Prospective evaluation of a new self-expanding plastic stent for inoperable esophageal strictures

BACKGROUND: High stent cost is considered the major drawback of self-expanding metal stents for dysphagia palliation in patients with inoperable esophageal strictures. We report our experience with a self-expanding plastic (Polyflex) stent, the cost of which is half that of the metal stents. METHODS: Between September 1999 and April 2001, 16 dysphagic patients (15 men; mean age, 69.4 +/- 14.5 years; range, 49-100 years; mean dysphagia score, 3.31 +/- 0.6) with esophageal strictures who underwent Polyflex stent placement (insertion device diameter, 12-14 mm; postexpansion inner stent diameter, 16-21 mm; stent length, 9, 12, and 15 cm) were studied prospectively. The strictures were caused by postsurgical recurrence of gastric/esophageal cancer at the anastomotic site in five patients, primary esophageal cancer in four patients, esophagocardia junction cancer in four patients, metastatic mediastinal lymph nodes from a primary lung cancer invading the esophagus in 1 patient, and benign peptic stricture in two elderly patients. All the patients were prospectively followed until death. RESULTS: Stent insertion was technically successful in 12 patients (75%). Stent placement failed in four patients (25%) because of failure to pass the delivery catheter across the stricture in three patients and failure of the stent to open in one patient. Early and late stent migration occurred in two patients and 1 patient, respectively. Tumor overgrowth occurred in 1 patient. The mean dysphagia score 7 days after stent placement was 1.1 +/- 0.9. Mean survival was 100.6 +/- 71.2 days (range, 8-225 days). CONCLUSION: Self-expanding Polyflex stents are safe and effective for inoperable esophageal strictures and have an acceptable technical success rate. Further experience, better selection criteria, and design improvements should improve results.     

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

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

Expandable metal stent placement for benign colorectal obstruction: outcomes for 23 cases

Background Self-expanding metal stents (SEMS) are an established treatment for palliation of malignant colorectal strictures and as a bridge to surgery for acute malignant colonic obstruction. Patients with benign colonic strictures may benefit from stent placement, but little data exist for this indication. Methods All cases of colonic stent placement identified from a prospectively collected gastrointestinal database from April 1999 to August 2006 were reviewed. During the study period, 23 patients with benign obstructive disease underwent endoscopic SEMS placement. The etiologies of the stricture were diverticular/inflammatory (n = 16), postsurgical anastomotic (n = 3), radiation-induced (n = 3), and Crohn’s (n = 1) disease. All strictures were located in the left colon. Five patients had an associated colonic fistula. Uncovered Enteral Wallstents or Ultraflex Precision Colonic stents (Boston Scientific) were endoscopically placed in all but one patient. Results Stent placement was technically successful for all 23 patients, and obstruction was relieved for 22 patients (95%). Major complications occurred in 38% of the patients including migration (n = 2), reobstruction (n = 4), and perforation (n = 2). Of these major complications, 87% occurred after 7 days. Four patients did not undergo an operation. Of the 19 patients who underwent planned surgical resection, 16 were successfully decompressed and converted from an emergent operation to an elective one with a median time to surgical resection of 12 days (range, 2 days to 18 months). Surgery was delayed more than 30 days after stent placement for six of these patients. Of the 19 patients who underwent a colectomy, 8 (42%) did not need a stoma after stent insertion. Conclusions SEMS can effectively decompress high-grade, benign colonic obstruction, thereby allowing elective surgery. The use of SEMS can offer medium-term symptom relief for benign colorectal strictures, but this approach is associated with a high rate of delayed complications. Thus, if elective surgery is planned, data from this small study suggest that it should be performed within 7 days of stent placement. Podium presentation at the annual meeting of the Society of American Gastrointestinal and Esophageal Surgeons (SAGES), 18–22 April 2007 at Las Vegas, NV, USA     

Self-expanding metal stent for tracheobronchial strictures.

To determine the role of expandable metal stent (Wallstent) in treating tracheobronchial strictures, 12 patients with recurrent symptoms of airway obstruction due to either benign or malignant strictures were studied. The seven benign strictures were anastomotic stricture following sleeve resection (2) and single lung transplant (1), tracheal amyloidosis (1), idiopathic chondritis (2), and post-tracheostomy stricture (1). The five malignant strictures were due to recurrent adenoid cystic carcinoma of trachea (1), large-cell carcinoma of lung (1), recurrent laryngeal squamous carcinoma (1), squamous carcinoma of the trachea (1), and malignant melanoma (1). The placement of stents was performed under rigid bronchoscopic guidance with no complications. All patients with benign strictures derived subjective and functional improvement with stenting. No evidence of restenosis within the stented segment in six of the seven benign strictures was found within up to 24 months. Repeated diathermy resection was required in the patient with recurrent amyloidosis through the distal end of the stent. Among the malignant strictures, symptomatic relief was achieved in four of the five patients. One metal stent migrated proximally and was replaced by a Montgomery T tube. One patient with relief of stridor died at 4 months due to carcinomatosis. Tumour ingrowth through the metal stent remains problematic in two patients. However, the incidence of palliative interventions required has markedly reduced after stenting.     

Late complication after colon self-expandable metal stent placement: a case report

Treatment of acute colorectal malignant obstruction, by using self-expandable metallic stents is useful for both palliative and decompressive therapy before the final surgical treatment. In this case, the patient may be benefit from a period of medical optimization prior to undergoing planned surgical resection by a colorectal surgeon. This is a minimally invasive procedure, relatively safe, which obviates the need for colostomy for evacuation relieving physical and psychological burden and contributing the improvement of quality of life. Furthermore, this method also has the advantage of being cost-effective. The previous experience in the benign biliary stenosis allowed the extension of using the metallic stents also for the treatment of benign colorectal diseases (diverticular occlusion, anastomotic strictures, colonic endometriosis). Complications of colon self-expandable metallic stents placement may occur during the procedure and soon after placement (early complications) or, rarely, late after insertion (late complications). These include bleeding, re-obstruction, pain, tenesmus, stent migration, and perforation. The authors report a case of an 81 year-old woman with inoperable rectal carcinoma with liver metastasis who underwent palliative treatment of self-expanding metallic stent endoscopic placement. One month later, the patient presented with acute abdomen at Accidents and Emergencies Department. The diagnosis was a late rectosigmoid junction perforation by stent placement.     

Sequential silastic and expandable metal stenting for tracheobronchial strictures.

The risks and limitations of surgical resection and reconstruction for tracheobronchial strictures demand consideration of other therapeutic options that can alleviate the distressing symptoms of tracheobronchial obstruction. One alternative is to stent the obstructive lesion until surgical advances allow primary reconstruction or replacement of the critically diseased airway or until an ideal endoprosthesis is found. The latter requires uniformity in the distribution of expansile force, conformability and stability within the tracheobronchial tree, and ease of placement. Here we report our experience with the placement of expandable metal stents (Wall-stent) used in conjunction with our Silastic (Dow Corning) endobronchial stents in 5 patients with recurrent tracheal or bronchial strictures. The major site of obstruction was the trachea in 1 patient and a main bronchus or both bronchi in 4 patients. Three patients had a benign bronchial stricture (anastomotic stricture in 2, idiopathic polychondritis in 1), and 2 patients had an obstructive airway neoplasm. Placement of the stents was performed under rigid bronchoscopic guidance. We had no complications from our technique of stenting. There has been no evidence of restenosis or occlusion within the stented segment of airway. The complementary use of expandable metal and Silastic endobronchial stents provided symptomatic and functional improvement in our patients during follow-up ranging from 5 to 24 months.     

The role of endoscopic stents in the management of chronic anastomotic and staple line leaks and chronic strictures after bariatric surgery

BackgroundThe use of endoluminal stents has been proposed for the management of fistulas and anastomotic strictures after bariatric surgery. The objective of our study was to determine the success of endoscopically placed, self-expandable metal stents (SEMS) in bariatric patients specifically with either chronic persistent anastomotic or staple line leaks/fistulas or chronic, persistent anastomotic strictures.MethodsWe treated 21 patients including 5 with chronic staple line leaks/fistulas (4 from the gastric sleeve after biliopancreatic diversion with duodenal switch [BPD/DS] and 1 after removal of an eroding laparoscopic adjustable gastric band) and 16 with chronic anastomotic strictures (15 at the gastrojejunostomy after Roux-en-Y gastric bypass and 1 at the duodenoileal anastomosis after BPD/DS). Patients with early leaks or anastomotic strictures were excluded.ResultsAll but one of these patients had been referred to our institution after chronic treatment elsewhere was unsuccessful with prior stent placement for fistulas or multiple endoscopic dilations for strictures. Their bariatric operations had been performed a mean of 386 days beforehand. Stent placement was performed successfully in all patients without complications but was successful in only 4 of 21 patients (19%)—2 with chronic fistulas and 2 with chronic anastomotic strictures. Stent migration occurred in 10 patients (47%); the migrated stents were removed/replaced endoscopically in 7 patients but required elective operative removal in 3 with concomitant correction of the leak, fistula, or anastomotic stricture; none were operated emergently.ConclusionOnly 4 of 21 patients with a chronic persistent leak or anastomotic stricture were treated definitively using a SEMS. Although endoluminal stents may not lead to resolution of a chronic leak or stricture, SEMS may suppress ongoing sepsis and allow patients to undergo nutritional resuscitation orally before operative correction.     

A retrospective analysis of early and late outcome of biodegradable stent placement in the management of refractory anastomotic colorectal strictures

Background

Benign colorectal strictures are treated conventionally by endoscopic dilation. Experience using SEMS for benign colonic strictures is limited, and outcomes to date have been disappointing. Refractory colorectal strictures remain challenging to be treated with surgery. Polydioxanone-based stent are biodegradable (BD) stent CE approved for esophageal strictures. This study was designed to investigate retrospectively the safety and the efficacy of these stents for the management of strictures refractory to multiple sessions of dilation.

Methods

Patients with postsurgical benign strictures located within 20 cm from anal verge, refractory to mechanical or pneumatic dilation (at least 3 sessions) were included in this analysis. Clinical success was defined as the absence of occlusive symptoms and the ability to pass through the stricture with a regular size colonoscope. All patients were predilated before stent placement. Stents were released under fluoroscopic control. All patients were under stool softeners for 3 months. Follow-up was scheduled with endoscopic and fluoroscopic controls within 90 days from stent deployment and afterwards by telephone interview and/or ambulatory consultation.

Results

Eleven patients (7 males, mean age 62.3 ± 8.5 years) were included. Technical success was achieved in all the patients. Stent migration was observed in four patients within the first 2 weeks after stent placement. Stent migration was followed by recurrence of stricture and obstructive symptoms in all the cases. Among the seven patients who completed the process of stent biodegradation, five of them had complete resolution of the stricture and relief of symptoms. Two of 11 patients required surgical treatment during the follow-up period (mean 19.8 (range 42–15) months). The overall success rate of the BD stent was 45 %.

Conclusions

This retrospective analysis of a limited number of patients demonstrated that nondedicated esophageal BD stents are associated with high risk of migration and clinical success in less than 50 % of patients. Dedicated stents with large diameter and antimigration findings could potentially improve the outcome of patients with refractory benign colorectal strictures.     

Treatment of benign ureterointestinal anastomotic strictures with permanent ureteral Wallstent after Camey and Wallace urinary diversion: long-term follow-up

BACKGROUND AND PURPOSE: Ureterointestinal anastomotic stricture follows urinary diversion in 4% to 8% of patients and may lead to a progressive deterioration of renal function. There are problems with all current management techniques: surgical revision, endourologic incision, nephrostomy drainage, external ureteral stents, and dilation with a high-pressure angioplasty balloon. The authors present their long-term results with permanent ureteral Wallstents for the treatment of benign ureterointestinal stricture. PATIENTS AND METHODS: Eight patients with 10 strictures were treated by placement of self-expanding permanent indwelling stents via percutaneous nephrostomy between September 1993 and January 1998. The mean age of the group was 59.2 years. Development of strictures occurred a mean of 20.9 months after urinary diversion. There were seven complete and three partial strictures. Of 49 patients treated by the Camey procedure, 7 patients (14%) developed 9 (18%) strictures. Of 28 patients having the Wallace procedure, 1 patient (3.5%) developed one stricture. After recanalization of the distal ureter by a Terumo guidewire and dilation with a high-pressure angioplasty balloon, a Wallstent was placed across the stricture via a percutaneous approach. RESULTS: The endourologic placement of the Wallstent was well tolerated by all patients. The hospital stay averaged 2 days. Seven patients with nine strictures after the Camey procedure are doing well with a follow-up of 7 to 68 months (mean 22.4 months). One major complication was observed in one patient necessitating an additional procedure (lithotripsy) because of stone formation at the lower part of the stent extending into the neobladder in order to maintain patency after 68 months. The other patient, who had a Wallace procedure, is doing well 1 year 8 months afterward. CONCLUSION: An endourologic ureteral Wallstent approach to ureterointestinal stricture is a successful alternative, providing satisfactory management of the problem in most patients. No complication such as stent migration, hematuria, pain, or recurrent stricture was observed.     

URETEROILEAL ANASTOMOTIC STRICTURES: AN INNOVATIVE APPROACH WITH METALLIC STENTS

Purpose

We report our experience with the use of self-expandable metallic stents to bypass anastomotic strictures after ureteroileal urinary diversion.

Materials and Methods

We evaluated 3 men and 1 woman with invasive bladder carcinoma who underwent radical cystectomy and ileal conduit urinary diversion. Ureteroenteric anastomotic strictures developed after a mean of 16 months. Self-expandable metallic stents were successfully placed (bilaterally in 2) comprising 6 stented ureters that bypassed strictures. Mean patient age was 64 years and mean followup was 12 months.

Results

No restenosis was observed in 3 patients during followup. The stricture recurred 1 month after stent placement in the remaining patient and additional intervention was necessary, consisting of placement of a totally coaxial overlapping metal stent. No sepsis or other complication was observed. One patient died of metastatic disease 12 months after stent placement.

Conclusions

We propose the use of metal stents as an adequate, safe and effective alternative treatment for anastomotic strictures after ureteroileal diversion.     

Treatment of anastomotic stenosis and leakage after colorectal resection for cancer with self-expandable metal stents

Background

Self-expandable metallic stents can be used to treat patients with symptomatic anastomotic complications after colorectal resection.

Methods

Twenty patients with symptomatic anastomotic stricture after colorectal resection were treated with endoscopic placement of a self-expandable metal stent. Ten patients had “simple” anastomotic stricture. In the remaining 10 patients, a leak was associated with the stricture.

Results

The anastomotic leakage healed without evidence of residual stricture or major fecal incontinence in 8 of 10 patients. Overall, the anastomotic stricture was resolved in 14 of the 20 patients.

Conclusions

Self-expandable metal stents represent a valid adjunctive to treat patients with symptomatic anastomotic complications after colorectal resection for cancer. They have a complementary role to balloon dilatation in case of simple anastomotic stricture, and they improve the rate of healing when the stricture is associated with a leak.     

Endoscopic stenting for benign upper gastrointestinal strictures and leaks

Background

Self-expandable metal stents (SEMS) and self-expandable plastic stents (SEPS) maybe used for the treatment of benign upper gastrointestinal (GI) leaks and strictures. This study reviewed our experience with stent insertions in patients with benign upper GI conditions.

Methods

Patients who underwent stent placement for benign upper GI strictures and leaks between March 2007 and April 2011 at a tertiary referral academic center were studied using an endoscopic database and electronic patient records. The technical success, complications, and clinical improvement after stent removal were compared according to type of stent. The outcomes measured were clinical response, adverse events, and predictors of stent migration.

Results

Thirty-eight patients (50 % male, mean age = 54 years, range = 12–82) underwent 121 endoscopic procedures. Twenty patients had stents placed for strictures, and 18 had stents placed for leaks. Stent placement was technically successful in all patients. The average duration of stent placement was 54 days (range = 18–118). Clinical improvement immediately after stent placement was seen in 29 of the 38 patients (76.3 %). Immediate post-procedure adverse events occurred in 8 patients. Late adverse events were seen in 18 patients. Evidence of stent migration occurred in 16 patients and was seen in 42 of the 118 successfully placed stents (35.5 %). Migration was more frequent with fully covered SEMS (p = 0.002). After stent removal, 27 patients were evaluable for long-term success (median follow-up time of 283 days, IQR 38–762). Resolution of strictures or leaks was seen in 11 patients (40.7 %). Predictors for long-term success included increasing age and if the stent did not cross the GE junction.

Conclusions

Placement of SEPS and SEMS for benign refractory strictures and fistulas has modest long-term clinical efficacy and is limited by a significant migration rate. Stent migration is common and frequent with fully covered SEMS compared to other types of stents, regardless of indication or location.     

Use of endoscopic stents to treat anastomotic complications after bariatric surgery

BACKGROUND: Complications after bariatric surgery often require longterm parenteral nutrition to achieve healing. Recently, endoscopic treatments have become available that provide healing while allowing for oral nutrition. The purpose of this study was to present outcomes of the largest series to date treating staple line complications after bariatric surgery with endoscopic covered stents. STUDY DESIGN: A retrospective evaluation was performed of all patients treated for staple line complications after bariatric surgery at a single tertiary care bariatric center. Acute postoperative leaks, chronic gastrocutaneous fistulas, and anastomotic strictures refractory to endoscopic dilation after both gastric bypass and sleeve gastrectomy were included. RESULTS: From January 2006 to June 2007, 19 patients (11 with acute leaks, 2 with chronic fistulas, and 6 with strictures) were treated with a total of 34 endoscopic silicone covered stents (23 polyester, 11 metal). Mean followup was 3.6 months. Immediate symptomatic improvement occurred in 90% (91% of acute leaks, 100% of fistulas, and 84% of strictures). Oral feeding was started in 79% of patients immediately after stenting. Resolution of leak or stricture after stent treatment occurred in 16 of 19 patients (84%). Healing of leak, fistula, and stricture occurred at means of 33 days, 46 days, and 7 days, respectively. Three patients (1 with leak, 1 with fistula, and 1 with stricture) had unsuccessful stent treatment. Migration of the stent occurred in 58% of 34 stents placed. Most migration was minimal, but three stents were removed surgically after distal small bowel migration. There was no mortality. CONCLUSIONS: Treatment of anastomotic complications after bariatric surgery with endoscopic covered stents allows rapid healing while simultaneously allowing for oral nutrition. The primary morbidity is stent migration.     

经皮经肝胆道支架术在肝移植术后胆管狭窄中的应用

目的 评价经皮经肝胆道支架术治疗肝移植术后胆管狭窄的疗效.方法 肝移植术后胆管狭窄患者23例,其中吻合口狭窄7例,肝门区狭窄6例,多发性狭窄10例.确诊后均行经皮经肝胆道支架术.术前均给予经皮经肝胆管引流术(percutaneous transhepatic biliary drainage,PTBD),同时对狭窄部位...     

Percutaneous placement of permanent metal stents for treatment of ureteroenteric anastomotic strictures

PURPOSE: To evaluate the efficacy of permanent metal stent placement in the treatment of ureteroenteric anastomotic strictures following failed balloon dilation or laser endoureterotomy. PATIENTS AND METHODS: Metal stents were placed in six ureteroenteric anastomotic strictures in four patients presenting with recurrent obstruction after balloon dilation or laser endoureteromy. Patients were evaluated at 1 week postoperatively with antegrade ureterography and at 3 to 6 months with renal ultrasound or CT scans. Serum creatinine assays and physical examination were performed at serial postoperative clinic visits. RESULTS: At 1-week follow-up, antegrade studies demonstrated a patent anastomosis in all six strictures. With a mean follow-up of 10 months (range 7-12 months), no stricture recurrence has been seen. All patients have been clinically stable, without episodes of pyelonephritis, flank pain, or need for indwelling stents or nephrostomy tube placement. Serum creatinine concentrations have been stable in all patients. CONCLUSIONS: Metal stents offer a useful treatment option in patients who develop ureteroenteric anastomotic strictures after urinary diversion. Further, such stents may be used in patients failing balloon dilation or laser endoureterotomy. Further study to assess the long-term durability of metal stent placement is needed.     

Management of acute malignant large-bowel obstruction with self-expanding metal stent

Background Colorectal stents are being used for palliation and as a “bridge to surgery” in obstructing colorectal carcinoma. The purpose of this study was to review our experience with self-expanding metal stents (SEMS) as the initial interventional approach in the management of acute malignant large bowel obstruction. Methods Between February 2002 and May 2006, 67 patients underwent the insertion of a SEMS for an obstructing malignant lesion of the left-sided colon or rectum. Results In 55 patients, the stents were placed for palliation, whereas in 12 they were placed as a bridge to surgery. Stent placement was technically successful in 92.5% (n = 62), with a clinical success rate of 88% (n = 59). Two perforations that occurred during stent placement we retreated by an emergency Hartmann operation. In intention-to-treat by stent, the peri-interventional mortality was 6% (4/67). Stent migration was reported in 3 cases (5%), and stent obstruction occurred in 8 cases (13.5%). Of the nine patients with stents successfully placed as a bridge to surgery, all underwent elective single-stage operations with no death or anastomotic complication. Conclusions Stent insertion provided an effective outcome in patients with malignant colonic obstruction as a palliative and preoperative therapy.     

Systematic appraisal of the role of metallic endobiliary stents in the treatment of benign bile duct stricture

OBJECTIVE: To carry out a systematic appraisal of the current status of the use of metallic endobiliary stents in the treatment of benign biliary strictures. METHODS: A computerized search of the MEDLINE and EMBASE databases identified 37 studies providing detailed clinical course data on outcome of metallic endobiliary stent placement in 400 patients. Pooled data were examined for etiology of stricture, indications for stent placement, procedure-related complications, and outcome with reference to stent patency. RESULTS: The median (range) number of patients per report was 8 (2-54) with a median recruitment period of 44 (9-126) months. The most frequent indications were postoperative biliary strictures in 123 (31%), stenosed biliary-enteric anastomoses in 79 (20%), and biliary strictures following liver transplantation in 88 (22%). During a median follow up of 31 (1-111) months, 139 (35%) stents occluded, and there are little patency data beyond 2 years after deployment, with 99 (25%) known to be patent at 3 years from stent placement. CONCLUSIONS: These pooled data on 400 patients constitute the largest collective report to date on the use of metallic endobiliary stents for benign biliary strictures. The results show a critical lack of data on long-term patency such that at the present time, metallic endobiliary stents should not be used for benign stricture in those patients with a predicted life expectancy greater than 2 years.     

Migration of biliary plastic stents: experience of a tertiary center

Background and study aims  Stent migration occurs in about 5–10% of patients undergoing biliary stenting. The aim of this study was to analyze the risk factors for stent migration in patients with benign and malignant strictures. Patients and methods  We retrospectively analyzed records of 524 biliary plastic stent placement procedures. Details noted included the cause and localization of stricture, characteristics and number of stents, direction of stent migration, presentation of patient with migrated stent, and the methods used for retrieval of migrated stents. Results  Two hundred and four (38.9%) of the procedures were performed for benign biliary strictures (BBS) and 320 (61.1%) for malignant biliary strictures (MBS). Thirty-four patients had 45 migrated biliary stents. The rate of migration was 8.58% (proximal 4.58% and distal 4.00%). Migration frequency was higher in BBS compared with MBS (13.7% versus 5.3%, p = 0.001). In BBS, the rate of stent migration was higher in cases with one (19.3%) and two stents (20.9%) when compared with cases with multiple stents (2.7%) (p = 0.001; p = 0.001, respectively). Migration occurred more frequently (10.9%) in cases with two stents when compared both to cases with one stent (3.0%) and those with multiple stents (0%) in MBS (p = 0.008; p = 0.020, respectively). In BBS, short stents migrated more frequently proximally (77%) and long stents more frequently distally (73%) (p = 0.008). In BBS, migration in cases with proximal stricture occurred more frequently distally (76.9%), while in those with distal stricture, migration was more frequently proximal (73.3%) (p = 0.008). All of the proximally migrated stents could be successfully retrieved endoscopically. Conclusions  The risk of stent migration is higher in BBS compared with in MBS. The cases with multiple stents had significantly lower stent migration. In BBS, long stent, proximal and postcholecystectomy strictures were associated with distal migration, while short stent, distal and non-postcholecystectomy strictures were associated with proximal migration.     

Experience with urethral stent explantation

PURPOSE: We examined the timing, causes and results of the explantation of UroLume (American Medical Systems, Minnetonka, Minnesota) urethral stents. MATERIALS AND METHODS: The North American Study Group enrolled 465 patients in a trial of UroLume stent placement, including 69 (14.8% of the series) who required removal of a total of 73 stents (15.6% of stents) in 7 years. The time of explantation, reason for stent removal and local histological findings were determined from patient charts and reviewed in relation to the indication for stent placement. RESULTS: In patients treated for bladder outlet obstruction secondary to benign prostatic hyperplasia 23% of the stents were removed, as were 5% of those implanted in patients with bulbar urethral stricture and 22% of those in patients with detrusor-sphincter dyssynergia (see figure). Of the explantations 43.8% were done during year 1. Migration and/or inappropriate placement was the cause in 38.4% of cases. The most common stent site tissue finding was focal inflammation with a hyperplastic tissue response. Stent specific malignant changes were not observed. Stent removal was feasible with no sequelae. CONCLUSIONS When used appropriately, the UroLume endoprosthesis has a low incidence of failure. Stent removal is technically feasible and options are available for subsequent therapy. Local tissue reaction is minimal.     

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

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