Visual impairment and posterior cortical atrophy preceding rapid progressive dementia.

Posterior cortical atrophy (PCA), also known as Benson's disease, has been previously reported as a variant of Alzheimer's disease (AD). We present a clinical picture and MRI findings of a patient with PCA who developed early right-sided homonymous haemianopia and marked atrophy of parieto-occipital regions of the brain before a cognitive decline appeared. This case demonstrates that PCA may appear with advanced brain atrophy at the onset of focal visual deficits before the development of progressive dementia, and adds to the knowledge of dementias with rapid progression.