Abstract
Purpose :
To evaluate the effects of YAG laser vitreolysis of floaters on visual function and vitreous structure.
Methods :
Patient satisfaction was evaluated with the NEI Visual Function Questionnaire (VFQ). Visual function was assessed by measuring visual acuity (VA; Snellen decimal) and contrast sensitivity (CS; Freiburg Acuity Contrast Testing; %W) in 28 eyes of 28 patients with clinically significant floaters; 14 had prior YAG laser vitreolysis. As previously described (IOVS 56:1611–17, 2015) vitreous structure was evaluated with quantitative ultrasound (QUS; AVISO, Quantel, France) to measure 3 parameters: Energy, the sum of the square of the acoustic values within the central/posterior vitreous divided by the area of measurement; P50, the percentage of the central/posterior vitreous filled by echogenic clusters greater than 50 pixels (0.069 mm); and Mean, the mean of the acoustic values divided by the area of the central/posterior measurement area. Two scan orientations were employed: Long (longitudinal to the limbus through the plane of the macula) and LMAC (horizontal longitudinal through the plane of the macula).
Results :
There was no difference in VFQ between YAG-treated (76 ± 6) and untreated eyes (74 ± 6; P=0.3859). There were also no differences in VA (YAG: 0.64 ± 0.2 vs. non-YAG: 0.66 ± 0.15; P<0.82), or CS (YAG: 4.80 ± 1.97 %W vs. non-YAG: 4.07 ± 1.07 %W; P<0.22). In YAG-treated eyes, QUS detected less backscatter (Energy; LMAC = 614 ± 233 in YAG-treated vs. 820 ± 279 in untreated; P<0.037; longitudinal = 513 ± 135 in YAG-treated vs. 670 ± 194 in untreated; P<0.017) and a lower mean acoustic value (Mean; LMAC = 22 ± 4 in YAG-treated vs. 25 ± 4 in untreated; P<0.045; longitudinal = 20 ± 2 in YAG-treated vs. 23 ± 3 in untreated; P<0.02). Total vitreous echodensity (P50) trended lower in YAG-treated vs. untreated eyes (LMAC = 2.48 ± 3.36 vs. 5.25 ± 4.50; P=0.067; longitudinal = 1.64 ± 1.85 vs. 3.45 ± 3.15; P=0.068).
Conclusions :
Vitreous particle sizes and total vitreous echodensity were reduced in YAG-treated eyes compared to untreated eyes, but VA and CS were the same as untreated eyes, suggesting no improvement in patient satisfaction nor vision improvement by YAG vitreolysis. Thus, in spite of apparent structural effects, YAG laser vitreolysis does not appear to improve patient satisfaction and visual function as has been experienced with vitrectomy (Retina 34:1062-8, 2014; Surv Ophthalmol 61:211-27, 2016).
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.