Comparison of ultrasonography with computed tomography in the diagnosis of incisional hernias

Abstract

Background The objective of this study is to determine the reliability and validity of ultrasonography (US) in diagnosing incisional hernias in comparison with computed tomography (CT). The CT scans were assessed by two radiologists in order to estimate the inter-observer variation and twice by one radiologist to estimate the intra-observer variation. Patients were evaluated after reconstruction for an abdominal aortic aneurysm or an aortoiliac occlusion. Methods Patients with a midline incision after undergoing reconstruction of an abdominal aortic aneurysm or aortoiliac occlusion were examined by CT scanning and US. Two radiologists evaluated the CT scans independently. One radiologist examined the CT scans twice. Discrepancies between the CT observations were resolved in a common evaluation session between the two radiologists.Results After a mean follow-up of 3.4 years, 40 patients were imaged after a reconstructed abdominal aortic aneurysm (80% of the patients) or aortoiliac occlusion. The prevalence of incisional hernias was 24/40 = 60.0% with CT scanning as the diagnostic modality and 17/40 = 42.5% with US. The measure of agreement between CT scanning and US expressed as a Kappa statistic was 0.66 (95% conWdence interval [CI] 0.45-0.88). The sensitivity of US examination when using CT as a comparison was 70.8%, the speciWcity was 100%, the predictive value of a positive US was 100%, and the predictive value of a negative US was 69.6%. The likelihood ratio of a positive US was inWnite and that of a negative US was 0.29. The inter-and intraobserver Kappa statistics were 0.74 (CI 0.54-0.95) and 0.80 (CI 0.62-0.99), respectively. Conclusions US imaging has a moderate sensitivity and negative predictive value, and a very good speciWcity and positive predictive value. Consistency of diagnosis, as determined by calculating the inter-and intra-observer Kappa statistics, was good. The incidence of incisional hernias is high after aortic reconstructions.

European Hernia Society guidelines on the closure of abdominal wall incisions

“…The PRISMA flow diagram is shown in addendum 3 (Key Question A). Fifteen records were included in the qualitative analysis [3][4][5][6][50][51][52][53][54][55][56][57][58][59][60]. Only four studies were retained as High Quality and are listed in the Summary of Findings table (Table 2) [5, [50][51][52].…”

“…Incisional hernias are a frequent complication of abdominal wall incisions, but a wide range of incisional hernia rates are reported [1][2][3][4][5][6]. The weighted mean incisional hernia rate at 23.8 months was 12.8 % in a systematic review and metaregression study [7], but incidence rates up to 69 % have been reported in high-risk patients with prospective longterm follow-up [8].…”

Surgery-related complications of ventral hernia reported to the Finnish Patient Insurance Centre

“…Inspection and palpation are the main diagnostic methods for hernia, but sometimes radiological imaging is needed (5,8). All hernias causing intense symptoms should be considered for operation because of the risks related to bowel incarceration (6).…”

Dynamic ultrasound with postural change facilitated the detection of an incisional hernia in a case with negative MRI findings

“…Ultrasound has been employed for the survey of hernias since 1980 [9] and current research indicated a moderate sensitivity (70.8 %) and an excellent specificity (100 %) for incisional hernia detection by using CT findings as the golden standard [10,11]. Ultrasound scanning combined with palpation for abdominal walls with forceful attempted exhalation was suggested to improve the detection rate [12].…”