Peri-aortofemoral prosthesis urinoma: diagnosis by Tc-99m MAG3 SPECT/CT and differentiation from simultaneous hepatobiliary excretion.

A 75-year-old woman developed renal failure 1 week after elective aortobifemoral bypass surgery. Postoperative computed tomography showed right hydronephrosis. Tc-99m mercaptoacetyltriglycerine (MAG3) scintigraphy was performed to exclude renal obstruction or acute tubular necrosis. Planar MAG3 images demonstrated right hydronephrosis and unusual accumulation of tracer between the kidneys and the right upper quadrant of abdomen, with new areas of activity in the right lower quadrant on delayed images. SPECT/CT demonstrated MAG3 activity within fluid collections adjacent to the aorta and right iliac/inguinal arteries, consistent with a urine leak. The right upper quadrant activity represented MAG3 accumulation within the gallbladder.