Trigeminal artery and its clinical importance

Abstract

The trigeminal artery can be seen during embryonic development. This artery supplies the basilar artery. The tri­geminal artery involutes after the posterior communicating artery develops. In some cases, the artery becomes permanent and causes medical complications, especially intracranial aneurysms. The trigeminal artery arises from the internal carotid artery when the embryo is 6 weeks old. It is responsible for the supply of this region before other arteries develop. It involutes when the posterior communicating artery aris­es from the internal carotid artery. Normally, the artery`s length of existence is 7-10 days. Sometimes this artery continues to exist in adulthood. In this case this structure is named persistent trigeminal artery (PTA). The clinical conditions associated with the trigeminal artery are as follows: ectasia and fenestration of the an­terior communicating artery (ACA), infraoptic part of the A1 segment of ACA, occluded internal carotid artery (ICA), absence of the common carotid artery and both ICAs, hypoplastic basilar artery (BA) and vertebral artery (VA), bilateral occlusion of VA, primitive otic artery and PHACE syndrome. There are many reports about aneu­rysms being a result of the presence of PTA. The prevalence is approximately 3%. In patients with PTA, occlusion of PTA leading to a decreased blood flow in the BA can be found. Carotid-cavernous fistula and PTA-cavernous si­nus fistula can be idiopathic or traumatic. In this context the Klippel-Feil syndrome, Moyamoya disease as well as infratentorial and supratentorial AVMs have been reported. PTA may be associated with cerebral syndromes and disorders. It has clinical importance that should be considered during clinical examination.