Importance: Previous work has demonstrated that dynamic abdominal sonography for hernia (DASH) is accurate for the diagnosis of incisional hernia. The usefulness of DASH for characterization of incisional hernia is unknown.
Objective: To determine whether DASH can be objectively used to characterize incisional hernias by measurement of mean surface area (MSA).
Design, setting, and participants: A prospective cohort study was conducted. A total of 109 adults with incisional hernia were enrolled between July 1, 2010, and March 1, 2012. Patients with a stoma, fistula, or soft-tissue infection were excluded.
Interventions: DASH was performed by a surgeon to determine the maximal transverse and craniocaudal dimensions of the incisional hernia. A separate surgeon, blinded to the DASH results, performed the same measurements using computed tomography (CT).
Main outcomes and measures: The MSA was calculated, and the difference in MSA by DASH and CT was compared using the Wilcoxon signed rank test. Subset analysis was performed with patients stratified into nonobese, obese, and morbidly obese groups. We hypothesized that there was no significant difference between MSA as measured by DASH compared with CT.
Results: A total of 109 patients were enrolled (mean age, 56 years; mean body mass index, 32.2 [calculated as weight in kilograms divided by height in meters squared]; and 67.0% women). The mean (SD) MSA measurements were similar between the modalities: DASH, 41.8 (67.5) cm2 and CT, 44.6 (78.4) cm2 (P = .82). The MSA measurements determined by DASH and CT were also similar for all groups when stratified by body mass index. There were 15 patients who had a hernia 10 cm or larger in transverse dimension. The mean body mass index of this group was 39.2, and the MSA measurements by DASH and CT were similar (P = .26).
Conclusions and relevance: DASH can be used to objectively characterize hernias by MSA, with accuracy demonstrated in the obese population and in patients whose hernias were very large (≥10 cm in diameter). DASH offers the advantages of real-time imaging and no ionizing radiation and may obviate the need for the patient to schedule additional imaging appointments.