The EDX examination is a test that measures the electrical activity in your nerves and muscles. It consists of two parts:
- Nerve conduction studies that measure the ability of specific nerves to transmit electrical impulses, or messages, to muscles.
- Needle electrode examinations that measure the electrical activity in muscles along nerves..
Measuring the electrical activity in nerves and muscles helps detect the presence, location and extent of nerve and muscle disorders. Muscle weakness, nerve pains, and numbness may be due to a problem in the brain, spinal cord, the nerve supplying the muscle, the junction between the nerve and muscle (called the neuromuscular junction) and muscle. The EDX examination can help physicians distinguish where the problem lies.
You will be asked to lie on an examination table. The technician will tape several small, flat metal discs, called electrodes, on your skin. Repeated brief electrical stimuli are administered to the nerve. Electrical waveforms are recorded from muscles or from nerves and measured. You will feel a tingling sensation and twitching in your muscle each time the electrical stimulus is applied. Once the testing has been completed, the skin electrodes are removed.
The nerve conduction studies are then followed by the needle examination by the physician. A small thin needle (about the size of a straight pin) attached by wires to a recording machine will be inserted in the specific muscles being examined. No electrical stimuli or injections are passed through this needle; they simply record your muscle activity. You will be asked to relax and contract the muscles that are being examined. The electrical activity of the muscle will be displayed as electrical waves on a screen that the physician will view. The more relaxed you are, the easier the tests will be. The physician and technician will try to make you as comfortable as possible.
Before the EDX Examination
This test should not be performed until at least three weeks (21 days) have passed since the onset of your symptoms. If it has been less than that, please notify the EMG lab at 216.444.5544, or toll free 1.800.CCF.CARE ext.45544. You may be asked to reschedule at a later date.
- Take medications as prescribed, including any for pain.
- If you are taking anticoagulant medications (coumadin, heparin, lovenox, or crystalline warfarin) or medication for myasthenia gravis (mestinon or pyridostigmine bromide) and have not received instructions from your physician to discontinue your medications for the EDX examination, please call 216.444.5544 or toll free 1.800.223.2273 ext.45544. You may be asked to discontinue these medications for several days before the test. However, DO NOT discontinue medications without first consulting your physician.
- The EDX examination cannot be performed on patients with a bleeding disorder or lymphedema.
- Nerve conduction studies cannot be performed on patients with internal defibrillators. If you have an internal defibrillator and have been scheduled for this test, please call 216.444.5544 or toll free 1.800.223.2273 ext.45544. It will be necessary to assess whether the device can be turned off prior to undergoing this test.
- Patients with internal nerve stimulators must be able to turn them off before nerve conduction studies can be performed If you have an internal nerve stimulator and have been scheduled for this test, please call 216.444.5544.
On the Day of the Test
Eat a normal breakfast and/or lunch. Do not apply any lotions or oils to the skin; it could hinder the electrode connection to the skin.
After the Test
The Neuromuscular Staff evaluates the data collected and the final report is sent to the doctor who referred you for the test (usually between 1-2 working days). Your doctor will provide you with the results.
Neurology appointment office 216.636.5860, or toll free 1.800.CCF.CARE ext.65860.
Desk S90, Ninth floor of the “S” building.
Please call the EDX Laboratory if you have any concerns or questions or wish to speak to a technician: 216.444.5544, or toll free 1.800.CCF.CARE ext.45544.