Study Of Hyperdense Basilar Artery Sign In Early Diagnosis Of Acute Posterior Circulation Stroke And Prediction Of Short-term Outcome

PurposeOur aim was to determine whether the hyperdense basilar artery sign (HDBA) has utility in early diagnosis of acute posterior circulation stroke and prediction of short-term outcome.Materials and methodAll the acute posterior circulation stroke inpatients from October.1,2008 to October.1,2009 were collected in our research. Three clinical neurologist and neuroradiologists blinded to clinical outcome and results of magnetic resonance imaging (MRI) examined unenhanced computed tomography scans for the HDBA sign and materials were classified into two groups according to this sign. Short-term outcome was measured by the 15th National Institute of Health Stroke Scale (NIHSS) scores. T-tests were used for comparison of continuous variables of normal distribution, and Mann-Whitney U tests were used for comparison of nonparametric distributions. Correlation with short-term outcome was performed using either Pearson or Spearman correlations. For categorical variables,χ2 or Fisher exact tests were used for group comparison, while univariate analyses were assessed using Mann-Whitney U tests. Variables with P<0.1 upon univariate analysis were included in the multiple regression analysisResultsOne hundred and twenty-six cases of acute posterior circulation stroke were included in the study. Of all the ischemic stroke patients,31 cases were included in positive HDBA group. No statistically significant differences were found in risk factors of ischemic stroke, except atrial fibrillation (P=0.025). Admission and discharge NIHSS scores in the positive HDBA group were significantly higher than scores for the negative HDBA group (P=0.0010.002, respectively). The infarction territory for the positive HDBA group was mainly multi-region in nature (51.6%, P＜0.001), while the negative HDBA group showed mainly middle territory infarction. Significant independent predictors of short-term outcome included the HDBA sign (P<0.001) and admission NIHSS scores (P＜0.001).Conclusion1. Approximately half of the HDBA patients showed multi-region infarction and a serious neurological symptom, especially in proximal-middle territory and proximal-middle-distal territory; 2. The HDBA sign was independent predictor of short-outcome in acute posterior circulation stroke inpatients; 3. In patient presenting with manifestation of posterior circulation stroke, the HDBA sign on unenhanced CT might predict basilar artery thrombosis.