Related Experiment Videos
Eye elongation during accommodation in humans: differences between emmetropes and myopes
W Drexler1, O Findl, L Schmetterer
1Institute of Medical Physics, University of Vienna, Austria.
Investigative Ophthalmology & Visual Science
|October 7, 1998
Summary
Eye elongation occurs during accommodation, with greater changes observed in emmetropes than myopes. This finding advances understanding of myopia pathogenesis and eye growth mechanisms.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Physiology
Background:
- Myopia pathogenesis is debated, with exaggerated eye growth implicated.
- Near work correlates with refractive error, but axial length changes during accommodation are poorly understood.
- Current biometric techniques lack the precision to study these subtle eye length variations.
Purpose of the Study:
- To investigate axial eye length changes during accommodation using partial coherence interferometry (PCI).
- To compare accommodation-induced eye elongation in emmetropic and myopic eyes.
- To assess the precision of PCI for measuring dynamic eye length changes.
Main Methods:
- Employed partial coherence interferometry (PCI), a high-precision, noninvasive technique.
- Measured axial eye length changes in 11 emmetropic and 12 myopic eyes during monocular accommodation.
- Investigated interocular differences in eye elongation in 7 subjects.
Main Results:
- All eyes showed elongation during accommodation.
- Accommodation-induced eye elongation was significantly greater in emmetropes (12.7 microm) than myopes (5.2 microm).
- No significant differences in accommodative amplitude or interocular elongation were found.
Conclusions:
- Accommodation causes axial eye elongation, potentially due to ciliary muscle contraction affecting scleral circumference.
- PCI technology enables precise measurement of accommodation-induced eye length changes in humans.
- Findings contribute to understanding myopia development and eye growth dynamics.