Abstract:  Objective To observe whether there is a synergistic effect between 0.05 D precise full correction technology and defocus incorporated multiple segments technology in delaying myopia progression. Design Pretrospective comparative case series. Participants 241 children who underwent frame glasses fitting at Optometry Center of Beijing Tongren Hospital from 2020 to 2022. Method According to the lens chosen by the parents, 241 children were fitted with 0.05 D spherical interval single vision group (63 cases), 0.25 D spherical interval single vision group (57 cases), 0.25 D spherical interval defocus group (61 cases), and 0.05 D spherical interval defocus group(60 cases). The fitting data including age, gender, refractive error, interval time between the two refractions, lens type of the above children in the electronic medical record system was retrospective analyzed. The refraction methods and environment of the four groups of patients were consistent, and the only difference was whether 0.05 D precise full correction technology was used in the central area of the frame eyeglasses and whether defocus incorporated multiple segments technology was used in the periphery of the lens. The data of the right eye were analyzed statistically. Main Outcome Measures Equivalent spherical change. Results The ages of the 0.25 D spherical interval single vision group, the 0.05 D interval single vision lens group, the 0.25 D spherical interval defocus group, and the 0.05 D interval defocus group were not significantly different (F=0.996, P=0.320). The mean equivalent spherical degrees at the first visit were (-2.10±1.77) D, (-2.00±1.34) D, (-1.97±0.89) D, and (-2.03±0.88) D, respectively (F=0.118, P=0.949). After 6 months of wearing glasses, the equivalent spherical changes in the four groups of patients were (-0.51±0.52) D, (-0.31±0.35) D, (-0.31±0.27) D, and (-0.15±0.26) D, respectively (F=9.503, P<0.001). The equivalent spherical changes in the 0.05 D interval single vision group (P=0.003), the 0.25 D interval defocus group (P=0.004), and the 0.05 D interval defocus group (P<0.001) were significantly smaller than those in the 0.25 D spherical interval single vision group. There was no significant difference in equivalent spherical changes between the 0.05 D interval single vision group and the 0.25 D interval defocus group (P=0.932). The equivalent spherical change in the 0.05 D interval defocus group was significantly smaller than that in the 0.05 D interval single vision group (P=0.018) and the 0.25 D interval defocus group (P=0.015). Conclusion 0.05 D precise full correction technology and defocus incorporated multiple segments technology showed a synergistic effect in delaying myopia progression due to different mechanisms of action. (Ophthalmol CHN, 2023, 32: 282-286)

Key words: myopia, 0.05 D precision full correction technique, defocus incorporated multiple segments technique