Conversion from radiologically isolated syndrome to multiple sclerosis

Area of Science:

• Neurology
• Radiology
• Clinical Research

Background:

• Radiologically isolated syndrome (RIS) is a condition with MRI findings suggestive of demyelination but no clinical symptoms.
• Estimating the conversion rate of RIS to definite multiple sclerosis (MS) is crucial for patient management.
• This study provides the first estimate of RIS to MS conversion in Iran.

Purpose of the Study:

• To estimate the conversion rate from radiologically isolated syndrome (RIS) to definite multiple sclerosis (MS).
• To identify potential predictors of conversion in a cohort of Iranian patients.

Main Methods:

• A single-center prospective study followed 25 subjects with RIS (aged 22-45) for a mean of 17.4 months.
• Definite MS diagnosis was based on the revised McDonald's criteria (2010).
• Initial brain MRI characteristics, including contrast-enhancing lesions, were analyzed.

Main Results:

• Six out of 25 (24%) RIS patients converted to definite MS.
• The conversion rate was 1.5 per 100 person-months (95% CI 0.54, 3.17).
• Contrast-enhancing lesions on initial MRI showed a marginal association with MS development (HR 1.83, P=0.060).

Conclusions:

• The conversion rate from RIS to definite MS in this Iranian cohort is high.
• Intensive follow-up and early intervention strategies are recommended for high-risk individuals.
• A larger study is needed to further elucidate the risk factors and conversion rates.