Recent Development of Techniques and Devices in Colorectal Endoscopic Submucosal Dissection

Colorectal endoscopic submucosal dissection (ESD) is now a well-established endoscopic treatment for early-stage colorectal neoplasms, especially in Asian countries, including Japan. Despite the spread of colorectal ESD, there are still situations in which achieving successful submucosal dissection is difficult. Various novel techniques and devices have been developed to overcome these difficulties, and past reports have shown that some of these strategies can be applied to colorectal ESD. We review several recent developments in the field. The techniques reviewed include the pocket creation method and traction methods and the devices reviewed include the overtube with balloon and electrosurgical knives with water-jet function. These improved techniques and devices can facilitate safer, more reliable ESDs and expand its applicability and acceptability all over the world.

Small Bowel Stent-in-Stent Placement for Malignant Small Bowel Obstruction Using a Balloon-Assisted Overtube Technique

Self-expanding metal stents are a useful therapy to palliate malignant and benign luminal gastrointestinal obstruction. Self-expanding metal stents has been widely reported for colonic, esophageal, and gastric obstruction. However, endoscopic delivery and placement to the small bowel is more challenging and difficult. This case illustrates the usefulness and technical advantages of the balloon-overtube and enteroscopy technique for the palliative treatment of neoplastic stenosis affecting the small intestine.

Overtube-related Delayed Esophageal Perforation with Mediastinitis / 대한소화기학회지

Overtube provides a conduit for the passage of endoscope into the digestive tract. Esophageal perforation with mediastinitis is a rare overtube-related complication. Until now, no reports have been published regarding the esophageal perforation which developed many months after the original procedure using the overtube. A 56-year-old female visited our hospital complaining of chest pain and back pain that began 14 days ago. The patient underwent esophageal variceal ligation using the overtube 12 months earlier. She was diagnosed with esophageal perforation with mediastinitis which extended to intervertebral and epidural space. The cause of this condition was considered to have been related to the use of overtube. Management of delayed perforation remains controversial. Although surgical management might be the preferred mode of treatment, she underwent local N-butyl 2-cyanoacrylate injection therapy and temporary stent therapy with antibiotics due to high operative risk. Herein, we report a case of overtube-related delayed esophageal perforation with mediastinitis that was successfully treated by nonoperative management.

Razor Blade Removal from the Cervical Esophagus Utilizing a Novel Modification of the Overtube / 대한소화기내시경학회지

Foreign bodies in the upper esophagus should be removed as soon as possible to avoid serious complications. These foreign bodies can penetrate the bowel wall and cause severe complications. The peristalsis of the esophagus is not strong enough to prevent it from retaining swallowed objects. Hence, perforation from a foreign body is more likely to occur in the esophagus than in the rest of the gastrointestinal tract. A razor blade is a rare foreign body of the esophagus. Its sharpness and large size make it difficult to remove. A razor blade was very firmly impacted in the esophageal wall in our case, and the razor blade had not moved from the upper esophagus. A standard overtube has limitations to remove a razor blade inside the overtube's lumen. We report here on a case of using a wedge resected overtube made it possible to successfully extract a razor blade and no serious complications occurred after extraction of the razor blade.

A new approach of estimating insertion depth with double-balloon enteroscopy / 中华消化内镜杂志

Objective The aim of this study was to evaluate the accuracy of calculating the insertion length of the overtube for estimating the insertion depth of the scope at double-balloon enteroscopy (DBE).Methods Patients with intestinal lesions found at DBE and confirmed by surgery were included. The advancing distance of the enteroscope at DBE was estimated by either cumulative length of push/pull cycle or calculation of the overall insertion length of the overtube. The accuracy of these two methods was evaluated with reference to surgery. Results Data from 51 patients who had their lesions found at DBE and treated by surgery were included in the study. DBE included 41 antegrade and 10 retrograde procedures. The average difference in the evaluation of the length of enteroscopic insertion between the two methods was 17 cm ( range 0-60 cm) on antegrade DBE and 12 cm (range 0-30 cm) on retrograde DBE. Furthermore, regardless of insertion route of DBE procedure, the mean differences between the insertion length evaluated by the two methods and surgical findings were 19 cm (range 0-50 cm) and 17 cm (range 0-60 cm), respectively, which was not significantly different ( P ＞ 0. 05 ). Conclusion The new method of calculating the length of the overtube passage is the same accurate and much simpler than the traditional method in estimating the insertion depth of the enteroscope at DBE, which is appliable in clinical practice.

Two Cases of Direct Peroral Cholangioscopy Using an Ultra-Slim Upper Endoscope after Endoscopic correction of Endoscopic after Stone Removal / 대한소화기내시경학회지

Peroral cholagioscopy is a good procedure that permits direct visualization of the biliary tree and target biopsies of lesions. However, peroral cholangioscopy with a mother-baby system requires two experienced endoscopists, and the procedure remains time consuming and expensive and the apparatus is easily broken. Therefore, an easier technique to get direct visual examination of the biliary tree is needed. Direct peroral cholangioscopy (direct POC) with using an ultra-slim upper endoscope was performed in two patients after endoscopic stone removal for diagnosing their biliary stricture. One patient had wire-guided direct POC performed and the patient was diagnosed benign biliary stricture on the proximal CBD after forcep biopsy. Another patient had overtube-assisted direct POC performed and that patient was found to have a polypoid lesion at the bifurcation. Future advances in endoscope development, as well as specifically designed accessories, are expected to increase its clinical utility.

A Case of Esophageal Perforation during Endoscopic Variceal Ligation / 대한소화기내시경학회지

Endoscopic variceal ligation(EVL) was developed to provide a safer alternative than injection sclerotherapy for treatment of bleeding esophageal varices. EVL adds a new indication that will significantly increase the use of overtubes. overtube itself may have a role in predisposing to esophageal perforation but only one report has been published regarding an esophageal perforation related to the placement of an overtube. Recently, we experienced a case of esophageal perforation caused by overtube placement during endoscopic variceal ligation. So we report this case with review of relevant literatures.

A Novel Method for Overtube Placement in Endoscopic Variceal Ligation / 대한소화기내시경학회지

Endoscopic variceal ligation (EVL) is effective for the management of bleeding esophageal varices, and its use is widespread now. EVL necessitates the use of overtubes. Two primary techniques have been used for overtube placement; one is with endoscope, and the other is with bougie dilator. Overtube placement with endoseope is not without risk. There are reportd of esophageal or pharyngeal laceration or perforation. Overtube placement with bougie dilator circumvents this risk, but it is rather cumbersome to use. The authors devised a safe and easy method for overtube placement, and applied it to a number of patients to test its safety and convenience. First, overtube-dilator assembly was prepared as follows. A Rigiflex achalasia dilator (balloon 30mm OD, 10cm length; Microvasive Co) was lubricated and inserted into the overtube. A tenth of the balloon tip was protruded out of the overtube, then the balloon was insufflated with air at 10-15 psi. Second, standard endoscopy was performed, followed by placement of guide wire in the stomach. Overtube-dilator assembly was lubricated and introduced over the wire as a rail. Once the overtube was properly positioned, the balloon was deflated, and the balloon and wire were removed as a whole, which completed overtube placement. For 65 patients with esophageal variceal bleeding, 82 procedures of EVL were performed using the new technique. Overtube-dilator assembly was easy to prepare and handle. This technique added little time to the procedure and minimizes patients discomfort. No patient suffered major complications such as bleeding, laceration or perforation. This novel method for overtube placement was safe and convenient for use in EVL. It can also be applied to other procedures using overtube such as endoscopic foreign body removal.