Specialized testing helps differentiate neurological conditions from other conditions with similar symptoms. Data from these tests helps our physicians determine an accurate diagnosis to begin appropriate treatment.
Our neurodiagnostic testing includes:
- EMG Nerve Conduction Velocity Test
- EEG and long-term EEG monitoring
- Transcranial Dopplers
- Evoked Potentials
- Intraoperative Monitoring
Electromyography or EMG
Electromyography (EMG) is a test that assesses the health of the muscles and the nerves controlling the muscles. In an EMG, a needle electrode is inserted through the skin into the muscle. The electrical activity detected by the electrode is displayed on an oscilloscope and may be heard through a speaker. After placement of the electrodes, the patient may be asked to contract the muscle (for example, by bending the arm). The wave form produced on the oscilloscope provides information about the ability of the muscle to respond when the nerves are stimulated. EMG testing helps to differentiate primary muscle conditions from muscle weakness caused by neurological disorders.
Nerve Conduction Velocity Test
A nerve conduction velocity test is usually performed in conjunction with an EMG. This test evaluates the speed of conduction of impulses through a nerve. The nerve is stimulated, usually with electrodes that are placed on the skin. One electrode stimulates the nerve with a very mild electrical impulse. The resulting electrical activity is recorded by the other electrodes. The distance between electrodes and the time it takes for electrical impulses to travel between electrodes are used to calculate the nerve conduction velocity. This test is used to diagnose nerve damage or destruction. Abnormal results can indicate peripheral neuropathy, damage to the spinal cord and other conditions.
Electroencephalogram or EEG
An electroencephalogram (EEG) is a test to detect abnormalities in the electrical activity of the brain. Brain cells communicate by producing tiny electrical impulses. In an EEG, electrodes are placed on the scalp over multiple areas of the brain to detect and record patterns of electrical activity and check for abnormalities. An EEG test is used to help diagnose the presence and type of seizure disorders, head injuries, tumors, infections, degenerative diseases, causes of confusion and metabolic disturbances that affect the brain. Inpatient video-EEG monitoring is used to localize seizure onset in patients undergoing evaluation for epilepsy surgery. It is also used to confirm an epilepsy diagnosis.
A transcranial doppler is an ultrasound procedure that shows blood flow through the cerebral vessels via a small probe placed against the skull. This is a portable test, which can be performed at a patient's bedside to follow the progress of medical treatment for stroke.
Evoked potential tests measure the transmission of electrical signals within the brain and spinal cord. It is used to diagnose multiple sclerosis (MS), since MS symptoms are similar to those of other conditions and can also vary considerably across patients.
Intraoperative monitoring involves the testing and interpretation of electrophysiologic measurements of neural function, nerve conduction velocity and electromyography during neurosurgical and spine surgery procedures in order to monitor the integrity of the brain and spinal cord function.
All tests are conducted by qualified and certified staff, and are interpreted by neurologists so that we can provide the most appropriate care for our patients.
For more information about our neurodiagnostic testing services, please contact (727) 725-6451.