A newly developed spectacle lens shows promise in reducing myopia in children, a study in the British Journal of Ophthalmology reports. Researchers from Hong Kong and Japan found kids who wore the specialty spectacle lens had a 52% reduced rate of myopia progression compared with children who wore a single-vision spectacle lens. Additionally, the two-year study found axial elongation was significantly reduced by 62% in those who wore the specialty lens.
The lenses use defocus-incorporated multiple segments (DIMS), which have a central optical zone for correcting refractive error surrounded by areas of myopic defocus that extend to the mid-periphery of the lens.
The double-masked randomized controlled trial included 160 Chinese children ages eight to 13 with myopia between -1D and -5D and astigmatism of 1.50D or less. Children were randomly assigned to the DIMS group (79 participants) or the single-vision spectacle lens group (81 participants). The DIMS lenses incorporated multiple segments with myopic defocus of +3.50D. Additionally, investigators measured refractive error (cycloplegic autorefraction) and axial length at six-month intervals.
The study reported the average myopic progressions over two years were between -0.41D and 0.06D in the DIMS group and between -0.85D and 0.08D in the single-vision lens group. Additionally, the mean axial elongation was between 0.21mm and 0.02mm and 0.55mm and 0.02mm in the DIMS and single-vision groups, respectively. Also of note: 21.5% of the children who wore DIMS lenses had no myopia progression over two years compared with only 7.4% in the single lens group.
The DIMS spectacle lenses offer an alternative treatment modality for myopia control and are simple to use and the least invasive method compared with pharmacological or contact lens treatments, researchers said.
|Lam CSY, Tang WC, Tse DY, et al. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: a 2-year randomized clinical trial. Br J Ophthalmol. May 29, 2019. [Epub ahead of print].|