From the Guidelines
For a patient with a history of two cervical spine fusions presenting with new onset pain and radiculopathy, MRI of the cervical spine is the best initial imaging modality. This recommendation is based on the superior intrinsic soft-tissue contrast and good spatial resolution of MRI, which makes it the preferred method to evaluate the cervical spine in the setting of suspected nerve root impingement 1. The ability of MRI to correctly predict lesions, as reported by Brown et al, with an accuracy of 88% 1, further supports its use as the initial imaging choice.
When considering the best approach for imaging in this context, several factors come into play:
- The need for detailed visualization of neural structures, disc herniations, and potential causes of radiculopathy such as nerve root compression.
- The importance of distinguishing between scar tissue and recurrent disc herniation, which can be achieved with contrast enhancement 1.
- The limitations of other imaging modalities, such as CT myelography, plain myelography, and CT, which have lower accuracy rates compared to MRI 1.
In the clinical management of such patients, it's also crucial to consider the following:
- Plain radiographs should be obtained initially to assess hardware position and alignment.
- Dynamic flexion-extension X-rays may be useful to evaluate for adjacent segment disease or pseudarthrosis.
- The imaging should encompass the entire cervical spine to account for potential pathology at the fusion sites or adjacent levels.
Given the evidence from the study published in the Journal of the American College of Radiology in 2019 1, MRI of the cervical spine stands out as the most appropriate initial imaging modality for patients with a history of cervical spine fusions presenting with new onset pain and radiculopathy, due to its superior diagnostic capabilities and the critical need to accurately assess neural structures and potential causes of radiculopathy in this patient population.
From the Research
Imaging Modalities for Cervical Spine
The best imaging modality for the cervical spine in a patient with a history of two cervical spine fusions presenting with new onset pain and radiculopathy is a topic of discussion among medical professionals.
- MRI is preferred as the initial diagnostic test due to its noninvasive nature and ability to visualize the spinal cord and nerve roots in two planes 2.
- MRI is better in detecting unsuspected pathology at other cervical segmental levels, but its quality can be subject to variation, sometimes not clearly visualizing anticipated pathology 2.
- CT-myelogram can be useful in cases where MRI results are ambiguous or technically suboptimal, particularly in diagnosing foraminal stenosis and bony lesions 3.
- CT studies can better define ossification/calcific changes contributing to stenosis, including OPLL and/or OYL 4.
- 3D MR/CT fusion images can provide a detailed visualization of the path, position, and pathological changes of the cervical nerve roots and spinal root ganglion relative to the cervical bony structure, which can be useful in diagnosing cervical radiculopathy 5.
- CT without or with the use of intrathecal metrizamide was more accurate than myelography in the identification of lesions that caused cervical radiculopathy 6.
Comparison of Imaging Modalities
- MRI and CT-myelogram have similar intraobserver and interobserver agreement, but CTM is better in diagnosing foraminal stenosis and bony lesions, while MRI is better in detecting disc abnormality and nerve root compression 3.
- The choice of imaging modality depends on the specific clinical scenario and the availability of imaging techniques 2, 3, 4, 5, 6.