Meta-analysis of the accuracy of contrast-enhanced ultrasound for the detection of endoleak after endovascular aneurysm repair

Objective: The purpose of this systematic review and meta-analysis was to investigate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) for detection of endoleak after endovascular aneurysm repair (EVAR). Methods: We searched electronic bibliographic databases for original articles comparing concurrent CEUS and computed tomography angiography for detection of endoleak after EVAR. We assessed the methodologic quality of the studies with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. We constructed 2 x 2 contingency tables for all selected studies including true-positive, false-positive, false-negative, and true-negative results for all endoleaks and for type I and type III endoleaks. We used a mixed-effects logistic regression model to estimate summary sensitivity and specificity. We developed hierarchical summary receiver operating characteristic curves and calculated the area under the curve (AUC). Results: We identified 26 studies reporting a total of 2638 paired scans in 2217 patients. The major risk of bias of the selected studies pertained to blinding for the index test and the reference standard. The pooled sensitivity and specificity of CEUS for all endoleaks were 0.94 (95% confidence interval [ CI], 0.89-0.97) and 0.93 (95% CI, 0.89-0.96), respectively. The AUC was 0.98 (95% CI, 0.93-0.99). The summary estimate of sensitivity and specificity for type I and type III endoleaks was 0.97 (95% CI, 0.8-1.00) and 1.00 (95% CI, 0.99-1.00), respectively. The AUC was 1.00 (95% CI, 0.99-1.00). Conclusions: CEUS has a high sensitivity and specificity in the detection of endoleaks after EVAR. CEUS is a useful tool in EVAR surveillance.