two, and improper expansion of the distal portion of the stent, unrelated with the obstruction site, in one. The broken olive tip was pushed to the duodenum in two cases and to the peripheral intrahepatic duct in one. Where the stent migrated during withdrawal of its introduction system, an additional stent was inserted. In one case, the migrated stent was positioned near the liver capsule and the drainage catheter could not be removed. Although the number of patients in this study was limited, some difficulties were encountered in withdrawing the stent's introduction system. To prevent the occurrence of this unusual complication, the stent should be appropriately expansile, and shape in the olive tip should be considered.

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

    Science.gov (United States)

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

    2011-02-01

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

  14. Self-expandable medical memorial metallic stent with 125I seeds for the treatment of esophageal carcinoma: a retrospective analysis

    International Nuclear Information System (INIS)

    Zhang Shuo; Lu Bin

    2011-01-01

    Objective: To discuss the curative effect and safety of the implantation of self-expandable medical memorial metallic stent with 125 I seeds for the treatment of advanced esophageal carcinomas. Methods: Implantation of self-expandable medical memorial metallic stent with 125 I seeds was performed in 32 patients with advanced esophageal canner. The clinical data were retrospectively analyzed. The technical success rate, the operation time, the immediate and mid-term effectiveness, the survival time, the complications, the body weight, the blood picture, the immune indexes, the average hospitalization days and hospitalization expenses were analyzed. Results: The average operation time was (18±5) minutes. Successful stent implantation was achieved in all 32 patients (100%). No 125 I seeds fell off during the procedure. The remission rate of dysphagia was 100%. Esophageal restenosis occurred in four patients, and displacement of the stent was seed in one patient. One month after the treatment, 90% of patients had a Karnofsky performance score over 60. The mean survival time was (8.7±6.6) months. The average hospitalization time was (7.8±3.7) days and the mean hospitalization cost was (12±3) thousand Chinese Yuan. Conclusion: For the treatment of esophageal carcinomas, the implantation of self-expandable medical memorial metallic stent with 125 I seeds is safe, effective and simple. This treatment can markedly improve the symptom of dysphagia and significantly prolong the patient's survival time. (authors)

  15. New treatment of iliac artery disease: focus on the Absolute Pro® Vascular Self-Expanding Stent System

    Directory of Open Access Journals (Sweden)

    Gates L

    2013-09-01

    Full Text Available Lindsay Gates, Jeffrey Indes Vascular and Endovascular Surgery, Yale University School of Medicine, New Haven, CT, USA Abstract: Management of iliac artery disease has evolved over the years, from a surgical-only approach to a primarily endovascular-only approach as the first line treatment option. This has been continuously improved upon with the advent of new devices and applied technologies. Most recently in particular, the literature has shown good, reliable outcomes with the use of self-expandable stents in iliac artery atherosclerotic lesions. Nevertheless, no device is without its limitations, and the Absolute Pro® Vascular Self-Expanding Stent System was designed with the intent of overcoming some of the shortcomings of other available stents while maintaining acceptable postprocedural outcomes. Based on preliminary industry-acquired data, it has achieved these goals and appears to be an emergent competitor for the treatment of both focal and complex iliac artery lesions. Keywords: Absolute-Pro®, iliac stent, self-expanding stents, atherosclerotic disease

  16. Outcome of self-expanding metal stenting followed by radiation therapy for unresectable extrahepatic bile duct cancer

    International Nuclear Information System (INIS)

    Jin Jing; Gao Li; Yu Zihao; Han Jianzhu; Zhai Renyou

    2007-01-01

    Objective: To retrospectively analyze the efficacy for self-expanding metal stenting followed by radiation therapy for unresectable extrahepatic bile duct cancer. Methods: From Jan 1996 to Sep 2002, 17 patients were treated with self-expanding metal stenting followed by Ir 192 high dose brachytherapy (brachytherapy group, n=5)and by external beam radiation therapy(external radiation therapy group, n=9). Brachytherapy was delivered on the same day or the following day after stenting with the total dose of DT 20- 30 Gy, twice daily, for 2-3 days. The median total dosage of external radiation therapy was 48 Gy (14-66 Gy), 2 Gy/fraction. Results: Jaundice was released after metal stenting from 71.4% to 14.3% (P=0.001), showing no significant difference between brachytherapy and external radiation therapy in terms of jaundice release(χ 2 =0.21, P=0.65). The median survival period(5-35 months)for whole groups was 12 months 1-, 2-year survival rates were 40.8% and 8.16%, respectively. No significant difference was shown for patients received either brachytherapy or external radiation therapy for 8 months, but with 1,2 year survival rate as 40.0%, 13.3%, respectively (χ 2 =1.10, P=0.29). Conclusions: Self-expanding metal stenting is able to release jaundice significantly and followed by high dose radiation therapy may further prolong the survival. (authors)

  17. Silicone covered vs. Non- covered endotracheal self expandable metallic stent: An experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Do, Young Soo; Lee, Byung Hee; Kim, Soo Ah; Kim, Kie Hwan; Chin, Soo Yil; Cho, Kyung Ja; Cho, Dae Soon [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1994-10-15

    To evaluate pathologic changes of the trachea and the lung after insertion of silicone covered and non covered Gianturco stent in the trachea of dog. Silicone covered(covered) and non covered(bare) Gianturco stent, six in each, were inserted into the tracheal lumen of six consecutive dogs. After 1-10 weeks observation, the dogs were sacrificed and their tracheas and lungs were examined grossly and histopathologically. Serial chest radiographs were performed to evaluate pneumonia and stent migration every 3-5 days. Pneumonia was observed in one of bare stent group and five of covered stent group. Stent migration was noted in three of covered stent group. In bare stent group, the epithelium of the trachea was markedly thickened by hyperplasia and stent was covered by granulation tissue from 6 weeks after stent insertion. Inflammation was focal at contact site between the stent and the trachea. In covered stent group, the epithelium was denuded at multiple areas and there were multifocal squamous metaplasia of the mucosa. Inflammatory reaction of the trachea was diffuse. Inflammatory reaction was more severe and stent migration was more frequent in covered stent group. The use of covered stent in the trachea should be studied further.

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

    Science.gov (United States)

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

    2016-04-01

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

  19. Drug-Eluting Nitinol Stent Treatment of the Superficial Femoral Artery and Above-the-Knee Popliteal Artery (The Zilver PTX Single-Arm Clinical Study): A Comparison Between Diabetic and Nondiabetic Patients

    Energy Technology Data Exchange (ETDEWEB)

    Fanelli, Fabrizio, E-mail: fabrizio.fanelli@uniroma1.it [Sapienza University of Rome, Vascular and Interventional Radiology Unit, Department of Radiological Sciences (Italy); Primo, Massimiliano Di [Hopital Europeen Georges Pompidou, University Paris Descartes (France); Boatta, Emanuele [Sapienza University of Rome, Vascular and Interventional Radiology Unit, Department of Radiological Sciences (Italy); Johnston, Krystal, E-mail: kjohnston@medinst.com [MED Institute, Inc (United States); Sapoval, Marc, E-mail: marc.sapoval2@egp.aphp.fr [Hopital Europeen Georges Pompidou, University Paris Descartes (France)

    2013-10-15

    Purpose: To describe the 1-year results of drug-eluting nitinol stent placement in the femoropopliteal artery of diabetic and nondiabetic patients. Materials and Methods: All patients enrolled in this prospective, multicenter study underwent paclitaxel-eluting stent placement for de novo or restenotic lesions of the superficial femoral and/or popliteal artery. Baseline and follow-up walking impairment questionnaire (WIQ) scores, Rutherford classifications, and ankle-brachial index (ABI) measurements were obtained. Follow-up was completed at 1, 6, and 12 months. Results: There were 285 diabetic patients and 502 nondiabetic patients treated. There were no significant differences in mean lesion length or lesion calcification between patient groups. Procedural success in both treatment groups was >97 %. There were no significant differences between diabetic and nondiabetic groups in Kaplan-Meier estimates of patency, event-free survival (EFS), or freedom from target lesion revascularization (TLR) at 6 and 12 months. Both groups experienced a significant increase in ABI and WIQ values after treatment, and these improvements were sustained to 12-month follow-up; however, nondiabetic patients had significantly greater 6- and 12-month WIQ scores compared with diabetic patients. Based on covariate analysis, the only factors shown to be significant and to negatively influence patency were longer lesion length (p = 0.009), higher Rutherford classification (p = 0.02), and lack of hypertension (p = 0.02); diabetic status was not found to be a significant factor. Conclusion: Diabetic and nondiabetic patients had similar estimates of primary patency, EFS, and freedom from TLR; however, diabetic patients showed less improvement in WIQ scores compared with nondiabetic patients.

  20. A clinical evaluation of endoscopically placed self-expanding metallic stents in patients with acute large bowel obstruction

    DEFF Research Database (Denmark)

    Pommergaard, H C; Vilmann, P; Jakobsen, H L

    2009-01-01

    BACKGROUND AND AIMS: Self-expanding metallic stents (SEMS) have since 1991 established themselves as an option in the treatment of large bowel obstruction. The aim of this study was to evaluate the use of SEMS in management of acute colorectal obstructions at a Danish Surgical Gastroenterology...

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

    NARCIS (Netherlands)

    van Halsema, Emo E.; van Hooft, Jeanin E.

    2015-01-01

    AIM: To analyze the outcomes of self-expandable stent placement for benign esophageal strictures and benign esophageal leaks in the literature. METHODS: The PubMed, Embase and Cochrane databases were searched for relevant articles published between January 2000 and July 2014. Eight prospective

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

    Science.gov (United States)

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

    2017-07-15

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

  3. Utilization of self-expanding stents in the treatment of intracranial atherosclerotic disease in the distal small cerebral vessels

    International Nuclear Information System (INIS)

    Turk, Aquilla S.; Niemann, David B.; Aagaard-Kienitz, Beverly; Ahmed, Azam; Brooks, Nathaniel; Levine, Ross L.

    2007-01-01

    Previously, endovascular treatment of stenosis related to intracranial atherosclerosis (ICAD) involving arteries measuring less than 2 mm in diameter was limited. To our knowledge, there are no reports in the literature addressing stent placement for treatment of stenosis in arteries of this size. Four patients aged 33 to 80 years (mean 57.5 years) with medically refractory ICAD underwent angioplasty and stenting of small (<2 mm) distal intracerebral arteries. Vessel location and length of follow-up were anterior cerebral artery (ACA) A1 segment (5 months), ACA A2 segment (18 months), middle cerebral artery M1 segment (18 months), and posterior cerebral artery P1 segment (8 months) with vessel calibers ranging from 1.2 to 1.8 mm. Clinical and imaging follow-up ranged from 5 to 18 months. All procedures were successfully performed without complications. Follow-up out to 18 months demonstrated one vessel that went on to occlusion while the other stented vessel segments remained patent. One patient died 8 months after stenting, but the death was not related to neurological disease. The remaining patients experienced resolution of the presenting symptomatology and remained asymptomatic throughout follow-up. In this small series, stenoses of distal (<2 mm) cerebral arteries were amenable to treatment using new self-expanding stents. We safely and successfully treated four arteries smaller than 2 mm in diameter with newer self-expanding stents. All patients remained clinically asymptomatic. One stent occluded at 5 months and the others remained patent during follow-up. Longer term clinical follow-up is required to determine the durability and viability of this therapy. (orig.)

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

    Science.gov (United States)

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

    2017-09-01

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

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

    Science.gov (United States)

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

    2017-08-01

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

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

    Science.gov (United States)

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

    2017-07-01

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

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

    Science.gov (United States)

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

    2014-03-01

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

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

    Science.gov (United States)

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

    2006-07-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2015-08-01

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

  11. Retrievable Airway Stent Placement for Stoma Stricture after Anterior Mediastinal Tracheostomy: Case Report

    International Nuclear Information System (INIS)

    Hwang, Jae Yeon; Shin, Ji Hoon; Kim, Yong Hee; Song, Ho Young; Kim, Jin Hyoung; Lee, Yeoun Joo

    2013-01-01

    Anterior mediastinal tracheostomy (AMT) is performed to establish an airway after resection of advanced tumors in the cervicothoracic region. We report a case of successful placement of a covered retrievable self-expandable nitinol stent for a stoma stricture that developed after AMT in a patient with adenoid cystic carcinoma of the trachea. Two stent placements and removals, at two and three months after their initial placement, were performed due to loosening of the stents. Although we did not achieve long-term results as the patient died of massive hemorrhage, the stent placement was both feasible and safe, thus suggesting that temporary stent placement may be a valuable option for treating stoma stricture occurring after AMT.

  12. Malignant gastric outlet obstruction managed by endoscopic stenting: a prospective single-centre study

    DEFF Research Database (Denmark)

    Havemann, Maria Cecilie; Adamsen, Sven; Wøjdemann, Morten

    2008-01-01

    -to-treat principle. All patients were offered endoscopic stenting. Oral intake before and after stenting was assessed using the gastric outlet obstruction score system (GOOSS). Various lengths of duodenal Hanaro(R) self-expanding nitinol stents were delivered through a therapeutic endoscope. Outcome criteria were......Objective. Endoscopic stenting for malignant gastric outlet obstruction was chosen as the primary strategy by which to palliate this complication, which is dominated by weight loss and anorexia. Advanced upper gastrointestinal tract cancers present late and life expectancy is limited. Only smaller...... multicentre studies point to endoscopic stenting as superior to surgery in terms of clinical outcome and cost. Material and methods. Forty-five consecutive patients with gastric outlet obstruction as a result of advanced upper GI-tract malignancy were enrolled in accordance with the intention...

  13. Retrievable Airway Stent Placement for Stoma Stricture after Anterior Mediastinal Tracheostomy: Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jae Yeon; Shin, Ji Hoon; Kim, Yong Hee; Song, Ho Young; Kim, Jin Hyoung [Dept. of University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Lee, Yeoun Joo [Dept. of Pediatrics, Pusan National University Children' s Hospital, Yangsan (Korea, Republic of)

    2013-06-15

    Anterior mediastinal tracheostomy (AMT) is performed to establish an airway after resection of advanced tumors in the cervicothoracic region. We report a case of successful placement of a covered retrievable self-expandable nitinol stent for a stoma stricture that developed after AMT in a patient with adenoid cystic carcinoma of the trachea. Two stent placements and removals, at two and three months after their initial placement, were performed due to loosening of the stents. Although we did not achieve long-term results as the patient died of massive hemorrhage, the stent placement was both feasible and safe, thus suggesting that temporary stent placement may be a valuable option for treating stoma stricture occurring after AMT.

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

    Directory of Open Access Journals (Sweden)

    Kumagai Hozumi

    2012-09-01

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

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

    Science.gov (United States)

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

    2012-05-01

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

  16. In vitro stent lumen visualisation of various common and newly developed femoral artery stents using MR angiography at 1.5 and 3 tesla.

    Science.gov (United States)

    Syha, R; Ketelsen, D; Kaempf, M; Mangold, S; Sixt, S; Zeller, T; Springer, F; Schick, F; Claussen, C D; Brechtel, K

    2013-02-01

    To evaluate stent lumen assessment of various commonly used and newly developed stents for the superficial femoral artery (SFA) using MR angiography (MRA) at 1.5 and 3 T. Eleven nitinol stents and one cobalt-chromium stent were compared regarding stent lumen visualisation using a common three-dimensional MRA sequence. Maximum visible stent lumen width and contrast ratio were analysed in three representative slices for each stent type. A scoring system for lumen visualisation was applied. Nitinol stents showed significantly better performance than the cobalt chromium stent (P stent lumen ranged between 43.4 and 95.5 %, contrast ratio between 7.2 and 110.6 %. Regarding both field strengths, seven of the nitinol stents were classified as "suitable". Three nitinol stents were "limited", and one nitinol stent and the cobalt chromium stent were "not suitable". Intraluminal loss of signal and artefacts of most of the SFA stents do not markedly limit assessment of stent lumen by MRA at 1.5 and 3 T. MRA can thus be considered a valid technique for detection of relevant in-stent restenosis. Applied field strength does not strongly influence stent lumen assessment in general, but proper choice of field strength might be helpful.

  17. Thermo-expandable prostatic stents for bladder outlet obstruction in the frail and elderly population: An underutilized procedure?

    Directory of Open Access Journals (Sweden)

    Kapil Sethi

    2017-11-01

    Full Text Available Purpose: To report our outcomes with the use of a thermo-expandable metallic intraprostatic stent (Memokath for patients with bladder outlet obstruction (BOO secondary to prostatic obstruction, and to assess it is a feasible option for many frail and elderly men unsuitable for surgery. Materials and Methods: We reviewed patients who underwent insertion of a Memokath stent for BOO over 17 years (January 1999 to December 2015 at one regional center over a long follow-up period (median, 7 years. Patients were selected if they had obstructive urinary symptoms or urinary retention with an indwelling catheter in situ, and were ineligible for transurethral resection of the prostate (TURP under general or spinal anesthesia. Primary outcomes assessed were the improvement in urinary symptoms and voiding parameters, as well as the ability to void spontaneously if catheterized, along with complications. Results: One hundred forty-four patients who presented with BOO or urinary retention had a Memokath stent inserted. Ninety patients (62.5% had a successful stent insertion with a significant difference between the median preoperative (550 mL and postoperative residual volume (80 mL, p<0.0001. Nearly two-thirds of men (64% returned to unassisted voiding with no increased risk of complications over time. Fifty-four patients (37.5% experienced stent failure. Main complications requiring stent removal or repositioning were migration, occlusion, refractory urinary retention and irritative voiding symptoms. Conclusions: In elderly and frail men with BOO deemed unsuitable to undergo TURP, prostatic stent is a safe and practical alternative to long-term catheterization.

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

    Science.gov (United States)

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

    2011-10-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Løvdal, Alexandra Liv Vest, E-mail: alvlo@nanotech.dtu.dk [Technical University of Denmark, Department of Micro- and Nanotechnology (Denmark); Calve, Sarah [Purdue University, Weldon School of Biomedical Engineering (United States); Yang, Shuo; Alstine, William Van [Cook Research Incorporated (United States); Binkert, Christoph A. [Institut für Radiologie, Kantonsspital Winterthur (Switzerland); Klausen, Kasper [William Cook Europe (Denmark)

    2017-01-15

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

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

    Science.gov (United States)

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

    2017-01-01

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

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

    International Nuclear Information System (INIS)

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

    2017-01-01

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

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

    Science.gov (United States)

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

    2016-04-01

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

  4. Effectiveness and Safety of Endoscopic Treatment of Benign Biliary Strictures Using a New Fully Covered Self Expandable Metal Stent

    Directory of Open Access Journals (Sweden)

    Mihir S. Wagh

    2013-01-01

    Full Text Available Background. In patients with benign biliary strictures, the use of fully covered self-expandable metal stents (SEMS has been proposed as an alternative to plastic stenting, but high quality prospective data are sparse. This study was performed to evaluate the long-term effectiveness and safety of a new fully covered SEMS for benign biliary strictures. Methods. All consecutive patients with benign biliary strictures were treated with placement of a fully covered SEMS (WallFlex for 6 months. Short- and long-term stricture resolution, adverse events, and ease of stent removal were recorded. Results. 23 patients were enrolled. Stricture etiology was chronic pancreatitis (14, postorthotopic liver transplant (4, idiopathic (4, and biliary stones (1. All ERCPs were technically successful. All stents were successfully removed. Short-term stricture resolution was seen in 22/23 (96% patients. Long-term success was 15/18 (83.3%. All 3 failures were patients with biliary strictures in the setting of chronic calcific pancreatitis. Conclusions. The use of the new SEMS for the treatment of benign biliary strictures led to short-term stricture resolution in the vast majority of patients. Over a long-term followup the success rate appears favorable compared to historical results achieved with multiple plastic stenting, particularly in patients with chronic pancreatitis. The study was registered with ClinicalTrials.gov (NCT01238900.

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

    Science.gov (United States)

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

    2008-11-01

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

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

    Science.gov (United States)

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

    2016-09-01

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

  7. Treatment of symptomatic high-grade intracranial stenoses with the balloon-expandable Pharos stent: initial experience

    International Nuclear Information System (INIS)

    Kurre, W.; Berkefeld, J.; Mesnil de Rochemont, R. du; Sitzer, M.; Neumann-Haefelin, T.

    2008-01-01

    We report our first clinical experience with a CE-marked flexible monorail balloon-expandable stent for treatment of high-grade intracranial stenoses. Between April 2006 and November 2007 21 patients with symptomatic intracranial stenoses (>70%) were treated with the PHAROS stent. In seven patients, the procedure was performed during acute stroke intervention. Procedural success, clinical complication rates and mid-term follow-up data were prospectively recorded. During a median follow-up period of 7.3 months one additional patient died of an unknown cause 3 months after the intervention. A patient with a significant residual stenosis presented with a new stroke after further progression of the residual stenosis. None of the successfully treated patients experienced ipsilateral stroke. Recanalization of intracranial stenoses with the balloon-expandable Pharos stent is technically feasible. The periprocedural complication rate and mid-term follow-up results were in the range of previously reported case series. This pilot study was limited by the small sample size and severe morbidity of the included patients. Final evaluation of the efficacy of Pharos stent treatment demands further investigation. (orig.)

  8. Insertion of a self-expandable endotracheal metal stent using topical anaesthesia and a fibreoptic bronchoscope: a comfortable way to offer palliation.

    OpenAIRE

    Coolen, D.; Slabbynck, H.; Galdermans, D.; Van Schaardenburg, C.; Mortelmans, L. L.

    1994-01-01

    A self-expandable stent was used to obtain prolonged relief of stridor resulting from tracheal obstruction by extrinsic tumour compression despite prior external irradiation. The stent was inserted in an easy and comfortable procedure with fibreoptic bronchoscopy under local anaesthesia.

  9. MRT of carotid stents: influence of stent properties and sequence parameters on visualization of the carotid artery lumen

    International Nuclear Information System (INIS)

    Straube, T.; Wolf, S.; Alfke, K.; Jansen, O.; Flesser, A.; Deli, M.; Nabavi, A.

    2005-01-01

    Purpose: To evaluate MR artifacts of carotid artery stents and to optimize stent properties and sequence parameters. Material and Methods: Four carotid artery stents - Wallstent (mediloy), Precise (nitinol), ACCULINK (nitinol) and a stent prototype (nitinol) - were investigated in a flow model of the cervical vessels. The model was made of silicon tubing and a flow pump that produces realistic flow curves of the carotid artery. To investigate the effects of magnetic susceptibility and radiofrequency induced shielding artifacts, turbo spin echo and gradient echo sequences as well as CE-MRAs were measured. To improve the visualization of the stent lumen in a CE-MRA, flip angle as well as geometry and covering of the stent prototype were altered. Results: Susceptibility artifacts in stents of the carotid artery only influence the lumen visualization at the proximal and distal end of the braided mediloy stent. A change of stent coverings has no significant influence on radiofrequency artifacts, whereas a reduction in linking elements between stent segments and a change in diameter of stent struts improves visualization of the stent lumen. By increasing the flip angle in a CE-MRA, visualization of the stent lumen is possible in both mediloy and nitinol stents. Conclusion: The choice of stent material and changes in stent geometry as well as the optimization of the flip angle of the CE-MRA may reduce susceptibility and radiofrequency artifacts, rendering feasible the CE-MRA of a stented carotid artery. (orig.)

  10. Transjugular Intrahepatic Portosystemic Shunt Flow Reduction with Adjustable Polytetrafluoroethylene-Covered Balloon-Expandable Stents Using the “Sheath Control” Technique

    Energy Technology Data Exchange (ETDEWEB)

    Blue, Robert C., E-mail: Robert.c.blue@gmail.com; Lo, Grace C.; Kim, Edward; Patel, Rahul S.; Scott Nowakowski, F.; Lookstein, Robert A.; Fischman, Aaron M. [Icahn School of Medicine at Mount Sinai, Interventional Radiology Section, Department of Radiology (United States)

    2016-06-15

    PurposeA complication of transjugular intrahepatic portosystemic shunts (TIPS) placement is refractory portosystemic encephalopathy (PSE) often requiring TIPS reduction. We report the results of a “sheath control technique” utilizing constraining sheaths during deployment of polytetrafluoroethylene (PTFE)-covered balloon-expandable stents, minimizing stent migration, and providing additional procedural control.MethodsTIPS reduction was performed in 10 consecutive patients for PSE using Atrium iCast covered stents (Atrium Maquet Getinge Group, Germany). Within the indwelling TIPS stent, a 9 mm × 59 mm iCast stent was deployed with 2 cm exposed from the sheath’s distal end and the majority of the stent within the sheath to create the distal hourglass shape. During balloon retraction, the stent was buttressed by the sheath. The proximal portion of the stent was angioplastied to complete the hourglass configuration, and the central portion of the stent was dilated to 5 mm. Demographics, pre- and post-procedure laboratory values, and outcomes were recorded.ResultsTen patients underwent TIPS reduction with 100 % technical success. There was no stent migration during stent deployment. All patients experienced initial improvement of encephalopathy. One patient ultimately required complete TIPS occlusion for refractory PSE, and another developed TIPS occlusion 36 days post-procedure. There was no significant trend toward change in patients’ MELD scores immediately post-procedure or at 30 days (p = 0.46, p = 0.47, respectively).ConclusionTIPS reduction using Atrium iCast PTFE balloon-expandable stents using the “sheath control technique” is safe and effective, and minimizes the risk of stent migration.

  11. Role of fluoroscopic guided self expandable metallic stents in the management of malignant esophageal strictures

    Directory of Open Access Journals (Sweden)

    Mohamed Shaker

    2016-09-01

    Conclusion: Fluoroscopic guided esophageal stenting is a highly effective and safe method for palliating dysphagia in patients with obstructing esophageal cancer with significant clinical improvement.

  12. Fatal complication from a balloon-expandable tracheal stent in a child: a case report.

    Science.gov (United States)

    Stotz, William H; Berkowitz, Ivor D; Hoehner, Jeff C; Tunkel, David E

    2003-01-01

    The use of airway stents in the pediatric population is uncommon, reflected in the few patient series reported in the literature. We describe a fatal complication of tracheal stent placement in an 18-month-old child with spondylothoracic dysplasia. Case report. Intensive care unit of a tertiary academic pediatric center. An 18-month-old child with spondylothoracic dysplasia who underwent tracheal stent placement for tracheomalacia. Management of an acute upper-airway hemorrhage. The patient died, despite aggressive interventions. Use of tracheal stents in pediatric patients with tracheomalacia is not without risks; tracheal erosion with severe hemoptysis is an infrequent but devastating complication of this intervention.

  13. Stent-Assisted Coil Embolization of a Mycotic Renal Artery Aneurysm by Use of a Self-Expanding Neurointerventional Stent

    International Nuclear Information System (INIS)

    Rabellino, Martin; García-Nielsen, Luis; Zander, Tobias; Baldi, Sebastián; Llorens, Rafael; Maynar, Manuel

    2011-01-01

    Mycotic aneurysms are uncommon, especially those located in visceral arteries. We present a case of a patient with two visceral mycotic aneurysms due to bacterial endocarditis, one located in right upper pole renal artery and the second in the splenic artery. Both aneurysms were treated as endovascular embolization using microcoils. In the aneurysm located at the renal artery, the technique of stent-assisted coils embolization was preferred to avoid coils migration due to its wide neck. The stent used was the Solitaire AB, which was designed for the treatment of intracranial aneurysms and was used recently in acute stroke as a mechanical thrombectomy device. Complete embolization of the aneurysm was achieved, preserving all the arterial branches without nephrogram defects in the final angiogram.

  14. Self-expandable covered metallic esophageal stent impregnated with beta-emitting radionuclide: an experimental study in canine esophagus

    International Nuclear Information System (INIS)

    Won, Je Hwan; Lee, Jong Doo; Wang, Hee Jung; Kim, Gui-Eon; Kim, Bong Wan; Yim, Hyunee; Han, Sang Keon; Park, Chan H.; Joh, Chul Woo; Kim, Kyung-Hwa; Park, Kyung Bae; Shin, Kyong-Min

    2002-01-01

    Purpose: A specially designed self-expandable covered metallic stent impregnated with the β-emitting radioisotope 166 Ho ( 166 Ho, energy: 1.85 and 1.76 MeV, T((1)/(2)): 26.8 h) was developed at our institute for the purpose of intraluminal palliative brachytherapy, as well as for treating malignant esophageal stricture and swallowing difficulty. The aim of this study was to evaluate the tissue response to brachytherapy and the safety of the radioactive metallic stent with regard to the normal canine esophagus before clinical application. Methods and Materials: 166 Ho was impregnated into the polyurethane membrane (50 μ thickness) covering the outer surface of a self-expandable metallic stent (diameter, 18 mm; length, 40 mm). Stents with radioactivity 4.0-7.8 mCi (Group A, n=15), 1.0-1.8 mCi (Group B, n 5), and 0.5-0.7 mCi (Group C, n=5) were placed in the esophagi of 25 healthy beagle dogs, and the stents were tightly anchored surgically to prevent migration. The estimated radiation dose calculated by Monte Carlo simulation was 194-383 Gy in Group A, 48-90 Gy in Group B, and 23-32 Gy in Group C. The dogs were killed 8-12 weeks after insertion of the stents, and histologic examinations of the esophageal walls were performed. Results: In Group A, 3 of 15 dogs died of wound infection, so specimens were obtained from only 12 dogs; all 12 cases showed esophageal stricture with mucosal ulceration. Microscopically, severe fibrosis and degeneration of the muscular propria were found in 3 dogs, complete fibrosis of the entire esophageal wall was found in 7 dogs, and esophageal fibrosis with radiation damage within periesophageal soft tissue was found in 2 dogs. However, esophageal perforation did not develop, despite extremely high radiation doses. In Group B, glandular atrophy and submucosal fibrosis were found, but the muscular layer was intact. In Group C, no histologic change was found in 3 dogs, but submucosal inflammation and glandular atrophy with intact mucosa

  15. Implantation of modified Y-shaped self-expandable stent for the treatment of stenosis of gastroenteric stoma: preliminary results in five cases

    International Nuclear Information System (INIS)

    Wu Gang; Si Jiangtao; Han Xinwei; Jiao Dechao; Ding Pengxu; Fu Mingti; Li Zhen; Ma Ji

    2010-01-01

    Objective To investigate the feasibility and therapeutic effect of stenting therapy by using modified Y-shaped self-expandable metal stent for the stenosis of gastroenteric stoma. Methods: According to the particular anatomic structures and the pathological features of the narrowed gastroenteric stoma,the authors designed a modified Y-shaped self-expandable metal stent. Under the fluoroscopic guidance, implantation of modified Y-shaped self-expandable metal stent was performed in 5 patients with narrowed gastroenteric stoma. The technical safety and the clinical results were evaluated. Results: The modified Y-shaped self-expandable metal stent was successfully implanted with one procedure in all five patients. After the implantation the symptoms such as nausea, vomiting, abdominal distension were promptly relieved, and the patients' living quality was markedly improved. Conclusion: The stenting therapy with modified Y-shaped self-expandable metal stent can rapidly relieve the stenosis of gastroenteric stoma once for all. The technique is feasible and the short-term effect is reliable, therefore, it is worth popularizing this therapy in clinical practice. (authors)

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

    DEFF Research Database (Denmark)

    Løvdal, Alexandra Liv Vest; Calve, Sarah; Yang, Shuo

    2017-01-01

    implants each for 2 and 3½ weeks, respectively. Results  In vitro the stent-base showed an elliptical deformation but no fractures. In vivo the stent-base showed adequate radial force and no migration. All implanted stent-bases showed multiple fractures not only at the predicted stress zones but at all......  A bioabsorbable self-expandable stent-base made from PLLA for large veins seems feasible, but over time, the PLLA used in this study appears too stiff and lacks the sufficient flexibility to move with the vena cava, causing multiple fractures....

  17. Reversal of Transjugular Intrahepatic Portosystemic Shunt (TIPS)-Induced Hepatic Encephalopathy Using a Strictured Self-Expanding Covered Stent

    International Nuclear Information System (INIS)

    Cox, Mitchell W.; Soltes, George D.; Lin, Peter H.; Bush, Ruth L.; Lumsden, Alan B.

    2003-01-01

    Hepatic encephalopathy is a known complication following percutaneous transjugular intrahepatic portosystemic shunt (TIPS) placement. We describe herein a simple and effective strategy of TIPS revision by creating an intraluminal stricture within a self-expanding covered stent, which is deployed in the portosystemic shunt to reduce the TIPS blood flow. This technique was successful in reversing a TIPS-induced hepatic encephalopathy in our patient

  18. Temporary self-expanding cardia stents for the treatment of achalasia: an experimental study in dogs

    International Nuclear Information System (INIS)

    Zhu Yueqi; Cheng Yingsheng; Li Minghua; Zhao Jungong; Li Feng; Chen Niwei

    2011-01-01

    Objective: To assess the performance, efficiency and optimal removal time of a newly designed temporary retrievable cardia covered stent (TRC-CS) for the treatment of achalasia in a dog model. Methods: Eighty-four achalasia-like dog models were randomly divided into seven groups of 12, a control group (CG; no stent insertion), a standard stent control group (NSCG, standard esophageal stent) and five treatment groups (TG, TRC-CS). Stents were retrieved at 4 days after insertion in the NSCG and at 4 days (4 d-TG), 2 weeks (2 w-TG), 1 month (1 m-TG), 3 months (3 m-TG), and 6 months (6 m-TG) in the TGs. lower esophageal sphincter pressure (LESP) and a timed barium esophagram were assessed before stent insertion, after stent retrieval, and at 1-week, 1-, 3- and 6-month follow-up. Three dogs in NSCG and 4 d-TG were sacrificed for histological examination at each follow-up to investigate the inflammatory reaction after stent insertion. Results: Stent insertion/removal and the follow-up procedures were well tolerated. At 6-month follow-up, the 2 w-TG and 1 m-TG demonstrated an acceptable stent migration (n=2 in both TGs versus n=4 in NSCG, n=4 in 3 m-TG, and =6 in 6 m-TG), improved LESP compared to after BAC injection (P<0.05), and improved timed barium height (p=0.0144 and 0.0409). Mouse-proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin staining revealed no inflammatory reaction difference between the NSCG and 4d-TG at each follow-up. Conclusion: The TRC-CS was effective in the treatment of achalasia in a dog model. LESP measurements, timed barium esophagram studies suggest an optimal stent retrieval time of between 2 w∼1 m. (authors)

  19. Membranous obstruction of inferior vena cava(MOIVC): treatment with percutaneous transluminal angioplasty(PTA) and self expandable metallic stent

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ki Yeol; Kim, Baek Hyun; Cha, In Ho; Lee, Nam Joon; Kim, Yun Hwan; Kim, Jung Hyuk [College of Medicine, Korea University, Seoul (Korea, Republic of)

    1994-03-15

    Percutaneous transluminal angioplasty(PTA) with a balloon catheter is a standard method of treatment for membranous obstruction of inferior vena cava(MOIVC). But, correct therapeutic approach has not been established for MOIVC patients whose lesion is associated with extensive thrombotic IVC occlusion. We tried to treat MOIVC associated with or without thrombus. We treated 13 cases of MOIVC(associated with thrombus in 7 cases, no thrombus in 6 cases) with PTA, thrombolysis and self-expandable metallic stents. PTA was successful in 8 cases, but failed in 5 cases. The recurred cases were retreated with PTA, but follow-up study revealed recoiling restenosis in 4 cases and intimal hyperplasia in 1 case at previous PTA site which could be overcome with a self-expandable metallic stent. The complication were occurred in 3 cases which were hemothorax, hemopericardium, and hemoperitoneum respectively. However, those were resolved by conservative treatment only. Recanalization and dilatation could be done in MOIVC patients with or without thrombosis for improvement of patient's symptom. Gianturco self-expandable metallic stent is useful in treatment of recurred MOIVC after balloon dilatation and preventing reocclusion of the IVC after PTA.

  20. Covered self-expandable metal stents in pancreatic malignancy regardless of resectability: a new concept validated by a decision analysis.

    Science.gov (United States)

    Kahaleh, M; Brock, A; Conaway, M R; Shami, V M; Dumonceau, J M; Northup, P G; Tokar, J; Rich, T A; Adams, R B; Yeaton, P

    2007-04-01

    The current treatment model for the management of malignant biliary obstruction is to place a plastic stent for unstaged pancreatic cancer. In patients with unresectable disease but a life expectancy of more than 6 months, self-expandable metal stents (SEMS) are favored because of their more prolonged patency. We analyzed the efficacy and cost-effectiveness of covered SEMS (CSEMS) in patients with pancreatic cancer and distal biliary obstruction without regard to surgical resectability. Between March 2001 and March 2005, 101 consecutive patients with obstructive jaundice secondary to pancreatic cancer underwent placement of a CSEMS. Patients with resectable tumor were offered pancreaticoduodenectomy. A model was developed to compare the costs of CSEMS and polyethylene and DoubleLayer stents. A total of 21 patients underwent staging laparoscopy, of whom 16 had a resection (76%). The 85 patients who did not have a resection had a mean survival of 5.9 months (range 1-25 months) and a mean CSEMS patency duration of 5.5 months (range 1-16 months). Life-table analysis demonstrated CSEMS patency rates of 97% at 3 months, 85% at 6 months, and 68% at 12 months. In a cost model that accounted for polyethylene and DoubleLayer stent malfunction and surgical resections, initial CSEMS placement (3177 euros per patient) was a less costly intervention than either DoubleLayer stent placement (3224 euros per patient) or polyethylene stent placement with revision (3570 euros per patient). Covered SEMS are an effective treatment for distal biliary obstructions caused by pancreatic carcinoma. Their prolonged patency and removability makes them an attractive option for biliary decompression, regardless of resectability. The strategy of initial covered SEMS placement might be the most cost-effective strategy in these patients.

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

    Science.gov (United States)

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

    2017-01-01

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

  2. Management of acute malignant colorectal obstruction with a novel self-expanding metallic stent as a bridge to surgery

    International Nuclear Information System (INIS)

    Li Yongdong; Cheng Yingsheng; Li Minghua; Fan Youben; Chen Niwei; Wang Yu; Zhao Jungong

    2010-01-01

    Purpose: To prospectively evaluate the safety and clinical efficacy of a newly designed self-expandable metallic stent (SEMS) in the treatment of patients with acute malignant colorectal obstruction. Methods: Between April 2001 and October 2007, 52 patients with acute malignant colorectal obstruction were treated with a new designed SEMS as an investigational bridge to surgery. Patients were prospectively followed and relevant data collection was collected, including details regarding technique, clinical symptoms, complications, need for elective surgery, and overall survival. Results: Stent placement was technically successful in all but two patients (due to complete obstruction) with no procedure-related complications. Complications included stent migration (n = 4), anal pain (n = 2) and stool impaction (n = 1). Clinical success was achieved in 49 (98%) of 50 patients with resolution of bowel obstruction within 2 days of stent placement. In one patient with stool impaction 2 days after stent placement, endoscopic disimpaction was successfully performed. An elective one-stage surgical procedure was performed in all 50 patients who successfully received a SEMS as a bridge to surgery within a mean of 8 ± 2 days (range: 4-11 days) after stent placement. Mean follow-up time was 36 ± 12 months (range 3-70 months), and all patients remained alive at the time of this report. Conclusion: The newly designed SEMS placement as a bridge to surgery was a safe and effective intervention for colonic decompression in patients with acute malignant colorectal obstruction and allowed a high proportion of patients to be successfully proceeded to elective surgery.

  3. Impact of Carcinomatosis on Clinical Outcomes after Self-Expandable Metallic Stent Placement for Malignant Gastric Outlet Obstruction.

    Directory of Open Access Journals (Sweden)

    Ji Eun Lee

    Full Text Available It is still unclear whether the peritoneal carcinomatosis had a negative effect on the clinical outcomes of patients who underwent self-expandable metallic stent (SEMS placement for malignant gastric outlet obstruction (GOO. Although carcinomatosis may be associated with the development of multifocal gastrointestinal (GI tract obstruction or decreased bowel movement, previous studies investigated the occurrence of stent failure only and thus had limitation in evaluating clinical outcomes of patients with carcinomatosis.Between 2009 and 2013, 155 patients (88 patients without carcinomatosis and 67 patients with carcinomatosis underwent endoscopic SEMS placement for malignant GOO. Factors affecting clinical success and obstructive symptom-free survival (time period between SEMS placement and the recurrence of obstructive symptoms due to multifocal GI tract obstruction or decreased bowel movement as well as stent failure were assessed.Patients with carcinomatosis showed higher Eastern Cooperative Oncology Group (ECOG scale than those without carcinomatosis. Clinical success rates were 88.1% in patients with carcinomatosis and 97.7% in patients without carcinomatosis. In multivariate analysis, only ECOG scale was identified as an independent predictor of clinical success. During follow-up period, patients with carcinomatosis showed significantly shorter obstructive symptom-free survival than those without carcinomatosis. In multivariate analysis, the presence of carcinomatosis, chemotherapy or radiation therapy after SEMS placement, and obstruction site were identified as independent predictors of obstructive symptom-free survival. For patient without carcinomatosis, stent failure accounted for the recurrence of obstructive symptoms in 84.6% of cases. For patients with carcinomatosis, multifocal GI tract obstruction or decreased bowel movement accounted for 37.9% of cases with obstructive symptom recurrence and stent failure accounted for 44.8% of

  4. Management of acute malignant colorectal obstruction with a novel self-expanding metallic stent as a bridge to surgery

    Energy Technology Data Exchange (ETDEWEB)

    Li Yongdong [Department of Radiology and Research Institute of Radiology, Sixth Affiliated People' s Hospital, Shanghai Jiao Tong University, No. 600, Yi Shan Road, Shanghai 200233 (China); Cheng Yingsheng [Department of Radiology and Research Institute of Radiology, Sixth Affiliated People' s Hospital, Shanghai Jiao Tong University, No. 600, Yi Shan Road, Shanghai 200233 (China); Department of Radiology, Tenth Affiliated People' s Hospital, Shanghai Tong Ji University, No. 301, Middle Yan Chang Road, Shanghai 200072 (China)], E-mail: chengys@sh163.net; Li Minghua [Department of Radiology and Research Institute of Radiology, Sixth Affiliated People' s Hospital, Shanghai Jiao Tong University, No. 600, Yi Shan Road, Shanghai 200233 (China); Fan Youben; Chen Niwei; Wang Yu [Department of Gastroenterology, Sixth Affiliated People' s Hospital, Shanghai Jiao Tong University (China); Zhao Jungong [Department of Radiology and Research Institute of Radiology, Sixth Affiliated People' s Hospital, Shanghai Jiao Tong University, No. 600, Yi Shan Road, Shanghai 200233 (China)

    2010-03-15

    Purpose: To prospectively evaluate the safety and clinical efficacy of a newly designed self-expandable metallic stent (SEMS) in the treatment of patients with acute malignant colorectal obstruction. Methods: Between April 2001 and October 2007, 52 patients with acute malignant colorectal obstruction were treated with a new designed SEMS as an investigational bridge to surgery. Patients were prospectively followed and relevant data collection was collected, including details regarding technique, clinical symptoms, complications, need for elective surgery, and overall survival. Results: Stent placement was technically successful in all but two patients (due to complete obstruction) with no procedure-related complications. Complications included stent migration (n = 4), anal pain (n = 2) and stool impaction (n = 1). Clinical success was achieved in 49 (98%) of 50 patients with resolution of bowel obstruction within 2 days of stent placement. In one patient with stool impaction 2 days after stent placement, endoscopic disimpaction was successfully performed. An elective one-stage surgical procedure was performed in all 50 patients who successfully received a SEMS as a bridge to surgery within a mean of 8 {+-} 2 days (range: 4-11 days) after stent placement. Mean follow-up time was 36 {+-} 12 months (range 3-70 months), and all patients remained alive at the time of this report. Conclusion: The newly designed SEMS placement as a bridge to surgery was a safe and effective intervention for colonic decompression in patients with acute malignant colorectal obstruction and allowed a high proportion of patients to be successfully proceeded to elective surgery.

  5. MR Angiography of Peripheral Arterial Stents: In Vitro Evaluation of 22 Different Stent Types

    Directory of Open Access Journals (Sweden)

    Matthias C. Burg

    2011-01-01

    Full Text Available Purpose. To evaluate stent lumen visibility of a large sample of different peripheral arterial (iliac, renal, carotid stents using magnetic resonance angiography in vitro. Materials and Methods. 21 different stents and one stentgraft (10 nitinol, 7 316L, 2 tantalum, 1 cobalt superalloy, 1 PET + cobalt superalloy, and 1 platinum alloy were examined in a vessel phantom (vessel diameters ranging from 5 to 13 mm filled with a solution of Gd-DTPA. Stents were imaged at 1.5 Tesla using a T1-weighted 3D spoiled gradient-echo sequence. Image analysis was performed measuring three categories: Signal intensity in the stent lumen, lumen visibility of the stented lumen, and homogeneity of the stented lumen. The results were classified using a 3-point scale (good, intermediate, and poor results. Results. 7 stents showed good MR lumen visibility (4x nitinol, 2x tantalum, and 1x cobalt superalloy. 9 stents showed intermediate results (5x nitinol, 2x 316L, 1x PET + cobalt superalloy, and 1x platinum alloy and 6 stents showed poor results (1x nitinol, and 5x 316L. Conclusion. Stent lumen visibility varies depending on the stent material and type. Some products show good lumen visibility which may allow the detection of stenoses inside the lumen, while other products cause artifacts which prevent reliable evaluation of the stent lumen with this technique.

  6. Collapse of the balloon-expandable stent in the common iliac artery due to minor external compression in a lean patient

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Eun; Choi, Ho Cheol; Choi, Dae Seob; Lee, Sang Min; Lee, Jung Eun [Gyeongsang National University School of Medicine and Gyeongsang National University Hospital, Jinju (Korea, Republic of); Cho, Su Beom; Ahn, Jong Hwa [Gyeongsang National University School of Medicine and Gyeongsang National University Changwon Hospital, Changwon (Korea, Republic of)

    2017-08-15

    A 60-year-old lean man with claudication due to severe stenosis of the right common iliac artery (CIA) underwent balloon-expandable stent deployment. Nineteen months later, claudication and lower limb ischemia in the patient recurred after minor external pressure and computed tomography indicated collapse of the right CIA stent. We performed balloon angioplasty again and self-expandable stent deployment was performed, and the patient's symptoms were relieved. We suggest that the CIA in a lean person could be susceptible to external pressure.

  7. Collapse of the balloon-expandable stent in the common iliac artery due to minor external compression in a lean patient

    International Nuclear Information System (INIS)

    Park, Sung Eun; Choi, Ho Cheol; Choi, Dae Seob; Lee, Sang Min; Lee, Jung Eun; Cho, Su Beom; Ahn, Jong Hwa

    2017-01-01

    A 60-year-old lean man with claudication due to severe stenosis of the right common iliac artery (CIA) underwent balloon-expandable stent deployment. Nineteen months later, claudication and lower limb ischemia in the patient recurred after minor external pressure and computed tomography indicated collapse of the right CIA stent. We performed balloon angioplasty again and self-expandable stent deployment was performed, and the patient's symptoms were relieved. We suggest that the CIA in a lean person could be susceptible to external pressure

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

    Science.gov (United States)

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

    1997-12-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

  10. Clinical application of self-expanding metallic stent in the management of acute left-sided colorectal malignant obstruction

    Institute of Scientific and Technical Information of China (English)

    You-Ben Fan; Ying-Sheng Cheng; Ni-Wei Chen; Hui-Min Xu; Zhe Yang; Yue Wang; Yu-Yao Huang; Qi Zheng

    2006-01-01

    AIM: To summarize our experience with the application of self-expanding metallic stent (SEMS) in the management of acute left-sided colorectal malignant obstruction.METHODS: A retrospective chart review of all patients undergoing placement of SEMS between April 2000 and January 2004 was performed.RESULTS: Insertion of SEMS was attempted in 26patients under fluoroscopic guidance with occasional endoscopic assistance. The sites of lesions were located in splenic flexure of two patients, left colon of seven patients, sigmoid colon of eight patients and rectum of nine patients. The intended uses of SEMS were for palliation in 7 patients and as a bridge to elective surgery in 19 patients. In the latter group, placement of SEMS allowed for preoperative systemic and bowel preparation and the following one-stage anastomosis. Successful stent placement was achieved in 22 (85%) of the 26patients. The clinical bowel obstruction resolved 24 hours after successful stent placement in 21 (95%) patients.Three SEMS-related minor complications occurred, two stents migrated and one caused anal pain.CONCLUSION: SEMS represents an effective and safe tool in the management of acute malignant colorectal obstruction. As a bridge to surgery, SEMS can provide time for systematic support and bowel preparation and obviate the need for fecal diversion or on-table lavage.As a palliative measure, SEMS can eliminate the need for emergent colostomy.

  11. Simon-nitinol filter

    International Nuclear Information System (INIS)

    Simon, M.; Kim, D.; Porter, D.H.; Kleshinski, S.

    1989-01-01

    This paper discusses a filter that exploits the thermal shape-memory properties of the nitinol alloy to achieve an optimized filter shape and a fine-bore introducer. Experimental methods and materials are given and results are analyzed

  12. Novo modelo de endoprótese traqueal autoexpansível de fabricação nacional: estudo experimental em coelhos A new model of a self-expanding tracheal stent made in Brazil: an experimental study in rabbits

    Directory of Open Access Journals (Sweden)

    Celso Murilo Nálio Matias de Faria

    2012-04-01

    Full Text Available Objetivamos testar um novo modelo de endoprótese traqueal autoexpansível para que esse possa ser futuramente disponibilizado para o uso clínico. As endopróteses de nitinol revestidas de poliuretano foram alocadas no terço médio da traqueia de 25 coelhos da raça Nova Zelândia sob laringoscopia direta. Após um período de observação médio de 26 dias, avaliou-se a migração da prótese, grau de dilatação, incorporação, aderência, formação de tecido de granulação, presença de infiltrado inflamatório, envolvimento parietal e revestimento epitelial. Os resultados demonstraram completa expansibilidade radial, pouca aderência à mucosa traqueal e baixa incorporação tecidual, assim como alta taxas de formação de granulomas e de migração. Esse novo modelo demonstrou ser biocompatível e teve comportamento semelhante ao de outras próteses disponíveis no mercado.We aimed to test a new model of self-expanding tracheal stent so that it might be made available for clinical use. Using direct laryngoscopy, we placed polyurethane-coated, nitinol stents into the middle third of the trachea in 25 New Zealand rabbits. After a mean observation period of 26 days, we evaluated stent migration, degree of expansion, attachment, adherence, formation of granulation tissue, presence of inflammatory infiltrate, parietal involvement, and epithelial lining. The results showed complete radial expansion, little adherence to the tracheal mucosa, and low tissue attachment, as well as high rates of granuloma formation and stent migration. This new model proved to be biocompatible and showed a behavior similar to that of other stents on the market.

  13. [Treatment of a postoperative rectal stenosis with a self-expanding biodegradable polydioxanone stent].

    Science.gov (United States)

    Dederichs, F; Knüdeler, S; Nolte, W; Iesalnieks, I

    2013-05-01

    Rectal stricture is a serious although infrequent complication of transanal endoscopic microsurgery (TEM). In some cases, these strictures may be refractory to treatment by endoscopic balloon dilatation. Biodegradable stents might improve the outcome by providing an extended period of dilatation. Moreover, these stents can remain in place without the need to remove them. In the presented case, a biodegradable polidioxanone stent originally developed to treat benign oesophageal stenoses was used to treat a patient suffering from rectal stricture following a TEM. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Management of hilar bile duct carcinoma with high-dose radiotherapy and expandable metallic stent placement

    International Nuclear Information System (INIS)

    Saito, Hiroya; Takamura, Akio

    2000-01-01

    This article describes our experience with high-dose radiotherapy in combination with the placement of expandable metallic stents (EMS) in the management of hilar bile duct carcinoma. Between 1988 and 1999, 107 consecutive patients with hilar bile duct carcinoma were treated with EMS placement either alone or in combination with high-dose radiotherapy. External beam radiotherapy (EBRT) was indicated in 101 patients, and in 86 this was combined with intraluminal 192 Ir irradiation (ILRT, 59-98 Gy) EMS were placed after the completion of radiotherapy. The 1-, 2-, 3-, and 5-year actuarial survival rates for the radiotherapy group were 66.4%, 23.4%, 15.6%, 7.8%, respectively, and the 1- and 2-year actuarial survival rates for the nonradiotherapy group were 66.4% and 0%, respectively. The placement of EMS was useful for the early establishment of an internal bile passage in radically irradiated patients and the 1-, 2-, 3-, and 5-year actuarial patency rates for the radiotherapy group were 56.3%, 45.3%, 35.2%, and 23.4%, respectively, and the 1- and 2-year actuarial patency rates for the non radiotherapy group were 50.0% and 0% respectively. High-dose radiotherapy, consisting of ILRT and EBRT, appears to be feasible in the management of hilar bile duct carcinoma, and it offers a survival advantage for patients no suited for surgical resection. The placement of EMS assists the internal bile flow and lengthens survival after high-dose radiotherapy. (author)

  15. PulmoStent : In Vitro to In Vivo Evaluation of a Tissue Engineered Endobronchial Stent

    NARCIS (Netherlands)

    Thiebes, Anja Lena; Kelly, Nicola; Sweeney, Caoimhe A.; McGrath, Donnacha J.; Clauser, Johanna; Kurtenbach, Kathrin; Gesche, Valentine N.; Chen, Weiluan; Kok, Robbert Jan; Steinseifer, Ulrich; Bruzzi, Mark; O’Brien, Barry J.; McHugh, Peter E.; Jockenhoevel, Stefan; Cornelissen, Christian G.

    Currently, there is no optimal treatment available for end stage tumour patients with airway stenosis. The PulmoStent concept aims on overcoming current hurdles in airway stenting by combining a nitinol stent with a nutrient-permeable membrane, which prevents tumour ingrowth. Respiratory epithelial

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

    Science.gov (United States)

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

    2018-03-25

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

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

    Directory of Open Access Journals (Sweden)

    Yang Won Min

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

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

    Science.gov (United States)

    Di Mitri, R; Mocciaro, F

    2014-01-01

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

  19. Y-Shaped Bilateral Self-Expandable Metallic Stent Placement for Malignant Hilar Biliary Obstruction: Data from a Referral Center for Palliative Care

    Directory of Open Access Journals (Sweden)

    R. Di Mitri

    2014-01-01

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

  20. Treatment of Esophageal Variceal Hemorrhage with Self-Expanding Metal Stents as a Rescue Maneuver in a Swiss Multicentric Cohort

    Directory of Open Access Journals (Sweden)

    Fabienne C. Fierz

    2013-03-01

    Full Text Available Acute esophageal variceal bleeding in patients with portal hypertension remains a complication with a high mortality today. In cases refractory to standard therapy including endoscopic band ligation and pharmacological therapy, traditionally balloon tamponade has been used as salvage therapy. However, these techniques show several important limitations. Self-expanding metal stents (SEMS have been proposed as an alternative rescue treatment. The use of variceal stenting in 7 patients with a total of 9 bleeding episodes in three different Swiss hospitals is demonstrated. While immediate bleeding control is achieved in a high percentage of cases, the 5-day and 6-week mortality rate remain high. Mortality is strongly influenced by the severity of the underlying liver disease. Accordingly, our data represent a high-risk patient collective. Thanks to their safety and easy handling, SEMS are an interesting alternative to balloon tamponade as a bridging intervention to definitive therapy including the pre-hospital setting.

  1. Biliary self-expandable metallic stent using single balloon enteroscopy assisted ERCP: overcoming limitations of current accessories

    Directory of Open Access Journals (Sweden)

    Rolando Pinho

    2013-10-01

    Full Text Available Device assisted enteroscopy (DAE techniques have been recently developed for the diagnosis and treatment of small bowel diseases. These techniques can also be used to perform endoscopic retrograde cholangiopancreatography (ERCP in patients with surgically altered anatomies. The main difficulties with DAE-ERCP are related to type of surgery, to the different dimensions and lack of frontal view of the enteroscope and to the resulting limitations with the use of standard accessories, resulting in the need of dedicated accessory devices. Although most ERCP techniques have been successfully performed with DAE-ERCP, biliary self-expandable metallic stents (SEMS have not yet been used, as dedicated biliary SEMS for the enteroscope are lacking. The authors present a case report showing a new method to place standard biliary trough-the-scope SEMS with DAE-ERCP, using a different technique of stent deployment.

  2. An Efficient Finite Element Framework to Assess Flexibility Performances of SMA Self-Expandable Carotid Artery Stents

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    Mauro Ferraro

    2015-07-01

    Full Text Available Computer-based simulations are nowadays widely exploited for the prediction of the mechanical behavior of different biomedical devices. In this aspect, structural finite element analyses (FEA are currently the preferred computational tool to evaluate the stent response under bending. This work aims at developing a computational framework based on linear and higher order FEA to evaluate the flexibility of self-expandable carotid artery stents. In particular, numerical simulations involving large deformations and inelastic shape memory alloy constitutive modeling are performed, and the results suggest that the employment of higher order FEA allows accurately representing the computational domain and getting a better approximation of the solution with a widely-reduced number of degrees of freedom with respect to linear FEA. Moreover, when buckling phenomena occur, higher order FEA presents a superior capability of reproducing the nonlinear local effects related to buckling phenomena.

  3. Self-expandable metallic stent placement for patients with inoperable esophageal carcinoma. Investigation of the influence of prior radiotherapy and chemotherapy

    International Nuclear Information System (INIS)

    Ihara, Yuko; Murayama, Sadayuki; Toita, Takafumi; Utsunomiya, Takashi; Nagata, Osamu; Akamine, Tamaki; Ogawa, Kazuhiko; Adachi, Genki; Tanigawa, Noboru

    2006-01-01

    The aim of this study was to evaluate the efficacy and complications of self-expandable metallic stent placement for patients with inoperable esophageal carcinoma after radiotherapy and/or chemotherapy. We obtained data from 19 patients with advanced or recurrent esophageal carcinoma between 1996 and 2000. In all patients, a self-expandable metallic stent was placed under fluoroscopic guidance. Dysphagia before and after stent placement was graded. Complications after stent placement were also evaluated. Data were compared between patients with and without prior radiotherapy and/or chemotherapy. The procedure was technically successful in all but one patient. The dysphagia grade improved in all patients. No life-threatening complications occurred. The other major complications such as mediastinitis occurred in two patients, and pneumonia and funnel phenomenon occurred in one patient each. These patients had a history of radiotherapy and/or chemotherapy prior to stent placement. Eight of the twelve patients with prior radiotherapy and/or chemotherapy compared with one of seven patients without prior therapy had persistent chest pain, which was a statistically significant difference (P<0.05). Placement of self-expandable metallic stents was effective for patients with advanced or recurrent esophageal carcinoma. However, prior irradiation and/or chemotherapy increased the risk of persistent chest pain after stent placement. (author)

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

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    Martin Müller

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

  5. Utilização de endoprótese metálica no tratamento de estenose brônquica após transplante pulmonar Treatment of bronchial stenosis after lung transplantation using a self-expanding metal endobronchial stent

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    Marcos Naoyuki Samano

    2005-06-01

    Full Text Available As complicações decorrentes da anastomose brônquica nos transplantes pulmonares, embora tenham diminuído ao longo do tempo, ainda figuram como um dos principais fatores de morbi-mortalidade nesses pacientes. As formas de tratamento dessas complicações incluem dilatação por balão, fotocoagulação por laser, endopróteses de silicone e metálicas, e reoperação. Relata-se o caso de um paciente que apresentou estenose brônquica após transplante pulmonar unilateral esquerdo, cujo tratamento foi realizado com endoprótese metálica auto-expansível de nitinol (Ultraflex®. Embora seja um caso pioneiro no Brasil, a boa resposta clínica, concordante com os dados da literatura, sugere que esse tratamento seja uma boa alternativa nesses casos.Although the incidence of bronchial anastomosis as a complication of lung transplantation has decreased in recent years, it remains a significant cause of morbidity and mortality in these patients. Treatment options include balloon dilatation, laser photocoagulation, placement of a stent (silicone or metal, and performing a second operation. We report the case of a patient who presented bronchial stenosis after left lung transplantation and was treated with a self-expanding metal alloy (nitinol stent (Ultraflex®. Despite the fact that this was the first case of stenosis treated in this fashion in Brazil, the positive clinical response, in agreement with results reported in the literature, indicates that this treatment is a viable alternative in such cases.

  6. "Stent" auto-expansível nas dissecções da aorta tipo B Self-expanding stent in type B dissections of the aorta

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    Wagner Michael PEREIRA

    1999-07-01

    Full Text Available O tratamento clínico das dissecções agudas da aorta do tipo B tem mortalidade em torno de 25% menor que a mortalidade cirúrgica. O tratamento cirúrgico das dissecções crônicas também produz uma morbidade e mortalidade elevadas. A utilização de "stents"auto-expansíveis endovasculares pode ser uma nova alternativa no tratamento destas lesões. De abril a dezembro de 1998 foram implantados 15 "stents" endovasculares, 10 em dissecções agudas e 5 em crônicas. A idade dos pacientes variou entre 48 e 75 anos (média=60,53±9,73 anos com 66,6% do sexo masculino. Os pacientes foram submetidos à esternotomia mediana, circulação extracorpórea (CEC com hipotermia profunda (18° - 20°C, parada circulatória total (PCT e perfusão cerebral retrógrada (PCR. A aorta transversa foi incisada e implantado o "stent" na aorta descendente sob auxílio de aortoscopia. Foram analisados os tempos de CEC, pinçamento aórtico, PCT, PCR, reaquecimento, ventilação mecânica, internação, sangramento trans e pós-operatório, reposição sangüínea, gasometria, curva de eventos e sobrevida. A mortalidade hospitalar (30 dias foi de 6,6%; 2 pacientes foram reoperados com 3 e 6 meses após a operação com dissecção da aorta ascendente e aneurisma roto distal ao "stent". Quatorze vêm sendo acompanhados com 1 a 8m de evolução, sendo que 85,7% estão livres de eventos e curva de sobrevida de 93,1%(240 dias. Concluímos que o implante de "stent"intraluminais auto-expansíveis apresentou mortalidade menor na fase aguda da doença (6,6% comparada à nossa experiência anterior com o tratamento clínico (30%. Apesar da amostra ser pequena, o procedimento parece ser promissor e necessita mais acompanhamento.The clinical treatment of acute type B aortic dissection has a mortality of about 25%, therefore, less than surgical mortality. The surgical treatment of chronic dissections also produces a high morbidity and mortality. The use of self-expanding

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

    Science.gov (United States)

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

    2017-01-01

    Whether unilateral or bilateral drainage should be performed for malignant hilar biliary obstruction remains a matter of debate. Although a Y-stent with a central wide-open mesh facilitates bilateral stent placement, it has its own limitations. This study aims to evaluate the feasibility and efficacy of a newly designed Y-configured bilateral self-expanding metallic stent (SEMS) for the treatment of hilar biliary obstruction. In this retrospective study, 14 consecutive patients with unresectable malignant hilar biliary obstruction (Bismuth type II or higher), who underwent placement of a newly designed Y-configured bilateral SEMS for hilar biliary obstruction from April 2013 to March 2015, were included into this study. Data on technical success, clinical success, stent patency, complications and patient survival were collected. Technical and clinical success was 100 and 92.9 %, respectively. Mean serum bilirubin level was significantly decreased 1 month after stent placement (P hilar biliary obstruction using port docking deployment.

  8. Comparison on the Efficacy between Partially Covered Self-Expandable Metal Stent with Funnel-Shaped Enlarged Head versus Uncovered Self-Expandable Metal Stent for Palliation of Gastric Outlet Obstruction

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    Jung Wan Choe

    2018-01-01

    Full Text Available Background. Shape modification has been one of the methods adopted to improve stent patency but has not always translated into positive outcome. The aim of this study was to compare the efficacy of shape-modified partially covered self-expandable metal stent (SEMS that has enlarged head versus uncovered SEMS for palliation of gastric outlet obstruction (GOO. Methods. A total of 48 patients underwent insertion of either enlarged-head SEMS (n=24 or uncovered SEMS (uSEMS (n=24 for palliation of GOO from July 2009 to July 2016. Patients with inoperable or advanced malignancy were included. Technical feasibility and clinical outcomes were compared. Results. Technical success rate was 100% (24/24 and 95.8% (23/24 for enlarged-head SEMS group and uSEMS group, respectively. Clinical success rate was 87.5% (21/24 and 87.0% (20/23 for enlarged-head SEMS group and uSEMS group, respectively. The gastric outlet obstruction scoring system score significantly improved in both groups (p<0.001 for both. Mean survival was similar between the groups: enlarged-head SEMS group, 99.3 days (range, 19–358 days versus uSEMS group, 82.1 days (range, 11–231 days (p=0.418. The mean stent patency also showed no difference between the groups: enlarged-head SEMS group, 87.1 days (range, 8–358 days versus uSEMS group, 60.4 days (range, 2–231 days (p=0.204. With enlarged-head SEMS, distal migration did not occur, but proximal migration was observed in four cases. Conclusions. Distal migration was prevented by shaping the SEMS to have an enlarged head, but improvement in stent patency could not be observed.

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

    Science.gov (United States)

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

    2017-02-01

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

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

    Science.gov (United States)

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

    2018-01-01

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

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

    Science.gov (United States)

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

    1993-01-01

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

  12. Retrieval of a self-expanding metal stent after migration and incorporation in the omental bursa, using a gastroscopic-transgastric laparoscopic rendezvous technique.

    Science.gov (United States)

    Patrzyk, Maciej; Dierzek, Przemyslaw; Glitsch, Anne; Paul, Hartmut; Heidecke, Claus-Dieter

    2015-01-01

    Endoscopic drainage is a widely used treatment for pancreatic pseudocysts. Drainage-related complications may be related directly to the procedure or may occur later as stents migrate or erode into adjacent structures. Migration of a self-expanding metal stent into peritoneal cavity and incorporation in the omental bursa is rare. When endoscopic retrieval fails a combined laparoscopic-endoscopic (rendezvous technique) approach offers an alternative to open surgery. We report a case of successful gastroscopic-transgastric laparoscopic removal of a stent that was dislocated into the omental bursa after a ½ year observation period.

  13. Retrieval of a self-expanding metal stent after migration and incorporation in the omental bursa, using a gastroscopic-transgastric laparoscopic rendezvous technique

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    Maciej Patrzyk

    2015-01-01

    Full Text Available Endoscopic drainage is a widely used treatment for pancreatic pseudocysts. Drainage-related complications may be related directly to the procedure or may occur later as stents migrate or erode into adjacent structures. Migration of a self-expanding metal stent into peritoneal cavity and incorporation in the omental bursa is rare. When endoscopic retrieval fails a combined laparoscopic-endoscopic (rendezvous technique approach offers an alternative to open surgery. We report a case of successful gastroscopic-transgastric laparoscopic removal of a stent that was dislocated into the omental bursa after a ΍ year observation period.

  14. A Multicenter, Prospective Study of a New Fully Covered Expandable Metal Biliary Stent for the Palliative Treatment of Malignant Bile Duct Obstruction

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    Bret T. Petersen

    2013-01-01

    Full Text Available Background and Study Aims. Endoscopic placement of self-expanding metal stents (SEMSs is indicated for palliation of inoperable malignant biliary obstruction. A fully covered biliary SEMS (WallFlex Biliary RX Boston Scientific, Natick, USA was assessed for palliation of extrahepatic malignant biliary obstruction. Patients and Methods. 58 patients were included in this prospective, multicenter series conducted under an FDA-approved IDE. Main outcome measurements included (1 absence of stent occlusion within six months or until death, whichever occurred first and (2 technical success, need for reintervention, bilirubin levels, stent patency, time to stent occlusion, and adverse events. Results. Technical success was achieved in 98% (57/58, with demonstrated acute removability in two patients. Adequate clinical palliation until completion of followup was achievedin 98% (54/55 of evaluable patients, with 1 reintervention due to stent obstruction after 142 days. Mean total bilirubin decreased from 8.9 mg/dL to 1.2 mg/dL at 1 month. Device-related adverse events were limited and included 2 cases of cholecystitis. One stent migrated following radiation therapy. Conclusions. The WallFlex Biliary fully covered stent yielded technically successful placement with uncomplicated acute removal where required, appropriate reduction in bilirubin levels, and low rates of stent migration and occlusion. This SEMS allows successful palliation of malignant extrahepatic biliary obstruction.

  15. Self-Expandable Metal Stents for Colorectal Cancer: From Guidelines to Clinical Practice

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    Maria Pia Costa Santos

    2016-11-01

    Conclusions: In this study, stent placement was an effective procedure in obstructive colorectal cancer. It was mainly used as a bridge to elective surgery. However, a significant rate of silent perforation was observed, which may compromise the oncological outcome of these potentially curable patients. Prospective real life studies are warranted for a better definition of actual recommendations.

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

    Science.gov (United States)

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

    2017-07-01

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

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

    Science.gov (United States)

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

    2017-02-01

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

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

    Science.gov (United States)

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

    2015-11-01

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

  19. Outcomes of the Use of Fully Covered Esophageal Self-Expandable Stent in the Management of Colorectal Anastomotic Strictures and Leaks

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    Chad J. Cooper

    2014-01-01

    Full Text Available Introduction. Colorectal anastomotic leak or stricture is a dreaded complication leading to significant morbidity and mortality. The novel use of self-expandable metal stents (SEMS in the management of postoperative colorectal anastomotic leaks or strictures can avoid surgical reintervention. Methods. Retrospective study with particular attention to the indications, operative or postoperative complications, and clinical outcomes of SEMS placement for patients with either a colorectal anastomotic stricture or leak. Results. Eight patients had SEMS (WallFlex stent for the management of postoperative colorectal anastomotic leak or stricture. Five had a colorectal anastomotic stricture and 3 had a colorectal anastomotic leak. Complete resolution of the anastomotic stricture or leak was achieved in all patients. Three had recurrence of the anastomotic stricture on 3-month flexible sigmoidoscopy follow-up after the initial stent was removed. Two of these patients had a stricture that was technically too difficult to place another stent. Stent migration was noted in 2 patients, one at day 3 and the other at day 14 after stent placement that required a larger 23 mm stent to be placed. Conclusions. The use of SEMS in the management of colorectal anastomotic leaks or strictures is feasible and is associated with high technical and clinical success rate.

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

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    Canena Jorge Manuel

    2012-06-01

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