How to prepare the patient for threshold cortical testing
Transcript
Before you start testing, instruct the patient to turn off all their electronic devices in order to minimize noise.
Now look in your patient's ear to ensure no excess cerumen is present.
Clean the patient's skin behind each ear on the mastoid, the low forehead, and on the true vertex, which is on the top of the patient's head.
It is recommended to use this electrode montage.
However, if this is not possible, you can prepare the patient's high forehead instead.
Place your reference electrodes on the patient's mastoids, the ground electrode on their low forehead, and the active electrode on the true vertex or the high forehead.
Now test the impedance.
Impedances below five kiloohms are acceptable.
It is important that there is no more than two kiloohms of imbalance in impedances between electrodes.
The patient instructions will vary depending on the type of cortical test being done.
When ready, insert transducers in the patient's ear and start testing.
