Read more

April 01, 2021
10 min read
Save

Managing myopia in pediatric patients is not a one-answer solution

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com.

Patients with high myopia can be at risk for ocular pathology, so managing, slowing and treating myopia in pediatric patients with drugs, multifocal contact lenses and refractive surgery are necessary.

According to the American Academy of Ophthalmology, having myopia can increase chances of later development of ocular pathology, such as cataracts, glaucoma and retinal detachments.

Robert S. Gold, MD
Patients and their families need to understand the treatment burden of the drops before an atropine regimen is started, according to Robert S. Gold, MD.

Source: Robert S. Gold, MD

There are effective options to slow myopia in pediatric patients, but not every procedure is appropriate for every patient. Low-dose atropine, multifocal contact lenses, orthokeratology and refractive surgery all slow myopic progression to some degree, but these options need to be tailored to the patient.

“For the right child, using the correct procedure can improve substantially their quality of life,” Lawrence Tychsen, MD, pediatrics division chief at Washington University School of Medicine in St. Louis, said.

The best candidates for atropine treatment are those who present with significant progression of their myopic refractive error over 6 to 12 months, OSN Pediatrics/Strabismus Section Editor Robert S. Gold, MD, said.

Low-dose atropine can slow myopic progression, but it can be burdensome because it must be used for several years. Patients and their families need to understand the treatment burden of the drops before an atropine regimen is started, Gold said.

 Lawrence Tychsen, MD
Lawrence Tychsen

“Significant in my practice would be over 1 D of myopia progression in a year and the concern of the parents to want to try a treatment that might reduce the progression over the next several years. It has to be made clear to the parent and the patient that the treatment will need to be done over many years, depending on when started and often into the teenage years. You need a candidate who will be cooperative to have drops instilled for many years,” he said.

Two large clinical trials, Atropine for the Treatment of Childhood Myopia (ATOM) in 2006 and Atropine for the Treatment of Childhood Myopia: Safety and Efficacy of 0.5%, 0.1% and 0.01% Doses (ATOM 2) in 2012, showed the safety and effectiveness of the compounded drug in several concentrations to slow myopia in pediatric patients.

The 5-year ATOM 2 study demonstrated the safety of the eye drop with no serious adverse events but revealed higher doses could result in pupil dilation, loss of accommodation and near vision limits.

Data support three different concentrations — 0.01%, 0.025% and 0.05% — with no clear-cut rules for which to use, Amy K. Hutchinson, MD, director of pediatric ophthalmology at Emory Eye Center, said.

Recent studies have suggested the higher concentrations are more effective in slowing myopia progression and axial growth, but long-term outcomes, especially the risk for rebound myopia when the medication is ceased, are unknown, she said.

Amy K. Hutchinson, MD
Amy K. Hutchinson

The 0.01% concentration is what most ophthalmologists currently use, but the higher concentrations may gain popularity because data show they might be more effective in slowing myopia progression without significantly increasing the risks for side effects such as loss of accommodation and pupillary dilation, she said.

Several challenges exist with the use of atropine. Because atropine formulations are compounded, they can be difficult and costly to obtain. The drug requires more counseling for patients and their families, which can be a barrier to treatment, and obtaining the drug from a compounding pharmacy can be time consuming.

“Not all parents are interested in this for their children. The ones who are interested tend to be more highly engaged parents who are doing their own research on the treatment. But some parents don’t want to use a drop every day for an indefinite period of time, usually at least 2 years,” Hutchinson said.

The average patients treated with atropine are school-aged children between 5 and 9 years of age with typical myopia. Data have not shown atropine to be effective in children who become myopic early in life, she said.

Compliance is typically an issue with atropine, Gold said. After the initial documentation of myopic progression, a discussion on treatment options must take place. The years of treatment with atropine must be stressed to families, as well as the fact that nothing can be guaranteed when it comes to results.

Atropine has few side effects, including burning on instillation and rare allergic reactions, Gold said.

“Concerned parents often ask if there is anything that can be done to slow myopic progression and ask if LASIK can be done on their child. After telling them that LASIK is usually not done until after age 18, atropine is the usual treatment that is discussed,” he said.

Pediatric refractive surgery

Refractive surgery can be an effective solution for a small subgroup of children who cannot wear glasses, typically because of sensory issues, OSN Pediatrics/Strabismus Board Member Erin D. Stahl, MD, said.

Developmentally disabled children with bilateral high myopia who refuse to wear glasses can be good candidates for refractive surgery, depending on their overall ocular health, Stahl said. However, the subset of children who gain significant improvement in quality of life from refractive surgery is small.

Erin D. Stahl, MD
Erin D. Stahl

“I started my career with a fellowship in pediatric ophthalmology and refractive surgery. I thought I would be able to treat these children — unilateral high myopes with amblyopia and developmentally delayed children who would not wear glasses — with refractive surgery. After about 7 years, I stopped doing these procedures in unilateral high myopes because the surgery did not add to their quality of life,” Stahl said.

Tychsen performs surgery on special needs children who cannot or will not wear glasses. These children may be averse to wearing items on their face or have difficulty with control of head or eye movement.

“Rather than looking through the optical center of the lens, they’re looking through an eccentric portion of the lens that distorts vision. The typical child that I would operate on would be a child with extreme prematurity, developmental delays, cerebral palsy, Down syndrome or autism spectrum disorder,” he said.

Patients with behavioral issues, such as oppositional defiant disorder, who refuse to wear glasses are also candidates for pediatric refractive surgery.

Preop, postop difficulties

The tools and methods for pediatric refractive surgery are adapted from adult refractive surgery, but preoperative and postoperative measurements are more difficult to obtain. A highly trained support team of optometrists and nurse practitioners is necessary to ensure the success of pediatric refractive surgery.

“You need a great team to help manage these surgeries. The procedures are performed under brief general anesthesia. That’s a distinction from adult refractive surgery where everything is done while the patient is awake. In children, everything is done while they’re asleep,” Tychsen said.

Parents must be willing to adhere as best as they can to the postoperative regimen, which may include numerous drops and ointments, for their child to be eligible for surgery.

Children must also wear soft, clear protective goggles or a clear shield for several weeks postoperatively to prevent rubbing of the eyes. Additionally, about one in five children will require postoperative elbow restraints for several days so they learn to not rub their eyes, Tychsen said.

“Preoperative and postoperative exams differ from adult exams. These children will not sit at a slit lamp. You have to use a portable slit lamp and may have to gently restrain them on an exam table for a proper postoperative examination,” he said.

PRK and refractive lens exchange

The simplest and least invasive pediatric refractive surgery is excimer laser surgery, usually PRK over LASIK. All children, not just special needs children, rub their eyes and are prone to ocular trauma. With PRK, a potential contusion to the eye or eye rubbing will not pose a danger to postoperative visual outcomes, Tychsen said. The epithelium will heal with PRK despite the patient’s actions.

“However, if a child displaced a LASIK flap, that would be a significant and substantial adverse event that could permanently degrade vision,” he said.

Patients are treated bilaterally and under general anesthesia. The preoperative exam and laser surgery take about 15 minutes, and children are usually able to leave within an hour of the procedure, he said.

Tychsen said he treats up to 5 D of myopia with PRK. Pediatric patients have high regression rates, which can be as much as 0.5 D per year.

“That’s due to both corneal remodeling of the stroma and epithelium, as well as a slight increase in axial length with growth,” he said.

For eyes with more than 5 D of myopia, a phakic IOL is necessary. Tychsen’s lens of choice for children is the Visian toric ICL (STAAR Surgical). The eye must have a sufficient corneal diameter and anterior chamber depth to support an ICL, he said.

In children with higher astigmatism, an alternative phakic IOL is needed. Tychsen said he will implant an Artisan PMMA IOL (Ophtec), which offers correction of up to about 10 D of astigmatism.

A small subset of pediatric patients who are highly myopic but do not have sufficient corneal diameter or anterior chamber depth to support the safe implantation of a phakic IOL require a refractive lens exchange.

“You do a lensectomy, a vitrectomy and then implant a standard IOL depending on the axial length. In some children, the axial length is so long and axial myopia so substantial that they don’t need an IOL to end up plano,” Tychsen said.

If a postoperative issue is expected and an examination cannot be performed, a brief postoperative examination under anesthesia may be necessary to ensure the healing process is going well, he said.

For the right child, surgery can improve their vision and quality of life vastly.

“It can be life transforming for many children. In one surgical step, you improve their visual acuity an entire log unit, taking them from 20/200 down to near 20/20. From the range of a blur equivalent of legal blindness to normal uncorrected visual acuity,” he said.

Contact lens therapy

For children who are not good candidates for refractive surgery, contact lens therapy may slow myopic progression.

MiSight 1 day (CooperVision) is the first FDA-approved progressive multifocal contact lens indicated for children between the ages of 8 and 12 years. In a study published in Optometry and Vision Science of 144 children with myopia randomly assigned to either MiSight lenses or control lenses, progression of refractive error was significantly reduced in children treated with MiSight lenses.

There was an unadjusted change in spherical equivalent refraction of –0.73 D less in the MiSight group compared with the control group (about –0.51 D vs. about –1.24 D, respectively; P < .001).

Orthokeratology

A separate option is orthokeratology, specially designed and fitted contact lenses worn nightly to temporarily reshape the cornea to improve vision. According to the American Academy of Ophthalmology, FDA clinical trials have shown orthokeratology-approved lenses can help patients achieve 20/40 vision or better.

A 2019 study in Ophthalmology of published evidence of orthokeratology showed the therapy typically reduced axial elongation by approximately 50% over a 2-year study period. This leads to an average axial length change value of approximately 0.3 mm for orthokeratology patients compared with 0.6 mm for control patients, corresponding to a difference of refraction of approximately 0.5 D between the two groups. The study authors concluded the treatment may be effective in slowing myopia progression in children and adolescents but poses a risk for infection.

In 2008, the AAO issued an official statement, recommending a wide margin of safety be built into the therapy due to reports of vision-threatening complications, such as infectious keratitis. Corneal erosions and iritis were also reported, according to a 2017 update on orthokeratology published in Journal of Pediatric Ophthalmology and Strabismus. The update reported results from a 2016 case-control retrospective study of 37 cases of Acanthamoeba keratitis, which found 24% of cases were in orthokeratology lens wearers. The update reported orthokeratology was estimated to be implicated in approximately 19.1% to 38.8% of recent cases of infectious keratitis.

The increased infection risk from orthokeratology makes it a controversial option for myopic control, Hutchinson said.

“There’s a great deal of controversy around orthokeratology because there can be devastating complications in terms of infections. We don’t use orthokeratology to treat myopia progression at my institution,” she said.

Many cases presented in the available literature showed the lenses were not fit well or were worn for too long, and when complications arose, they were not addressed quickly, Stahl said.

“These children had bad infections. There was scarring, and they needed corneal transplants. That is the last thing any of us want,” she said.

But orthokeratology lenses can significantly improve a pediatric patient’s quality of life while they treat myopia progression. The lenses are not required to be worn during the day, so children can play sports, go swimming and do all of the activities they would normally do.

There are several types of myopia control, so a conversation is always necessary with the families. Orthokeratology does not have to be offered as a stand-alone therapy or as an end-all solution. Other options can be attempted first, either as stand-alone or combination solutions.

“You provide the family with information on all options available to them. You can start them with atropine, and if that doesn’t work, you can add something else. It’s a toolbox approach. Not one option is going to work with every single patient,” Stahl said.

Click here to read the Point/Counter to this Cover Story.