Should a lumbar spine CT be performed with or without intravenous contrast?

Lumbar Spine CT: Without Contrast is Preferred

For lumbar spine CT imaging, perform the study WITHOUT intravenous contrast in the vast majority of clinical scenarios, as IV contrast provides no diagnostic advantage for evaluating osseous structures, fractures, alignment, spinal stenosis, or neural foramina. 1, 2

Primary Recommendation

• CT lumbar spine without IV contrast is the standard protocol because it provides detailed analysis of fractures extending to the posterior column, evaluates pedicle integrity and posterior cortex, and accurately assesses spinal stenosis and neural foramina 1, 2

• CT with IV contrast alone does NOT provide additional information compared to non-contrast CT for evaluation of spinal fractures, alignment, or degenerative changes 1

• CT without and with IV contrast is not typically performed as there is no diagnostic advantage to performing both protocols together 1, 2

When CT Without Contrast Excels

• Preoperative planning: Delineates osseous margins and aids in trajectory planning for hardware fixation 1

• Fracture evaluation: Provides detailed analysis of vertebral body fractures, particularly posterior column involvement 1

• Spinal stenosis assessment: CT is equal to MRI for predicting significant spinal stenosis and excluding cauda equina impingement 1, 2

• Hardware evaluation: Assesses integrity of fusion, hardware position, and spinal alignment in post-surgical patients 2

• Facet joint evaluation: Accurately depicts facet arthropathy and osseous degenerative changes 3, 4

The Only Exception: Suspected Infection

• CT with IV contrast may be considered ONLY when evaluating for epidural abscess in patients with suspected spinal infection, though MRI with and without contrast remains vastly superior 2, 5

• Even in infection scenarios, non-contrast CT poorly depicts intradural and spinal cord pathologies and should not be the primary modality 2

Critical Limitations of CT (With or Without Contrast)

• Cannot adequately evaluate disc herniations, nerve root compression, or soft tissue pathology - MRI is superior for these indications 1, 6

• Poor visualization of marrow abnormalities, infection, and intradural pathologies regardless of contrast administration 2

• Cannot distinguish postoperative scar from recurrent disc herniation - this requires MRI with contrast 1

Alternative When CT is Inadequate

• CT myelography (not CT with IV contrast) is the appropriate alternative when MRI is contraindicated, as it assesses thecal sac patency and neural foramina, though it requires lumbar puncture 1, 2