What imaging modality is best for suspected cauda equina syndrome?

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

Answer: (C)

The best imaging modality for suspected cauda equina syndrome is MRI. This condition involves compression of the cauda equina, a bundle of nerve roots located at the lower end of the spinal cord, which can lead to significant neurological deficits.

MRI is particularly advantageous because it provides high-resolution images of soft tissues, allowing for the direct visualization of the spinal cord, nerve roots, and surrounding structures. It can effectively identify the underlying causes of cauda equina syndrome, such as herniated discs, tumors, or other lesions compressing the neural elements. The sensitivity of MRI to detect changes in the spinal canal and the condition of the nerve roots makes it the preferred choice for diagnosis.

In contrast, while CT scans are useful in certain scenarios due to their faster acquisition times and detail in bony structures, they are less effective than MRI in visualizing soft tissue and nerve root involvement. X-rays primarily assess bony abnormalities and may miss the critical soft tissue pathologies leading to cauda equina syndrome. Ultrasound is not typically utilized for this purpose as it does not penetrate bone effectively and lacks the resolution needed to examine the spinal canal and nerve structures adequately.