Clinical features:
(1) severe hypertension
(2) visual disturbances associated with hypertensive retinopathy
(3) variable headache
(4) variable impairment in the level of consciousness, including confusion
(5) variable paresthesias and/or weakness and/or gait abnormalities
Imaging studies:
(1) swelling and diffuse hyperintense lesions in the brainstem and cerebellum on T2-weighted and/or FLAIR (fluid-attenuated inversion recovery) MRI
(2) absence of lesions in the parieto-occipital lobes
(3) variable involvement of the basal ganglia
Sometimes patients may have marked changes on the MRI yet few clinical symptoms (clinico-radiologic dissociation).
Many of the changes are reversible once the hypertension is brought under control, but residual damage may be present.
Differential diagnosis:
(1) tumor in the brainstem
(2) infarction of the brainstem and/or basal ganglia
(3) infection
(4) brainstem encephalopathy without hypertension.