Stefan Goelder

Endoscopic treatment of Zenker’s diverticulum with the stag beetle knife (sb knife) – feasibility and follow-up

Abstract Background and aims: Flexible endoscopic treatment of symptomatic Zenker’s diverticulum (ZD) is an established treatment option. This study reports the first large cohort of ZD patients treated with the stag beetle knife (sb knife, a new scissor-like device) regarding feasibility, safety, and sustainability of mucomyotomy using this technique. Methods: From August 2013 to January 2016, n = 52 patients (pts) were treated at Klinikum Augsburg, a tertiary referral center, with the sb knife junior or standard. For stability and safety, the septum is fixed with a soft overtube before intervention. Symptoms were analyzed before and at 1 and 6 months past intervention using an extensive questionnaire of dysphagia, odynophagia, regurgitation, chronic cough, state of health, and complications. Results: The mean size of ZD was 3 cm (1–5 cm). Forty-seven out of 52 (90.4%) patients received one treatment session. The mean procedure time was 32 min (18–60 min). In 10 procedures (17%), a clip was placed at the bottom of the resection line. No major complications (e.g., perforation, mediastinitis) occurred. Five patients (9.6%) required a second treatment after a mean of 7 months (3–13) due to symptomatic recurrence. One patient was lost to further follow-up after one month with no or rare complaints. One patient had a third treatment (1.9%) without complications. During a mean follow-up of 16 months (2–31), the dysphagia score improved from 2 (1–4) prior of treatment to 1 (0–4), odynophagia, regurgitation, and chronic cough were no longer reported in the asymptomatic patients at all. Conclusions: Flexible endoscopic treatment of ZD with the sb knife and overtube is effective, safe, and has lasting effects with a relatively low recurrence rate.

Endoscopic hemostasis state of the art - Nonvariceal bleeding

New endoscopic techniques for hemostasis in nonvariceal bleeding were introduced and known methods further improved. Hemospray and Endoclot are two new compounds for topical treatment of bleeding. Initial studies in this area have shown a good hemostatic effect, especially in active large scale oozing bleeding, e.g., tumor bleedings. For further evaluation larger prospective studies comparing the substanced with other methods of endoscopic hemostasis are needed. For localized active arterial bleeding primary injection therapy in the area of ​​bleeding as well as in the four adjacent quadrants offers a good method to reduce bleeding activity. The injection is technically easy to learn and practicable. After bleeding activity is reduced the bleeding source can be localized more clearly for clip application. Today many different through-the-scope (TTS) clips are available. The ability to close and reopen a clip can aid towards good positioning at the bleeding site. Even more important is the rotatability of a clip before application. Often multiple TTS clips are required for secure closure of a bleeding vessel. One model has the ability to use three clips in series without changing the applicator. Severe arterial bleeding from vessels larger than 2 mm is often unmanageable with these conventional methods. Here is the over-the-scope-clip system another newly available method. It is similar to the ligation of esophageal varices and involves aspiration of tissue into a transparent cap before closure of the clip. Thus a greater vascular occlusion pressure can be achieved and larger vessels can be treated endoscopically. Patients with severe arterial bleeding from the upper gastrointestinal tract have a very high rate of recurrence after initial endoscopic treatment. These patients should always be managed in an interdisciplinary team of interventional radiologist and surgeons.

Chromoendoscopy in magnetically guided capsule endoscopy

BackgroundDiagnosis of intestinal metaplasia and dysplasia via conventional endoscopy is characterized by low interobserver agreement and poor correlation with histopathologic findings. Chromoendoscopy significantly enhances the visibility of mucosa irregularities, like metaplasia and dysplasia mucosa. Magnetically guided capsule endoscopy (MGCE) offers an alternative technology for upper GI examination. We expect the difficulties of diagnosis of neoplasm in conventional endoscopy to transfer to MGCE. Thus, we aim to chart a path for the application of chromoendoscopy on MGCE via an ex-vivo animal study.MethodsWe propose a modified preparation protocol which adds a staining step to the existing MGCE preparation protocol. An optimal staining concentration is quantitatively determined for different stain types and pathologies. To that end 190 pig stomach tissue samples with and without lesion imitations were stained with different dye concentrations. Quantitative visual criteria are introduced to measure the quality of the staining with respect to mucosa and lesion visibility. Thusly determined optimal concentrations are tested in an ex-vivo pig stomach experiment under magnetic guidance of an endoscopic capsule with the modified protocol.ResultsWe found that the proposed protocol modification does not impact the visibility in the stomach or steerability of the endoscopy capsule. An average optimal staining concentration for the proposed protocol was found at 0.4% for Methylene blue and Indigo carmine. The lesion visibility is improved using the previously obtained optimal dye concentration.ConclusionsWe conclude that chromoendoscopy may be applied in MGCE and improves mucosa and lesion visibility. Systematic evaluation provides important information on appropriate staining concentration. However, further animal and human in-vivo studies are necessary.

Anthocyanins Prevent Colorectal Cancer Development in a Mouse Model

Background: Colorectal cancer is the main leading cause of cancer-related deaths worldwide. Present data suggest that plant-derived anthocyanins have anti-inflammatory and chemopreventive properties. This study was aimed at evaluating the effect of an anthocyanin-rich extract from bilberries on colorectal tumour development and growth in the administration of azoxymethan (AOM)/dextran sodium sulfate (DSS) mouse model. Methods: Colonic carcinogenesis was induced by AOM and DSS 3 or 5%, respectively, in 50 female Balb/c mice. Mice received either normal food (controls) or a diet containing either 10 or 1% anthocyanin-rich bilberry extract. Colonoscopy took place at week 4 and 9 after initiation of carcinogenesis. After termination at week 9, colon samples were analysed macroscopically and microscopically. Results: Mice receiving 10% anthocyanins showed significantly (p < 0.004) less reduced colon length (12.1 cm [8.5-14.4 cm]) as compared to controls (11.2 cm [9.8-12.3]) indicating less inflammation. Mice fed with 10% anthocyanin-rich extract revealed significantly less mean tumour numbers (n = 1.2) compared to control (n = 14) and anthocyanin 1% treated mice (n = 10.6, p < 0.001). Conclusion: Anthocyanins prevented the formation and growth of colorectal cancer in AOM/DSS-treated Balb/c mice. Further studies should investigate the mechanisms of how anthocyanins influence the development of colorectal cancer.

Hexaminolevulinate- Induced Fluorescence Endoscopy in Patients with Rectal Adenoma and Cancer

BACKGROUND Fluorescence endoscopy is a promising new method for detection and treatment of premalignant and malignant lesions. The aim of this pilot study was to investigate the feasibility of hexaminolevulinate-based photodetection of rectal adenoma and cancer, including safety, dose finding, and efficacy. METHODS Ten patients with known rectal adenoma or cancer were sensitized by instillation of 3.2 mM of hexaminolevulinate as an enema. Fluorescence endoscopy was performed after retention of the enema for 30 to 60 minutes, followed by a rest time of up to 30 minutes before endoscopy. Biopsy specimens were taken from fluorescent and non-fluorescent areas and fluorescence microscopy studies were performed to assess the distribution of protoporphyrin IX fluorescence in different tissue layers. Adverse events were reported by direct questioning of all patients; skin photosensitivity, changes in biochemical tests of liver function, blood pressure and heart rate, and the occurrence of GI symptoms (nausea, vomiting) were recorded for 5 patients. OBSERVATIONS Hexaminolevulinate-induced fluorescence endoscopy produced selective fluorescence of all rectal adenomas with intraepithelial neoplasia. For rectal cancer, there was only weak fluorescence or none at all. No hexaminolevulinate-induced side effect was observed. In two patients, fluorescence differentiated adenomas and hyperplastic polyps. CONCLUSIONS Hexaminolevulinate-based fluorescence endoscopy (3.2 mM administered as an enema) in patients with rectal cancer and adenoma was well tolerated and produced no significant skin sensitivity or other side effects. The optimal duration of application is 30 to 45 minutes, with a rest time of 30 minutes. Selective fluorescence of adenoma with intraepithelial neoplasia suggests that hexaminolevulinate-based fluorescence endoscopy may be useful for detection of premalignant lesions.