NCT07241806

Measurment of Optic Disc Parameters, RNFL Thickness and Ganglion Cell Complex in Myopic, Hypermetropic and Emmetropic Patients Using OCT and Axial Length Measurments

Correlation Between Axial Length and Degree of Refractive Error With Optic Disc Parameters , Ganglion Cell Complex and Peripapillary RNFL Thickness

• Status: Not Yet Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 266 (estimated)
• Sponsor: Assiut University · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

To evaluate the optic disc parameters, thickness of ganglion cell complex (GCC), and thickness of peripapillary retinal nerve fiber layer (RNFL) in myopic and hyperopic and emmetrop patients using optical coherence tomography (OCT), and to correlate these changes with axial length and degree of refractive error.

Detailed description

Refractive errors, particularly myopia and hyperopia, are among the most common ocular conditions globally, affecting both children and adults . Myopia is frequently associated with axial elongation, which may induce structural changes in the posterior segment of the eye such as thinning of the peripapillary retinal nerve fiber layer (RNFL) and alteration of optic disc parameters . Hyperopia, conversely, is linked to shorter axial lengths and has been shown to affect retinal and optic nerve anatomy in distinct ways . Optical coherence tomography (OCT), particularly spectral-domain OCT (SD-OCT), allows for high-resolution imaging of the RNFL and ganglion cell complex (GCC), which are crucial for visual processing. These layers are known to undergo subtle changes not only due to disease processes like glaucoma or optic neuropathies but also as a result of anatomical differences induced by refractive status . While many studies have independently evaluated RNFL or GCC in myopic and hyperopic patients, few have directly compared these two refractive states while correlating structural findings with axial length and refractive error magnitude . Including an emmetropic control group provides a normative benchmark, enhancing the clinical relevance of the findings . This study seeks to fill this gap by offering a comparative structural analysis using OCT, aiming to enhance diagnostic sensitivity and understanding of optic nerve and macular changes in various refractive profiles.

Conditions

• Refractive Errors

Interventions

Type	Name	Description
DEVICE	OCT	Axial length measurement (using A-scan) Spectral-domain OCT: All the patients will undergo OCT imaging using NIDEK RS-330 Retina scan duo 2 (SD-OCT)(CO-LTD made in Japan 2017) with scan speed 70.000 axial scans per second and wavelength of 880 nm for: Peripapillary RNFL thickness in all quadrants GCC thickness (average, superior, inferior,nasal,temporal) Optic disc parameters (disc area, cup/disc ratio, rim area)

Timeline

• Start date: 2026-01-01
• Primary completion: 2027-11-01
• Completion: 2027-12-01
• First posted: 2025-11-21
• Last updated: 2025-11-21