这是一场令人沮丧的情景 - 在一段时间内成功减慢了患者的近视进展，并准备审判撤回治疗。或者，也许更有可能 - 由于隐形眼镜不适，掉落或解决方案的过敏，或者简单的不合规性患者已停止治疗自己的协议。然后突然，近视进展的速度再次加速 - 近视反弹效应。这是什么时候发生的？你能避免它吗？你应该考虑在实践中做些什么？
What is a rebound effect?
A rebound effect described the sudden resurgence of a condition or problem, once treatment is withdrawn. Whilst myopia treatments are effective, there is concern that once treatment is stopped, the short sightedness can have an unprecedented, rapid change. When the concern is on the negative effects that myopic stretching on the retina, rapid growth may cause further damage. Read further as we explore the potentials of myopia control treatment rebound, and the consequences that has for your management plan and for your patient.
Atropine rebound effects
这是当下最热烈辩论的近视问题之一。让我们逐步一些当前的证据。
可以说是最着名的阿托品研究是用于治疗儿童近视（原子）系列的阿托品。在第一个（Atom-1）的研究中，346名儿童在1％的阿托品下降或安慰剂上开始进行近视。1The atropine was very effective, showing around 80% control of refraction and a halt in axial length growth (100% effectiveness) compared to the control group.
After this study, the children were followed for an additional 12 months with no intervention, and here's where the rebound effect was first noted. In this following year, the children who'd been treated with atropine in the prior two years progressed -1.14+0.80D in a year, while the children who'd not had atropine treatment in the first two years progressed -0.38+0.39D in that third year. This reduced the final 1% atropine treatment effect to only 0.25D difference in refraction and 0.23mm difference in axial length (about a 40% treatment effect). The results don't clearly state by how much the 'rebounding' eyes grew in mm in that third year, but comparing results of the two papers indicates the eyes treated with atropine grew around 0.30mm in that third year while the untreated eyes grew by around 0.18-0.20mm.2
In the ATOM-2; study, with two year follow up,3concentrations of 0.5%, 0.1% and 0.01% were investigated. In this case the results were concentration dependent, but there was no control group - as interestingly, the 0.01% was meant to be the control! What a plot twist that turned out to be! This study didn't look at rebound.
This was followed by the Five-Year Clinical Trial on Atropine for the Treatment of Myopia 2, or "ATOM-2 five year study", which followed these children after the initial two years, where treatment was ceased for a year. This allowed us for the first time to consider that whilst children had good control on atropine, those on higher concentrations rebounded faster: 68% of the 0.05% group progressed at least 0.5D in the year of cessation, compare to 59% of the 0.1% group and 24% of the 0.01% group.4These progressing children were all restarted on 0.01% atropine for another two years, with overall myopia progression and change in axial elongation being lowest in the 0.01% treated group (two years on, one year off, two years on) compared to those treated with 0.5% or 0.1% in the first two years then 0.01% in the last two years. The final difference was about 0.5D less myopia and 0.1mm less axial elongation in the 0.01%-throughout group compared to the other two groups.
This rebound is demonstrated in the graph below, which is Figure 6 from the open-access paper of the ATOM-2 five year study.4
Five Year Clinical Trial on Atropine for the Treatment of Myopia 2 (ATOM2), Chia et.al 2016
Findings from the ATOM1 and ATOM2 studies
What is a true rebound effect?
In the 2009 study on the effect of myopia progression after cessation of atropine the authors Tong et al.2comments that atropine has two actions - firstly a short term "reversible" action, that may cause the observed minor reduction in spherical refraction in the first few weeks, potentially due to the cycloplegic nature of atropine, especially at 1% concentration. The second, longer term action controls the ongoing refractive change. They suggested that the “rebound effect” isn’t really a push forward of the myopic growth, and rather a loss of that initial cycloplegic effect masking some of the refractive error.
This is an important consideration. If refractive error rebounded without an axial length change, then this short-term cycloplegic effect could be considered the explanation. However axial length seemed to grow faster in the 2009 ATOM-1 rebound study too, by around 0.1mm compared to the control group.1,2
We simply don't know any more than that, at this stage. There's no doubt that refractive control tends to be much greater in atropine studies than the axial length control,3-5which could be due to a cycloplegic effect on refraction.
你应该在实践中做些什么？Consider that abrupt cessation of stronger concentrations of atropine (0.1% or more) will likely cause a rebound effect.2,4Rebounds haven't yet been studied in the more frequently clinically prescribed concentrations of 0.05% and 0.025%. This is why, in practice, we'd consider a taper for any concentration. The World Health Organisation (WHO) recommends using a taper, even for 0.01% atropine, but doesn’t give suggested regimes.6A sensible option would be to treat like a very slow topical steroid taper. We give some suggestions for this in our blogWhen to prescribe atropine for myopia control.
Orthokeratology rebound effects
Pauline Cho和其他人调查了Orthokeokatology（OK）在一个题为题为Obeball伸长症（垫片）上停药的研究中的反弹。7在基线8-14岁的儿童已经在半年前持续了六个月，并投入单一视觉距离眼镜，而另一半继续磨损。在整个视觉眼镜中还有一个对照组。
In the first six months after OK discontinuation, there appeared to be an axial length rebound - the OKd (discontinued) group grew by 0.15mm compared to 0.08mm in the control and OKc (continued) groups. Then after six months, the OKd group commenced OK wear again, and all groups grew by a similar rate of around 0.06mm over another six months.
We would expect progression to decrease with time naturally, but this 'rebound' effect led to the conclusion that OK should not be ceased before age 14.
你应该在实践中做些什么？Cho suggests not stopping OrthoK until children are over 14, and in this case monitoring axial length for at least 6 months. OK lens wear can be resumed if rapid axial elongation is observed, as the myopia control effect will be achieved again.7In practice, OK discontinuation is probably unlikely once a child has developed good habits around lens wear, because of the benefits of the modality.
Other optical rebounds?
There's no evidence, simply due to a lack of studies, showing a rebound from dual focus or multifocal soft contact lens treatment for myopia control.
联合国published data on the MiSight study, presented at theInternational Myopia Conference in late 2019，描述了前三年后的研究的第二阶段，所有对照组儿童都切换到毛毛磨损。前述控制组展示了与整个毛毛相同的进展速度。这并没有真正向您提供反弹的任何数据;相反，对于垫垫的研究，即在没有治疗后开始近视治疗治疗的逆转，仍然导致对同龄人的儿童达到的比赛，这是对近年的近年来的近年来的近年来的相当效果。
When to stop myopia control treatments
We've written a whole blog on this for you, covering when myopia tends to naturally stop progressing, considering why you need to stop, and clinical consideration. Read more here onwhen to stop myopia control treatments.
About Cassandra
Cassandra Hainesis a clinical optometrist, researcher and writer with a background in policy and advocacy from Adelaide, Australia. She has a keen interest in children's vision and myopia control.
参考
- Chua WH. et al. (ATOM-1) Atropine for the Treatment of Childhood Myopia. Ophthalmology 2006;13:2285-2291.(link)
- Tong L. et al. Atropine for the Treatment of Childhood Myopia: Effect on Myopia Progression after Cessation of Atropine. Ophthalmology 2009;116:572-579,(link)
- Chia A. et al. Atropine for the Treatment of Childhood Myopia: Safety and Efficacy of 0.5%, 0.1%, and 0.01% Doses (Atropine for the Treatment of Myopia 2). Ophthalmology 2012;119:347-354,(link)
- Chia A, Lu QS. & Tan D. (ATOM-2) Five-Year Clinical Trial on Atropine for the Treatment of Myopia 2: Myopia Control with Atropine 0.01% Eyedrops. Ophthalmology 2016;123:391-399, (link)
- 山药JC。等等。（灯）低浓度阿托品用于近视进展研究：随机，双盲，安慰剂对照试验0.05％，0.025％和0.01％的近视控制中的阿托品滴眼液。2019年眼科; 126：113-124.(link)
- WHO. The Impact of Myopia and High Myopia (World Health Organisation with the University of New South Wales, Sydney, Australia, 2015)（关联）。
- Cho P, Cheung SW. Discontinuation of orthokeratology on eyeball elongation (DOEE). Cont Lens Anterior Eye. 2017;40:82-87.(link)
