Multifocal electroretinogram in non-pathological myopic subjects: correlation with optical coherence tomography

Area of Science:

• Ophthalmology
• Retinal Physiology
• Myopia Research

Background:

• Myopia is a prevalent refractive error with potential retinal complications.
• Assessing retinal function in non-pathological myopia is crucial for early detection of changes.
• Multifocal electroretinography (mfERG) and optical coherence tomography (OCT) are key tools for evaluating retinal function and structure.

Purpose of the Study:

• To investigate retinal function changes in non-pathological myopia using mfERG.
• To correlate mfERG findings with central macular thickness (CST) measured by OCT.
• To understand the relationship between the degree of myopia and retinal functional parameters.

Main Methods:

• 113 subjects (18-35 years) were categorized into emmetropia, low/medium, high, and super-high myopia groups based on spherical equivalent and axial length.
• mfERG recorded P1 amplitude density, P1 amplitude, and P1 implicit time across five retinal rings.
• Central subfield macular thickness (CST) was measured using Cirrus HD-OCT.

Main Results:

• P1 amplitude density and P1 amplitude decreased with increasing eccentricity in all groups.
• P1 implicit time progressively increased with higher levels of myopia across all retinal rings.
• Central macular thickness (CST) increased significantly with myopia severity (P<0.001).
• A negative correlation was found between CST and P1 amplitude/density, and a positive correlation with P1 implicit time.

Conclusions:

• Increasing myopia is associated with reduced retinal function, evidenced by diminished mfERG P1 amplitude density and amplitude.
• Thicker central macula in myopic eyes correlates with altered retinal function, suggesting potential visual cell dysfunction.
• Further research is needed to elucidate the exact mechanisms underlying these functional changes in myopia.