1. Electrocorticography
ECoG

2. ECoG ??? Recording electrical signal in brain How? Searching what?
Placing electrodes on surface of the brain
Craniotomy or Burr holes
Searching what?
Epileptic zones
What is that?
Epileptic seizers

3. Why not EEG???
Resource :

4. History at a glance
1930 – Dr. Wilder Penfield developed “Montreal Procedure” to detect “auras”
1948 – Rudolf M. Hess conducted first scalp EEG
1949 – Hugo Krayenbuhl and Hess first attempt ECoG
1950 – Herbart Jasper and Dr. Wilder combined both to develop ECoG method

5. Functions Electrode placement Monitoring Signal acquirer Electrodes
g.USBamp
Filtering

6. Clinical usage Where this is being used?
Pre surgical planning
Evaluating the success of the surgery
For research aspects
Flexible in stimulating and recording signal
but
Limited field of view and influence of anesthetic

7. Limitations Spontaneous brain activities Seizures are rarely recorded
Needs quick decisions
Limited sampling time
Limited field of view
Influence of anesthetics

8. Two forms Extra-operative ECoG Intra-operative ECoG

9. Two forms… (ctd) Extra-operative ECoG Before a resectioning
EEG and MRI is also used
Structural lesion
Identifying exact place

10. Two forms… (ctd) Intra-operative ECoG While resectioning
Monitor alleged tissue
Localizing critical zones

11. Research applications
Brain Computer Interface
Neural signal interface
Hybrid invasive
Reference -

12. Specifications Typical time for an investigation? 40 min
Investigating time period?
1- 2 weeks
Temporal resolution?
5 ms
Spatial resolution?
1 cm

13. Safety concerns
Invasive
Minor mistakes but Major cost

14. Risk Assessment Maintenance Strategy Worksheet Clinical function
Physical risk
Problem avoidance probability
Incident history
Manufacturer requirement

15. Any questions?