Versions Compared

Version Old Version 15 New Version Current
Changes made by

LEHONGRE Katia

LEHONGRE Katia

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

Table of Contents


 

There are different setup to acquire the iEEG with the epileptic patients, using 2 different amplfiers: a clinical one and a reserch one

Characteristics of the amplifiers

Clinical amplifiers

Nicolet (< 2010)

This amplifier has been used from xxxx to xxxx in order to record macroelectrodes

  • maximum number of channels :
  • samplig rate : 400 Hz
  • input range :
  • bandpass

Micromed: SD LTM 64 BS (2010 - July 2020)

This amplifier is used since xxxx in order to record macroelectrodes.

  • maximum number of channels : 128 - 2 boxes of 64 inputs each
  • samplig rate : 1024 Hz
  • input range : +/- 3.2 mV
  • bandpass : 0.18 - 220 Hz

Micromed: SD LTM 64 PLUS (September 2020 - )

This amplifier is used since September 2020 (pat_02968_1239) in order to record macroelectrodes.

  • maximum number of channels : 128 - 2 boxes of 64 inputs each
  • samplig rate : 1024 Hz
  • input range : +/- 3.2 mV
  • bandpass : 0.18 - 220 Hz

Image Added

Research amplifiers

Neuralynx : Lynx (2010 - July 2012)

This amplifier has been used from xxxx 2010 to xxxx July 2010 in order to record only microelectrodes, with Cheetah software

Neuralynx : ATLAS (November 2012 - )

This amplifier is used since October 2012 in order to record microelectrodes and macroelectrodes.

  • maximum number of channels : 160
  • samplig rate : flexible but set to 4kHz for the macroelectrdoes and 32 kHz for the microelectrodes
  • input range : flexible  but set to +/- 4mV
  • bandpass : flexible  but set to 0.1 - 1000 Hz for the macroelectrodes and 0.1 - 8000 Hz for the microelectrodes
  • acquisition software :
    • Cheetah : October 2012 - Mai 2022 (pat_02006_0436 - pat_03152_1614)
      • march 2022: direct RJ45 cable between Neuralynx and Micromed PCs (pat_03138_1601)
    • Pegasus : June 2022 - (pat_03167_1630 - )

 

Image Added



Electrodes

Macroelectrodes

The macroelectrodes (AdTech®, Wisconsin) consist of 4-12 platinum contact electrodes with a diameter of 1.12 mm and length of 2.41 mm, with nickel-chromium wiring. The distance between the center of 2 contacts is 5 mm.

Microelectrodes

The macro-microelectrodes (AdTech®, Wisconsin) are of the Behnke-Fried type, consisting of 8 platinum contact electrodes with a diameter of 1.28 mm and length of 1.57 mm, embedded on the surface of a polyurethane tube with a hollow lumen. Eight 40 µm platinum-iridium microwires were inserted into the macroelectrode, protruding 3-6 mm into the cerebral tissue beyond the tip of the macroelectrode. The protruding microwires were cut to the desired length during the surgical procedure. The distance between contact 1 and 2 is 3 mm, between 2 and 3, 3 and 4, etc is 7 mm.



Connectors

Adtech CABRIO connectors

Those connectors are used for macroelectrodes

Image Added

Neuralynx Headstages CHETs

Those connectors are used for microelectrodes, and can also be used for macroelectrodes

Image Added

Acquisition setups (- macroelectrodes / -- microelectrodes)

setup #1: Clinical setup

Image Modified

 



amplifier:

  • Micromed

electrodes:

  • macroelectrodes

connectors:

  • AdTech

period used

setup #2: Macro and micro electrodes separated

Image Modified

 



amplifier:

  • Micromed
  • Neuralynx

electrodes:

  • macroelectrodes to Micromed
  • microelectrodes to Neuralynx

connectors:

  • CHETs for all electrodes

period used:

setup #3: Macro and micro electrodes together, but 2 amplifiers in parallel

Image Modified

 



amplifier:

  • Micromed
  • Neuralynx

electrodes:

  • macroelectrodes to both systems
  • microelectrodes at least to Neuralynx

connectors:

  • CHETs for all electrodes

period used:

  • start in October 2012
  • end in Apr 2018
  • + 1 patient in november 2018

setup #4: Macro and micro electrodes together, only 1 amplifier, using Neuralynx CHETs

Image Modified

 



amplifier:

  • Neuralynx (sent to Micromed PC)

electrodes:

  • macroelectrodes to both acquisition PC
  • microelectrodes to both acquisition PC

connectors:

  • CHETs for all electrodes
  • TopHat adapters beginning of Apr 2018 (end of recording) and July 2018 (whole recording)

period used:

  • tests March 2018 and June 2018 (whole recording with Nlx//MM in parallel) and July 2018 (whole recording)
  • october 2018
Research system

setup #5: Macro and micro electrodes together, only 1 amplifier, using AdTech connectors

Image Modified

This setup is the classical clinical setup, using the Microimed clinical amplifier in order to record only macroelectrodes. This system is used since xxx and was the only system available until xxxx.



amplifier:

  • Neuralynx (sent to Micromed PC)

electrodes:

  • macroelectrodes to both acquisition PC
  • microelectrodes to both acquisition PC

connectors:

  • AdTech for macroeletrodes + Neuralynx Headboxes
  • CHETs for microeletrodes

period used:

  • tests Jan 2019
  • January 2019- (pat_02680_1158-)

Sleep electrodes

Since february 2017 (pat_02459_0912) scalp electrodes were added in order to record sleep activity. Some of the electrodes (emg and E1, E2) are removed during the week ends

  • O1, Oz, O2
  • E1, E2
  • C3, M2 or C4, M1 for right and left implantation respectively

For the analysis they should be rereferenced as follow

Updates

September 2020

The epilepsy unit moved from Paul Castaigne to Marguerite Bottard.

The Micromed system has been renewed at the same time, but the Neuralynx system remains the same.

The first patient recorded in Margurite Bottard is pat_02968_1239, with the new Micromed system only

March 2022

Direct RJ45 cable installed between Neuralynx and Micromed PCs (first patient: pat_03138_1601)

June 2022

Upgrade of the Neuralynx software from Cheetah to Pegasus and update of Micromed's software.

First patient recorded with the new woftwares: pat_03167_1630

December 2023

The epilepsy moved back to the renew building now called : Institut de Neurologie

First patient recorded : pat_03364_1840