Ultrasonography of Choledochal Cysts in Children

Imaging diagnosis of a giant choledochal cyst in an infant

The usual etiologies of giant abdominal cystic masses in infants are mesenteric cyst, enteric duplication cyst, ovarian cyst in females, cystic lymphangioma, however, the presentation of a choledochal cyst in a gigantic form, is unusual. The primary modality for diagnosis of this entity is ultrasound, followed by MRI. The characteristic ultrasound features of a choledochal cyst are a well-defined cystic lesion which may be found to replace any segment of the biliary tree and is distinctly separate from the gallbladder. The associated anomalies are biliary atresia, gallbladder atresia, hepatic fibrosis and those of the pancreatico-biliary ductal system. MRI with MRCP has a conclusive role in confirming the ultrasound diagnosis. Choledochal cysts are currently classified as proposed by Todani et al, into five types. Herein, we report the case study of a 4-month-old male infant afflicted with a gigantic, Type1 Choledochal cyst, complicated by perforation, which was diagnosed by us at the first instance itself, using ultrasound examination and confirmed by MRI. The diagnosis was further confirmed at surgery and histopathology. The recommended treatment of cyst resection accompanied by a hepatico-jejunostomy bypass procedure, was successfully performed in the reported infant.

Common bile duct dilatations in asymptomatic neonates: incidence and prognosis

Background. This retrospective study reviewed 213 asymptomatic neonates with common bile duct (CBD) dilatations diagnosed via ultrasound to evaluate their incidence and outcomes. Materials and Methods. From August 2001 to July 2010, 18,230 abdominal ultrasound scans were performed as newborn screening. There were 213 (1.17%) cases of CBD dilatation. Dilatation of neonatal CBD was defined when its diameter was ≥2 mm. The neonates' birth history, CBD size, and follow-up results were analyzed. Results. In the 213 infants, four cystic dilatations (1.88%, 4/213) that were eventually diagnosed as choledochal cysts (CC). Among 209 neonates with fusiform dilatations (size 2.0–6.7 mm), 77 had ultrasound follow-up and 87% of them resolved spontaneously which were diagnosed as transient CBD dilatation (TCBDD). Eighty percent of TCBDDs resolved within 6 months. Patients with initial CBD size ≥3 mm had significantly lower resolution rate and neonates whose mothers are older than 35 years took longer time to resolve. Conclusion. The incidence of CBD dilatation in asymptomatic neonates was 1.17%. Eighty percent of TCBDDs resolved within 6 months. Regular ultrasound follow-up every 6 months may be appropriate for asymptomatic neonates with fusiform CBD dilatations to ensure resolution or progression.