Copy

March 1, 2023


The most important ophthalmology research updates, delivered directly to you.
Too busy to read the lens? Listen to our weekly summary on your daily commute here

In this week's issue
  • Vitamin D supplementation in older adults that live in a region with low vitamin D deficiency did not reduce need for cataract surgery compared to placebo.
  • Prevalence of myopia decreased after home isolation ended and returned to pre-pandemic levels in a cross-sectional study of children in China.
  • Retrospective study identifies risk factors for blindness at first presentation of glaucoma including low income, African-American race, and diabetes history.
  • Rho kinase inhibitor AR-12286 was effective at reducing IOP in a mouse model of steroid-induced ocular hypertension.

The tea on vitamin D 

Ophthalmology

Vitamin D supplements may not be as protective against cataracts as we think. Vitamin D deficiency has been linked to higher incidence of oxidative stress and inflammation in the lens, suggesting there may be an opportunity for vitamin D supplementation to reduce the incidence of cataracts. Although observational studies seem to support this theory, the first randomized controlled trial to assess for a causal relationship found no significant risk reduction. 19,925 Australian men and women aged 60-84 were randomly assigned to take either 60,000 IU of vitamin D3 or a placebo orally once per month for five years. The primary outcome for this analysis was surgical treatment for cataract. More than 80% of participants in both study groups reported adherence to study protocols. Overall, 18.5% (n=1841) of those in the vitamin D group and 18.3% (n=1827) of those in the placebo group underwent cataract surgery over a median follow-up of five years. There was no significant difference in the incidence proportion of cataract between the two groups (HR=1.02, 95% CI, 0.95-1.09). These findings do not support routine vitamin D supplementation to prevent cataract formation in populations with a low prevalence of vitamin D deficiency. Future research is necessary to assess the effect of vitamin D supplementation on cataract incidence in regions and populations with higher vitamin D deficiency. 

COVID-19 isolation of children in China and the prevalence of myopia

JAMA Ophthalmology

Did too much time at home during the pandemic impair children’s vision? Studies have found ocular development in children may be tied to their environment. One article noted an increased prevalence of myopia in children during home confinement in 2020 due to the COVID-19 pandemic. The goal of this study was to determine whether refractive changes in children between 6 to 8 years of age persisted after isolation ended in 2021. A cross-sectional study was performed for 6 to13 year old children in China, who participated in 8 school-based photoscreenings from 2015 to 2021. From 2020 to 2021, there was a statistically significant increase in mean differences of spherical equivalent refraction (SER) in children who were 6 (0.42 diopters [D]), 7 (0.41 D), and 8 years old (0.33 D). The prevalence of myopia in 2021 was comparable to 2019 levels for every age group (6-year old’s: 7.9% vs 5.7%; 7-year old’s: 13.9% vs 13.6%; 8-year old’s: 29.5% vs 26.2%). Overall, the study found the prevalence of myopia declined after home isolation ended and mean SER reverted back to pre-pandemic levels indicating that environment has a role to play in the refractive plasticity of children.

Who comes to clinic already blind from glaucoma?

American Journal of Ophthalmology

Time to put HIGH PRESSURE on blindness from glaucoma. Glaucoma is a progressive eye disease that impacts the optic nerve. It is the leading cause of irreversible blindness worldwide. Early diagnosis and treatment of glaucoma are important in preventing blindness as the disease often remains asymptomatic until late stages. It is important to understand risk factors that influence a patient being blind on the first presentation so blindness can be prevented. This retrospective cross-sectional study included 3,753 glaucoma patients with 192 (5%) patients presenting with legal blindness at first visit. Inclusion criteria included a minimum of 18 years of age and blindness defined using the United States Social Security Administration’s definition of legal blindness. The blind cohort had a greater proportion of African American/Black patients (65% vs. 43%) and a lower average income than the cohort not presenting blind. The blind cohort had more patients with a history of diabetes (18% vs. 9%) and a higher mean average IOP (19.9 mmHg vs. 18.0 mmHg). In the multivariate models, higher IOP and a history of diabetes were significant predictors of blindness for glaucoma types excluding primary open-angle glaucoma (POAG). All in all, certain clinical, demographic, and socioeconomic variables can impact presentation of blindness from glaucoma. Thus, certain interventions such as disease education in disadvantaged communities may help prevent blindness from glaucoma.

ROCK-inh around the clock with AR-12286

IOVS

This new Rho kinase inhibitor may be effective against steroid-induced ocular hypertension (SIOH). Chronic steroid use may cause intraocular pressure (IOP) elevation, a major risk factor for developing glaucoma. A mouse model of SIOH was used to test how well the Rho kinase (ROCK) inhibitor AR-12286 combats this change. 56 animals were randomized to one of four eye drop treatment groups: saline, dexamethasone (DEX), DEX+AR-12286, and DEX-discontinuation. IOP and microstructural changes in trabecular outflow tracts were analyzed over several weeks. Topical AR-12286 decreased IOP in SIOH mouse eyes within one week by increasing effective filtration area in the trabecular meshwork. Even when coupled with continuous DEX, AR-12286 administration outperformed DEX-discontinuation in treating SIOH. This study suggests the utility of this new drug against ocular hypertension for patients who are dependent on chronic steroid regimen.

Glaucoma

The beauty of asymmetry - better IOPs!

Journal of Glaucoma

(Pseudo)exfoliate early and (pseudo)exfoliate often. Capsular pseudoexfoliation (PXF) may lead to a significant increase in several intraoperative complications during and after cataract surgery (including glaucoma exacerbation from high intraocular pressure (IOP)). Lensectomy in patients presenting in an early phase of the disease course (asymmetric PXF indicating less progression) has been theorized to reduce these complications. In this retrospective, comparative study, researchers assessed whether there was a significant difference in outcomes for patients with asymmetric PXF versus symmetric PXF undergoing intraocular lens implantation more than 5 years postoperatively. Of 102 symmetric and 59 asymmetric cases, intraocular pressure (IOP) was found to be decreased only in the asymmetric group (P=0.004) with a notable reduction medication number in both eyes (P<0.001). Additionally, intraoperative complications, including late intraocular lens dislocation, were all associated with the symmetric group (P=0.03). These results suggest that lensectomy in patients with PXF in its asymmetric presentation results in more effective and safe long-term results.

Lens Landmarks
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 Points:
  • There was significant reduction in rates of ROP recurrence in infants in the bevacizumab group (6 of 140 eyes, 4%) versus infants in the laser-therapy group (32 of 146 eyes, 22%)
  • When segmenting by zone, a significant treatment effect was found for zone I retinopathy of prematurity (P = 0.003) but not for zone II disease (P = 0.27)
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.

Question of the Week
A 6 year old child presents for his first eye exam with visual acuity of OD 20/80, OS 20/40. Cycloplegic manifest retraction demonstrates OD -4.00, OS -1.50.
 All of the following are appropriate in management of this patient except:

A. Full spectacle correction
B. Patching
C. Atropine 0.05%
D. Contact lens fitting


 
Keep scrolling for answer or click here

Helpful Links
Quiz Answer: D
Quiz Answer Explained
Twitter Twitter
Website Website
Share with a friend Share with a friend
Copyright © 2023 The Lens Newsletter LLC, All rights reserved.