SUCCESS Score Validation in Fuchs Dystrophy
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Phacoemulsification Cataract Surgery.
- Who it may be relevant to
- Registry conditions: Fuchs Endothelial Corneal Dystrophy. Basic parameters: from 40 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Spain
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Validation and Extension of the SUCCESS Score for Fuchs Dystrophy After Cataract Surgery
Overview
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
- Procedure Phacoemulsification 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 req
Primary outcome measures
- Need for endothelial keratoplasty (EK) after cataract surgery in patients with Fuchs endothelial corneal dystrophy [Time frame: Up to 36 months after cataract surgery]
Secondary outcome measures (3)
- Model discrimination (Harrell's C statistic) of the SUCCESS Score [Time frame: At primary analysis (October 2024)]
- Calibration and predictive accuracy of the SUCCESS Score [Time frame: At primary analysis (June 2026)]
- Reclassification and clinical utility of the extended SUCCESS model [Time frame: At primary analysis (June 2026)]
Eligibility criteria
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).
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Cohort
Study locations
Spain · 1 center
- Hospital Universitario Ramón y Cajal, Universidad de Alcalá, Instituto Ramón y Cajal de In — Madrid
Publications
- Arnalich-Montiel F, de-Arriba-Palomero P, Muriel A, Mingo-Botin D. A Risk Prediction Model for Endothelial Keratoplasty After Uncomplicated Cataract Surgery in Fuchs Endothelial Corneal Dystrophy. Am J Ophthalmol. 2021 Nov;231:70-78. doi: 10.1016/j.ajo.2021.04.016. Epub 2021 May 2. PMID 33951443
Identifiers
NCT: NCT07265388 · SUCCESS-FUCHS · PI22/01252