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Recently I had a valuable opportunity to speak about children’s eye diseases at a study meeting held for local pediatricians. Thank you very much for listening so attentively.
The doctors asked many practical questions, which reminded me how strong the interest in, and the questions about, everyday practice are. In the hope that smoother cooperation with ophthalmology will help protect children’s visual function, I explain below, in Q&A format, the topics asked about most often.
Q1. How reliable is the Spot Vision Screener (SVS) at 3-year-old checkups, and what referral criteria should be used?
A1. The Spot Vision Screener (SVS) is an objective and useful device, but its accuracy depends greatly on “which referral criteria are used.”It is important to understand the balance between sensitivity and specificity correctly.
The 3-year-old checkup is an extremely important opportunity for the early detection of amblyopia. However, the accuracy of conventional visual acuity testing depends on how well the child cooperates, so the usefulness of the SVS, which allows objective assessment, is increasing.
The SVS is an effective tool for detecting amblyopia risk factors (ARF).
However, you need to understand that its detection accuracy differs greatly depending on which “referral” threshold is adopted.
In one study from Japan, the criteria built into the SVS (Criteria A) were compared with the criteria recommended by the Japanese Association of Strabismus and Amblyopia and others (Criteria J).
- Criteria A: Sensitivity (the proportion of children with a risk factor who are correctly judged positive) was high at 91%, but specificity (the proportion of children without a risk factor who are correctly judged negative) was low at 33%. As a result, few cases are missed, but more children than necessary are referred for detailed examination, and false positives may increase.
- Criteria J: Sensitivity decreased slightly to 85%, but specificity improved to 44%, and unnecessary eye clinic visits could potentially be reduced.
| Criteria | Sensitivity (positive detection rate for ARF) | Specificity (negative detection rate for ARF) | Clinical characteristics |
| Criteria A | 91% | 33% | Few missed cases, but more false positives |
| Criteria J | 85% | 44% | Slightly lower sensitivity, but fewer unnecessary referrals |
In screening, sensitivity and specificity are always in a trade-off relationship.
Prioritizing sensitivity finds more children at risk,
but it also sends children who actually have no problem to an eye clinic, which can increase parents’ anxiety and burden medical institutions.
When interpreting SVS results, it is essential to know which criteria were used and to understand their characteristics.
Applying the criteria according to the local eye-care system and the purpose of the checkup (comprehensive case-finding or efficient screening) leads to an effective system for detecting amblyopia.
Visual Examination Manual for the 3-Year-Old Checkup(Japan Ophthalmologists Association)
https://www.gankaikai.or.jp/school-health/2021_sansaijimanual.pdf
Q2. What should we look for to find “anisometropic amblyopia” and “microtropia amblyopia,” which are hard to recognize by appearance?
A2. A child’s casual gestures can be important signs.
Anisometropic amblyopia (amblyopia with a large difference in refractive power between the eyes) and microtropic amblyopia are called “silent diseases” because there is no obvious abnormality in appearance. The brain unconsciously suppresses information from the eye that sees poorly, so children rarely complain of any trouble, and parents have difficulty noticing anything wrong.
Even if a parent says, “There seems to be no problem with how they see,” this does not prove normal visual function. Subtle signs to watch for in the exam room include the following.
- Different reactions to covering each eye in turn: If there is a clear difference between the left and right in how much the child objects when one eye is covered by the examiner’s or parent’s hand, it is a strong clue to anisometropic amblyopia. When the better eye is covered, vision suddenly becomes poor, so the child may resist strongly.
- Abnormal head posture (head tilt): The child unconsciously tilts or turns the head slightly, looking for a position where both eyes see comfortably.
- Unstable fixation: Fixation with one eye is unstable, or the gaze is seen to waver slightly.
Considering these observation points together with objective screening results such as the SVS makes more accurate referrals to ophthalmology possible.
Because the condition can progress without any symptoms noticed by the child or the parents, treatment becomes difficult once the sensitive period has passed. It is therefore very important to actively look for latent problems.
Q3. What is the scientific basis for recommending “two hours of outdoor activity a day” to prevent myopia? Is it also effective for children who are already myopic?
A3. Outdoor activity is highly effective for “preventing the onset” of myopia.However, its effect in “slowing” myopia that has already begun to progress is considered limited.
There is sufficient scientific evidence behind the recommendation of “two hours of outdoor activity a day.”
Multiple large meta-analyses have shown that increasing the time spent outdoors strongly prevents the “onset” of myopia.
The mechanism of this effect is thought to involve mainly sunlight, in particular its “light intensity (high illuminance).”
Bright outdoor light stimulates the retina and promotes the release of dopamine, a neurotransmitter.
This dopamine is thought to suppress “axial elongation,” the lengthening of the eyeball from front to back, and thereby prevent myopia.
However, there is a clinical point to note. A detailed analysis of the meta-analysis data shows that
the strong effect of outdoor activity is remarkable for the “prevention of onset” in children who are not yet myopic,
whereas no statistically significant effect has been found for “slowing progression” in children whose myopia is already progressing.
Therefore, we need to convey this fact accurately when explaining to parents.
- For children who have not yet developed myopia (especially those whose parents are myopic), outdoor activity is strongly recommended as a primary prevention strategy.
- For children whose myopia is already progressing, encourage it as a healthy lifestyle habit, but do not expect it to work as a treatment on its own; explain the need for medical intervention such as low-concentration atropine eye drops.
“Playing outside” does not have the same effect on every child,
and we think it is important to explain that the effect varies with the condition of the child’s eyes.
Q4. Why is sunlight better than indoor lighting? What is “violet light”?
A4. Because the “violet light” abundant in sunlight activates a special photoreceptor that suppresses myopia progression.Modern indoor environments can be described as places deficient in this light.
In the course of clarifying how sunlight suppresses myopia, a Japanese research group showed that light of a specific wavelength, violet light (wavelength 360–400 nm), plays an important role.
The mechanism centers on a special photoreceptor in the retina called “OPN5 (neuropsin).”
- OPN5 is a photoreceptor that is not involved in vision itself and specifically senses violet light.
- When OPN5 is activated, it works to maintain the thickness of the choroid, the blood-vessel-rich layer behind the retina.
- Maintaining choroidal thickness is thought to suppress axial elongation.
Modern indoor environments, with UV-blocking window glass and LED lighting, are likely to be “deficient environments” in which violet light is largely blocked.
Blue-light-cut products are also said to be rather harmful for children.
Even when spending time in a “bright room,” children cannot receive enough of the biological signal that is important for suppressing myopia. This provides strong scientific grounds for the question, “Why isn’t it enough just to sit by a window, and why do children actually need to go outdoors?”
Q5. What is “rebound” with low-concentration atropine eye drops (Ryjusea®)?
A5. It generally refers to the phenomenon in which myopia progression accelerates after the drops are stopped, but with the 0.025% formulation (Ryjusea®), the rebound after discontinuation has been confirmed to be small.
Low-concentration atropine eye drops are a drug therapy with established evidence for slowing myopia progression in children. In a clinical trial conducted in Japan (the ORANGE STUDY), the group that used Ryjusea® (0.025%) for two years showed about 39% less progression of refractive error and about 32% less axial elongation than the placebo group.
The “rebound” of concern with atropine treatment refers to a temporary acceleration of myopia progression after the drops are stopped, and it is usually more pronounced with higher concentrations of atropine.
However, in the latest research conducted in Japan (the follow-up of the ORANGE STUDY), a small (concentration-dependent) rebound was observed after stopping treatment even with Ryjusea® (0.025%). Axial elongation in the year after discontinuation was reported to be about 0.32 mm in the 0.025% group and about 0.21 mm in the placebo group. Even so, the rebound after discontinuation tended to be smaller than with high-concentration atropine.
These results support Ryjusea® as a safe and stable means of myopia management.
When explaining this to parents, please convey that “the rebound is smaller than with high-concentration atropine” as a reassuring point, while also stressing the importance of continuing management for an appropriate period, until adolescence or later, when myopia progression settles.
Q6. Is it safe to prescribe orthokeratology to children?
A6. Strict hygiene management at home and attending regular checkups are absolute requirements.If these are met, it can be a safe and effective option.
Orthokeratology (Ortho-K) is a method in which a special lens is worn during sleep to temporarily change the shape of the cornea and improve uncorrected visual acuity during the day. An effect in slowing myopia progression has also been confirmed.
Regarding safety, the Japanese Ophthalmological Society classifies prescription to people under 20 as “prescribe with caution.” This is because the safety of the treatment depends greatly on the ability of the user and the parents to manage it.
Most cases of the most serious complication,corneal infection,result from improper lens care.
The following are absolute requirements when prescribing for children.
- Deep understanding and cooperation of the parents: The parents take the lead and responsibility for cleaning and disinfecting the lenses and managing insertion and removal.
- Adherence to strict hygiene management: The family can reliably perform the lens care recommended in the guidelines every day.
- Strict adherence to regular checkups: The child must attend checkups every three months without fail.
This treatment is not just a “product”; it is closer to a “medical contract” among the ophthalmologist, the parents, and the child. Carefully judging whether the family can truly keep this contract is the first step toward safe treatment.
Q7. What precautions apply when using steroid ointment for atopic dermatitis of the eyelids?
A7. Topical steroids on the eyelids carry a risk of raising intraocular pressure.Switching to tacrolimus ointment or referral to an ophthalmologist should be actively considered.
In children with atopic dermatitis, especially eczema of the eyelids, the use of topical steroids carries a risk of steroid-induced glaucoma.
- Children are at higher risk: Children are more often steroid responders, whose eye pressure responds to steroids more readily than that of adults.
- Eyelid skin is thin: Because eyelid skin is very thin, topically applied steroids are easily absorbed into the eye and can raise intraocular pressure just as eye drops do.
- It progresses without symptoms: Visual field loss from glaucoma causes no symptoms at first. By the time it is noticed, optic nerve damage may already have progressed to a serious level.
In the Japanese guidelines for atopic dermatitis, tacrolimus ointment (Protopic®), which carries no risk of raising intraocular pressure, is recommended as a safe alternative for treatment around the eyes.
For pediatricians, we ask that steroids for the eyelids be limited to as short a period as possible,
and, if treatment is prolonged, we believe it is very important not to hesitate to switch to tacrolimus or refer to an ophthalmologist.
In particular, when continued use for more than two weeks is expected, we strongly recommend requesting an intraocular pressure measurement at an eye clinic.
Thank you for reading to the end in the midst of your busy practice.
We hope this article is of some help in your daily practice.
References
- Hayashi S, Suzuki I, Inamura A, et al. Effectiveness of the Spot Vision Screener in screening 3-year-old children with potential amblyopia in Japan. Jpn J Ophthalmol. 2021;65(4):537-545. doi:10.1007/s10384-021-00823-xpt. 2023;52:93-98.
https://pubmed.ncbi.nlm.nih.gov/33646435/ - Suzuki M, Mori T, Matsuno N, et al. Considerations on criteria for abnormal refractive power determination with the Spot™ Vision Screener in 3-year-olds. Journal of the Japan Orthoptist Association. 2022;52:93-100. doi:10.4263/jorthoptic.52F112 https://doi.org/10.4263/jorthoptic.52F112
- Xiong S, Sankaridurg P, Naduvilath T, et al. Time spent in outdoor activities in relation to myopia prevention and control: a meta-analysis and systematic review. Acta Ophthalmol. 2017;95(6):551-566. doi:10.1111/aos.13403
https://pubmed.ncbi.nlm.nih.gov/28251836/ - Jin JX, Hua WJ, Jiang X, et al. Effect of outdoor activity on myopia onset and progression in school-aged children in northeast China: the Sujiatun Eye Care Study. BMC Ophthalmol. 2015;15:73. Published 2015 Jul 9. doi:10.1186/s12886-015-0052-9
https://pubmed.ncbi.nlm.nih.gov/26152123/ - Jiang X, Pardue MT, Mori K, et al. Violet light suppresses lens-induced myopia via neuropsin (OPN5) in mice. Proc Natl Acad Sci U S A. 2021;118(22):e2018840118. doi:10.1073/pnas.2018840118
https://pubmed.ncbi.nlm.nih.gov/34031241/ - Torii H, Kurihara T, Seko Y, et al. Violet Light Exposure Can Be a Preventive Strategy Against Myopia Progression. EBioMedicine. 2017;15:210-219. doi:10.1016/j.ebiom.2016.12.007
https://pubmed.ncbi.nlm.nih.gov/28063778/ - Ohno-Matsui K, Igarashi-Yokoi T, Migita Y, Yamakawa Y; ORANGE study investigators. Efficacy and Safety of Low-Concentration Atropine in Slowing Myopia Progression in Children in Japan: The Randomized, Double-Blind Phase II/III ORANGE Study. Ophthalmol Sci. 2025;6(1):100960. Published 2025 Oct 9. doi:10.1016/j.xops.2025.100960
https://pubmed.ncbi.nlm.nih.gov/41311414/ - Navarra P, Buzzonetti L, Amico V, Cro M, Federico B. A systematic review with meta-analysis on the efficacy of 0.01% atropine eyedrops in preventing myopia progression in worldwide children’s populations. Front Pharmacol. 2025;16:1497667. Published 2025 May 22. doi:10.3389/fphar.2025.1497667
https://pubmed.ncbi.nlm.nih.gov/40474980/ - Tang K, Si J, Wang X, Lu X, Bi H. Orthokeratology for Slowing Myopia Progression in Children: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Eye Contact Lens. 2023;49(9):404-410. doi:10.1097/ICL.0000000000001006
https://pubmed.ncbi.nlm.nih.gov/37284749/ - Phulke S, Kaushik S, Kaur S, Pandav SS. Steroid-induced Glaucoma: An Avoidable Irreversible Blindness. J Curr Glaucoma Pract. 2017;11(2):67-72. doi:10.5005/jp-journals-l0028-1226
https://pubmed.ncbi.nlm.nih.gov/28924342/ - Saeki H, Ohya Y, Furuta J, et al. English Version of Clinical Practice Guidelines for the Management of Atopic Dermatitis 2021. J Dermatol. 2022;49(10):e315-e375. doi:10.1111/1346-8138.16527
https://pubmed.ncbi.nlm.nih.gov/35996152/
