The top of the basilar artery syndrome is a stroke syndrome involving the posterior circulation.
Location of occlusion: distal portion of the basilar artery where it branches into the posterior cerebral arteries. There may be bilateral thalamic ischemia due to occlusion of perforator vessels.
Risk factors:
(1) risk for stroke (hypertension, diabetes, obesity, etc)
(2) excessive alcohol intake
(3) cardiogenic thromboemboli
(4) hypercoagulable state
Clinical findings may include:
(1) oculomotor deficits
(2) pupillary abnormalities
(3) behavioral abnormalities
(4) variable unconsciousness
(5) variable quadriplegia
(7) variable incontinence
Diagnosis is made by MR angiography.
Reperfusion therapy is associated with improved outcomes.
Risk factors for a poor outcome:
(1) bilateral ocular palsy
(2) poor collateral circulation through the posterior communicating artery
