Abstract
Purpose :
To evaluate the shape discrimination threshold in dark, with glare and without glare, before and after LASIK. And to determine the variation of the loss of shape discrimination caused by transient glare.
Methods :
46 myopia patients and 10 normal people were recruited in this study, only the right eyes needed to be measured. Follow-up time included preoperation,1 week，1 month postoperatively. The subject should finish the measurement 3 times both with glare and without glare. The shape discrimination threshold with/without glare was defined as R(on)/ R(off). The difference between R(on) and R(off) was equal to R(glare), which represented the loss of shape discrimination caused by transient glare.
Results :
R(on) was significantly larger than R(off) all the time in both control and experimental group. Comparison of R(off),R(on),R(glare) showed: 1. Preoperative and postoperative R(off)showed no difference(F=3.027, P=0.220); 2. Postoperative R(on) decreased significantly over time(F=30.868,P<0.001),furthermore, all of pre-1w(P=0.017),pre-1m(P<0.001),1w-1m(P=0.017) showed significant difference; 3. Postoperative R(glare) decreased significantly over time (F=23.836,P<0.001),furthermore, both pre-1w(P=0.015) and pre-1m(P<0.001) showed significant difference,1w-1m showed no difference(P=0.126). 4. All of R(off), R(on), R(glare) showed no difference among measurements in control group (R(off): F=2.314, P=0.127; R(on): F=2.020, P=0.162; R(glare): F=1.979,P=0.167).
Conclusions :
After LASIK, the shape discrimination threshold without glare kept stable; the shape discrimination threshold with glare decreased which indicated more subtle shape discrimination; the postoperative influence caused by disability glare on shape discrimination seemed slighter, and trended to be steady after 1month.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.