Dynamics of Ultrasound Findings in Acute Cholecystitis

Abstract Background: Abdominal ultrasound is the first-line imaging modality for diagnosing acute cholecystitis. While sonographic criteria for acute cholecystitis are well established, their temporal dynamics and correlation with disease severity remain poorly understood. This study aimed to explore the time course of ultrasound findings in acute cholecystitis. Methods: Between November 2017 and October 2018, patients admitted with acute cholecystitis fulfilling the Tokyo Guidelines were prospectively enrolled. All patients received standard care and underwent an initial abdominal ultrasound at admission. Daily follow-up scans were planned until cholecystectomy or discharge. Patients with at least two ultrasound exams were included in the final analysis. Parameters assessed included gallbladder wall thickness and volume, as well as mural and pericholecystic edema. All exams followed a standardized protocol and were performed by certified ultrasound specialists. Results: A total of 120 patients were enrolled. Of these, 88 underwent at least one ultrasound examination, and 37 received two or more scans and were included in the final analysis. Gallbladder wall edema was present in all but one case and remained stable over time. Mean gallbladder wall thickness and volume showed minimal changes, with a slight reduction in volume during the 1 st days. Substantial intraindividual variability in gallbladder volume and wall thickness was observed, independent of disease severity. Conclusion: Sonographic criteria for acute cholecystitis remain stable over time, suggesting that the timing of ultrasound does not affect diagnostic accuracy. However, substantial individual variability limits their use for risk scoring or severity grading, highlighting the need for complementary diagnostic approaches.