Regional Analysis of Inner Retinal Layer Changes in Multiple Sclerosis with and without Optic Neuritis

Area of Science:

• Ophthalmology
• Neuroscience
• Immunology

Background:

• Multiple sclerosis (MS) is a chronic inflammatory disease affecting the central nervous system.
• Inner retinal layers, including the ganglion cell layer (GCL) and inner plexiform layer (IPL), are vulnerable to neurodegeneration in MS.
• Optic neuritis (ON) is a common initial symptom of MS, often leading to visual impairment.

Purpose of the Study:

• To investigate inner retinal changes in patients with relapsing-remitting multiple sclerosis (MS).
• To compare retinal layer thicknesses between MS patients and healthy controls.
• To assess regional differences in inner retinal layer involvement in eyes with and without a history of optic neuritis (ON).

Main Methods:

• Retrospective, cross-sectional study of 141 eyes from 74 MS patients and 80 eyes from 40 healthy controls.
• Comparison of peripapillary retinal nerve fiber layer (pRNFL), macular RNFL (mRNFL), GCL, IPL, and inner nuclear layer thicknesses.
• Subgroup analysis based on the presence or absence of a history of ON.

Main Results:

• Significantly thinner pRNFL, total macular, mRNFL, GCL, and IPL thicknesses were observed in MS patients compared to controls (p<0.001).
• Eyes with a history of ON exhibited significantly reduced thicknesses in these retinal layers compared to eyes without ON history (p<0.05).
• All inner 3-mm ring subfields of the GCL and IPL showed significant thinning in eyes with ON, with the inferior subfield demonstrating the most pronounced difference.

Conclusions:

• Ganglion cell layer (GCL) and inner plexiform layer (IPL) thinning are reliable biomarkers in all MS patients.
• The degree of GCL and IPL thinning is significantly greater in eyes with a history of ON.
• The inferior retinal region shows the most substantial GCL and IPL thinning following ON attacks in MS patients.