Prediction of Maximum Keratometry Progression With Stratified Progression Criteria in Keratoconus Patients Using Machine Learning

A Risk Prediction Model for Normal-Tension Glaucoma Progression Integrating Genetic Markers and Corneal Biomechanics.

A model integrating corneal biomechanical parameters, genetic risk scores, and tear molecular biomarkers was developed to predict the risk of NTG progression and demonstrated potential clinical utility.

Identification and risk-factor analysis for individuals at high risk for keratoconus via machine learning and logistic regression

ML models can distinguish high-risk KC groups based on clinical risk factors, facilitating risk stratification and early lifestyle interventions and confirmed by univariable logistic regression.

Influence of the Corneal Posterior-to-Anterior Radius Ratio on IOL Power Prediction Using Standard and Total Keratometry.

PURPOSE To compare the predictive accuracy of standard keratometry (K) and total keratometry (TK) for intraocular lens (IOL) power calculation across eyes stratified by the posterior-to-anterior corneal radius ratio (PAR). DESIGN Retrospective evaluation of IOL power calculation accuracy. METHODS A total of 1,314 eyes of 1,314 patients who underwent uneventful phacoemulsification with monofocal IOL implantation were enrolled. Preoperative biometry was performed with the IOLMaster 700 (Carl Zeiss Meditec). Eyes were divided into three subgroups according to the PAR: low (<25th percentile), moderate (25th-75th percentiles), and high (>75th percentile). Refractive prediction errors (PEs) were calculated with the Barrett Universal II (BUII) and Kane formulas, using both K and TK values. Main outcome measures were PE, median absolute error (MedAE), and the proportions of eyes within predefined absolute prediction error thresholds. RESULTS PAR was independently associated with the discrepancy between K- and TK-based prediction errors in both the BUII and Kane formulas (both P<0.001). Compared with conventional K, TK produced a consistent myopic shift in eyes with low PAR (-0.10 D for both formulas; both P<0.001) and a hyperopic shift in eyes with high PAR (+0.14 D for both formulas; both P<0.001), whereas only minimal changes were observed in eyes with moderate PAR. Despite these systematic directional shifts, MedAE remained comparable between K- and TK-based calculations across all PAR subgroups. In the high PAR subgroup, incorporation of TK significantly reduced the proportion of eyes within ±0.50 D of target refraction for the BUII formula (79.9% vs. 75.4%, P=0.041), whereas no significant difference was observed for the Kane formula. CONCLUSIONS PAR is an independent factor associated with the discrepancy between K- and TK-based refractive predictions. Rather than uniformly improving refractive accuracy, TK primarily induces systematic, PAR-dependent directional refractive shifts. These findings suggest that PAR may serve as a clinically useful biomarker for selecting between K- and TK-based calculations instead of supporting the routine use of TK in all eyes.

Prevalence of Abnormal Ectasia Screening Indices and the Predictive Value of Anterior Keratometry in Refractive Surgery Candidates.

Abnormal ectasia screening indices were common but predominantly borderline, and anterior keratometry alone could not reliably triage which corneas require tomographic examination, indicating that keratometry alone cannot replace it where it is not.

Validation and extension of the SUCCESS score for Fuchs dystrophy after cataract surgery

Accurate preoperative identification of patients with Fuchs endothelial corneal dystrophy (FECD) who are at risk of requiring endothelial keratoplasty (EK) after cataract surgery remains challenging. The SUbClinical Corneal Edema Scheimpflug Study (SUCCESS) score was previously developed to estimate this risk using Scheimpflug tomography. We aimed to prospectively and externally validate the SUCCESS score in an independent multicenter cohort and determine whether the incorporation of corneal densitometry improves predictive performance and clinical utility. In this prospective multicenter cohort study, 207 eyes from 177 patients with FECD grade ≥ 2 and visually significant cataract were enrolled across six tertiary hospitals in Spain (June 2020 to October 2024), with follow-up through May 2025. After predefined exclusions, 178 eyes (149 patients) were analyzed. The original SUCCESS score was used without recalibration. An extended model incorporated peak mean corneal densitometry within the central 3-mm zone. Time-to-event analyses were performed using Cox proportional hazards models. Discrimination, calibration, reclassification, and clinical utility were assessed using Harrell’s C-index, Brier score, net reclassification index (NRI), integrated discrimination improvement (IDI), and decision curve analysis. Over a median follow-up of 37.0 months (interquartile range [IQR], 10.1–45.9), 38 eyes (21%) met the criteria for EK, with 82% of events occurring within 6 months after phacoemulsification. The original SUCCESS score demonstrated good discrimination (C-index = 0.80; 95% confidence interval [CI], 0.73–0.86) with slight underestimation of absolute risk (predicted 16.4% vs. observed 21.6%). Incorporation of corneal densitometry improved discrimination (C-index = 0.85; 95% CI, 0.79–0.90; ΔC = + 0.05; P = 0.0047), reduced prediction error (ΔBrier = − 0.019; P < 0.001), and enhanced risk reclassification (NRI = 0.39; 95% CI, 0.14–0.64; P = 0.002), including correct upward reclassification of 26% of eyes requiring EK. The extended model provided greater net benefit at relevant decision thresholds (25%–50%). In this multicenter external validation study, the SUCCESS score demonstrated a robust performance in predicting postoperative EK in FECD. The addition of corneal densitometry provided incremental improvements in discrimination and clinically meaningful risk stratification, particularly in intermediate-risk cases. Standardized Scheimpflug-based risk assessment may support individualized surgical planning and referral decisions.

Pachymetric Thresholds for Keratoconus Progression Based on MS-39 Measurement Precision.