Electroencephalography (EEG) basics for sleep physician. Part of a talk during Ain Shams Congress of Psychiatry, 2012. Cairo, Egypt

1. Electroencephalography basics
for sleep study
Egypt’s early career psychiatrists (EECP) workshop
Ahmed Eid el-Aghoury
Board-certified, MScMed, MBChB
Technical training at Neurovirtual corporation, Florida, USA
al-Abbassia Hospital for mental Health, Cairo

2. Stage?
Cairo, Mar 2012 ajhuri@gmail.com 2

3. Objectives
 Sleep stages
 Key descriptive terms of EEG
 Common normal EEG pattern during
sleep and wake
Cairo, Mar 2012 ajhuri@gmail.com 3

4. Analysis of polysomnogram (PSG)
 The clinical interpretation of PSG is
based primarily on the analysis of 3
main variables:
1) EEG-related variables (i.e., sleep stage,
arousals)
2) Respiration-related variables (i.e.,
apneas or hypopneas)
3) Movement-related variables (i.e.,
periodic leg movements).
Cairo, Mar 2012 ajhuri@gmail.com 4

5. Frequency bands
Cairo, Mar 2012 ajhuri@gmail.com 5

6. Rules of polarity
Channel 1 – 2 ?
Channel 2 – 1?
Cairo, Mar 2012 ajhuri@gmail.com 6

7. Frequent descriptive terms
 Morphology: waveform & polarity
 Amplitude: voltage
 Symmetry: equal amplitudes
 Frequency: CPS / Hz
 Synchrony: simultaneous
 Rhythmicity: similar waveforms
 Distribution / topography: lobes, focal, etc
 Manner: continuous, intermittent, etc
 Duration: in ms
 Maturation: age
 Reactivity: eye closing, calculation, etc
 Burst: paroxysm, run or train of activity
Cairo, Mar 2012 ajhuri@gmail.com 7

8. AASM Scoring Manual, 2007
Iber C, Ancoli-Israel S, Chesson A, Quan SF for the American Academy of Sleep Medicine:
The AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and
Technical Specifications, 1st ed. Westchester, IL: American Academy of Sleep Medicine,
2007.
Cairo, Mar 2012 ajhuri@gmail.com 8

9. Sleep Stage Nomenclature
Berry R: Fundamentals of sleep medicine. 2012, Elsevier Saunders, PA
Cairo, Mar 2012 ajhuri@gmail.com 9

10. Summary of Important Wave
Form Characteristics
Berry R: Fundamentals of sleep medicine. 2012, Elsevier Saunders, PA
Cairo, Mar 2012 ajhuri@gmail.com 10

11. The recommended EEG derivations:
F4-M1, C4-M1, and O2-M1. (AASM, 2007)
Cairo, Mar 2012 ajhuri@gmail.com 11

12. Background Activity
 Syn: occipital alpha rhythm / dominant
posterior rhythm / DPR / ODR
 The starting point for visual analysis
 Around 10 Hz: ( 8 – 13 Hz)
 Frequency milestones (maturation): eg
by age 2 ys (7 - 8 Hz )
 Tested by passive eye closure
 Slow & Fast variants
Cairo, Mar 2012 ajhuri@gmail.com 12

13. Stage W
Cairo, Mar 2012 ajhuri@gmail.com 13

14. Drowsiness
 Syn: hypnagogic state
 A “presleep state”, or a “prodromal or
twilight condition” between being fully
awake and asleep :
 Background activity can be 1 to 2 Hz
less than that for wakefulness
Cairo, Mar 2012 ajhuri@gmail.com 14

15. Drowsiness
Cairo, Mar 2012 ajhuri@gmail.com 15

16. Hypnagogic hypersynchrony
Cairo, Mar 2012 ajhuri@gmail.com 16

17. Two years boy: eyes close &
open
Cairo, Mar 2012 ajhuri@gmail.com 17

18. Stage N2
Cairo, Mar 2012 ajhuri@gmail.com 18

19. V waves: stage?
Cairo, Mar 2012 ajhuri@gmail.com 19

20. Stage N3
Cairo, Mar 2012 ajhuri@gmail.com 20

21. Stage R
Cairo, Mar 2012 ajhuri@gmail.com 21

22. Stage R
Cairo, Mar 2012 ajhuri@gmail.com 22

23. Cairo, Mar 2012 ajhuri@gmail.com 23

24. 14 & 6 positive burst: comb-like
Cairo, Mar 2012 ajhuri@gmail.com 24

25. Cairo, Mar 2012 ajhuri@gmail.com 25

26. Cairo, Mar 2012 ajhuri@gmail.com 26

27. An elder man: stage?
Cairo, Mar 2012 ajhuri@gmail.com 27

28. Cairo, Mar 2012 ajhuri@gmail.com 28

29. ECG artifact: stage?
Cairo, Mar 2012 ajhuri@gmail.com 29

30. Cairo, Mar 2012 ajhuri@gmail.com 30

31. Stage N2 / N3 ?
Cairo, Mar 2012 ajhuri@gmail.com 31

32. Is this epileptiform?
Cairo, Mar 2012 ajhuri@gmail.com 32

33. Is this epileptiform?
Cairo, Mar 2012 ajhuri@gmail.com 33

34. Cairo, Mar 2012 ajhuri@gmail.com 34

35. DPR: wax & wane. Stage?
Cairo, Mar 2012 ajhuri@gmail.com 35

36. Asleep: stage? Age?
Cairo, Mar 2012 ajhuri@gmail.com 36

37. First slide again: Stage?
Cairo, Mar 2012 ajhuri@gmail.com 37

38. Thanks to neurovirtual for
material & training
Cairo, Mar 2012 ajhuri@gmail.com 38