CORTICAL BLINDNESS AND ANTON SYNDROME IN POSTERIOR CORTICAL ATROPHY

Abstract

The dementia disorder - Posterio Cortical Atrophy (PCA) is clinically characterized by progressive impairment in visuoperception and visuospatial function. The imaging studies (brain MRI and FDG-PET/CT) show outstanding cortical atrophy or hypometabolism of visual association cortices of occipital, temporal and parietal lobes. Though the underlying pathology includes Alzheimer's disease, corticobasal degeneration and Lewy-body dementia, Alzheimer's pathology has been reported in majority of PCA patients in medical literature. Among all visual symptoms of PCA, cortical blindness and Anton syndrome mostly devastate patients. In this report, the PCA patients with cortical blindness and Anton syndrome are studies in a dementia specialty clinic. The medical charts of patients, who had met the diagnostic criteria of PCA from July 2015 to December 2016, were reviewed. For this study, the patients with documented cortical blindness and Anton syndrome were recruited. The data of clinical evaluation, MMSE scores, brain MRI studies, neurological reports, FDG-PET/CT, Amyloid-PET/CT and neuropsychiatric profiles were analyzed. There were four PCA patients with cortical blindness and Anton syndrome (one woman; three men). The average age was 58. Compared with the PCA patients without cortical blindness and Anton syndrome, these four subjects displayed either worse cortical atrophy of brain MRI studies or severe hypometablism of the FDG-PET/CT study. However, the positive result of Amyloid PET/CT was the same in these four subjects as those patients without cortical atrophy and Anton syndrome. These four subjects presented frequent neuropsychiatric symptoms daily, including agitation and visual hallucinations. The progression of PCA often results in cortical blindness and Anton syndrome. The implication of this development is extensive neuron loss and breakdown of higher cortical visual system. Early intervention of the Alzheimer pathology could be the future hope to halt the progression of PCA.