Perfusion by delayed time to peak in vertebrobasilar dolichoectasia patients with vertigo.

OBJECTIVE

To investigate the association between the perfusion magnetic resonance imaging (MRI) and vertebrobasilar dolichoectasia (VBD) in vertigo patients and at least one vascular risk factor.

METHODS

We studied 289 patients with vertigo (spinning, swaying, nausea, vomiting, and unsteady gait) who performed multimode MRI. Maximum diameter and tortuous parameters of the basilar artery and vertebral arteries were calculated using magnetic resonance angiography. Relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), mean transit time (MTT), and time to peak (TTP) maps were evaluated by dynamic susceptibility contrast-enhanced perfusion imaging. Association of perfusion MRI and VBD was evaluated by nonparametric tests and receiver-operating characteristic curve was constructed to predict posterior ischemic stroke in VBD patients.

RESULTS

The prevalence of VBD was 26.6% ( = 77/289) in our study. Male gender was the risk factor of VBD by multivariate analysis. BA diameter was significant statistics between ischemic stroke and nonischemic stroke patients. TTP in bilateral lower cerebellum, superior cerebellum, bilateral pons, and occipital and temporal lobes region of interests was significantly delayed in VBD versus non-VBD patients, while rCBF, rCBV, and MTT parameters were not significant differences. TTP in the right temporal lobe delayed by 21.96 ms was the best predictive value and the mean TTP predictive threshold value in all ROIs was 22.67 ± 1.48 ms.

INTERPRETATION

VBD leads to the hypoperfusion of posterior circulation territory characterized by delayed TTP. Delayed TTP in cerebellum, pons, and occipital and temporal lobes fed by vertebrobasilar arteries predicted the occurrence of posterior ischemic stroke in VBD patients.