VISUOSPATIAL DYSGNOSIA AND BALINTS-SYNDROME AS MAJOR SYMPTOMS OF PROBABLE ALZHEIMERS-DISEASE

We describe three patients, respectively 57-, 54- and 55-years-old at onset of the disease, who developed over many years a progressive cort ical visual dysfunction without overt dementia. At onset, the visual s ymptoms were mainly a visuo spatial dysgnosia, but they progressively worsened to a near complete Balint syndrome in the three cases. In all of them, memory and language were only mildly affected during the fir st years of evolution, but a constructive and/or dressing apraxia and an optic ataxia in the left visual hemifield suggested in two cases a predominant dysfunction in the right hemisphere. Imaging of the brain by CT scan and MRI showed no focal atrophy, but the metabolic SPECT wa s early abnormal in all three cases showing a right posterior metaboli c defect in two cases and a bilateral posterior hypometabolism in one case. Follow-up of the patients showed that they all developed languag e and memory disturbances leading to severe dementia after 5-8 years o f evolution. It is suggested that these patients are affected by a vis ual form of Alzheimer's disease which is probably the most frequent ca use of progressive Balint-Holmes syndrome.