Comparative Analysis of Somatosensory-evoked Potentials and Transcranial Doppler Ultrasound for Cerebral Ischemia Detection in Carotid Endarterectomy: Insights from Network Meta-Analysis and Clinical Data.

OBJECTIVE This study aims to compare the diagnostic efficacy of somatosensory-evoked potentials (SEP) and transcranial Doppler sonography (TCD) for monitoring cerebral tissue ischemia during carotid endarterectomy (CEA) using network meta-analysis and retrospective analysis of clinical data. METHODS For the meta-analysis, we conducted a comprehensive search of four electronic databases (PubMed, EMBASE, Cochrane, and Web of Science) from inception to September 2023, resulting in the inclusion of 52 relevant articles. Additionally, a retrospective study was conducted at our hospital, involving patients who underwent CEA surgery from July 2019 to July 2021. RESULTS The network meta-analysis incorporated 52 articles, with ranking results indicating that SEP demonstrated superior performance in specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy , with surface under the cumulative ranking curve (SUCRA) values of 99.9%, 93.8%, 96.6%, and 99.9%, respectively. Furthermore, TCD exhibited the highest sensitivity with a SUCRA value of 92.0%. A total of 190 patients meeting inclusion criteria were included in the retrospective study. The area under the curve (AUC) for SEP's receiver operating characteristic (ROC) curve was 0.787, compared to TCD's AUC of 0.606. SEP demonstrated a sensitivity of 66.67%, with a specificity of 90.76%, PPV of 19.05%, NPV of 98.82%, and accuracy of 90%. For TCD, the diagnostic performance measures included a sensitivity of 50.00%, specificity of 71.19%, PPV of 5.35%, NPV of 97.76%, and accuracy of 70.53%. The Fisher's exact test for sensitivity yielded a result of P=1.000. The χˆ2 test for specificity resulted in χˆ2=22.863, with P<0.001. Continuous correction χˆ2 tests for PPV and NPV showed χˆ2=2.005 (P=0.157) and χˆ2=0.069 (P=0.793), respectively. Additionally, the χˆ2 test for accuracy showed χˆ2=22.742, with P<0.001. CONCLUSIONS During CEA, SEP appears to provide a slightly more reliable indication of the ischemic condition in cerebral tissues compared to TCD.