The most important ophthalmology research updates, delivered directly to you.
In this week’s issue:
The Lens Pod
The Lens Pod: This week, we are joined by Dr. Jimmy Hu of the New York Eye and Ear Infirmary, who shares with us what medical students should know before their first cornea clinic and OR. Find the episode on Spotify, Apple Podcasts, or our website. Happy listening!
Now you see it, now you don’t. There are multiple methods of measuring visual field progression and the most common tool is the Humphrey Field Analyzer. Many practices use the Swedish Interactive Testing Algorithm (SITA) Standard sequence which takes approximately 7 minutes per eye. Other practices use the SITA Fast (4 minutes per eye) or the SITA Faster (3 minutes per eye). In this retrospective longitudinal study of 421 patients, investigators sought to determine how visual field measurements (specifically mean deviation) differ between SITA Standard and SITA Faster in glaucomatous eyes of varying severities. In mild and suspect disease eyes, there were no significant differences in mean deviation between the Standard and Faster sequences. However, compared to the Standard sequence, the Faster sequence resulted in a 0.87 dB mean deviation improvement in moderate glaucomatous eyes and a 1.49 dB improvement in advanced glaucomatous eyes. As a result, transitioning to the Faster sequence may conceal some disease progression in moderate and advanced glaucoma.
Genomics research has a different take on fishing for compliments. Genetic mutations affecting the complement system have been associated with an increased risk of nonexudative age-related macular degeneration (AMD). Although the precise etiology of AMD remains unclear, the complement system has gained attention as a potential therapeutic target with clinical trials investigating recombinant protein supplementation. Relatively little is known about genetic associations in Early Onset Drusen Maculopathy (EODM), which presents similarly to AMD, with drusen and subsequent vision loss beginning at a younger age. In a case-control study comparing 89 patients with EODM to 91 patients with AMD, researchers explored the genotypic and phenotypic characteristics of EODM using 52 genetic variants associated with AMD. A genetic risk score calculated with these variants was lower in patients with EODM compared to AMD (1.03 vs 1.60; p = 0.002). This finding indicates that single nucleotide variants used to calculate the score may be less prevalent in patients with EODM. However, the odds of having EODM were higher in patients who had rare variants of the CFH gene (odds ratio 7.2; 95% CI 2.7-19.6; p < 0.01), suggesting that complement factor H mutations are associated with this disease. This association may have implications for genetic counseling and therapeutic approaches targeting the CFH gene or the factor H protein.
What is the most common white blood cell with multilobed nuclei and stainable cytoplasmic granules seen on a smear? Neutrophils; and we’re starting to learn more about their role in the pathogenesis of diabetic retinopathy (DR). Prolonged hyperglycemia resulting in chronic subclinical inflammation contributes to changes seen in DR, however researchers sought to define the role of inflammatory immune cells in this process. Neutrophils contribute to our innate immunity by killing pathogens and sounding the alarm for infection. In that process, they secrete enzymes such as proteases and elastases that can clear invaders but can damage our own cells (including the blood vessel endothelium). In the current study, the role of neutrophil elastase (NE) was investigated in the pathogenesis of DR. Diabetes was induced in NE-deficient mice, mice treated with NE inhibitors, or mice overexpressing human alpha-1 antitrypsin. Outcomes measured included retinal superoxide generation, inflammation, leukostasis, and capillary degeneration. In mice diabetic for either 2 or 8 months, genetic deletion or pharmacologic inhibition of NE resulted in significant reductions in diabetes-induced retinal capillary degeneration. Leukocyte mediated endothelial cytotoxicity, superoxide levels, and retinal inflammation were also found to be reduced through deletion/inhibition of NE. These findings provide novel insights into the role of neutrophils in DR and present a potential pharmacologic target for future treatments.
American Journal of Ophthalmology
If you thought popping on blue-light glasses would save your eyes from eighteen straight hours of Netflix, think again. There is very little data to support the use of blue-light glasses. To address this evidence gap, the authors conducted a double-masked randomized controlled trial to investigate if blue-blocking lenses are effective in alleviating ocular symptoms associated with computer use. Objective and subjective eye strain measures did not differ based on advocacy type (positive or negative) or spectacle intervention type (blue-blocking or clear lens). Providers should use this information to judiciously counsel patients on the merits, especially the cost-benefits, of utilizing blue-light blocking glasses.
This may hurt. Surgeries in oculoplastics can be more invasive than in many other subspecialties in ophthalmology. Previous studies have found that oculoplastic surgeons have a higher opioid prescribing rate (16.5%) than general ophthalmologists (4%), but no studies have focused on prescription rates of of extended release/long-acting (ER/LA) opioids by oculoplastic surgeons. These medications are more commonly used for chronic pain, cancer, or hospice patients. The American Board of Medical Specialties has stated that there is no role for ER/LA opioids in ophthalmology. This was a retrospective observational cohort study that utilized the Medicare Part D database to analyze ER/LA opioid prescription patterns by 142 oculoplastic surgeons from 2013 to 2017. ER/LA opioids were prescribed by 10.6% of American Society of Ophthalmic Plastics and Reconstructive Surgery (ASOPRS) members and 19.6% of non-ASOPRS members. Non-ASOPRS oculoplastic surgeons prescribed 23.5% more ER/LA opioids than ASOPRS members. Over the study period, the number of prescribers and ER/LA prescriptions decreased, but the mean number of ER/LA opioids per prescriber increased. These results give further insight into opioid prescribing patterns among oculoplastic surgeons, but the authors recommended that these surgeons should defer ER/LA opioid prescription to chronic pain specialists.
How does visual field damage in glaucoma patients affect their risk for falls? It is well known that gait dysfunction is a predictor for fall risk and functional decline in older populations. While studies have shown that diabetes, dementia, and heart failure are associated with an increased prevalence of gait dysfunction, the relationship between visual impairment and gait is not well-established. This single-center prospective cohort study investigated the relationship between fall rates and glaucoma severity in 241 participants over a 3-year period. Results indicate that greater levels of visual field damage are significantly associated with a faster decline in walking speeds (i.e. stride velocity and cadence) over time. These findings are among the first to demonstrate the decline in functional trajectory in those with severe glaucoma. Further, the results of this study can be extrapolated to other ophthalmic conditions which affect visual acuity and field, including cataracts and ptosis.
A 40-year-old man presents to Ophthalmology clinic with concern for visually significant glare while driving at night. He has also noticed a change in the color of his right eye over the last year. He denies symptoms of eye pain, redness, or discharge. The unaffected iris appears brown with no color irregularity. Significant features of the appearance and slit lamp exam of the right eye are shown in the images below. These findings are absent in the left eye. What is the most likely diagnosis?
A. Posner-Schlossman Syndrome
B. Congenital heterochromia
C. Fuch’s Heterochromic Iridocyclitis
D. Waardenburg’s Syndrome
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