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Homonymous hemianopia in stroke.
Xiaojun Zhang1, Sachin Kedar, Michael J Lynn
1Departments of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, USA.
Summary
Ischemic stroke is the primary cause of homonymous hemianopia (HH), particularly from occipital lobe lesions. The visual field defect pattern does not reliably indicate the exact location of the brain lesion.
Area of Science:
- Neurology
- Ophthalmology
- Neuroscience
Background:
- Homonymous hemianopia (HH) is often attributed to occipital stroke.
- Previous studies lacked consistent brain imaging support for this association.
Purpose of the Study:
- To investigate the causes of homonymous hemianopia (HH).
- To compare clinical and visual field characteristics of stroke-related versus non-stroke-related HH.
Main Methods:
- Retrospective review of medical records (1989-2004) for patients with HH and brain imaging.
- Categorization of HH causes into stroke and non-stroke conditions.
- Comparison of clinical and visual field data between groups.
Main Results:
- Stroke accounted for 69.7% of 902 HH cases, with infarction being the most common type (84.4%).
- Non-stroke causes included head trauma, brain tumors, and multiple sclerosis.
- Occipital lesions were most frequently stroke-related; HH configuration did not predict lesion location.
Conclusions:
- Ischemic stroke is the leading cause of HH, often due to occipital lobe lesions.
- Occipital strokes causing HH typically present without other neurological symptoms.
- The specific pattern of homonymous hemianopia does not localize the retrochiasmal lesion.
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