The Association Between Metformin Use and New-Onset ICD Coding of Geographic Atrophy.

Purpose: Metformin has been suggested to protect against the development of age-related macular degeneration (AMD) in multiple observational studies. However, the association between metformin and geographic atrophy (GA), a debilitating subtype of AMD, has not been analyzed. Methods: We conducted a case-control study of patients ages 60 years and older with new-onset International Classification of Diseases (ICD) coding of GA in the Merative MarketScan Commercial and Medicare Databases between 2017 and 2021. Cases were matched with propensity scores estimated by age, region, hypertension, and Charlson Comorbidity Index to a control without GA of the same year. Exposure to metformin was assessed for cases and controls in the year prior to their index visit. Conditional multivariable logistic regression, adjusting for AMD risk factors, was used to calculate odd ratios and 95% confidence intervals (CIs). This study design and analysis were repeated in a sample of patients without diabetes. Results: In the full sample, we identified 10,505 cases with GA and 10,502 matched controls without GA. In total, 1149 (10.9%) cases and 1277 (12.2%) controls were exposed to metformin, and in multivariable regression, metformin decreased the odds of new-onset ICD coding of GA by 12% (95% CI, 0.79-0.99). In the sample of patients without diabetes, we identified 7611 cases with GA and 7608 matched controls without GA. Twenty-nine (0.4%) cases and 63 (0.8%) controls were exposed to metformin, and in multivariable regression, metformin decreased the odds of new-onset ICD coding of GA by 47% (95% CI, 0.33-0.83). Conclusions: Metformin may hold promise as a noninvasive, alternative agent to prevent the development of GA. This finding is notable due to shortcomings in recently approved therapeutics for GA and metformin's overall ease of use and few adverse effects. Additional studies are required to explore our findings further and motivate a clinical trial.

FULL-THICKNESS MACULAR HOLE CLOSURE WITH TOPICAL MEDICAL THERAPY.

PURPOSE: To examine the efficacy and clinical characteristics of successful full-thickness macular hole closure with topical therapy. METHODS: Retrospective case series of full-thickness macular holes managed by a single retinal physician (DS) diagnosed and treated from 2017 to 22. RESULTS: Of 168 patients with full-thickness macular holes, 71 patients were started on steroid, carbonic anhydrase inhibitor, and nonsteroidal antiinflammatory (NSAID) drops. 49 patients (mean 67 years, 59% women) were included in the analysis, and 22 patients were excluded for poor follow-up. In total, 7/49 were secondary post-PPV holes and 42/49 were idiopathic. In addition, 18/49 eyes (36.7%) achieved closure on topical therapy, of which 13 were idiopathic. Hole size was directly correlated with odds of closure: for every 10 µm decrease in size and odds of closure increased by 1.2× ( P = 0.001, CI 1.1-1.4). Average time to closure was 107.2 days (range 20-512 days) and was not correlated with hole size ( P = 0.217, CI -0.478 to +1.938). The presence of VMT was found to be inversely related to successful closure (OR 6.1, P = 0.029, CI 1.2-31.3). There was no significant difference in final best-corrected visual acuity for eyes undergoing primary pars plana vitrectomy versus those trialing drops before undergoing pars plana vitrectomy ( P = 0.318, CI -0.094 to +0.112). CONCLUSION: In the first study to date to report the overall efficacy and clinical characteristics of successful macular hole closure with topical therapy, drops achieved an overall closure rate of 36.7%, with higher efficacy in smaller holes and those without VMT. Rates of MH narrowing and reduction in central foveal thickness acted as predictors of effectiveness of drop therapy.

Association of Metformin and Other Diabetes Medication Use and the Development of New-Onset Dry Age-Related Macular Degeneration: A Case-Control Study.

Purpose: To investigate if metformin use is associated with decreased odds of developing new non-neovascular ("dry") age-related macular degeneration (AMD). Methods: Case-control study examining 194,135 cases with diagnoses of new-onset AMD between 2008 and 2017 and 193,990 matched controls in the Merative MarketScan Research Databases. The diabetic subgroup included 49,988 cases and 49,460 controls. Multivariable conditional logistic regressions identified the risks of exposures on the development of dry AMD. Main outcome measures were odds ratios (ORs) of developing dry AMD with metformin use. Results: In multivariable conditional logistic regression, any metformin use was associated with decreased odds of developing dry AMD (OR = 0.97; 95% confidence interval [CI], 0.95-0.99). This protective effect was noted for cumulative 2-year doses of metformin of 1 to 270 g (OR = 0.93; 95% CI, 0.90-0.97) and 271 to 600 g (OR = 0.92; 95% CI, 0.89-0.96). In a diabetic subgroup, metformin use below 601 g per 2 years decreased the odds of developing dry AMD (1-270 g: OR = 0.95; 95% CI, 0.91-0.99; 271-600 g: OR = 0.92; 95% CI, 0.89-0.96). Unlike in diabetic patients with diabetic retinopathy, diabetic patients without diabetic retinopathy had decreased odds of developing dry AMD with any metformin use (OR = 0.97; 95% CI, 0.94-0.998) and cumulative two-year doses of 1 to 270 g (OR 0.96; 95% CI, 0.91-0.998) and 271 to 600 g (OR = 0.92; 95% CI, 0.88-0.96). Conclusions: Metformin use was associated with decreased odds of developing dry AMD. The protective effect was observed for cumulative 2-year doses below 601 g. In diabetics, this association persisted, specifically in those without diabetic retinopathy. Therefore, metformin may be a strategy to prevent development of dry AMD.

Single-piece femtosecond-assisted mushroom keratoplasty in children.

PURPOSE: To report outcomes of femtosecond-assisted single-piece mushroom keratoplasty for the treatment of full-thickness corneal disease in pediatric patients with healthy endothelium. METHODS: Femtosecond-assisted mushroom keratoplasty was performed in 8 eyes of 8 patients (age range, 8-17 years) with central full-thickness corneal opacity. The single-piece mushroom-shaped graft consisted of a large anterior portion (9 mm in diameter; 250 µm in thickness) and a small posterior portion (6-6.5 mm). Donor and recipient corneas were prepared using the WaveLight FS200 laser (Alcon Laboratories, Fort Worth, TX). The donor cornea was oversized by 0.2 mm. Outcome measures were best spectacle-corrected visual acuity, spectacle refraction, topographic astigmatism, endothelial cell density, graft rejection, and graft failure at 1, 3, 6, and 12 months. RESULTS: Mean best spectacle-corrected visual acuity at 1, 3, 6, and 12 months was 0.28, 0.16, 0.13, and 0.10 logMAR; all patients achieved logMAR of at least 0.4 at 1, 3, 6, and 12 months. The mean refractive cylinder was 2.6 D, and mean endothelial cell loss was 13.3% at 12 months postoperatively. Two eyes had immunologic rejection episodes that were reversed with topical steroids. All corneas remained clear at final follow-up. CONCLUSIONS: Femtosecond-assisted mushroom keratoplasty is a viable surgical option for eyes of older pediatric patients with full-thickness corneal stromal disease and healthy endothelium. Mushroom keratoplasty combines the refractive advantage of a large keratoplasty with the immunologic advantage of a small keratoplasty. Single-piece femtosecond-assisted mushroom keratoplasty may have a mechanical advantage over regular penetrating keratoplasty.

Decompression retinopathy after glaucoma surgery in children.

Of 170 children who underwent 248 glaucoma procedures at a single center between 2005 and 2012, 13 eyes of 12 children (5.24%) developed decompression retinopathy, which resolved spontaneously, leaving no visible structural damage to the fundus structures. The mean age of children with hemorrhages was 39.2 ± 63.5 months; of those without, 8.0 ± 9.7 months. The fundus hemorrhages were peripapillary, subfoveal, dot-and-blot, and diffuse. Combined angle and filtering surgery with antimetabolite was the most common procedure performed in all eyes. There were no statistically significant differences between eyes with and without hemorrhages with respect to demographics or preoperative and operative characteristics. No definite ocular risk factor was identified for the occurrence of decompression retinopathy.