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Published on: November 12, 2020
[Homonymous hemianopia and posterior cortical atrophy].
M Formaglio1, P Krolak-Salmon, C Tilikete
1Service de neurologie D, unité de neuro-ophtalmologie, hôpital neurologique Pierre-Wertheimer, hospices civils de Lyon, université Lyon-1, Bron, France. formaglio.maite@orange.fr
Revue Neurologique
|January 7, 2009
Summary
Posterior cortical atrophy (PCA) can cause homonymous hemianopia (HH), a visual field defect. Early detection of PCA is crucial for managing higher visual dysfunction and dementia progression.
Area of Science:
- Neuroscience
- Ophthalmology
- Neurology
Background:
- Posterior cortical atrophy (PCA) is characterized by visual dysfunction and posterior brain atrophy.
- Homonymous hemianopia (HH) is rarely documented in PCA.
Observation:
- Six patients with PCA and HH were studied over 1-5 years.
- Patients presented with visual disorders, confirmed as HH via perimetry.
- Brain imaging (MRI/CT) and SPECT scans were performed.
Findings:
- HH occurred in four patients with left-sided and two with right-sided defects.
- Associated symptoms included simultagnosia, alexia, and visual agnosia, worsening over time.
- All patients developed dementia; diagnoses included probable Alzheimer's disease and corticobasal degeneration.
- Radiology confirmed posterior atrophy and reduced blood flow correlating with HH side.
Implications:
- Cortical lesions in PCA can affect visual areas, causing HH.
- Increased recognition of HH in PCA may reveal higher prevalence.
- Insidious HH warrants investigation for PCA, including neuroimaging and neuropsychological testing.
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