Abstract
Purpose:
To investigate the pattern of dynamic accommodative response of myopic eyes after orthokeratology.
Methods:
Ten myopic children (mean ± SD age: 10.1 ± 2.4 years) who fitted orthokeratology lenses in both eyes were recruited. The right eye of each subject was investigated before dispensing, and 1 month, 3 month and 6 month after Orthokeratology. For each visit, accommodative stimuli was given by a Badal system. Meanwhile, dynamic accommodation was continuously recorded using Grandseiko WAM-5500 auto-refractor. Real-time imaging of the anterior segment was simultaneously performed using a custom-built ultra-long scan depth OCT based on CMOS camera. The values of accommodative response (AR), as well as anterior chamber depth (ACD), pupil diameter (PD), lens thickness (LT), anterior (LAC) and posterior (LPC) surfaces curvatures of the lens were obtained. Then custom algorithms were developed to fit curves and to yield dynamic aspects (latency, peak velocity, and amplitude) for the changes of the above parameters.
Results:
The latency of AR decreased and the peak velocity of AR increased at 3 months and 6 month after orthokerotology compared to baseline (Re-ANOVA and post hoc test, P < 0.01). The amplitude of AR increased at 6 month after orthokerotology (P < 0.01). For non-accommodative condition, ACD, and the radii of ASC were found significantly decreased at 1 month, 3 month and 6 month after Orthokeratology compared to baseline (P < 0.01). Meanwhile, the LT was found significantly increased (P < 0.01).
Conclusions:
Dynamic accommodation was improved in myopic children after Orthokeratology. The morphology of anterior eye seemed to be more “accommodative” at relax status. This may suggest that the improvement of accommodation is a key factor for myopia control using Orthokeratology.