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

NCT ID: NCT07241806

Last Updated: 2025-11-21

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Total Enrollment: 266 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2026-01-31
• Study Completion Date: 2027-12-31

Brief 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

Study Design

• Observational Model Type: OTHER
• Study Time Perspective: CROSS_SECTIONAL

Interventions

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)

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Adults age starting from 18 years old Diagnosed with myopia (≤ -0.50 D) or hyperopia (≥ +0.50 D) Clear ocular media for high-quality OCT imaging No prior ocular surgeries Willing to provide informed consent IOP below 21

Exclusion Criteria

• Presence of glaucoma or optic nerve pathologies Retinal diseases or degenerative changes Systemic diseases affecting the eye (e.g., diabetes, hypertension) History of trauma or intraocular surgery High astigmatism (> ±2.00 D) Poor OCT image quality

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Assiut University

OTHER

Sponsor Role: lead

Responsible Party

Mariam Smeh Roshdy

doctor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Central Contacts

Mariam Sameh Roshdy

Role: CONTACT

romaa.sameh83@gmail.com

+201143288540

References

Holden BA, Fricke TR, Wilson DA, Jong M, Naidoo KS, Sankaridurg P, Wong TY, Naduvilath TJ, Resnikoff S. Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050. Ophthalmology. 2016 May;123(5):1036-42. doi: 10.1016/j.ophtha.2016.01.006. Epub 2016 Feb 11.

Reference Type: RESULT

PMID: 26875007 (View on PubMed)

Chen Y, Li X, Wang J, et al. Recent large-sample findings reinforcing the relationship between myopia (axial elongation) and reduced RNFL thickness, with discussion of magnification correction. Sci Rep. 2024;14(1):12567.

Reference Type: RESULT

Wu Z, Huang J, Wang Y, et al. Retinal structural changes associated with high refractive errors: A comparative OCT analysis. Eye (Lond). 2024;38(1):112-120.

Reference Type: RESULT

Hougaard JL, Wang M, Fjeldstad JS. Quantitative OCT findings in high myopia and hyperopia. Acta Ophthalmol. 2023;101(4):e315-e322.

Reference Type: RESULT

Liu S, Chen J, Xu Y, Li Y, Zhang X. Effects of refractive error on GCC and RNFL thickness: a meta-analysis. Eye Vis (Lond). 2023;10(1):14

Reference Type: RESULT

Wang D, Zhang Y, Chen H, Li L, Zhou Y. Evaluation of RNFL thickness in hyperopic eyes: a comparative OCT-based study. Int J Ophthalmol. 2022;15(4):599-605.

Reference Type: RESULT

. Leung CK, Yu M, Weinreb RN, Mak HK, Lai G, Ye C, et al. Impact of axial length on optic disc and retinal nerve fiber layer measurements. Invest Ophthalmol Vis Sci. 2011;52(1):291-9.

Reference Type: RESULT

. Kim M, Choi EH, Lee HS, Park SW, Kim JH, Yu YS. Peripapillary and macular retinal thickness in high myopia measured with OCT. BMC Ophthalmol. 2020;20(1):285.

Reference Type: RESULT

Related Links

https://pubmed.ncbi.nlm.nih.gov/26875007/

Related Info

Other Identifiers

OCT in refractive error

Identifier Type: -

Identifier Source: org_study_id