-Case Reports-

Usefulness of Thin-Slice Contrast-Enhanced Computed Tomography in Detecting Perforation Site in Congenital Biliary Dilatation: A Case Report

Yuka Kasai¹, Ryoji Aoki¹, Nobuhiko Nagano¹, Hide Kaneda², Tsugumichi Koshinaga² and Ichiro Morioka¹

¹Department of Pediatrics and Child Health, Nihon University School of Medicine, Tokyo, Japan
²Department of Pediatric Surgery, Nihon University School of Medicine, Tokyo, Japan

The site of perforation is difficult to identify preoperatively in many cases with spontaneous perforation of congenital biliary dilatation (CBD). We report a case of spontaneous perforation of CBD in which the perforation site was identified preoperatively using thin-slice contrast-enhanced computed tomography (CT). The patient was a girl aged 1 year and 4 months. She was admitted to our hospital because of vomiting and diarrhea that had continued for 3 days prior to admission. Abdominal contrast CT on admission showed dilated common bile duct, thickening of the gall bladder wall, and marked ascites. In addition, an area of low density with a diameter of 1 cm was detected near the neck of the gallbladder. We evaluated the area via thin-slice contrast-enhanced CT and detected a defect in the wall of the bile duct. Cholangiography revealed abnormal confluence of the pancreaticobiliary duct and a protein plug in the common duct. A diagnosis of CBD with perforation of the bile duct was made, and surgery was performed. The intraoperative findings matched that seen on the enhanced CT. There are some reports of pseudocysts and fluid retention around the perforation site; however, no reports are found in which the perforation site was confirmed by preoperative CT. If localized fluid retention is observed in cases with biliary perforation, confirmation with thin-slice contrast-enhanced CT might be useful for identifying the perforation site.

J Nippon Med Sch 2022; 89: 623-628

Keywords
congenital biliary dilatation, fluid accumulation, perforation site, spontaneous perforation, thin-slice contrast-enhanced computed tomography

Correspondence to
Ryoji Aoki, MD, PhD, Department of Pediatrics and Child Health, Nihon University School of Medicine, 30-1 Oyaguchikamicho, Itabashi-ku, Tokyo 173-8610, Japan
aoki.ryoji@nihon-u.ac.jp

Received, June 5, 2021
Accepted, September 15, 2021