- Case report
- Open Access
Persistent trigeminal artery in a patient with posterior circulation stroke treated with rt-PA: case report
BMC Neurology volume 19, Article number: 257 (2019)
A persistent trigeminal artery (PTA) is a non-involuted embryonic vessel that connects the cavernous part of the internal carotid artery with the posterior circulation. In the adult it is associated with multiple pathological conditions including trigeminal neuralgia, ophthalmoplegia, hypopituitarism, intracavernous fistula, brain aneurysms and posterior circulation strokes. The latter may occur through steal phenomena or thrombosis in the anterior circulation. PTA associated vertebrobasilar hypoplasia has yet to be associated to TIA like events, however, in the reported case, that seems to be the case with reported vertigo being probably linked to vertebrobasilar insufficiency.
We present a case of an 82-year-old man with sudden onset neurological deficits, including left hemiparesis with crural predominance, vertical nystagmus, right internuclear ophthalmoplegia, dysarthria and dysmetria on the left arm. CT angiography disclosed basilar artery hypoplasia in the proximal two thirds and a persistent trigeminal artery. He was diagnosed with acute ischemic stroke. He was submitted to rt-PA with partial reversion of deficits.
The ischemic events related to PTA remain a rare cause of stroke with specific pathophysiological mechanisms and implications. They may occur through steal phenomena or thrombosis in the anterior circulation. Upon literature review, in the described case both mechanisms seem possible, however the transient episodes of vertigo could have been the first sign of vertebrobasilar insufficiency.
The trigeminal arteries have their origin in the embryonic vessels that connect the cavernous portion of the developing internal carotid arteries (ICA) and the paired longitudinal neural arteries that will later form the basilar artery (BA) [1, 2]. While the trigeminal artery usually involutes after the development of the posterior communicating artery (PcoA) there are cases, for reasons still unclear, where it remains persistent . The PTA is the most common persistent embryonic carotid–basilar anastomosis . Prevalence varies from 0.12 to 1% in studies using magnetic resonance angiography imaging or classical angiography [3,4,5,6,7,8]. In this paper we will briefly explain what is a PTA and to what pathologies it can be associated, we will review the meaning of a PTA in a posterior circulation stroke through a clinical case and we will present a table that summarizes the PTA related strokes reported in literature.
The different variations of the PTA can be cataloged using the Saltzman classification (Fig. 1), [1, 9, 10]. In Saltzman type 1, also called fetal PTA, the PTA insertion in the BA is distal to the anterior inferior cerebellar artery (AICA) and proximal to the superior cerebellar artery (SCA) and, in some cases, the BA proximal to the insertion of the PTA may be hypoplastic and the PcoA of the same side may be absent. In the Saltzman type 2 there is usually no hypoplasia of the BA, the PTA inserts proximally to the SCA, supplying them, and the PCAs are predominantly supplied by the PcoA. In the Saltzman type 3 variant, the PTA inserts directly into one of the cerebellar arteries, without having an anastomosis with the BA. In the case of Slatzman type 3 there are 3 variants: the type 3a variant that terminates in SCA; the type 3b variant, and the the most common one, that terminates into AICA; and type 3c variant that terminates into posterior inferior cerebellar artery (PICA) [1, 2]. In one study of 4.650 patients that underwent brain MRA, the prevalence of each type using the Saltzman classification was as follows: type I, 24%; type II, 16%; type III, 60% .
The PTA is linked to several pathologies, including vascular nerve compression syndromes, like trigeminal neuralgia (more prevalent in patients with PTA) [11, 12] or ophthalmoplegia due to oculomotor or abducens palsy [12,13,14]. It is also linked to hypopituitarism due to compression of the pituitary stalk [14, 15], spontaneous or traumatic intracavernous fistula  and brain aneurysms. Although there is no agreement that brain aneurysms are more prevalent in patients with PTA [4, 7, 17], the PTA itself is prone to aneurysms due to its bifurcation . Finally, the PTA is also related to ischemic stroke, although, to our knowledge it has never been linked to TIA by vertebrobasilar insufficiency [18,19,20,21,22,23,24,25,26,27,28,29,30]. We present in Table 1 a structured summary of the PTA related stroke cases reported in literature.
An 82-year-old man, presented to the emergency department, on February 2018, after sudden onset of left hemiparesis and vertigo. Symptoms started during a period of greater physical effort, upon participation in a zumba class. His past medical history included transient episodes of vertigo during exercise in the previous months, an anterior circulation right hemispheric stroke in 2015, that left no sequels, and hypertension controlled with a combination of 10 mg lisinopril and 2.5 mg amlodipine. The neurologic examination revealed mild left hemiparesis with facial involvement and crural predominance, vertical nystagmus, right internuclear ophthalmoplegia, dysarthria and dysmetria on the left arm. The total National Institutes of Health Stroke Scale (NIHSS) score was 6.
The plain brain CT scan was normal and a CT angiography showed hypoplasia of both vertebral arteries, the left terminating as the PICA, while the right gave origin to the BA. The BA had a filiform aspect in its proximal two thirds, having a normal caliber in the distal remaining third, after receiving a communicating artery from the cavernous segment of the left internal carotid artery, a PTA (Fig. 2). No abrupt stop of flow was identified. Echocardiogram showed severe dilation of the left auricle, as well as mild dilation of the right auricle and a 35 mm dilation of the proximal portion of the ascending aorta. Electrocardiogram was normal and a 48 h cardiac telemetry monitoring didn’t show any periods of arrhythmia. Lipid profile showed borderline high low density lipoprotein level, at 139 mg/dL.
The patient underwent treatment with recombinant tissue plasminogen activator (rt-PA) at two hours of symptom onset, this decision was based on the clinical presentation and in the absence of hemorrhage in the CT scan. Shortly after treatment the NIHSS score was 2, maintaining a slight paresis of the left leg and dysmetria on the left arm. Months later, the patient showed no neurologic sequelae.
Discussion and conclusions
PTA can be associated with many different vascular events. Patients with PTA and vertebrobasilar hypoplasia have a tendency to have a decreased vascular supply to the posterior fossa , this fact renders them susceptible to ischemic events. In this context, in the case of a stenosed carotid artery, a steal phenomenon can occur, and this can lead either to vertebrobasilar insufficiency or hemodynamic brain stem infarction . In the case of BA occlusion however, if the occlusion is proximal to the insertion of the PTA, the PTA can have a protective effect in the distal territory . In the case of an anterior circulation thrombus, the PTA can lead to migration of the thrombus to the BA, possibly causing a posterior circulation stroke [20, 24]. Finally, in BA hypoplasia, PTA also opens the possibility for thrombectomy in the posterior circulation [26, 27].
Despite all the variety of ischemic events related with PTA, thrombosis of this vessel remains a rare phenomenon, although there is a case report of PTA thrombosis related with internal carotid dissection .
Our patient had a congenital Saltzman type 1 PTA variant and presented with symptoms suggestive of acute brainstem infarction that partially resolved after the administration of rt-PA. The clinical manifestations are compatible with an ischemic lesion of the basis pons, causing an ataxic hemiparesis syndrome, and extending to the tegmental region, affecting the longitudinal medial fasciculus. This suggests that the most affected territory was dependent from the small perforating vessels of the BA. Furthermore, the patient was exposed to extenuating exercise when the symptoms started, this favors the possibility that the event was due to a steal phenomenon, but the fact that the patient had no great artery disease and the fact that the patient improved after rt-PA suggests that the mechanism could also have been thromboembolic. Upon literature review both mechanisms seem possible. We would also like to emphasize that the reported episodes of vertigo probably corresponded to previous transient ischemic attacks (TIA) in the same area, possibly being the first sign of vertebrobasilar insufficiency. To our knowledge this is the first case study to point out the possibility of having several transient episodes (in this case of vertigo) compatible with vertebrobasilar insufficiency as a premonitory sign of PTA related stroke.
Availability of data and materials
Anterior inferior cerebellar artery
Internal carotid artery
National Institutes of Health Stroke Scale PcoA - posterior communicating artery
Persistent trigeminal artery
Recombinant tissue plasminogen activator
Superior cerebellar artery
Trasient ischemic attacks
Meckel S, Spittau B, McAuliffe W. The persistent trigeminal artery: development, imaging anatomy, variants, and associated vascular pathologies. Neuroradiology. 2013;55(1):5–16.
Azab W, Delashaw J, Mohammed M. Persistent primitive trigeminal artery: a review. Turk Neurosurg. 2012;22(4):399–406.
Uchino A, Kato A, Takase Y, Kudo S. Persistent trigeminal artery variants detected by MR angiography. Eur Radiol. 2000;10(11):1801–4.
O'Uchi E, O'Uchi T. Persistent primitive trigeminal arteries (PTA) and its variant (PTAV): analysis of 103 cases detected in 16,415 cases of MRA over 3 years. Neuroradiology. 2010;52(12):1111–9.
Uchino A, Saito N, Okada Y, Kozawa E, Mizukoshi W, Inoue K, et al. Persistent trigeminal artery and its variants on MR angiography. Surg Radiol Anat. 2012;34(3):271–6.
Allen JW, Alastra AJ, Nelson PK. Proximal intracranial internal carotid artery branches: prevalence and importance for balloon occlusion test. J Neurosurg. 2005;102(1):45–52.
Chen YC, Li MH, Chen SW, Hu DJ, Qiao RH. Incidental findings of persistent primitive trigeminal artery on 3-dimensional time-of-flight magnetic resonance angiography at 3.0 T: an analysis of 25 cases. J Neuroimaging. 2011;21(2):152–8.
Rhee SJ, Kim MS, Lee CH, Lee GJ. Persistent trigeminal artery variant detected by conventional angiography and magnetic resonance angiography-incidence and clinical significance. J Korean Neurosurg Soc. 2007;42(6):446–9.
McKenzie JD, Dean BL, Flom RA. Trigeminal-cavernous fistula: Saltzman anatomy revisited. AJNR Am J Neuroradiol. 1996;17(2):280–2.
Saltzman GF. Patent primitive trigeminal artery studied by cerebral angiography. Acta Radiol. 1959;51(5):329–36.
de Bondt BJ, Stokroos R, Casselman J. Persistent trigeminal artery associated with trigeminal neuralgia: hypothesis of neurovascular compression. Neuroradiology. 2007;49(1):23–6.
Clerici AM, Merlo P, Rognone F, Noce M, Rognone E, Bono G. Persistent trigeminal artery causing "double" neurovascular conflict. Headache. 2009;49(3):472–6.
Olivares J, Alonso-Verdegay G. Persistent trigeminal artery and isolated sixth cranial nerve. Rev Neurol. 2007;44(11):685–6.
Tungaria A, Kumar V, Garg P, Jaiswal AK, Behari S. Giant, thrombosed, sellar-suprasellar internal carotid artery aneurysm with persistent, primitive trigeminal artery causing hypopituitarism. Acta Neurochir. 2011;153(5):1129–33.
Ekinci G, Baltacioglu F, Kilic T, Cimsit C, Akpinar I, Pamir N, et al. A rare cause of hyperprolactinemia: persistent trigeminal artery with stalk-section effect. Eur Radiol. 2001;11(4):648–50.
Tokunaga K, Sugiu K, Kameda M, Sakai K, Terasaka K, Higashi T, et al. Persistent primitive trigeminal artery-cavernous sinus fistula with intracerebral hemorrhage: endovascular treatment using detachable coils in a transarterial double-catheter technique. Case report and review of the literature. J Neurosurg. 2004;101(4):697–9.
Cloft HJ, Razack N, Kallmes DF. Prevalence of cerebral aneurysms in patients with persistent primitive trigeminal artery. J Neurosurg. 1999;90(5):865–7.
Iancu D, Anxionnat R, Bracard S. Brainstem infarction in a patient with internal carotid dissection and persistent trigeminal artery: a case report. BMC Med Imaging. 2010;10:14.
Momma F, Ohara S, Ohyama T. Persistent trigeminal artery associated with brainstem infarct--case report. Neurol Med Chir (Tokyo). 1992;32(5):289–91.
Schwartz NE, Albers GW. Neurological picture. Acute strokes in the setting of a persistent primitive trigeminal artery. J Neurol Neurosurg Psychiatry. 2007;78(7):745.
Suzuki S, Chang GY. A case of primitive trigeminal artery infarction. Neurology. 2010;75(18 Suppl 1):S66.
Gaughen JR, Starke RM, Durst CR, Evans AJ, Jensen ME. Persistent trigeminal artery: in situ thrombosis and associated perforating vessel infarction. J Clin Neurosci. 2014;21(6):1075–7.
Miller EC, Willey JZ. Bilateral occipital strokes from an atherosclerotic trigeminal artery. Neurology. 2016;86(5):489–90.
Foerch C, Berkefeld J, Halbsguth A, Ziemann U, Neumann-Haefelin T. Brain stem infarction caused by proximal internal carotid artery stenosis in a patient with a persisting primitive trigeminal artery. Cerebrovasc Dis. 2006;22(2–3):200–2.
Ito Y, Watanabe H, Niwa H, Hakusui S, Ando T, Yasuda T, et al. The protective effect of a persistent trigeminal artery on brain stem infarctions: a follow-up case report. Intern Med. 1998;37(3):334–7.
Imahori T, Fujita A, Hosoda K, Kohmura E. Acute ischemic stroke involving both anterior and posterior circulation treated by endovascular revascularization for acute basilar artery occlusion via persistent primitive trigeminal artery. J Korean Neurosurg Soc. 2016;59(4):400–4.
Mulder M, Lycklama ANGJ, Dinkelaar W, de Rooij T, van Es A, van der Kallen BF, et al. Thrombectomy in posterior circulation stroke through persistent primitive trigeminal artery: a case report. Interv Neuroradiol. 2015;21(6):715–8.
Kwon JY, Lee EJ, Kim JS. Brainstem infarction secondary to persistent trigeminal artery occlusion: successful treatment with intravenous rt-PA. Eur Neurol. 2010;64(5):311.
Yin S, Zhang HT, Zhang DP, Zhang SL. Persistent primitive trigeminal artery associated with monocular blindness and external carotid-vertebral artery anastomosis. Saudi Med J. 2015;36(5):626–9.
Parthasarathy R, Derksen C, Saqqur M, Khan K. Isolated intermittent vertigo: a presenting feature of persistent trigeminal artery. J Neurosci Rural Pract. 2016;7(1):161–3.
Palmer S, Gucer G. Vertebrobasilar insufficiency from carotid disease associated with a trigeminal artery. Neurosurgery. 1981;8(4):458–61.
No funding was obtained for this article.
Ethics approval and consent to participate
Consent for publication
The principal author has received the consent form from the patient concerned in the case we report to publish his clinical data, we have the consent form in file in case it is requested by the editor.
No competing interests to be declared.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Ferreira, A., Coelho, P.S. & Cruz, V.T. Persistent trigeminal artery in a patient with posterior circulation stroke treated with rt-PA: case report. BMC Neurol 19, 257 (2019). https://doi.org/10.1186/s12883-019-1492-2
- Posterior trigeminal artery
- Vertebrobasilar insufficiency
- Saltzman classification
- CT angiography