When ortho-k alone isn't enough: adding alternate-day atropine for fast progressors

A common question in myopia clinics: a child has been wearing orthokeratology (ortho-k) lenses overnight, the lenses fit well, and yet the eye is still growing faster than anyone would like. What next? A randomised study published in Translational Vision Science & Technology (2026) tested one option, adding 0.01% atropine eye drops every second night. This post is based on the full text.

What the trial did

The study was run at a single eye hospital in Qingdao, China. It enrolled 105 children aged 8 to 12 years with myopia between -0.75 and -5.00 dioptres. Every child had already worn a small treatment zone ortho-k lens for at least six months, and every child's eye had lengthened by 0.20 mm or more in that time. The trial therefore recruited only children responding poorly to ortho-k alone.

The lenses used a back optic zone of 5.6 mm rather than the conventional 6.2 mm, a design intended to place more myopic defocus within the pupil. Children were then randomly assigned to one of two groups for 12 months:

• Ortho-k plus atropine: the same lenses, plus 0.01% atropine on alternate days in the early evening.
• Ortho-k alone: the same lenses with no drops.

Axial length, the front-to-back length of the eye, was measured by optical biometry every three months. For background, see our review of the evidence for low-dose atropine.

What it found

Ninety-four children finished the year: 46 in the combination group and 48 in the ortho-k group. Six were lost from the combination group and five withdrew from the ortho-k group.

Axial elongation from randomisation was:

• At 3 months: 0.03 ± 0.06 mm with the combination versus 0.09 ± 0.04 mm with ortho-k alone.
• At 6 months: 0.09 ± 0.08 mm versus 0.18 ± 0.07 mm.
• At 12 months: 0.20 ± 0.12 mm versus 0.33 ± 0.09 mm (all P < 0.05).

The authors describe these as relative reductions of 66.7%, 50.0% and 39.4%. A P-value is the probability of seeing a difference this large if the treatments were really equal; below 0.05 is the usual threshold for "unlikely to be chance". The paper does not report 95% confidence intervals, the range within which the true average difference plausibly lies, so the precision of the estimate is harder to judge than it should be.

The effect faded over the year

The added benefit was not constant. In the first six months the combination group grew 0.09 ± 0.08 mm against 0.18 ± 0.07 mm (P = 0.031). In the second six months the figures were 0.11 ± 0.08 mm against 0.16 ± 0.06 mm (P = 0.040). The relative reduction fell from 50.0% to 31.3%. That is a reason not to extrapolate a first-year result to later years.

Why the before-and-after figure is the weaker one

The paper also reports that children in the combination group grew 0.24 ± 0.08 mm in the six months before atropine and 0.09 ± 0.08 mm in the six months after, a 62.5% reduction. This number deserves caution. Children were selected because they had an unusually fast six months. A group picked for an extreme value tends to drift back towards average on the next measurement whatever is done. The comparison with the randomised ortho-k group is the more reliable estimate, and it is smaller.

Pupils, optics and side effects

Pupil diameter was larger with atropine: 3.79 ± 0.68 mm versus 2.95 ± 0.53 mm at three months. Within the combination group, older age, larger pupils and greater pupil-zone defocus were each associated with less eye growth over the year. These are associations in 46 children, not tested mechanisms.

Two children (4.35%) in the combination group reported light sensitivity, which settled within a week. Halos and glare were reported more often with the combination (P = 0.001 and P = 0.004), although overall visual quality scores did not differ significantly (P = 0.258). No serious adverse events were reported.

Limitations of this evidence

• No masking and no placebo drop. The paper describes no masking of children, parents or examiners, and the comparison group used no dummy drops. All measurements were taken by one examiner. Axial length is an objective measure, but lens wear and symptom reports can be influenced by knowing the allocation.
• Selected fast progressors. Results apply to children still progressing quickly on this lens design, not to children starting ortho-k or those already doing well.
• Completers only. Eleven of 105 children were not analysed, and how they fared is unknown.
• Short and small. One year, one centre, 94 children.
• Thin reporting. The randomisation method and any sample size calculation are not described, and confidence intervals are absent.
• Unanswered comparisons. Alternate-day dosing was not compared with nightly dosing, nor this lens with a conventional design.
• No stopping data. Nothing is known about what happens when the drops are withdrawn. Our post on rebound after myopia treatment explains why that matters.
• Funding and conflicts. We could not verify the funding and disclosure statements from the text we retrieved.

What we do with this in practice

This trial supports a reasonable clinical idea: when axial length is still climbing on ortho-k, adding low-dose atropine was associated with slower growth over the following year, at the cost of somewhat more glare and halos. It does not show that the benefit holds beyond 12 months, or that every second night is as good as every night. Two sibling posts this week look at related dosing questions: whether higher atropine concentrations keep adding benefit and a stepwise approach to increasing the dose.

Atropine is a prescription medicine, and whether it or a particular lens design is available and suitable for your child is something to discuss with your optometrist. In Hamilton, the optometrist team at Rose Optometry measures axial length at review visits so that decisions rest on eye growth and not on refraction alone; more detail is on the Rose Optometry myopia control page. The team also offers a free Myopia Chat. The optometrists at Rose Optometry are Anjali Hira, Emilie Lawson, Jacqueline Rowe, Jagrut Lallu, Jason Shen, Jessica Wood and Stella Wong, and myopia management is part of their clinical practice.

Whatever is added, careful lens hygiene remains the foundation of safe overnight wear. Our ortho-k lens care guide covers the routine, and MeniCare Plus, a solution for rigid and ortho-k lenses, is available from the Rose Optometry online store. The trial did not test any lens care product.

Jagrut Lallu — BOptom (Hons), MSc Specialty Lenses (Hons), FIAOMC. Therapeutic Optometrist & Contact Lens Specialist. Founder, New Zealand Eye Research Centre; Partner, Rose Optometry; WCO Asia-Pacific Myopia Ambassador; International Myopia Institute NZ Ambassador; Clinical Senior Lecturer, Deakin School of Optometry; Honorary Teaching Fellow, University of Auckland.

Reference

• Xu M, Jing L, Zhao L, Xiu Y, Du X. Combined Small Treatment Zone Orthokeratology and Alternate-Day 0.01% Atropine for Axial Elongation Control in Rapidly Progressing Myopic Children. Translational Vision Science & Technology. 2026;15(9):13. PMID 42770659. https://doi.org/10.1167/tvst.15.9.13