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Published on: April 14, 2014
Homonymous visual field defects in patients without corresponding structural lesions on neuroimaging
P W Brazis1, A G Lee, N Graff-Radford
1Department of Neurology, Mayo Clinic-Jacksonville, Florida 32224, USA.
Summary
Homonymous visual field defects can have organic causes even with normal neuroimaging. Alternative diagnoses like Creutzfeldt-Jacob disease or ischemia should be considered in such cases.
Area of Science:
- Neuro-ophthalmology
- Neurology
Background:
- Homonymous visual field defects typically indicate structural lesions in the retrochiasmal visual pathways.
- Neuroimaging, such as MRI and CT scans, usually identifies these structural abnormalities.
Observation:
- Four patients presented with homonymous visual field defects but had no detectable lesions on MRI or CT scans.
- This presentation challenges the assumption that normal neuroimaging excludes organic causes.
Findings:
- Identified etiologies included the Heidenhain variant of Creutzfeldt-Jacob disease, degenerative dementia, subtle occipital ischemia (detected via PET scanning), and nonketotic hyperglycemia.
- These findings highlight diverse organic causes for visual field loss despite unremarkable conventional imaging.
Implications:
- Clinicians must consider a broader differential diagnosis for homonymous visual field defects when initial neuroimaging is normal.
- Awareness of these alternative organic etiologies is crucial for accurate diagnosis and patient management.
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