Answer

Acute Cortical Necrosis – Reverse Rim Sign
Non-contrast CT in the axial plane in a 58 -year-old patient, following contrast administration now with acute renal failure. The CT shows persistent a small right scarred kidney in the excretory phase and an enlarged left kidney with a reverse rim sign. The right kidney has a relatively low-density cortex compared to the hyper enhanced medulla. This finding known as the reversed rim sign is characteristic of acute cortical necrosis Contrast is present left renal pelvis. There is significant thickening of the stomach with ascites and suggestion of omental cake and a diagnosis of gastric cancer with omental metastases is a prime consideration
Ashley Davidoff MD TheCommonVein.net 19759