Presentation
Work up for a chronic headache.
Patient Data
an artery is seen arising from the left cavernous internal carotid artery passing posteriorly and medially to join the basilar artery tip, with the latter giving rise to the normal calibered posterior cerebral arteries. This picture is consistent with a persistent primitive trigeminal artery
the sagittal T1 demonstrates the tau sign
hypoplastic both vertebral arteries, more on the right side
normal calibers of the intra-cranial internal carotid arteries as well as both middle and anterior cerebral arteries
no evidence of aneurysms or AV malformation
Case Discussion
Here is a case of a persistent primitive trigeminal artery - Saltzman type I, one of the persistent carotid-vertebrobasilar anastomoses.