[Temporal Profiles of Neuroimaging Features of Non-haemorrhagic and Non-ischemic Vertebral Artery Dissections for...

Most patients with non-hemorrhagic and non-ischemic vertebral artery dissections(VADs)are likely to recover with good outcomes. In contrast, some cases of uneventful outcomes have also been reported. Therefore, whether surgical treatment or prolonged follow-up should be utilized for each case remains controversial. In this study, we retrospectively investigated the radiological features and changes in non-hemorrhagic and non-ischemic VADs during the follow-up period. We reviewed the medical records of 15 consecutive patients with VADs without hemorrhage or ischemic lesions diagnosed between 2008 and 2017; all patients reported severe occipital headache. All hemorrhagic and ischemic lesions were categorized into morphological types according to the initial radiological findings. The following morphological types of dissections were observed: six cases, pearl and string type; six cases, dilatation type; two cases, stenosis type; and one case, occlusion type. We observed morphological aggravation in four cases, and among them, three underwent surgical interventions. Seven patients recovered during the follow-up period, and five of them showed marked radiological changes within 2 months. One patient died fromethe clinical onset. Therefore, careful follow-up radiological imaging is presumably necessary for patients with non-hemorrhagic and non-ischemic VADs, within at least 2 months of the clinical onset because of the tendency of VADs for rapid morphological changes during that period.