Stack 1 Electrodes & Application
What is the recommended depth of sphenoidal electrodes?
3-4 cm Deep for flexible wire electrodes Insert bilaterally through the skin below the zygomatic arches in the direction of the foramen ovale by an electroencephalographer or qualified physician
Grids are placed epi- or subdurally over the cerebral cortex and require a craniotomy. Electrode "strips" consist of a row of disks embedded in silicone rubber, or a bundle of fine wires, each tip of which is a recording point. Strips are usally inserted through a burr hole.
Describe the differences in placement of intracranial grids and electrode strips.
Use of nonferrous metals such as platinum and nichrome allows MRI verification of electrode location
Name a MRI compatible material
Inferior surface of the frontal lobes
Nasoethmoidal electrodes record from which area (s)?
False. Sphenoidal electrodes must be placed by a qualified physician
True or False: Sphenoidal electrodes may be placed by qualified, credentialed technologists
The 10% or 10-10 System of Electrode Application
What type of EEG lead application system is often used for research and uses over 2x times the number of leads? (see figure)
What is the acceptable application / securing lead placement technique (i.e. wrapping head) for disk electrodes per ACNS guideline for LTM?
collodion. Paste alone is not recommended
Sphenoidal electrodes record activity from where?
mesial and anterior temporal lobe is measured by what type of electrode?
What are Inctracranial Electrode discs made from?
platinum or stainless steel is the best material for what type of electrode?
Mesial temporal structures without requiring penetration of the skull. A 1-4 contact flexible electrode is placed in the ambient cistern with the aid of a needle inserted through the foramen ovale.
Foramen ovale electrodes record from which structures(s)?
Platinum or stainless steel
Intracranial electrodes are made from what material(s)?
Foramen ovale, mesial / anterior temporal lobe
Sphenoidal electrodes target which area(s)?
Needle electrodes, nasopharyngeal
Which types of electrodes are not recommended for long term recording?
2. T9
With respect to the 10-10 system of electrode placement (see figure), which electrode site is lateral to T7? 1. C5 2. T9 3. FT7 4. TP7
3. T10
With respect to the 10-10 system of electrode placement (see figure), which electrode site is lateral to T8? 1. TP8 2. P8 3. T10 4. C6
1. C6
With respect to the 10-10 system of electrode placement (see figure), which electrode site is medial to T8? 1. C6 2. T10 3. FT10 4. TP8