Defocus Incorporated Multiple Segments (Dims) Lenses: A Novel Perspective in Myopia Progression Management in a Tertiary Eye Care Center, Assam

Aim: To evaluate the effectiveness of Defocus Incorporated Multiple Segments (DIMS) spectacle lenses compared with conventional single-vision lenses in controlling myopia progression over a 12-month period, using changes in spherical equivalent refraction (SER) and axial length as outcome measures. Methods: This prospective, randomized, hospital-based comparative study included 50 myopic patients who met the inclusion criteria. Participants were randomly allocated into two groups: a control group fitted with single-vision spectacle lenses (n = 25) and an intervention group fitted with DIMS spectacle lenses (n = 25). Baseline evaluations included demographic data, cycloplegic SER, and axial length measurements. There were no statistically significant differences between groups at baseline (p > 0.05). Follow-up assessments of SER and axial length were conducted after 12 months. Intragroup changes were analyzed using paired statistical tests, while intergroup comparisons were performed using independent statistical analyses. Results were expressed as mean changes with 95% confidence intervals (CI), and statistical significance was set at p < 0.05. Results: After 12 months, the single-vision lens group demonstrated significant myopia progression, with mean SER worsening from −4.40 D at baseline to −5.11 D, representing a mean myopic shift of −0.71 D (95% CI: −0.62 to −0.80; p < 0.001). Axial length in this group increased from 24.60 mm to 25.40 mm, with a mean elongation of 0.80 mm (95% CI: 0.72 to 0.88; p < 0.001). In contrast, the DIMS lens group exhibited significantly slower progression. Mean SER changed from −4.32 D to −4.90 D over 12 months, corresponding to a mean shift of −0.58 D (95% CI: −0.50 to −0.66; p < 0.001). Mean axial length increased marginally from 24.95 mm to 25.08 mm, with a mean elongation of 0.13 mm (95% CI: 0.08 to 0.18; p < 0.001). Intergroup comparisons revealed that both the myopic shift in SER and axial elongation were significantly lower in the DIMS group compared with the single-vision group (SER difference: 0.13 D, p = 0.02; axial length difference: 0.67 mm, p < 0.001). Conclusion: DIMS spectacle lenses were significantly more effective than single-vision lenses in slowing both refractive progression and axial elongation over a 12-month period. The statistically and clinically meaningful reduction in axial growth supports the role of DIMS lenses as a safe, non-invasive, and effective optical intervention for myopia management in routine clinical practice.