Optical Fogging is an Effective Method of Reducing Overestimation of Myopia

Background To evaluate the effectiveness of optical fogging in reducing overestimation of myopia using an open-field auto-refractor and partial coherence interferometry. METHODS The study recruited 144 young adults with an age range of 17-23 years. Binocular refractive error and biometry parameters were measured using an open automatic refractor and partial coherence interferometry at baseline, under optical fogging, and cycloplegia conditions. The effectiveness of optical fogging in reducing overestimation of myopia was evaluated by comparing the results with cycloplegic refraction. RESULTS A total of 284 eyes were included in the analysis with a mean spherical equivalent (SE) of -3.85 ± 2.56D at baseline. When analyzed the results separately for the overestimation of myopia group and the control group, 28.9% of eyes were classified into the myopia overestimation group. In eyes with overestimation of myopia and overall, optical fogging induced a relaxation in accommodation of 0.28 ± 0.37D and 0.07 ± 0.34D, respectively, compared to the baseline (p for all<0.001); For lens thickness, compared to baseline, changed by 0.02 ± 0.24mm in overestimation of myopia eyes and 0.004 ± 0.20mm in the whole eyes (p for all >0.05). In comparison with the cycloplegic condition, the efficacy of optical fogging in reducing overestimation of myopia is 36.84% and 21.88%, respectively. CONCLUSIONS Optical fogging is an effective method to reduce the overestimation of myopia in young adults. It is recommended to follow the standards for optical fogging during subjective refraction in adults to minimize the impact of myopia overestimation on prescriptions.