Abstract
Purpose: :
To develop method of objective estimation of the Add value (AV) for PG in myopic children.
Methods: :
56 children, 8-17 years old, with myopia from -0.5D to -7.0D, myopic progression of 0.25-1.5D/year, binocular vision, decreased binocular accommodation response (BAR) and reserved relative accommodation (RRA), were randomly assigned as follows: Group I (32 children) had the AV estimated upon their RRA: AV was +0.75D to +1.25D when RRA was above 1.5D, and +1.5D to +2.0D when RRA was under 1.5D; Group II (24 children) had their AV estimated as follows: lenses 0.25-0.5D below actual cycloplegic refraction at 5m-distance were used, ensuring resulted visual acuity not lower than 20/25. Then convex lenses were gradually added until the dynamic refraction with the lens for 33cm, 2.5D, was reached, as in normal OAR. Power of the obtained convex lens was used as an optimal AV.
Results: :
Baseline (Mean±St.Err.) non-cycloplegic refraction (NCR) was -3.61±0.28D, and cycloplegic refraction (CR) was -3.34±0.28D in Group I, and, respectively, -3.67±0.25D and -3.24±0.27D, in Group II. In 6 months of using PG, the NCR was -3.79±0.32D in Group I, and -3.65±0.26D in Group II. In 12 months, it was -4.06±0.25D in Group I, and -3.92±0.3D in Group II (p>0.05). CR after 6 months of using PG remained the same. In 12 months, it was -3.79±0.19D in Group I, and -3.49±0.18D (p<0.05). Progression of myopia in 12-month period was 0.45D in Group I, and 0.25D in Group II (p0.05), while in Group II it remained the same. Baseline RRA was 1.43±0.21D in Group I, and 1.6±0.22D in Group II. In 6 months of using PG, it increased by 0.43±0.29D in Group I, and by 0.47±0.28D in Group II (p>0.05). In 12-months, RRA in Group I has decreased by 0.37D, returning to the baseline level, while in Group II, it has decreased by 0.2D, exceeding the baseline by 0.27±0.22D (p<0.05).
Conclusions: :
Our method of estimating the AV for PG in children with myopia and accommodation insufficiency allowed to slowing down the progression of myopia.
Keywords: myopia • accommodation • refraction