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Effect of iris show on perceived upper eyelid height
Jacob A Evans1, Thomas J E Clark2, Kai Wang3
1Carver College of Medicine, University of Iowa, Iowa City, IA.
Canadian Journal of Ophthalmology. Journal Canadien D'Ophtalmologie
|October 21, 2018
Summary
Visible iris show affects perceived eyelid height, particularly in lighter irises. Less iris show makes eyelids appear droopier, suggesting potential nonsurgical treatments for blepharoptosis.
Area of Science:
- Ophthalmology
- Perceptual Science
Background:
- Perception of upper eyelid height is crucial in diagnosing and treating conditions like blepharoptosis.
- The concept of "iris show" (visible iris tissue) has not been fully evaluated for its impact on perceived eyelid height.
Purpose of the Study:
- To introduce and define "iris show."
- To assess how iris show influences the perception of upper eyelid height.
- To explore nonsurgical treatment options for mild blepharoptosis.
Main Methods:
- A survey was administered to 390 participants using photographs with varying iris colors and pupil sizes but identical upper eyelid marginal reflex distance (MRD1).
- Participants identified the "droopier" eyelid or indicated if heights were the same.
- Statistical analyses included t-tests.
Main Results:
- In blue and green irises, reduced iris show was significantly associated with the perception of a more ptotic eyelid (p = 0.002 and 0.03).
- In dark brown irises, perceived eyelid height remained consistent despite variations in iris show (p = 0.002).
Conclusions:
- Reduced iris show leads to a perceived lowering of the upper eyelid in individuals with light-colored irises.
- This effect is less pronounced in darker irises.
- Topical apraclonidine may be a viable nonsurgical treatment for mild blepharoptosis, especially in light-eyed individuals, by increasing iris show and enhancing perceived eyelid elevation.
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