MAGSTIM 200 Operating Manual March 2005

Magstim 2002

TABLE OF CONTENTS Page Numbers Guarantee

1

Section 1:

Description 1.1 Introduction 1.2 Contraindications 1.3 Indications for Use

2 2 2 2

Section 2:

Warnings and Precautions

3

Section 3:

Front Panel Description

5

Section 4:

Rear Panel Description

10

Section 5:

Preparations for Use

12

Section 6:

System Status Codes

15

Section 7:

Using the Magstim 2002 7.1 Description of the Coil 7.2 Coil Positioning 7.3 Discharging the Magstim 7.4 Recording of Evoked Responses

17 17 17 19 19

Section 8:

Safety Features 8.1 Coil Temperature Protection 8.2 Coil Disconnection 8.3 Other Safety Measures

21 21 21 21

Section 9:

Maintenance and Servicing: 9.1 Voltage Selection and Fuse Rating 9.2 User Maintenance 9.3 Technical Maintenance 9.4 Cleaning and Disinfecting 9.5 Servicing 9.6 Device Lifetime 9.7 Disposal

22 22 23 23 23 24 25 25

Section 10:

Specifications: General Specifications 10.1 Power 10.2 Ambient Temperature Requirements 10.3 Capacitor Life Expectancy 10.4 Output 10.5 Rear Panel 10.6 General 10.7 Handling 10.8 Packing Instructions

26 26 27 27 27 27 28 28 29 29

Section 11:

EMC Emissions and Immunity

30

Magstim 2002

GUARANTEE

Equipment manufactured by the Magstim Company Limited is fully guaranteed covering materials and workmanship for a period of one year from the date of shipment. The capacitor is guaranteed for one year, or 200,000 discharges, which ever comes first. The Magstim Company Limited reserves the right to perform guarantee services in its factory, at an authorised repair station, or at the customer's installation. The Magstim Company's obligations under this guarantee are limited to repairs or, at the company's option, replacement of any defective parts of our equipment, except batteries, without charge if said defects occur during normal service. Claims for damages during shipment must be filed promptly with the transportation company. All correspondence concerning the equipment must specify both model name and/ or number and serial number, as it appears on the invoice for said equipment. Improper use, mishandling, tampering with, or operation of the equipment without following specific operating instructions will void this guarantee and release the Magstim Company from any further guarantee obligations. The Magstim Company will only accept responsibility for the effects on safety, reliability and performance of the equipment if: i modifications or repairs are carried out by persons authorised by The Magstim Company. ii the electrical installation of the relevant room complies with local regulations, and iii the equipment is used in accordance with the instructions for use.

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Magstim 2002

SECTION 1: DESCRIPTION

1.1 INTRODUCTION This manual is written for users of the Magstim 2002, an instrument used in the magnetic stimulation of neuromuscular tissue. The Magstim 2002 is a device capable of stimulating neuromuscular tissue by inducing small currents in the tissue using a brief pulse of electromagnetic energy. This method of stimulation enables deep, and otherwise inaccessible, nerves to be stimulated easily and relatively painlessly. In addition, no skin preparation is required and stimulation can be achieved through clothing. INDICATIONS FOR USE The Magstim 2002 is a magnetic nerve stimulator intended for the stimulation of neuromuscular tissue. The Magstim 200² system is for use by, or under the supervision of a medical practitioner only. CAUTION Federal law restricts this device to sale by or on the order of a practitioner licensed by the law of the State in which he/she practices to use or order the use of the device. CONTRAINDICATIONS Magstim 2002 and its accessories should not be used on or in the vicinity of patients or users with cardiac demand pacemakers, implanted defibrillators and/or implanted neurostimulators.

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Magstim 2002

SECTION 2:

USA Only

WARNINGS AND PRECAUTIONS

CAUTION: Magnetic Stimulators have not been cleared by the FDA for cortical stimulation. Investigational human uses require that the user complies with the FDA regulations regarding Investigational Devices. Please visit www.fda.gov/cdrh or www.magstim-us.com for more information. CAUTION: In the USA, Federal Law restricts this device to sale by or on the order of a practitioner licensed by the law of the State in which he/ she practices to use or order the use of the device. Attention: Consult accompanying documentation before using the Magstim 2002. CAUTION: The Magstim 2002 and its stimulating coils must not be used on, or in the vicinity of, patients or subjects with cardiac demand pacemakers, implanted defibrillators, or other electronic implants. The Magstim 2002, its coils and accessories generate high intensity magnetic pulses. The induced eddy current is of sufficient magnitude to stimulate nerves and muscle. The strong magnetic pulses generated by stimulating coils induce eddy currents in any conductive medium such as the human body, nearby metallic objects or electronic devices. NB Particular care must be taken to ensure that leads connected directly to the patient, or other equipment, are not in a position where the stimulating coil can couple resulting in currents being induced in them. Do not discharge the Magstim with the stimulating coil in the vicinity of metallic objects or these may be projected, moved and/or damaged. The Magstim 2002 must not be used in an explosive atmosphere or in the presence of flammable anaesthetics. When the magnetic pulse is delivered, a discharge click is produced by the Magstim 2002 and its stimulating coil. This discharge click may startle. Where possible avoid the use of the stimulating coil near the ears. The use of ear plugs is recommended. High voltages are present within this instrument. Do not remove covers. Refer servicing to qualified personnel.

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Magstim 2002

The Magstim 2002, its stimulating coil and accessories must not be used if there are any signs of external damage or if any parts are damp or wet. Cortical magnetic stimulation runs the risk of inducing seizures.

Do not discharge the Stimulating Coil in the vicinity of objects sensitive to magnetic fields. Examples are credit cards, floppy disks and computer screens. Trigger input/output – only equipment that meets EN 60601-1 ( IEC 601-1 ), and configured in compliance with EN 60601-1-1, should be connected to this input. Protection circuits in the Magstim Magnetic Stimulator disable the equipment if the surface temperature of the Coil exceeds to set limit. The 90mm Coil is intended for transient use, the surface temperature limits for which, being 50oC. If it is intended that the coil be used for more prolonged contact, the proposed protocol must be run, prior to its application on a patient, to ensure that the surface temperature does not rise above 41oC during operation. Coils must not be immersed in water, put in an ice bucket, or refrigerated. Not even if placed within a plastic bag. The coils do not have any specialised protection against the ingress of liquids, therefore conditions where ingress of liquid, or the forming of condensation within the coil, can occur must be avoided as the electrical insulation will be compromised. Cooling must only be performed by using a flow of cool air from a fan or air conditioning unit. Due to thermal lag, the surface temperature of the Stimulating Coil will continue to rise following the coil over-temp activating and forcing the main unit into a standby condition. Therefore, the Coil must be removed from the patient as soon as the replace coil symbol is illuminated. There are currently few medical papers available regarding the effects of magnetic stimulation on the unborn child/ foetus or the expectant mother. As a result of this, we are unable to verify the safety of the Coil's use on, or by, pregnant women. We recommend that anyone wishing to use the Coil on a pregnant woman, or use it whilst pregnant, should contact the Magstim Company Ltd. for more information as new medical papers become available. On no account must the Magstim 2002 and its accessories be used in environmental conditions outside those specified in this operating manual.

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Magstim 2002

SECTION 3:

NOTE

FRONT PANEL DESCRIPTION

1. All operating functions described in this section assume that the mains power switch, located on the rear panel, is in the ON position. 2. For the Magstim 2002 - 3006-00, which is supplied without the control unit shown in the above diagram, functions 4 to 17 are implemented on the remote control coils. For details of the remote control coils see Magstim Remote Control Coils Operating Manual – 3179-23.

ON/OFF (Standby) Button (1) This switch toggles the operational state of the Magstim 2002. On initial application of mains power, the Magstim 2002 enters its Standby state. This is indicated by the Power State indicator (3) flashing. Pushing the ON/OFF switch when the unit is in its Standby state will set the Magstim 2002 into its operational state. This is indicated by the Power State indicator (3) being continuously illuminated. All LEDs and symbols will illuminate within a period of 5 seconds. At the end of 5 seconds the OUTPUT % DISPLAY will default to 30%, and the inactive default condition indicator (10) will illuminate. At the end of the session the Magstim 2002 can be returned to its Standby condition by pushing the ON/OFF switch.

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Magstim 2002

ARMED Indicator (2) This LED is illuminated when the unit is in an armed condition. This indicates that there is high voltage present inside the unit. On power-up the armed indicator on the main unit flashes three times as part of a selftest programme.

Unit Power Status Indicator (3) Condition 1. – While the Magstim 2002 is in the Standby state, as controlled by the Mains Power switch (1), this LED flashes at approximately 0.5Hz, indicating that the unit is in a standby condition. Condition 2. – While the Magstim 2002 is in the Operational state, as controlled by ON/ OFF (Standby) button (2), this LED is continuously lit, indicating that the unit is in the Operational state.

OUTPUT % DISPLAY Indicator (4) This display is used to show the following: 1. The set power output as a percentage of maximum. After turning the unit on using the ON/OFF button (1) the OUTPUT % DISPLAY will display 30%. The OUTPUT CONTROL knob (16) can then be used to change the output level in 1% steps. Note: The OUTPUT % DISPLAY only shows the level the Magstim 2002 is actually charged to if the READY symbol (12) is illuminated. 2. The system status codes. These are detailed in Section 6 – System Status Codes.

COIL IN Indicator (5) This green LED will illuminate if there is a coil detected as being connected correctly to the Magstim 2002.

COIL TEMPERATURE Indicators (6, 7 & 8) These LED’s represent the surface temperature of the coil. The LED’s illuminate sequentially as the coil temperature rises, beginning with the bottom green LED and ending with the amber LED. When the amber LED is lit, it means that the coil is getting close to its maximum operating temperature. As soon as it reaches its maximum operating temperature, the replace coil indicator will illuminate and the M2002 will put itself into a safe default mode and discharge internally. NB If the temperature of the coil is below 5oC, the system will not operate. The Magstim 2002 will remain in its inactive default condition until it detects that the coil temperature has risen above 5oC.

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Magstim 2002

REPLACE COIL Indicator (9) This red LED will illuminate if any of the following conditions are present: 1. The Coil connected is not compatible with the Magstim 2002. 2. The surface temperature of the connected Coil has risen above its set limit. 3. The connected Coil is faulty. 4. There is no Coil connected. If this LED is illuminated the Magstim 2002 will be put into its safe inactive default condition.

DEFAULT CONDITION Indicator (10) This LED is illuminated when the Magstim 2002 has been put into its safe inactive default condition.

ARMED Indicator (11) This LED is illuminated when the unit is in an armed condition. This indicates that there is high voltage present inside the unit.

READY Indicator (12) This LED is illuminated when the Magstim 2002 is charged and ready to be triggered. A magnetic pulse can be produced by depressing one of the Trigger Enable switches at the base of the stimulating coil and depressing the TRIGGER button (15), or by depressing the footswitch, or by applying a Trigger Input to the TRIGGER INPUT connector on the rear panel. Note: If the instrument has not been triggered for over 1 minute after the READY symbol is illuminated the unit will automatically select the default mode and discharge internally. The function represented by this symbol is not implemented on the Magstim 2002.

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Magstim 2002

RUN Button (14) The Magstim 2002 can be put into the ARMED mode by momentarily pushing the RUN button. This can only be achieved if the stimulating coil is connected to the COIL OUTPUT socket (18) and the REPLACE COIL symbol (9) is not illuminated. In the ARMED mode the ARMED symbol (11) will illuminate and the instrument will charge to the level displayed on the OUTPUT % DISPLAY (4).

TRIGGER Button (15) The Magstim 2002 can be triggered, and a magnetic pulse produced, by pushing the TRIGGER button when the READY symbol (12) is illuminated and one of the safety buttons at the base of the stimulating coil is activated. The instrument will continuously charge and discharge if the TRIGGER button is pressed and held.

OUTPUT CONTROL (16) The output level setting as shown on the OUTPUT % DISPLAY (4) can be increased, or decreased, by rotating the control clockwise or anticlockwise respectively. Each complete 360º rotation changes the output level by approximately 20%.

SYSTEM STOP Button (17) The Magstim 2002 can be put into the safe inactive default mode by momentarily pushing the STOP button. In this mode the DEFAULT CONDITION indicator (10) will illuminate and the instrument will discharge internally. Note: The default mode is automatically selected if the coil is disconnected, becomes faulty, the surface temperature of the connected Coil has risen above its set limit, the SYSTEM STOP button is activated, the instrument detects an internal fault, or if the READY symbol has been illuminated for over 1 minute without the instrument having been triggered.

COIL OUTPUT SOCKET (18) This socket is used to connect the stimulating coil to the Magstim 2002. Note that the unit cannot be armed and triggered unless the stimulating coil is connected to this output. Ensure that the locating spot on the coil plug is correctly lined up with the coil output socket before inserting the plug. When the coil plug is fully engaged in the socket, lock the plug in place by turning the black locking ring clockwise.

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Magstim 2002

HIGH VOLTAGE Symbol This sign warns that voltages in excess of 1500V are present within the instrument (see also Section 2).

ATTENTION Symbol See warnings in Section 2 regarding the use of the Magstim 2002.

APPLIED PART Symbol BF Type Applied Part. The applied part of this device, namely the stimulating coil, is electrically isolated from the other parts of the equipment as required by safety standards of BSEN60601-1.

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Magstim 2002

SECTION 4:

REAR PANEL DESCRIPTION

MAINS POWER Switch (1) To connect the mains supply to the Magstim 2002 set the mains power switch the ON (I) position. To disconnect the mains supply, the mains switch on the rear panel of the unit must be set to the OFF (0) position.

ISOLATED INTERFACE (RS232/ trigger) Port (2) WARNING

(Only equipment complying with EN 60601-1, and configured in compliance with EN 60601-1-1, should be connected to this interface port) (Unless otherwise indicated, signal levels are 5V CMOS Logic)

Pin Connections (26D)

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1. Aux GND 10. Aux. +5V 19. Aux GND 2. * 11. Aux. GND 20. * 3. Tout – O/C 12. Rx (RS232 Level) 21. * 4.* 13. Tx (RS232 Level) 22. * 5. +ve Trigger In 14. * 23. * 6. -ve Trigger In 15. * 24. †Trigger Edge/ Level 7. +ve Trigger Out 16. * 25. * 8. -ve Trigger Out 17. * 26. * 9. * 18. * * Factory Use Only – DO NOT CONNECT † No Connection – Edge Trigger Connect Pin 24 to Pin 19 – LEVEL Trigger

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TRIGGER INPUT/ OUTPUT The trigger input is used to synchronise the Magstim 2002 to an external trigger input. Application of a 5V CMOS Logic Level to this input will result in the instrument being triggered, provided the READY symbol (12) is illuminated and one of the safety buttons at the base of the stimulating coil is activated. This signal must be active for at least 10µs. In most instances the Magstim 2002 will be used in conjunction with a recording instrument supplied by various manufacturers. In these cases the Magstim and the recording instrument will have to be synchronised so that the magnetic pulse produced by the Magstim occurs exactly at the start of the recording sweep of the recording instrument. Almost all recording instruments have some means of accepting an external trigger signal via either a dedicated input port or via the foot switch trigger input. The trigger output supplies a synchronisation signal to the external recording instrument. A 100µs 5V CMOS Logic Level pulse of either polarity is provided at this output whenever the Magstim is discharged. Attention: Consult accompanying documentation before using the Magstim 2002.

FOOT SWITCH Pneumatic Socket (3) This socket is used to connect the supplied pneumatic FOOT SWITCH to the Magstim 2002. The FOOT SWITCH can be used to trigger the instrument when one of the safety switches at the base of the stimulating coil is activated and the READY symbol on the front panel is illuminated.

COOLING FAN OUTLET (4) With the Magstim 2002 turned on, air is drawn through slots at the bottom of the instrument and expelled through the FAN OUTLET. Since it is important to allow unrestricted air flow, the instrument must be placed on a hard surface. In addition, there should be no obstructions placed closer than 50mm to the FAN OUTLET.

POWER ENTRY MODULE (5) FUSE ACCESS & VOLTAGE SELECTOR (6) See Section 9 of this operating manual for instructions on how to replace the fuses. NB The fuses should only be replaced with those specified in this operating manual.

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Magstim 2002

SECTION 5: PREPARATIONS FOR USE IMPORTANT To avoid interference problems the Magstim 2002, and its accessories, should not be used in the vicinity of any equipment that does not comply with EMC Standard EN 60601-1-2. Before using the instrument, ensure that the correct fuses are fitted and that the voltage selector is set to suit the supply voltage (see Section 9). Check the Magstim 2002 and its accessories for any signs of damage. If the Magstim 2002, or any of its accessories, are damaged in any way they must not be used. If a number of Magstim 2002 units are being used, or the Magstim 2002 is part of a BiStim system, it may be desirable for the units to be stacked on top of each other. The Magstim 2002 enclosure has been designed such that the units may be safely stacked on top of each other. The maximum number of units that can be safely stacked on top of the base Magstim 2002 is 3. Attempts to exceed this limit could result in crush damage to the base Magstim 2002. In addition, the stacked units could become unstable and overbalance, causing injury to the patient, or user, and damage to the Magstim units. 1. Insert the pneumatic connector of the foot switch to the rear panel FOOTSWITCH socket on the Magstim 2002. 2. If a recording device is being used, synchronise the Magstim with the recording instrument by following the instructions in Section 4 – ISOLATED TRIGGER I/O Port. 3. Ensure that the locating spot on the coil plug is correctly lined up with the COIL OUTPUT SOCKET, located on the front panel of the Magstim 2002. Insert the connector of the stimulating coil into the output socket. When the coil plug is fully engaged in the socket, lock the plug in place by turning the black locking ring clockwise until it clicks into place.

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Magstim 2002

COIL Please note: it is important that the coil is connected correctly. If the coil appears to be misaligned, remove and re-connect the coil. Do not use if the coil appears misaligned.

4. Set the MAINS POWER switch on the rear of the unit to the ON (I) position. The Unit Power Status Indicator LED will flash at approximately 0.5Hz, indicating that the unit is in a standby condition. 5. Push the ON/OFF button on the front panel of the unit. The Unit Power Status Indicator LED will be continuously lit, indicating that the unit is operational and is in its safe inactive default condition. 6. All LEDs and symbols will illuminate within a period of 5 seconds. At the end of the 5 second period, the OUTPUT % DISPLAY will indicate an output power level of 30%, and the DEFAULT CONDITION indicator will remain illuminated. 7. Ensure that all indicator LEDs are functioning properly before proceeding; if not, contact The Magstim Company Service Department.

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Magstim 2002

8. Press the RUN button. The ARMED indicator will illuminate and when the instrument is charged to 30% the READY indicator will also illuminate. This indicates that the instrument is ready for use. Note: If the instrument has not been triggered for over 1 minute after the READY symbol is illuminated the unit will automatically select the default mode and discharge internally. 9. Hold the stimulating coil and press one of the Trigger Enable switches located on either side of the coil handle. Press and hold the TRIGGER key on the front panel, or depress and hold the footswitch. There should be a clicking noise emanating from both the stimulating coil and the Magstim, each time the Magstim is discharged, indicating that a magnetic pulse is being produced. Note: When using a standard 2nd Generation Coil, pressing one, or both, of the safety switches at the base of the stimulating coil will enable the armed M2002, allowing it to be triggered either via the trigger button on the unit – item 15 in Section 3 (front panel description) of this operating manual, or the footswitch – item 3 in Section 4 (rear panel description) of this operating manual. If a Remote Control Coil is being used, depression of one of the safety switches will cause the system to arm, depression of the second switch will trigger the system. On no account must the trigger enable buttons on the stimulating coil be permanently activated, by taping down, or any other method of fixing. They are designed as a safety interlock, to disable them could result in a serious injury as a result of an inadvertent discharge of the coil. Ensure the instrument is functioning properly before proceeding. Note: The Magstim 2002 can also be triggered by applying a signal to the TRIGGER INPUT Port, located on the rear panel of the unit. Completion of Session: During prolonged use, the temperature of some of the internal components of the Magstim 2002 will tend to rise. During operation this is regulated by the operation of the cooling fan. However, when the unit is switched off, the cooling operation is terminated. Therefore, it is recommended that, if the Magstim 2002 has been subject to prolonged use, the unit is left switched on for approximately ten minutes after the last session has been completed, to allow the fan to cool the unit.

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Magstim 2002

SECTION 6:

SYSTEM STATUS CODES

BASE Controller Error Codes produced by the User Interface. Error Codes U24 U25 U26 U27 U28 U29 U30 U31 U32 U33 U34 U35 U36

Description POWERDOWN Stack underflow Stack overflow RTS overrun Watchdog Timeout ROM Checksum Incorrect Unexpected RESET Unknown serial interrupt CSIO overrun Debug error No serial communications Loss of communication Bad NVRAM Checksum

Error codes produced by Coil. Error Codes C01 C02 C03 C04 C05 C06 C07 C08 C09 C10 C21 C22 C23 C24 C25 C26 C27 C28 C29 C30

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Description ROM Checksum Incorrect. EEPROM Checksum Incorrect. Invalid coil Category. Invalid Power Identification . Temperature sensor circuit failure. Bad Serial command or received data checksum. Internal Software Error. Invalid Coil Temperature ID. Invalid temperature algorithm coefficient. Coil controller malfunction. Coil Disconnected/ Coil Under Temperature. Brown Out Detected. No serial Communications. Bad Serial command of received data checksum (outside TRIGGATE). EMC Detected (Coil adapter only). Invalid Coil Power Identification (Coil adapter only). Hardware Stop activated. Watchdog Timeout. Temperature Interlock 3 activation. Coil stop line fault.

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Error codes produced by base system. Error Codes E61 E62 E63 E64 E65 E66 E67 E68 E70 E71 E72 E73 E74 E75 E76 E77 E78 E79 E80 E81 E82 E83 E84 E85 E86 E87 E88 E89 E90

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Description Power fail Stack underflow Stack overflow RTS overrun WD Timeout Unexpected reset Bad checksum SYS debug error Coil under temperature Coil max difference Stack over temperature Stack under temperature Stack max difference HVCAP over temperature HV Transformer over temperature Charge threshold failure VREF check failure HVCAP voltage comparison failure Charging fault HV over voltage Invalid system configuration Stop line fault Base coil stop line fault UI stop line fault Dump system fault WARNING – high voltage may be present up to 20 minutes after use on internal high voltage capacitor. Invalid coil category for current system configuration. Invalid NVRAM Checksum. Faulty charging relay detected Base arm LED drive failure

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SECTION 7: USING THE MAGSTIM 2002 7.1 DESCRIPTION OF THE COIL – Standard 90mm Coil – 3193-00 Magnetic nerve stimulation can be achieved by discharging the Magstim 2002 with the Stimulating Coil in the vicinity of neuromuscular tissue. Current flows from the instrument through the coil in only one direction. However, depending upon which side of the coil (labelled A or B) is facing up, the direction of the current flow relative to the stimulated tissue will change. Standard 90mm Stimulating Coil - 3193-00

With Side A visible and Side B facing the area to be stimulated, coil current flows in the anti-clockwise direction and the induced tissue current flows in the clockwise direction during the stimulating phase. With Side B visible and Side A facing the area to be stimulated, coil current will flow in the clockwise direction and induced tissue current flows in the anti-clockwise direction. The convention used above is that, in the coil, current flows from positive to negative. In the tissue current flow refers to ionic (+) movement.

7.2 COIL POSITIONING Correct coil positioning is essential to allow accurate measurements of the important parameters such as conduction latency, threshold of stimulation, response size and waveform morphology. The MAGSTIM 2002 is supplied as standard with the Standard 90mm Coil (P/N 3193-00), which is designed for the purposes of deep nerve stimulation stimulation. Stimulating the motor cortex using the Standard 90mm Coil produces responses which can be recorded from the majority The Magstim Company Limited

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Magstim 2002

of muscles in the body allowing for the functional assessment of motor pathways. In the case of the MAGSTIM the discharge current in the stimulating coil and the resulting magnetic pulse is mono-phasic allowing for mono-hemispheric stimulation. To record the best responses from muscles in the right side of the body always place the coil such that Side A is visible to the operator and Side B is touching the subject. To record the best response from the left side of the body always place the coil such that Side B is visible to the operator. The above rules should be observed when stimulating the motor cortex or the spinal nerve roots. The induced stimulating current flows clockwise under the coil winding when viewing Side A and counter-clockwise when viewing Side B. Since the motor cortex is more sensitive to current flowing from posterior to anterior, clockwise induced current primarily stimulates the left motor cortex and counter-clockwise induced current stimulates the right motor cortex. When recording from muscles in the arms and hands position the Standard 90mm Coil centrally on the vertex. In the case of circular coils

Stimulation takes place under the winding and not under the coil centre. When recording from muscles in the lower limbs move the Standard 90mm Coil forward from the vertex and contra lateral to the target muscle by approximately 5cms (2 inches) each way such that part of the coil winding lies over the central fissure.

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