Lea Chen

The sonographic diagnosis of acute cholecystitis presents challenges. In our practice, we enhance diagnostic accuracy by determining a patient’s risk of acute cholecystitis using four non-image parameters and five imaging parameters. The non-image risk assessment is based on patient age, sex, leukocytosis, and the presence of a sonographic Murphy sign. The imaging risk stratification is derived from evaluating gallbladder (GB) distention, GB wall thickness, GB contents, pericholecystic irregular collections, and hepatic artery peak systolic velocity (HAv). By applying a standardized scoring framework, patients are stratified into one of four diagnostic categories for acute cholecystitis: (1) practically excluded (< 1% probability); (2) reduced risk (< 10% probability); (3) elevated risk (25–30% probability); (4) substantially elevated risk (with three subgroups having 50%, 75%, and 90% probability). This review outlines the methodology of our approach, provides supporting data from published cohorts, and explains the macro-enabled Excel tool we use to streamline the analysis. This tool generates standardized report and impression statements that can be directly incorporated into radiology reporting templates. The approach promotes consistency in reporting, particularly amongst trainees formulating preliminary interpretations, and offers consistent evidence-based probability estimates to emergency department physicians and surgeons for clinical decision-making using a framework that eliminates indeterminate assessments. Graphical Abstract

Purpose Compare HAv to non-Doppler ultrasound observations for diagnosing acute cholecystitis in a large consecutive cohort of emergency department (ED) patients and establish a method to combine HAv assessment with non-Doppler observations for diagnosing acute cholecystitis. Methods Consecutive ED patients at one institution undergoing gallbladder (GB) ultrasound (US) for acute cholecystitis between 1/1/2020 and 8/31/2022 had assessments of GB diameter, GB wall thickness, GB contents, pericholecystic irregular collection, and hepatic artery peak systolic velocity (HAv). The non-Doppler observations were scored and summed. Non-Doppler risk categorization was based on rate of acute cholecystitis associated with summed scores. The impact of HAv stratification on the rate of acute cholecystitis in the non-Doppler risk categories was evaluated, with regrouping when subgroups had changes in the acute cholecystitis rate; the regrouping established the HAv-adjusted risk model. Receiver-operator curves for acute cholecystitis diagnosis for individual parameters, the non-Doppler risk categorization, and the HAv-adjusted risk model were compared using area-under-curve (AUC) calculations. Results Of the 885 patients in the study cohort, 117 (13.2%) had acute cholecystitis. The AUC for diagnosing acute cholecystitis using GB distention (83.8%, p < 0.001), GB wall thickness (79.1%, p < 0.001), and GB contents (75.0%, p 0.02) were higher than HAv (66.3%). HAv assessment adjusted risk for 195 patients. The non-Doppler risk categorization and the HAv-adjusted risk model had the same sensitivity (84.6%) and specificity (85.2%) for diagnosing acute cholecystitis, but the HAv-adjusted risk model showed higher AUC (91.3%, p 0.03) due to increased ability to exclude acute cholecystitis. Conclusions The diagnostic performance of HAv for acute cholecystitis was lower than other assessments. A categorization scheme based on summed points assigned to each non-Doppler observation was improved with HAv assessment. This risk categorization approach using formulaic integration of non-Doppler and Doppler assessments on ED patients allows radiologists to convey one of five levels of disease probability based solely on sonographic features ranging from effectively excluding acute cholecystitis to substantially elevating the chance the patient has the condition.