Aim: To evaluate the positive effects of blue-violet light filtering lenses in delaying myopia and relieving asthenopia in juveniles.
Methods: Sixty ametropia juveniles (aged range, 11-15y) were randomized into two groups: the test group (30 children, 60 eyes), wearing blue-violet light filtering lenses; and the control group (30 children, 60 eyes), wearing ordinary aspherical lenses. Baseline refractive power of the affected eyes and axial length of the two groups was recorded. After 1-year, the patients underwent contrast sensitivity (glare and non-glare under bright and dark conditions), accommodation-related testing, asthenopia questionnaire assessment, and adverse reaction questionnaire assessment.
Results: After 1y of wearing the filtering lenses, changes in refractive power and axial length were not significantly different between the two groups (P>0.05). Under bright conditions, the contrast sensitivities at low and medium-frequency grating (vision angles of 6.3°, 4.0°, and 2.5°) with glare in the test group were significantly higher than in the control group (P<0.05), while the contrast sensitivity at low-frequency grating (vision angles of 6.3° and 4.0°) in the absence of glare in the test group was higher than in the control group (P<0.05). Under glare and non-glare dark conditions, the contrast sensitivities of various frequencies in the test group did not show significant differences compared with those in the control group (P>0.05). In the test group, the amplitude of accommodation, accommodative lag, and accommodative sensitivity of patients wearing glasses for 6 and 12mo were significantly elevated (P<0.05), while the asthenopia gratings were significantly decreased (P<0.05). Nevertheless, in the control group, the amplitude of accommodation, accommodative lag, and accommodative sensitivity after 12mo were not significantly altered compared with baseline (P>0.05), and the asthenopia grating was not significantly decreased (P>0.05). In addition, after wearing glasses for 6 to 12mo, the asthenopia grating of patients in the test group decreased significantly compared with the control group (P<0.05). At 12mo, the constituent ratio of adverse reactions did not show significant difference between the two groups (P>0.05).
Conclusion: A 1-year follow-up reveal that compare with ordinary glasses, short-wavelength filtering lenses (blue/violet-light filters) increase the low- and medium-frequency contrast sensitivity under bright conditions and improved accommodation. They effectively relieved asthenopia without severe adverse reactions, suggesting potential for clinical application. However, no significant advantages in terms of refractive power or axial length progression were found compared with ordinary aspheric lenses.
Keywords: asthenopia; juvenile myopia; short-wavelength filtering lenses.