The effect of a Computer Lens Filter on visual performance in subjects with retinitis pigmentosa

Abstract

Background：Retinitis pigmentosa (RP) patients uauslly complained nyctalopia and poor dark adaptation which caused their visual discomfort, in this study we aimed to explore the effects of a Computer Lens Filter (CLF) on contrast sensitivity (CS), reading speed for computer screen text and visual comfort in subjects with retinitis pigmentosa (RP), and to find wheather CLF would be helpful for RP patients . Method: Twenty-two subjects diagnosed with binocular RP participated. Bright CS using the Mars test and reading speed of screen text were measured using the spectacle corrections for best corrected visual acuity (BCVA) both with and without CLF wear. Subjective estimates of computer screen brightness and visual comfort were evaluated by questionnaire. These functions were compared for the two conditions of filter wear/non-wear. Result： Mean subject age was 38.2±7.5 years and mean log MAR VA was .45± .24. Wearing a CLF neither improved bright CS (t = .452, P=.653) nor increased reading speed (t =.414, P = .683). CLF wear was judged to reduce screen brightness (t = 5.412, P<.0001) and improve visual comfort (t = 6.897, P<.0001). Conclusion： CLF wear neither improved RP subjects’ CS nor reading speed for screen text but did reduce the appearance of screen brightness and improve subjects’ reported visual comfort. Improvement in comfort alone may be sufficient justification for filter use as a vision aid for RP patients during vision rehabilitation.