Neurodiagnostic Testing

Neurology

What is an EMG test?

EMG or Electromyography is a test that is used to study the nerve and muscle function. EMG testing can provide your doctor with information about the extent and type of nerve and muscle disease/injury and can also determine the location of injury and give some indication whether the damage is reversible. more

What is an EMG test?

There are 2 parts to EMG testing: a nerve conduction study (NCS) and a needle exam for muscle testing.

What to expect during EMG testing?

The NCS part of EMG involves stimulating the nerves at different points with small electric shocks, artificially activating them so their function can be measured. The shock may feel like a rubber band snapping on the skin. The shocks can cause some discomfort but are usually well tolerated by most people.

The needle exam part of EMG involves inserting very fine needle into several muscles to record electrical signals. There is some discomfort at the time the needle electrodes are inserted. They feel like shots (intramuscular injections), although nothing is injected during an EMG. Afterwards, the muscle may feel a little sore. The needles used are disposable and immediately disposed of following use.
Does EMG testing hurt?
The EMG involves stimulation of nerves with mild electric current and needle insertion in various muscles. Both parts may result in some discomfort but are usually well tolerated by most people.
How long does the EMG test take?
EMG testing usually takes anywhere from 40-120 minutes, depending on the condition being tested and findings of the study.
What are the preparations for the EMG test?
There are no special preparations for an EMG test.

There is no need to fast. You can eat and drink before the test.

Try to avoid applying any lotion or creams because that can cause some difficulties during the testing.

Patients on medication should take their usual medication on the day of the test unless otherwise advised by their physician.

Patients on anticoagulation or blood thinners and those with pacemakers and implanted defibrillators should notify the physician performing the test so that necessary precautions can be taken during testing.
Are the needles used for EMG reusable?
No. The needles used are disposable and immediately disposed of following use.
Which part of EMG is done by a technologist?
The nerve conduction study (NCS) part is either done by a physician or a trained EMG technologist under the supervision of the physician. The needle examination part is only done by a physician.

What is EP test?

EP or Evoked potential, is a test that is used to measure the electrical activity in certain areas of the brain and spinal cord. Electrical activity is produced by stimulation of specific sensory nerve pathways. The Evoked potentials measure how quickly and completely the nerve signals reach the brain. more

What is EP test?

EP or Evoked potential is a test that is used to measure the electrical activity in certain areas of the brain and spinal cord. Electrical activity is produced by stimulation of specific sensory nerve pathways. The Evoked potentials measure how quickly and completely the nerve signals reach the brain. less

There are 4 types EPs:
Median nerve somatosensory EPs: They are also called as upper limb SSEPs or MSEP. This test involves application of electrodes on the scalp, neck, above the collar bone, and the wrists. The Median nerve is stimulated at the wrist with very mild electric current. The electric current feels like mild shocks. The shocks are usually painless and well tolerated by most people but may cause some discomfort for some patients. This test may take 30-60 minutes to complete.

Tibial nerve somatosensory EPs: They are also called as Lower limb SSEPs or TSEP. This test involves application of electrodes on the scalp, back, knee, and the ankles. The Tibial nerve is stimulated at the ankle with very mild electric current. The electric current feels like mild shocks. The shocks are usually painless and well tolerated by most people but may cause some discomfort for some patients. This test may take 30-60 minutes to complete.

Visual Evoked Potentials or VEP: This test involves application of electrodes on the scalp. The visual pathway are stimulated by looking at a changing checkerboard pattern on a video monitor. This test may take 30-60 minutes to complete.

Auditory Evoked Potential or BAER or AEP: This test involves application of electrodes on the scalp. The hearing sensory pathways are stimulated by clicking noises generated in a set of headphones. This test may take 30-60 minutes to complete.
How long do the 2 SSEPs take?
60-90 minutes
How long do all 4 EP tests take?
2 -21/2 hours.
What are the preparations for the EP test?

Try to avoid applying any lotion or creams because that can cause some difficulties during the testing of SSEPs. Also, avoid using hair gel, because it interferes with scalp electrodes.

Patients on medication should take their usual medication on the day of the test unless otherwise advised by their physician.

Please bring eyeglasses, if you use them, for the Visual EP.

What is an EEG test?

The EEG is a test that is used to study brain wave patterns. It can provide your doctor with information about the nature of the type of difficulties you’ve been experiencing. more

What is an EEG test?

The EEG is a test that is used to study brain wave patterns. It can provide your doctor with information about the nature of the type of difficulties you’ve been experiencing. less

What to expect during EEG testing?
A specially trained EEG technician will first measure your head with a tape measure. He will then rub certain spots on your scalp lightly, and place about 20 gold disk electrodes with a light cream on those spots. You will be asked to recline in a chair or lay in a bed for about one half hour while a special machine records your brain waves. During the sessions, you may be asked to breathe in and out deeply and lights may be flashed before you with your eyes closed.
Does EEG testing hurt?
The EEG does not involve needles or electrical stimulation of any kind. It is a completely painless procedure.
What are the preparations for the EEG Test?

Tell your doctor if you are taking any medications. Certain medications (such as sedatives and tranquilizers, muscle relaxants, sleeping medications, and medications used to treat seizures) can affect your brain’s electrical activity. Patients on medication should take their usual medication on the day of the test.

Since a deep breathing exercise (hyperventilation) may be performed, please inform the technologist of any hearing or respiratory issues, sickle cell anemia, recent head trauma, or stroke.

Avoid foods that contain caffeine (such as coffee, tea, cola, and chocolate) for at least eight hours before the test. Otherwise, you can eat and drink as usual before the test.

Your hair should be clean and free of sprays, oils, creams, lotions, and other hair preparations. Shampoo your hair and rinse with clean water the evening before or the morning of the test. Do not apply any hair conditioners or oils after shampooing. Do not braid or tease the hair. This test cannot be performed on patients with non-removable weaves or wigs.

After the EEG, the cream and discs will be removed by the technologist. Small reddened areas may be noted on the scalp which will disappear in a short period of time.

Allow 60-120 minutes for this procedure.
What to expect during the appointment:

The EEG is completely painless

Small, disc-shaped cups will be placed on your head to record the electrical activity of the brain.

The discs will be secured with a small amount of paste and tape/gauze, all of which will be washed away quickly after the test is complete.

The technologist will ask the patient to relax and attempt to go to sleep.

The EEG will be read by the physician after you leave the office. You should expect results via phone or mail within five business days.

If you have any questions regarding the EEG procedure or wish to cancel/reschedule, please call 212.606.1047.