Artery of Percheron infarction: A rare case with prolonged disturbance of consciousness

Introduction: The artery of Percheron (AOP) is a rare anatomical variant in which both paramedian thalami are supplied by a single perforating artery. Occlusion of this artery causes bilateral thalamic infarction. The clinical picture most often typically presents with consists of the disturbance of consciousness, hypersomnolence, vertical gaze limitation, oculomotor disturbances, and memory impairment. However, because it is rare and early findings are nonspecific, diagnosis can be delayed. This report presents a patient who presented with prolonged disturbance of consciousness and was diagnosed with AOP infarction.Case: A 58-year-old woman who developed disturbance of consciousness after a headache was evaluated with neurological examination, laboratory tests, cranial imaging, and an etiological work-up. Her clinical course was followed during hospitalization. Cardiology, internal medicine, and physical therapy consultations were obtained for the etiology. Treatment included antiplatelet and anticoagulant therapy, enteral nutrition, fluid-electrolyte support, and neurostimulant treatments for the arousal disorder. Her history included diabetes mellitus and hypertension. On neurological examination in the emergency department, she was stuporous, responded only minimally to painful stimuli, and had no light reflex bilaterally. No obvious lateralizing neurological deficit was found. Diffusion-weighted cranial magnetic resonance imaging showed diffusion restriction consistent with acute infarction in both thalami (Figure 1). MR angiography showed an artery of Percheron variant, a single trunk supplying the bilateral paramedian thalamic perforating arteries (Figure 2). CT angiography showed a filling defect consistent with thrombus in the V4 segment of the left vertebral artery. Left ventricular systolic dysfunction on cardiac evaluation supported a cardioembolic etiology. During follow-up her level of consciousness improved gradually under amantadine and then modafinil. She was transferred to the ward at about the third week, and at the third-month follow-up she had largely returned to activities of daily living, with only mild right hemiparesis and vertical gaze limitation persisting.Discussion/Conclusion: AOP infarction should always be considered in the differential diagnosis when unexplained disturbance of consciousness and bilateral thalamic lesions are present. Early neuroimaging, appropriate medical treatment, and a multidisciplinary approach can support clinical recovery. This case shows that meaningful functional improvement can be achieved with appropriate treatment and close follow-up.Keywords: