Lowering of the level of consciousness by bilateral paramedian thalamic infarction due to Percheron’s ischemia (Percheron’s syndrome): a case report

Context: Ischemia of Percheron’s artery(PA) is a rare neurological occurrence that results in bilateral paramedian thalamic infarction that may affect the midbrain. Among the symptoms are altered mental status, vertical ocular palsy, and memory changes, as well as hemiplegia, cerebellar ataxia, and movement disorders. Objective: To elucidate a case of stroke of the mesencephalic trunk in an uncommon anatomical variant of the thalamus-perfurans arteries Method:Daily neurological and laboratory evaluation in addition to complementary examinations such as skull CT and skull MRI. We also performed a qualitative analysis of articles in Portuguese and English journals indexed in the following databases: PubMed (Public Medical Literature Analysis), Lilacs (Latin American and Caribbean Literature on Health Sciences) and Scielo (Scientific Eletronic Library Online). Case report: A 67 year old male presented with mild to moderate headache for 2 days, reporting chronic cough and decreased level of consciousness for 1 day. He was intubated (Glasgow 6) and sedated for diagnostic elucidation. The CT shows mild cerebral edema and MRI shows bilateral thalamic infarction affecting the PA. The clinical picture evolves to ischemic stroke of the mesencephalic trunk. Discussion: The bilateral infarction of the Percheron artery, as presented in this case, the neurological and neuropsychological manifestations are more severe such as akinetic mutism, thalamic dementia and loss of self psychic activation(Robot Syndrome). In these cases, the neuropsychological disturbance is best noticed when the patient regains consciousness. Conclusion: In the presence of a clinical presentation suggestive of bilateral thalamic infarction, the Percheron Syndrome hypothesis should be suspected.