Various medical conditions can
result in seizures. Before diagnosing epilepsy, a physician will
consider other possible causes of the seizures. A high fever or a
metabolic disturbance could cause seizures to occur. For example, an
electrolyte disturbance as a result of severe diarrhea or vomiting, or a
glucose imbalance cause by low blood sugar, may result in seizures.
Blood tests are sometimes used to find medical conditions, other than
epilepsy, that may be causing seizures.
In addition to a thorough physical examination, the procedures used to establish a diagnosis of epilepsy usually includes a medical history and diagnostic tests.
Medical history is important in a physician's assessment. Typically, it involves a family health history and a detailed description of the characteristics, onset and frequency of the seizures. Determining the type of seizure an individual is having is valuable in both the diagnosis and the prescribing of the appropriate treatment.
Diagnostic tests usually include an electroencephalogram (EEG). An EEG is used to record the brain's electrical activity and it is an important tool in the diagnosis of epilepsy. Neuroimaging tests are often used to provide pictures of the brain. Computed tomography (CT) and magnetic resonance imaging (MRI) scans provide pictures of the brain structures.
Other neuroimaging tests such as magnetic resonance spectroscopy (MRS) and positron emission tomography (PET) show how the brain functions and are used to evaluate the possibility for epilepsy surgery.
It is important to note that sometimes a diagnostic test does not detect abnormalities. For example, a person with epilepsy may have a normal EEG because abnormal activity is not present during the recording, or the activity is too deeply located in the brain to be recorded.
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