Treating ROP: Laser associated with high success rate for retinopathy of prematurity
Laser photocoagulation is a time-tested, well-defined, and effective treatment for retinopathy of prematurity (ROP) with requirements for follow-up that are much more manageable compared with anti-vascular endothelial growth factor (anti-VEGF) therapy, argued David K. Wallace, MD, MPH.
Reviewed by David K. Wallace, MD, MPH
Laser photocoagulation is a time-tested, well-defined, and effective treatment for retinopathy of prematurity (ROP) with requirements for follow-up that are much more manageable compared with anti-vascular endothelial growth factor (anti-VEGF) therapy, argued David K. Wallace, MD, MPH.
Read the other side of the debate: Treating ROP: Substantial benefits make anti-VEGF preferred for Zone I disease
Dr. Wallace outlined the reasons why a physician might choose laser over anti-VEGF injections for treating ROP.
“There are situations where anti-VEGF injections may be better than laser treatment, such as in eyes with Zone I disease,” said Dr. Wallace, professor of ophthalmology and pediatrics, Duke University, Durham, NC. “In addition, we might use both treatments in eyes with Zone I disease, adding laser after anti-VEGF therapy if vascularization stalls and worrisome signs develop. However, there are cases where laser may be a better choice, and there is still a lot we need to know about anti-VEGF therapy for ROP.”
Presenting a “top-10 list” of reasons to consider laser for ROP rather than anti-VEGF therapy, Dr. Wallace said the absence of systemic side effects with laser versus the yet-to-be-defined systemic safety of anti-VEGF therapy represents the most compelling argument.
“We know that anti-VEGF drugs enter the blood and that serum VEGF levels are reduced after intravitreal anti-VEGF injection,” Dr. Wallace explained. “We don’t know how reductions in circulating VEGF affect developing organs that rely on VEGF, but a recent study analyzing data from the Canadian registry of premature infants found significantly worse motor development in preterm babies treated with bevacizumab (Avastin, Genentech) compared with those treated with laser [Pediatrics. 2016 Apr;137(4)].”
Follow-up favors laser
Easier follow-up is another big advantage of treating ROP with laser. Examinations are done weekly for about two to four weeks. If there are no concerns, infants are seen again a month later, and then the visit frequency can decrease to every three to six months.
“It can be very difficult to visualize the peripheral retina when trying to examine a big, strong baby,” Dr. Wallace said. “There are many fewer examinations needed after laser treatment compared with anti-VEGF therapy. The follow-up schedule needed after anti-VEGF therapy is much more rigorous and can also be difficult for many families to manage.”
High success rate with laser
Dr. Wallace pointed out that laser has a high success rate for treating ROP. Among eyes treated at high-risk prethreshold in the Early Treatment of Retinopathy of Prematurity Study, rates of unfavorable visual acuity outcome and unfavorable retinal structure at the 9-month endpoint were 14.5% and 9.1%, respectively [Arch Ophthalmol. 2012;130:719.
“Once ROP regresses after laser treatment, late recurrence is very unusual,” Dr. Wallace added.
Laser treatment can be performed with just sedation in many cases rather than under general anesthesia.
“The laser treatment can sometimes be done with just 500 spots in a procedure that takes 20 to 30 minutes per eye,” Dr. Wallace said. “There is also no risk of endophthalmitis with laser treatment. Endophthalmitis after intravitreal anti-VEGF injection is rare, but it is a devastating complication if it occurs.”
Visual acuity and macular development
In addition, the long-term effects of anti-VEGF therapy on visual acuity and macular development are still unknown.
“We think there may be an advantage for anti-VEGF therapy,” Dr. Wallace said. “But in a small study by Lepore et al. vascular abnormalities developed in all eyes treated with bevacizumab compared with a minority of laser-treated eyes [Ophthalmology. 2014;121:2212-2219]. The long-term visual implications of these findings are unknown.”
He also noted that although there may be better vascularization into the periphery after anti-VEGF therapy compared with laser, vascularization sometimes does not progress far in bevacizumab-treated eyes. It also is unknown whether better peripheral vascularization leads to better peripheral visual fields.
“It is enticing to think that it could, and I look forward to seeing supporting data,” Dr. Wallace said.
The best anti-VEGF drug and appropriate dosage for treating ROP are also yet to be defined.
“The Pediatric Eye Disease Investigator Group conducted a phase I dosing study to begin to assess injecting a bevacizumab dose for treating ROP that is lower than the dose currently used,” Dr. Wallace said. “The study found that a dosage as low as 0.031 mg, or 5% of the BEAT-ROP dosage, was effective in all 9 eyes treated.”
David K Wallace, MD, MPH
This article is based on a presentation given by Dr. Wallace at the Pediatric Ophthalmology Subspecialty Day, held prior to the 2016 American Academy of Ophthalmology meeting. Dr. Wallace receives grant support from the National Eye Institute. He has no other relevant financial interests to disclose.
