Which imaging modality is most sensitive for detecting vertebral osteomyelitis or epidural abscess?

• A. Ultrasound
• B. CT scan
• C. Plain X-ray
• D. MRI with contrast

Answer: (D)

MRI with gadolinium contrast is the most sensitive way to detect vertebral osteomyelitis and epidural abscess because it can visualize early bone marrow edema, disc involvement, and soft-tissue collections, all in one study. The contrast helps reveal abscesses, which often show rim enhancement, and diffusion sequences can further differentiate abscess from inflammatory edema. This makes MRI superior for identifying infection before there are obvious bony destructions or radiographic changes. If MRI isn’t possible, CT with contrast can show bone destruction and some epidural collections but misses early marrow edema and soft-tissue detail compared with MRI. Ultrasound isn’t suitable for spine infections, and plain X-ray changes appear late.