Penumbra volume predicts unfavorable outcome in patients with acute minor stroke or transient ischemic attack.

BACKGROUND: A subgroup of patients with acute minor stroke (AMS) or transient ischemic attack (TIA) become disabled due to disease progression (DP) or recurrent stroke within three months. To identify the risk factors for DP in AMS/TIA patients. In the literature, no studies focused on computed tomography perfusion (CTP) in AMS/TIA patients at the acute stage. METHODS: This retrospective study included patients with AMS or TIA (onset of symptoms ≤ 4.5 hours, baseline NIHSS score of 0 to 4). Disease progression (DP) was defined as a deterioration of NIHSS score of ≥ 2 points during hospitalization or mRS ≥ 2 at 3-months follow-up. Clinical data and imaging results were retrieved and measured for statistical analysis. RESULTS: From 2011 to 2017, total 135 patients were eligible for further analysis: 28 patients (20.7 %, DP group) and 107 patients (79.3%, Non-DP group). The DP group had significantly higher larger penumbra volumes (p = 0.028). In univariate model of the logistic regression, patients with the following risk factors tended to have unfavorable outcome: female gender, higher HbA1c, CKD stage ≥ 3b, intracranial atherosclerosis, and penumbra volume were associated unfavorable outcome, but larger deadcore volume was not. In further multivariate analysis, only penumbra volume > 5cm (p = 0.049, OR = 3.21, 95% CI: 1.00 to 10.27) had the statistical significance. The cut-point value of the penumbra volume for unfavorable outcome in AMS/TIA patients was 4.73 cm. CONCLUSION: One fifth of the AMS/TIA patients had unfavorable outcome at 90 days. In CTP performed within 4.5 hours after the onset of AMS/TIA, the penumbra volume (> 5 cm) was a significant risk factor for DP, and the cut-point value was 4.73 cm. Further studies could be designed to involve this subgroup of patients for more aggressive treatment.