Diagnostic Value of Somatosensory-Evoked Potential Monitoring During Cerebral Aneurysm Clipping: A Systematic Review

BACKGROUND: Perioperative stroke is a known complication in patients undergoing surgical clipping of cerebral aneurysms. OBJECTIVE: To evaluate whether intraoperative changes in somatosensory-evoked potential (SSEP) monitoring during cerebral aneurysm clipping is diagnostic of perioperative stroke. METHODS: An electronic search of PubMed, Embase, and Web of Science databases was done for studies published through May 2015 on SSEP monitoring in cerebral aneurysm clipping for predicting postoperative outcomes. All titles and abstracts were screened independently on the basis of predetermined criteria. Inclusion criteria included randomized clinical trials and prospective or retrospective cohort reviews; patients with intracranial aneurysms who underwent surgical clipping with intra-operative SSEP monitoring and postoperative neurologic assessment; studies published in English on adult humans >= 18 years with sample size of >= 50; and studies inclusive of an abstract with adequate details on outcomes. RESULTS: A total of 14 articles with a sample population of 2015 patients were analyzed. SSEP monitoring demonstrated a strong mean specificity of 84.5% (95% confidence interval [95% CI] -76.3 to 90.3) but weaker sensitivity of 56.8% (95% CI 44.1-68.6) for predicting stroke. A diagnostic odds ratio of 7.772 (95% CI 5.133-11.767) suggested that the odds of observing an SSEP change among those with a postoperative neurologic deficit were 7 times greater than those without a neurologic deficit. CONCLUSION: Intraoperative SSEP monitoring is highly specific for predicting neurologic outcome after cerebral aneurysm clipping. Patients with postoperative neurologic deficits are 7 times more likely to have had intraoperative SSEP changes. SSEP monitoring may help design prevention strategies to reduce stroke rates after cerebral aneurysm clipping.