The AS40 amplifier system is designed for use in the recording of routine EEG, overnight sleep/EEG (PSG, Polysomnography), and other neurophysiological monitoring applications (EMG and Evoked Potentials). This device is intended to be used only by physicians, technicians, or other medical professionals that are trained in either electroencephalography or polysomnography.
Device Story
AS40 is a 40-channel AC amplifier for EEG and polysomnography; provides signal conditioning (amplification, filtering, safety isolation) and digitization of physiological signals. Inputs include electrodes for EEG/EMG/Evoked Potentials and auxiliary DC inputs (e.g., oximeter, CPAP, capnometer). Device connects to a host computer via 10BaseT Ethernet (TCP/IP). Host computer software controls sampling rates, data transmission, and storage. Used in clinical settings (e.g., bedside) by trained professionals. Features include integrated pulse oximeter support, electrode impedance testing with LCD status display, and photic stimulation control. Benefits include standardized signal acquisition and centralized digital monitoring/storage for neurophysiological assessment.
Clinical Evidence
Bench testing only. No clinical data provided. Testing verified functional operation, performance specifications, and compliance with safety/EMI/EMC standards (IEC601-1, IEC601-1-2, IEC601-2-26, UL2601-1, CSA22.2No.601-1).
Technological Characteristics
40-channel AC amplifier (expandable to 50); 8 DC auxiliary channels. 16-bit A/D resolution; simultaneous sampling up to 800 Hz. CMRR >80dB; input impedance 10 MOhms. Connectivity: 10BaseT Ethernet. Power: +12V DC medical-grade supply. Patient isolation: optical/transformer/capacitor. Form factor: 7" x 6" x 2" plastic housing. Integrated LCD for impedance testing and configuration. Standards: IEC601-1, IEC601-1-2, IEC601-2-26, UL2601-1, CSA 22.2 No. 601.1.
Indications for Use
Indicated for patients requiring routine EEG, overnight sleep/EEG (PSG), EMG, or evoked potential monitoring. Intended for use by trained physicians, technicians, or medical professionals.
Regulatory Classification
Identification
An electroencephalograph is a device used to measure and record the electrical activity of the patient's brain obtained by placing two or more electrodes on the head.
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AUG 2 9 2002
K 021807
#### EXHIBIT A
#### Grass-Telefactor Product Group
Astro-Med, Inc. West Warwick, RJ 02893 USA Tel: (401) 828-4000 Fax: (401) 822-2430 Contact Person: Peter L Fuller May 31, 2002
# 510(k) Summary of Safety and Effectiveness
# Grass-Telefactor AS40 Amplifier System
# 1, Submitter Information
| Submitter's Name: | Peter L Fuller<br>Assistant Chief Engineer |
|-------------------|----------------------------------------------------------------------------------------------|
| Company: | Grass-Telefactor Product Group, Astro-Med, Inc.<br>570 Liberty Street<br>Braintree, MA 02185 |
| Telephone: | (781) 848-2970 |
| Facsimile: | (781) 848-2974 |
### 2. Identification of the Device
Name of Device: Grass-Telefactor AS40 Amplifier System OLV. Classification: Electroencephalograph, GWQ, Class II, per 882.1400
#### 3. Equivalent Devices
This product is similar in design, function, and intended use to the Bio-logic SleepScan NETLINK, 510(k) No: K003681 and the Compumedics E-SERIES EEG System, 510(k) No: K000068.
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Like these equivalent products, the Grass-Telefactor AS40 is designed to provide the signal conditioning interface (physiological signal amplification, filtering, safety isolation, and digitization) between the patient and a computer platform. When connected by an Ethernet cable or network to a computer with the appropriate software these equivalent systems are designed to monitor physiological signals such as EEG and store the signals to the computer's hard drive. These products have the same intended use and essential performance and safety characteristics.
#### 4. Description of the Device
The AS40 is a compact 40-channel AC amplifier unit designed for electroencephalography and polysomnography recording applications. The AS40 provides for patient safety isolation, signal conditioning (physiological signal amplification and filtering), and digitization. Communications with a single host computer are accomplished using TCP/IP protocol over a 10BaseT Ethernet network or dedicated cable. A host computer, using the appropriate software, sets the sample rate, starts and stops the data transmission, monitors the digital data, and stores it to hard disk.
The AS40 is enclosed in a plastic housing approximately 7" x 6" x 2" (17.78 x 15.24 x 5.08 cm) in size and it can be attached to a cart arm, mounted on a wall next to a patient bed, or sit flat on a tabletop. It can be configured for up to 40 AC and 8 DC channels. An integrated pulse oximeter connection is built into the unit that supports an optional tethered OEM pulse oximeter manufactured by Nonin. The patient connection module or electrode input box is referred to as a personality module in the AS40 system. The personality module connection is located on the top surface of the unit (two 32-pin connectors). The housing for this is a small plastic enclosure that can bave up to 40 AC channels with 'SafeLead' (protected) electrode connections, along with a reference and ground 'SafeLead' electrode connection. A customized overlay can be made for customer specific labeling schemes. The personality module can be attached either directly to the AS40 or tethered for easier positioning next to a patient bed. An LCD display with menu controls is located on the top surface of the unit along with the personality module connection. Menu selections can be made for configuring the unit, communicating with the host computer, and implementing the electrode impedance test. The LCD also displays status information such as electrode impedance test values.
Power is supplied to the AS40 through a rear side connector that attaches to a medical-grade regulated power supply (+12 volts DC). A 36-pin connector is also located on the rear side and it allows for the connection of a small plastic tethered auxiliary DC input box (DCM8) with 8 available connections for 3.5 mm jacks. Auxiliary DC inputs can come from devices such as an oximeter, a CPAP unit, or a capnometer. Also available through this 36-pin connector is a patient/event push
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button. All other connections (Ethernet, oximeter, photic stimulation control, etc.) are also located on the rear side of the AS40.
#### 5. Indications for Use
The AS40 amplifier system is designed for use in the recording of routine EEG, overnight sleep/EEG (PSG, Polysomnography), and other neurophysiological monitoring applications (EMG and Evoked Potentials). This device is intended to be used only by physicians, technicians, or other medical professionals that are trained in either electroencephalography or polysomnography.
#### 6. Comparison of Technological Characteristics
The design and technological features of the AS40 and the predicate devices are similar. All of the systems provide connections to the patient via a standardized plugin interface for commonly used EEG electrodes and are intended to record from the same anatomical sites. All of the systems perform amplification and filtering of the bio-potential signals acquired from these electrodes. Each system has an integrated (built-in) oximeter. Each has a means for digitizing the channels and transmitting the sampled EEG and physiological data to a computer over an Ethernet cable or network. Each system has a calibration mode, the means of testing electrode impedances, and means of controlling a flash unit. The performance specifications are also similar for each system, which are well agreed upon by the EEG community (amplifier filter settings, gain, and resolution).
The essential safety characteristics of the devices are identical. Each is powered from a low-voltage DC power supply via a medical-grade power supply as the primary AC safety isolation. Each relies additionally on a second level of safety isolation using either optical, capacitor, or transformer isolation means to isolate the patient leads from ground. Finally, each device is designed to operate with recording and review software separately approved and provided by or recommended by the device manufacturer.
The major difference between these devices is only in the physical packaging, input connection capabilities, and total channel count. The Bio-Logic device is slightly larger with the patient connection box contained in the main unit with an optional tethered version available and it has support for 40 channels. The Compumedics device is smaller than both the Grass-Telecfactor AS40 and the Biologic device but consists of two modules one being the main unit and the other the patient connection box and it has support for up to 57 channels. The Grass-Telefactor AS40 can be a one-piece unit with the patient connection box directly connected to the base unit or separated with the patient connection box tethered and it has support for up to 50 channels.
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The following table is provided to demonstrate the AS40's technical characteristics present no significant differences when compared to those of the predicate devices.
## Comparison Table
| Technical<br>Characteristic | Grass-Telefactor<br>AS-40 | Bio-logic<br>SleepScan NetLink | Compumedics<br>E-series EEG |
|---------------------------------------------------------|------------------------------------------------------------------------------|-------------------------------------------------------------------|------------------------------------------------------------------------|
| Device Class,<br>Category | II<br>Electroencephalogra<br>phy | Same | Same |
| Power Supply | Medical-grade<br>power supply | Same | Same |
| Patient Safety | Patient connections<br>are isolated from<br>ground | Same | Same |
| Safety and<br>Electrical<br>Standards Met | IEC601-1<br>UL2601-1<br>IEC601.2.26<br>CSA 22.2No.601.1<br>IEC601-1-2 | Not available | IEC601-1<br>IEC601-2-26<br>IEC601-1-2 |
| Recording<br>Capacity | 48-channel capacity<br>including 8 non-<br>isolated AUX DC<br>channels | 40-channel capacity<br>including 8 AUX DC<br>channels | 57-channel capacity<br>including 8 non-<br>isolated AUX DC<br>channels |
| Direct support<br>for an integrated<br>Oximeter | Yes, manufacturer<br>Nonin | Yes, manufacturer<br>Nonin | Yes, manufacturer<br>not specified |
| Calibration/Use<br>Modes | Yes | Yes | Yes |
| Built-in<br>(integrated)<br>electrode<br>impedance test | Yes, results<br>displayed on host<br>controlled LCD<br>display on the device | Yes, results displayed<br>using an array of<br>LEDs on the device | Yes, results<br>displayed on host<br>controlled LEDs on<br>the device |
| Photic (flash<br>unit) | Yes | Yes | Yes |
| Stimulation<br>Control<br>integrated | | | |
| Host Computer<br>to Device<br>Connection | Industry standard<br>Ethernet interface | Same | Same |
| Data Output | Digital | Same | Same |
| Anatomical<br>Sites | Same | Same | Same |
| Technical<br>Characteristic | Grass-Telefactor<br>AS-40 | Bio-logic<br>SleepScan NetLink | Compumedics<br>E-series EEG |
| A/D Resolution | 16-bit, simultaneous<br>sampling | 22-bit, simultaneous<br>sampling | 8, 12, or 16-bit<br>simultaneous<br>sampling |
| Sampling Rate | Up to 800 Hz | 128 - 2048 Hz | Up to 512 Hz |
| Noise | < 2μVpp | < 2μVpp | 0.5μVrms |
| CMRR | >80dB | > 100dB | >115dB differential<br>mode, >105dB<br>single ended |
| Input<br>Impedance | 10 MOhms | Not available | > 100MOhms |
| Low-Frequency<br>Cutoff | 0.16 Hz | 0.1 Hz | 0.16 Hz |
| High-Frequency<br>Cutoff | 100 Hz | Not available | 107 Hz |
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# Comparison Table (Continued)
:
.
:
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## 7. Testing
The Grass-Telefactor AS40 system is in the process of being extensively tested to the applicable safety, EMI and EMC standards for medical electrical devices, and specifically EEG equipment. Third party testing and certification to IEC601-1, IEC601-1-2, IEC601-2-26, UL2601-1, CSA22.2No.601-1 is also in process and will be completed before we commence shipment of this device.
Additional performance testing and bench testing has been completed to verify operation of all functional equipment and performance specifications.
In conclusion, the Grass-Telefactor AS40 amplifier system is as safe and effective as the predicate devices currently marketed by Bio-Logic Corporation and Compumedics and raises no new safety or effectiveness concerns.
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Image /page/6/Picture/1 description: The image is a black and white logo for the Department of Health & Human Services USA. The logo features a stylized eagle with its wings spread, and the words "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" are arranged in a circular pattern around the eagle. The eagle is composed of three curved lines that form the shape of the bird's body and wings.
Food and Drug Administration 10903 New Hampshire Avenue Document Control Room -WO66-G609 Silver Spring, MD 20993-0002
Grass-Telefactor Product Group, Astro-Med, Inc. Peter L. Fuller Assistant Chief Engineer 570 Liberty Street Braintree, Massachusetts 02185
APR - 9 2012
Re: K021807
Trade/Device Name: Grass-Telefactor AS40 Amplifier System Regulation Number: 21 CFR 882.1400 Regulation Name: Electroencephalograph Regulatory Class: II Product Code: OLV, GWQ Dated (Date on orig SE ltr): May 31, 2002 Received (Date on orig SE ltr): June 3, 2002
Dear Mr. Fuller:
This letter corrects our substantially equivalent letter of August 29, 2002.
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.
{7}------------------------------------------------
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 forth in the quality systems (OS) 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/ucm115809.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 (800) 638-2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm.
Sincerely vours.
for
Malvina B. Evdelman, M.D. Director Division of Ophthalmic, Neurological, and Ear, Nose and Throat Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
{8}------------------------------------------------
http://www.fda.gov/cdrh/ode/indicate.html
Page 1 of 1
# 510(k) Number (if known): A
Device Name: Grass-Telefactor AS40 Amplifier System
Indications for Use:
The AS40 amplifier system is designed for use in the recording of routine BBG, overnight sleep/EEG (PSG, Polysomnography), and other neurophysiological monitoring applications (EMG and Evoked Potentials). This device is intended to be used only by physicians, technicians, or other medical professionals that are trained in either electroencephalography or polysomnography.
#### (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)
## Concurence of CDRH, Office of Device Evaulation (ODE)
Prescription Use \$\checkmark\$
Hut R. Rurly (Optional Format 3-10-98)
(Posted July 1, 1998)
Division Sign-Off) Division of General, Restorative and Neurological Devices
510(k) Number K021807
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Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.