Current Issue

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In this week’s issue

• Patients with treated phakic retinal tears undergoing cataract surgery face an increased risk for new retinal tears or detachments, particularly within the first postoperative year.
• PRP treatment for proliferative diabetic retinopathy stabilizes disease, but may exacerbate macular capillary nonperfusion, raising concerns for long-term outcomes.
• In the search for new prognosticators of MS disease status, ERG is likely not useful in monitoring or prognostication of MS.
• Myopic regression affects nearly half of patients within 18 months of LASIK or SMILE surgery, with preoperative spherical equivalent as the strongest predictor.

Too busy to read the lens? Listen to our weekly summary on your daily commute:https://creators.spotify.com/pod/show/lens-pod/episodes/The-Lens-Newsletter-Dec--4--2024-e2rr971

Ophthalmology

Retinal tears and detachments after cataract surgery in eyes with a history of treated phakic retinal tears

When cataracts clear, retinal risks may appear! Untreated retinal tears (RTs) pose a significant risk of progressing to retinal detachments (RDs). However, treatments like cryotherapy and laser photocoagulation have reduced this risk to less than 5%. This study retrospectively investigated the incidence, characteristics, and outcomes of RTs or RDs following cataract surgery in patients with a history of treated phakic retinal breaks. The goal was to enhance understanding of RD risk and improve patient care. Electronic medical records from 2012 to 2023 were analyzed to evaluate the incidence, risk factors, and outcomes of RTs and RDs after cataract surgery in patients with previously treated phakic RTs. Cases with prior RD or vitrectomy were excluded. Statistical methods, including logistic regression and Kaplan–Meier survival analysis, were used for data analysis. Among 12,109 phakic eyes treated for RTs with laser retinopexy or cryotherapy, 8.6% underwent cataract surgery during the follow-up period. Of these, 17.5% developed new RTs or RDs postoperatively (P = 0.020 for RTs; P = 0.100 for RDs). Significant risk factors for new RTs or RDs included younger age (P = 0.001), male sex (P = 0.009), shorter intervals between retinal treatment and cataract surgery (P = 0.015), myopia (P = 0.002), lattice degeneration (P = 0.010), and a history of RT or RD in the fellow eye (P = 0.027). Visual outcomes improved in cases of RT but declined following RD diagnosis, despite high rates of successful anatomic repair. The incidence of RTs and RDs after cataract surgery in patients with treated phakic retinal breaks is significantly higher than in the general population, with most events occurring within the first postoperative year. These findings underscore the importance of early postoperative monitoring and timely intervention to preserve visual outcomes.

JAMA Ophthalmology 

Macular capillary nonperfusion in stable laser-treated proliferative diabetic retinopathy

Fighting fire with fire? In proliferative diabetic retinopathy (PDR) treated with panretinal photocoagulation (PRP), vision loss has been linked to macular capillary nonperfusion (CNP)-associated ischemia or infarction. A prospective cohort study followed 63 participants with stable, laser-treated PDR in at least one eye, macular CNP, and a best-corrected visual acuity (BCVA) letter score of at least 54 over 12 months to evaluate changes in BCVA, low-luminance visual acuity (LLVA), and OCTA metrics. At baseline, mean BCVA and LLVA ETDRS letter scores were 77.52 (SD 8.0) and 68.33 (SD 8.9), respectively, improving slightly to 78.76 (SD 8.3) and 70.20 (SD 8.1) at 12 months. However, linear mixed-effects analysis revealed a deterioration in the foveal avascular zone (FAZ) area over 12 months, with a mean increase of 1.80% (95% CI 0.01%–3.63%; P = .05) at 6 months and 2.26% (95% CI 0.29%–4.26%; P = .03) from baseline. The findings indicate that FAZ area worsens over time in eyes with stable laser-treated PDR and macular CNP, suggesting a need for further research into longer-term effects.

IOVS

Ruling out ERG as a biomarker of MS progression

It’s electric! Multiple Sclerosis (MS) is an incurable, autoinflammatory, neurologic disease that affects roughly 2.9 million people worldwide. Previous studies have demonstrated abnormal retinal function in MS patients, specifically delayed electroretinogram (ERG) b-waves, indicative of bipolar cell dysfunction. This finding has led to interest in the use of ERG as a potential prognosticator of MS. However, these studies have mostly included MS patients with mild severity or those with a short duration of disease. This cross-sectional observational study examined ERGs of 56 MS patients with moderate to severe disease and 38 healthy controls. Full field ERGs were conducted on each patient and bipolar cell function was studied using dark-adapted (DA3.0) and light-adapted (LA3.0) b-wave peak times and amplitudes. Investigators studied the effect of expanded disability status scale (EDSS), disease duration, history of optic neuritis, or treatment status on ERG measurements. Researchers found that there was no effect of EDSS, disease duration, optic neuritis history, or treatment status on ERG peak b-wave times. They found no distinct differences in bipolar cell dysfunction in severe disease compared to documented findings in milder or earlier disease states, leading to the conclusion that ERG is unlikely to be a useful tool for grading MS severity. Ophthalmic biomarkers are a research topic of interest to many, as they are a lower cost and less invasive way to study systemic disease. In light of this, these negative findings are useful to rule out a hypothesis and inspire new ideas to assess MS disease status. 

Cornea

Comparing myopic regression in LASIK versus SMILE

We’re only moving forward -- or are we? Laser refractive surgery, while a popular solution for correcting myopia, is not immune to myopic regression, which can lead to patient dissatisfaction. Factors contributing to regression include preoperative spherical equivalent, age, intraocular pressure, optical zone diameter, and central corneal thickness. The primary hypothesis for myopic regression centers on corneal remodeling caused by epithelial hyperplasia and biomechanical changes from stromal tissue removal. Between January 2019 and July 2021, 1,026 eyes undergoing LASIK and 1070 eyes undergoing SMILE surgery were recruited, with 516 LASIK eyes and 528 SMILE eyes ultimately enrolled. Patients were monitored at 1 day, 1 week, and 1, 3, 6, 9, 12, and 18 months postoperatively. Myopic regression was defined as a refractive shift greater than 0.50 D at any follow-up visit. By 12 and 18 months, only 55.07% and 43.03% of LASIK patients, respectively, and 58.29% and 43.46% of SMILE patients, respectively, remained free from myopic regression. Preoperative spherical equivalent emerged as the strongest predictor of postoperative regression. While SMILE demonstrated a slightly lower regression rate than LASIK, the difference was not statistically significant (p = 0.11).

Collaborative Longitudinal Evaluation of Keratoconus (CLEK)

Did you know Steph Curry has keratoconus? Imagine how tough it would be for him if he couldn’t see the rim anymore. In the 2007 CLEK study, patients 1209 patients with keratoconus were enrolled to prospectively evaluate changes in vision, corneal status, corneal curvature, and vision-related quality of life (V-QoL) changes over time. 

Key Points:

• 53% of enrolled patients reported a history of atopy, 50% reported a history of vigorous eye rubbing
• Patients experienced a 2.03 letter (high-contrast) and 4.06 letter (low-contrast) reduction in BCVA at 7 years
• Of the 878 patients without corneal scarring at baseline, the 5-year incidence of scarring was 14% 
• 11 NEI-VFQ scales were measured, with almost all measurements showing modest decline in V-QoL over a 7-year period (increase in dependency being the most significant)

Overall, the CLEK study is a landmark study because it was a large-scale natural history study that provided clinicians with data on the natural progression of keratoconus. Furthermore, it highlighted that keratoconus is a debilitating disease, objectively measuring the patient-perceived significant impact it plays in progressively worsening quality of life.