MAGSTIM RAPID2 Operating Manual page 11

Magstim Rapid
2
3576-23-09
3.4 MEP POD CONNECTION
NOTE. The Rapid
2
must be switched off before connecting or disconnecting the MEP
Pod.
The Motor Evoked Potential (MEP) Pod is an optional component which allows the user to capture
EMG signals and display them on the UI. 2 channels are available. The MEP Pod should be mounted as
close as possible to the subject but should be kept away from sources of interference, such as power
cables. It is recommended that all EMG cables are screened to minimise interference.
The l\1EP Pod is designed to be used with surface electrodes only.
The MEP Pod is designed to be fitted to the Magstim Rapid
2
UI only. Do not attempt to colll.lect it to a
computer, or any other equipment, with a similar connector. To do so could result in electric shock/
bums to the patient at the site of electrode attachment. The MEP Pod com1ector has a hole deliberately
blocked to prevent incmTect connection.
C0:11."NECTION
The MEP Pod is attached to the rear right hand side of the UI when viewed from the rear. Remove the
plastic cover to expose a 15 way D Type socket. Attach the MEP Pod cable, ensuring that the plug is
properly inserted. The plastic cover has a notch in its lower edge through which the cable must pass.
This cover, when replaced, provides strain relief for the connector. Do not operate the equipment
without replacing this cover, as damage to the connector and the internal electronics of the UI is likely.
USE
Attach the EMG cable to the MEP Pod and snap the free connectors onto surface type electrodes (for
example, Kendall ARBO Hl24). Suitable electrodes are available from many medical supply
companies, and no recommendation is made as to a particular type. Electrodes should be chosen which
are suitable fix the collection ofEMG data, have snap connectors, and which are compliant ,vith local
regulations. \\'hen connecting the electrodes, follow the colour code on the MEP Pod.
The EMG connection cable should be screened and should be suitable for use ·when in direct contact
with the skin. No latex should be present in the cable.
The electrodes should be positioned on the target muscle which is controlled by the neurons being
stimulated. For example, if the area of the motor cortex vv-hich controls the hand is to be stimulated, the
surface electrodes should be placed on abductor digiti minimi, about !cm apart. The ground electrode
should be placed on the wrist. Care should be exercised when placing surface electrndes. It is important
that a consistent approach is observed, as the amplitude of the EMG signal is dependent on the position
of the electrodes. Good practice in relation to skin cleaning should be observed.
CAUTION
For safety reasons, do not leave patient cables attached to the MEP Pod if they are not being used. If an
unused cable is left connected, and the patient is connected to the other channel, there is the possibility
that the unused cable may touch an earthed surface which could allow cmTent to flow through the
patient to ground.
Do not allow the coil or the coil cable to come into close proximity ,vith the MEP Pod patient cables.
During discharge, current may be induced in these cables.
The MAGSTIM Company LTD
8
November 2009