Spinecare Topics
Medical Imaging of the disc and spine
New and potentially useful functional imaging strategies used to assess the spine and the intervertebral disc include dynamic computed tomography, dynamic magnetic resonance imaging, functional magnetic resonance imaging, diffusion imaging, and magnetic resonance spectroscopy. Magnetic resonance spectroscopy (MRS) is used to evaluate the biochemical makeup of tissues, kind of an MRI biopsy.
Before the development of noninvasive imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI), techniques that employed the use of contrast material included myelography, epidural venography, and epidurography. These procedures were performed in carefully selected patients with back pain to help determine whether they were a good good candidate for surgery. As imaging techniques have improved the search is on for other sources of back and extremity pain.
CT and MRI currently provides excellent detail of disc herniations and their relationship to the spinal cord and spinal nerves. Routine studies performed without special protocols can not confirm how things are working or where the source of pain is. The demonstration of disc degeneration with these studies does not tell whether it is the cause of back pain.
Several MR-based techniques now available provide functional information that may be useful in patients with back pain. With MR imaging the unique movement of water molecules in tissues can be tracked and measured. Because tissue structure determines the direction and magnitude of water diffusion, diffusion imaging may be used to examine the structure of spinal tissues. Diffusion-weighted imaging and its more sophisticated form, diffusion tensor imaging (DTI), can be applied to the study of the spinal cord or intervertebral disc.
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