Related Experiment Video
Updated: Jun 20, 2026
Full-Field Optical Coherence Microscopy for Histology-Like Analysis of Stromal Features in Corneal Grafts
Published on: October 21, 2022
Scheimpflug Tomographic Indices for Classifying Normal, Down Syndrome and Clinical Keratoconus in Pediatric Patients
Renato Souza Oliveira1,2,3, João Quadrado Gil2,4, Andreia Rosa2,4
1Instituto Brasileiro de Oftalmologia-IBOL, Rio de Janeiro 22250-145, Brazil.
Insights
Pentacam indices accurately diagnose keratoconus (KC) in pediatric patients with Down Syndrome (DS), but require specific cutoff values. Standard thresholds may lead to misdiagnosis in the DS population.
Area of Science:
- Ophthalmology
- Genetics
- Medical Imaging
Background:
- Down Syndrome (DS) patients exhibit corneal changes resembling keratoconus (KC).
- Accurate diagnosis of KC in pediatric patients with DS is challenging due to overlapping corneal features.
Purpose of the Study:
- Evaluate Pentacam indices for diagnosing KC in pediatric patients with and without DS.
- Determine specific cutoff values for Pentacam indices in pediatric DS patients.
Main Methods:
- Prospective, multicenter, cross-sectional study of 216 eyes from 131 pediatric patients (6-18 years).
- Categorization into KC, forme fruste keratoconus (FK), DS, and control groups.
- Analysis using Pentacam and receiver operating characteristic curves.
Main Results:
- Several Pentacam indices demonstrated high accuracy (AUC > 0.94) in distinguishing KC in DS patients.
- Indices like average pachymetric progression and anterior/posterior elevation were most effective.
- No indices showed good accuracy for distinguishing FK in DS patients.
- Thresholds for diagnosing KC in DS patients differed significantly from non-DS patients.
Conclusions:
- Pentacam indices are valuable for KC diagnosis in pediatric DS patients.
- DS-specific cutoff values are essential to prevent misdiagnosis.
- Further research is needed to establish reliable diagnostic criteria for FK in pediatric DS patients.
Abstract:
The study aimed to evaluate the precision of different Pentacam indices in diagnosing keratoconus (KC) in pediatric patients with and without Down Syndrome (DS) and determine suitable cutoff values. This prospective multicenter cross-sectional study evaluated 216 eyes of 131 patients aged 6-18 years (mean age 12.5 ± 3.2 years) using Pentacam. Patients were categorized into four groups: KC, forme fruste keratoconus (FK), DS, and control, excluding DS patients with topographic KC. Receiver operating characteristic curves were generated to determine the optimal cutoff points and compare the accuracy in identifying KC and FK in patients with and without DS. In DS patients, corneal morphology resembled KC features. The most effective indices for distinguishing KC in DS patients were the average pachymetric progression index (AUC = 0.961), higher-order aberration of the anterior cornea (AUC = 0.953), anterior elevation (AUC = 0.946), posterior elevation (AUC = 0.947), index of vertical asymmetry (AUC = 0.943), and Belin/Ambrosio enhanced ectasia total derivation value (AUC = 0.941). None of the indices showed good accuracy for distinguishing FK in DS patients. The thresholds of these indices differed significantly from non-DS patients. The results highlighted the need for DS-specific cutoff values to avoid false-positive or false-negative diagnoses in this population.
