Abstract
Purpose :
With evolving technology and accessibility being applied to the field of low vision, patients are finding it easier to maintain independence and accomplish functional goals through the use of electronic magnification. Head borne video displays are a new category of wearable electronic magnifiers (WEMs) marketed for low vision. Compared to their portable and stationary counterparts, there are few studies to date evaluating WEMs. The purpose of this study is to provide comparative data on subject’s objective and subjective responses with the latest models of WEMs: E-Sight Eyewear (E), IrisVision (I), and Jordy (J).
Methods :
A within subject, randomized design, was used to evaluate 25 subjects with stable visual impairments. Effort was made to eliminate gender, pathology, and pattern of vision loss bias with equal subject recruitment. With each WEM, objective measures of distance (D) and near VA and contrast sensitivity were obtained. Subjective measures included reading a newspaper article and completing a 1-5 Likert based survey on factors including: comfort, image quality, cosmetic appearance, field of view, readability, focusing speed, and interest in purchacing the WEM. Subjects also ranked the three WEMs in order of overall preference/performance and perceived cost of each WEM.
Results :
Average number of lines gained in DVA with WEM: J:4.76, E:3.92, I:4.48. Based on a paired t-test, the J and I provided a larger improvement in lines of DVA gained when compared to the E (J vs. E P=0.006; I vs. E P=0.006). Percent of subjects achieving a DVA of 20/40 or better: J:84%, E:68%, I:96%. Percent of subjects giving highest rank based on perceived cost of WEM (actual cost): J:24% ($3,620), E:20%($9,995), I:56% ($2,500). Percent of subjects giving highest rank based on overall preference/performance: J:8% E:20% I:72%
Conclusions :
WEMs allow individuals with low vision an enhanced ability to carry out activities of daily living. All WEMs studied provided significant improvement in distance visual acuity; with the IrisVision receiving the highest rank based on both overall preference/performance and perceived cost, although it is the least expensive WEM of the three compared. This pilot study provides practitioners data to compare initial device outcome and experiences in various patient subgroups in order to assist in recommending whether such devices are suitable for their patient's visual goals and demands.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.