Myelography: modern technique and indications.

Myelography describes the instillation of intrathecal contrast media for the imaging evaluation of spinal canal pathology. The technique has evolved with the use of progressively less toxic contrast agents over its 90-year history and the inclusion of advanced image acquisition technology, including both computed tomography (CT) and magnetic resonance imaging (MRI), in addition to plain radiographic projections. The use of myelography for routine evaluation of spinal disease has diminished greatly due to the advent of MRI which has superior soft-tissue contrast and is relatively non-invasive. However, it is still a critical technique for conventional indications, such as spinal stenosis, when MRI is contraindicated or nondiagnostic. It is also recognized as the study of choice for brachial plexus injury, radiation therapy treatment planning, and cerebrospinal fluid (CSF) leak. Modern myelographic procedural technique and a discussion of how it contributes to these current indications will be reviewed in this chapter.