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Progressive visual agnosia with posterior cortical atrophy
M Mizuno1, G Sartori, D Liccione
1Clinical Neuropsychology Service, Faculty of Psychology, University of Padua, Italy.
Clinical Neurology and Neurosurgery
|May 1, 1996
Summary
Posterior cortical atrophy (PCA) can progress asymmetrically. Early visual agnosia in a PCA patient evolved from unilateral to bilateral parieto-occipital hypometabolism.
Area of Science:
- Neurology
- Neuroimaging
- Cognitive Neuroscience
Background:
- Posterior cortical atrophy (PCA) is a neurodegenerative syndrome primarily affecting visual processing.
- Early diagnosis of PCA is crucial for understanding disease progression and management.
Observation:
- A case study of a patient presenting with progressive visual agnosia, a key symptom of PCA.
- Initial neuroimaging (SPECT and MRI) revealed left unilateral parieto-occipital involvement.
Findings:
- A subsequent PET scan eight months later demonstrated bilateral parieto-occipital hypometabolism.
- The hypometabolism was more pronounced in the left hemisphere, indicating asymmetric disease progression.
Implications:
- This case suggests that PCA degeneration can initiate unilaterally and spread bilaterally.
- Understanding asymmetric progression in PCA may refine diagnostic criteria and therapeutic strategies.
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