Toshiki Sugawara

Impact of a transparent hood on the performance of total colonoscopy : a randomized controlled trial

BACKGROUND Clinical demand for total colonoscopy (TCS) is increasing. Improvement of the cecal intubation rate and shortening of the examination time would expand the capacity for TCS. OBJECTIVE To assess the efficacy of a transparent hood attached to the tip of a colonoscope for cecal intubation in TCS. DESIGN Prospective, randomized, controlled study. SETTING Single tertiary-referral center. INTERVENTIONS TCS. MAIN OUTCOME MEASUREMENTS Cecal intubation time and rate, complications, patient discomfort, and detection rate of colonic polyps. METHODS Patients who were to undergo screening and/or surveillance TCS for colorectal cancer were invited to participate in the study. Cecal intubation time and rate, complications, patient discomfort, and detection rate of colonic polyps were evaluated. RESULTS A total of 592 patients enrolled in this study were randomly allocated to the hood group and no-hood group. The mean (SD) cecal intubation time in the hood group and the no-hood group was 10.2 +/- 12.5 minutes and 13.4 +/- 15.8 minutes, respectively (P = .0241). The effect of its use was more prominent in the expert endoscopists group compared with those with moderate experience. The cecal intubation rate and the detection rate of small polyps in the 2 groups were similar. The grade of patient discomfort was significantly lower in the hood group. No complications were encountered with the use of the hood. CONCLUSIONS Use of a transparent hood on the tip of a colonoscope shortened the time required for cecal intubation and decreased patient discomfort; such use was more effective among experts in shortening the examination time.

Solid cystic tumor of the pancreas: report of six cases and a review of the Japanese literature

Although many cases of solid cystic tumor of the pancreas (SCT) have been reported, its nature and histogenesis remain controversial. We herein report six cases of SCT, including three cases of noncystic type. A review of 22 cases of noncystic type SCT, including our 3 cases, was carried out to compare their features with those of 173 cases of classic SCT reported in Japan. Noncystic type SCTs tend to occur in male patients and are smaller in size and less frequently symptomatic, although they show histological characteristics similar to those of classic SCTs. The developmental process might be a cause of cyst formation. The accumulation and analysis of many, at present, “atypical” cases for clarification of its nature, will, it is hoped, lead to a new nomenclature for this condition that adequately describes its biological origin.

Modes of spread in early ampullary cancer in terms of establishing proper indications for endoscopic papillectomy

Background:  Endoscopic papillectomy for adenomas of the ampulla of Vater has been reported and is gaining acceptance as an alternative to surgery in the treatment of early ampullary cancer. However, whether endoscopic treatment is justified as a treatment of choice for early ampullary cancer remains controversial. The aim of the present study was to elucidate the possibility of endoscopic papillectomy as a treatment of early ampullary cancer from the review of pathology of cases treated by surgical resection.

Temporary endosonography-guided biliary drainage for transgastrointestinal deployment of a self-expandable metallic stent

Endosonography-guided biliary drainage (ESBD) is now gaining acceptance as a useful alternative for the management of obstructive jaundice.1 At present, ESBD is used mainly to establish an anastomosis between the biliary tree and the duodenum, stomach, jejunum, or esophagus by placing a stent so as to bridge the bile duct and alimentary tract. We herein report a new application of ESBD, that is, its temporary use for gaining access to the bile duct in order to deploy a self-expandable metallic stent (SEMS) via the transhepatic route. In a patient with pylorus stenosis due to advanced gastric cancer with extrahepatic bile duct obstruction caused by nodal metastasis, a plastic stent was placed temporarily by ESBD to bridge the esophagus and the left hepatic duct. Ten days later, the stent was retrieved, leaving a guidewire in the bile duct, and a delivery unit of a SEMS was introduced into the bile duct over the guidewire via the sinus tract. The SEMS was then successfully deployed through the stenosis. No stent was left in the sinus tract. This procedure yields a mature fistula through which a delivery unit can be safely introduced into the bile duct followed by uneventful deployment of a SEMS.

Amylase levels in bile in patients with a morphologically normal pancreaticobiliary ductal arrangement.

BackgroundWe investigated the presence of occult pancreaticobiliary reflux in patients with a morphologically normal pancreaticobiliary ductal arrangement by measuring biliary amylase levels and compared histopathological findings of the gallbladder between groups with high and low biliary amylase levels.MethodsIn 178 patients with a normal pancreaticobiliary ductal arrangement who had undergone endoscopic retrograde cholangiopancreatography (ERCP), we sampled bile from the bile duct and measured amylase levels. Then we compared clinical features and histological findings of the gallbladder between high (HALG) and low amylase level groups (LALG).ResultsA high biliary amylase level was observed in 25.8% (46/178) of the patients. The prevalence of a high biliary amylase level was high in patients with gallbladder carcinoma (40%) and in those with choledocholithiasis (28.4%). The level of amylase in bile was high in patients with gallbladder carcinoma, adenomyomatosis of the gallbladder, and chronic cholecystitis. A strong correlation between the levels of amylase and lipase in bile and the dominance of amylase of pancreatic origin in bile were confirmed by isozyme analysis. Thickening of the gallbladder mucosa was a significant manifestation in HALG. Histological examination of the gallbladder mucosa showed that incidences of metaplastic change and atypical epithelium and Ki67-LI in were higher in HALG than in LALG.ConclusionsOccult pancreaticobiliary reflux is observed in a considerable number of ERCP candidates. Those who show an extremely high biliary amylase level, at least, may be at high risk for biliary malignancies.

Mediastinal emphysema after esophageal endoscopic submucosal dissection: its prevalence and clinical significance.

Aims:  To assess the prevalence and clinical significance of mediastinal emphysema (ME) after esophageal endoscopic submucosal dissection (ESD).

Snare-over-the-wire technique for safe exchange of a stent following endosonography-guided biliary drainage.

Endosonography‐guided biliary drainage (ESBD) is a new option that allows establishment of biliary drainage. Due to the diameter of the working channel of an echoendoscope, it is necessary to replace a small caliber stent with a larger one to lessen the risk of stent occlusion. However, insertion of a guidewire into the bile duct via the hole of the sinus tract following direct removal of a previously placed stent is not always possible, resulting in guidewire passage outside the fistula and bile leakage. Cannulation of the previously deployed stent, guidewire insertion into the bile duct via the cannula and the stent, and removal of the stent with the snare over the guidewire leaving the guidewire in place (the snare‐over‐the‐wire technique [SOW]) for stent exchange following ESBD was attempted. Four patients who required stent exchange following ESBD were included in the present study to evaluate the feasibility and usefulness of SOW. SOW was successful in all the cases. A new stent was also successfully deployed over the guidewire in all the cases. No complications were encountered. The snare‐over‐the‐wire technique is feasible and useful in stent exchange following ESBD for the reduction of the risk of guidewire migration.

Histological study of gallbladder and bile duct epithelia in patients with anomalous arrangement of the pancreaticobiliary ductal system: comparison between those with and without a dilated common bile duct

BackgroundWe histologically evaluated the epithelia of the gallbladder (GB) and bile duct (BD) in patients with anomalous arrangement of the pancreaticobiliary ductal system (AAPB), with regard to the shape of the common BD (CBD).MethodsThe GB and BD were studied histologically using surgical materials from 44 patients with AAPB: 27 with a dilated CBD (D-type) and 17 with a nondilated CBD (N-type).ResultsGB cancer and BD cancer were found in 11.1% and 3.7% of D-type and 17.6% and 0% of N-type respectively. Hyperplastic epithelium and atypical epithelium of the GB were frequently seen in both D-type (46%, 46%) and N-type (82%, 70%), while such epithelia of the BD were only seen in D-type (10%, 35%). The Ki67 labeling index of the nonneoplastic epithelium of the GB was high in both D-type (13.0%) and N-type (9.7%), though that of the BD was high in D-type (12.5%) but low in N-type (1.8%). The prevalences of pyloric gland metaplasia, intestinal metaplasia, and p53 protein overexpression of the nonneoplastic epithelium did not show any significant differences between D-type and N-type.ConclusionsIt is suggested that the BD epithelium of N-type probably has a lower potential for developing malignancy than that of D-type, while the GB epithelia of both D-type and N-type have a high potential for developing malignancy. This might support the selection of simple cholecystectomy as the treatment of choice in AAPB patients of N-type, although further investigation of the BD epithelium is required in a larger number of such patients.

Efficacy of acetic acid-spraying method in diagnosing extension of barrett's cancer under the squamous epithelium

Aim:  Endoscopic diagnosis of the lateral extension of Barretts cancer under the squamous epithelium (BCUS) is sometimes difficult because the cancer is unobservable in the esophageal lumen. The aim of the present study was to clarify the endoscopic features of the extension of BCUS and verify the usefulness of the acetic acid‐spraying method (AAS) for diagnosis.

INTRADUCTAL ULTRASONOGRAPHY BEFORE BILIARY DRAINAGE AND TRANSPAPILLARY BIOPSY IN ASSESSMENT OF THE LONGITUDINAL EXTENT OF BILE DUCT CANCER

Aim:  We evaluated the diagnostic efficacy of transpapillary intraductal ultrasonography before biliary drainage (IDUS‐BD) and transpapillary biopsy (TPB) for the assessment of the longitudinal extent of bile duct cancer.