Takao Wakabayashi

Clinical features of eosinophilic esophagitis: Ten Japanese cases

Aim:  We studied eosinophilic esophagitis (EE) to clarify the clinical and endoscopic features of a Japanese case series.

Involvement of NAD(P)H:Quinone Oxidoreductase 1 and Superoxide Dismutase Polymorphisms in Ulcerative Colitis

Inflammatory bowel disease is a multifactorial disease. Oxidative stress has been thought to be one of etiologic factor for inflammatory bowel disease. The genes superoxide dismutase (SOD2) and NAD(P)H:quinone oxidoreductase 1 (NQO1) are involved in inflammation and oxidative stress. The purpose of the present case-control study with 134 patients with ulcerative colitis (UC) and 125 healthy controls was to determine whether polymorphisms of these genes, the NQO1 C609T and the SOD2 Ala-9Val, are associated with the risk of UC and influence the clinical characteristics. These polymorphisms were examined by polymerase chain reaction-restriction fragment length polymorphisms and direct sequencing. In patients showing steroid resistance, the number with the NQO1 T/T genotype was significantly higher than other genotypes (odds ratio 9.45, 95% confidence interval 2.46-41.6, p = 0.002). In the patients whose onset of UC was age 20 years or younger, more patients had SOD2 T/T genotype than the other genotypes (odds ratio 6.46, 95% confidence interval 0.82-51.0). No association between these polymorphisms and UC risk was apparent. The NQO1 C609T polymorphism may influence steroid resistance of UC patients, while the SOD2 Ala-9Val polymorphism may influence age of onset of UC. Oxidative stress may influence the clinical features of UC.

The Diagnosis of the Anomalous Connection of Pancreaticobiliary Ducts Without Biliary Dilatation—The Usefulness of US/EUS Serial Examination—

The anomalous connection of the pancreaticobiliary duct (ACPBD) without accompanying dilatation of the bile duct (non‐dilated type of ACPBD) has recently been found to be associated with gallbladder cancer at a rather high rate. We analyzed the diagnostic process of 5 patients with non‐dilated type of ACPBD including 3 asymptomatic cases and reviewed the literature. Symptoms and laboratory data were not useful in detecting this type of lesion. All our patients were checked by ultrasonography for gallbladder lesions which are suggested by: wall thickening, multiple polyps, intramural gall stones, cholecystolithiaisis, and debris. ACT revealed only wall thickening of the gallbladder. An EUS revealed a high rate of ACPBD in addition to the ultrasonographic findings of gallbladder lesions obtained by US. An ERCP was effective in clearly demonstrating ACPBD, but was not so useful for the diagnosis of concomitant gallbladder lesions. Therefore, an US is considered to be a useful means for screening this disease, and EUS is useful as a procedure to follow in order to select patients with or without ACPBD, because EUS can be conducted on an outpatient basis and is highly sensitive in detecting ductal anomalies in ACPBD. Therefore, the US/EUS serial examination is thought to be an effective means for diagnosing this disease.

Clinical study using novel endoscopic system for measuring size of gastrointestinal lesion

AIM To verify the performance of a lesion size measurement system through a clinical study. METHODS Our proposed system, which consists of a conventional endoscope, an optical device, an optical probe, and a personal computer, generates a grid scale to measure the lesion size from an endoscopic image. The width of the grid scale is constantly adjusted according to the distance between the tip of the endoscope and lesion because the lesion size on an endoscopic image changes according to the distance. The shape of the grid scale was corrected to match the distortion of the endoscopic image. The distance was calculated using the amount of laser light reflected from the lesion through an optical probe inserted into the instrument channel of the endoscope. The endoscopist can thus measure the lesion size without contact by comparing the lesion with the size of the grid scale on the endoscopic image. (1) A basic test was performed to verify the relationship between the measurement error eM and the tilt angle of the endoscope; and (2) The sizes of three colon polyps were measured using our system during endoscopy. These sizes were immediately measured by scale after their removal. RESULTS There was no error at α = 0°. In addition, the values of eM (mean ± SD) were 0.24 ± 0.11 mm (α = 10°), 0.90 ± 0.58 mm (α = 20°) and 2.31 ± 1.41 mm (α = 30°). According to these results, our system has been confirmed to measure accurately when the tilt angle is less than 20°. The measurement error was approximately 1 mm in the clinical study. Therefore, it was concluded that our proposed measurement system was also effective in clinical examinations. CONCLUSION By combining simple optical equipment with a conventional endoscope, a quick and accurate system for measuring lesion size was established.

SPECIFIC DIAGNOSIS OF BILIARY STRICTURES BY QUANTITATIVE ASSESSMENT USING A CHOLANGIOSCOPICALLY DERIVED HEMOGLOBIN INDEX

Background:  We used percutaneous transhepatic cholangioscopy for detailed assessment of biliary tumors. Among the most important endoscopic findings is greater mucosal vascularity in malignant than in benign biliary strictures. Development of digital image processing now permits measurement of mucosal hemoglobin volume as a hemoglobin index. We studied the clinical usefulness of this hemoglobin index for differentiating malignant from benign biliary strictures.

Assessment of Underlying Blood Vessels in Gastric Ulcers with Bleeding Episode by Endoscopic Color Doppler Ultrasonography

We used endoscopic color Doppler ultrasonography to detect hemorrhagic gastric ulcer, and to determine whether this modality could show blood vessels present deep to ulcers and whether these vessels influenced clinical course. Subjects were 20 patients with hemorrhagic gastric ulcers which had visible vessels on the ulcer base endoscopically. In 11 of 20 patients (group P) color signals indicating blood flow were observed, in which a weak pulsatile wave was detected in five cases. In two operated cases the signals were confirmed as blood vessels histologically. The diameters of these vessels were over 0.35 mm. It was thought that in cases undetectable on endoscopic color Doppler ultrasonography (group N) the diameter of vessels was too narrow or the velocity of blood too slow. There were no differences in the clinical background of group P and group N. However, ulcer bleeding was more severe in group P cases (P<0.05). Many patients in whom blood flow was detected experienced repeated ulcer bleeding as well as ulcer recurrences. Patients with hemorrhagic ulcers and in whom ultrasonic imaging demonstrates blood flow should be managed with great care. (Dig Endosc 1999; 11: 231–235)

Application of peroral cholecystoscopy in a case of cholecystocolic fistula

A patient with a cholecystocolic fistula, complicating cholecysto‐choledocholithiasis, was treated endoscopically with gallbladder observation by peroral cholecystoscopy (POCCS). The patient was a 71‐year‐old female admitted to our hospital for investigation and treatment of biliary stones and a cholecystocolic fistula. Endoscopic lithotripsy and extracorporeal shock wave lithotripsy (ESWL) were performed after endoscopic sphincterotomy, and the gallbladder was subsequently investigated using a duodenoscope/ cholangioscope of the mother and baby type. Full distension of the gallbladder with saline solution allowed POCCS observation of the entire surface. The gallbladder mucosa was smooth, and neither stones nor tumors were observed. Though the cholecystocolic fistula itself could not be observed, we concluded that it had resulted from cholecystitis. Peroral cholecystoscopy is thus a useful method of investigating the gallbladder in such cases.