MRI of the lumbar
spine, with its multiplanar
3 dimensional imaging capability, is currently the preferred modality for establishing a diagnosis.
MRI scans and
magnetic resonance myelography have many advantages compared with computed tomography and/or X-ray myelography in evaluating the lumbar
spine.
MR imaging scans large areas of the
spine without ionizing radiation, is noninvasive, not affected by bone artifacts, provides vascular imaging capability, and makes use of safer
contrast agents (
gadolinium chelate).
Due to the high level of tissue
contrast resolution, nerves and discs are clearly visible.
MRI is excellent for detecting degenerative disease in the
spine. Lumbar
spine MRI accurately shows disc disease (prolapsed disc or slipped disc), the level at which disc disease occurs, and if a disc is compressing spinal nerves. Lumbar
spine MRI depicts soft tissues, including the cauda equina, spinal cord, ligaments, epidural fat, subarachnoid space, and intervertebral discs. Loss of epidural fat on
T1 weighted images, loss of cerebrospinal fluid signal around the dural sac on
T2 weighted images and degenerative disc disease are common features of lumbar stenosis.
Common indications for MRI of the lumbar spine:
•
Neurologic deficits, evidence of radiculopathy, acute spinal cord compression (e.g., sudden bowel/bladder disturbance)
•
Suspected systemic disorders (primary tumors, drop metastases, osteomyelitis)
•
Postoperative evaluation of lumbar spine: disk vs. scar
•
Localized back pain with no radiculopathy (leg pain)
Lumbar
spine imaging requires a special
spine coil. often used whole
spine array coils have the advantage that patients do not need other positioning if also upper parts of the
spine should be scanned.
Sagittal T1 and
T2 weighted FSE sequences are the standard views. With
multi angle oblique techniques individually oriented transverse images of each intervertebral disc at different angles can be obtained.
See also the related poll result: '
MRI will have replaced 50% of x-ray exams by'