Electroencephalogram (EEG) Testing
Electroencephalogram (EEG) is a test performed to detect abnormalities related to electrical activity of the brain. This is a noninvasive procedure, where electrodes are placed along the scalp. The electrical brain activity can be recorded for extended periods of time. This may last 30 minutes with or without sleep deprivation, 24 hours, 72 hours or continuous for a certain amount of time. Special electrodes may also be placed to record electrical activity deeper in the brain. It can detect and localize abnormal electrical parts of the brain. It is a functional test that can enhance diagnosis of abnormalities seen on a CT scan or MRI.
This test is useful in evaluating transient episodes of shaking, confusion, dizziness, language disturbance, numbness, or weakness.
An EEG may be helpful for diagnosing or treating the following disorders:
- Epilepsy or other seizure disorder
- Brain tumor
- Head injury
- Brain dysfunction that may have a variety of causes
- Sleep disorders
An EMG is a study that measures the electrical activity of nerves and muscles. Both tests are usually performed together. The nerve conduction component is a non-invasie procedure in which electrodes are placed on the skin. The nerve is given an electrical impulse. The nerve conduction of the impulse is measures the function of the nerve and can tell where an injury occurred and severity of the injury. The EMG portion is a needle examination of the muscle. It measures the activity of the muscle at rest and contracted. It can also measure the severity of nerve and muscle injury.
Purpose of EMG/NCV Tests
The test is helpful is evaluating nerve pain or neuralgia, muscle weakness or pain, numbness, and tingling.
An EMG is helpful in diagnosing or treating the following disorders:
- Carpal Tunnel Syndrome
- Cervical Radiculopathy
- Muscular Dystrophy
- Myasthenia Gravis
- Peripheral Neuropathy
Botulinum toxin is a neurotoxin produced by the bacterium Clostridium botulinum. The sterile, purified toxin can be injected into several different muscles or under the skin to paralyze muscles or nerves. The effect can last 3-12 months. There are 4 different types of botulinum toxins that the FDA approved for use in the United States.
Botox (onabotulinium A) is FDA approved for 9 different diseases. It was first improved in 1989 for the use of strabismus, blepharospasm and hemifacial spasm. It is most commonly used by neurologists for the treatment of blepharospasm, cervical dystonia, chronic migraine, and upper and lower limb spasticity. The most common side effects are pain, and swelling at the site of the injection. There can be serious side effects of swallowing difficulty and difficulty breathing, particularly when injected in the neck for cervical dystonina.
Myobloc (rimabotulinum toxin B) is approved for cervical dystonia. It was FDA approved in 2000. It is the only toxin B. It is particularly useful for patients who are resistant to Botox or Dysport.
Dysport (abobotulinium A) is also approved for cervical dystonia as well as limb spasticity. Dysport was FDA approved in 2009. Botox and Dysport are both botulinum toxin A. The difference is the manufacturing and non-protein toxins. There may be a difference in the onset and the duration of the two forms. The doses are not similar. The indications for injection are also not similar.
Xeomin (incobotulinum toxin A) was approved in 2010 for the use in cervical dystonia and blepharospasm. In 2015, it was approved for the use in upper limb spasticity.
Dr. Linda Pao has extensive clinical experience using botulinum to treat the neurological conditions of blepharospasm, cervical dystonia, chronic migraines, and upper and lower limb spasticity since 1993. She has also used this in hyperhidrosis and sialorrhea.
As a Neurologist, Dr. Linda Pao is highly specialized trained to read and interpret neurodiagnostic imaging including MRI, CT, SPECT/PET imaging of the brain and spine. During your one on one patient evaluation, Dr. Linda Pao will review these images personally with each patient. She relies on her colleagues, radiologist, neuro-radiologist, and interventional radiologists who are board certified to officially interpret the imaging.