What is the most important test used in determining seizure classification?

The most important test used in determining seizure classification is the electroencephalogram (EEG). The EEG measures electrical activity in the brain, capturing the specific waveforms that occur during seizures. This is critical for differentiating between types of seizures, as different seizure disorders can present with distinct patterns on the EEG. For instance, generalized seizures often show bilateral, synchronous activity, whereas focal seizures may exhibit localized activity.

In contrast, while imaging studies like CT and MRI can identify structural abnormalities that might be causing seizures, they do not provide real-time information regarding electrical activity. Blood tests can help rule out metabolic causes of seizures but do not contribute directly to seizure classification itself. Therefore, the EEG is indispensable in accurately classifying the nature of seizures and guiding appropriate management.