Use of metallic stents and balloons in the esophagus and gastrointestinal tract

CIRSE Standards of Practice on Placement of Upper Gastrointestinal Stents

BACKGROUND

Image-guided insertion of stents in the upper gastrointestinal trunk is an effective, minimally invasive treatment option to provide immediate relief of symptoms caused by upper gastrointestinal tract obstruction related to advanced-stage malignant causes or benign causes that lead to lumen narrowing.

PURPOSE

This document, as with all CIRSE Standards of Practice documents, is not intended to impose a standard of clinical patient care but will recommend a reasonable approach to best practices for performing stenting of the upper gastrointestinal tract, namely the oesophageal and gastroduodenal segments. Our purpose is to provide up-to-date recommendations for placement of upper gastrointestinal tract stents based on the previously published guidelines on this topic in 2005 and 2007.

METHODS

The writing group was established by the CIRSE Standards of Practice Committee and consisted of a group of internationally recognised experts in performing upper gastrointestinal stenting. The writing group reviewed the existing literature using PubMed to search for relevant publications in the English language up to September 2021. The final recommendations were formulated through consensus.

CONCLUSION

Insertion of stents in the oesophageal and gastroduodenal tracts has an established role in the successful management of malignant or benign obstructions. This Standards of Practice document provides up-to-date recommendations for the safe performance of upper gastrointestinal stent placement.

Fluoroscopic-guided insertion of self-expanding metal stents for malignant gastroduodenal outlet obstruction: immediate results and clinical outcomes

BACKGROUND

Application of self-expanding metal stents (SEMS) to treat patients suffering from malignant gastroduodenal outlet obstruction (GDOO) is today considered a well-recognized palliative treatment. Use of SEMS has emerged as an attractive alternative to surgical treatment of such patients.

PURPOSE

To report the immediate and the mid-term clinical outcomes from a series of consecutive patients treated with exclusively fluoroscopic-guided insertion of SEMS.

MATERIAL AND METHODS

This was a retrospective study including patients suffering from GDOO that were either ineligible for or unwilling to undergo surgery. Patients with potentially curable disease, uncorrectable coagulopathy, gastrointestinal perforation, sepsis, presence of distal small bowel obstruction, and bowel ischemia were excluded. Technical success, clinical success, and major complications were calculated. In addition, stent migration, stent re-obstruction, restenosis, and overall re-interventions due to recurrent symptoms were considered. Kaplan-Meier survival analysis was used for patient survival estimation while both bivariable and multivariable analysis were performed to identify any independent predictors of outcomes.

RESULTS

Fifty-one patients, (mean age, 63.73 ± 15.62 years) met the study's criteria and were included in the final analysis. Technical and clinical success were 90.19% (n = 46/51) and 91.30% (n = 42/46), respectively. Major complications rate was 3.92%. Stent migration was noted in four cases. Restenosis and re-obstruction rates were 19.57% and 10.87%, respectively. No cases of peri-procedural mortality were noted, while Kaplan-Meier estimates for 1- and 2-year survival were 16.8% and 7.2%, respectively. Clinically successful cases and patients with primary GI tumor were related with more favorable survival compared to unsuccessful and patients suffering from GDOO due to extrinsic compression by neoplastic or lymph node disease.

CONCLUSION

Exclusively fluoroscopically inserted SEMS for GDOO is safe and highly effective method for palliative treatment.

Esophagojejunal anastomosis fistula, distal esophageal stenosis, and metalic stent migration after total gastrectomy

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

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

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

Palliation of esophageal cancer with a double-layered covered nitinol stent: long-term outcomes and predictors of stent migration and patient survival

PURPOSE

To evaluate the long-term clinical outcomes and the negative predictors after the deployment of double-layered stents in malignant esophageal strictures.

METHODS

This is a single-center study of patients who received a double-layered covered stent for the palliation of dysphagia due to malignant esophageal strictures in a 3-year period. 56 patients fulfilled the inclusion criteria. The study's primary end points were technical success, dysphagia improvement, stent migration, and complication rates; secondary end points were the stent's primary patency and overall survival. Cox regression analysis was used to adjust for confounding variables and to identify predictors of survival outcomes.

RESULTS

Technical success was 95%. Median dysphagia score improved significantly after stenting (p < 0.0001). Stent migration rate was 7.1% and occurred exclusively in the group of patients who received chemoradiotherapy (p < 0.01). The median stent patency was 87 days (range 5-444 days). Dysphagia reoccurred in 39.3% and was successfully managed with restenting in 98.2%. The median survival was 127 days (range 15-1480 days). Chemoradiotherapy and baseline histology did not influence survival outcomes. Survival was adversely affected by metastases (p = 0.005) and poor oral intake (p = 0.048). Patient survival was improved by repeat stenting in case of tissue overgrowth (p = 0.06).

CONCLUSION

The device is safe and effective for the treatment of patients with dysphagia due to esophageal cancer. Migration rate is zero for patients who do not receive chemoradiotherapy. Reintervention when required is a positive survival predictor.

Shaping tissue with shape memory materials

After being severely and quasi-plastically deformed, shape memory materials are able to return to their original shape at the presence of the right stimulus. After a brief presentation about the fundamentals, including various shape memory effects, working mechanisms, and typical shape memory materials for biomedical applications, we summarize some major applications in shaping tissue with shape memory materials. The focus is on some most recent development. Outlook is also discussed at the end of this paper.

Sutureless primary repair of colonic perforation with a degradable stent in a porcine model of fecal peritonitis

PURPOSE

Colonic perforation with fecal peritonitis is a life-threatening clinical condition. For these patients, a two-stage operation of fecal diversion and a postponed colostomy closure is generally recommended. Accordingly, a simple and feasible primary repair technique was explored.

METHODS

A sutureless banding method using a biodegradable stent and a porcine model of artificial colonic perforation were introduced. The colonic perforation model was created successfully with an open procedure in 34 pigs. The primary repair with a stent or the conventional hand-sewn control was performed 72 h later. Morbidity and mortality were recorded. Pigs in each group were also sacrificed to evaluate the healing on postoperative days (PODs) 3, 7, 14, and 90. The peripheral white blood cell counts, albumin, anastomotic bursting pressure, hydroxyproline contents, and histology data were evaluated.

RESULTS

There were 17 pigs in either group. Four pigs (23.5 %) of the control group died, but no mortality occurred in the stent group. There were no significant differences in white blood cell counts and albumin. Though anastomotic hydroxyproline contents between the two groups were comparable, the collagen per protein ratio on POD 14 in the stent group was higher, as well as the bursting pressure on PODs 3 and 7. Microscopically, the local inflammation of the cut edges in the control group was more severe, and the collagen synthesis started later.

CONCLUSIONS

A sutureless primary repair of a colonic perforation with a degradable stent is a feasible method in a porcine model of fecal peritonitis.

Precancerous lesions of gastric cancer: Research progress and preventive strategies

The development of precancerous lesions of gastric cancer is a critical stage of the evolution of gastric cancer. Early detection and intervention for these lesions are of considerable significance in reducing the morbidity of gastric cancer. The development of precancerous lesions of gastric cancer is controlled by multiple factors such as Helicobacter priori infection, DNA methylation, microsatellite instability, and p53 status. Because of high malignancy and unclear etiology of gastric cancer, there are certain difficulties in carrying out successful primary prevention. This review aims to review the recent advances in understanding the pathogenesis of and preventive strategies for gastric precancerous lesions.

An Auxetic structure configured as oesophageal stent with potential to be used for palliative treatment of oesophageal cancer; development and in vitro mechanical analysis

Oesophageal cancer is the ninth leading cause of malignant cancer death and its prognosis remains poor. Dysphagia which is an inability to swallow is a presenting symptom of oesophageal cancer and is indicative of incurability. The goal of this study was to design and manufacture an Auxetic structure film and to configure this film as an Auxetic stent for the palliative treatment of oesophageal cancer, and for the prevention of dysphagia. Polypropylene was used as a material for its flexibility and non-toxicity. The Auxetic (rotating-square geometry) structure was made by laser cutting the polypropylene film. This flat structure was welded together to form a tubular form (stent), by an adjustable temperature control soldering iron station: following this, an annealing process was also carried out to ease any material stresses. Poisson's ratio was estimated and elastic and plastic deformation of the Auxetic structure was evaluated. The elastic and plastic deformation behaviours of the Auxetic polypropylene film were evaluated by applying repetitive uniaxial tensile loads. Observation of the structure showed that it was initially elastically deformed, thereafter plastic deformation occurred. This research discusses a novel way of fabricating an Auxetic structure (rotating-squares connected together through hinges) on Polypropylene films, by estimating the Poisson's ratio and evaluating the plastic deformation relevant to the expansion behaviour of an Auxetic stent within the oesophageal lumen.

Malignant gastric outlet obstructions: treatment with self-expandable metallic stents

Unresectable malignant gastric outlet obstruction (GOO) severely affects the quality of life, with complications that include nausea, vomiting, aspiration, pain, and malnutrition. Although palliative surgical procedures have been traditionally performed, they are associated with high morbidity and mortality rates. Placing self-expandable metallic stents is associated with higher clinical success rates, lower morbidity, shorter time from the procedure to starting oral intake, lower incidence of delayed gastric emptying, and a shorter hospital stay than palliative surgery. Fluoroscopic or endoscopic placement of either bare or covered self-expandable metallic stents is a safe, nonsurgical, palliative treatment option for unresectable malignant GOOs, with a high clinical success rate and a low rate of serious complications. Stent obstruction and migration are the most common complications, but most can be managed by interventional treatments. Although there have been substantial developments in stent design over the past decade, large prospective, randomized studies are required to determine the ideal stent for malignant GOOs.

Stenting of the upper gastrointestinal tract: current status

Minimally invasive image-guided insertion of self-expanding metal stents in the upper gastrointestinal tract is the current treatment of choice for palliation of malignant esophageal or gastroduodenal outlet obstructions. A concise review is presented of contemporary stenting practice of the upper gastrointestinal tract, and the procedures in terms of appropriate patient evaluation, indications, and contraindications for treatment are analyzed, along with available stent designs, procedural steps, clinical outcomes, inadvertent complications, and future technology. Latest developments include biodegradable polymeric stents for benign disease and radioactive or drug-eluting stents for malignant obstructions.

Novel deployment of a covered duodenal stent in open surgery to facilitate closure of a malignant duodenal perforation

Background

Its a dilemma to attempt a palliative procedure to debulk the tumour and/or prevent future obstructive complications in a locally advanced intra abdominal malignancy.

Case presentation

A 38 year old Vietnamese man presented with a carcinoma of the colon which had invaded the gallbladder and duodenum with a sealed perforation of the second part of the duodenum. Following surgical exploration, it was evident that primary closure of the perforated duodenum was not possible due to the presence of unresectable residual tumour.

Conclusion

We describe a novel technique using a covered duodenal stent deployed at open surgery to aid closure of a malignant duodenal perforation.

Self expanding wall stents in malignant colorectal cancer: is complete obstruction a contraindication to stent placement?

OBJECTIVE

Technical failures have previously been associated with complete clinical obstruction and complete block to the retrograde flow of gastrograffin is considered by some to be a contraindication to the procedure. We report on the technical and clinical success rates of self-expanding metallic stents (SEMS) in both complete and incomplete obstruction in a prospective series of malignant colorectal obstructions.

METHOD

A prospective study of all patients undergoing attempted palliative and bridge to surgery SEMS placement for malignant colorectal obstruction over a 7-year period (April 1999-October 2006) was undertaken.

RESULTS

Seventy-two patients (49 males) with a mean age of 71 years (range 49-98) were included. Technical success was achieved in 27 of 32 patients (84%) with complete obstruction and 33 of 36 patients (92%) with incomplete obstruction, P < 0.46, Fishers exact test. Clinical success was achieved in 17 of 26 patients (65%) with complete obstruction and 24 of 33 patients (73%) with incomplete obstruction, P < 0.58, Fishers exact test. Although placed correctly in 89% cases, relief of symptoms occurred in only 71%, P = 0.002, matched pairs test. There were two colonic perforations in the series with one procedure related death.

CONCLUSION

Placement of SEMS for obstructing colorectal cancer is technically successful in a high proportion of cases. Complete radiological obstruction is not a contraindication to stent placement. The relief of obstructive symptoms following successful placement of a wall stent is less predictable.

Terminal Ileum Perforation as a Consequence of a Migrated and Fractured Oesophageal Stent

Covered self-expanding metallic stents are commonly employed to relieve malignant oesophageal obstruction. We report a case of a patient with oesophageal cancer treated by stent insertion and curative chemoradiotherapy with subsequent stent migration to the stomach. The stent fractured with the distal fragment migrating as far as the terminal ileum where it caused perforation of the bowel.

Covered expandable nitinol stents for malignant gastroduodenal obstructions

BACKGROUND AND AIM

The aim of the present study was to investigate the clinical effectiveness, safety, and outcome associated with the use of covered expandable Nitinol stents (Taewoong Medical, Seoul, Korea) for the treatment of malignant gastroduodenal obstructions.

METHODS

Between March 2001 and October 2004, covered expandable Nitinol stents were placed in 68 consecutive patients under endoscopic and fluoroscopic guidance for the following reasons: gastric carcinoma (n = 49), recurrent carcinoma after partial gastrectomy (n = 7), or another malignant neoplasm involving the duodenum (n = 12).

RESULTS

Technical success was achieved in 60 of the 68 patients (88.2%). After stent placement, mean dysphagia score improved from a mean of 3.5 to 1.2 (P < 0.001). The mean period of primary stent patency was 107.2 days. During follow up (mean 4.4 months; range, 1-15 months), major complications (migration [6], bleeding [3], perforation [1], ingrowth [1], overgrowth [7], fistula [1]) occurred in 19 patients (27.9%), and stent migration occurred in six (8.8%) (proximal migration into the stomach [n = 3], or distal migration [n = 3]). Recurrent dysphagia (mainly due to tumor ingrowth/overgrowth) occurred in eight patients (11.8%).

CONCLUSION

Covered expandable Nitinol stents appear to offer an effective and feasible palliative therapy in patients with a malignant gastroduodenal obstruction.

Randomised comparison of the FerX Ella antireflux stent and the ultraflex stent: proton pump inhibitor combination for prevention of post-stent reflux in patients with esophageal carcinoma involving the esophago-gastric junction

BACKGROUND AND AIM

Metal stents placed across the gastroesophageal junction in patients with malignant dysphagia frequently present with reflux symptoms. We compared an antireflux stent with a standard open stent used in combination with proton pump inhibitor medication.

METHODS

Forty-nine patients with dysphagia due to inoperable carcinoma in the lower third of the esophagus were randomly selected to receive either a antireflux valve stent (FerX-Ella) (n = 22) or a covered standard open stent (Ultraflex), which was combined with proton pump inhibitors such as omeprazole (n = 26). The technical success, the presence of reflux, and complications were recorded.

RESULTS

Reflux was seen in 3/22 patients (13.6%) in the FerX-Ella group and in 2/26 patients (7.7%) in the Ultraflex and proton pump inhibitor combination group (P-value not significant). In both groups, a significant improvement in the dysphagia score was seen and no statistically significant difference was detected between the two groups (P = 0.84). The FerX-Ella stents migrated more frequently (32%) than the Ultraflex stents (23%). This also necessitated surgical intervention more frequently in the FerX-Ella group (2/22, 9.1%) compared to the Ultraflex group (1/26, 3.8%).

CONCLUSION

The antireflux stent had no demonstrable advantages compared to the combination of standard open stent and proton pump inhibitor medication.

Palliative antecolic isoperistaltic gastrojejunostomy: a randomized controlled trial comparing open and laparoscopic approaches

Gastric outlet obstruction is a common, often preterminal, event for patients with inoperable neoplasms of the distal stomach, duodenum, and biliopancreatic area. It can be surgically managed by open or laparoscopic gastrojejunostomy. This study aimed to compare the results of open and laparoscopic palliative gastrojejunostomy for patients with gastric outlet obstruction resulting from inoperable neoplasms. A total of 24 patients were randomized prospectively to undergo laparoscopic (12 patients) or open (12 patients) palliative laterolateral antecolic isoperistaltic gastrojejunostomy. All the procedures were completed as planned. The mean duration of surgery was not significantly different between the two groups (p = 0.75). The mean intraoperative blood loss was significantly less after laparoscopic gastrojejunostomy (LGJ) (p = 0.0001). Time to oral solid food intake was longer after open gastrojejunostomy (OGJ) (p = 0.04). Two patients in the OGJ group experienced postoperative delayed gastric empting, whereas no patients in the LGJ group experienced such a complication (p = 0.04). The mean postoperative stay was shorter in the LGJ group, but the difference did not reach statistical significance (p = 0.65). No readmissions were registered after a minimum follow-up period of 2 months. The findings show that LGJ is a safe, feasible, and effective alternative to OGJ. However, because the current data involved only a small number of patients, large studies still are required for further evaluation of the this operation's effectiveness.

Treatment of gastric outlet and duodenal obstructions with uncovered expandable metal stents

AIM: To investigate and evaluate the technical feasibility and clinical effectiveness of fluoroscopically guided peroral uncovered expandable metal stent placement to treat gastric outlet and duodenal obstructions.

METHODS: Fifteen consecutive patients underwent peroral placement of Wallstent^TM Enteral Endoprosthesis to treat gastric outlet and duodenal obstructions (14 malignant, 1 benign). All procedures were completed under fluoroscopic guidance without endoscopic assistance. Follow-up was completed until the patients died or were lost, and the clinical outcomes were analyzed.

RESULTS: The technique success rate was 100%, and the oral intake was maintained in 12 of 14 patients varying from 7 d to 270 d. Two patients remained unable to resume oral intake, although their stents were proven to be patent with the barium study. One patient with acute necrotizing pancreatitis underwent enteral stenting to treat intestinal obstruction, and nausea and vomiting disappeared. Ten patients died during the follow-up period, and their mean oral intake time was 50 d. No procedure-related complications occurred. Stent migration to the gastric antrum occurred in one patient 1 year after the procedure, a tumor grew at the proximal end of the stent in another patient 38 d post-stent insertion.

CONCLUSION: Fluoroscopically guided peroral metal stent implantation is a safe and effective method to treat malignant gastrointestinal obstructions, and complications can be ignored based on our short-term study. Indications for this procedure should be discreetly considered because a few patients may not benefit from gastrointestinal insertion, but some benign gastrointestinal obstructions can be treated using this procedure.

Colonic stenting: an alternative to surgery in the elderly

This case report describes the management of a frail older patient presenting with a rare case of an obstructing right-sided colonic lesion, combined with complex co-morbidities. The report briefly discusses use of colonic stenting in right colonic lesions as well as palliative management of colonic tumours in general.

Mechanical comparative analysis of stents for colorectal obstruction

The goal of this work is the mechanical comparison of different types of stents for colorectal obstructions. We consider self-expanding and balloon-expanding stents made of two different materials such as stainless steel and shape memory NiTi alloy. The mechanical parameters are expansion rate, shortening, radial compression resistance, longitudinal and perimetral adaptability, and buckling resistance. This analysis results in a better understanding of global mechanical behavior and also allows better design and device selection for colonic lesions.

Repeated coaxial colonic stenting in the palliative management of benign colonic obstruction

In inflammatory bowel disease, strictures of the colon, causing bowel obstruction, is not uncommon. Usually an operative procedure can deal with these strictures. We describe a case of an unfit patient with pulmonary malignancy having a Crohn's stricture of the recto-sigmoid junction in which repeated coaxial placement of self-expanding metallic stents eliminated the need to perform an operation. This is the first report of multiple coaxial colonic stenting. It shows that there is a place for stents in selected cases of inflammatory bowel disease with a limited life expectancy and that repeated colonic stenting makes colonic stenting possible also in patients requiring stents for longer time periods.

DRUG-ELUTING BIORESORBABLE STENTS FOR VARIOUS APPLICATIONS

A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. Metallic coronary stents were first introduced to prevent arterial dissections and to eliminate vessel recoil and intimal hyperplasia associated with percutaneous transluminal coronary angioplasty. The stent application range has expanded as more experience was gained, and encouraging results have been obtained in the treatment of vascular diseases. Stents are currently used for support of additional body conduits, including the urethra, trachea, and esophagus. The rationale for bioresorbable stents is the support of a body conduit only during its healing process. The stent mass and strength decrease with time, and the mechanical load is gradually transferred to the surrounding tissue. Bioresorbable stents also enable longer term delivery of drugs to the conduit wall from an internal reservoir and abolish the need for a second surgery to remove the device. The present review describes recent advances in bioresorbable stents, focusing on drug-eluting bioresorbable stents for various applications. Controlled release of an active agent from a stent can be used to enhance healing of the surrounding tissues, to increase the implant's biocompatibility, as well as to help cure certain diseases. Because a lot of research in this field has been done by us, examples for these functions are described based mainly on developments in our laboratories.

Post-metallic stent placement bleeding caused by stent-induced ulcers

Placement of self-expandable metal stents (SEMS) is an effective mode of palliative treatment for patients with malignant gastrointestinal obstruction. Gastrointestinal mucosal bleeding complicates about 5% of placement of SEMS but is not well described. We report three cases of gastrointestinal bleeding post-SEMS placement and suggest that bleeding is caused by direct mucosal infringement by the sharp edges of the ends of the stents.

Benign duodenal strictures: treatment by means of fluoroscopically guided balloon dilation

Fluoroscopically guided balloon (15 or 20 mm in diameter) dilation was performed on eight patients with benign duodenal strictures caused by peptic ulcers (n = 6), Crohn's disease (n = 1), and postoperative adhesion (n = 1). The procedure was technically and clinically successful without complications in seven of the eight patients (88%). Duodenal perforation occurred immediately after 20-mm-diameter balloon dilation in one patient who underwent emergency surgery. During the mean follow-up of 30 months (range, 2-103 months), there was recurrence in two of the seven patients (29%) who then underwent surgery. The other five patients (71%) showed good results with no recurrence.

Use of guiding sheaths in peroral fluoroscopic gastroduodenal stent placement

Our purpose was to assess the safety and usefulness of guiding sheaths in peroral fluoroscopic gastroduodenal stent placement. Two types of guiding sheath were made from straight polytetrafluoroethylene tubes. Type A was 80 cm in length, 4 mm in outer diameter and 3 mm in inner diameter. Type B was 70 cm in length, 6 mm in outer diameter and 5 mm in inner diameter. The type A sheath was used in 18 patients in whom a catheter-guide wire combination failed to pass through a stricture. The type B sheath was used in 22 patients in whom a stent delivery system failed to pass through the stricture due to loop formation within the gastric lumen. The overall success rate for guiding a catheter-guide wire through a stricture after using the type A sheath was 89%. The overall success rate for passing a stent delivery system through a stricture after using the type B sheath was 100%. All procedures were tolerated by the patients without any significant complications. The guiding sheaths were safe and useful in peroral fluoroscopic gastroduodenal stent placement.

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

AIM: To assess the effectiveness of and complications associated with metallic stent placement for treatment of anastomotic colonic strictures.

METHODS: A 46-year-old man underging two procedures of surgery for perforation of descending colon due to a traffic accident presented with pain, abdominal distention, and inability to defecate. Single-contrast barium enema radiograph showed a severe stenosis in the region of surgical anastomosis and the patient was too weak to accept another laparotomy. Under fluoroscopic and endoscopic guidance, we placed two metallic stents in the stenosis site of the anastomosis of the patient with anastomotic colonic strictures.

RESULTS: In this case of postsurgical stenosis, the first stent relieved the symptoms of obstruction, but stent migration happened on the next day so an additional stent was required to deal with the stricture and relieve the symptoms.

CONCLUSION: This case confirms that metallic stenting may represent an effective treatment for anastomotic colonic strictures in the absence of other therapeutic alternatives.

Gastroduodenal Stent Placement: Current Status

Gastroduodenal obstruction is a preterminal event in patients with advanced malignancies of the stomach, pancreas, and duodenum. It severely limits the quality of life in affected patients due to constant emesis and associated malnutrition. Surgical gastrojejunostomy has been the traditional palliative treatment but is associated with a high complication rate, and delayed gastric emptying is a frequent problem. Gastroduodenal stent placement is a very safe and effective palliation method in patients with unresectable malignant tumors causing gastric outlet obstruction, with adequate palliation obtained in most cases. The procedure can be performed under fluoroscopic guidance or with a combination of fluoroscopic and endoscopic techniques. Advantages of gastroduodenal stent placement over surgical palliation include suitability as an outpatient procedure, more rapid gastric emptying, greater cost effectiveness, fewer complications, and improved quality of life. Covered duodenal stents are currently being evaluated and may play an increasingly important role in preventing recurrent obstruction secondary to tumor ingrowth. Moreover, simultaneous palliation of biliary and duodenal malignant strictures is possible with the use of metallic stents. Gastroduodenal stent placement is a promising new alternative for the palliation of malignant gastroduodenal obstruction.

Treatment of a benign anastomotic duodenojejunal stricture with a polytetrafluoroethylene-covered retrievable expandable nitinol stent

Temporary placement of a polytetrafluoroethylene (PTFE)-covered retrievable expandable nitinol stent was performed to treat a benign anastomotic duodenojejunal stricture that was refractory to repeated balloon dilation procedures. The procedure provided a favorable outcome for the patient and was completed without complications. This result suggests that successful treatment of benign strictures of the gastric outlet or duodenum is possible with use of retrievable stents.

Bioresorbable polymeric stents: current status and future promise

Metal stents and, more recently, polymer-coated metal stents are used to stabilize dissections, eliminate vessel recoil, and guide remodeling after balloon angioplasty and other treatments for arterial disease. Bioresorbable polymeric stents are being developed to improve the biocompatibility and the drug reservoir capacity of metal stents, and to offer a transient alternative to the permanent metallic stent implant. Following a brief review of metal stent technology, the emerging class of expandable, bioresorbable polymeric stents is described, with emphasis on developments in the authors' laboratory.

Temporary partially-covered metal stent insertion in benign esophageal stricture

AIM: To study the therapeutic efficacy of temporary partially-covered metal stent insertion on benign esophageal stricture.

METHODS: Temporary partially-covered metal stent was inserted in 83 patients with benign esophageal stricture. All the patients had various dysphagia scores.

RESULTS: Insertion of 85 temporary partially-covered metal stents was performed successfully in 83 patients with benign esophageal stricture and dysphagia was effectively remitted in all the 83 cases. The dysphagia score was 3.20 ± 0.63 (mean ± SD) and 0.68 ± 0.31 before and after stent insertion, and 0.86 ± 0.48 after stent removal. The mean diameter of the strictured esophageal lumen was 3.37 ± 1.23 mm and 25.77 ± 3.89 mm before and after stent insertion, and 16.15 ± 2.96 mm after stent removal. Follow-up time was from 1 week to 96 months (mean 54.26 ± 12.75 months). The complications were chest pain (n = 37) after stent insertion, and bleeding (n = 12) and reflux (n = 13) after stent removal.

CONCLUSION: Temporary partially-covered metal stent insertion is one of the best methods for treatment of benign esophageal stricture.

A randomised prospective comparison of the Flamingo Wallstent and Ultraflex stent for palliation of dysphagia associated with lower third oesophageal carcinoma

BACKGROUND

Covered metallic oesophageal stents offer effective palliation of malignant oesophageal strictures. However, first generation devices were associated with a high rate of migration, particularly when used in the lower oesophagus.

AIM

To compare the rate of complications and palliative effect of two newer covered metallic oesophageal stents.

PATIENTS AND METHODS

We performed a prospective randomised study using two of these newer stent designs in the treatment of malignant lower third oesophageal tumours. Fifty three patients with dysphagia due to inoperable oesophageal carcinoma involving the lower third of the oesophagus were randomly selected to receive either a Flamingo covered Wallstent (Boston Scientific Inc., Watertown, Massachusetts, USA) or an Ultraflex covered stent (Boston Scientific Inc.). Dysphagia was scored on a five point scale, recorded before stent insertion, the day after, and at least one month later at follow up. Technical success, early and late complications (perforation, migration, severe gastro-oesophageal reflux, haematemesis, and reobstruction due to tumour overgrowth) were also recorded.

RESULTS

In both stent groups, a significant improvement in dysphagia score was seen both the next day post stenting and at late follow up (p<0.05). No significant difference was seen in the improvement in dysphagia between the two groups (p>0.1). The frequency of complications encountered in the two groups was similar. Three patients in the Ultraflex group required two stents at primary stenting.

CONCLUSION

The two types of stent are equally effective in the palliation of dysphagia associated with lower third oesophageal malignancy and the complication rates associated with their use are comparable.

Balloon dilation and stent placement for esophageal lesions: indications, methods, and results

Esophageal balloon dilation and expandable stent placement are safe, minimally invasive, effective treatments for esophageal strictures and fistulas. These procedures have brought the management of dysphagia due to esophageal strictures into the field of interventional radiology. Esophageal dilation is usually indicated for benign stenoses and is technically successful in more than 90% of cases. Most patients with esophageal carcinoma are not candidates for resection; thus, the main focus of treatment is palliation of malignant dysphagia and esophagorespiratory fistulas. Esophageal stent placement, which is approved only for malignant strictures, is one of the main therapeutic options in affected patients and relieves dysphagia in approximately 90% of cases. Dedicated commercially available devices continue to evolve, each with its own advantages and limitations. Stent placement is subject to technical pitfalls, and adverse events occur following esophageal procedures in a minority of cases. Although chest pain is common and self-limited, reflux esophagitis, stent migration, tracheal compression, and esophageal perforation and obstruction require specific interventions. In many cases, these complications can be recognized and treated by the interventional radiologist with minimally invasive techniques.

Palliative stenting of malignant large bowel obstruction

OBJECTIVE: Untreated malignant large bowel obstruction is rapidly fatal. Short-term palliation of symptoms can be achieved by formation of a stoma in those patients for whom resection surgery is inappropriate. In the final months of life, a stoma represents a significant burden for both patients and carers. Palliative endoluminal stenting may therefore be an attractive alternative option for this poor prognosis group. In this paper, we examine our experience of palliative endoluminal colonic stenting. PATIENTS: Twenty patients, 11 males and 9 females of median age 81 years were referred for stenting. All had left sided colonic cancers. Ten patients had confirmed metastases on presentation, four had fixed rectal cancers and the remainder had severe comorbidity limiting surgical options. Stents were placed endoscopically using a radiologically controlled 'stent over wire' technique. RESULTS: Stenting successfully relieved the obstruction in 18 of the 20 patients attempted. In one patient the stricture could not be negotiated and the procedure was abandoned. Eleven patients have died of their disease, their median duration of palliation was 50 days (3-152 days). The rest of the patients continue in follow-up and have had 80 days median palliation (14-257 days). One stent-related complication has been observed in a patient who suffered anal pain due to fracture and migration of part of a stent into the low rectum. This complication occurred after 250 days and the distal stent fragment was removed with further symptom relief. CONCLUSION: Carefully selected patients benefit from colonic endoluminal stenting with relief of obstructive symptoms. They may be spared the potential problems associated with palliative stoma formation.

Malignant gastric outlet obstructions: treatment by means of coaxial placement of uncovered and covered expandable nitinol stents

PURPOSE

To assess whether coaxial placement of uncovered and covered expandable nitinol stents overcomes the disadvantages of the increased migration rate seen with covered stents and the tumor ingrowth seen in uncovered stents in the treatment of malignant gastric outlet obstructions.

MATERIALS AND METHODS

Two types of expandable nitinol stent were designed: an uncovered stent and a covered stent. Under fluoroscopic guidance, the uncovered and covered stents were placed coaxially with complete overlap in 39 consecutive patients with malignant gastric outlet obstruction caused by stomach cancer. Food intake capacity was graded on a scale of 0-4. Stent patency rate was estimated by the Kaplan-Meier method.

RESULTS

Technical success rate was 97% (38 of 39 patients). After stent placement, food intake capacity improved at least one grade in 36 patients. Stent migration occurred in three patients (8%), that is, partial (n = 2) or complete (n = 1) upward migration of the inner covered stent into the stomach. Two of these patients were treated by placement of an additional covered stent. During the mean follow-up period of 134 days (range, 15-569 d), 10 patients developed recurrent symptoms of obstruction with tumor overgrowth being the most common cause. Nine underwent placement of an additional covered stent with good results. The median period of primary stent patency was 157 days (mean, 278 d). The 30-, 60-, and 180-day patency rates were 97%, 91%, and 39%, respectively. Four patients (10%) died within 1 month after the procedure.

CONCLUSION

Coaxial stent placement technique seems to contribute to decreasing the migration rate of the stent and decrease the rate of recurrent obstruction by preventing or delaying tumor ingrowth.

Initial experience with Song's covered duodenal stent in the treatment of malignant gastroduodenal obstruction

PURPOSE

Initial experience with use of Song's covered duodenal stent in the treatment of malignant gastroduodenal obstruction is reported.

MATERIALS AND METHODS

Sixteen consecutive patients with malignant gastroduodenal obstruction were treated with peroral placement of Song's covered duodenal stent. The mean age was 58 years (range, 28-90 y). Gastroduodenal obstruction was caused by gastric (n = 8), metastatic (n = 2), gallbladder (n = 3), pancreatic (n = 2), or ampullary (n = 1) cancer. The disease was considered inoperable in all patients. With use of a flexible 20-F introducing system, seven fully covered, three uncovered, and 10 partially covered duodenal stents were placed under fluoroscopic guidance.

RESULTS

The technical success rate was 94% (15 of 16) with no major complications. Symptoms of gastroduodenal obstruction improved in 14 patients. Stent migration was observed in three of seven fully covered stents. Patients with migrated stents required endoscopic stent removal and placement of uncovered duodenal stents. Tumor ingrowth was observed in two thirds of uncovered stents. In the 10 procedures with partially covered duodenal stents, no migration or tumor ingrowth was observed. All patients died 1-48 weeks (mean, 12 weeks) after stent placement.

CONCLUSION

Peroral placement of Song's covered duodenal stent is a feasible and effective method of palliation in the majority of patients with malignant gastroduodenal obstruction. Migration of fully covered stents and tumor ingrowth of uncovered stents are important limitations that can be overcome with the use of a partially covered duodenal stent.