From the Guidelines
For numbness in the hand, a noncontrast MRI is usually the most appropriate initial imaging study to order, as it provides improved nerve root definition and is suitable for assessing new or increasing radiculopathy. When considering the best approach for diagnosing the cause of hand numbness, it's crucial to prioritize imaging modalities that can effectively identify compression or damage to the nerve roots in the cervical spine. According to the American College of Radiology Appropriateness Criteria 1, noncontrast MRI is preferred for evaluating new or increasing radiculopathy due to its ability to clearly define nerve roots.
The key points to consider when ordering an MRI for numbness in the hand include:
- The clinical presentation of the patient, with a focus on symptoms such as numbness, tingling, or weakness in the hand.
- The importance of selecting an imaging modality that can accurately assess the cervical spine and its potential impact on nerve roots.
- The role of noncontrast MRI in providing detailed images of the spinal cord, nerve roots, and surrounding structures without the need for contrast enhancement, unless specific conditions such as infection or malignancy are suspected.
In the context of real-life clinical practice, prioritizing noncontrast MRI for initial assessment aligns with the goal of minimizing unnecessary exposure to contrast agents while effectively evaluating the cause of hand numbness. This approach is supported by the most recent and highest quality evidence available 1, which emphasizes the appropriateness of noncontrast MRI for assessing new or increasing radiculopathy.
From the Research
MRI Options for Neck Pain with Numbness in Hand
To determine the appropriate MRI for neck pain with numbness in hand, several factors should be considered:
- The type of MRI sequence used can affect the visibility of certain conditions, such as spinal cord compression or intramedullary lesions 2.
- Dynamic MRI, which includes flexion and extension views, can provide more information about cervical canal stenosis and cord impingement than neutral position MRI alone 2.
- T2-weighted sequences are useful for identifying hyperintense intramedullary lesions, which can be associated with poor neurological outcome 3, 4.
Key Considerations
When ordering an MRI for neck pain with numbness in hand, consider the following:
- A dynamic MRI protocol, including flexion and extension views, may be beneficial for evaluating cervical canal stenosis and cord impingement 2.
- T2-weighted sequences should be included to identify hyperintense intramedullary lesions 3, 4.
- The American College of Radiology has published appropriateness criteria for the use of MRI in evaluating neck pain and cervical radiculopathy, which may be helpful in guiding the decision to order an MRI 5.
MRI Measurements
Several MRI measurements can be useful in assessing cervical spinal canal stenosis, including:
- Cord-canal-area ratio
- Space available for the cord
- Compression ratio 6 These measurements can help identify patients at risk for acute cervical spinal cord injury and can be used to evaluate the severity of spinal canal stenosis.