Early US findings of biliary atresia in infants younger than 30 days.

PURPOSE

To investigate and compare ultrasound (US) findings for the diagnosis of biliary atresia (BA) in infants younger than 30 days with those of infants older than 30 days.

MATERIALS AND METHODS

From 2000 to 2015, we reviewed hepatobiliary US images in 12 BA infants younger than 30 days (younger BA group) and 62 BA infants older than 30 days (older BA group) before Kasai procedure. Eight (67%) of younger BA group underwent follow-up US examinations before Kasai procedure. Our review of the images focused on triangular cord sign, gallbladder (GB) abnormalities, vascular changes, and signs of portal hypertension.

RESULTS

The triangular cord sign was present in 17% of younger BA group and in 56% of older BA group (P=.024). GB abnormalities were commonly identified in both groups. The hepatic artery diameter was significantly smaller in younger BA group than in older BA group (P<.001). Signs of portal hypertension were less common in younger BA group (17%) than in older BA group (84%) (P<.001). Follow-up US of two infants in younger BA group showed a new appearance of the triangular cord sign.

CONCLUSION

BA infants younger than 30 days showed atypical US findings compared with those older than 30 days.

KEY POINTS

• BA infants younger than 30 days show atypical US findings. • GB abnormalities were common in both younger and older BA group. • Subsequent US examination may be helpful to diagnose BA in young infants.