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Midbrain Infarction Resulting in Bilateral Pseudoabducens Palsies
Bonnie M Kaas1, David S Zee, Amir Kheradmand
1Departments of *Neurology †Ophthalmology ‡Otolaryngology-Head and Neck Surgery §Neurosurgery, Johns Hopkins School of Medicine, Baltimore, MD.
The Neurologist
|May 5, 2017
Summary
Pseudoabducens palsy, a rare eye movement disorder, is often caused by midbrain lesions. This case highlights its potential as a localizing sign in neurology.
Area of Science:
- Neuro-ophthalmology
- Neurology
Background:
- Pseudoabducens palsy is defined as abduction paresis without pontine or peripheral nerve lesions.
- It has been associated with mesodiencephalic lesions and may share mechanisms with thalamic esotropia.
Observation:
- A 55-year-old male presented with severe ophthalmoparesis, with only left eye adduction preserved.
- Brain MRI revealed a midbrain infarction as the cause.
Findings:
- Midbrain infarction can manifest as pseudoabducens palsy.
- This condition may be underdiagnosed but is a valuable localizing sign.
Implications:
- Identifying pseudoabducens palsy can aid in diagnosing specific neurological conditions.
- Understanding its pathophysiology is crucial for accurate diagnosis and treatment.
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