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Published on: June 14, 2021
Cyclic exotropia associated with retinitis pigmentosa
1Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, 300 Gumi-dong, Bundang-gu, Seongnam, Gyeonggi-do, 463-707, South Korea. hjm@snu.ac.kr
Summary
Cyclic exotropia, a condition causing outward eye turning, was observed in a patient with retinitis pigmentosa. This previously unreported association highlights a potential link between these two distinct ophthalmic conditions.
Area of Science:
- Ophthalmology
- Neuro-ophthalmology
- Genetics
Background:
- Retinitis pigmentosa is a group of inherited disorders characterized by progressive retinal degeneration.
- Cyclic exotropia is an intermittent outward deviation of the eye that typically recurs at regular intervals.
Observation:
- A 31-year-old male patient presented with a 4-year history of left-sided cyclic exotropia, alternating every 24 hours.
- Ophthalmologic examination revealed a comitant left exotropia of 30 prism diopters at distance and 25 prism diopters at near during the exotropic phase.
- Fundoscopy showed characteristic bone spicule formation and arteriolar narrowing, indicative of retinitis pigmentosa, with electroretinography demonstrating absent responses in both eyes.
Findings:
- The patient exhibited a 48-hour cycle for his exotropia.
- Diagnostic tests confirmed retinitis pigmentosa, including visual field testing showing a central island in both eyes.
Implications:
- This case suggests a potential, previously unreported association between cyclic exotropia and retinitis pigmentosa.
- Further research is warranted to explore the underlying mechanisms and prevalence of this association.
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