Digital eye strain is becoming more common in children and teenagers. The symptoms of asthenopia can be due to dry eye, binocular vision dysfunction and glare sensitivity – learn more about each of these, as well as guidelines to manage the risks.
While 80% of pre-presbyopic adults with Digital Eye Strain symptoms preferred reading with low-addition lenses, the improvement in reading speed was generally small and did not appear to correlate with specific accommodation or binocular vision dysfunctions. In the 8% who showed a significant improvement in reading rate of at least 15%, a majority showed reduced accommodation amplitude.
After 1 month of wearing orthokeratology lenses, children were shown to have reduced accommodative lag and increased blur sensitivity, leading to the suggestion that blur adaptation is conducive in achieving good visual acuities and visual function in ortho-k wear.
This study examines the effect that dual focus contact lenses have on accommodation and defocus during near viewing, and the results provide clues towards understanding the myopia control mechanism of these contact lenses.
Low-dose atropine (0.05% or less) has a maximum effect on pupil size for both bright and dim light conditions within an hour of instillation, but has little to no effect on binocular vision in myopic children when used for myopia management.
Different designs of soft myopia control contact lenses have different impacts on the accommodation response, sitting alongside previous research which relates this to efficacy. The measurement technique used for accommodation also influences the outcomes.
This paper has found there are numerous correlations but only weak evidence to demonstrate a causal link between accommodation and myopia development. Assessment of the young myope’s accommodation and binocular vision function is still important. More understanding of the underlying mechanisms for myopia is needed in order to develop evidence-based interventions.
This study showed that aspheric multifocal soft contact lenses (Biofinity +2.50D and NaturalVue) reduce accommodative response and increase exophoria, while MiSight concentric dual-focus minimally impacts binocular vision function compared to single vision contact lenses. All myopia control contact lenses increased divergence range slightly but did not impact convergence.
Do you check your patient’s binocular vision function after cycloplegic refraction? Is this useful? An unexpected finding in this case leads to discussion of binocular vision changes in cycloplegic conditions, ideal management for exophores, and even the impact of low-dose atropine.
Binocular vision is a much neglected (and even maligned?) domain of eye care where I’ve had numerous colleagues say their professional excitement and learning opportunities have been reinvigorated through seeing the clinical imperative and application in practice. Not only does binocular vision assessment add so much more to your clinical picture, and make optometric life more interesting, it could be the secret sauce that helps us bridge the gap towards 100% efficacy.
