At Tennessee Valley Neurological Associates, our practice encompasses diagnosis and treatment of the following issues (as well as many other neurological disorders) in adults:

• Alzheimer's Disease (and other memory disorders)
• Parkinson's Disease
• Epilepsy
• Stroke
• Multiple Sclerosis
• Peripheral Neuropathies
• Migraines
• Dementia
• Vertigo and Dizziness
• Syncope

Electromyography (EMG) and Nerve Conduction Studies(NCS) are ordered to learn more about the health of  the nerves that travel to and from your hands and feet (called peripheral nerves). These tests measure the speed of the nerve's conductivity and the electrical activity of the nerve to establish if a nerve is working properly. In the case of nerve injury or nerve entrapment, the test can often locate the exact site.

EMG and NCS are often done together to provide more complete information. More specifically:

• A NCS is used to detect and evaluate damage to the peripheral nervous system and to identify the location of abnormal sensations, such as numbness, tingling, or pain.
• An EMG is performed to aid in the diagnosis of conditions that damage muscle tissue, nerves, or the junctions between nerve and muscle (neuromuscular junctions), as well as to evaluate the cause of weakness, paralysis, involuntary muscle twitching, or other symptoms. (Problems in a muscle, the nerves supplying a muscle, the spinal cord, or the area of the brain that controls a muscle can all cause these kinds of symptoms.)

What To Expect

EMG: The muscles are assessed by inserting a tiny Teflon coated pin electrode into the muscle with the computer then recording the muscle potential. The sensation is similar to that of an injection that goes into the muscle as the pin electrode is inserted into the muscle. (That is if sensory awareness is not a problem.) It is important for the patient to lie still to reduce interference and to achieve accurate readings.

NCS: The patient will be asked to lie on an examination table. Electrodes are placed on the skin over the nerve to be studied. These electrodes act as microphones to pick up any electrical signal that goes by them. An electrical stimulator is then placed on the skin near the electrodes and is used to create an electrical current strong enough to fully stimulate the nerve. A computer is used to record responses as various nerves are tested. This allows the physician to measure and calculate how fast the nerve is sending the impulses to the muscle.

• A majority of the time spent with the patient is setting up the studies and running the computer; a very small amount of the time involves electrical stimulation or use of the pin electrode.
• Discomfort during the tests should be minimal. The electrical stimulation of the nerve conduction study could be compared to a static electricity shock. The pin insertion could be compared to being pinched by someone's fingernails.
• No sedation is used during the test, as the patient needs to be awake to follow instructions during the exam.

How To Prepare

1. Please do not wear any lotion or perfume anywhere on the body.
2. Wear loose fitting clothes that can be raised to above the knee or above the elbow, depending on the limb that will be tested.
3. Take all medications regularly, unless given other instructions by your physician.

Following the Exam

• For some, there can be minor irritation at the pin insertion sites.  However,  there are no lasting effects from either the NCS or the EMG.
• The examining physician can give you an idea of any obvious abnormalities at the end of the test the same day. However, more detailed interpretation will be done once the results are factored into the patient's health history, symptoms, physical and neurological examinations, and the results of other tests to help establish a diagnosis.

An electroencephalogram (EEG) is a test to detect abnormalities in the electrical activity of the brain.  At Tennessee Valley Neurological Associates, we are able to perform this test in our facility, as well as for our hospital patients.

An EEG is used to help diagnose the presence and type of seizure disorders, to look for causes of confusion, and to evaluate head injuries, tumors, infections, degenerative diseases, and metabolic disturbances that affect the brain. It is also used to evaluate sleep disorders and to investigate periods of unconsciousness.

What to Expect

In an EEG, electrodes (that look like flat metal discs) are placed on the scalp over multiple areas of the brain to record patterns and check for abnormalities in the tiny electrical impulses brain cells used to communicate.

A trained technician will guide you through the process as the test is performed.

The technician will apply between 16 and 25 electrodes with a sticky paste. These electrodes are connected to an amplifier and a computerized recording machine.

The recording machine converts the electrical signals into a series of wavy lines that are digitally recorded on the computer.

• You will need to be able to lie on your back on a table for the test.
• You will need to lie still with your eyes closed because any movement can alter the results.
• You may be asked to do certain things during the recording, if indicated, such as breathe deeply and rapidly for several minutes, or look at a bright flickering light through closed eyes.
• This test causes no discomfort. While you may notice the feel of the electrodes on your skin, they only record activity and do not produce any sensation.

How to Prepare

1. Wash your hair the night before the test, omitting any oils, sprays, or conditioner that you may usually use in your hair.
2. Take all medications regularly, unless given other instructions by your physician.
3. Sometimes it is necessary to sleep during the test, so you may be asked to reduce your sleep time the night before the test.

Visual evoked responses (VER) evaluate the visual nervous system from the eye to the brain. The test is used to check for optic neuritis, optic tumors, retinal disorders and demyelinating diseases, such as multiple sclerosis.

What to Expect

• The test usually takes around 30 minutes.
• The head is measured and each electrode is attached with electrode paste and a piece of gauze.
• Three or more electrodes are attached to the patient's scalp. The patient is asked to stare at a pattern on a video screen. Each eye is tested separately. A patch is placed over the eye not being tested.
• After the test, the electrodes are removed with warm water and a washcloth. The patient's hair and skin remain intact. Normal washing of the hair will remove any leftover residue from the paste.

Preparing for the Test

1. You will need to be alert and well rested.
2. Bring any glasses or contact lenses you normally use.
3. Take all medications regularly, unless given other instructions by their physician.

After the Exam

The patient will learn the test results from either their neurologist or from a copy of the VER report sent to their referring physician.

The brainstem auditory evoked response (BAER) test measures responses in brain waves that are stimulated by a clicking sound to evaluate the central auditory pathways of the brainstem. The test is performed to help diagnose nervous system abnormalities, hearing losses, and to assess neurologic functions.

What to Expect

• You will be positioned on a reclining chair or bed and asked to relax and remain still.
• Electrodes will be placed on your scalp and on each earlobe.
• You will hear clicking noises or tone bursts through earphones, and the electrodes pick up the brain's response and record it on a graph.
• There is little, if any, discomfort.

How to Prepare

Please wash your hair the night before the test.

Vagus nerve stimulation (VNS Therapy®) is designed to prevent seizures by sending regular, mild pulses of electrical energy to the brain via the vagus nerve, which is part of the autonomic nervous system that controls functions of the body that are not under voluntary control. These pulses are supplied by a device something like a pacemaker.

More details about the procedure may be found at the Epilepsy Foundation website.