Refraction and visual acuity in a national Danish cohort of 4-year-old children of extremely preterm delivery
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Hans C Fledelius1, Regitze Bangsgaard1, Carina Slidsborg1
1Copenhagen University Eye Departments, Glostrup Hospital & Rigshospitalet, Copenhagen, Region Hovedstaden, Denmark.
Insights
Laser treatment for retinopathy of prematurity (ROP) in extremely preterm infants showed fair ophthalmic outcomes at age 4. Most treated infants achieved good vision, differing from earlier US studies.
Area of Science:
- Ophthalmology
- Neonatal care
- Developmental pediatrics
Background:
- Increased laser treatment for retinopathy of prematurity (ROP) necessitates evaluating long-term ophthalmic outcomes.
- Extremely preterm infants face unique challenges in visual development.
Purpose of the Study:
- To assess the ophthalmic and developmental status of extremely preterm survivors at preschool age.
- Specifically evaluate refraction and visual acuity in relation to ROP treatment.
Main Methods:
- A national cohort of 178 preterm (PT) infants (<28 weeks gestation) and 56 full-term (FT) controls were evaluated at age 4.
- Cycloplegic refraction, keratometry, and visual acuity (HOTV, logMAR) were measured.
Main Results:
- Preterm infants showed a myopic tail (4.5%) and hyperopic tail (11.9% ≥+2.5 D) with more curved corneas.
- Visual acuity was generally good; median logMAR visual acuity was 0.2 in PT vs. 0.1 in FT.
- Lower visual acuity (≤0.5 Snellen) was associated with ROP stage 3 or higher; two children had low vision.
Conclusions:
- Overall fair ophthalmic outcomes for preterm infants align with recent European data.
- Diode laser ablations for ROP were effective, with most treated children achieving good social vision.
- Outcomes differ from earlier US studies, suggesting improved management or treatment protocols.
Purpose:
A recent threefold increase in laser treatment for advanced retinopathy of prematurity (ROP) triggered a nationwide preschool ophthalmic and developmental status among extremely preterm survivors. Here, we discuss refraction and visual acuity.
Methods:
Survivors (n = 178) from a national birth cohort (February 2004 to March 2006) of gestational age <28 weeks (PT) and 56 full-term (FT) controls attended for evaluation at age 4 years. Cycloplegic refraction and keratometry were achieved by Retinomax autokeratorefractor and visual acuities by symbol recognition (HOTV, logMAR).
Results:
The refractive distribution presented a myopic tail (4.5%) and a hyperopic tail (11.9% ≥+2.5 D) as special preterm features, and corneas were more curved. Astigmatism and anisometropia were only marginally increased, and visual acuities were generally good. Best-corrected binocular median logMAR visual acuity was 0.1 in FT and 0.2 in PT, in Snellen equivalents 0.8 and 0.63. Snellen acuity ≤0.5 occurred across the ROP subgroups, but mainly in those with at least ROP stage 3. Two children had low vision.
Conclusions:
The overall fair outcome for refraction and function is in accordance with other recent northern Europe experience. The results differ in particular from the poorer ophthalmic outcomes reported in the pioneer US treatment studies (cryotherapy for ROP and ETROP). The diode laser ablations (n = 32) appeared effective in our series; except one child, all treated subjects had good or fair social vision at the age of 4 years.
