Abstract:

 Objective  To explore the visual fatigue induced by watching three dimensional (3D) video using Accommodation Analyzer-1(AA-1) and accommodative functional examination. Design Experimental study. Participants 48 healthy young subjects with refractive status being emmetropia, mild or moderate myopia (sphere degree>-5.0 D, cylinder degree within +1.0 D)，whose corrected visual acuity were 1.0 or more. Methods Each subject was arranged to watch two kinds of stereo television for 40 minutes in two different morning. Television A is the polarized 4K stereo display, and television B is the shutter-glass 4K stereo display. Before and after watching, accommodative functional examination was undergone by phoropter, accommodative response and microfluctuation high frequency (HFC) values were examined by AA-1. Subjective questionnaire (including eye dry, pain, blur, dizzy and headache. Scores are from 1 to 10, the higher score, the severer fatigue) should be finished after watching. The difference between accommodative measures before and after watching each kind of 3D display, and the difference of accommodative measures after watching between two kinds of 3D displays were analyzed. Main Outcome Measures Amplitude of accommodation, positive relative accommodation (PRA), negative relative accommodation (NRA), ratio of accommodation converge to accommodation (AC/A), HFC values, and subjective questionnaire scores. Results After watching television B, the mean value of amplitude of accommodation (13.92±4.13 D) was larger than that (13.22±3.39 D) before watching in right eye (P=0.035); before watching (13.93±3.99 D) in left eye was larger than that (15.28±6.13 D) after watching (P=0.018). After watching television A, the mean value of amplitude of accommodation only in left eye was larger than before watching (P=0.010). After watching television A, the mean value of HFC in right eyes (60.10±10.96 D) and in left eye (61.22±9.00 D) were larger than before watching (60.26±10.74 D in right eye, 61.84±9.67D in left eye) (P=0.450 for right eye, and P=0.001 for left eye). After watching television B, the mean values of HFC in right and left eye (58.45+10.63 D and 59.59+13.09 D, respectively) were smaller than before watching(58.93+11.20 D and 60.87+11.31 D, respectively)(all P=0.000). The score of subjective questionnaire for television A (3.13+2.35) was better than that for television B (3.70+2.27)(P=0.450). Conclusion Watching 3D video induces visual fatigue. Through examining HFC value and accommodative response using Accommodative Analyzer-1, we may objectively measure the extent of accommodative strain and visual fatigue.

Key words: microfluctuate high frequency, Accommodation Analyzer-1, three dimensional video, stereo vision, visual fatigue