Abstract
Purpose :
To assess the long-term stability of clinical measures of convergence (near point of convergence [NPC] and positive fusional vergence [PFV]) in 9- to 14-year-old children enrolled in the Convergence Insufficiency Treatment Trial-Attention & Reading Trial (CITT-ART).
Methods :
310 children ages 9 to 14 years with symptomatic CI were randomized in a 2:1 ratio to 16 weeks of office-based vergence/accommodative therapy or placebo therapy, respectively. At the 16-week primary outcome, children who were asymptomatic were assigned maintenance therapy and those who were symptomatic were offered treatment. NPC and PFV were measured 1 year after completion of the 16-week visit. We compared findings and the percentages of children with normal (<6cm) and/or improved NPC (≥4cm) and normal (passing Sheard’s criterion and base-out break >15pd) and/or improved PFV (≥10pd) at 16 weeks and 1 year.
Results :
Of participants who completed the 16-week outcome, 88.8% returned at 1 year (90% assigned to vergence/accommodative therapy; 86% assigned to placebo therapy). For participants in the vergence/accommodative therapy group who did not report any additional therapy after 16 weeks, mean adjusted NPC did not significantly change (-0.37cm; 95% CI: -0.97 to 0.23cm) and mean adjusted PFV decreased slightly between 16 weeks to 1 year, but this change was not clinically relevant (-4.80pd; 95% CI: -6.50 to -3.10pd). Thus, NPC and PFV remained clinically normal at 1 year (4.37cm ± 3.2cm and 29.38pd ± 10.4pd, respectively) for vergence/accommodative therapy group participants and there was no significant change in the percentages classified as either “normal and improved” or “normal and/or improved” based on NPC and PFV (P>.086) at year 1 compared to the 16-week outcome. There were no significant changes in the clinical measures of placebo group participants who did not report any additional therapy between the 16-week outcome and 1 year (NPC: 1.03cm, 95% CI: -0.31 to 2.37cm; PFV: 0.54pd, 95% CI:-1.98pd to 3.06pd)(P-values > 0.10).
Conclusions :
Children ages 9 to 14 years old maintained their improvements in clinical measures of convergence after 16 weeks of office-based vergence/accommodative therapy for symptomatic convergence insufficiency. Mean NPC and PFV values at 1 year remained clinically normal.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.