A rare case of ischemic stroke following occlusion of the artery of Percheron

A 57-year-old man was admitted to the ER after falling on the back of his head without any prodromi. No loss of consciousness was noted. The patient was responsive and able to walk into the ambulance without any help. Besides alcohol and nicotine abuse, medical history was blank. At ICU admission physical examination showed a patient with impaired consciousness, a Glasgow Coma Scale of 8 and distinct anisocoria with an unresponsive mydriatic left pupil. Vestibulo-ocular reflexes were preserved. The man had appropriate responses to nociceptive stimuli and normoflexia was seen with down going plantar reflexes with Babinski sign negative for both sides. Blood pressure was elevated but further cardiovascular, respiratory and abdominal examination was unremarkable. Apart from the elevated non-sober blood glucose level and hypercholesterolemia, all parameters ranged within normal limits. Chest X-ray depicted an enlarged heart shadow with bilateral perihilar vascular consolidation. Cerebral computed tomography (CT) (Fig. A) showed no obvious brain lesions. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the brain revealed T2-weighted hyperintense signals of the thalami and left mesencephalon (Fig. B), suggesting bilateral paramedian thalamic and left mesencephalic infarction. Diffusion weighted MRI also confirmed the suspected diffusion restriction in these regions (Fig. C), highly suggestive for an acute infarction in the artery of Percheron territory. Transcranial Doppler and 3D time-of-flight MR angiography (TOF-MRA) displayed lightgraded ostial occlusion of the internal carotid on both sides, without evidence for carotid or vertebral dissection. The patient’s condition improved gradually and after 12 days he was transferred for further revalidation. Both electrocardiogram and Holter monitoring demonstrated nothing abnormal. Echocardiography confirmed hypertrophy of the heart with a tricuspid insufficiency grade I and the patient was diagnosed with a hypertensive hypertrophic cardiomyopathy. No evidence was found suggesting a possible extracranial cause for embolism. Antithrombotic and antihypertensive therapy was initiated at the time of admission, along with insulin to correct hyperglycemia, A statine was proposed because of the hypercholesterolemia. Cognitive revalidation was initiated after his transfer.