The value of the ucN13-P15 interpeak latency predicted acute posterior circulation ischemia and the chronic outcome.

OBJECTIVE: To determine the sensitivity and specificity of the ucN13-P15 (CV2-Fz) and IcN13-P15 (CV7-Fz) interpeak latencies when used to predict acute posterior circulation ischemia. METHODS: A total of 426 consecutive patients who were hospitalized within 3 days of the onset of stroke were prospectively enrolled in the study. Of these patients, 110 had infarct lesions in the posterior circulation territory. The ucN13-P15 and IcN13-P15 interpeak latencies on admission were assessed, and the chronic outcome was assessed at 3 months. RESULTS: The ucN13-P15 and IcN13-P15 interpeak latencies (both P < 0.001) were prolonged in patients with posterior circulation ischemia than in those with anterior circulation ischemia. The optimal cutoff score of the baseline ucN13-P15 IPL (≥ 3.35 milliseconds) had a sensitivity of 76.8% and a specificity of 79.9%. The IcN13-P15 IPL (≥ 4.225 milliseconds) had a sensitivity of 56.1% and a specificity of 93.2%. CONCLUSIONS: The ucN13-P15 interpeak latency must be appraised in light of its diagnostic value in acute posterior circulation ischemia. However, the ucN13-P15 interpeak latency was not independently predictive of a favorable outcome.