Anatomical features and clinical relevance of a persistent trigeminal artery

Abstract

Background: Although persistent trigeminal artery (PTA) is uncommonly identified, knowledge of this structure is essential for clinicians who interpret cranial imaging, perform invasive studies of the cerebral vasculature, and operate this region.

Methods: A review of the medical literature using standard search engines was performed to locate articles regarding the PTA, with special attention with anatomical descriptions.

Results: Although anatomical reports of PTA anatomy are very scarce, those were analyzed to describe in detail the current knowledge about its anatomical relationships and variants. Additionally, the embryology, classification, clinical implications, and imaging modalities of this vessel are extensively discussed.

Conclusions: Through a comprehensive review of isolated reports of the PTA, the clinician can better understand and treat patients with such an anatomical derailment.

Keywords: Carotid-basilar anastomosis; fetal intracranial artery; persistence; trigeminal artery; vascular anatomy.

Figure 1

Selective right internal carotid angiography showing persistent trigeminal artery (black arrows) on anteroposterior view (a) and lateral view (b)

Figure 2

Origin of the artery is identifiable at posterolateral wall of intracavernous segment of internal carotid (IC). It courses adjacent to lateral wall of cavernous sinus, closely related with abducens nerve (VI), which passes over the artery in an oblique direction toward the superior orbital fissure. The ophthalmic branch of trigeminal nerve (V) faces medially with its lateral side. In this specimen, it became extradurally through a channel delimited superiorly by the posterior petroclinoid ligament and inferiorly by a groove of the lateral side of dorsum sellae (DS). Oculomotor nerve (III)

Figure 3

Three-dimensional computed tomographic (CT) angiography showing a lateral petrosal variant of persistent trigeminal artery (PTA) as it exits immediately superior to the cranial end of petroclival fissure; just medial to Meckel's cave and closely related with the ophthalmic branch of trigeminal nerve. It courses posterior and medially to reach the basilar artery before its bifurcation. It relationships with posterior communicating artery (PcomA) and anterior choroidal artery (AchoA) are also showed