Affiliations: Department of Psychology, Milano-Bicocca University,
Milan, Italy | Vita-Salute University and San Raffaele Scientific
Institute, Milan, Italy | Department of Clinical Neurosciences, San Raffaele
Turro Hospital, Milan, Italy | Nuclear Medicine Unit and Division of Neuroscience,
San Raffaele Scientific Institute, Milan, Italy
Note: [] Corresponding author: Eleonora Catricalà, Vita-Salute
University and San Raffaele Scientific Institute, Milan, Italy.
E-mail: [email protected]
Abstract: Posterior cortical atrophy (PCA) is an uncommon presentation of
Alzheimer's disease (AD), characterised by prevalent anatomo-functional
involvement of posterior cortical areas. Accordingly, the main clinical
features at onset are disorders of high-order visual processing, such as alexia
and impairments of visuo-spatial and visuo-constructional abilities. The
clinical features in the early stages of disease are variable, and they have
been suggested to stem from prevalent ventral or dorsal brain pathology, and/or
asymmetric hemispheric involvement. With disease progression, these differences
tend to blur with the increasing severity of neuropsychological dysfunction. We
report two PCA patients showing different patterns of reading impairment
(respectively, letter-by-letter reading and neglect dyslexia). A follow-up
study suggested that the qualitative features of alexia remain distinctive with
disease evolution. In addition, single photon emission tomography (SPECT)
studies revealed different patterns of hypoperfusion, consistent with the
alexia types. A careful reading assessment can provide important insights to
the pattern of progression of the disease in patients with PCA up to the late
stages of the pathology.
