Atrofia cortical posterior

Abstract

Posterior cortical atrophy (PCA) is a dementing syndrome characterized by an early alteration of higher visual functions. Patients usually develop a perceptive visual agnosia related to Balint syndrome. Verification showed Alzheimer s disease (AD) in most PCA observations (13/14 cases), and it can be concluded that there is a posterior variant of AD with prominent visual symptomatology. However, most PCA cases have not been verified and the nature of the disorder remains unknown in these observations. An early and severe unilateral occipital horn dilatation was found in one out of every six cases with non verified PCA. To the best of our knowledge, this image has not been described in AD and these observations could be of different nature. On the other hand, some non verified PCA cases have occasionally manifested as an associative visual agnosia. The nature of this type of associative disorder is unknown, but it could be similar to the nature of semantic dementia, a non Alzheimer s syndrome related to unspecific lesions of temporal lobes.