A fundamental goal for clinicians is to facilitate better vision-specific quality of life for patients with age-related macular degeneration (AMD). To that end, the market is replete with low vision aids. But a new study shows that one such device, a spectacle lens for AMD patients, only slightly increases visual acuity (VA), and does not significantly improve quality of life.
The lenses, which have been available for approximately a decade, combine low-power prism, 6% magnification, yellow-tinting, and anti-reflective coating. Prior studies have focused on these elements individually. Researchers measured quality-of-life outcomes for 190 subjects in everyday functioning, and analyzed visual acuity and contrast sensitivity after using the lenses.
Patients at low-vision clinics who were diagnosed with macular degeneration, were older than 18 years, and indicated a benefit from the device at their initial visit were selected during the study period (September 2014 to July 2016). Researchers also looked at 86 control patients. Both those in the study and control groups completed a vision-specific, 25-item quality-of-life questionnaire. In addition, VA and contrast sensitivity were measured after 6 weeks with the patients’ current optimal refraction alone, and together with the lenses.
No statistically significant differences were observed between the device and control groups on the 25-item National Eye Institute Visual Function Questionnaire Rasch score (d=-0.07, P =.53) and the composite score (d=0.14, P =.22), according to the researchers.
Contrast sensitivity and VA improved slightly with device, and “this change in VA was statistically significant with averages of 0.05 logMAR for the better-seeing eye (2.5 letters, P <.001), 0.01 logMAR for the worse-seeing eye (1 letter, P <.001), and 0.05 logMAR for both eyes (2.5 letters, P <.001),” the study authors said. However, because a 0.05 logMAR difference was less than the 0.20 logMAR test-retest mark, they added that this improvement was not clinically meaningful.
Investigators speculate that better quality-of-life scores might be realized with a longer follow-up period. In addition, they suggest spectacle lenses for macular degeneration may be of greater benefit to those with a particular level of visual function, perhaps to gain “more in the middle range of visual acuity.”
Study subjects scored significantly lower than an age-matched general population sample on the 25-item National Eye Institute Visual Function Questionnaire — with scores of 51.8 vs. 86.0, respectively, out of 100. Another survey for general quality of life, the EuroQol 5-Dimension 5-Level, also demonstrated lower scores. Researchers suggest that patients’ social and role functioning may be affected by low vision that accompanies AMD. They caution, though, that the analysis did not correct for factors such as comorbidity and socioeconomic status.
Due to the high burden of AMD, there is a continuing need for the development of effective low-vision aids, and new electronic eyeglass technology is promising, researchers added.
Disclosure: Study authors declared affiliations with relevant device manufacturers. Please see the original reference for a full list of authors’ disclosures.
Visser M, Timman R, Kampen-Smalbrugge J, Buis K, Polling J, Busschbach J. Randomized controlled trial of a spectacle lens for macular degeneration, OptomVis Sci. 2020;97:889–897. doi:10.1097/OPX.0000000000001588.