Determining scope position during colonoscopy without use of ionizing radiation or magnetic imaging: the enhanced mapping ability of the NeoGuide Endoscopy System.

BACKGROUND: Knowledge of the position and shape of the endoscope could overcome many challenges of performing colonoscopy, e.g., loop formation. A novel computer-assisted colonoscope (NeoGuide Endoscopy System) delivers a real-time, three-dimensional map of the tip position and insertion tube shape in addition to the video image of the colon lumen. The aim of this study is to evaluate the mapping capabilities of the NeoGuide Endoscopy System in terms of colonic looping, insertion depth, tip position, and tip angle formation. METHODS: Ten endoscopists with various levels of experience were each shown 70 map images generated by the NeoGuide endoscopy system in a benchtop anatomical colon model. First endoscopists were asked to determine the tip angle based on the map image and the system's corresponding tip positioning aid (20 images). In the second part they had to identify the scope-tip position in the colon model (40 images). In the third part ten images were presented for identification of colonic loops. RESULTS: The tip angle was correctly identified in 99% (198/200) of images. Using only the map images the scope position was accurately determined in 87.5% (350/400). Identification of colonic looping of the scope was appropriate in 99% (99/100). Overall accuracy was 92.4%, and overall positive predictive value was 94.9%. CONCLUSION: Three-dimensional map images generated by the NeoGuide endoscopy system provide accurate information regarding tip position, insertion tube position, and colonic looping.

Self-expanding metal stents for the palliation of malignant gastric outlet obstruction in patients with peritoneal carcinomatosis.

AIM: To evaluate the efficacy of self-expanding metal stents (SEMS) for the palliation of malignant gastric outlet obstruction in patients with and without peritoneal carcinomatosis (PC). METHODS: We performed a retrospective analysis of 62 patients who underwent SEMS placement for treatment of malignant gastroduodenal obstruction at our hospital over a six-year period. Stents were deployed through the scope under combined fluoroscopic and endoscopic guidance. Technical success was defined as successful stent placement and expansion. Clinical success was defined as an improvement in the obstructive symptoms and discharge from hospital without additional parenteral nutrition. According to carcinomatosis status, patients were assigned into groups with or without evidence of peritoneal disease. RESULTS: In most cases, obstruction was caused by pancreatic (47%) or gastric cancer (23%). Technical success was achieved in 96.8% (60/62), clinical success in 79% (49/62) of all patients. Signs of carcinomatosis were identified in 27 patients (43.5%). The diagnosis was confirmed by pathology or previous operation in 7 patients (11.2%) and suspected by CT, MRI or ultrasound in 20 patients (32.2%). Presence of carcinomatosis was associated with a significantly lower clinical success rate compared to patients with no evidence of peritoneal disease (66.7% vs 88.6%, P = 0.036). There was no significant difference in overall survival between patients with or without PC (median 48 d vs 70 d, P = 0.21), but patients showed significantly longer survival after clinical success of SEMS placement compared to those experiencing clinical failure (median 14.5 d vs 75 d, P = 0.0003). CONCLUSION: Given the limited therapeutic options and a clinical success rate of at least 66.7%, we believe that SEMS are a reasonable treatment option in patients with malignant gastric outlet obstruction with peritoneal carcinomatosis.

Exclusion mapping of the genetic predisposition for cervical artery dissections by linkage analysis.

Skin biopsies from a patient with a dissection of the left internal carotid artery and from four of his children were analyzed by electron microscopy. The index patient and three children showed mild but regular electron microscopic connective tissue aberrations. They were considered as carriers of an unknown autosomal dominant mutation. Thirty-four candidate genes involved in the biosynthesis of the extracellular matrix were excluded by genetic linkage analysis as possible sites of a disease-causing mutation in this family (logarithm of odds [LOD]-score less than -2.0).