Spinal cord and infratentorial lesions in radiologically isolated syndrome are associated with decreased retinal ganglion cell/inner plexiform layer thickness.

BACKGROUND

The role of retinal imaging with optical coherence tomography (OCT) in assessing individuals with radiologically isolated syndrome (RIS) remains largely unexplored.

OBJECTIVE

To assess retinal layer thicknesses in RIS and examine their associations with clinical features suggestive of increased risk for conversion to multiple sclerosis (MS).

METHODS

A total of 30 RIS subjects and 60 age- and sex-matched healthy controls (HC) underwent retinal imaging with spectral-domain OCT, followed by automated segmentation of retinal layers.

RESULTS

Overall, retinal layer thicknesses did not differ between RIS and HC. However, RIS subjects with spinal cord (SC) lesions had lower ganglion cell + inner plexiform layer (GCIP) thickness compared to HC (-4.41 μm; p = 0.007) and RIS without SC lesions (-3.53 μm; p = 0.041). Similarly, RIS subjects with infratentorial (IT) brain lesions had lower GCIP thickness compared to HC (-4.07 μm; p < 0.001) and RIS without IT lesions (-3.49 μm; p = 0.029). Multivariate analyses revealed that the presence of SC or IT lesions were independently associated with lower GCIP thickness in RIS (p = 0.04 and p = 0.03, respectively). Other patient characteristics, including sex, abnormal cerebrospinal fluid, and presence of gadolinium-enhancing or juxtacortical lesions, were not associated with retinal layer thicknesses.

CONCLUSION

The presence of SC or IT lesions in RIS may be associated with retinal neuro-axonal loss, supporting the presence of more disseminated disease.