Diagnostic Values Of Subtracted CTA On Intracranial Aneurysms: A Systemic Review

Purpose:To perform a systemic review on the diagnostic values of subtracted CTA on intracranial aneurysms by means of meta-analysis.Methods:Through a computerized searching and handsearching of relevant articles about subtracted CTA on intracranial aneurysms diagnosis, information and data of areticles that met the setting criteria were extracted. Methodological quality was assessed based on the QUADAS-2 tool. Through meta-analysis, reviewer calculated the pooled sensitivity and the pooled specificity of subtracted CTA repectively, drew the SROC and estimated the AUC, performed subgroup analysis on different DSA as reference standard on per anerysm, per patient and per micro aneurysm basis, respectively. Likelihood ratio scattergram was established to evaluate the diagnostic informativeness of subtracted CTA. The publish bias were assessed by the funnel plot and Egger’s test.Methods:1361 patients in 9 articles were finnally included, of which the overall methodological quality was high. Totally,1032 patients with 1207 intracranial aneurysms were detected by DSA. On per anerysm basis, the pooled sensitivity was 0.991[95%CI (0.971-0.997)], the pooled specificity was 0.996[95%CI (0.891-1.000)], the AUC was 1.00[95%CI (0.99-1.00)]. On per patient basis, the pooled sensitivity was 0.993[95%CI (0.976-0.998)], the pooled specificity was 0.993[95%CI (0.913-0.999)], the AUC was 1.00[95%CI (0.99-1.00)]. On per mico anerysm basis, the pooled sensitivity was 0.961 [95%CI (0.898-0.986)], the pooled specificity was 0.993[95%CI (0.921-0.999)], the AUC was 0.99[95%CI (0.98-1.00)]. In subgroup analysis, accuracy of subtracted CTA was consistent with 2D-DSA; while compared to 3D-DSA as reference, sensitivity and specificity of subtracted CTA decreased, without obvious diference from that refered to 2D-DSA. Likelihood ratio scattergram indicated a high informativeness of subtracted CTA in diagnosing or excluding intracranial aneurysm. Funnel plot and Egger’s test showed the publish bias were low.Conclusion:Subtracted CTA has a very high diagnostic value on intracranial aneurysms, and can replace 2D-DSA to rule out the responsible aneurysm for patient with relevant symptoms. When diagnosis is unclear on subtracted CTA, especially on the micro aneurysms,3D-DSA is recommended for a confirmation. Subtracted CTA can accurately guide the treatment strategy for aneurysms.