Which diagnostic test may be ordered to evaluate brain electrical activity after head injury?

Which diagnostic test may be ordered to evaluate brain electrical activity after head injury?

• A. MRI
• B. CT
• C. X-ray
• D. EEG

Answer: (D)

Evaluating brain electrical activity is done with an electroencephalogram (EEG). EEG records the brain’s electrical signals via scalp electrodes and is especially useful after head injury to detect seizure activity, including nonconvulsive seizures, and to assess overall brain function in coma or altered mental status. It reveals patterns like epileptiform discharges or slowing that point to functional disturbances, not anatomy. Imaging tests such as MRI or CT, by contrast, visualize brain structure to identify bleeding, contusions, or fractures, but they don’t measure electrical activity. X-ray isn’t useful for brain evaluation. So, when the goal is to assess electrical activity after head injury, EEG is the most appropriate choice.

Evaluating brain electrical activity is done with an electroencephalogram (EEG). EEG records the brain’s electrical signals via scalp electrodes and is especially useful after head injury to detect seizure activity, including nonconvulsive seizures, and to assess overall brain function in coma or altered mental status. It reveals patterns like epileptiform discharges or slowing that point to functional disturbances, not anatomy. Imaging tests such as MRI or CT, by contrast, visualize brain structure to identify bleeding, contusions, or fractures, but they don’t measure electrical activity. X-ray isn’t useful for brain evaluation. So, when the goal is to assess electrical activity after head injury, EEG is the most appropriate choice.