Abnormalities of the perinephric fascia and fat in pancreatitis.

CT may reveal inflammatory thickening of the retroperitoneal fascial membranes and edema or lipolysis of the retroperitoneal fat resulting from acute pancreatitis. Retrospective analysis of the perinephric space in 16 normal individuals gave values of 1-3 mm for perinephric fascial thickness and -132 to -92 H for perinephric fat density. Scans of 15 patients with pancreatitis demonstrated fascial thickening in 46% compared with 5% of normal individuals, while 27% had increased fat density compared with 6% of the normal population. An abnormal CT appearance of the retroperitoneal fascia or fat can be a sign of pancreatitis.