Purpose:
To evaluate the impact of an optoelectronic visual aid prototype (Spanish acronym SERBA) on the visual capabilities of low vision patients. This versatile aid achieves real-time video processing with low cost portable systems. It is based on reconfigurable hardware which makes it easily adaptable to different pathologies (that require diverse processing tasks) and also to the pathology evolution.Inspired in the Visual Multiplexing context [Peli 2001, Optom Vision Sci,78:304], it should not compromise the residual vision, and at the same time restore the loss in visual field (VF) or acuity (VA).
Methods:
We have measured VA (EDTRS), VF (Kinetic perimetry), and contrast sensitivity (CSV-1000E) while using the SERBA, in simulated and real patients suffering from either tunnel vision or VA loss.In the case of tunnel vision, subjects also walked through an obstacle route with and without aid to evaluate their obstacle avoidance capabilites, and they stated their opinion about the aid by questionnaire filling.
Results:
The residual VA and VF was not affected, while contrast sensitivity was only slightly reduced in real patients. The enhanced VA and VF were increased up to the device limits (typically AV=1, and 3-4 times VF expansion)Even though objective differences in mobility and obstacle avoidance were not significant, questionnaire results showed preference for the aids and a positive evaluation of its usefulness.
Conclusions:
The proposed aid does not compromise the residual field, while enhancement of visual performance is achieved in both VF and VA loss.In the case of mobility, patients showed preference for the aid, even further adaptation is required
Keywords: low vision • visual fields • quality of life