Kamran M. Riaz

Background/Objectives: Intraocular lens (IOL) constants are conventionally optimized globally across an entire calibration dataset, assuming that systematic prediction error is independent of axial length (AL). This assumption is known to fail in short and long eyes. We evaluated whether AL-segmented constant optimization reduces refractive prediction error, whether the benefit depends on formula family, and whether changepoints discovered in one population transfer to a disjoint one. Methods: In a pooled 6451-eye training dataset (6 IOL models), the corrected Akaike Information Criterion selected the optimal number (0–4) and positions of AL changepoints for six formulas (classic three-constant Haigis, new-Haigis H1/H2, SRK/T, Hoffer Q, Holladay 1), enforcing ≥40 eyes and ≥2.0 mm per segment. Locked changepoints were applied to two disjoint single-lens test subgroups (Vivinex, n = 887; SA60AT, n = 821; three-center retrospective cohort) and independently re-discovered within each. Root-mean-square prediction error (RMSE) reduction was assessed by bootstrap confidence interval, Diebold–Mariano test, and Wilcoxon signed-rank test. Results: Segmentation reduced training RMSE for all six formulas, particularly for Hoffer Q (−3.9%) and Holladay 1 (−2.8%; confidence intervals excluding zero, Diebold–Mariano p < 0.0001). With locked changepoints, both formulas again showed the largest test-dataset improvements (3.0–6.3%; confidence intervals excluding zero in all four lens–workflow combinations), followed by SRK/T (0.9–1.3%, up to 2.5% with independently discovered changepoints). Haigis-family formulas showed smaller reductions (0.2–1.6%) with confidence intervals including zero in several combinations. Conclusions: AL-segmented optimization benefits Hoffer Q and Holladay 1 most robustly—formulas lacking a direct anterior chamber depth predictor—with a smaller benefit for SRK/T and an inconsistent benefit for Haigis-family formulas. Changepoints from a pooled training population transfer usefully, though not optimally, to individual lens models.

Background To evaluate the effectiveness of same-day repeated scans using a swept-source optical coherence tomography (SS-OCT) biometer (IOLMaster 700) when the initial scan resulted in a “warning” and/or “failed” variable. Methods This is a retrospective observational cohort study at a tertiary care academic referral center. Among 5619 SS-OCT biometer scans reviewed between 2017 and 2021, 2293 met the inclusion criteria with 1167 same-day rescans. Each scan’s variables received a “successful,” “warning,” or “failed” result across nine biometric parameters: axial length, anterior chamber depth, central corneal thickness, keratometry, lens thickness, posterior keratometry, total keratometry, white-to-white distance, and aqueous depth. Scans achieving “successful” results for all nine variables were deemed “perfect scans.” Warning and failed results were analyzed separately for per-parameter analyses given their differing clinical implications for IOL power calculation. Results After excluding perfect initial scans, among 909 suspect sessions, only 361 (38.1%) rescans yielded better results, while 587 (61.9%) demonstrated an identical or worse outcome (95% CI: 59–65%, p < 0.001). When analyzing all nine variables across all rescans, the subsequent scan showed an identical or worse outcome in 804 (68.9%) cases (95% CI: 66–72%, p < 0.001). In rescans where the initial scan received a “warning” or “failed” result for any individual variable, 35.8–56.0% improved depending on the parameter. Among improved scans, mean absolute differences were minimal, suggesting limited clinical significance. Conclusions Repeat scans improve the quality of biometric measurements in eyes showing warning or failed results from the studied SS-OCT biometer in fewer than half of cases for most parameters.

Keratoconus (KC) is a degenerative corneal disease, characterized by stromal thinning and abnormal ECM remodeling, leading to fibrosis. Corneal fibrosis is a leading cause of visual impairment. Corneal stromal keratocytes differentiate into myofibroblasts, which alters extracellular matrix (ECM) protein deposition. Nintedanib (NIN) is an antifibrotic FDA-approved tyrosine kinase inhibitor, but its function in the cornea is largely unknown. This study examined the impact of NIN within the human corneal stromal microenvironment. Healthy corneal stromal fibroblasts (HCFs) and KC fibroblasts (HKCs) in 2D and 3D in vitro cultures were treated with 1 μM or 2.5 μM NIN. Cell types were evaluated in 2D cultures for metabolic activity, viability, and migration. Protein expression of alpha-smooth muscle actin (α-SMA), collagens (COLs) 1, 3, and 5, cellular fibronectin containing extra domain A (EDA-FN), and thrombospondin-1 (TSP-1) were evaluated in 3D cultures. NIN reduced metabolic activity in HKCs without affecting cell viability. NIN reduced cell migration, downregulated COL3, COL5, EDA-FN, and TSP-1 expression in HCFs and HKCs. COL1 was upregulated in HCFs, whereas α-SMA was upregulated in HKCs. Overall, these findings demonstrate that NIN modulates corneal stromal cell migration and fibrotic marker expression, highlighting its potential as a therapeutic strategy for reducing corneal fibrosis associated with keratoconus.

While many functional declines associated with aging are not reversible, vision loss due to cataracts and/or astigmatism are common and recoverable impairments. A cataract is defined by the opacifi...

Purpose: To evaluate the severity of keratoconus (KCN) at presentation in self-identified minority patients, identify risk factors for progression and surgery, and assess loss to follow-up. Material and Methods: Pentacam tomography records (2014– 2021) from a single academic center were screened for KCN using BAD-D ≥ 1.6 and Kmax ≥ 47D. Manual chart review confirmed diagnosis, determined severity, and assessed progression and surgical intervention within two years. Demographic, socioeconomic, and clinical parameters were recorded. Logistic regression and generalized linear mixed models were used to evaluate associations, with covariates selected from univariate analysis; final models were determined by backward elimination. The primary outcome was KCN severity at presentation; secondary outcomes were progression, surgery within two years, and loss to follow-up. Results: Of 21,157 charts reviewed, 797 patients had KCN; 479 were male (60.1%) and 458 (57.5%) identified as racial/ethnic minorities. Mean age at presentation was 41.7 ± 16.5 years. Severe disease was present in 635 (81.8%) patients. Patients with connective tissue disease were less likely to present with severe KCN (p = 0.0015). Younger age predicted surgical recommendation within two years (p = 0.008). Patients recommended for surgery were more likely to be younger (p = 0.008) and to speak a primary language other than English (p = 0.006). Two-year loss to follow-up (LTFU) was high (65.1%). Smokers were associated with a greater LTFU (p = 0.0475). However, patients with eczema (p = 0.0388) or those with other ocular diseases (p = 0.0058) were less likely to be LTFU. Conclusion: Markers of socioeconomic disadvantage cluster with worsened disease burden but only select factors remained independently associated after adjustment.

PURPOSE: To evaluate demographics, risk factors, clinical characteristics, and visual outcomes of fungal keratitis (FK) in Oklahoma over 5 years and identify factors linked to poor outcomes. METHODS: A retrospective chart review was conducted at the Dean McGee Eye Institute (University of Oklahoma) from January 2019 to February 2024, identifying 103 cases of FK among 1213 corneal ulcer patients. Poor outcomes were defined as final best corrected visual acuity (BCVA) ≤20/70 or need for surgery. Statistical comparisons were performed using the Chi-square test, Wilcoxon rank-sum test, and multivariate logistic and linear regression analyses. RESULTS: Overall, 42/103 (40.8%) of patients had poor outcomes. Mold was the most common etiology (74.8%). Topical steroid use (odds ratio 3.57, P = 0.0025) and poor contact lens (CL) hygiene ( P = 0.027) were both independently associated with worse outcomes. However, CL users had a better final BCVA than non-users ( P = 0.0138), possibly due to earlier presentation or less severe disease. Intrastromal antifungal injections and scleral lenses resulted in clinically significant mean VA improvements of 7.4 and 4 lines (logMAR-converted), respectively. CONCLUSION: The epidemiologic patterns observed in this geographic region of the United States, a mold-predominant environment with frequent steroid misuse and CL–associated disease, highlight the importance of early diagnosis, risk-factor modification, and ready access to adjunctive therapies. As FK incidence continues to rise in similar climates, these lessons from our regional cohort may help refine triage pathways and inform treatment approaches to reduce preventable vision loss.

To compare the performance of the Zeiss AI IOL Calculator (ZAIC) to that of Barrett Universal II (BUII) and Kane, using standard (K) and total keratometry (TK) as inputs. This was a multicenter retrospective case series which included surgery-naïve eyes undergoing cataract surgery with preoperative optical biometry on the IOLMaster 700, monofocal IOL (Bausch & Lomb enVista MX60E) implantation, and 20/40 acuity or better measured at least 3 weeks postoperatively. After taking the difference between actual and predicted postoperative spherical equivalent (SE) for each eye, optimized outcome measures included the mean absolute error (MAE), standard deviation (SD) of the mean prediction error, root mean squared absolute error (RMSAE), median prediction error (MedAE), and proportion of eyes within 0.5 D of predicted. Statistical differences were identified using Wilcox-Holladay-Wang-Koch tests with Holm correction. A total of 246 eyes of 246 patients were analyzed. The MAE of ZAIC was significantly lower than that of BU2 TK [0.30 vs 0.32 D (p = 0.04)]. ZAIC had a lower SD and RMSAE than that of BU2 K and BU2 TK [0.38 vs 0.41 (p = 0.001) and 0.42 D (p = 0.002); 0.38 vs 0.41 (p = 0.008) and 0.42 (p = 0.008)]. ZAIC also had a larger proportion of eyes within 0.5 D of predicted compared to BU2 K [82% vs 76% (p = 0.02)], as well as a larger proportion of eyes within 0.75 D of predicted compared to BU2 TK [95% vs 91% (p = 0.02)]. There were no significant differences in MedAE or the proportion of eyes within 0.25 or 1 D of predicted. Compared to BU2, ZAIC produces a lower MAE, SD, and RMSAE, and a higher proportion of eyes within 0.5 and 0.75 D of predicted but performs similarly to Kane across all outcome measures. This remains true regardless of whether K or TK is used as an input. This study is limited by its retrospective design and use of a single MX60E IOL model.

Purpose: To evaluate whether primary graft failure (PGF) rates and endothelial cell loss (ECL) differ between surgeon-trephined/loaded and eye bank-preloaded Descemet-stripping automated endothelial keratoplasty (DSAEK) grafts. Setting: Tertiary care academic center. Design: Retrospective case series and ex vivo laboratory study. Methods: Single-center review of 69 eyes undergoing DSAEK (2020-2023) divided into 3 groups based on graft preparation and eye bank source: (1) eye bank-preloaded in EndoSerter (PL-ES), (2) eye bank-preloaded in glass tube (PL-GT), and (3) surgeon-trephined/loaded in EndoSerter (SL-ES). The primary clinical outcome was PGF (persistent corneal edema >3 months despite medical therapy). Secondary outcomes included visual outcomes and clinical complications (cystoid macular edema [CME] and rebubbling rate [RR]). The primary outcome of the laboratory study was percentage ECL (%ECL). Results: All lenticules were ≤80 μm. PGF was significantly higher in the PL-ES group (8/20; 40%) and the PL-GT group (4/7; 57%) compared with the SL-ES group (1/42; 2%) ( P < .0001). Grafts requiring rebubbling were more likely to experience PGF ( P = .0176). PGF eyes were regrafted with SL-ES DSAEK; none experienced subsequent PGF. There were no significant differences in CME, RR, corrected distance visual acuity, and spherical equivalent. The ex vivo study included 9 PL-ES, 6 PL-GT, and 6 SL-ES grafts. %ECL was higher in both preloaded groups than SL-ES ( P = .0354), although significance was not demonstrated on post hoc analysis. Fluorescent imaging revealed more cell loss in preloaded grafts. Conclusions: Preloading and storage of DSAEK grafts may affect PGF rates clinically and ECL ex vivo.