Classification of intervertebral disk degeneration with axial T2 mapping

Area of Science:

• Radiology
• Biomedical Imaging
• Spine Imaging

Background:

• Intervertebral disk degeneration is a significant cause of back pain.
• Current MRI classification systems for disk degeneration have limitations in detecting early changes.
• T2 values in intervertebral disks correlate with compositional changes.

Purpose of the Study:

• To develop and evaluate an MRI classification system for intervertebral disks using axial T2 mapping.
• To specifically assess the system's ability to identify early degenerative changes.
• To compare the new T2 mapping classification with conventional grading systems.

Main Methods:

• Twenty-nine healthy volunteers underwent axial T2 mapping of lumbar intervertebral disks (L3-L4, L4-L5, L5-S1).
• Disk degeneration was graded using the novel axial T2 mapping system and two conventional MRI classification systems (nucleus pulposus signal intensity and sagittal morphology).
• The correlation between T2 values and degenerative grade was analyzed.

Main Results:

• Axial T2 mapping demonstrated larger T2 differences between higher degeneration grades (II-III, III-IV) compared to conventional methods.
• The novel system classified a higher proportion of disks into grades II and III, suggesting increased sensitivity to early degeneration.
• Conventional systems classified a higher ratio of disks as grade I (normal).

Conclusions:

• Axial T2 mapping provides a more objective, T2-based classification of intervertebral disks.
• This new MRI classification system shows potential for detecting early degenerative disk disease before it is apparent with conventional methods.