Using volume index and lateral hepatic angle to differentiate biliary atresia from TPN-associated cholestasis.

Objectives: Differential diagnosis between biliary atresia (BA) and total parenteral nutrition-associated cholestasis (TPN-AC) and early treatment for cholestatic infants are challenges for evaluating neonatal or infantile cholestasis. The aim of our retrospective study was to apply noninvasive indices of magnetic resonance images to differentiate BA from TPN-AC.

Methods: A total of 44 patients diagnosed as having BA (n = 30) or TPN-AC (n = 14) were included in the present retrospective study and underwent abdominal magnetic resonance imaging to evaluate the possibility of BA. The left lateral hepatic angle was determined from the coronal image of the left portal vein and portal vein of segment II. Adjusted volume indices of the right hepatic lobe (AVIR) and left lateral segment (AVILL) were calculated as the product of 3 diameters (centimeters) divided by each patient's body weight.

Results: The left lateral hepatic angles of patients with BA (74° ± 21°) were significantly larger than for patients with TPN-AC (33° ± 9°) and controls (36° ± 5°, P < 0.05). AVILL of the BA (0.037 ± 0.012 cm/g) and TPN-AC groups (0.042 ± 0.030 cm/g) were not significantly different (P = 0.61) but were significantly larger than for controls (0.020 ± 0.011 cm/g) (P < 0.05). The right hepatic lobe to left lateral hepatic segment ratio (RLR) of patients with BA was significantly (P < 0.05) smaller (1.61 ± 0.58) than for patients with TPN-AC (3.08 ± 2.43) and controls (2.98 ± 0.92). Patients with BA could have relative sparing and selective enlargement of the left lateral liver with a resultant lobar difference and blunt left lateral hepatic angle.

Conclusions: Noninvasive indices of lobar difference and left lateral hepatic angle help differentiate patients with BA from those with TPN-AC.