The clinical significance of evaluating vertebral artery intracranial stenotic lesions

Abstract

Objective To evaluate the correlation between intracranial vertebral artery (VA) stenotic lesions at different locations and posterior circulation ischemia (PCI) symptoms.Methods The present study included 362 cases of patients with unilateral VA severe stenosis or occlusion confirmed by carotid Doppler ultrasonography,CT angiography and (or) digital subtraction angiography.According to the relationship between the location of stenotic lesion and posterior inferior cerebellar artery (PICA),all cases were divided into pre-PICA group (n=73) and post-PICA group (n=289).According to presentation of PCI symptoms,all cases were divided into symptomatic group (n=133) and asymptomatic group (n=229).On CDFI,hemodynamic parameters were analyzed and recorded,which included the peak systolic velocity (PSV),end diastolic velocity (EDV),resistance index (RI) and VA diameter (VAD) and spectrum shape.And the correlation between location of intracranial VA stenosis / occlusion and PCI symptoms was evaluated.The hemodynamic parameters of bilateral intervertebral segments were compared in patient with unilateral intracranial VA stenosis by paired t test.The ipsilateral intervertebral segment hemodynamic changes were compared among patents with different locations of unilateral intracranial VA stenosis by using independent sample t test.Using 2 × 2 crosstables and Pearson 22 test,the correlation between the location of VA stenosis and PCI symptoms was analyszed.Results Hemodynamic parameters of VA were associated with its stenotic location to PICA.The comparison of the ipsilateral and contralateral VA showed that PSV,EDV and RI,VAD had significant difference (43.97± 1.22 vs 55.82± 1.08,6.35±0.23 vs 19.41 ±0.48,0.850±0.004 vs 0.640± 0.005,2.75 ± 0.04 vs 4.00± 0.03),difference was statistically significan (t=-7.086,-23.754,-32.603,23.842,all P ＜ 0.001).The intervertebral segment PSV,EDV and RI of ipsilateral VA were significantly related to the stenotic location to PICA (t=-6.665,-17.459,22.143,P＜0.001),but not for VAD (P＞0.05).In pre-PICA group,the intervertebral segment spectrum of ipsilateral VA was unimodal-style,while in post-PICA group the spetrum was high-resistance-style.VA intracranial severe stenosis at different locations was not associated with the symptoms of PCI (r=0.023,P=0.782),while VA intracranial occlusion at different locations was associated with the symptoms of PCI significantly (r=0.792,P ＜ 0.05).Conclusions CDU is a non-invasive,real-time and dynamic assessment tool for VA intracranial lesions in different locations,which can provide reliable information for clinical treatment and prognosis prediction.