Near vision status in a group of Norwegian school children aged 9-16

Title Near vision status in a group of Norwegian school children aged 9-16
Author, Co-Author Ellen Svarverud, Gro Vikesdal, Cecilie Bjorset, Jon Gjelle, Hilde Pedersen, Lene Hagen, Randi Mork, Stuart Gilson, Rigmor Baraas, Trine Langaas
Topic Binocular Vision/Pediatrics
Year
2016
Day
Thursday
Program Number
165001
Room
Ballroom A-B
Affiliation
University of Southeast Norway, Dept. of Optom and Vis Sci
Abstract

Purpose: Vision screening serves an important purpose of identifying children with vision problems, but criteria for what should be considered normal are largely based on text-book values. Here, criteria for near vision measures were assessed in a group of Norwegian children.

Methods: Children in 5th (n=43, 9–10 yo) and 10th (n=53, 15–16 yo) grade participated in the study. The screening program consisted of a symptoms questionnaire, monocular habitual visual acuity at distance (VAd) and binocularly at near (VAn), cover test (CT) distance and near, near point of convergence (NPC), accommodation amplitude (AA) and stereo vision. Non-cycloplegic retinoscopy was performed by an experienced optometrist. Children failing set criteria were referred for a comprehensive eye examination.

Results: There were no differences in mean (SD) values between 5th and 10th graders in visual function, except for spherical equivalent refraction, SER [+0.55 (0.97) DS and +0.09 (0.93) DS, p = 0.02]. LogMAR VAd was 0.01 (0.11) and 0.05 (0.16), VAn -0.01 (0.16) and -0.04 (0.10) for 5th and 10th graders. CT was -0.5 (2.0) ΔD and -1.5 (3.0) ΔD at distance and near (n = 96). NPC was 6.5 (4.0) cm (n = 96) and AA values 12.2 (3.4) D (5th), and 11.0 (2.7) D (10th). A subgroup of non-referred emmetropes (-0.5 D < SER < 1.0 D) were defined as “normals” (n=45). Expected values for NPC and AA were calculated from their mean. Values just outside 95% CI were NPC 6.5 cm, AA 11.7 D (5th) and 10.3 D (10th). Using these values, 26.7% and 29% of our non-referred children may be regarded as having subnormal NPC and AA, while using text-book criteria for NPC (≥7.5 cm) and AA (Hofstetter’s formula) these numbers would be 6.7% and 43%.

Conclusion: Children’s near vision is more important than ever with increased use of near electronic devices. Estimated normal values of NPC and AA differed from text-book values, and further research is needed in revisiting these values.

Affiliation of Co-Authors Optometry and Vis Sci, Univ College of Southeast Norway, Optometry and Vis Sci, Univ College of Southeast Norway, Optometry and Vis Sci, Univ College of Southeast Norway, Optometry and Vis Sci, Univ College of Southeast Norway, Optometry and Vis Sci, Univ College of Southeast Norway, Optometry and Vis Sci, Univ College of Southeast Norway, Optometry and Vis Sci, Univ College of Southeast Norway, Optometry and Vis Sci, Univ College of Southeast Norway, Optometry and Vis Sci, Univ College of Southeast Norway
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