
Neurophysiology Laboratory
The Neurophysiology Laboratory at Sacramento Imaging offers a wide range of neurodiagnostic testing procedures in two convenient locations, Sacramento Imaging Center in Sacramento and Sacramento Imaging Center in Rancho Cordova.
Testing offered at Sacramento Imaging’s Neurophysiology Lab includes:
- Electroencephalography (EEG)
- Electromyography (EMG)
- Nerve conduction studies (NCS)
- Evoked potential studies (auditory, visual and somatosensory)
Physicians and their patients benefit from the convenience of centralized services so all arrangements can be accomplished with one phone call and multiple testing procedures can be accomplished quickly and in one location.
Electromyography (EMG)
Electromyography (EMG) charts electrical activity in your muscles. This study is useful in providing objective information about neuromuscular and neurosensory function. EMGs may also provide the earliest evidence of return of neuromuscular activity (regeneration), thus helping to determine prognosis. EMGs performed serially provide information regarding disease activity or progression, or treatment effectiveness, and are most often useful to determine:
- Carpel tunnel syndrome
- Thoracic outlet syndrome
- Facial weakness or facial pain
- Guillian Barré Muscular dystrophies, myopathies and polymyositis
- Periodic paralysis
- Peripheral neuropathy
- Radiculopathies
- Trauma

Nerve Conduction Studies (NCS)
Nerve Conduction Studies (NCS) are performed by placing surface electrodes over a particular nerve or a muscle innervated by that nerve, and using electrical stimulation to activate the nerve. When the nerve is stimulated, the patient feels a tingling sensation. A physician specializing in electrodiagnostic medicine evaluates the data collected. Patients referred for NCS testing suffer from nerve conditions, which produce numbness, tingling, pain or loss of sensation, or neurological diseases affecting primarily the peripheral nervous system.
Nerve Conduction Studies (NCS)
Electromyography (EMG) charts electrical activity in your muscles. This study is useful in providing objective information about neuromuscular and neurosensory function. EMGs may also provide the earliest evidence of return of neuromuscular activity (regeneration), thus helping to determine prognosis. EMGs performed serially provide information regarding disease activity or progression, or treatment effectiveness, and are most often useful to determine:
- Nerve Conduction Studies (NCS) are performed by placing surface electrodes over a particular nerve or a muscle innervated by that nerve, and using electrical stimulation to activate the nerve. When the nerve is stimulated, the patient feels a tingling sensation. A physician specializing in electrodiagnostic medicine evaluates the data collected. Patients referred for NCS testing suffer from nerve conditions, which produce numbness, tingling, pain or loss of sensation, or neurological diseases affecting primarily the peripheral nervous system.
- Carpel tunnel syndrome
- Thoracic outlet syndrome
- Facial weakness or facial pain
- Guillian Barré
- Muscular dystrophies, myopathies and polymyositis
- Periodic paralysis
- Peripheral neuropathy
- Radiculopathies
- Trauma

The Evoked Potential (EP)
The Evoked Potential (EP) is a recording of electrical activity from the brain, spinal nerves, or sensory receptors in response to specific external stimulation, whether it be visual, auditory, or sensory stimulation. Electrodes are applied to the scalp and other areas of the body, and a series of stimulations are introduced. A computer then records the neurological responses. Hundreds, sometimes thousands, of responses are received, amplified, and averaged by the computer. The final response is then printed on a graph and interpreted by a physician who looks for particular waveforms and the latency. Evoked Potentials are helpful in evaluating a number of different neurological problems including spinal cord injuries, acoustic neuroma, and optic neuritis. Each type of EP looks at a different neurological pathway.
The most common types of EPs are:
Auditory
The Brainstem Auditory Evoked Potential (BAEP) assists in evaluating the auditory nerve pathways from the ears through the brainstem. Earphones deliver a series of clicks or tones to each ear separately.
Visual
Visual Evoked Potentials (VEPs) evaluate the visual nervous system from the eyes to the occipital (visual) cortex of the brain. The patient is usually asked to look at a pattern on a video screen while remaining fully alert. Each eye is tested separately.
Somatosensory
Somatosensory Evoked Potentials (SSEPs) assess pathways from nerves in the arms or legs, through the spinal cord to the brainstem or cerebral cortex. A small electrical current is applied to the skin overlying nerves on the arms or legs. The current creates a tingling sensation, but is not painful. Each leg or arm is tested separately.

Patient Information
At Sacramento Imaging, we have been exceeding expectations for over 25 years. Our physicians and staff are committed to specifically designing our diagnostic testing based on each patient’s individual clinical concern to help plan the best course of care.
What to Bring to Your Appointment
- Patient Registration/History Form
Frequently Asked Questions (FAQs)
Neuromuscular and Electrodiagnostic Medicine is the study of nerve and muscle diseases. To determine whether your nerves and muscles are working properly. Nerve conduction and Electromyographic tests are ordered. Signs and symptoms that may suggest a neuromuscular disorder include:
- Paresthesias (numbness, tingling, burning, etc.)
- Muscle weakness or atrophy
- Muscle cramps or fasciculations
Learn more below about what to expect during your Nerve Conduction/EMG testing at Sacramento Imaging
You are being sent to the Sacramento Imaging laboratory because you may have numbness, tingling, pain, weakness, or muscle cramping. The doctor will use one or more electrodiagnostic tests to determine if your muscles or nerves are damaged and, if so, how to treat you.
Bring your medication list, picture ID, insurance cards and copay.
Bring related medical records, particularly X-ray, CT, or MRI reports.
Patient form(s)
Adult companion to assist with history and accompany you throughout entire diagnostic testing. If no companion is available we can provide a Medical Assistant upon request.
Allow about 2-4 hours for complete evaluation including wait time. Idea: bring fun reading to pass the wait time. We offer Wi-Fi access.
Call 916- to reschedule or cancel at least 48 hours in advance.
Sacramento Imaging is a provider for Medicare and most major insurance plans. We provide insurance billing. You may be responsible for any amounts not paid by your insurance.
Your insurance company may require you to pay a co-payment at the time of your appointment. When necessary, our staff will work closely with patients who require a payment plan or who don’t have insurance.
If you have any questions regarding which insurance plans we accept or any patient billing concerns, please call us at 916.905.5363. Questions regarding your coverage and benefits should be directed to your employer or insurance company.
There are usually 3 parts to the test visit:
Focused exam by Neuromuscular doctor
Nerve Conduction Studies (NCSs) by certified technician
EMG Testing by physician.
FOCUSED NEUROMUSCULAR EXAM: Our Board-Certified doctor will review your history, notes from your referring doctor, and examine you with a focus on your muscle & nerve function.
NCS TESTING: Our Certified Neurophysiology Technologist applies small electrical shocks to your nerve(s) to study how the nerve works. These shocks cause a quick, mild, tingling feeling. The technologist tests several nerves during your study and our doctor reviews the data and may select additional nerves for diagnostic clarification.
EMG TESTING: Our doctor inserts a new, small, thin needle into several muscles. The doctor is able to hear and see how your muscles and nerves are working. The only muscles tested are those needed to decide what is wrong. There may be a small amount of pain during the study.
Tell the doctor performing the tests if you: take aspirin or blood thinners (like Coumadin), have a pacemaker, or have hemophilia. On the day of the test, take a bath or shower to remove oil from your skin and do not use body lotion. If you have existing conditions, ask your doctor if you should take any medications before the test. Wear sleeveless open collar shirt and loose fitting shorts.
Each study is designed especially for you based on your symptoms and the focused exam performed before your testing. The length of the test is different for every patient. The tests usually take about 1 hour, but please allow up to four hours in your schedule as wait time can vary. You may perform normal activities like eating, driving, and exercising before and after the tests. There are no lasting side effects.
After the tests are complete, our doctor will discuss your test results with you and send them to your referring doctor and other providers as your request. After the examination, you can check with the doctor who sent you to Sacramento Imaging for the next step in your care.
The American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) recommends a medical doctor (MD or DO) who is board certified in neurology or physical medicine and rehabilitation perform this specialized testing. All Sacramento Imaging doctors are certified by the American Board of Psychiatry and Neurology or the American Board of Physical Medicine and Rehabilitation.
Nerves work like electrical wires-they send signals from your body to your brain and your brain to your muscles. Your muscles are the tissues in your body that make you move.
When working properly, the nerves send electrical impulses to the muscles. A nerve disorder means that signals are not getting through like they should. A muscle disorder means that muscles are not responding to the signals correctly.
Please wear a comfortable, sleeveless, open collar shirt and loose-fitting shorts for your testing. Do not apply lotions to the skin. No jewelry or scents.