10 20 system of eeg

Electrode placement-10-20 systems

BY -RAKESH KUMAR

MAJOR LAND MARK

Nasion-base of nose where nasal and frontal bone unite.

Inion - prominent point on occipital protuberance

MAJOR LAND MARK

MAJOR LAND MARK

CC

Auricular points Is just anterior to the tragus at root of helix

Central point Cz localization

First a measurement is taken from Nasion to Inion

CC

Second measurement from one tragus to other side tragus


Cz-intersection point of the AP and coronal measurement

cz


Anterior to posterior measument

zz

z

z

The first measurement is in the anterior-posterior plane through the vertex, taken from the Nasion to the Inion.


zz

z

z

1

This AP Measurement divided into 5 segments- Fp,Fz,Cz,Pz,Oz


zz

z

z

2



zz

z

z

3



zz

z

z

4



zz

z

z

1

5



zz

z

z

The first mark is placed at 10% posterior to Nasion of the total measurement and labelled Fp.

zz

z

z

z

The second, third, fourth and fifth marks are placed at 20% intervals of the total measurement and label Fz, Cz, Pz, and Oz .


zz

z

z

z

zz

The second, third, fourth and fifth marks are placed at 20% intervals of the total measurement and label Fz, Cz, Pz, and Oz .


Lateral measurement of the central coronal plane starts at the left preauricular point, Just anterior To tragus through the Cz to the right preauricular point.

Coronal measurement

Coronal measurement

Lateral measurement of the central coronal plane starts at the left preauricular point, Just anterior To tragus through the Cz to the right preauricular point.

A mark is placed at 10% of this measurement from the preauricular points and labelled T3 on left and T4 on right

Coronal measurement

Coronal measurement

A mark is placed at 10% of this measurement from the preauricular points and labelled T3 on left and T4 on right

A mark is placed in that line of 20 % of total length on both side are marked C3 and C4 from T3 and T4 respectively..

Coronal measurement

Circumferential measurement

A circumferential measurement is then taken over the temporal lobes from the midline Fp position to the midline O position through T3 and T4 in left and right side respectively.


T4


A mark is 10 % from Fp to either side as Fp1 and Fp2.

Fp2

A mark is 10 % from Fp to either side as Fp1 and Fp2.


F8

Fp2

20 % of total length at that line from Fp1 and Fp2 is F7 in Left and F8 in right


20 % of T3 and T4 at same line are T5 and T6 left and right side


T6

T4

20 % of T3 and T4 at same line are T5 and T6 left and right side


O2

10% from Oz in left is O1 and right is O2


Para sagittal measurement

Intersection point of the Fp1 to C3 and F7 to Fz is F3 in left.

intersection point of the Fp2 to C4 and Fz to F8 is F4 in right


Intersection point of the C3 and O1 and T5 and Pz is P3 in left


intersection point of the C4 and O2 and T6 to Pz is P4 in right


Extra electrodes in NIMHANST1,T2


Line is drawn from tragus to outer cantus to both side

Line is drawn from tragus to outer canthus to both side


1/31/3

A point is taken on this line that is 1/3 of total length from tragus to outer canthus


1 cm 1 cm

Point is taken from 1 cm vertical from this point on that horizontal line



1 cm 1 cm

T2 T1

This mark is final for T2 in right side and T1 in left side

Extra electrodes in NIMHANSF9 &F10

FFFP9

F8F7


FZFZ

A line is drawn from F8 to F7 that is passing through Fz

FFFP9

F8F7

FZFZ

10%10%

Vertical downward a point is taken from F7 and F8 this is 10% of total measurement from F8 to F7,on each side


FFFP9

F8F7


FZFZ

10%

F9F10

10%

This final point on each side are F9 and F10 in left and right Respectively

10 20 system of eeg

Education