Prevention of Myopia progression
For most people with myopia, the condition has only refractive ramifications. But those with high myopia are at risk for ocular pathology. (High myopia has recently been defined as –5.0 D or worse.) Thus, the rising prevalence of myopia may mean an increasing number of high myopes who are at risk for developing associated serious eye diseases, ranging from choroidal neovascularization to glaucoma and retinal detachment.
Because of growing concern about pathological myopia, recent research studies focused on slowing progression of garden-variety myopia in children have garnered interest among ophthalmologists. Low-dose atropine (0.01%) has emerged as an effective approach, as highlighted by the ‘Atropine in the Treatment of Myopia studies’ (ATOM1 and ATOM2). Although ATOM enrolled Asian patients, studies are now underway involving other populations. A recent retrospective study in the United States included mostly Caucasian and Hispanic children.
Noting that other treatments to slow the progression of myopia, such as orthokeratology and soft contact lenses with peripheral defocus–modifying designs, may be inconvenient or have unwanted side effects, low-dose atropine therapy is described as a significant breakthrough. Prior to this, we had no straightforward option to offer families of children who were becoming increasingly myopic. Now we have an effective treatment that has few side effects and works for most children.
Low-dose atropine has minimal effects on pupil size, accommodation, and near vision. The average pupillary dilation in the ATOM2 study was 1 mm, noting that most patients receiving low-dose atropine have no need for bifocal eyeglasses or sunglasses. In addition, 0.01% atropine results in “minimal loss of accommodation of only about 4.0 D. Although there is always a risk for systemic side effects with any medication, these appear to be rare with 0.01% atropine use.
Whom and when to treat. The use of 0.01% atropine is indicated in children from 6 to 12 years of age who are at least –0.5 D myopic, and with a definite history of progression over the last few months—usually at least 0.5 D over the last 6 months. Although the medication hasn’t yet been tested in children over 12 years of age, he added that it would not be unreasonable to use it in teenagers if their myopia is still progressing.
It is also recommended to use low-dose atropine for children from 5 to 15 years of age. Younger children are more likely to become more myopic over time than older children are, so they are of greatest concern.
Very young children.
Axial myopia is rare in children under 5 years of age. It’s not clear that children in this very young age group have the same mechanism for myopia as occurs in older children, so not currently recommended in treating the very young with atropine. It is added that a refractive error of –1.0 D or more in a child under 5 years of age would be atypical and concerning, and it would lead him to first rule out other etiologies (such as anterior segment congenital malformation).
How to treat.
The treatment regimen requires patients or parents to administer 1 drop of 0.01% atropine, daily, in each eye. The time of administration is not very important. Nighttime administration was traditionally the standard with higher doses of the drug because the side effects of the medication (pupillary dilation, reduction of accommodation) are less bothersome while the patient is asleep. Some do better remembering to administer it in the morning, or when they see it in their lunch box.
Duration of treatment.
It is recommended that we should use atropine for at least 6 months to see if it is working, and if it is having good results—i.e., myopia progression is lessening—then continue for at least 1 year in total in the first instance. One could then stop treatment and, if myopia starts up again, restart for another 6 months or a year.
0.01% atropine is used to treat myopia in children either for 2 years or to 15 years of age, whichever is longer. If a child’s myopia increases when we stop the atropine, it is recommended that we place them back on it for a year at a time until the eye has stopped growing. The treatment has little effect on the child’s quality of life, aside from the challenges of administering eye drops to children, who generally don’t like water in their eyes. The parents should be prepared for their children to continue using the medication until they are 18 years old, and then wean off it—or to stop it sooner if they experience any problems.
What to expect.
In the first 6 months, the myopia may still progress—a finding that was also seen in the ATOM2 study. After 6 months, the progression should slow significantly to –0.50 D change, or less, per year. Low-dose atropine has slowed the rate of myopic progression in many patients by between 30% and 50%. And few patients have had complete arrest of their myopic progression.
Follow-up during treatment.
After starting a child on low-dose atropine, follow-up after 6 months is the earliest time at which to begin assessing treatment efficacy. However, children are evaluated after 3 months, to ensure they have no significant side effects.
Follow-up after stopping treatment.
When a child stops treatment, the initial follow-up is at 6 months, then again at 12 months. If there is no change in this period, then the child follows up in 1 year. If the child changes, we restart the drops and recheck in 6 months.