Our aim is to investigate the relation between retinal structures measured by optical coherence tomography (OCT) and brain parameters detected by quantitative MRI (qMRI) and MR-spectroscopy (MRS) in multiple sclerosis (MS) and clinically isolated syndrome (CIS); and their dynamics over time.

Forty-four consecutive newly diagnosed patients with suspect MS (N=22) or CIS (N=22) were prospectively included. RNFL and GCIPL were examined by OCT at baseline, year 1 and 2. Conventional MRI, qMRI and MRS were applied at baseline and year 1.  Inflammatory metabolite myo-inositol (mins) was measured using MRS. Brain and myelin volumes (BPV and MYV) and fractions (BPF and MYF) were examined  using qMRI. T-tests and ANOVA were used to examine group differences.  Repeated measure ANOVA were used for longitudinal study. Linear regression was used to investigate relationship between OCT and MRI parameters.

Twenty-two patients were diagnosed with MS within 2 years and 22 remained as CIS. Neuroinflammation reflected by lesions on MRI and oligoclonal IgG bands (OB) in cerebrospinal fluid (CSF) was more prominent in MS compared to CIS. Decreased GCIPL thickness, BPV, MYV, BPF and MYF were seen in MS compared to CIS .  Inflammatory metabolite mins concentration was higher in MS than  CIS. Longitudinal study showed consistency of decreased GCIPL in MS compared to CIS (p<0.01). RNFL showed marginal changes over time in MS. GCIPL correlated positively with BPV and MYV (p<0.05), but negatively with mins (p<0.05).

GCIPL thinning is associated with neuroinflammation and brain atrophy, suggesting that GCIPL can be used as surrogate marker in monitoring MS course.