Ultrasonography is the preferred first-line imaging modality for diagnosing cholecystitis [1]. Point-of-care-ultrasound (PoCUS) is comparable to ultrasound performed by radiology (RADUS) in diagnostic accuracy for cholecystitis [2,3]. The sonographic findings suggestive of cholecystitis include gallstones, especially a stone-in-neck (SIN), sonographic Murphy sign (SM), wall thickening, and pericholecystic fluid [4,5].

Gallbladder distention, defined as ≥10 cm by ≥4 cm, is not typically evaluated on PoCUS. This is likely due to changes in gallbladder size with prandial state, and a presumed wide differential for biliary distention that spans many diagnoses other than cholecystitis. However, distention on RADUS may suggest more severe cholecystitis and longer operative times [[6], [7], [8], [9], [10]]. Given PoCUS is generally performed hours before RADUS in the Emergency Department (ED) setting [11], it is unclear whether distention on PoCUS carries the same implications. The value of distention has not previously been investigated for PoCUS and may represent an underutilized sonographic sign of cholecystitis.

The primary aim of this study was to determine the test characteristics of distention on PoCUS for cholecystitis (acute or chronic), using inpatient intervention for cholecystitis as the reference standard. Our secondary aims were to determine whether distention on PoCUS was associated with a) SIN, b) acute cholecystitis on pathology, and c) longer cholecystectomy operative times.