Endoscopic full-thickness resection and defect closure in the colon

Performance of the OTSC System in the endoscopic closure of iatrogenic gastrointestinal perforations: a systematic review

BACKGROUND

Reliable closure is a prerequisite for conventional and innovative endoscopic procedures, such as NOTES. The purpose of this study is the systematic evaluation of the procedural and clinical success rates in closure of iatrogenic gastrointestinal perforations and acute anastomotic leaks by means of the over-the-scope-clip system (OTSC(®)).

DESIGN

PubMed and other sources were searched systematically for clinical and preclinical research on the evaluation of the OTSC System for closure of gastrointestinal perforations and leaks. Appraisal of studies for inclusion and data extraction was performed independently by two reviewers using an a priori determined data extraction grid. Major endpoints to be extracted were data on procedural success (successful clip application) and clinical access (durable closure of defect without secondary adjunct therapy).

RESULTS

A total of 17 clinical research articles/abstracts and 22 preclinical research articles/abstracts were identified. The examined clinical studies comprised case series and clinical single-arm studies. The reviewed studies revealed a consistently high mean rate of procedural success of 80-100 % and durable clinical success of 57-100 %. An identified major drawback preventing successful clip application was occurrence of fibrotic or inflamed lesion edges. Usage of the OTSC System was accompanied by neither major clip-related nor application-related complication. In experimental settings, closure of larger perforations and gastric access sites of NOTES or endoscopic full-thickness resection were achieved with high rates of success.

CONCLUSIONS

Because randomized, clinical trials are not available in this field of indication, the evaluation is based on small case series. Nevertheless, by pooling all experience gained, we conclude that endoscopic closure of iatrogenic gastrointestinal perforations and acute anastomotic leaks by means of the OTSC System is a safe and effective method.

Full-field optical coherence microscopy is a novel technique for imaging enteric ganglia in the gastrointestinal tract

BACKGROUND

Noninvasive methods are needed to improve the diagnosis of enteric neuropathies. Full-field optical coherence microscopy (FFOCM) is a novel optical microscopy modality that can acquire 1 μm resolution images of tissue. The objective of this research was to demonstrate FFOCM imaging for the characterization of the enteric nervous system (ENS).

METHODS

Normal mice and EdnrB(-/-) mice, a model of Hirschsprung's disease (HD), were imaged in three-dimensions ex vivo using FFOCM through the entire thickness and length of the gut. Quantitative analysis of myenteric ganglia was performed on FFOCM images obtained from whole-mount tissues and compared with immunohistochemistry imaged by confocal microscopy.

KEY RESULTS

Full-field optical coherence microscopy enabled visualization of the full thickness gut wall from serosa to mucosa. Images of the myenteric plexus were successfully acquired from the stomach, duodenum, colon, and rectum. Quantification of ganglionic neuronal counts on FFOCM images revealed strong interobserver agreement and identical values to those obtained by immunofluorescence microscopy. In EdnrB(-/-) mice, FFOCM analysis revealed a significant decrease in ganglia density along the colorectum and a significantly lower density of ganglia in all colorectal segments compared with normal mice.

CONCLUSIONS & INFERENCES

Full-field optical coherence microscopy enables optical microscopic imaging of the ENS within the bowel wall along the entire intestine. FFOCM is able to differentiate ganglionic from aganglionic colon in a mouse model of HD, and can provide quantitative assessment of ganglionic density. With further refinements that enable bowel wall imaging in vivo, this technology has the potential to revolutionize the characterization of the ENS and the diagnosis of enteric neuropathies.

Endoscopic closure of gastrointestinal defects with an over-the-scope clip device. A case series and review of the literature

BACKGROUND

The over-the-scope clip (OTSC) is a novel endoscopic tool used in the non surgical treatment of gastrointestinal perforations, fistula, and anastomotic leaks.

AIMS

The aim of the present study was to evaluate the therapeutic efficacy of this new endoscopic device on anastomotic postsurgical leak and fistulas or GI perforation in a tertiary referral center.

PATIENTS AND METHODS

The study group consisted of nine patients (three female, six male, age: 22-65 years). The indications were anastomotic leak in five patients, fistula in three patients, and perforation in one patient. Atraumatic version of OTSCs with medium sized caps, twin graspers and anchor were used. All of the patients were treated with only one OTSC. None of the patients underwent additional endoscopic treatments.

RESULTS

The median size of the defects were 15 mm (range 5-20 mm). OTSC was favourable in five of nine patients (three with leak, and one with fistula and perforation, each). OTSC could not be deployed or partially closed the defect in the remaining four patients because of fibrosis at the edges of the defect. Excluding the case with perforation, the median time elapsed between the diagnosis and the placement of OTSC was 35 days (range: 20-80) in the successful group and 70 days (range: 38-94) in the unsuccessful group. There were no complications due to the OTSC application or the applicator cap.

CONCLUSIONS

OTSC is a safe and effective device for closure of perforations and leaks. However therapeutic efficacy is lower in cases with fistulas mainly due to associated fibrosis at the borders.

Performance of the OTSC System in the endoscopic closure of gastrointestinal fistulae--a meta-analysis

BACKGROUND

Conventional endoscopic treatment options for closure of gastrointestinal fistulae are impaired by several limitations and therefore yield high rates of recurrence. Aim of the study is the evaluation of the primary-technical and secondary-clinical success rates in closure of gastrointestinal fistulae by means of the OTSC System.

DESIGN/METHODS

The database Medline was systematically searched for primary research on the evaluation of the OTSC System in closure of gastrointestinal fistulae. Appraisal of studies for inclusion and data extraction were performed independently by two reviewers using an a priori determined data extraction grid.

RESULTS

A total of 19 primary research articles were identified. The examined studies comprised case reports as well as case series and clinical single-arm studies (n = 7) with a limited number of participants. Reviewed studies revealed a high rate of procedural success (mean 84.6%; 95% confidence interval 66.6 to 93.8%) and durable clinical success (mean 69.0%; 95% confidence interval 51.8 to 82.2%). Failed attempts and incomplete closures were mainly ascribed to the challenging effort of treating highly fibrotic chronic fistulae.

CONCLUSION

Endoscopic closure of gastrointestinal fistulae by means of the OTSC System is a safe and effective method.

Endoscopic full-thickness resection of submucosal gastric tumors

BACKGROUND AND AIMS

Endoscopic full-thickness resection (EFTR) is a minimally invasive method for en bloc resection of gastrointestinal lesions, such as early cancer or submucosal tumor. The aim of this pilot study was to evaluate a novel EFTR prototype device for full-thickness resection of the gastric wall containing artificial submucosal lesions.

METHODS

Six artificial submucosal tumors were surgically created in the gastric submucosa by implanting 8-mm cork beads in anesthetized pigs. EFTR of the lesions was attempted using a prototype device which consists of a large transparent plastic cap, loaded onto the tip of the endoscope, into which the submucosal lesion and the surrounding gastrointestinal wall can be pulled by using suction, a grasping forceps, or a dedicated anchoring device. An over-the-scope clip (OTSC) can be deployed underneath the submucosal lesion and a pre-loaded snare is used for EFTR above the OTSC.

RESULTS

The median procedure time was 15 min (interquartile range 11-22). Successful resection of the artificial submucosal lesion was achieved in 4/6 (67%) cases. Successful EFTR of the gastric wall was achieved in 3/6 (50%) cases. In all cases, the OTSC closed the EFTR site completely.

CONCLUSIONS

Gastric EFTR using the novel EFTR prototype device is feasible in a live animal model. The technique can achieve a full-thickness gastric wall and submucosal tumor resection with reliable closure of the gastric wall, but further refinements of the technique and device are necessary in order to reliably resect submucosal lesions, especially larger ones.

Endoscopic full-thickness resection in the colon by using a clip-and-cut technique: an animal study

BACKGROUND

Although endoscopic resection techniques have been established for definitive therapy of mucosal neoplasia, complete histopathological assessment or resection of subepithelial lesions is not reliably possible.

OBJECTIVE

To overcome these limitations, a novel endoscopic full-thickness resection (EFTR) and closure technique was developed.

DESIGN

Animal survival study.

ANIMALS

Eight female domestic pigs.

INTERVENTIONS

Two-centimeter artificial distal colonic lesions were created endoscopically. EFTR of the lesions was attempted using a prototype device, which consists of a large transparent plastic cap with a preloaded snare and a modified over-the-scope clip. After the procedure, half of the animals were killed after 7 days, and the other half after 28 days.

MAIN OUTCOME MEASUREMENTS

Complete resection (all markings included in the specimen), technical success, complication rates, and wound healing on follow-up autopsy and histology.

RESULTS

EFTR of healthy colonic tissue was possible in all cases; 2 additional clips had to be placed for complete closure in 1 case. In 1 animal, the preloaded closure failed, and the animal was prematurely killed. All other animals had an uneventful postoperative course. Necropsy and histopathological evaluation demonstrated well-healed resection sites with no evidence of intra-abdominal infection or inadvertent organ inclusion.

LIMITATIONS

Animal model, resection of healthy tissue.

CONCLUSION

This novel device allows for reliable full-thickness resection and closure of 2-cm specimens of the colonic wall in a single procedure as well as reliable wound healing of EFTR defects.

New method of endoscopic full-thickness resection: a pilot study of non-exposed endoscopic wall-inversion surgery in an ex vivo porcine model

The indications for endoscopic full-thickness resection (EFTR) are limited because transmural communication during the entire procedure, causing tumor dissemination into the abdominal space, is inevitable. We invented a new method of EFTR without transmural communication, and explored its feasibility in an ex vivo porcine model. Three explanted porcine stomachs were used. First, markings around a model lesion were made with a flexible endoscope, and 0.9% normal saline with indigocarmine was injected into the submucosa around the markings. Second, a circumferential sero-muscular incision was made from the outside with an electrocautery knife, guided by the color of the submucosal injection and intragastric navigation with the endoscope. Third, the muscle layer was linearly sutured with the lesion inverted into the inside. Finally, a circumferential muco-submucosal incision was made with an electrocautery knife employed with the endoscope. The method was performed for 3 lesions (1 anterior wall, 1 lesser curve, and 1 posterior wall of the gastric body), and all lesions were successfully resected in en-bloc fashion. The mean size of the resected specimen was 4.5 cm in diameter. Neither perforation nor apparent air leakage was seen during or after the resection. Non-exposed endoscopic wall-inversion surgery (NEWS) is thought to be effective as a minimally invasive, and minimal-size endoluminal surgery for gastric submucosal tumors with or without ulceration, or even node-negative early gastric cancer that is difficult to resect by endoscopic submucosal dissection.

Endoluminal full-thickness resection of GI lesions: a new device and technique

Full-thickness resection techniques are of growing interest in the field of endoscopic removal of tumors or their precursors in the digestive tract. A new dedicated full-thickness resection device has been developed based on the combination of the OTSC clip, an enlarged resection cap and an integrated snare. The device prototype allows combined resection of all gastrointestinal organ wall layers in one maneuver, up to a size of 3 x 3 cm. The device has been pre-clinically tested to demonstrate feasibility of full-thickness resection in the colon. Two clinical cases have been performed successfully to date.

Colonic endoscopic full-thickness biopsies: from the neuropathological analysis of the myenteric plexus to the functional study of neuromuscular transmission

BACKGROUND

Better understanding of the pathophysiological mechanisms involved in severe dysmotility disorders is crucial to improve patient management and identify novel therapeutic targets. Recent studies suggested that endoscopic full-thickness biopsies (eFTBs) could be developed as an alternative to surgical biopsies. However, currently it remains unknown whether eFTBs would allow myenteric plexus analysis on whole mounts and the evaluation of neuromuscular transmission.

OBJECTIVE

To determine with eFTB specimens the ability to analyze on whole mounts the key parameters of the myenteric plexus, ie, ganglia and neurons, and to perform functional evaluation of neuromuscular transmission.

DESIGN

An experimental pilot study in 6 pigs was conducted in accordance with French institutional guidelines.

INTERVENTION

Under general anesthesia, pigs underwent a rectosigmoidoscopy. In each pig, an eFTB was performed at 25, 30, and 35 cm from the anal margin with an EMR-based technique. Tissue specimens were immediately processed for immunohistochemical and/or functional ex vivo analysis of neuromuscular transmission. In 2 pigs, over-the-scope clips were used to seal the perforation.

MAIN OUTCOME MEASUREMENTS

Feasibility of obtaining specimens containing myenteric plexus and muscularis propria, quantitative and standardized immunohistochemical evaluation of ganglia and myenteric neurons, ex vivo assessment of neuromuscular transmission and its pharmacology, and closure rate (ancillary study).

RESULTS

Adequate tissue specimens were obtained in 100% of the procedures, on average, in 6±2 minutes. Immunohistochemical analysis of a whole mount of the myenteric plexus showed that each eFTB contained 14±5 ganglia and 1562±1066 myenteric neurons. In circular muscle strips, electrical field stimulation or exposure to a pharmacological agent induced a specific tissue response. A successful closure was achieved in 50% of cases.

LIMITATIONS

Nonsurvival study; safety of the procedure needs to be specifically assessed and compared with recently published data.

CONCLUSIONS

We demonstrate, for the first time, that full-thickness biopsy specimens obtained by using an endoscopic approach allow the performance of a precise study of the ENS phenotype on whole mounts of the myenteric plexus and the performance of functional studies such as evaluation of neuromuscular transmission. However, further studies are warranted to identify the optimal and safest endoscopic procedure before application of eFTB in humans.

Endoscopic closure of GI fistulae by using an over-the-scope clip (with videos)

BACKGROUND

Preclinical studies have demonstrated the over-the-scope clip (OTSC) to be feasible and safe for closure of gastric, duodenal, and colonic perforations. A retrospective clinical study demonstrated the feasibility and preliminary safety of the OTSC for the treatment of GI bleeding and closure of acute GI perforations.

OBJECTIVE

Because the OTSC allows rapid and easy endoscopic organ wall closure, we hypothesized that it might be a useful tool to close GI fistulae.

DESIGN

Case series.

SETTING

Academic medical center.

PATIENTS

Four consecutive patients with GI fistulae.

INTERVENTIONS

In all patients, a 12-mm OTSC, in combination with the dedicated twin grasper, anchor device, or endoscopic suction, was used to facilitate endoscopic closure.

MAIN OUTCOME MEASUREMENTS

In 2 cases, OTSCs allowed complete closure of a posttraumatic esophagopulmonary fistula and a chronic gastrocutaneous fistula. Leak tests and follow-up examination demonstrated complete leakproof closures. In 1 esophagopulmonary fistula and 1 jejunocutaneous fistula, the initial closure attempts using OTSCs were not successful because of chronic fibrotic changes and scarring at the fistula site. Both OTSCs were removed by using an endoscopic grasping forceps. The mean procedure time was 54 minutes (range 24-93 minutes). There were no procedure-related complications.

LIMITATIONS

Small sample size.

CONCLUSIONS

The OTSC seems to be a feasible device to close chronic fistulae of the GI tract. It can achieve leakproof, full-thickness closure of transmural defects. Nevertheless, in circumstances of severe fibrosis and scarring, complete incorporation of the defect into the applicator cap and successful OTSC application might not be possible.