1 MRI OF THE CERVICAL SPINE . Michael Wilczynski, DO FAOCR Donald Kim, DO. Diagnostic Radiology Department Chair Radiology Residency, St James Healthcare Franciscan St James Healthcare Abdominal Imaging Fellowship, UCSF. Chicago, IL. CLINICAL INDICATIONS. Absent or reduced sensation on clinical examination Absent or reduced reflexes Muscle wasting Severe intractable arm pain where symptoms have been present for more than 6 weeks CERVICAL radicular pain persisting for greater than 6 weeks Axial neck pain persisting for greater than 3 months Reduced power on physical examination CNS Tumor, Infection, Inflamation Tumor of the meninges Congenital malformations of the spinal cord, including vascular malformations Spinal surgery follow up Trauma CERVICAL RADICULOPATHY WORKUP.
2 Plain radiography Radiography of the CERVICAL SPINE is usually the first diagnostic test ordered in patients who present with neck and limb symptoms More often than not, this study is diagnostic of CERVICAL disc disease as the cause of the radiculopathy The American College of Radiology recommends plain radiographs as the most appropriate initial study in all patients with chronic neck pain Lateral, anteroposterior, and oblique views On the lateral view Look for disc-space narrowing, comparing the level above and below Typically, the CERVICAL disc spaces get larger from C2-C6, with C5-C6 being the widest disc space in normal necks, and C6-C7 slightly narrower. Besides narrowing, look for subchondral sclerosis and osteophyte formation.
3 On oblique views Look for foraminal stenosis at the level of the suspected radiculopathy, comparing it with the opposite foramina CERVICAL RADICULOPATHY WORKUP. Plain radiography Other views: An open-mouth view should be ordered to rule out injury to the atlantoaxial joint when significant acute trauma has occurred If C7 can not be properly seen, then a "swimmer's view" (supine oblique view, in which the patient's arm is extended over the head). The atlantodens interval (ADI) is the distance from the posterior aspect of the anterior C1 arch and the odontoid process. This interval should be less than 3 mm in adults and less than 4 mm in children An increase in the ADI suggests atlantoaxial instability, such as from trauma or rheumatoid arthritis.
4 Flexion and extension (lateral) views can be helpful in assessing spinal mobility and stability Limitations Problems with both specificity and sensitivity exist Correlations of findings on plain radiographs and cadaver dissections have found a 67% correlation between disc-space narrowing and anatomic findings of disc degeneration However, radiographs identified only 57% of large posterior osteophytes and only 32% of abnormalities of the apophyseal joints that were found on dissection NORMAL. CERVICAL RADICULOPATHY WORKUP. CT of the CERVICAL SPINE CT scanning provides good visualization of bony elements and can be helpful in the assessment of acute fractures It can also be helpful when C6 and C7 cannot be clearly seen on traditional lateral radiographic views The accuracy of CT imaging of the CERVICAL SPINE ranges from 72-91% in the diagnosis of disc herniation.
5 CT with contrast myelography Has an accuracy approaching 96% for diagnosis of CERVICAL disc herniation The addition of contrast material allows for the visualization of the subarachnoid space and assessment of the spinal cord and nerve roots Even with myelography, however, soft-tissue visualization with CT is inferior to that provided by magnetic resonance imaging (MRI). NORMAL DJD (also C2 fracture). CERVICAL RADICULOPATHY WORKUP. MRI. The American College of Radiology recommends routine MRI as the most appropriate imaging study in patients with chronic neck pain who have neurologic signs or symptoms but normal radiographs. MRI has become the method of choice for imaging the neck to detect significant soft-tissue pathology, such as disc herniation MRI can detect ligament and disc disruption, which cannot be demonstrated by other imaging studies The entire spinal cord, nerve roots, and axial skeleton can be visualized MRI has been found to be quite useful in evaluating the amount of cerebrospinal fluid (CSF) surrounding the cord in the evaluation of patients with CERVICAL canal stenosis, although the T2-weighted images tend to exaggerate the degree of stenosis.
6 Although MRI is considered the imaging method of choice for the evaluation of CERVICAL radiculopathy, abnormalities have also been found in asymptomatic subjects. In one study, 10% of subjects younger than 40 years, were noted to have disc herniations 20% of subjects older than 40 years, had evidence of foraminal stenosis and 8% had disc protrusion or herniation Therefore, as with all imaging studies, the MRI findings must be used in conjunction with the patient's history and physical examination findings. NORMAL Disc bulges and DJD. MRI CONTRAINDICATIONS. It is necessary to update continuously knowledge regarding the safety issues related to MR technology, as well as to the technology of implants, devices, contrast agents, and other aspects related to the magnetic resonance imaging (MRI) examination MRI has become an increasingly used imaging modality in many fields of medicine, including cardiovascular imaging.
7 Therefore, careful patient screening before the examination, accurate evaluation of the individual risk, and qualified patient supervision is mandatory Most reported cases of MR related injuries and the few fatalities that have occurred have apparently been the result of failure to follow safety guidelines or from the use of inappropriate or outdated information related to the safety aspects Be aware of your radiology department requirements, as many strictly require documentation of any devices or clips MRI SAFETY RESOURCE. STANDARD C- SPINE SEQUENCES. T1-weighted Axial Sagittal T2-weighted Axial Sagittal STIR or T2 fat sat Sagittal Gradient Echo Axial (T1 post contrast, if needed).
8 C- SPINE MRI APPROACH. Basic principles are same for the lumbar SPINE C- SPINE MRI APPROACH: ABCDE. A. B. C. D. E. C- SPINE MRI APPROACH: ABCDE. Alignment Bone Cord/Canal Discs Everything else C- SPINE MRI. APPROACH. Alignment Anterior portion of vertebral bodies Posterior portion of vertebral bodies Facets Posterior spinal canal line Spinous processes 28-year-old man with atypical hangman's fracture. C2 body fracture with anteroposterior displacement of fracture fragments (fat C2 body sign) is seen. Fracture disrupts Harris ring posteriorly and causes posterior offset of spinolaminar line from C1 to C3 (dotted line). Bilateral interfacetal dislocation. 50% anteroposition C5-C6 as a result of the dislocation.
9 In unilateral dislocation the anteroposition is usually only 25%. Widened space between spinous processes C5 and C6 due to ligament rupture. Ruptured disc space. Notice on the axial image that the cord injury is located in the grey matter, which is more sensitive to damage. Soft tissue swelling anteriorly Disruption of the disc Non-hemorrhagic cord injury C- SPINE MRI APPROACH. Bone Fractures Vertebral body compression Blastic or lytic lesions FLEXION INJURIES. THE MOST COMMON FRACTURE MECHANISM IN CERVICAL INJURIES IS HYPERFLEXION. ANTERIOR SUBLUXATION OCCURS WHEN THE POSTERIOR LIGAMENTS RUPTURE. SINCE THE ANTERIOR AND MIDDLE COLUMNS REMAIN INTACT, THIS FRACTURE IS STABLE.
10 SIMPLE WEDGE FRACTURE IS THE RESULT OF A PURE FLEXION INJURY. THE POSTERIOR. LIGAMENTS REMAIN INTACT. ANTERIOR WEDGING OF 3MM OR MORE SUGGESTS FRACTURE. INCREASED CONCAVITY ALONG WITH INCREASED DENSITY DUE TO BONY IMPACTION. USUALY. INVOLVES THE UPPER ENDPLATE. UNSTABLE WEDGE FRACTURE IS AN UNSTABLE FLEXION INJURY DUE TO DAMAGE TO BOTH THE. ANTERIOR COLUMN (ANTERIOR WEDGE FRACTURE) AS THE POSTERIOR COLUMN. (INTERSPINOUS LIGAMENT). UNILATERAL INTERFACET DISLOCATION IS DUE TO BOTH FLEXION AND ROTATION. BILATERAL INTERFACET DISLOCATION IS THE RESULT OF EXTREME FLECTION. UNSTABLE AND IS. ASSOCIATED WITH A HIGH INCIDENCE OF CORD DAMAGE. FLEXION TEARDROP FRACTURE IS THE RESULT OF EXTREME FLECTION WITH AXIAL LOADING.