Pathology and pathophysiology of gastric mucosal injuries were studied from the endoscopic point of view, and the following our results were presented. 1.Thermal injuries in canine gastric mucosa were studied. Marked atrophic gastritiswith pseudopyloric gland heterotopia was experimentally produced in dogs with theconsecutive administration by gastric intubation of 300ml of 58°C warm water for 175 to 457days. The results suggest that the thermal agent is one of the cause of atrophicgastritis. 2.The gastric ulcerogenesity of cinchophen(220mg/kg/5 × W)was evaluated in theferret. It was most severe at 3-4 days. Secretory studies revealed no change in acidconcentration and pepsin activity. Histopathologic study of 6 antral pouch ferrets demon-strated only mild acute inflammatory changes following cinchophen administration directly into the pouch and no antral changes following peroral administration. The results showgastric acid play an imoirtant role in cinchophen-induced ulcerogenesis. 3.To study the role of mucus bicarbonate barrier(MBB)in gastric mucosal cytoprotection, experimental chamber system was newly deviced. The thickness of mucus gellayers, grade of back diffusion of gastric acid, and potential difference were measured inthe rat gastric mucosa. Gastric mucus was secreted reactively to the various stimulantsincluding aspirin, ethanol(100%), 25%Nacl solution and PGE₂ to maintain the MBBfunction. When stimulations were too strong, back diffusion of gastric acid occurred, followed by decrease in secrtion of gastric mucus as well as alkali, and, finally, resulted ingastric mucosal injuries. 4.The role of bile acid regurgitation was clinically studied with reference to thecarcinogenesis of remnant gastric mucosa. Mucosal biopsies were taken from the marginof the stomas of gastric pouch, and evaluated their histological atypicity based on thecriteria of Japanese Society of Gastric Cancer. The incidence of group III was significantlyhigh in specimens collected from stomal margins of Billroth-II anastomoses elapsed morethan 10 years compared to those from Billroth-I anastomoses(P<0.01), suggesting therelationship between bile acid regurgitation and carcinogenesis. In addition, cumulativehazard rate to mucosal atypicity was high in helicobacter pylori(HP)positive gastricmucosa, suggesting the contribution of HP in carcinogenesis of remnant stomach. 5.Role of nitric oxide(NO)on adaptive cytoprotection was studied with similarchamber system deviced for monitoring NO genertation, gastric mucosal blood flow(laser doppler probe)and gastric electromyogram. From our study, it was thought to be animportant factor that back diffusion of gastric acid into the mucosa induce the NOgeneration in the gastric mucosa, followed by the transient increase in the gastric mucosalblood flow, indicating the NO generation play an important role to maintain the gastric mucosal blood flow.

View full abstract

The aim of the present study was to investigate the inactivating effect of acidelectrized water(AEW)and peracetic acid(PAA)on the human immunodeficiency virus(HIV). The methods were as follows.1)The inactivation test used HIV solutions that wereprepared by adding HIV to AEW or PAA. Saline was used as the control.2)For thecytotoxicity test, a culture medium was added to AEW or saline instead of HIV. SUPT-1cells was inoculated with the test or control HIV solution and incubated after theinoculum was adjusted to contain 5 x 104 cells/ml. The inactivating effects were studiedusing WST-1 assay as an indicator of intracellular dehydrogenase activity and indirectfluorescent antibody staining to examine HIV antigen expression in the host cell. Cytotox-icity was investigated by comparing dehydrogenase activity in the AEW-or PAA-treatedcells with that in the control cells. Whereas host cells inoculated with saline-treated HIVshowed proliferation on day 4 and reduction in enzyme activity due to HIV proliferationon day 7, HIV, proliferation was observed on both days 4 and 7 for the host cells inoculatedwith AEW-treated HIV. For the host cells inoculated with PAA-treated HIV, enzymeactivity was very low on day 4 and cell proliferation was observed on day 7. No virusantigen-positive cells were detected on indirect fluorescent antibody staining of the cellsinoculated with AEW-or PAA-treated HIV. The cytotoxicity test showed satisfactoryproliferation of the host cells in contact with saline or AEW, but no proliferation of thecells in contact with PAA was evident by day 4, with proliferating cells first appearing onday 7. The results indicate that AEW has the capacity to rapidly inactivate HIV and thatPAA also has an inhibitory effect on HIV, although it also exhibits a cytotoxicic effect.Both AEW and PAA produced an HIV inactivating effect in 30 seconds. The resultspresented would justify the conclusion that AEW and PAA are useful for cleaning anddisinfecting endoscopes and other medical instruments.

View full abstract

We investigated the usefulness of the endoscopic resection of the tumor of the papilla. Thirty patients have been diagnosed to have the tumor of the papilla on endoscopic examination with a side-viewing videoendoscopy. The endoscopic findings were classified as three types (I: tumor type, II: granular type, III: normal-like type). All the 30 adenomas of the papilla diagnosed as adenoma by the biopsy under direct vision on endoscopy and limited to the mucosal layer by imaging modalities. Excision was performed in a radical fashion using pure cutting current. The resected specimen was submitted to histologic analysis by serial sectioning. We compared biopsy specimens with the resected tumor to compare to the pathological diagnosis. We examined the pathological diagnosis and the complications of this endoscopic procedure. The final pathological diagnosis by the resected specimens were cancer in 2 of 30 cases and adenomain the remaining cases. As for the tumor in the margin of the resected specimens, tumor is free in 15 of 30 cases (50%). After treatment, the pathological diagnosis of the biopsy from the edge of the ulcer after the resection is free of the residual tumor in 10 of 15 cases (67%) and positive in the remaining 5 cases (33%). In the 5 cases, we treated the residual tumor by hot biopsy. On the resection of the tumor, perforation of the duodenal wall was not seen. Duodenal bleeding was seen in one case after the resection. A cute pancreatitis was seen in 1 out of 30 cases (3%). Serum Hemoglobin fell beyond 3g/dl in 7 cases. Obstructive jaundice beyond 3mg/dl in total bilirubin was seen in 3 among 30 cases (10%). These complications recovered by conservative therapy. In conclusion the endoscopic resection of the adenoma of the papilla of Vater was a safe treatment and useful in the final pathological diagnosis of the adenoma diagnosed by biopsy.

View full abstract

Thirty five patients with colorectal mucosal cancer resected surgically from 1993 to 1997 were studied to evaluate the problems of endoscopic resection and benefits of surgical resection. There were 13 patients with large tumor. In most of the patients, the dimension of tumor was larger than 2/3 of large bowel. This "relative tumor size was important for endoscopic resection. There were 6 patients with tumor for which endoscopic resection could not be performed. Of the 6 patients, 2 had a positive non-lifting sign, 2 having a depressive lesion (IIc') that could not be snared, and 2 having a cecal tumor on the appendical orifice. Eight patients with tumor in the rectum (Rb) were selected to have surgical local excision for certainly negative tumor margin. Eight patients were over-diagnosed to have SM' massive invasive cancer by endoscopic finding. In general, endo-scopic resection should be performed for colorectal mucosal cancers but the fact that there were patients with tumor which could not be resected endoscopically and surgical resection had advantage in some cases over endoscopic resection leads to the necessity to select the appoprinte method of resection.

View full abstract

In cases with sphincter Oddi dysfunction, we occasionally find a filling defect at the bile duct terminal. It is considered to be the papillary folds protruding into the bile duct, with peristalsis of the sphincter Oddi. In these cases, it is very important to differentiate elevated lesions in the bile duct terminal. Many methods have been tried to evaluate the papillary movement, but they are often difficult and bothersome. We performed intraductal ultrasonography (IDUS) without antiperistaltic drugs to assess the papillary movement in 6 cases. IDUS could visualize the movement of sphincter Oddi very well. This method is easy to perform, non-invasive and very useful for the differential diagnosis of elevated lesions in the bile duct.

View full abstract

To clarify the minimum detectable size of small polypoid lesions of biliary duct using intraductal ultrasonography (IDUS), we scanned 28 neoplastic and nonneoplastic small polypoid lesions and also silk threads. We detected 25 lesions 0.5 mm or more in size by IDUS while only one of the 25 lesions was detected by direct cholangiography. However we could not detect lesions which were less than 0.5 mm or growed thick. In the study on silk thread, we detected 0.5 mm or more in size and distinguished a distance of 0.5 mm between two silk thread. In conclusion, IDUS is very useful modality to detect small polypoid lesions of the biliary duct in comparison with other modality.

View full abstract

A 59-year-old woman was admitted to our hospital in April 1993 because of dysphagia for a year. She had undergone proximal gastrectomy in 1980. Esophagogram and endoscopic examination showed an annular stricture (5mm in diameter) of the upper thoracic esophagus at a distance of 25cm from the dental arch. Histologic examination of biopsy specimens, 24 hour pH monitoring and chemical findings of the reflux juice in the esophagus demonstrated benign esophageal stricture with Barrett's esophagus caused by ref lux esophagitis. Endoscopic balloon dilatation was performed. We reported this case because of a rare case of severe stricture of the upper thoracic esophagus after proximal gastrectomy.

View full abstract

Mucosal bridge of the esophagus is a rare disease. We herein describe a case of reflux esophagitis with mucosal bridge formation. A 73-year-old female was admitted to the Kusama hospital with heart burn in November, 1997. The patient had been treated by HZ receptor antagonist for ref lux esophagitis for one year. Esophagoscopy showed several linear membranous disorders from the upper esophagus, and a mucosal bridge formation in the middle portion of the esophagus which separated completely the esophageal cavity. Based on these findings, she was diagnosed as esophageal mucosal bridge due to reflux esophagitis. After treatment using proton pump inhibitor for two weeks, mucosal bridge was markedly improved and almost normal esophageal mucosa covered the lesion with slightly scarring.

View full abstract

A 44-year-old male was admitted to Iwase Public Hospital because of anemia due to tarry stool on July 18th, 1997. Emergent endoscopy revealed an exposed bleeding vessel in the ulcerous lesion on the posterior wall of the upper body of the stomach. The bleeding was succesfully stopped by an endoscopic hemoclipping. Endoscopic reexamination performed two weeks after the hemostasis revealed the ulcerative lesion simulating type IIc early gastric cancer. Histological examination of the biopsied speciemens obtained from the lesion showed a signet ring cell carcinoma. Histology of the resected stomach showed a mixture of signet ring cell carcinoma and poorly differentiated adenocarcinoma partially invading the submucosal layer. Enlarged muscular vessels were also shown in the submucosal layer. We diagnosed this case as a type IIc early gastric cancer simulating Dieulafoy's ulcer on the endoscopical and pathological findings.

View full abstract

A 46-year-old woman was detected an absence of haustra on the right side of the colon and a large filling defect in the cecum by barium enema study at local hospital and referred to our hospital for further evaluation. Colonoscopy revealed diffuse mucosal redness and several aphthous ulcers between the splenic flexure and the cecum, and these findings were suspected of ulcerative colitis. Biopsy of the right colon confirmed a diagnosis of ulcera-tive colitis. The colonoscopy also showed a pedunculated polyp, about 4cm in diameter, in the cecum and endoscopic snare polypectomy was performed. Microscopically, the polyp consisted of fibroblastic and vascular proliferation with inflammatory cell infiltration, predominantly eosinophils. A histopathological diagnosis of inflammatory fibroid polyp was made. Inflammatory fibroid polyp of the colon is rare and to our knowledge it has not been found previously in combination with ulcerative colitis.

View full abstract

A 50-year-old woman was underwent a endoscopic mucosal resection (EMR) for a submucosal tumor, 8 mm in size, on transverse colon followed by the suture with clipping. Twenty-two hours after EMR she complained epigastralgia and fever. Abdominal CT examination revealed free air arround the transverse colon and duodenum suggesting the perforative peritonitis. Because muscle defence and resistance of upper abdomen were not found, conservative treatment with fasting and antibiotics was selected. It resulted in the improvement of inflammatory findings and disappearance of free air 1 week later. Histological findings of resected tumor revealed a carcinoid accompanied with the superficial layer of proper muscle. This case suggested that we should carefully bear in mind to resect a submucosal tumor by endoscopic procedure whenever done with the clipping method.

View full abstract

The transjuguiar retorograae oonteratlon (TJO) is an ettective method for the treat-ment of gastric varices with gastrorenal shunt, However, the effect of TJO for gastric varices has not been shown in cases with no gastrorenal shunt and in cases after left nephrectomy. We experienced a successful case of TJO for isolated gastric varices after left nephrectomy and this is the first case in the world literature as for as we know. A 69 -year-old female, who had a history of left nephrectomy, was admitted to our hospital with a complaint of tarry stool. An endoscopic examination revealed oozing isolated gastric varices. Splenic angiography showed a narrow gastrorenal shunt which converged to the root of the ligated left renal vein. Treatment was succeeded in using TJO technique with 5 Fr. occlusive balloon catheter.

View full abstract

A 55-year-old male was admitted to our hospital in July, 1997, because of epigastric pain and fever. Two depressive lesions were found on upper GI endoscopic examination and black substance like gallstone was watched through the lesion. The CT showed a high density shadow in the position of the common bile duct (CBD) and the duodenum on the CBD, therefore, the fistula of the duodenum and CBD was suspected. ERCP and upper GI X-ray examination showed the fistula itself, the two choledochoduodenal fistulas were diagnosed definitely. The operation was performed on August 5, 1997. The bulb adherent to the gallbladder and CBD was dessected from them and the oral fistula was resected. From the resected space, the stone was removed, 40×23%times;21mm in size, and T-tube was inserted to CBD via that space. The post operative course was uneventful and he was discharged on the 41st postoperative day.

View full abstract