From the Guidelines
To rule out a herniated disc in the lower back, a lumbar spine MRI without contrast is typically the most appropriate imaging study to order. This type of MRI provides detailed images of the spinal discs, nerves, and surrounding structures in the lower back, allowing for clear visualization of disc herniations, nerve compression, and other potential causes of back pain. The non-contrast version is usually sufficient for evaluating disc pathology, as herniated discs can be clearly seen without the need for contrast enhancement. The MRI should include both T1 and T2 weighted sequences, as well as axial and sagittal views to properly evaluate the disc spaces and neural foramina. In some cases, if there is concern for infection, tumor, or post-surgical changes, a contrast-enhanced MRI might be considered, but for initial evaluation of suspected disc herniation, non-contrast imaging is the standard approach. This imaging modality is preferred over CT scans because MRI better visualizes soft tissue structures like intervertebral discs and the spinal cord, providing superior diagnostic information for disc-related conditions, as supported by the American College of Radiology Appropriateness Criteria 1.
Some key points to consider when ordering an MRI for suspected herniated disc include:
- The MRI should be performed without contrast initially, unless there are specific concerns that would necessitate the use of contrast, such as infection or tumor, as noted in the guidelines 1.
- The imaging protocol should include T1 and T2 weighted sequences, as well as axial and sagittal views, to provide a comprehensive evaluation of the spinal discs and surrounding structures.
- MRI is preferred over CT scans for evaluating disc-related conditions due to its superior visualization of soft tissue structures, as recommended by the American College of Physicians and the American Pain Society 1.
Overall, a lumbar spine MRI without contrast is the most appropriate initial imaging study for ruling out a herniated disc in the lower back, providing valuable diagnostic information to guide treatment decisions.
From the Research
MRI for Diagnosing Herniated Disk of Lower Back
To rule out a herniated disk of the lower back, the following types of MRI can be ordered:
- Lumbar spine MRI without contrast to evaluate the intervertebral discs, nerve roots, and spinal canal 2, 3
- Lumbar spine MRI with contrast to evaluate the intervertebral discs, nerve roots, and spinal canal, and to assess for any enhancement of the disc or surrounding tissues 3
Key Considerations
When ordering an MRI to diagnose a herniated disk of the lower back, consider the following:
- MRI is a non-invasive and highly sensitive diagnostic tool for evaluating lumbar disc herniation 2, 3
- MRI can provide detailed images of the intervertebral discs, nerve roots, and spinal canal, allowing for accurate diagnosis and treatment planning 4, 5
- The choice of MRI sequence and protocol may depend on the specific clinical question and the patient's symptoms and medical history 5
Comparison with Other Diagnostic Tests
Compared to other diagnostic tests, such as myelography and CT scans, MRI has been shown to be a more accurate and sensitive diagnostic tool for evaluating lumbar disc herniation 2, 3, 6. Specifically: