What is EMG?

Electromyography (EMG) is a diagnostic procedure that evaluates the health and function of muscles and the nerve cells that control them. By applying an electrical current during the EMG procedure, it is possible to measure the electrical conduction functions of the nerves and the electrical potential generated by muscle activity. EMG is commonly used in the diagnosis of neuromuscular disorders, nerve dysfunction, and muscle diseases.

When Should EMG Be Performed?

EMG is recommended in the following conditions:

  • Nerve injuries (e.g., stabbing, gunshot wounds, compression injuries)
  • Metabolic conditions such as diabetes, folic acid, and vitamin B12 deficiency
  • Neurological diseases such as poliomyelitis and amyotrophic lateral sclerosis (ALS)
  • Peripheral nerve disorders such as carpal tunnel syndrome and cubital tunnel syndrome
  • Spinal disorders including herniated discs and cervical hernia
  • Facial paralysis
  • Birth-related nerve injuries in newborns
  • Muscle diseases requiring diagnostic confirmation

Preparation for an EMG Procedure

  • For a needle EMG, patients should have a meal beforehand to avoid discomfort.
  • Comfortable, loose-fitting clothing should be worn to facilitate movement and examination.

Electroencephalography (EEG)

What is EEG?

Electroencephalography (EEG) is a diagnostic technique used to assess the electrical activity of the brain. Neurons within the brain generate electrical signals, which are transmitted to the scalp. EEG detects these signals, helping to diagnose and monitor neurological conditions.

How is EEG Performed?

  • Electrodes are attached to the scalp and sometimes earlobes using a special adhesive paste.
  • These electrodes do not send electricity into the brain; they only record electrical activity.
  • The collected brain waves are displayed on a monitor for analysis.
  • EEG can be performed while the patient is awake or asleep, depending on the physician’s assessment.
  • The electrical activity of the brain varies between wakefulness and sleep, aiding in the diagnosis of specific disorders.

Preparation for an EEG Procedure

  • Patients must have clean hair before the procedure, as dirty or oily hair can interfere with accurate signal recordings.
  • No substances such as hair gel, oil, or cream should be applied to the scalp before the test.

When Should EEG Be Performed?

EEG is crucial in diagnosing and monitoring conditions such as:

  • Epilepsy (to detect abnormal brain wave patterns indicative of seizures)
  • Head trauma following accidents or injuries
  • Brain dysfunction disorders such as encephalopathy
  • Brain tumors (to assess abnormal electrical activity)
  • Brain inflammation (e.g., encephalitis)
  • Stroke (paralysis) monitoring and diagnosis
  • Sleep disorders such as insomnia and narcolepsy
  • Psychiatric disorders such as schizophrenia and bipolar disorder
  • Neuropsychiatric conditions affecting cognition and mood
  • Memory problems and dementia, including Alzheimer’s disease

Frequently Asked Questions (FAQs) About EMG and EEG

EMG FAQs

Does EMG hurt?

  • There may be slight discomfort during the needle insertion, but it is generally well tolerated.

How long does an EMG take?

  • Depending on the area being tested, it usually takes 30 to 60 minutes.

Are there any risks with EMG?

  • EMG is a low-risk procedure, but minor bruising or soreness may occur at the needle insertion sites.

Can I take my medications before EMG?

  • Inform your physician about all medications, but most can be continued as usual.

What do EMG results indicate?

  • Abnormal results may suggest nerve damage, muscle disease, or a neurological disorder requiring further evaluation.

EEG FAQs

Is EEG painful?

  • No, EEG is completely painless.

How long does an EEG take?

  • It typically lasts 30 to 60 minutes, but extended recordings may be required for certain conditions.

Can I eat before EEG?

  • Yes, eating is allowed, but avoid caffeine as it may affect brain activity.

Will EEG detect all brain abnormalities?

  • EEG detects electrical abnormalities but may not reveal structural issues such as tumors. MRI or CT scans may be required for further assessment.

Can I take medications before an EEG?

  • Inform your doctor about any medications, as some drugs may need to be paused before testing.