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Atsuo Nakamura

Publications and source records attributed to Atsuo Nakamura.

5 recordsLinked to original sources
PubMed2003

Prophylactic clip application does not decrease delayed bleeding after colonoscopic polypectomy.

BACKGROUND: The most common major complication of colonoscopic polypectomy is postpolypectomy hemorrhage. Although several factors have been implicated in the occurrence of hemorrhage, accurate prediction of delayed bleeding remains difficult. This randomized controlled trial evaluated the efficacy of prophylactic clip application for prevention of delayed postpolypectomy bleeding. METHODS: Postpolypectomy ulcers created by colonoscopic removal of polyps (mean size 7.8 [4.0] mm) with the endoscopic mucosal resection technique were randomly assigned to prophylactic clip placement (n = 205) or no clip (n = 208). Baseline characteristics of the patients and polyps excised were comparable between the groups. Delayed bleeding was defined as the postprocedure passage of bloody stool or massive hematochezia. The site of delayed bleeding was identified at emergent colonoscopy. RESULTS: Delayed bleeding was identified from 2 ulcers in each group from 1 to 4 days after resection (mean 2.3 days). Delayed bleeding occurred from 0.98% of ulcers in the clip group and 0.96% in the non-clip group (p > 0.9999). No patient with delayed bleeding required transfusion or surgery. CONCLUSIONS: Prophylactic clip placement did not decrease the occurrence of delayed bleeding after colonoscopic polypectomy.

Adenocarcinoma↗
PubMed2003

Accuracy of magnifying endoscopy with methylene blue in the diagnosis of specialized intestinal metaplasia and short-segment Barrett's esophagus in Japanese patients without Helicobacter pylori infection.

BACKGROUND: The use of methylene blue chromoendoscopy in the diagnosis of specialized intestinal metaplasia in short-segment Barrett's esophagus is controversial. This study evaluated the use of magnifying endoscopy with methylene blue for this purpose. METHODS: A total of 30 patients (21 men, 9 women; median age 61 years, range 32-79 years) with short lengths of columnar-lined esophagus were enrolled in a prospective trial of magnifying endoscopy with methylene blue in which the appearance after methylene blue staining was used to target biopsy specimens. Patients were screened for Helicobacter pylori infection, and only those without infection were enrolled (because many Japanese patients have pan-gastritis caused by H pylori infection, and intestinal metaplasia distal to the squamocolumnar junction may be secondary to H pylori-induced gastritis). All biopsy specimens were stained with H and E; MUC2 immunostaining was used to identify specialized intestinal metaplasia. RESULTS: Thirty patients with short-segment columnar-lined esophagus underwent magnifying endoscopy with methylene blue. Ninety-three biopsy specimens were obtained, 33 from methylene blue-stained areas and 60 from unstained areas, each about 7 mm from the marginal edge of stained areas. Specialized intestinal metaplasia was confirmed in biopsy specimens from 28 of the 33 stained areas (sensitivity 84.8%); in biopsy specimens from 55 of the 60 unstained areas, specialized intestinal metaplasia was not found (specificity 91.7%). In magnified views of methylene blue-positive areas, a tubular, cavernous, or elliptical pattern was seen. Sixteen of 21 men (76.2%) and 3 of 9 women had specialized intestinal metaplasia, and short-segment Barrett's esophagus was diagnosed in these patients. Even in patients with less than 1 cm of columnar-lined esophagus, 8 of 10 stained areas contained specialized intestinal metaplasia (sensitivity 80%) and 23 of 24 unstained areas did not (specificity 95.8%). Six of 12 patients (50%) with less than 1 cm of columnar-lined esophagus had specialized intestinal metaplasia. In total, 19 of 30 patients had specialized intestinal metaplasia. CONCLUSIONS: Magnifying endoscopy with methylene blue selectively detects specialized intestinal metaplasia within short-segment columnar-lined esophagus.

Adult↗
PubMed2002

Characteristic endoscopic and magnified endoscopic findings in the normal stomach without Helicobacter pylori infection.

BACKGROUND AND AIMS: The aim of this study was to clarify the endoscopic features of the Helicobacter pylori (H. pylori)-free stomach by examining the arrangement of minute points visible on the corpus. Since these points were clarified by magnifying endoscopy as collecting venules, this finding was termed 'regular arrangement of collecting venules (RAC)'. The findings from more endoscopic studies are presented and the differences between magnified views of the normal and H. pylori-infected corpus and antrum are described in particular. METHODS: The study group consisted of 557 patients who were subjected to endoscopy and checked for H. pylori. The RAC in each patient was assessed. Magnifying endoscopy in 301 patients was used to examine the corpus and in 94 patients to examine the antrum. RESULTS: One hundred and fifty-eight patients had normal stomachs without H. pylori. We diagnosed 389 patients with H. pylori gastritis. In 10 patients H. pylori was not detected, but inflammation was present. Of the 158 patients with H. pylori-negative normal stomachs, 151 had RAC. As a determinant of the normal stomach without H. pylori infection, the presence of RAC had 93.8% sensitivity and 96.2% specificity. All 30 patients with H. pylori-negative normal stomachs had a well-defined ridge pattern (wDRP) on the antrum as observed under magnifying endoscopy. As a determinant of the normal stomach without H. pylori infection, wDRP had a specificity of 100%, but a sensitivity of only 54.5%. CONCLUSIONS: The presence of RAC is characteristic of a normal stomach without H. pylori. Magnified views of the normal antrum were different from that of the normal corpus.

Adolescent↗
PubMed2002

An early cancer of the gastric cardia arising from carditis after long-term gastroesophageal reflux disease in the absence of Helicobacter pylori infection.

We describe an early gastric cardiac cancer in a patient who had suffered long-term gastroesophageal reflux disease (GERD) but showed no evidence of infection with Helicobacter pylori. Proximal gastrectomy and partial resection of the lower esophagus was performed. Histological examination revealed the lesion to be a gastric cardiac adenocarcinoma, which had partially invaded the submucosal layer. Intestinal metaplasia was also found in some areas. Inflammation, however, appeared to be limited to the gastric cardia. This cancer may have arisen via a sequence of carditis and cardiac intestinal metaplasia, due primarily to the GERD and not to H. pylori infection.

Adenocarcinoma↗