Fuchs Endothelial Corneal Dystrophy
Conditions
Keywords
Fuchs Endothelial Corneal Dystrophy, Cataract Surgery, endothelial keratoplasty, Diagnostic Accuracy, Prognostic Validation, Predictive Modeling
Brief summary
This prospective multicenter diagnostic study aims to externally validate and extend the SUCCESS Score for predicting the need for endothelial keratoplasty after cataract surgery in patients with Fuchs endothelial corneal dystrophy (FECD). The model's performance and clinical utility are assessed using discrimination, calibration, and reclassification metrics.
Detailed description
Fuchs endothelial corneal dystrophy (FECD) is a progressive corneal disorder characterized by endothelial cell loss, corneal edema, and visual impairment. In patients with FECD and cataract, an important clinical challenge is to predict whether cataract surgery alone will suffice or whether endothelial keratoplasty (EK) will be required postoperatively. Accurate preoperative risk stratification is essential for surgical planning and patient counseling. The SUCCESS Score, derived from Scheimpflug tomography, was proposed as an objective index to estimate the risk of postoperative corneal decompensation in FECD. However, its external multicenter validation and the potential contribution of corneal densitometry have not yet been fully established. This ongoing prospective, observational, multicenter study aims to externally validate and extend the SUCCESS Score for predicting the need for EK after cataract surgery in patients with FECD. The study is being conducted across five tertiary referral centers in Spain. Eligible participants are adults with FECD grade ≥2 on the modified Krachmer scale and a visually significant cataract requiring phacoemulsification. Patients with epithelial edema, prior ocular surgery, corneal infection, or trauma are excluded. Preoperative evaluation includes Scheimpflug tomography and corneal densitometry analysis. The primary outcome is the requirement for endothelial keratoplasty after cataract surgery, determined by postoperative visual function and corneal evaluation. Model performance will be assessed through discrimination (Harrell's C statistic), calibration, reclassification (IDI, NRI), and decision curve analysis to estimate clinical utility. The primary analysis is scheduled for completion in October 2024. Extended follow-up will continue until June 25, 2026, to assess long-term predictive performance and generalizability of the extended SUCCESS model. An interactive web-based calculator implementing both the original and extended SUCCESS models will be provided as a supplementary tool to facilitate clinical use and standardized patient counseling across participating centers.
Interventions
PROCEDUREPhacoemulsification Cataract Surgery
Standard phacoemulsification cataract surgery performed in patients with Fuchs endothelial corneal dystrophy (FECD). All procedures are carried out according to institutional protocols at participating tertiary centers. Preoperative Scheimpflug tomography and corneal densitometry measurements are collected to calculate the SUCCESS Score and evaluate the risk of postoperative endothelial decompensation. Postoperative outcomes are monitored to determine whether endothelial keratoplasty (EK) is required during follow-up.
Sponsors
Instituto Ramón y Cajal de Investigación Sanitaria
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
40 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adults aged ≥40 years. * Clinical diagnosis of Fuchs endothelial corneal dystrophy (FECD) grade ≥2 on the modified Krachmer scale. * Presence of visually significant cataract requiring phacoemulsification surgery. * Ability to provide informed consent and comply with study procedures. * Availability of preoperative Scheimpflug tomography and corneal densitometry measurements.
Exclusion criteria
* Epithelial or stromal edema precluding reliable corneal imaging. * Previous ocular surgery (including corneal or intraocular procedures). * Corneal trauma, infection, or inflammation affecting endothelial integrity. * Coexisting ocular pathologies that could confound postoperative assessment (e.g., advanced glaucoma, macular degeneration).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Need for endothelial keratoplasty (EK) after cataract surgery in patients with Fuchs endothelial corneal dystrophy | Up to 36 months after cataract surgery | The primary outcome is the need for endothelial keratoplasty (EK) following phacoemulsification cataract surgery in patients with Fuchs endothelial corneal dystrophy (FECD). The endpoint is determined based on postoperative best-corrected visual acuity, corneal clarity, and presence of clinical signs of corneal decompensation. Each eye is evaluated using standardized follow-up visits and imaging criteria across participating centers. The decision to perform EK is made according to established clinical indications by the attending ophthalmologist, ensuring consistency across study sites. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Model discrimination (Harrell's C statistic) of the SUCCESS Score | At primary analysis (October 2024) | Model discrimination will be assessed using Harrell's C statistic (concordance index) to quantify how accurately the SUCCESS Score predicts the need for endothelial keratoplasty after cataract surgery in patients with FECD. |
| Calibration and predictive accuracy of the SUCCESS Score | At primary analysis (June 2026) | Calibration plots and Brier score will be used to evaluate the agreement between predicted and observed probabilities of endothelial keratoplasty. Goodness-of-fit will be assessed across deciles of predicted risk. |
| Reclassification and clinical utility of the extended SUCCESS model | At primary analysis (June 2026) | The incremental value of adding corneal densitometry to the SUCCESS Score will be assessed using Integrated Discrimination Improvement (IDI), Net Reclassification Improvement (NRI), and Decision Curve Analysis (DCA) to determine potential clinical benefit. |
Countries
Spain
Contacts
Primary ContactFrancisco Arnalich-Montiel, PhD
Outcome results
None listed