Retinal nerve fiber thickness and MRI white matter abnormalities in healthy relatives of multiple sclerosis patients

Objectives: To compare retinal nerve fiber (RNFL) thickness and conventional and non-conventional MRI characteristics of healthy controls (HCs) from the general population (non-fHC) to healthy relatives of multiple sclerosis (MS) patients (fHC).

Methods: Sixty-eight (68) HCs underwent optical coherence tomography (OCT) and 3T MRI examination. Subjects were classified based on whether or not there was a family history of MS. The study enrolled 40 non-fHC who had no relatives with MS and 28 fHC with at least one relative affected with MS. The associations between OCT parameters and conventional and non-conventional MRI measures were investigated.

Results: There were no significant OCT or conventional and non-conventional MRI measureable differences between the non-fHC and fHC groups. Periventricular localization and total volume of white matter (WM) signal abnormalities (SA) were more common in the fHC group but the differences did not reach a level of significance. A significant association between decreased RNFL thickness with increased volume (p=0.001), number (p=0.003) and frequency of ≥ 9 T2 (p=0.003) WM SAs on MRI was found in the fHC group. No association between OCT and MRI parameters was detected in the non-fHC group.

Conclusion: There is an association between decreased RNFL thickness on OCT and increased WM injury in healthy relatives of MS patients. Further studies should explore the pathophysiology of these findings.