EEG 102 10-20 System of Measurement and Application Techniques

Course Goals and Objectives

During this course, the learner develops the basic skills necessary to measure a head using the International 10/20 System of Electrode Placement and accurately apply a standard set of electrodes to a mannequin or human head.

Lesson 1 The International 10-20 System of Electrode Placement

  • Explain the importance of the International 10/20 System, and the theory behind it
  • Correctly identify each of the anatomical landmarks used to measure a head for the 10/20 system
  • List the name of each electrode location designated in the 10/20 system

Lesson 2 Step-by-Step Measurement Instructions

  • List the supplies needed to measure a mannequin or human head
  • Use a tape measure to measure the distance between the nasion and the inion and correctly mark the appropriate 10% and 20% increments
  • Use the tape measure to measure the distance between the left and right pre-auricular points and correctly mark the appropriate 10% and 20% increments
  • Accurately place a tape measure to measure the head circumference, intersecting the 10% marks above the nasion, inion and preauricular points
  • Correctly calculate 10% of the full circumference, and mark the 10% segments from the front to the back of the head.
  • Accurately place a tape measure on the frontal polar electrode site to the occipital electrode site, measure the full distance, and calculate and mark the 20% increments
  • Accurately place a tape measure from one anterior temporal electrode site to the other, measure the full distance, and calculate and mark the 20% increments
  • Accurately place a tape measure from one posterior temporal electrode site, to the other, measure the full distance and calculate and mark the 20% increments
  • Explain various techniques to prevent hair from getting in the way of accurate measurements and ensure good visibility of marks.

Lesson 3 Modification to the 10-20 System

  • Describe the measurement technique for T1 and T2 electrodes
  • Explain new nomenclature for specific 10/20 system electrodes, including T7, T8 and P7, P8
  • Identify the electrode names for the expanded 10/10 system
  • Explain how to modify electrode locations to accommodate skull defects, swelling, wounds and I.Vs.
  • Describe special montages to incorporate the double interelectrode distance mandated for the recording of Electrocerebral Silence EEG recordings.

Lesson 4 Double Checking Your Marks

  • Use an interelectrode distance chart to document the distance between each electrode placed on a mannequin or human head, according to the 10/20 system
  • Calculate the difference between homologous electrodes using the completed chart, to determine the accuracy of electrode placement
  • Explain commonly made errors in head measurement, that can cause inaccurate lead placement

Lesson 5 Patient Preparation

  • Explain important patient preparation education instructions to ensure that the head is properly cleaned and prepared for lead placement
  • List the products used for electrode placement, and the proper use of each product
  • Explain the importance of balanced, low impedances when applying electrodes
  • Identify signs of unbalanced electrode impedences and electrodes that are not securely attached.
  • Describe techniques to ensure that electrodes remain secure as the patient moves during the recording

Lesson 6 The Pony Tail Method

  • Explain the advantages of using the pony tail method to prepare the head for electrode application
  • Explain how to divide up the hair, in segments, and secure with elastics to increase visibility and accessibility of key areas of the scalp
  • Describe the technique of placing electrodes and positioning the electrode wires to maximize electrode security
  • Describe the use of gauze to wrap the head to prevent electrodes from becoming loose

Lesson 7 Application Types

  • List the various electrode application techniques and the advantages and disadvantages of each method of placement
  • Describe paste application technique, using paste covered with gauze squares
  • Describe collodion application technique, using an air compressor to dry the collodion-saturated gauze
  • List concerns and risk factors to be considered when applying electrodes to ensure patient safety
  • List the chemical compound that makes up collodion, and the standard safety recommendations when handling collodion

Lesson 8 Types of Electrodes

  • Describe a variety of common electrode types
  • Explain how to select electrodes to ensure an artifact-free recording
  • Explain the concept of common mode rejection and the relationship between electrodes, CMMR and an artifact-free recording

Lesson 9 Pediatric Measurements

  • Describe specific measures to make a child more comfortable in the EEG lab, in preparation for head measurement and lead placement
  • Explain lead placement techniques to ensure good lead placement without injury to the child
  • List the pros and cons of using sedation for lead placement for the pediatric patient, and alternatives to sedation that can be employed
  • Describe techniques for lead placement in the neonate and premature infant

Lesson 10 Pitfalls and Common Errors

  • List ten common errors in technique that cause problems with accurate lead placement
  • Describe proper hand placement to secure tape measure and prevent slippage
  • Explain methods to check for errors and remedy inaccurate placements

Lesson 11 Sam as a Practice and Learning Aid and for the ABRET Exam Oral Exam Until 2013

  • Explain the utilization of mannequin heads for the ABRET Part II EEG Registry Exam
  • Describe the advantages of using a “Sam” head to practice measuring and applying electrodes in preparation for the ABRET exam.

Course grades:

  • Quiz: The International 10-20 System of Electrode Placement - 5%
  • Quiz: Step by Step Measurement - 5%
  • Quiz: Modifications to the 10-20 System - 5%
  • Quiz: Double Checking Your 10-20 Marks - 5%
  • Quiz: Patient Preparation in EEG - 5%
  • Quiz: The Pony Tail Method - 5%
  • Quiz: Electrode Application Types - 5%
  • Quiz: Types of Electrodes - 5%
  • Quiz: Pediatric Measurement and Application - 5%
  • Quiz: Pitfalls and Common Errors - 5%
  • Practice Exam Review - no credit
  • Final Exam 50%