Comparison of individuals with radiologically isolated syndrome, early multiple sclerosis patients, and healthy controls using a digital neurological examination.

BACKGROUND

The revised McDonald criteria shifted toward the recognition of the radiologically isolated syndrome (RIS) as the first phase of the multiple sclerosis (MS) spectrum.

OBJECTIVES

To characterize differences between RIS individuals, early MS patients, and healthy controls (HCs) using a high-precision clinical assessment tool based on digital technology.

METHODS

We performed a multicentric, cross-sectional study involving RIS, early MS patients, and HC. Subjects were assessed using Neuraccure, an iPad application capable of detecting subtle abnormalities in four neurological functions: hand coordination, low-contrast vision, reaction time, and eye movements.

RESULTS

In total, 565 individuals were included (MS: 255, RIS: 146, HC: 164). HC performed better than RIS and MS across all digital measures (p < 0.0001 to 0.03). There was no statistical difference between RIS and MS patients, except for the coordination test, which was slightly worse in MS patients (p = 0.03). The receiver operating characteristic (ROC) analysis indicated that the presence of at least two impaired functions could detect RIS and MS from HC with 83.2% sensitivity and 84.3% specificity. A higher number of impaired functions were associated with lower brain magnetic resonance imaging (MRI) volumes.

CONCLUSION

High-precision neurological evaluation can distinguish HC from RIS and MS at an individual scale with a good performance.