Vertebrobasilar insufficiency by persistent trigeminal artery stenosis

Persistent trigeminal artery is an embryonic remnant of the anastomotic channel linking the internal carotid artery and the basilar artery. Cases of vertebrobasilar insufficiency caused by the p ersistent trigeminal artery with internal carotid artery stenosis has been described previously, but vertebrobasilar insufficiency entirely due to in situ stenosis of the p ersistent trigeminal artery has not been reported. A 71-year-old man presented with frequent dizzy episodes. The brain MRI showed no parenchymal lesions. MR angiography showed poor visualization of vertebrobasilar system. He was diagnosed as having vertebrobasilar insufficiency . Cerebral angiography revealed that there was complete occlusion at the vertebrobasilar junction, and the basilar artery was supplied by the persistent trigeminal artery which had severe stenosis at its origin. There was no stenosis of the internal carotid artery of both sides. We believe that this is the first report of vertebrobasilar insufficiency due to stenosed persistent trigeminal artery, without internal carotid artery stenosis.