Colder than the tip of the eyesburg. The multicenter Trial of Cryotherapy for Retinopathy of Prematurity was developed in the 1980s to provide a more evidence-based approach to the treatment of retinopathy of prematurity. More specifically, the study sought to determine the value and outcomes of peripheral ablative treatment (specifically cryotherapy) for the treatment of ROP.
Key Points
Overall, the CRYO-ROP was a landmark study for both the screening and treatment of ROP, even if the specific treatment has become a secondary one in the time since. The main findings of this study showcase a decreased incidence of blindness and retinal detachment, improved visual acuity outcomes, and improved structural outcomes in eyes treated with cryotherapy. A second-generation study, the ET-ROP, studied laser photocoagulation as ablative treatment, which has now become the paradigm for ROP management.
Is patience still a virtue when managing ROP? The most common cause of pediatric blindness in the United States is retinopathy of prematurity (ROP), a condition characterized by abnormal angiogenesis following incomplete retinal vascularization in premature infants. Surgical management of ROP involves cryotherapy or laser therapy to avascular retina – however prior to the ETROP study, standard of care involved waiting to intervene until risk of retinal detachment or macular folds reached ≥ 50% (“threshold” ROP). ETROP was a randomized control trial to determine whether early ablation for “prethreshold” ROP (risk ≥ 15%) would improve visual acuity and structural outcomes compared to conventional management.
Key Findings:
ETROP was a landmark study that established the current treatment guidelines for ROP, demonstrating the structural and visual benefits of early intervention for eyes with type 1 ROP. However even with early treatment, 65.4% of eyes still developed visual acuity worse than 20/40, indicating the fundamental limitations in ROP management.
Can injections alone curb ROP? Retinopathy of prematurity (ROP) is a neovascular retinal disorder and leading cause of childhood blindness, primarily in infants of low birth weight. At the time of BEAT-EOP, laser therapy was the gold standard for treatment of stage 3+ ROP. However, vascular endothelial growth factor (VEGF) inhibitors, including bevacizumab, were often used off-label, with purported benefits. This prospective, multicenter, randomized controlled clinical trial compared intravitreal bevacizumab monotherapy and conventional laser therapy on recurrence rates of ROP in infants with stage 3+ ROP who had zone I or II posterior disease. 143 infants, evaluated at 54 weeks’ postmenstrual age, were included in the primary outcome analyses.
Key Findings:
This landmark study demonstrated that intravitreal bevacizumab monotherapy provided a significant decrease in zone I disease recurrence in infants with stage 3+ ROP when compared with conventional laser therapy. Such findings dramatically altered the treatment protocol and outcomes for many infants with ROP.
Kids often dress up as pirates, but do they really want to keep their eye patches on after Halloween? Prior to this landmark study in 2002, the corrective treatment for amblyopia correction was almost exclusively patching. Still, concerns around compliance raised the question of whether medical penalization therapy (atropine) could be similarly effective. In this trial, children aged 3-7 with moderate amblyopia were randomized to be treated with either patching or 1% atropine in their non-amblyopic eye.
Key Points:
The importance of this study was showing that both patching and atropine are effective in treating moderate amblyopia in children ages 3-7, with patching improving VA more rapidly and atropine being easier to administer as well as cheaper.
Usually a quick patch doesn’t solve the real problem, but could it be enough in amblyopia? Evidence shows that patching improves amblyopia, however many have questioned this due to the lack of inclusion of an untreated control group. In this Amblyopia Treatment Study (ATS), 180 children ages 3-7 with moderate-severe amblyopia were randomized to be treated with either 2 hours of patching or spectacles alone (if required), after a 16-week period of refractive correction.
Key Points:
The ATS – patching versus correction study provided concrete evidence that patching the sound eye provides modest improvement in amblyopia in children ages 3-7.
A drop a day can keep the… glasses away? Myopia is the most common eye disorder in humans and is associated with multiple irreversible blinding conditions including retinal detachment. Prior to this study, atropine was described as an agent that could slow progression, but there had been no long-term, randomized control trials. ATOM 1 is a randomized control trial in which children aged 6-12 with refractive error between -1.00D and -6.00D were randomized to either 1% atropine sulfate or vehicle eye drops once nightly for two years.
Key Points:
This study was the first randomized control study to show slowing of myopia progression in children with atropine use. This study has limited extrapolation due to its limited study population (exclusively Asian children) and time course (two years). Additionally, there have been questions as to whether the effect lasted after stopping atropine, something that was examined in ATOM2 study.
How low can you go… with the dose of atropine in myopic children? Following the first ATOM1 study, which showed that 1% atropine could slow myopia progression, the 2012 ATOM2 study sought to determine what dosage provided the most benefit without the cost. In this study, 400 myopic children were randomized to treatment with atropine 0.01% (n=84), atropine 0.1% (n=155), or atropine 0.5% (n=161).
Key Points:
Overall, the ATOM2 study is a landmark study because it showed that atropine 0.01% was a safe and efficacious dose in children to decrease the progression of myopia while minimizing the visual side effects seen with higher doses.
Atropine can make you hot as a hare and red as a beet! But can also reduce myopia progression? High myopia is associated with excessive eyeball growth leading to sight-threatening complications down the road. Although concentration-dependent responses in myopia control were evident with higher-concentration atropine eye drops (ATOM study), the role of low-concentration atropine in myopia control was uncertain. This double-blinded, randomized control trial evaluated the efficacy and safety of atropine eye drops at 0.05%, 0.025%, and 0.01% compared with placebo over a 1-year period. 438 children, ages 4 to 12, with myopia of at least −1.0 diopter (D) and astigmatism of −2.5 D or less were included.
Key Points:
This landmark study demonstrated that low-concentration atropine eye drops reduced both spherical equivalent progression and axial length elongation along a concentration-dependent response, with 0.05% atropine eye drops being the most effective dose in reducing myopia progression.
Peekabo! Eye See You! The Infant Aphakic Treatment Study (IATS) sought to compare visual outcomes in infants (aged 1-6 months) with a unilateral congenital cataract following cataract extraction surgery and either intraocular lens (IOL) implantation or left aphakic with contact lens usage. Patients then received the same patching therapy and were followed up for up to 5 years.
Key Points:
The IATS showed that with regards to neutral visual acuity outcomes and increased postoperative complications and intraoperative additional procedures, it is better to leave babies who are operated on in the first 6 months of life aphakic and use a contact lens, with the plan to implant an IOL a few years later. A variety of reasons may account for these findings, including a less-traumatic surgery with fewer reoperations needed later in life and a better fitted IOL. Still, for patients whom placing contact lenses may be unreasonable, it is worthy to consider lOL placement weighed against the potential risks to avoid amblyopia.
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