MRI Lumbar Spine — degenerative
From at least the T12/L1 level, including the conus medullaris, to the S1/S2 level, with axial sections through the lower lumbar discs at minimum.
Typical, not policy
Timings, volumes and delays here are representative values drawn from published guidance. Scanner generation, injector, cardiac output and local preference all move them. Confirm against your department's own protocol before you rely on a number.
When to use it
- Radicular leg pain persisting beyond a conservative-management period, where surgery or injection is being considered.
- Neurogenic claudication with suspected canal stenosis.
- Back pain with red flags where a structural cause must be excluded.
- Progressive motor deficit in a nerve root distribution.
- Pre-operative planning and level confirmation before decompression or fusion.
Technique
- Sagittal T1 and sagittal T2 through the lumbar spine, plus axial T2 through the lower lumbar levels; axial T1 is added in some protocols for foraminal fat.
- A sagittal fluid-sensitive fat-suppressed sequence is commonly included to detect marrow oedema, fracture and infection that T1/T2 alone can under-call.
- Coverage must include the conus: a conus lesion presenting as back pain is the classic miss.
- Angling axial stacks to the disc space improves foraminal assessment; contiguous non-angled stacks are an accepted alternative and centres differ.
Where it goes wrong
- Coverage starting below the conus, so an intramedullary or conus lesion is never in the field of view.
- Adding gadolinium to a straightforward degenerative study, which contributes nothing.
- Axial coverage limited to L4/5 and L5/S1 in a patient whose symptoms localise higher.
- Motion in a patient in severe pain producing an uninterpretable axial series — analgesia is a technical measure here.
- Imaging supine when the symptoms are postural; a supine study can understate dynamic stenosis, and this is a known limitation rather than a fixable one on a standard scanner.
Clinical questions that reach this study
Contrast
None
- Degenerative lumbar imaging needs no contrast. Contrast belongs to the post-operative, infective and neoplastic questions only.
Acquisition
- Breathing
- Free breathing.
- Preparation
- Suspected cauda equina syndrome is an emergency pathway with its own timing expectations, not a routine lumbar request. Say whether the patient has had previous lumbar surgery and at which level — it changes whether contrast is worth adding. Patients with severe pain may need analgesia before scanning to complete the axial series.
Safety checks this protocol carries
Derived from the contrast agent and phases above, not authored here — which is why they cannot drift apart from what the protocol actually does.
- MR safety screening for implants and foreign bodies· radiographer at scan