Variations in the intracranial vertebrobasilar system:a CT angiography study / 国际脑血管病杂志

ABSTRACT

Objective To evaluate the valuations of the intracranial vertebrobasilar arteries using CT angiography (CTA) in order to improve the understanding of various variants in intracranial vertebrobasilar arteries.Methods The CTA images of 435 subjects were analyzed retrospectively.The data were collected by a 16-slice CT scanner.All the CTA images were processed technically by the maximum intensity projection and volume rendering.The intracranial vertebrobasilar arteries were measured and analyzed.Results Among the 435 subjects,bilateral intracranial vertebral arteries (V4) showed symmetry in 183 (42.07％) and dissymmetry in 252 (57.93％).Hypoplasia were found in 27 subjects (6.21％) on the left V4 segments and 36 (8.28％) on the right V4 segments,and a total of 21 (4.83％) were directly continued as the ipsilateral posterior inferior cerebellar arteries on the unilateral V4 segments.There were 2 subjects (0.46％) with vertebrobasilar dolichoectasia.There were 32 subjects (7.36％) had fenestration variation,3 of them (0.69％) were on the V4 segments,10 (2.30％) at the junctions,and 19 (4.37％) in the basilar arteries.Two subjects (0.46％) had persistent trigeminal arteries.Conclusions The variations of intracranial vertebrobasilar arteries mainly include angiodysplasia,vertebrobasilar dolichoectasia,fenestration variation,and persistent trigeminal artery.As a noninvasive vascular imaging method,CTA may accurately and visually assess the anatomic variation of intracranial vertebrobasilar artery,and provide imaging guidance for the preoperative evaluation of posterior fossa surgery.