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Lid retraction in myasthenia gravis
Journal of Clinical Neuro-Ophthalmology
|September 1, 1987
Summary
Paradoxical upper lid retraction occurred in some myasthenia gravis patients, challenging Hering's law. Cholinergic overstimulation may explain this rare sign during treatment and after thymectomy.
Area of Science:
- Neurology
- Ophthalmology
Background:
- Myasthenia gravis is an autoimmune disorder affecting neuromuscular junctions.
- Ocular manifestations, including ptosis and lid retraction, are common in myasthenia gravis.
Purpose of the Study:
- To investigate the occurrence and potential mechanisms of paradoxical upper lid retraction in myasthenia gravis patients.
Main Methods:
- Retrospective analysis of 150 myasthenia gravis patients.
- Clinical observation of ocular signs, including lid position.
- Correlation with treatment modalities and thymectomy.
Main Results:
- Four out of 150 patients (2.7%) exhibited upper lid retraction.
- Two patients presented with contralateral ptosis.
- Three patients developed paradoxical lid retraction during medical treatment or post-thymectomy.
Conclusions:
- Paradoxical upper lid retraction is a rare finding in myasthenia gravis.
- Hering's law of equal innervation may not fully explain this phenomenon.
- Cholinergic overstimulation is proposed as a potential contributing factor to neuromuscular transmission alterations.
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