Assessment and management of children with visual impairment

Abstract

Purpose:The aim of this work was to evaluate the role of low vision aids in improving visual performance and response in children with low vision.Study Design:Prospective clinical case series.Materials and Methods:This study was conducted on 50 patients that met the international criteria for a diagnosis of low vision. Their ages ranged from 5 to 15 years. Assessment of low vision included distance and near visual acuity assessment, color vision and contrast sensitivity function. Low vision aids were prescribed based on initial evaluation and the patient's visual needs. Patients were followed up for 1 year using the tests done at the initial examination and a visual function assessment questionnaire.Results:The duration of visual impairment ranged from 1 to 10 years, with mean duration ± SD being 4.6± 2.3299. The near visual acuities ranged from A10 to A20, with mean near acuity ± SD being A13.632 ± 3.17171. Far visual acuities ranged from 6/60 (0.06) to 6/24 (0.25), with mean far visual acuity ± SD being 0.122 ± 0.1191. All patients had impaired contrast sensitivity function as tested using the vision contrast testing system (VCTS) chart for all spatial frequencies. Distance and near vision aids were prescribed according to the visual acuity and the visual needs of every patient. All patients in the age group 5-7 years could be integrated in mainstream schools. The remaining patients that were already integrated in schools demonstrated greater independency regarding reading books and copying from blackboards.Conclusion:Our study confirmed that low vision aids could play an effective role in minimizing the impact of low vision and improving the visual performance of children with low vision, leading to maximizing their social and educational integration.

Assessment of near visual acuity in 0–13 year olds with normal and low vision: a systematic review

“…In the 12 children with N8 or worse low vision aids were considered.Hohmann 1982 [31]Cross sectional n  = 62Group = NVAge = 6–12 yearsTest: Binocular Landolt C-testRange: 0.1–1.4 (decimal acuity)Spacing: 2.6′ and 17.2′Distance: 40 cm (and 6 m)Threshold: 88–94%Response: Verbal or matchingThe majority of subjects had vision of 1.4 (decimal).Maximum acuity uncrowded optotypes at 7 years and crowded optotypes at around 10 years.Dowdeswell 1995 [23]Cross sectional n  = 68Group = NVAge = 5;2–7;6 yearsTest: Monocular Bailey-Lovie chart at 0.3 and 6 mRange: 0.1–2.0Spacing: 1× optotype sizeDistance: 30 cm and 6 metresResponse: Not specifiedSee Fig. 3.Lovie-Kitchin 2001 [30]Cross sectional n  = 71Group = low visionAge = 7–18 yearsTest: Binocular near text visual acuity (reading test based on the Minnesota Low Vision Reading Test) and distance visual acuity (Bailey-Lovie chart)Spacing: not specifiedDistance: 10 cm and 3 metresThreshold: DVA scored per letterResponse: readingDistance vision ranged from 0.10–1.28 logMAR and near text visual acuity from 0.12–1.47 logMAR (N 1.5-N24 at 10 cm).Critical print size: 0.74–1.87 logMAR (N5-N64 at 10 cm).Labib 2009 [29]Cross sectional n  = 50Group = low visionAge = 5–15 years (mean age 11 ± 2.6 y)Test: Monocular near (Keeler’s reading chart) and distance (Landolt C)Distance: 25 cmSpacing: Not specifiedResponse: VerbalThe near visual acuities ranged from A10 to A20, with the mean near acuity ± SD being A13.632 ± 3.17171.DVA ranged from 4/60 (0.06) to 6/24 (0.25), with mean distance visual acuity ± SD being 0.12 ± 0.12.Boonstra 2012 [21]Non-randomized controlled trial n  = 21Group = low visionAge = 3 ½–6 yearsTest: Binocular LEA near chartDistance: self-chosen distance, at 40 cm and at 3 metresSpacing: 0.5 and 1.0× letter sizeResponse: VerbalSee Fig. 4.Dekker 2012 [22]Cross sectional n  = 62Group = NVAge = 4–12 yearsTest: Binocular LEA line and single at near and distanceDistance: 0.3 and 3 metresSpacing: 0.5 and 1.0× letter sizeResponse: VerbalDistance vision crowding ratio (95% CI):4–6y: 1.40 (0.88–2.22)6–12: 1.31 (0.87–1.97)Near vision crowding ratio:4–6y: 1.01 (0.55–1.86)6–12y: 1.01 (0.72–1.42)Huurneman 2012 [27]Cross sectional n  = 58/ n  = 75Group = low vision/NVAge = 4–8 yearsTest: Binocular C-test and LEA line at near/C-test at distanceDistance: 40 cm and 5 metres (if children had acuity < 20/125 distance was reduced to 2.5 metres at distance).Spacing: C-test: 2.6 and > =30; LEA line test 0.25, 0.5 and 1.0 × letter sizeThreshold: 60% (3/5)Response: VerbalSee Fig.…”

Impact of low vision rehabilitation on functional vision performance of children with visual impairment

“…An appropriate timing is important to allow a time lapse for the patient to have a full benefit with the LVD as well as not to make it too long after rehabilitation that results in fall of the of baseline levels owing to progressive nature of certain low vision eye conditions. [ 13 ]…”

Quality of life in children with low vision following use of low vision aids

“…Various studies have reported favorable outcome in the improvement of QOL in visually impaired children following use of LV aids (LVAs). [ 5 7 14 15 16 17 18 ] Children with useful residual vision can benefit from spectacles and LVAs, thus emphasizing the need for visual rehabilitation in these “incurably blind children. [ 7 8 ]…”