Preoperative diagnosis of gangrenous acute cholecystitis: usefulness of CEUS

Abstract
To evaluate CEUS for the preoperative diagnosis of gangrenous acute cholecystitis. This prospective study was approved by our institution’s ethical committee. Fifty-six patients who underwent both US and CEUS and were confirmed as presenting with acute cholecystitis at pathology were included. Clinical data, mean time until surgery, macroscopic appearance of the GB, and the presence of gangrene at pathology were noted. Baseline US images and CEUS cine clips were analyzed by two experienced radiologists. Statistical analyses were performed. Gangrenous acute cholecystitis was diagnosed in 23 (41%) patients and uncomplicated acute cholecystitis in 33 (59%). Patients with gangrenous acute cholecystitis were found to be older (p = 0.048). Mean time from CEUS to surgery was found to be shorter in patients presenting with gangrenous acute cholecystitis (p = 0.052). At US, GB short axis ≥4 cm (p = 0.039) and GB wall interruption (p = 0.037) showed a statistically significant association with the diagnosis of gangrenous acute cholecystitis. On CEUS, discontinuous or irregular GB wall enhancement was reported in 19/23 (83%) patients with gangrenous acute cholecystitis and showed association with the presence of gangrene at pathology (p = 0.001). The interobserver agreement for the presence of discontinuous or irregular GB wall enhancement on CEUS images was good. Performing CEUS on patients presenting with US findings of acute cholecystitis is relevant, since the presence of a discontinuous or irregular enhancement of the GB wall appears to be correlated with the diagnosis of gangrenous acute cholecystitis.