The Effect of Bifocals in Children With Down Syndrome

Study Overview
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Brief Summary
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Visual acuity at near improves in children with Down syndrome using bifocals

Detailed Description
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The accommodation is consistently reduced in 50 to 100% of children with Down syndrome and does not improve with age.

Official Title
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The Effect of Bifocals in Children With Down Syndrome

Conditions
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Visual Acuity at Near, Accuracy of Accommodation, Prevention of Strabismus, Task Readiness

Intervention / Treatment
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* Device: bifocals
* Device: single vision glasses


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosed with Down syndrome (DS) Accommodation lag >0.5 Dioptres for children with DS <12 years and >0.75 Dioptres for children older than age 12 or Visual acuity at near is worse than at distance and >0.1 Age range 2-14 years Speaks Dutch as the first language Must be verbal or able to understand instructions Must be able to perform a task sitting on a chair and working at a table Exclusion Criteria: Visual acuity at near < 0.1 Not able to do vision tests at age over 5 Has worn bifocals already Other significant eye diseases, such as keratoconus, cataract or high myopia (>S-6.00). Diagnoses of any neurological, sensory or behavioural disorders such as autism, microcephaly or significant hearing loss. Prematurity, born premature after a pregnancy term less than 36 weeks Born after severe perinatal problems

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 14 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: single vision glasses<br>single vision glasses | Device: single vision glasses<br>* single vision glasses<br>|
| Experimental: bifocals<br>bifocal glasses | Device: bifocals<br>* bifocal glasses with an addition of 2.5 Dioptres<br>* Other names: reading glasses;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| • Change from baseline in visual acuity at near measured in decimals and in Logarithm of the Minimum Angle of Resolution (LogMAR) at 16 months. | visual acuity is measured in decimals and in Logarithm of the Minimum Angle of Resolution (LogMAR) at baseline and at the end of the study 16 months later. We will calculate the difference. | baseline to 12 months later | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| • Visual acuity at near measured in decimals and in Logarithm of the Minimum Angle of Resolution (LogMAR) at 16 months. | visual acuity at near measured in decimals and in Logarithm of the Minimum Angle of Resolution (LogMAR) at 16 months. | after 12 months | 
| • Change from baseline in visual acuity at distance measured in decimals and in Logarithm of the Minimum Angle of Resolution (LogMAR) at 16 months. | Visual acuity at distance is measured in decimals and in Logarithm of the Minimum Angle of Resolution (LogMAR) at baseline and at the end of the study 16 months later. We will calculate the difference. | baseline to 12 months later | 
| • Change from baseline in accuracy of accommodation response measured in Dioptres. | We will measure the accuracy of accommodation in Dioptres at baseline and after 16 months. We will calculate the difference. | baseline to 12 months later | 
| • Change in percentage of participants with strabismus | We will calculate the percentage of participants with strabismus at baseline and at the end of the study, 16 months later. Then we can calculate the difference in percentage of participants with strabismus. | baseline to 12 months later | 
| • Change in score of task readiness of the children | We will measure task readiness in scores of attention, reaction time, inhibition and working memory at baseline and at the end of the study 16 months later. Then we calculate the difference in this score. | baseline to 12 months later | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Down syndrome, visual functions, bifocals, children, visual acuity at near