Macro-regenerative nodules in biliary atresia: CT/MRI findings and their pathological relations

Table 1 Summary of CT and MRI characteristics

	Case 1	Case 2	Case 3	Case 4	Case 5	Case 6	Case 7
Size (cm)	9; 5; 1.61	4.5	2.1	3.5	7	7.5	13
Location (segment)	S5-8/S2	S6	S8	S5	S4-5-8	S4-5-8	S5-6-7-8
Density in CT (-) relative to liver parenchyma	Hyperdense; Hyperdense	Hyperdense	Isodense	Isodense	Hyperdense	Hyperdense	Hyperdense
Enhancement in CT	No	Early enhancement and early wash-out	Delayed portovenous enhancement	No	Arterial and portovenous enhancement	No	Early patchy enhancement early wash-out
MRI T1WI/T2WI/C+	Hyperintense/Hypoinstense	Hyperintense/Hypoinstense	Hypoinstense/Hyperintense	Hypoinstense/Hyperintense	Not done	Hyperintense/Hypoinstense	Isointense/Hypoinstense
Septa T1WI/T2WI/C+	Not discernible	Hypoinstense/Hypointense/Enhanced	Not discernible	Not discernible	Not done	Hypoinstense/Hypointense/Enhanced	Not discernible
Presence of internal tubular structure (portal tract)	Yes; yes	No	No	No	Yes	Yes	Yes
Calcifications	No	No	No	Yes	No	No	No

¹This small nodule is not detected by either CT or MRI.