Which invasive test combines fluoroscopy and radiography to evaluate the spinal subarachnoid space and uses contrast medium injected into the epidural space by spinal puncture?

Which invasive test combines fluoroscopy and radiography to evaluate the spinal subarachnoid space and uses contrast medium injected into the epidural space by spinal puncture?

• A. X-ray
• B. Fluoroscopy
• C. Venography
• D. Myelography

Answer: (D)

Visualizing the spinal subarachnoid space with contrast under real-time imaging is the key idea. This invasive test, called myelography, involves injecting contrast through a spinal puncture into the spinal canal and then using fluoroscopy to guide imaging, followed by radiographs to show how the contrast outlines the thecal sac and nerve roots. The contrast makes the subarachnoid space stand out against the surrounding tissues, so abnormalities such as herniated discs or compressive lesions become visible. Other options either image without targeted contrast or focus on other structures (for example, X-ray alone lacks the dynamic contrast view of the subarachnoid space, fluoroscopy by itself doesn’t specify the subarachnoid space, and venography maps veins rather than the spinal canal). Myelography was a common technique before newer MRI and CT methods provided noninvasive cross-sectional detail.

Visualizing the spinal subarachnoid space with contrast under real-time imaging is the key idea. This invasive test, called myelography, involves injecting contrast through a spinal puncture into the spinal canal and then using fluoroscopy to guide imaging, followed by radiographs to show how the contrast outlines the thecal sac and nerve roots. The contrast makes the subarachnoid space stand out against the surrounding tissues, so abnormalities such as herniated discs or compressive lesions become visible. Other options either image without targeted contrast or focus on other structures (for example, X-ray alone lacks the dynamic contrast view of the subarachnoid space, fluoroscopy by itself doesn’t specify the subarachnoid space, and venography maps veins rather than the spinal canal). Myelography was a common technique before newer MRI and CT methods provided noninvasive cross-sectional detail.