Kids and dry eye
Only a minimal percentage of children are likely to suffer dry eye symptoms (4%) compared to 56% in adult contact lens wearers.(1) Teens may be more likely to report contact lens related dry eye than younger children,(2) and consideration should be given to any systemic medications which could exacerbate dry eye symptoms, such as acne medications and those taken for anxiety and depression.(3) We are yet to learn whether the digital lifestyle of children and teens today may lead to an increase in dry eye complaints, as may be the case for adults(4) – consideration should be given to selection of contact lens material to optimise comfort and encourage ongoing successful wear through the years.
The most common comfort consideration is likely to be allergy, either in reaction to contact lens wear or secondary to the growing incidence of childhood allergy. Around 10% of children suffer allergic rhinitis (hayfever) which has a 90% association with ocular allergy.(5) A history of allergic rhinitis (hayfever), though, isn’t necessarily a contraindication to contact lens wear. Daily disposable lenses have in fact been shown to act as a barrier to environmental allergen exposure – a small study of 10 young adults with confirmed allergic sensitivity to grass pollen, where they thrust their faces into a high pollen count chamber and pelted them with allergens (must have been university student volunteers who were promised extra credit!), showed reduced symptoms of burning and stinging, reduced duration of symptoms and reduced bulbar hyperaemia, corneal and conjunctival staining when daily disposable lenses were worn.(6)
Binocular vision and dry eye
It is understood that binocular vision (BV) disorders can cause asthenopia,(7) and interestingly they have also been linked to dry eye. A study investigating the relationship between contact lens induced dry eye symptoms and BV disorders found a significant correlation between severity of symptoms on the Ocular Surface Disease Index (OSDI) survey and those found with the Convergence Insufficiency Symptom Survey (CISS). This correlation was found to be greater than any correlations found between OSDI and signs of dry eye – this means that the dry eye symptoms were more closely linked to BV symptoms than the dry eye symptoms were linked to dry eye clinical signs. The authors stated that the similar set of symptoms could lead a clinician to confuse a BV disorder for a dry eye diagnosis.
A second investigation by the same authors evaluated the incidence of BV disorders in non-presbyopic (young) adult myopic contact lens wearers with self-reported dry eye symptoms. They were found to have a 48% prevalence of a BV disorder, with the most common (48%) being an accommodative lag of 1D or more, and the second most common (31%) being pseudo-convergence insufficiency – increased near exophoria and/or reduced base-out fusional reserves at near in presence of accommodative lag of +0.75D or more. While contact lens discomfort can be influenced by a variety of factors, the authors recommended that clinicians consistently assess symptomatic contact lens wearing dry eye patients for BV disorders, to direct best treatment.(8)
Putting BV into practice
The association between myopia and BV disorders means that detecting and managing these conditions can provide benefit to identifying the at-risk potential myope; for paediatric myopia control in spectacles or contact lenses; for consideration of fitting contact lenses; and even for managing contact lens discomfort and dry eye. For practitioners interested to reinvigorate their BV practice and hence providing the best possible vision care to patients of all ages, it may be time to dust off your retinoscope, find some flippers and take advantage of resources available to help you in this important realm of primary eye care.
Check out the Expand my Clinical Skills portal of this site for loads more resources and cases on binocular vision.
Read about how I include BV in my myopia management strategies in the blog Selecting an option – Decision Trees, and put it into action yourself with our new Clinical Management Infographic Which option to slow myopia?
In the series of four blogs for ‘BV February’, as I have unilaterally decreed it to be, 😉 you can also read about:
Specs to contacts – what happens to BV?
The esophoric myope and contact lenses
What about the exophores?
Go forth and BV!
ANNOUNCEMENT: I'm excited to reveal that we're currently working hard on an online educational course called 'Binocular Vision Fundamentals' - all about practical diagnosis and management, with a particular focus on myopia control. I will show you how to assess binocular vision, sytematically manage disorders and improve your clinical skills - this course is relevant to all paediatric practice, not just myopia. I expect it will be ready for release in April 2019. Sign up to our email list at the bottom (mobile) / bottom right (desktop) of this page for advance notice of release, and keep an eye out for updates in the Myopia Profile Facebook group!