Retinal inner nuclear layer volume reflects inflammatory disease activity in multiple sclerosis; a longitudinal OCT...

Area of Science:

• Ophthalmology
• Neuroscience
• Immunology

Background:

• Established association between retinal nerve fibre layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness with neurodegeneration in multiple sclerosis (MS).
• Limited understanding of the inner nuclear layer's (INL) relationship with inflammatory disease activity in MS.

Purpose of the Study:

• Investigate the relationship between inner nuclear layer (INL) volume changes and inflammatory disease activity in multiple sclerosis (MS).

Main Methods:

• Longitudinal, multi-centre study involving 785 MS patients and 92 healthy controls.
• Optical coherence tomography (OCT) and clinical data (disability, relapses, MS optic neuritis - MSON) collected between 2010-2017.
• Retrospective pooling of data on pRNFL, GCIPL, and INL from 11 MS centres.

Main Results:

• Significant increase in INL volume observed in eyes with new MSON (p < .001).
• Clinical relapses, excluding MSON, were significantly associated with increased INL volume (p = .025).
• INL volume changes were independent of overall disease progression (p = .474).

Conclusions:

• Increased INL volume is associated with MSON and clinical relapses in MS patients.
• INL volume changes show potential as an outcome marker for inflammatory activity in MS.
• This finding could be valuable for MS treatment trials and monitoring inflammatory disease activity.