The presence of spinal cord (SC) or infratentorial (IT) lesions in radiologically isolated syndrome (RIS) may be associated with retinal neuro-axonal loss, supporting the presence of more disseminated disease. This according to a recent study that sought to assess retinal layer thicknesses in RIS and examine its association with clinical features suggestive of increased risk for conversion to multiple sclerosis (MS). A total of 30 RIS subjects and 60 age- and sex-matched healthy controls (HC) underwent retinal imaging with spectral-domain optical coherence tomography (OCT), followed by automated segmentation of retinal layers. Researchers found:

• Overall, retinal layer thicknesses did not differ between RIS and HC.
• However, RIS subjects with SC lesions had lower ganglion cell + inner plexiform layer (GCIP) thickness compared to HC (−4.41 μm) and RIS without SC lesions (–3.53 μm).
• Similarly, RIS subjects with IT brain lesions had lower GCIP thickness compared to HC (–4.07 μm) and RIS without IT lesions (–3.49 μm).
• Multivariate analyses revealed that the presence of SC or IT lesions were independently associated with lower GCIP thickness in RIS.