A Cochrane review, which is a systematic review of the studies and trials that looked at various methods to reduce the progression of myopia in children was published in 2018. Cochrane reviews are respected for their thoroughness and wide-ranging review of studies for treatments and are used to guide evidence-based practice.
In this review, Cochrane researchers found:
- 41 studies of treatments to slow myopia progression
- These studies included a total of 6772 children
The review found that the following treatments may slow the progression of myopia, compared with wearing ordinary spectacles:
- Eye drops, antimuscarinic drugs such as atropine, pirenzepine gel, and cyclopentolate (moderate-certainty evidence).
- Multifocal spectacles (either bifocal or progressive addition lenses) (moderate-certainty evidence).
- Bifocal soft contact lenses (low-certainty evidence).
- Orthokeratology contact lenses (moderate-certainty evidence).
- Combinations of eye drops and multifocal spectacles (moderate-certainty evidence).
The review found that the following treatments may have a small effect, or no effect, on myopia progression.
- Spherical aberration soft contact lenses (low-certainty evidence).
- Systematic adenosine antagonists (moderate-certainty evidence).
The review found the following may INCREASE the chance of progression:
- Children who wear undercorrected spectacles may have an increased chance of myopia progression compared with children who wear fully corrected spectacles (low-certainty evidence).
What is the response rate of Atropine eyedrops?
First, it is important to remember that once there is myopia, we cannot reverse the myopia. With each year, a child’s myopia will increase as the eye grows until the teenage years when it will start to stablise:
- The rate of progression is estimated to be around −1 D (or 100 degrees) per year in Asians and around −0.5 D (or 50 degrees) per year in Caucasians.
We may consider starting Atropine when the progression is more that -1.5D (or 150 degrees) per year.
When we look at the response rate of Atropine, we can turn to a Singapore study called ATOM 2 which stands for Atropine for the Treatment of Myopia 2 Study. In ATOM 2, researchers found that:
- Low-dose (0.01%) atropine for periods up to 5 years is a clinical viable treatment of myopia with the best sustained effect on slowing myopia progression.
- Atropine 0.01% slowed myopia progression by 50%
- Non-responders were low: 3% of children in the 0.01% group continued to have myopia progression ≥−1.5 D (more than 150 degrees) over the initial 2-year of active treatment.
What are the side-effects of Atropine eyedrops?
The side-effects of atropine eyedrops display a dose-dependent response. This means that higher concentrations have more side-effects the lower concentrations. The concentrations of atropine eyedrops come in: 1%, 0.5%, 0.1%, 0.05%, 0.025%, and 0.01%.
The most frequent eye side effects with atropine eye drops include
- Photophobia: sensitivity to bright light,
- Blurriness of near vision, and
- Local allergic response such as redness, swelling or itching of the eyes.
Side-effects affecting the body systemically are very rare and include:
- dry mouth,
- face flush,
- headache,
- increased blood pressure,
- constipation, difficulty in urination, and
- central nervous system disturbances
WHAT IS AMBYOPIA (OR LAZY EYE)?
A child’s vision system develops in the first few years of life and continues to do so until about 8 years of age.
- During this time, the brain and the eye are learning to work together.
- It is important during this time that the brain receives sharp images from the eye.
Amblyopia is when vision in one or both eyes does not develop properly during childhood. It is sometimes called lazy eye.
- Up to 3 out of 100 children have it.
- The good news is that early treatment works well and usually prevents long-term vision problems.
- It is therefore important to identify causes of lazy eye early and to correct them early.
- This needs to be done before 8 years of age, otherwise, lazy eye may become permanent.
What are the causes of amyblyopia?
Strabismus or Squint
Strabismus is when the eyes are not aligned properly so they appear to point in two different directions.
- One eye may be looking straight ahead while the other is turned in a different direction. Either in, out, up or down.
- To avoid double vision, the child’s brain may ignore the image from the eye that is not looking straight ahead.
- When this happen: that eye may become “lazy” and not develop normally.
Refractive errors
A refractive error is when the eye cannot focus an image clearly without the help of glasses. There are different types of refractive error:
- Shortsightedness, longsightedness or astigmatism
- Lazy eye can occur in 2 situations:
- Either due to undetected refractive error so that the child does not have glasses and has blur vision for some time
- One eye has much worse refractive error than the other eye. Usually a difference of more than “200 degrees” difference
- In both these situations the eye can “turn off” and vision will not develop properly
- If this is not corrected before 8 years’ of age, it can become permanent
- When this happens, even if you make glasses, the child will not be able to see perfectly and will have some blurring of vision, regardless of what power lenses you use.
Media opacity: Cloudiness in the normally clear parts of the eye
The 2 parts of the eye responsible for focusing light are the cornea and the lens.
In some children, either the cornea or the lens can become cloudy and cause less light to be able to reach the back of the eye.
