Top of the Basilar Syndrome With Disturbed Consciousness

A 73-year-old man presented with a history of hypertension and paroxysmal atrial fibrillation for which he was undergoing treatment. One day, he experienced disturbance in consciousness after dinner and was brought to our hospital by ambulance. His body temperature was 35.1°C. He had a regular heart rate of 63 beats/min, blood pressure of 121/95 mm Hg, and disturbed consciousness (E1V2M5); however, his consciousness returned after the insertion of a ureteral catheter. No obvious abnormalities were observed in a neurological examination. Blood glucose and serum electrolyte levels, liver and kidney function test results, and cranial computed tomography revealed no abnormality. After being admitted to our hospital, his consciousness level was unstable and the tendency to somnolence persisted. Top of the basilar syndrome was diagnosed on the basis of cranial magnetic resonance imaging conducted a day after admission (Figure).1Pessin M.S. Gorelick P.B. Kwan E.S. Caplan L.R. Basilar artery stenosis: middle and distal segments.Neurology. 1987; 37: 1742-1746Crossref PubMed Google Scholar A repeated neurological examination revealed limited downward gaze in both the eyes. Heparin administration extended the time for which the patient could stay awake, and he was discharged 13 days after the onset of the illness. The main symptoms of top of the basilar syndrome are disturbances of consciousness, hypersomnia, and vertical gaze palsy, with quadriplegia being uncommon. Cranial magnetic resonance imaging seems to be useful for the differential diagnosis of persistent disturbance of consciousness in top of the basilar syndrome.2Hattingen E. Blasel S. Nichtweiss M. Zanella F.E. Weidauer S. MR imaging of midbrain pathologies.Clin Neuroradiol. 2010; 20: 81-97Crossref PubMed Scopus (12) Google Scholar