7 Tesla MRI in Multiple Sclerosis: Insights From Its Use in Clinical Routine

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Seven Tesla (7T) MRI offers superior spatial resolution and signal-to-noise ratio compared to lower field strengths.
• This advancement facilitates enhanced visualization of multiple sclerosis (MS) lesions, including cortical and deep gray matter lesions.
• 7T MRI improves the detection of specific MS biomarkers such as paramagnetic rim lesions (PRLs) and the central vein sign (CVS), though cost and clinical experience remain adoption barriers.

Purpose of the Study:

• To evaluate the real-world clinical utility of 7T MRI in diagnosing and managing patients with suspected central nervous system (CNS) inflammatory disorders.
• To assess the impact of 7T MRI on patient management and diagnostic certainty from a single-center perspective.

Main Methods:

• A retrospective analysis of 61 patients referred for 7T MRI between June 2020 and June 2024 at University Hospital Bern.
• Comparison of 7T MRI findings with clinical data and previous 3T MRI reports to assess diagnostic value.
• Statistical evaluation of sensitivity, specificity, Positive Predictive Value (PPV), and Negative Predictive Value (NPV) for MS diagnosis.

Main Results:

• 7T MRI enabled lesion reclassification and confirmed MS diagnosis in 19 out of 47 patients with previously indefinite diagnoses.
• In 14 MS patients, 7T MRI clarified diagnostic uncertainties, leading to one diagnosis revision and informing treatment decisions in four patients (including escalation or discontinuation).
• 7T MRI demonstrated 89.5% sensitivity and 78.6% specificity for MS, with a PPV of 73.9% and NPV of 91.7%. MS patients were significantly more likely to exhibit CVS and PRLs.

Conclusions:

• Routine clinical use of 7T MRI enhances diagnostic certainty in complex MS cases.
• The findings suggest that 7T MRI has the potential to significantly impact clinical practice by improving the accuracy and timeliness of MS diagnosis and management.