Photodiagnosis and Photodynamic Therapy
Chromatic-filter light therapy versus part-time occlusion for unilateral amblyopia: a quasi-experimental longitudinal study
By Shakila Abbas, Humaima Saeed and Memoona Arshad.
Abstract
Purpose
To compare wavelength-specific chromatic-filter light therapy using amber-red, yellow, or orange filters with conventional patching for unilateral amblyopia and to evaluate longitudinal changes in best-corrected visual acuity (BCVA), contrast sensitivity, and stereopsis.
Methods
This assessor-masked, quasi-experimental study included 88 participants aged 5–15 years with unilateral anisometropic or strabismic amblyopia after refractive adaptation. Forty-six participants received chromatic light therapy and 42 received part-time patching. The chromatic group included amber-red (n = 16), yellow (n = 15), and orange (n = 15) subgroups. Outcomes were assessed at 4 weeks, 3 months, 5 months, 7 months, and 2 months after treatment cessation. Baseline-adjusted linear mixed-effects models were fitted using restricted maximum likelihood and an autoregressive AR(1) covariance structure. Fixed effects included follow-up visit, treatment group, the visit-by-treatment interaction, and the corresponding baseline outcome.