Electrodiagnostics

At UT Southwestern Medical Center, physical medicine and rehabilitation physicians might prescribe one or more electrodiagnostic examinations to determine how muscle or nerve damage might be contributing to a patient’s symptoms. 

Our team is committed to helping patients achieve the highest possible level of physical, functional, and cognitive independence after an injury or illness, and we are a major referral center for patients requiring rehabilitative care.

Measuring Electrical Activity in the Body

Electrodiagnostic examinations measure electrical activity generated by muscles and nerves. They generally involve seeing how different parts of the body react to stimuli.

Depending on the patient’s condition, a UT Southwestern physician might order one or more electrodiagnostic examinations to determine how muscle or nerve damage might be contributing to symptoms such as numbness, pain, or weakness. Some of the most commonly prescribed electrodiagnostic tests include an EMG exam, a nerve conduction study, and an evoked potential study. 

Electrodiagnostic Services

Electrodiagnostic tests offered at UT Southwestern include:

• Auditory evoked potential (AEP): Auditory signals are transmitted to the ears to detect hearing problems.
  
• Brainstem auditory evoked response (BAER): Auditory signals are transmitted to the ears to detect brain stem problems.
  
• Electroencephalography (EEG): Electrodes (electrical measuring devices) are attached to the scalp to measure brain functions.
  
• Electromyography (EMG): Surface electrodes are placed on the skin or tiny needle electrodes are inserted into muscle to measure activity in the muscle.
  
• Electroretinogram (ERG): Anesthetic drops are placed in the eyes, and electrodes are used to detect a loss of cells in the retina.
  
• Nerve conduction studies (NCS): Electrodes are used to measure activity in the nerves.
  
• Somatosensory-evoked potential (SEP): EEG electrodes measure the brain’s response to a stimulus applied to the skin.
  
• Visual-evoked potential (VEP): EEG electrodes measure the brain’s response to a flash of light or a visual pattern.

Conditions We Treat

Electrodiagnostic testing can help diagnose the following conditions:

• Amyotrophic lateral sclerosis (Lou Gehrig’s disease)
• Epilepsy
• Movement disorders
• Multiple sclerosis
• Nerve conduction
• Neurophysiology
• Parkinson’s disease
• Sleep disorders
• Spinal cord injury
• Stroke

Electrodiagnostic Testing: What to Expect

Most electrodiagnostic testing is painless and quick. Patients having an electromyographic (EMG) test might feel only brief and mild discomfort as the physician inserts a tiny needle into various muscles. The needles are used only to record electrical activity in the muscles and not to deliver any treatment.