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Comparative Assessment of Corneal Imaging Devices for Pediatric Patients: Evaluating Keratometric Measurements and
Renato Souza Oliveira1,2,3,4, João Quadrado Gil2,3,5, Maria João Quadrado2,3,5
1Instituto Brasileiro de Oftalmologia - IBOL, Rio de Janeiro, Brazil.
Purpose:
To evaluate the intrasession repeatability and agreement in keratometric and wavefront measurements among three different instruments (Pentacam HR, Nidek OPD-Scan III [OPD], and Zeiss i-Profiler [IPROF]) in a pediatric population with various clinical features.
Methods:
This cross-sectional study included 217 eyes from 114 patients aged 6 to 17 years with different clinical features. The patients were divided into five groups: one control group (C) and four other groups, each presenting with keratoconus (KC), ocular allergy (OA), high astigmatism, or Down syndrome (DS). Statistical analyses included the intraclass correlation coefficient (ICC) for repeatability and Bland-Altman plots for agreement.
Results:
The findings demonstrated excellent repeatability of keratometric parameters across all devices (e.g., K1 ICC: 99.53% for Pentacam, 98.10% for OPD, and 98.31% for IPROF). The Pentacam showed superior repeatability for aberrometry indices in the KC group, with ICC values exceeding 98% for high-order aberration root mean square (HOA RMS) and Zernike polynomials. However, in the DS group, repeatability was significantly reduced for certain parameters, such as the index of surface variance (ICC: 40.13%) and HOA RMS (ICC: 42.86%). Bland-Altman plots revealed variations among devices in asphericity, vertical coma, and HOA RMS, with the KC group exhibiting broader limits of agreement compared to the control group.
Conclusion:
All three instruments showed good repeatability, with the Pentacam demonstrating superior reliability across all parameters, including aberrometry. However, agreement between devices was poor for key indices in patients with KC and DS.

