MS-120BK ELECTRIC STIMULATOR (EXTENSION UNIT)

K110410 · Nihon Kohden Corp. · GYC · Aug 4, 2011 · Neurology

Device Facts

• Record ID: K110410
• Device Name: MS-120BK ELECTRIC STIMULATOR (EXTENSION UNIT)
• Applicant: Nihon Kohden Corp.
• Product Code: GYC · Neurology
• Decision Date: Aug 4, 2011
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 882.1310
• Device Class: Class 2
• Attributes: Therapeutic

Intended Use

When the Low output is selected the MS-120BK is used as a nerve stimulator for surgical procedures and brain mapping during treatment of patients with seizure disorders. When High output is selected the MS-120BK is used for the intraoperative diagnosis of acute dysfunction in corticospinal axonal conduction brought about by mechanical trauma (traction, shearing, laceration, or compression) or vascular insufficiency. The system is intended for use by qualified medical personnel within a hospital or clinical environment. The stimulator is available for use on any patients as determined by the qualified medical personnel.

Device Story

The Nihon Kohden MS-120BK is a dual-output constant current electric stimulator used as an extension unit for the MEE-1000A system. It functions as a nerve stimulator for surgical brain mapping or intraoperative diagnosis of corticospinal conduction dysfunction. The device receives control signals from the MEE-1000A via an amplifier (JB-116BK or JB-132BK). It delivers electrical stimulation pulses through a stimulation pod (JS-102B) or extension cord (BM-121B) to external electrodes. Operated by qualified medical personnel in clinical/hospital environments, the device allows selection of stimulation current, frequency, and pulse parameters. Output affects clinical decision-making by enabling real-time mapping and diagnostic monitoring during surgery, potentially benefiting patients by identifying functional brain areas or assessing nerve conduction integrity during trauma or vascular events.

Clinical Evidence

Bench testing only. No clinical data provided. Verification and validation testing performed in compliance with design control processes, including adherence to IEC 60601-1, IEC 60601-1-2, and IEC 60601-2-40 standards for medical electrical equipment and safety.

Technological Characteristics

Dual-output constant current stimulator; 350V max voltage; 200mA max current; 50 Ω output impedance. Supports monophasic, biphasic, and alternate pulse modes. Pulse duration 50-1000 μs; frequency 0.1-50Hz. Connectivity via MEE-1000A interface. Complies with IEC 60601-1, 60601-1-2, and 60601-2-40 standards.

Indications for Use

Indicated for surgical nerve stimulation and brain mapping in patients with seizure disorders (Low output) and intraoperative diagnosis of acute corticospinal axonal conduction dysfunction due to trauma or vascular insufficiency (High output). Use by qualified medical personnel in hospital/clinical settings on any patient population.

Regulatory Classification

Identification

A cortical electrode is an electrode which is temporarily placed on the surface of the brain for stimulating the brain or recording the brain's electrical activity.

Predicate Devices

• Nicolet Cortical Stimulator (K072964)
• Ojemann Cortical Stimulator (K924226)
• Digitimer D185 Multipulse Cortical Stimulator (K020400)
• Axon Eclipse Neurological workstation (K050798)
• Nihon Kohden SEN-4100 Electric Stimulator (K071969)

Submission Summary (Full Text)

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Nihon Kohden America, Inc. July 25, 2011

Traditional 510(k) Notification MS-120 Electric Stimulator

# K110410

### 510(k) Summary

ﺒﻪ .

| Company Name: | Nihon Kohden Corporation<br>90 Icon Street<br>Foothill Ranch, CA 92610 | AUG - 4 2011 |
|-----------------------------|------------------------------------------------------------------------------------------------------------------------------|--------------|
| Device Name: | Nihon Kohden MS-120BK Electric Stimulator (Extension Unit) | |
| 510(k) Sponsor,<br>Contact: | Nihon Kohden America, Inc.<br>90 Icon Street<br>Foothill Ranch, CA 92610 | |
| | Steve Geerdes<br>Director Quality Assurance and Regulatory Affairs<br>Phone: [phone] Ext. 3325<br>Fax: [phone] | |
| Summary Date: | 7/25/2011 | |
| Common Name: | MS-120BK Electric Stimulator (Extension Unit) | |

## Classification Names:

| Evoked Response Electrical Stimulator | 882.1870 | GWF |
|---------------------------------------|----------|-----------------|
| Cortical Electrode | 882.1310 | GYC<br>Class II |

## Predicate Device(s):

| Nicolet Cortical Stimulator | K072964 |
|-----------------------------------------------|---------|
| Ojemann Cortical Stimulator | K924226 |
| Digitimer D185 Multipulse Cortical Stimulator | K020400 |
| Axon Eclipse Neurological workstation | K050798 |
| Nihon Kohden SEN-4100 Electric Stimulator | K071969 |

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#### . 1.0 Description of Device

The Nihon Kohden MS-120BK is a dual (high & low) output constant current stimulator. The high and low setting, stimulation current and frequency of stimulation is selected by the user. The Nihon Kohden MS-120BK is connected to the MEE 1000A through the JB-116BK or JB-132BK amplifier.

In the Low output setting the Nihon Kohden MS-120BK applies cortical stimulation energy through the Nihon Kohden stimulation pod (JS-102B) which is connected to commercially available cortical electrodes (strip and grid electrodes).

In the High output setting, the MS-120BK outputs electrostimulation pulse through the Nihon Kohden extension cord (BM-121B) which is connected to commercially available stimulation electrode(s).

### 2.0 Intended Use of Device

When the Low output is selected the MS-120BK is used as a nerve stimulator for surgical procedures and brain mapping during treatment of patients with seizure disorders.

When High output is selected the MS-120BK is used for the intraoperative diagnosis of acute dysfunction in corticospinal axonal conduction brought about by mechanical trauma (traction, shearing, laceration, or compression) or vascular insufficiency.

The system is intended for use by qualified medical personnel within a hospital or clinical environment. The stimulator is available for use on any patients as determined by the qualified medical personnel.

#### 3.0 Technical Characteristics

The technical characteristics of the MS-120BK are equivalent to those of the predicate devices. The following tables summarizes equivalence.

| Stimulator Comparison | Predicate Device<br>Nihon Kohden<br>SEN-4100A (K#071969) | Digitimer D185 | New Device<br>Nihon Kohden<br>MS-120BK |
|------------------------|----------------------------------------------------------|------------------|----------------------------------------|
| Stimulator Output | | | |
| Voltage | 1000V | 1000V | 350V |
| Current | 1A (1k Ω load) | 1A (1k Ω load) | 200mA (1k Ω load) |
| Maximum Stimulation | | | |
| Energy | 50mJ | 50mJ | 40mJ |
| Output Impedance | less than 120 Ω | less than 120 Ω | 50 Ω |
| Stimulation Mode | Constant Voltage | Constant Voltage | Constant Current |
| Stimulation Parameters | | | |

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| Pulse Duration | 50 μs | 50 μs | 50-1000 μs |
|-----------------------------------------------|-----------------------------------------------------|-----------------------------------------------------|-------------------------------------------------------------|
| Output Frequency Range | 1 Hz | 1 Hz | 0.1-1Hz |
| Number of Pulse Trains | 1-9 | 1-9 | 1-9 |
| Interpulse Interval | 1.0-9.9ms | 1.0-9.9ms | 1.0-1000ms |
| Limitation of Voltage /<br>Current and Pulses | 1000V: 3 Pulses<br>510V: 6 Pulses<br>350V: 9 Pulses | 1000V: 3 Pulses<br>510V: 6 Pulses<br>350V: 9 Pulses | 200mA: 3 Pulses*1<br>142mA: 6 Pulses*1<br>115mA: 9 Pulses*1 |
| Polarity Change | OK | OK | OK |
| Monophasic | OK | OK | OK |
| Biphasic | NO | NO | OK |
| Alternate | NO | NO | OK |
| Maximum Charge | 50 micro-Coulomb | 50 micro-Coulomb | 200 micro-Coulomb |
| Pulse Shape | Rectangular | Rectangular | Rectangular |
| Maximum Energy Per Pulse | 50mJ | 50mJ | 40mJ |
| Maximum Energy Per<br>Second | 150mJ | 150mJ | 40mJ |
| Electrode Minimum Size | 0.5cm2 | 0.5cm2 | 0.5cm2 |
| Maximum Charge Density | 100 Micro-C/cm2 | 100 Micro-C/cm2 | 400 Micro-C/cm2 |
| Interface<br>Control From EP/EMG<br>Machine | MEE-1000A | NO | Only MEE-1000A |
| Trigger Input | OK | OK | OK*2 |
| Trigger Output | OK | OK | OK*2 |
| Foot Switch Control | OK | OK | OK*2 |

*1: The pulse width in the case

^{. *2:} Depends on interface of MEE-1000A

| Stimulator Comparison | Predicate Device Nicolet<br>Cortical Stimulator<br>(K#072964) | Ojemann<br>Cortical Stimulator<br>(K#924226) | New Device<br>Nihon Kohden<br>MS-120BK |
|------------------------------------------|---------------------------------------------------------------|----------------------------------------------|----------------------------------------|
| Constant Current Stimulator | Yes | Yes | Yes |
| Maximum Stimulation Charge | 15 micro-Coulomb | 20 micro-Coulomb | 4.5 micro-Coulomb |
| Current Stimulation Range | 0.1 to 15mA (peak) | 0 to 10mA (peak) | 0 to 15mA (peak) |
| Stimulation Frequency | 1 to 100Hz | 5, 10, 20, 50, 75,<br>100Hz | 0.1 to 50Hz |
| Stimulation Pulse Width Duration | 0.1 to 1.0 msec Per<br>Phase | 0.1 to 2.0 msec Per<br>Phase | 0.05 to 0.3 msec Per<br>Phase |
| Pulse Shape | Rectangular | Rectangular | Rectangular |
| Electrode Minimum Size | 0.04cm2 | 0.5cm2 | 0.04cm2 |
| Maximum Charge Density | 375 micro-C/cm2 | 40 micro-C/cm2 | 113 micro-C/cm2 |
| Maximum RMS Current Density<br>Per Pulse | 119 mA RMS/cm2 | 8.9 mA RMS/cm2 | 46 mA RMS/cm2 |

of 1ms

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#### 4.0 Data Summary

Testing of the Nihon Kohden System with the MS-120BK was performed in compliance with the Nihon Kohden Corporation design control process. Testing included:

> Software and hardware verification and validation, and the device is in compliance with the following voluntary industrial standards:

Medical Electrical Equipment Par1: General requirements for safety IEC 60601-J 1988 IEC 60601-1, Amendment 1 Part 1: General Requirements for safety, Amendment 1, 1991 IEC 60601-1, Amendment 2 Part 1: General Requirements for safety, Amendment 2, 1995 IEC 60601-1-2-40 * Part 2-40: Particular Requirements for the safety of electromyographs and evoked response equipment, 1998 IEC 60601-1-1 200 edition: Part 1-1: General requirements for safety -Collateral standard Safety requirements for medical electrical systems, 2000 IEC 60601-1-2 2" edition: Medical electrical equipment- Part 1: General requirements for safety - 2. Collateral standard: Electromagnetic compatibility, 2001 EN 60601-1: 1990 Equivalent to IEC 60601-1: 1998* EN 60601-1 Amendment 1 Medical equipment general requirements for safety, 1993 EN 60601-1 Amendment 2 Medical equipment general requirements for safety, 1995 EN 60601-1-1: 2001 Equivalent to IEC 60601-1:2001 Electromagnetic compatibility requirement test EN 60601-1-2:2001 CAN/CSA-C22.2 No. 601.1-M90 Medical electrical equipment, Part 1: General requirements for safety. CAN/CSA-C22.2 No. 601.1S1-94 Supplement No. 1-94 to CAN/CSA-C22.2 No. 601-1-M90 Medical Equipment- Part 1:General requirements for safety. CAN/CSA-C22.2 No. 60601-1-1-02 Medical electrical equipment, Part 1-1: General requirements for safety- Collateral: Safety requirements for medical electrical systems, 2006 CAN/CSA-C22.2 No. 60601-2-40-01 Medical electrical equipment, Part 2-40: Particular requirements for safety of electromyographs and evoked response equipment (adopted 60601-2-40: 1998 CAN/CSA-C22.2 No. 601.1B-90 Amendment 2 to CAN/CSA-C22.2 No. 601.1-M90 Medical equipment Part 1: General requirements for safety: 2002

5.0 Conclusions

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Substantial equivalence of the Nihon Kohden MS-120BK was demonstrated by testing in compliance with the Design Control process. The intended use and technology of the Nihon Kohden MS-120BK is equivalent to the predicate devices. No new questions of safety or effectiveness are raised.

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Image /page/5/Picture/1 description: The image shows a logo for the U.S. Department of Health & Human Services. The logo features a stylized caduceus symbol, which is a staff with two snakes coiled around it. The words "DEPARTMENT OF HEALTH & H." are arranged in a semi-circle around the caduceus. The image is in black and white.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Room -WO66-G609 Silver Spring, MD 20993-0002

Mr. Steve Geerdes Director Regulatory Affairs and Quality Assurance Nihon Kohden America, Inc. 90 Icon St. Foothill Ranch. CA 92610

AUG - 4 2011

Re: K110410

Trade/Device Name: Nihon Kohden MS-120BK Electric Stimulator (Extension Unit) Regulation Number: 21 CFR 882.1310 Regulation Name: Cortical Electrode Regulatory Class: Class II Product Code: GYC and GWF Dated: June 27, 2011 Received: June 28, 2011

Dear Mr. Geerdes:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA), You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set

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forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to http://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm11.5809.htm for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number [phone] or [phone] or at its Internet address http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours,
Keoia Alexander

Malvina B. Eydelman, M.D. Director Division of Ophthalmic, Neurological, and Ear. Nose and Throat Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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## Indications for Use Form

510(k) Number (if known):

Device Name: _ _ MS-120BK Electric Stimulator (Extension Unit)

Indications for Use:

When the Low output is selected the MS-120BK is used as a nerve stimulator for surgical procedures and brain mapping during treatment of patients with seizure disorders.

When High output is selected the MS-120BK is used for the intraoperative diagnosis of acute dysfunction in corticospinal axonal conduction brought about by mechanical trauma (traction, shearing, laceration, or compression) or vascular insufficiency.

The system is intended for use by qualified medical personnel within a hospital or clinical environment. The stimulator is available for use on any patients as determined by the qualified medical personnel.

Prescription Use (Part 21 CFR 801 Subpart D)

AND/OR

Over-The-Counter Use (21 CFR 801 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Kristen Bowsher

(Division Sign-Off) Division of Ophthalmic, Neurological and Ear, Nose and Throat Devices

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510(k) Number_K 110410