VEP Abnormalities in Treatment-Naïve CIS/Early RRMS Without Prior Optic Neuritis: Clinical, Radiological, and CSF...

Area of Science:

• Neuroscience
• Ophthalmology
• Immunology

Background:

• Visual evoked potentials (VEPs) are noninvasive tools for detecting subclinical visual pathway issues in multiple sclerosis (MS).
• Early MS diagnosis, including clinically isolated syndrome (CIS) and early relapsing-remitting MS (RRMS), is crucial for management.
• Investigating VEPs in treatment-naïve patients without prior optic neuritis offers insights into early disease processes.

Purpose of the Study:

• To determine the frequency of VEP abnormalities in treatment-naïve CIS/early RRMS patients without a history of optic neuritis.
• To explore associations between VEP abnormalities and baseline clinical, radiological, and cerebrospinal fluid (CSF) features.
• To identify potential early indicators of disease progression and underlying pathology.

Main Methods:

• Retrospective review of 101 treatment-naïve CIS/early RRMS patients diagnosed between January 2022 and July 2024.
• Standardized pattern-reversal VEP recordings and CSF analysis.
• Statistical analysis including group comparisons and multivariable logistic regression to assess VEP abnormality associations.

Main Results:

• VEP abnormalities were frequent: 69% showed latency prolongation (42% any, 27% bilateral) and 33% amplitude reduction (22% any, 11% bilateral).
• Latency prolongation correlated with higher oligoclonal band (OCB) counts and IgG index in CSF, indicating intrathecal immune activation.
• Male sex and pyramidal/brainstem-onset presentation were independently associated with reduced VEP amplitude.

Conclusions:

• VEP abnormalities are common in early MS, even without optic neuritis history.
• Reduced VEP amplitude may indicate early tissue dysfunction linked to adverse clinical features.
• Prolonged VEP latency associated with intrathecal immune activation suggests subclinical demyelination related to inflammatory activity.