Fig. 2
From: Diverticulitis: a comprehensive review with usual and unusual complications
Seventy-two-year-old female with free perforation complicating diverticulitis. Axial contrast enhanced CT images at parenchymal window (a) and bone window (b) demonstrate a ‘dirty mass’ (arrows) formed by stool nearby sigmoid colon diverticulitis. Free air (arrowheads) and inflammatory fat stranding resulting from perforation of diverticulitis are seen posterior to the pararenal fascia