COMPARISON ON THE EFFECT OF NEAR VISION AIDS FOR LOW VISION BY OPTICAL MAGNIFIERS AND MAGNIFIER VIDEO HANDHELD DEVICE

Nguyễn Thị Thu Hiền

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Abstract

Aims: To compare the effect of near vision aids for low vision by optical magnifiers and magnifier video handheld device.      Methods: The descriptive study was conducted in 80 low vision people from 7 to 71 years old. Results: The average power of optical magnifiers was +24.6 ± 11.4 D. The average power of MVHD was +18.8 ± 8.3 D; Near visual acuity: before aids was 20/500 ± 20/630; with optical magnifiers was 20/250 ± 20/500; with MVHD was 20/125 ± 20/320 (p<0.001). The reading distance: before aids was 4.42 ± 2.81cm; with optical magnifiers was 7.74 ± 4.17cm; with MVHD was 16.38 ± 7.26cm (p<0.001). The reading speed: before aids was 23.46 ± 10.52 words/minute; with optical magnifiers was 43.74 ± 22.57 words/minute; with MVHD was 61.2 ± 24.8 words/minute (p<0.001). Conclusion: The near visual acuity, the reading distance, the reading speed of low vision by using the MVHD were much better than the use of the optical magnifiers.

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