Brain death is one of the most serious diagnoses aneurologistcan make.
Unlike severe forms of coma, a diagnosis of brain death meansthere is no coming back.
Medically, brain death is death.
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However, there are times when meeting all the technical qualifications for brain death is impossible.
In these cases, additional testing is called for.
Electroencephalography (EEG)
AnEEGis used to measure electrical activity in the brain.
It is most commonly used when a doctor is concerned that someone has seizures orepilepsy.
The absence of these signals indicates that the brain is no longer able to receive these messages.
This allows for close examination of how blood is moving through the body.
In brain death, the vessels of the brain do not fill as they normally would.
Transcranial Dopplers
A transcranial doppler exam uses ultrasound waves to evaluate blood flow in the brain.
These changes in blood flow can be seen in the transcranial doppler.
Nuclear Medicine Tests
Nuclear medicine involves the injection of a radioisotope into the brain.
This isotope is a chemical that moves along with blood flow.
In a brain death exam, the most common isotope is called technetium-99m hexamethylpropyleneamine oxime.
If the patient is brain dead, then there will be no signal from the brain in the scan.
This is sometimes known as the “hollow skull phenomenon.”
Some technical standards may vary from state to state and even hospital to hospital, however.
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