Neurodiagnostics
At St. Mary's of Michigan, we offer a series of special diagnostic procedures that help us study and record the electrical activity in the brain and nervous system. Highly qualified registered technologists perform the procedures. Specially trained physicians interpret the results. We then send a report of the findings to your physician, who will use the information to treat you in the most appropriate way.

Neurodiagnostic testing requires an order from a physician. To schedule an appointment, call (989) 907-1959. A St. Mary's of Michigan associate will let you know the exact location where your test will performed. If you need driving directions, click here.

Electroencephalogram (EEG) - estimated time 60-90 minutes
An EEG records the electrical activity in your brain. It is often used to help manage seizure disorders or for evaluating headaches, dizziness, strokes, or degenerative brain diseases.

For the patient, the test is not painful. A technician measures your head and places electrodes on your scalp. We will ask you to remain still, relaxed, and comfortable during the test. We may occasionally ask you to take repeated deep breaths and look at a strobe light. Both of these activities can help reveal different brain patterns that are useful for a diagnosis.

Sometimes, physicians want to observe brain patterns that occur during sleep. For sleep tests, we will ask you to stay awake most of the night prior to your EEG appointment and may give you a mild sedative.

If your doctor prescribes a 24-hour ambulatory EEG, you will wear the electrodes on your scalp and carry a small tape recorder-like device around your waist. While at home for 24 hours, we will ask you to record your activities and any symptoms in a diary.

EEG Preparation
Please wash your hair before coming in. Do not use any hair spray or oil. If you are taking any medication, continue to do so unless your doctor tells you not to. Wear comfortable clothes, as it is important for you to be as relaxed as possible during the test. Young children may bring a favorite blanket or small toy.

Electromyography (EMG) - estimated time 30 minutes per extremity
An EMG records the electrical activity within a muscle. It is used to detect and diagnose pinched nerves or nerve damage due to injury, ruptured disc, or other causes.

Physicians perform this test by inserting two tiny needles into the muscles being tested. You may feel some temporary, mild discomfort. You will be lying down during the test, since normal and abnormal findings are easier to locate in relaxed muscles. You may talk and ask questions during the examination. You will hear something that sounds like static, which is your muscle activity being recorded and shown on a screen.

EMG Preparation
There is no special preparation. You may take your normal medications, including pain medication. If you are on a blood thinner or have a cardiac pacemaker, please mention this to the physician prior to the test.

Nerve Conduction Study (NCS)
An NCS is typically performed by a technician prior to an EMG. It is done by giving your nerve a weak electrical stimulation. Electrodes placed on your skin are used to record the response. This is helpful in diagnosing various nerve disorders such as carpal tunnel and diabetes neuritis in the arms, legs, or back.

Patients usually have a slight, temporary prickling feeling during the test.

NCS Preparation
There is no special preparation. You may take your normal medications, including pain medication. If you are on a blood thinner or have a cardiac pacemaker, please mention this to the physician prior to the test.

Evoked Potentials (EP)
An EP is a recording of electrical activity from the brain, spinal nerves, or sensory receptors in response to specific external stimulation. EPs are helpful in evaluating a number of different neurological problems, including multiple sclerosis, head injuries, spinal cord injuries, acoustic neuromas, and optic neuritis.

A technician applies electrodes to your scalp and other areas of your body. The electrodes introduce a series of stimuli, and the neurological responses are recorded. Hundreds of responses are received, amplified and averaged by a computer. The final response is plotted on a graph and interpreted by a physician who looks for particular waveforms and the time it takes them to occur.

Each type of EP looks at a different neurological pathway. The three most common are the brainstem auditory evoked response (BAER), visual evoked response (VER), and somatosensory evoked response (SSER).

Brainstem Auditory Evoked Response (BAER) - estimated time 30 minutes
The BAER helps in evaluating the auditory nerve pathways from the ears through the brainstem. We attach electrodes to your scalp and earlobes. Then, we place earphones over your ears. The phones deliver a series of clicks or tones to each ear separately.

Visual Evoked Response (VER) - estimated time 30 minutes
VERs evaluate the visual nervous system from the eyes to the occipital (visual) cortex of the brain. We apply electrodes to your scalp and ask you to stare at a pattern on a video screen while remaining fully alert. We test each eye separately.

Somatosensory Evoked Response (SSER) - estimated time 60 minutes
SSERs assess pathways from nerves in the arms or legs, through the spinal cord, to the brainstem or cerebral cortex. We place electrodes on your scalp and along the spinal cord. A small electrical current is then applied to the skin overlying nerves on the arms or legs. The current creates a tingling sensation but is not painful. We test each leg or arm separately.

EP Preparation
Please wash your hair before coming in. Do not use any hair spray or oil. If you are taking any medication, continue to do so unless your doctor tells you not to. Wear comfortable clothes, as it is important for you to be as relaxed as possible during the test. Young children may bring a favorite blanket or small toy.