INFARCTION IN THE TERRITORY OF THE RIGHT CHOROIDAL ARTERY AND MINOR HEMISPHERE SYNDROME - CASE-REPORT AND BRAIN GLUCOSE-UTILIZATION STUDY

A 72 year-old right handed woman had a right sided anterior choroidal artery infarction. She presented the triad of hemiplegia, hemianaesthe sia, and homonymous hemianopsia, as well as complete non-determinant h emisphere syndrome that combined: disorientation for place and time, a nosognosia, hemiasomatognosia, left spatial neglect, constructional ap raxia and spatial fabulation concerning both the present time and the weeks that preceded the vascular event. Language and verbal memory wer e normal. Spatial memory could not be studied because of the severity of the neglect, The clinical course was poor: when tested one and a ha lfyear post-onset, the hemiplegia, the hemianaesthesia, and the hemian opsia as well as left spatial neglect remained severe. Vestibular calo ric stimulation, carried out with left ear cold water irrigation, resu lted In brief but clear-cut allevation of the spatial neglect. An MRI with both axial and coronal slices showed a right-sided infarct affect ing tile whole posterior limb of the internal capsule including the ge nu, the posterior part of the globus pallidus, the anterior third of t he cerebral pediwcle and the amygdala but sparing the thalamus and the corona radiata. This crescent-shaped lesion transected entirely the t halamo-cortical connection fibers which resulted in a <<thalamic exclu sion>>. The measurement of brain glucose utilisation with(18F)-Fluoro- 2-Deoxy-D-Glucose and positron emission tomography performed in the ch ronic phase (3 months post-onset) showed an exceptionally severe rind widespread hypometabolism of the right hemisphere, relative to the lef t hemisphere, which correlated with both the unusual, severe and protr acted non-dominant hemisphere syndrome. AN the brain regions on the ri ght side were hypometabolic relative to the left including the tempora l region (mostly medial temporal), the left cerebellar lobe, the front al lobe (mostly prefrontal region), the occipital region and the thala mus. The hypometabolism of the basal ganglia, the sensorimotor area an d the parietal cortex was less severe. This most uncommon clinical-met abolic presentation presumably reflects a global thalamo cortical disc onnection inducing a diffuse dysfunction of the whole hemisphere.