MRI Myelography is a non-invasive technique that uses heavily T2-weighted sequences to visualize the CSF spaces, spinal cord, and nerve roots without contrast injection. Unlike CT myelography, it avoids ionizing radiation and intrathecal puncture.
📌 Indications for MRI Myelography
1. Spinal Canal Pathologies
- Disc herniation → defines nerve root compression
- Spinal stenosis (central, lateral recess, foraminal)
- Ossified ligamentum flavum and hypertrophy
2. Nerve Root & CSF Space Evaluation
- Nerve root avulsion (e.g., brachial plexus injury, post-trauma)
- Perineural cysts (Tarlov cysts)
- Nerve sheath tumors (schwannoma, neurofibroma)
- CSF flow obstruction
3. Post-Operative Spine
- Differentiates recurrent disc herniation vs postoperative fibrosis
- Detects arachnoiditis and post-surgical adhesions
4. CSF Leak & Spontaneous Intracranial Hypotension
- Localizes CSF leak site (spinal dural tear, meningeal diverticula)
- Alternative to CT myelography when radiation is undesirable
5. Congenital & Developmental Abnormalities
- Spinal dysraphism (tethered cord, lipomeningocele)
- Syringomyelia and hydromyelia
- Chiari malformation (associated cord changes)
6. Tumor and Infection Evaluation
- Intramedullary & extramedullary tumors → delineates cord compression
- Epidural abscess / arachnoiditis → CSF space distortion
🧠 Teaching Points
- MRI myelography is non-invasive and best for soft tissue & CSF space pathology.
- CT myelography may still be preferred for bony detail and dynamic leak localization.
- In postoperative spine, MRI myelography provides critical differentiation of recurrent disease vs scar.
