Imaging technologies in gastrointestinal endoscopy have advanced greatly over the past few decades. Molecular imaging is an additional innovation to conventional imaging methods and allows visualization of the localization, function, and characteristics of target lesions, especially cancers. To realize endoscopic molecular imaging, there are three prerequisites : first, more target-specific and highly sensitive biomarkers for clinical use ; second, fluorochromes that have a high affinity for their markers and can produce a distinct signal ; and third, equipment to visualize the indicator at high resolution in real time. Endoscopic molecular imaging can be used for cancer screening and surveillance and can also provide important information for deciding treatment strategies and evaluating their effectiveness during therapy. Endoscopic molecular imaging will play a central role in gastrointestinal oncology in the near future.

An 83-year-old woman was taken to our hospital by ambulance because of hematemesis. Laboratory examination revealed high blood levels of lactate (35mg/dL), creatinine (2.1mg/dL) and glucose (249mg/dL). Thoracoabdominal CT scans showed a large esophageal hernia, presenting with upside-down stomach and mesenteroaxial volvulus. Urgent endoscopy revealed diffuse black mucosa in the middle and lower esophagus, so-called “black esophagus”. The abnormal rotation returned to normal by performing the stretching method with a duodenoscope. On the following day, the esophageal lesion was remarkably improved. When encountering a case of upside-down stomach with acute necrotizing esophagitis, endoscopic de-rotation should be immediately considered.

The patient was a 74-year-old woman. During hospitalization for dementia, she accidentally swallowed a watch and was brought to our endoscopy department. A simple abdominal X-ray visualized a foreign body in the stomach, and we attempted to extract it using an upper gastrointestinal endoscope. The watch had a hard, elastic metal band measuring 5 cm in diameter and was relatively heavy. It was difficult to extract the watch with devices available at our hospital. Therefore, using grasping forceps inserted through a forceps port of the endoscope, we grasped a retrieval net. One corner of the retrieval net was attached to the endoscope ; then, using the grasping forceps, we passed the retrieval net through the watch band, and released the retrieval net. Then, we grasped it again from outside the band to form a ring with the retrieval net, the grasping forceps, and the endoscope, and thereby succeeded in extracting the watch from the patient’s gastrointestinal tract. This technique is considered to be useful and minimally invasive for extracting heavy, ring-shaped foreign bodies in the gastrointestinal tract.

We experienced a case of ulcerative colitis complicated with cerebral sinus thrombosis. A 52-year-old male with ulcerative colitis was hospitalized because of hemiplegia of the right upper limb. Computed tomography revealed a high-density area in the parietal lobe. Magnetic resonance imaging disclosed a high-signal-intensity area in the frontal lobe on T2 and diffusion weighted image. Cerebral angiography revealed an obstruction of the superior sagittal sinus. Cerebral sinus thrombosis was diagnosed. Anticoagulant therapy was administered for seven days, but his symptoms and MRI findings did not improve. Therefore, urgent surgical decompression was performed and he survived. Ulcerative colitis complicated with cerebral sinus thrombosis is rare in Japan.

An 84-year-old woman was admitted to our hospital for acute pancreatitis and cholangitis. Imaging examinations revealed a sessile nodule just above localized adenomyomatosis in the gallbladder fundus. Cholecystectomy with gallbladder bed resection was performed under the diagnosis of gallbladder carcinoma. Histopathologically, the sessile nodule was focal tubular adenocarcinoma in tubular adenoma of the pyloric gland type with no invasion, and the adenoma extended into a Rokitansky-Aschoff sinus in the localized adenomyomatosis. Neoplastic cells had mucus in the cellular cytoplasm. There was no strong evidence that suggested a relationship between carcinoma and adenomyomatosis. Acute pancreatitis and cholangitis may have occurred due to the passage of a neoplastic tissue fragment through the papilla, because there was no evidence of stone, bleeding, and mucus with high viscosity in the preoperative imaging examinations and the resected specimen.

Purpose : The variation in serum electrolyte concentration after the use of polyethylene glycol containing ascorbic acid and electrolytes (PEG-ASC) for bowel preparation in dialysis patients was examined. Method : Blood samples were obtained from dialysis patients before taking PEG-ASC and after colonoscopy. Results : In the group of patients not under hyperkalemia remedy (12 patients), there was a significant increase in the serum potassium concentration after taking PEG-ASC (4.5±0.4mEq/L vs. 4.9±0.7mEq/L, before vs. after taking PEG-ASC, P＝0.012). Conclusion : When dialysis patients undergo oral whole bowel irrigation with PEG-ASC, it is important to monitor their potassium concentration, and a potassium-lowering drug may need to be administered.

Endoscopic submucosal dissection (ESD) allows en bloc resection of large gastrointestinal neoplasms regardless of their size. However, ESD is difficult to perform and it is associated with a longer procedure time and higher risk of complications such as perforation than endoscopic mucosal resection (EMR). To address this difficulty, several traction methods have been introduced to facilitate ESD procedure.

We designed a traction device called the S-O clip (Zeon Medical Co., Ltd., Tokyo, Japan) and reported it previously. The S-O clip consists of a metallic clip attached to the end of a spring, which is connected at its other end to a nylon loop. It can be passed through an endoscope instrument channel and can easily pull a lesion at any location up without withdrawing the endoscope. We describe the basic and recommended usage of the S-O clip.

1.　A circumferential incision around the tumor in the submucosal layer is performed.

2.　After separation of the tumor from the surrounding normal mucosa, an S-O clip is attached to the edge of the exfoliated mucosa.

3.　A regular clip is used to grasp the distal nylon loop attached to the S-O clip and then the regular clip is inserted and applied to the colon wall opposite the lesion, enabling traction and therefore opening the resection margin.

4.　The traction applied by the S-O clip pulls on the edge of the lesion, allowing the cutting line in the submucosal layer to be visualized and resulting in safe and successful en bloc dissection.

5.　After dissection, the nylon loop is cut with a knife, and the specimen is brought out using the forceps. The endoscope is not withdrawn during the entire procedure.

S-O clip-assisted ESD is safe and effective for en bloc resection of large superficial neoplasms in the colorectum.

Endoscopic management of occluded metallic stents deployed for malignant hilar biliary stricture is technically demanding. Understanding the characteristics of devices such as guidewires, catheters, and stents, and handling these devices skillfully are essential for successful management. The passage of catheters and plastic stents (PS) through the mesh of metallic stents (MS) is the most difficult of all procedures for multiple occluded MS that had been deployed by the stent-in-stent method, and requires precise and careful maneuvering of the endoscope and other devices. The order of PS deployment into the occluded MS is also important. The order of PS deployment has to be same as that of the previous MS deployment. Skilled techniques of not only endoscopists but also their assistants are necessary for the successful management of multiple occluded MS deployed at the hilar portion. Therefore, it is important for endoscopists to become skilled in maneuvering guidewires in daily examinations.

Background and Aim : Prophylactic clipping has been widely used to prevent post-procedural bleeding in colon polypctomy. However, its efficiency has not been confirmed and there is no consensus on the usefulness of prophylactic clipping. The aim of the present study was to evaluate the preventive effect of prophylactic clipping on post-polypectomy bleeding.

Methods : A multicenter randomized controlled study was conducted from January 2012 to July 2013 in Japan. Patients who had polyps ＜２cm in diameter were divided into a clipping group and a non-clipping group by cluster randomization. After endoscopic polypectomy, patients allocated to the clipping group underwent prophylactic clipping, whereas the procedure was completed without clipping in patients allocated to the nonclipping group. Occurrence of post-polypectomy bleeding was compared between the two groups.

Results : Seven hospitals participated in this study. A total of 3,365 polyps in 1,499 patients were evaluated. The clipping group consisted of 1,636 polyps in 752 patients, and the non-clipping group consisted of 1,729 polyps in 747 patients. Postpolypectomy bleeding occurred in 1.10％ (18/1,636) of the cases in the clipping group, and in 0.87％ (15/1,729) of those in the nonclipping group. The difference was -0.22％ (95％ confidence interval ［CI］ : -0.96, 0.53). Upper limit of the 95％ CI was lower than the noninferiority margin (1.5％), and we could thus prove non-inferiority of non-clipping against clipping.

Conclusion : Prophylactic clipping is not necessary to prevent post-polypectomy bleeding for polyps ＜２cm in diameter.