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Effects of General Anesthesia on Ocular Refraction
Manami Kawai1, Hitoshi Ishikawa1,2, Sonoko Tatsui1
1Department of Ophthalmology, School of Medicine, Kitasato University, Kanagawa, Japan.
Journal of Binocular Vision and Ocular Motility
|June 28, 2022
Summary
General anesthesia induced myopia in children undergoing strabismus surgery, evidenced by increased spherical and cylindrical eye power. This suggests autonomic nervous system changes during anesthesia affect ocular refraction.
Area of Science:
- Ophthalmology
- Anesthesiology
- Autonomic Nervous System
Background:
- General anesthesia is known to influence autonomic nervous system activity.
- Understanding its impact on ocular parameters is crucial for patient care.
Purpose of the Study:
- To investigate the effects of general anesthesia on objective ocular refraction in pediatric patients.
- To determine if general anesthesia induces changes in refractive error.
Main Methods:
- 57 patients (112 eyes) under 15 years undergoing strabismus surgery were studied.
- Objective refraction, corneal power, and pupil diameter were measured before and during general anesthesia using a handheld refractive keratometer.
- Data analysis included correlation and statistical significance testing.
Main Results:
- Spherical myopic power increased significantly from -0.75 D to -2.29 D.
- Cylindrical power also increased significantly from -0.90 D to -1.39 D.
- Corneal refractive power decreased by 0.25 D, and spherical power correlated negatively with age.
Conclusions:
- General anesthesia can induce myopia, as shown by objective refraction changes.
- Corneal flattening suggests ciliary muscle contraction, possibly due to parasympathetic dominance during anesthesia, is the primary cause.
- These findings highlight anesthesia-induced autonomic shifts impacting ocular refraction.
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