“…About one century elapsed until the artery was angiographically demonstrated for the first time by Sutton in an article published in the British Journal of Radiology in 1950 (75). Persistent trigeminal artery (PTA) is the most common of the primitive carotid-basilar anastomoses that persist into adulthood, with an estimated incidence of 0.1 to 1.0% on cerebral angiograms (17,20,36,39,47,52,67,70). A number of cases of PTA and its variants found at autopsy (21,30, 34,52,60,67,70,82), on cerebral angiograms (2,6,7,17,27, 35,73,85), and on MRI and MRA scans (7,18,63) demonstrate the anatomy (30,39,52,67) of this primitive anastomosis and its relationship to various vascular diseases (1,16,19,20,25,30,36,44,47).…”