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Updated: Jun 12, 2026

Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla
08:51

Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla

Published on: February 19, 2021

A Pre-symptomatic phase of tumefactive multiple sclerosis mirrors radiologically isolated syndrome

Albert Aboseif1, Nur Neyal2, B Mark Keegan1

  • 1Division of Multiple Sclerosis and Autoimmune Neurology, Department of Neurology, Mayo Clinic, Rochester, MN, USA; Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, MN, USA.

Multiple Sclerosis and Related Disorders
|June 10, 2026
PubMed
Abstract

Insights

A pre-symptomatic phase of tumefactive multiple sclerosis (TMS) may be underrecognized. This study found similar frequencies and symptomatic evolution in pre-symptomatic TMS compared to non-tumefactive MS (nTMS).

Area of Science:

  • Neurology
  • Neuroimmunology
  • Radiology

Background:

  • Tumefactive multiple sclerosis (TMS) presents with large demyelinating lesions and severe attacks.
  • A pre-symptomatic phase, akin to radiologically isolated syndrome (RIS) in MS, is not well-defined for TMS.

Purpose of the Study:

  • To characterize the pre-symptomatic phase of TMS.
  • To compare the frequency and symptomatic evolution of pre-symptomatic TMS with a matched cohort of non-tumefactive MS (nTMS).

Main Methods:

  • Included adults (≥18 years) with tumefactive demyelinating lesions (TDL; ≥2 cm) meeting 2024 McDonald Criteria.
  • Defined pre-symptomatic TMS as incidental TDLs meeting pre-symptomatic MS criteria.
  • Compared pre-symptomatic disease frequency and symptomatic evolution to a matched nTMS cohort using Fisher's exact test and Kaplan-Meier analysis.

Main Results:

  • Seven of 202 TMS patients (4%) had pre-symptomatic disease (median age 51 years).
  • The frequency of pre-symptomatic disease was 3.1% in TMS versus 5.4% in nTMS (p=0.54) after matching.
  • Symptomatic evolution rates were similar between pre-symptomatic TMS (25%) and nTMS (14%) cohorts (p=1.0), though event numbers were limited.

Conclusions:

  • A pre-symptomatic phase of TMS, similar to RIS, may be underrecognized.
  • Incidental tumefactive brain lesions warrant evaluation for a potential pre-symptomatic phase.
  • Larger studies are needed to clarify differences in symptomatic evolution between pre-symptomatic TMS and nTMS.
Keywords:
AsymptomaticDemyelinationIncidentalMSPresymptomaticRISTumefactive

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