Benefits of sonography in diagnosing suspected uncomplicated acute diverticulitis.

Objectives: Despite evidence demonstrating equivalent accuracy of sonography and computed tomography (CT) in the workup of mild/uncomplicated acute diverticulitis, CT is overwhelmingly performed as the initial diagnostic test, particularly in the acute setting. Our study evaluated potential radiation and turnaround time savings associated with performing sonography instead of CT as the initial diagnostic examination in the workup of suspected uncomplicated acute diverticulitis.

Methods: We retrospectively reviewed medical records from January 2010 to December 2012 for patients presenting with clinical symptoms of acute diverticulitis. Patients were categorized as a whole and subgrouped by age (>40 and <40 years). A modified Hinchey classification (Am Surg 1999; 65:632-636) was used to stage the severity of the disease. The effective radiation dose was calculated by multiplying the dose length product from the scanner by the standard conversion coefficient (k= 0.0021 mSv/mGy × cm). The turnaround time for patients was calculated as the time the examination was ordered by the emergency department physician or staff to the time the report was finalized.

Results: Our study included 253 patients (172 male and 81 female; mean age ± SD, 50.2 ± 11.7 years; 132 >40 years and 121 <40 years). The distribution of patients by the modified Hinchey classification was 210 (stages 0 and 1a), 26 (stages 1b and 2), 17 (stages 3 and 4), 0 (fistula), and 0 (obstruction). The estimated CT radiation dose per patient was 21 ± 5.2 mSv. Mean turnaround times for CT and sonography were 138.5 ± 76.9 and 51.3 ± 44 minutes, respectively.

Conclusions: Sonography is a lower-cost, faster, and radiation-free alternative that measures up to the diagnostic standards of CT for management of suspected mild or uncomplicated acute diverticulitis.