ABSTRACT
Vertebral artery hypoplasia (VAH) can be easily overlooked if the contralateral side vertebral artery is intact, because of compensation by the contralateral artery or cerebral collateral network. The clinical relevance and hemodynamic impact of VAH is still controversial. However, VAH has recently been considered a risk factor for posterior circulation ischemia. Ischemic stroke is seldom caused by free floating thrombi (FFT) in the artery. Pathophysiology of FFT has not yet been clarified. The state of reduced blood flow such as a vertebral artery origin stenosis may cause FFT. Their instability may make them sources of recurrent artery to artery embolism. Patients with FFT will require appropriate medical and endovascular treatment. The current case illustrates a short-term angiographic change of spontaneous thrombolysis of VAH and multiple thrombi at the distal region of the stenosed lesion after stent-assisted angioplasty for a vertebral artery origin stenosis.