When you accidentally place ECG leads on a patient's scalp, an electroencephalogram (or EEG) is what happens. In this event, an EEG records electrical activity of the brain, which in medical students can be tremendously active but in interns be laden with flat lines. The EEG is noninvasive in that electrodes are placed along the scalp. The gold standard EEG involves placing electrodes directly onto the brain itself. An EEG is typically used to diagnose seizures, though on occasion it may be ordered for atypical presentations of C. diff, cellulitis, pneumonia, and urinary tract infection.
What an EEG Tells You
Nothing. A neurologist reads it, says there are no seizure foci, but also says there are nonspecific changes consistent with infectious, toxic, or metabolic etiologies, which is what you already knew in the first place. Gee, thanks, Neuro.