Interventional procedure overview of YAG laser vitreolysis for symptomatic vitreous floaters

Subjective assessment

In the randomised controlled trial of 52 people (52 eyes), based on a 5-level scale (worse, less than 0%; same, 0%; partial success, 30% to 50%; significant success, 50% to 70%; and complete success, 100%), 53% (19/36) of people in the YAG laser group reported their symptoms as significantly or completely better compared with 0% in the sham group at 6-month follow up (Shah 2017). The difference between the 2 groups was statistically significant at 6 months (difference, 53%; 95% CI 36% to 69%; p<0.001).

In the case series of 34 people, based on a 5-level scale, 50% of people stated that their floaters were significantly or completely better at a mean follow up of 2.3 years compared with 41% at 6 months (p=0.47; Shah 2020).

In a case series of 51 people (51 eyes) with symptomatic floaters, based on a 5-level scale, 71% (36/51) of people reported their symptoms as significant or complete improvement at 6-month follow up. The difference between PVD and non-PVD groups was not statistically significant at 6 months (73% compared with 69%, p=0.344; Lin 2021).

In the randomised controlled trial of 21 people (21 eyes), on a 4-level scale (same or worse, 0%; limited success, 30% to 50%; significant success, 50% to 70%; complete success, 100%), the proportion of people who reported significant or complete improvement was 77% in the YAG laser vitreolysis group and 25% in the control group at 6-month follow up (Ludwig 2021).

In a case series of 50 people (55 eyes) with symptomatic vitreous floaters, the proportion of eyes that had significant or complete success was 56% (31/55) at 6-month follow-up (Sun 2019). When considering the floater severity, the proportion of eyes that had significant or complete success was 71% (12/17) of eyes with preoperative mild floaters, 57% (12/21) of eyes with preoperative moderate floaters, and 41% (7/17) of eyes with preoperative severe floaters at 6-month follow up. The difference between groups was statistically significant (p=0.007; Sun 2019).

Objective evaluation

In the randomised controlled trial of 21 people (21 eyes), a masked evaluator graded the fundus photographs on a 4-level scale and found that improvement was greater in the YAG laser vitreolysis group (significant improvement, 53%; limited and complete improvement, 47%; exact data for each improvement were not reported separately) than the sham group (limited improvement, 63%; no improvement 37%) at 6-month follow up (Ludwig 2021).

In the case series of 50 people (55 eyes), based on a 4-level qualitative scale, the infrared fundus images showed that 64% (35/55) of eyes had significant or complete success at 6 months after YAG laser vitreolysis. When considering the floater severity, the proportion of eyes that had significant or complete success was 82% (14/17) of eyes with preoperative mild floaters, 67% (14/21) of eyes with preoperative moderate floaters, and 41% (7/17) of eyes with preoperative severe floaters at 6-month follow up. The difference between groups was statistically significant (p=0.038; Sun 2019).

In the randomised controlled trial of 52 people (52 eyes), a masked grader rated the fundus photographs on a 5-level scale and reported that 94% (34/36) of people in the YAG group had significantly improved or completely resolved floaters compared with 0% in the sham group at 6-month follow up. The difference between groups was statistically significant (difference, 94%; 95% CI 87% to 102%; p<0.001; Shah 2017).

In the case series of 34 people (34 eyes), a masked reviewer evaluated the fundus photographs on a 5-level scale and found that 94% of people were significantly or completely better at a mean follow up of 2.3 years compared with baseline (Shah 2020).

In the case series of 32 people (32 eyes), a masked grader reviewed the colour fundus photographs and reported that complete vitreous opacity improvement was observed in 56% of people (18/32), partial improvement in 38% (12/32), and no change in 6% (2/32) at 6-month follow up (Souza 2020).

Visual Function Questionnaire (VFQ)

In the randomised controlled trial of 21 people (21 eyes), the NEI VFQ-25 scores for general vision and mental health were statistically significantly higher in the YAG laser vitreolysis group than the sham group at 6-month follow up (general vision, 75.8 compared with 59.2, p=0.037; mental health, 84.3 compared with 70.3, p=0.048; Ludwig 2021).

In the randomised controlled trial of 52 people (52 eyes), the NEI VFQ-25 scores for general vision, peripheral vision, role difficulties and dependency were statistically significantly better in the YAG group than the sham group at 6-month follow up (general vision: 69.4 compared with 53.1; difference 16.3; 95% CI 0.9 to 31.7; p=0.04; peripheral vision: 94.4 compared with 82.8; difference 11.6; 95% CI 0.8 to 22.4; p=0.04; role difficulties: 93.1 compared with 75.8; difference 17.3; 95% CI 8.0 to 26.6; p<0.001; and dependency: 98.8 compared with 93.2; difference 5.6; 95% CI 0.4 to 10.8; p=0.03; Shah 2017).

In the case series of 34 people (34 eyes), when comparing with baseline values, there were statistically significant improvements in near vision activities (baseline, 78.7; final, 85.8; difference, 7.1; 95% CI 1.6 to 12.6; p=0.016), distance vision (baseline, 84.6; final, 89.0; difference, 4.4; 95% CI 0.3 to 8.5; p=0.042), mental health (baseline, 71.7; final, 85.7; difference, 14.0; 95% CI 9.1 to 18.8; p<0.001), and role difficulties (baseline, 81.3; final, 93.4; difference, 12.1; 95% CI 5.6 to 18.7; p<0.001) at a mean follow up of 2.3 years (Shah 2020).

In the case series of 50 people (55 eyes), the mean overall NEI VFQ-25 score statistically significantly increased from 71.44 (SD 12.77) at baseline to 88.54 (SD 12.74) at 6 months after YAG laser vitreolysis (t=11.82, p=0.001; Sun 2019).

In the case series of 34 people (34 eyes), the median VFQ-25 score statistically significantly increased from 73.05 (interquartile range [IQR] 19.25) before YAG laser vitreolysis to 93.76 (IQR 8.73) at 10 days after the second session (p<0.01). The median VFQ-39 score also statistically significantly improved from 74.60 (IQR 19.01) to 95.01 (IQR 6.50; p<0.001). Subgroup analysis showed that there were statistically significant differences in the median changes of NEI VFQ‑25 and NEI VFQ‑39 scores between people with myopia and people without myopia (VFQ-25: 20.06 compared with 15.07, p<0.05; VFQ‑39: 22.27 compared with 16.15, p<0.01; Garcia 2021).

In the case series of 32 people (32 eyes) there were statistically significant improvements in the near visual function (z=−2.97; p=0.003; r=0.633) and visual disturbance rate (z=−3.97; p<0.001; r=0.84) at 6 months compared with baseline after YAG laser vitreolysis (Souza 2020).

State-Trait Anxiety Inventory (STAI)

In the case series of 34 people (34 eyes), the median STAI score statistically significantly improved from 38 (IQR 11; p<0.001) before YAG laser vitreolysis to 18 (IQR 19) at 10 days after the second session (Garcia 2021).

Vitreous floaters symptoms questionnaire (VFSQ)

In the case series of 51 people (51 eyes), the composite score, distance activities, near activities, social functioning, peripheral vision and mental health statistically significantly improved after YAG laser vitreolysis (all p<0.05) but not driving (p=0.162). Comparison of the changes in VFSQ‑13 between the PVD group and the non-PVD group showed no statistically significant difference in all domains (distance activities, 9.38 (SD 14.97) compared with 10.80 (SD 12.53); near activities, 3.33 (SD 10.61) compared with 10.23 (SD 16.65); driving, 1.25 (SD 15.12) compared with 2.27 (SD 7.36); peripheral vision, 5.00 (SD 10.26) compared with 9.09 (SD 19.74); social functioning, 7.50 (SD 14.28) compared with 3.41 (SD 8.78); mental health, 7.08 (SD 13.32) compared with 8.71 (SD 15.53); composite score, 5.59 (SD 9.16) compared with 7.42 (SD 9.65); all p>0.05; Lin 2021).