Ces radiol. 2025, 79(1):45-51 | DOI: 10.55095/CesRadiol2025/006

Radiologically isolated syndrome (new criteria) - shifting MS diagnosis to preclinical stageReview article

Manuela Vaněčková¹, Pavel Ryška², Eva Kubala Havrdová³

¹ Oddělení MR, Radiodiagnostická klinika 1. LF UK a VFN, Praha

² Radiologická klinika LF UK a FN, Hradec Králové

³ Neurologická klinika a Centrum klinických neurověd 1. LF UK a VFN, Praha

Radiologically isolated syndrome (RIS) is defined as an incidental finding on magnetic resonance imaging (MRI) that is typical of multiple sclerosis (MS) in a patient without clinical symptoms of the disease. This term, along with its definition criteria, was first introduced in 2009. The newly revised 2023 RIS criteria aim to provide a more accurate and faster diagnosis compared to the original 2009 criteria. These criteria require at least one T2-hyperintense lesion in one of the four typical locations for MS, along with two of the following three features: spinal cord lesions, oligoclonal bands confined to the cerebrospinal fluid (but absent in the serum), or a new T2-hyperintense lesion (or, after contrast administration, a prominent lesion visible on follow-up MRI scans). An MRI diagnosis of RIS establishes a risk factor for conversion to clinically definite MS and a more severe disease course. These risk factors include the patient's age, the location of the lesions (infratentorial and intramedullary), and the presence of oligoclonal bands in the cerebrospinal fluid. These factors are critical when considering therapeutic interventions. Recent clinical trials have demonstrated that oral disease-modifying therapies can delay or prevent the first clinical event in patients with RIS. This shift in diagnosis and treatment considerations to preclinical stages places enormous pressure on ensuring precise diagnosis and management. It is essential that such patients are referred to MS centers for further specialized investigations. The forthcoming Revised McDonald Criteria of 2024 will classify individuals with additional cerebrospinal fluid markers and advanced MRI biomarkers as having preclinical MS. This highlights the importance of precise diagnosis and the need for radiologists and neurologists to familiarize themselves with the appropriate steps to ensure patients are monitored at highly specialized MS care centers.

Keywords: radiology isolated syndrome, multiple sclerosis, magnetic resonance imaging, subclinical, prodromal, diagnostic protocol.

Accepted: January 31, 2025; Published: April 22, 2025  Show citation