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Oculocardiac reflex caused by contact lenses.
Tatsuya Mimura1, Shiro Amano, Hideharu Funatsu
1Department of Ophthalmology, University of Tokyo Graduate School of Medicine, Tokyo, Japan. mimura@mbg.sphere.ne.jp
Summary
Contact lens insertion can rarely trigger the oculocardiac reflex, causing temporary unconsciousness. This reflex involves a drop in heart rate due to eye stimulation.
Area of Science:
- Ophthalmology
- Neurology
- Physiology
Background:
- The oculocardiac reflex is a well-documented phenomenon, typically associated with surgical procedures involving eye manipulation.
- It involves a decrease in heart rate and blood pressure due to stimulation of the trigeminal nerve in the eye.
Observation:
- Two cases are presented where patients experienced syncope (unconsciousness) immediately upon insertion of hard contact lenses.
- Both patients were young males, new to contact lens wear, and experienced decreased blood pressure during the episodes.
- Recovery was spontaneous within 10 minutes, followed by nausea and vomiting.
Findings:
- The forceful insertion or compression of the eye during contact lens fitting can elicit a significant oculocardiac reflex.
- This reflex, characterized by bradycardia and hypotension, can lead to transient loss of consciousness.
Implications:
- Ophthalmologists and opticians should be aware of this rare but potential complication during contact lens fitting.
- Careful insertion techniques, avoiding excessive eye compression, are crucial to prevent triggering the oculocardiac reflex in susceptible individuals.