In the past several years, tremendous advances in technology and instrumentation have dramatically changed diagnostic testing. Today's sophisticated tests can provide an intricately detailed visualization of tissue and bone structure that previously could only be seen through open surgery. Preoperative imaging for spinal conditions and problems may include plain x-rays of the neck, mid-back, or lower back as well as dynamic views including flexion/extension to see if there is instability. Magnetic resonance image scans may be taken of the cervical, thoracic, and lumbar spine. Myelograms and post-myelogram CAT scans of the specific area in question may also be used to arrive at a diagnosis. Intraoperative films are taken to help make intraoperative decisions and to localize the areas of concern. New image-guided spinal navigation systems are available for complex problems, making intraoperative surgical decisions better and safer for patients.

Electrodiagnostic studies including electromyography and nerve conduction velocities (EMGs and NCVs) can localize the nerve dysfunction pattern and help make the correct diagnosis in cases where there can be two separate problems affecting the same nerve. 

Click on a Keyword below for more information on these imaging techniques. X-ray MRI Myelogram CAT Scans EMG NCV

X-ray

An x-ray is a commonly used imaging technique that uses low-levels of radiation and special film to visualize problem areas. During an x-ray, the skin is exposed to radiation. The radiation is absorbed by dense parts of the body, like bone, which shows up white on the x-ray. Less dense areas of the body absorb less radiation and show as darker images on the film.

MRI

Magnetic resonance imaging (MRI) is a relatively new area of imaging that combines magnetic fields, radio frequencies, and computer technology to produce a virtual slice of human anatomy. The slices are electronically brought together with a computer to give a detailed visualization of affected areas.

The body is made of atoms. The center of the atom is made of nuclei that spin at different angles. When the nuclei are exposed to the powerful magnet used in MRI, they begin spinning at the same angle. A radio signal is transmitted and the alignment of the nuclei is changed. When the radio signal stops, the nuclei return to their aligned position and release a slight radio frequency of their own. This frequency is measured and visualized by the computer.

Myelogram

A myelogram is an x-ray of the spinal cord, nerve roots, and other tissues in the spinal canal. During the procedure, a contrast agent is injected into the lower back. The patient lays on a specially designed table which tilts in various directions to direct the dye to areas that need to be imaged. The images are then visualized on a computer screen.

CAT Scans

This diagnostic technique combines the computer and x-rays that pass through the body at different angles to create images of thin slices of the tissue in question. The images provide a clear picture of soft tissue, including tumors and fluid-filled spaces called ventricles. The slices can be brought together electronically to form a three-dimensional visualization of the area being examined.

EMG

The electromyogram records electrical impulses generated in the muscles through small electrodes placed on the skin or by needles inserted into the muscle. The muscle is evaluated during contraction and rest. The impulses can be produced on an oscilloscope and heard through a speaker. This diagnostic tool is used to help diagnose muscle disorders such as muscular dystrophy, and also disorders that involve impaired nerve supply to the muscle.

NCV

Nerve conduction velocity testing is used to diagnose conditions that affect nerve function. The NCV uses surface electrodes and mild electrical impulses to measure the speed of nerve conduction and the strength of the action potential in the nerve. The nerve response is then visualized on an oscilloscope and heard through a speaker.