Contrast-enhanced ultrasonography with Sonazoid for diagnosis of gangrenous cholecystitis.

PURPOSE: This prospective study investigated the ability of contrast-enhanced ultrasonography (CEUS) with Sonazoid to diagnose gangrenous cholecystitis and determined the inter-observer agreement.

METHODS: From September 2012 to August 2014, 27 patients with acute cholecystitis underwent preoperative CEUS (registration number 1277). After Sonazoid injection, harmonic imaging of the gallbladder wall was performed, and the findings were recorded using movie clips. The signal intensity was classified as absence (uncomplicated) or presence of perfusion defects (gangrenous). The physician performing CEUS recorded the findings immediately after the examination. Another physician (blinded to the clinical information) then reviewed the movie clips and recorded the findings. The final diagnosis was determined by histological examination in all 27 patients.

RESULTS: The final diagnosis was gangrenous cholecystitis in 15 patients and uncomplicated cholecystitis in 12. On CEUS examination, perfusion defects were detected in 10 patients with gangrenous cholecystitis, giving a sensitivity of 66.7 %, specificity of 100 %, positive predictive value of 100 %, and negative predictive value of 70.6 %. On review of the movie clips, these values were 73.3, 100, 100, and 75.0 %, respectively. The inter-observer agreement between physicians was good (κ coefficient, 0.64).

CONCLUSIONS: CEUS with Sonazoid is a useful and reproducible modality for diagnosing gangrenous cholecystitis.