Effect of Axial Length of the Globe on Retinal Nerve Fibre Thickness

Effect of Axial Length on Peripapillary Retinal Nerve Fibre Layer (RNFL) Using Optical Coherence Tomography (OCT)

the goal of this obsrevational study is to learn about retinal nerve fibres and if their numbers changed with axial length of the globe or not. the main question to answer is there is effect of long axial length on the thickness of the retinal nerve fibers participants will be asked to:

• measure the axial length with ultrasound
• measure the thickness of retinal nerve fibers with optical coherence tomography

Study Overview

• Status: Not yet recruiting
• Conditions: Myopia
• Intervention / Treatment: Diagnostic test: Optical coherence tomography (OCT)

Detailed Description

Aim of the work:

To investigate the effect of axial length on the peripapillary retinal nerve fiber layer.

Patients and methods Study design: Cross sectional comparative study. Location: Ophthalmology department, Sohag teaching hospital. Ethical approval: A written informed consent will be taken from all patients about the aim of the study, the nature of the planned investigation. An approval of the ethical committee of Sohag Faculty of Medicine will be fulfilled.

Methodology The study will include 80 patients healthy volunteers who underwent ophthalmologic examinations including retinal nerve fiber layer (RNFL) thickness analysis with optical coherence tomography (OCT), auto refraction, and axial length measurement.

Inclusion criteria:

Healthy volunteers attending the outpatient clinic for surface ocular diseases.

Exclusion criteria:

• Glaucoma patients.
• Media opacity (corneal, lens or vitreous opacity)
• Previous ocular surgery.
• Diabetic patients.
• Retinal diseases.

Method of the study:

1. Detailed ophthalmological and medical history.
2. Detailed slit lamp examination.
3. Visual acuity (VA) and best corrected visual acuity (BCVA) using Snellen chart and recorded in decimal notation.
4. Auto refraction using Topcon auto refractometer RM-800.
5. Optical coherence tomography (OCT) scan of retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness using Avanti scanner Optovue.
6. Axial length (AL) measured by E-Z scan 5500 sonomed A-scan ultrasound and biometry.

The patients will be divided into 3 groups:

Group 1 patients with axial length less than 21 mm. Group 2 patients with axial length 21-24 mm. Group 3 patients with axial length more than 24 mm.

• Study Type: Observational
• Enrollment (Anticipated): 80

Contacts and Locations

• Study Contact: Name: Asmaa I Mostafa; Phone Number: 01098794745; Email: asmaaelmalah8@gmail.com
• Study Contact Backup: Name: Engy Mo Mostafa, MD; Phone Number: 01005643587

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Outpatient ophthalmology clinic

Description

Inclusion Criteria:

• Healthy volunteers attending the outpatient clinic for surface ocular diseases.
• patients who are cooperative with optical coherence tomography (OCT) device.

Exclusion Criteria:

• Glaucoma patients.
• Media opacity (corneal, lens or vitreous opacity)
• Previous ocular surgery.
• Diabetic patients.
• Retinal diseases.

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Group 1 short axial length (AL); Axial length less than 21	Diagnostic test: Optical coherence tomography (OCT); Measurement of retinal nerve fibre layer (RNFL) thickness using optical coherence tomography
Group 2 average axial length (AL); Axial length 21-24	Diagnostic test: Optical coherence tomography (OCT); Measurement of retinal nerve fibre layer (RNFL) thickness using optical coherence tomography
Group 3 long axial length (AL); Axial length more than 24	Diagnostic test: Optical coherence tomography (OCT); Measurement of retinal nerve fibre layer (RNFL) thickness using optical coherence tomography

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Retinal nerve fibre layer (RNFL) thickness	Measuring Retinal nerve fibre layer (RNFL)thickness using OCT	average of one year

Collaborators and Investigators

• Sponsor: Sohag University
• Investigators: Study Director: Engy Mo Mostafa, MD, Sohag University

Study record dates

Study Major Dates

• Study Start (ANTICIPATED): February 1, 2023
• Primary Completion (ANTICIPATED): June 1, 2023
• Study Completion (ANTICIPATED): January 1, 2024

Study Registration Dates

• First Submitted: January 8, 2023
• First Submitted That Met QC Criteria: February 6, 2023
• First Posted (ACTUAL): February 8, 2023

Study Record Updates

• Last Update Posted (ACTUAL): February 8, 2023
• Last Update Submitted That Met QC Criteria: February 6, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: RNFL; Axial length
• Additional Relevant MeSH Terms: Eye Diseases; Refractive Errors; Myopia
• Other Study ID Numbers: Soh-Med-22-12-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No