Clinical test responses to different orthoptic exercise regimes in typical young adults

Abstract

PurposeThe relative efficiency of different eye exercise regimes is unclear, and in particular the influences of practice, placebo and the amount of effort required are rarely considered. This study measured conventional clinical measures following different regimes in typical young adults.MethodsA total of 156 asymptomatic young adults were directed to carry out eye exercises three times daily for 2 weeks. Exercises were directed at improving blur responses (accommodation), disparity responses (convergence), both in a naturalistic relationship, convergence in excess of accommodation, accommodation in excess of convergence, and a placebo regime. They were compared to two control groups, neither of which were given exercises, but the second of which were asked to make maximum effort during the second testing.ResultsInstruction set and participant effort were more effective than many exercises. Convergence exercises independent of accommodation were the most effective treatment, followed by accommodation exercises, and both regimes resulted in changes in both vergence and accommodation test responses. Exercises targeting convergence and accommodation working together were less effective than those where they were separated. Accommodation measures were prone to large instruction/effort effects and monocular accommodation facility was subject to large practice effects.ConclusionsSeparating convergence and accommodation exercises seemed more effective than exercising both systems concurrently and suggests that stimulation of accommodation and convergence may act in an additive fashion to aid responses. Instruction/effort effects are large and should be carefully controlled if claims for the efficacy of any exercise regime are to be made.

Should amblyopia be treated?

“…Thus, the RCT results showing significant improvements in the groups designated as ‘untreated’ raise important questions about which factors, such as repeat visual acuity testing, might themselves represent active components of a treatment protocol. Indeed the topic of practice also features prominently in relation to therapy for binocular disorders in the paper by Horwoord and Toor in the current issue.…”

Recommendations for analysis of repeated‐measures designs: testing and correcting for sphericity and use of manova and mixed model analysis

“…[15][16][17] Various examples of the use of this analysis have been published in the ophthalmic literature including as an alternative to RM-ANOVA. [43][44][45][46] Other studies have used MMA in combination with conventional ANOVA. 47,48 MMA has also been used in studies Table 1.…”

Convergence accommodation in orthoptic practice

“…We studied a large group of young adults given a range of different orthoptic exercises. 24,25 Convergence exercises (even to a non-accommodative target) helped convergence and accommodation much more than accommodation exercises.…”

“…In our study of normal young adults, monocular accommodation facility was particularly prone to pure short-term practice effects. 24 Many people have poor monocular accommodation at first, but rapidly get better just by repeated testing. It appears that monocular accommodation can often be not truly weak, just rarely practised.…”