Electro-Encephalography.pptx

kursk state medical university

1. Electro-Encephalography Swami Keshav (Group 9, 2 nd year 3 rd semester) Kursk state medical university Repalova Natalia Vladimirovna Detail physiology of CNS

2. Electroencephalography  ( EEG ) is a method to record an  electrogram  of the electrical activity on the  scalp  that has been shown to represent the macroscopic activity of the surface layer of the  brain  underneath. It is typically non-invasive, with the  electrodes  placed along the   scalp .  Electrocorticography , involving invasive electrodes, is sometimes called intracranial EEG.

3. EEG measures voltage fluctuations resulting from  ionic current   within the  neurons  of the  brain .  Clinically, EEG refers to the recording of the brain's spontaneous electrical activity over a period of time, as recorded from multiple  electrodes  placed on the scalp.

4. Band Frequency (Hz) Delta < 4 Theta ≥ 4 and < 8 Alpha ≥ 8 and < 14 Beta ≥ 14 Rhythm The rhythmic activity is divided into bands by frequency.

5. DIAGNOSIS An EEG is a  test that detects abnormalities in your brain waves , or in the electrical activity of your brain. During the procedure, electrodes consisting of small metal discs with thin wires are pasted onto your scalp. The electrodes detect tiny electrical charges that result from the activity of your brain cells. Two measurements are commonly used to analyse an EEG record: amplitude, or size of the waves, number of waves per second

6. An EEG might also be helpful for diagnosing or treating the following disorders: Brain tumor. Brain damage from head injury. Brain dysfunction that can have a variety of causes (encephalopathy) Inflammation of the brain (encephalitis) Stroke. Sleep disorders.

7. ADVANTAGES Non – invasive & harmless Lower costs Portable High Temporal Resolution

8. DISADVANTAGES High noise ratio Not very exact measuring Skull weakness the electrical activity Low spatial resolution

9. Спасибо !!