Bilateral Thalamic Ischemic Stroke Secondary to Occlusion of the Artery of Percheron

Abstract

The occlusion of the artery of Percheron (AOP) is a rare condition that causes bilateral thalamic ischemic stroke with or without midbrain involvement. It happens as a result of an anatomical variant of the diencephalic irrigation, in which the thalamic paramedian arteries arise from a common trunk from the posterior cerebral artery (PCA), which generates a clinical syndrome characterized by bilateral vertical gaze palsy, memory impairment and hypersomnia. In this case, we report a 62-year-old woman admitted to the emergency room with altered mental status, mainly somnolence. On physical examination, she was somnolent, apathetic and with no motor deficit. Magnetic resonance imaging (MRI) of the brain demonstrated bilateral thalamic hyperintensities and midbrain involvement in diffusion-weighted imaging (DWI) and T2 sequences, suggesting occlusion of the AOP. Bilateral thalamic infarction due to this anatomical variant is an entity with a low prevalence, and its diagnosis can be delayed because of the wide spectrum of clinical signs.

Artery of Percheron Stroke as an Unusual Cause of Hypersomnia: A Case Series and a Short Literature Review

“…The prevalence of bilateral thalamic infarction caused by AOP occlusion is unknown since it is often misdiagnosed (Arauz et al, 2014). It "seems" that AOP stroke represents 0.1% to 2.0% of ischemic strokes and 4% to 18% of thalamic infarcts (Agarwal et al, 2014;Caruso et al, 2017;Garcia-Grimshaw et al, 2018;Lamot et al, 2015). There is no predilection as regards sex, race-ethnicity, and age in the reported cases of AOP stroke in literature.…”

“…The risk factors of AOP stroke are similar to those of ischemic ones. The two most frequent risk factors are microangiopathy and cardiac embolism (Arauz et al, 2014;Garcia-Grimshaw et al, 2018). The clinical presentations of AOP stroke are extremely variable.…”

“…The clinical presentations of AOP stroke are extremely variable. The most common clinical features are bilateral vertical gaze palsy (65%), memory impairment (anterograde and retrograde amnesia) (58%), and coma (42%; Garcia-Grimshaw et al, 2018;Lamboley et al, 2011;Lamot et al, 2015). The remaining clinical features reported in the literature include hypersomnolence (29%), akinetic mutism, and behavioral disorders (apathy, agitation, and aggressiveness; Agarwal et al, 2014;Caruso et al, 2017;Garcia-Grimshaw et al, 2018;Lamboley et al, 2011;Lamot et al, 2015;Lazzaro et al, 2010).…”

Sequential Thalamic Hemorrhage and Ischaemia in the Percheron Artery Territory

“…Bilateral thalamic ischemic vascular lesions have been reported as 0.6% of all infarctions [5]. Bilateral ischemia may occur because the artery of Percheron supplies the paramedian nuclei bilaterally in up to 12% of individuals [1,2,9]. At times, the anterior thalamic nuclei, usually supplied by the polar artery arising from the posterior communicating artery on each side, may receive their vascular supply from the Percheron artery or from a single polar artery explaining bilateral anterior paramedian infarctions [3].…”

Bilateral thalamic infarction secondary to artery of Percheron occlusion: A rare cause of acute coma

“…[1] It is approximated that strokes involving the AOP account for only 0.1%-2% of all ischemic strokes, but the anatomic variant is estimated to be present in 4%-11% of the general population. [2,3] Clinical features such as variable levels of consciousness, vertical gaze palsy, oculomotor disturbances, hemiplegia, cerebellar ataxia, and movement disorders have all been described. [2] The clinical features of this stroke are very complex and the presentation variability often leads to a delay in diagnosis with a large differential diagnosis.…”