Improved MRI quantification of spinal cord atrophy in multiple sclerosis

Area of Science:

• Neuroimaging
• Neurology
• Medical Imaging Analysis

Background:

• Multiple sclerosis (MS) is a demyelinating disease affecting the central nervous system.
• Accurate measurement of spinal cord cross-sectional area (CSA) is crucial for monitoring MS progression and treatment efficacy.
• Existing MRI-based methods for CSA measurement have limitations in reproducibility.

Purpose of the Study:

• To identify an improved and highly reproducible method for measuring cervical spinal cord CSA using magnetic resonance imaging (MRI) in multiple sclerosis (MS).
• To compare the reproducibility of different MRI sequences and analysis techniques for spinal cord CSA measurement.

Main Methods:

• 15 controls and 15 MS patients underwent cervical cord MRI, with repeat scans at 6 months for reproducibility assessment.
• Two MRI sequences (3D PSIR and 3D MPRAGE) were used.
• Spinal cord CSA at C2-C3 was measured using semiautomated edge detection and active surface model (ASM) methods.
• Reproducibility was evaluated using coefficient of variation (COV) and intraclass correlation coefficient.

Main Results:

• The 3D PSIR sequence combined with the ASM analysis method demonstrated the lowest COV values for intrarater, interrater, and scan-rescan reproducibility (0.002%, 0.03%, 0.1%).
• No significant changes in spinal cord CSA were observed in controls at 6-month follow-up.
• A trend towards significant CSA changes was noted in MS patients over the 6-month period.

Conclusions:

• The PSIR/ASM combination is a more reproducible method for spinal cord CSA measurement in MS compared to established techniques.
• This improved reproducibility allows for reduced sample sizes in clinical trials.
• The method facilitates more efficient and reliable monitoring of longitudinal cord atrophy in MS clinical trials.