The Electrodiagnostic Consultants of Nashville provide a wide variety of electrodiagnostic services designed to assist in the diagnosis and treatment of a breadth of neurological and neuromuscular disorders. These procedures are harmless, though they can be uncomfortable. Listed below is a few of the services we provide.
Nerve cells carry small electrical signals to control muscle cells. Using specialized machinery, we are able to measure the “speed” of these signals through a nerve fiber. Small electrodes are placed on the skin with tape and conductive gel, and then a small stimulation is supplied, a little “shock”- similar to the static sensation of walking across a carpet and touching a metal object. The sensation is uncomfortable, but generally not very painful, and it is very brief. The clinician may ask you to move around as the test continues to access various nerves along the body, and we encourage you stay as relaxed as possible to ease the testing process.
Muscle cells are controlled by nerve cells in small clusters called motor units. If nerve function is disrupted, these muscle cells may “disconnect” from the nerve cells, and may begin to contract independently or react abnormally. An EMG is designed to detect this abnormal muscle behavior. After the skin is cleansed, electrodes are placed on the surface of the skin, and a thin and flexible needle electrode is inserted directly into the affected muscles- the clinician then measures to see if there is any abnormal electrical activity within the muscle. This needle is ordinarily not very painful, but can be quite uncomfortable, depending on the sensitivity of the area.
An EEG uses electrodes on the scalp to measure the activity in certain parts of the brain. In certain conditions like epilepsy or sleep disorders, abnormal electrical activity can be detected in the “signal” given off by collections of nerve cells in brain tissue. Many electrodes are placed onto the scalp with a conductive paste to allow the electrodes to pick up electrical signals through the skin. The clinician will often ask you to watch a probing light, or to breathe quickly for a certain amount of time. You may also be asked to stay awake the night before your test to assist in the diagnostic process. The EEG lasts around one hour, and is painless.
A standard EEG lasts around one hour- for some people, this is enough time to detect abnormal electrical activity within the brain. However, clinicians and neurologists may request or require longer periods of monitoring to detect that abnormal activity. A technician will place the electrodes onto the scalp and create a secure headwrap to ensure those electrodes stay affixed to the head. Specialized equipment is then sent home with the patient so that continuous brain activity may be monitored over a long period of time- this is often done with intermittent video monitoring as well. This duration of the test can vary in length, but is typically around three days- and while the electrodes or headwrap may become uncomfortable, it is typically a painless procedure.
While less common, these examinations still provide key insights into certain rarer neurological conditions that affect both the central and peripheral nervous system. Evoked Potentials measure central nervous system response to stimuli, and can involve watching a blinking screen (Visual Evoked Potentials or VEP), listening to repetitive clicking through a set of headphones (Auditory Evoked Potentials or AEP), or small shocks similar to NCV (Somatosensory Evoked Potentials, or SSEP). This can be used to detect demyelination in the brain and spinal cord, often linked to disorders such as Multiple Sclerosis (MS). The Jolly Test is used to test the neuromuscular junction (NMJ)- it requires very quick repetitive shocks to muscles to detect disorders where muscle cells interact with nerve cells. This is a key diagnostic test for disorders such as Myasthenia Gravis that affect the NMJ. Both of these tests involve electrodes on the skin, and can be uncomfortable, though Visual and Auditory Evoked Potentials are harmless.
We provide various other services as a general neurological clinic, such as formal neurological consultations and treatments, and Botox injections for conditions such as migraines, blepharospasm (uncontrollable blinking or spasming of the eyelids), hemifacial spasms, tarticolis (uncontrollable twisting of the neck), and dystonia, which is a disorder characterized by uncontrollable muscle contractions. If you have any questions regarding what we offer, feel free to reach out!
The information obtained in the Electrodiagnostic Laboratory will be collected. interpreted, and read by either a referring physician or one of our board certified neurologists. It is then applied clinically to the patient’s particular case and medical history. If you are arriving to our office from another practice to have electrodiagnostic testing performed, we will often leave the interpretation of the data to your referring physician.
