Persistent trigeminal artery causing "double" neurovascular conflict

Persistent trigeminal artery in a patient with posterior circulation stroke treated with rt-PA: case report

BACKGROUND

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.

CASE REPORT

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.

CONCLUSION

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.

Anatomical features and clinical relevance of a persistent trigeminal artery

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.

De-novo headache with transient vertebro-basilar symptoms: role of embryonic hypoglossal artery

We report the case of a 56-year-old man with acute onset of de-novo stabbing, pulsating and diffuse headache with subsequent appearance (within few minutes) of posterior fossa symptoms (vomiting, postural instability, anisocoria, incoordination, dysarthria, retropulsion) lasting 9–12 h. Recurrent hypertensive crises were detected during the acute observation in the Emergency Room, even in the absence of previous history of hypertension. Once subarachnoid hemorrhage and focal lesions (vascular and non-vascular) were excluded, brain computerized tomography-angiography and digital subtraction angiography disclosed the presence of left persistent primitive hypoglossal artery with bilateral vertebral artery hypoplasia and a slight aneurysmal dilation of the anterior communicating artery. Brain magnetic resonance study performed 24 h after onset of symptoms was negative for recent ischemic lesions. The clinical features of this rare vascular condition are discussed as a possible cause of magnetic resonance (diffusion weighted imaging) negative vertebro-basilar transient ischemic attack.