QUANTIFICATION OF CORTICAL ATROPHY IN A CASE OF PROGRESSIVE FLUENT APHASIA

A patient with a rapidly developing fluent progressive aphasia was tes ted prospectively up to the time of death and examined neuropathologic ally. Severe impairment in accessing semantic skills with substantiall y intact phonological, syntactic and discourse skills was found. Some social behavioural difficulties were also noted. This case presented a unique opportunity to relate this significant language impairment to the pattern of neurodegeneration, a difficult task in most neuropathol ogical studies of severe end-stage dementia. A detailed neuropathologi cal examination revealed focal atrophy with neuronal loss without neur onal inclusions (Pick bodies, Lewy bodies, neurofibrillary tangles or senile plaques) or neuronal changes (shrinkage or swelling). In additi on, spongiform degeneration (confined to layer two of the cortex) and gliosis were detected at atrophic sites. To establish the amount of ti ssue loss and pathology associated with the focal language deficit, vo lume analyses were performed and compared with two age- and sex-matche d, neurologically normal controls. Both the left and right angular gyr i and Brodmann's area 37 showed marked volume reduction compared with controls. The predominant language impairment seen in this case is lik ely to reflect these marked changes in the posterior parieto-temporal areas. The milder unilateral atrophy was concentrated in the right tem poral lobe as well as the right hemisphere homologue of Broca's area. Recent work suggests a relationship between such unilateral changes an d the social behavioural difficulties which were noted in this case. T he hippocampus and other gyri such as the supramarginal gyrus showed n o volume loss compared with controls correlating with the relative pre servation of other language skills.