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Updated: Aug 5, 2026
12:22
Multimodal Volumetric Retinal Imaging by Oblique Scanning Laser Ophthalmoscopy (oSLO) and Optical Coherence Tomography (OCT)
Published on: August 4, 2018
Agreement between structural parameters provided by the swept-source OCT and Laguna ONhE
Gilvan Vilarinho da Silva Filho1, Gustavo Coelho Caiado1, Olívia Moura de Paula Ricardo2
1Glaucoma Service, Department of Ophthalmology and Visual Science, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
Arquivos Brasileiros De Oftalmologia
|July 29, 2026
Summary
The Laguna ONhE software underestimates optic nerve head disc area and cup-to-disc ratios compared to swept-source optical coherence tomography. Calibration improves agreement, making Laguna ONhE a potentially cost-effective glaucoma evaluation tool.
Area of Science:
- Ophthalmology
- Medical Imaging
- Glaucoma Research
Background:
- Accurate measurement of optic nerve head (ONH) structural parameters is crucial for glaucoma diagnosis and management.
- Swept-source optical coherence tomography (SS-OCT) provides high-resolution ONH imaging.
- The Laguna ONhE software offers automated ONH analysis.
Purpose of the Study:
- To assess the agreement between ONH parameters derived from SS-OCT and the Laguna ONhE software.
- To determine if calibration can improve the comparability of measurements.
Main Methods:
- Retrospective analysis of 353 eyes across various ocular health statuses.
- Measurement of ONH parameters (disc area, cup-to-disc ratios, rim volume) using SS-OCT and Laguna ONhE.
- Bland-Altman analysis for agreement assessment and development of a regression-based calibration model for disc area.
Main Results:
- Laguna ONhE showed systematic underestimation of disc area and cup-to-disc ratios (p < 0.001) and overestimation of rim volume (p=0.0002) compared to SS-OCT.
- Post-calibration, disc area measurements showed significantly improved agreement with no statistically significant bias (p=0.3).
Conclusions:
- The Laguna ONhE software provides structural estimates comparable to SS-OCT after applying a calibration equation for disc area.
- Calibrated Laguna ONhE may represent a practical and cost-effective alternative for glaucoma evaluation.
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