18) orty eight after sustaining a blunt abdominal injury, a 15 | Surgery videos & books

18) orty eight after sustaining a blunt abdominal injury, a 15 years old by presents with hematuria and pain in the left side of abdomen. On examination, he has a pulse rate of 96/ minute with a BP of 110/70 mm Hg. His Hb is 10.8 gm% with
a PCV of 31%. Abdominal examination revealed tenderness in left lumbar region but no palpable mass. The most appropriate investigation to diagnose and find the extent of renal injury would be: