The X-trodes System M is intended for prescription use only in the home or healthcare facility to acquire, record, transmit and display physiological signals from adult patients. The X-trodes System M acquires, records, transmits, and displays electroencephalogram (EEG), electrooculogram (EOG), electrocardiogram (ECG), and/or electromyogram (EMG), and accelerometer and gyroscope signals. The X-trodes System M only acquires and displays physiological signals, no claims are being made for analysis of the acquired signals with respect to the accuracy, precision, and reliability.

Device Description

The X-trodes System M combines hardware, firmware, and software to acquire the following physiological signals: physiologic signal amplifier (EEG), electrooculography (EOG), surface electromyography (sEMG), electrocardiography (ECG), and accelerometer and gyroscope signals. It acquires physiological data through a data acquisition unit connected to electrode arrays patches, applied by a technician or patient to the patient. The data is recorded and transmitted to a cloud where it is converted to an EDF (European Data Format) format, suitable for analysis by third party software.

AI/ML Overview

Here's a detailed breakdown of the acceptance criteria and the study that proves the X-trodes System M meets them, based on the provided FDA 510(k) summary:

Acceptance Criteria and Device Performance

The provided document focuses on demonstrating substantial equivalence to predicate devices rather than establishing specific, quantified clinical acceptance criteria for standalone diagnostic accuracy or effectiveness against a clinical gold standard. The "acceptance criteria" can be inferred from the "comparison of technological features" table (Table 1) and the discussion items (Sections 9.1-9.7), where the X-trodes System M's performance characteristics are compared to those of the predicate devices and relevant IEC standards.

The closest thing to a directly stated performance acceptance criterion, beyond comparisons to predicates and standards, is for the clinical study's primary endpoint:

Primary Study Endpoint (Infered Acceptance Criterion): A high proportion of interpretable readings of each ExG signal (ECG, EEG, EMG, EOG) by the X-trodes System M that are equivalent to those of the reference device, with lower 98.75% confidence intervals higher than 60%.

Feature/Metric	Acceptance Criteria (from Predicate comparison/Standards)	Reported Device Performance (X-trodes System M)	Comments/Reference
Full Scale Input Range	Sufficient for EEG (10-100 µV), ECG (10 µV-5 mV), and EMG (0-10 mV)	± 12.5 mV	Well within required range for all modalities (Sec. 9.1)
A/D Conversion	Sufficient resolution to capture physiological signals (e.g., 16 bits for ECG for many cleared devices, 24 bits for predicates)	16 bits	Adequate resolution, especially for AC-coupled signals (Sec. 9.2)
Sampling Frequency (Rate)	At least 220% of max sampled frequency (Nyquist)	4000 Hz/Channel	Exceeds required sampling rate for its broader frequency range (Sec. 9.3)
Frequency Response	Linear between 0.1 and 100 Hz (EEG/EOG Predicate), 0.01 Hz ~ 350 Hz (-3 dB) (ECG Predicate)	0.35 Hz ~ 700 Hz (-3 dB)	Supersedes predicates' ranges (Table 1)
Input Impedance	≥10 MΩ (EEG Predicate), ≥100 MΩ (ECG/EMG Predicate), ≥2.5 MΩ (IEC60601-2-25)	≥10 MΩ	Complies with IEC standard and comparable to predicate (Sec. 9.4)
DC Offset Voltage	Tolerant to DC offset (e.g., ±960mV for ECG predicate)	+3000mV, -1000mV ±5%	Broader range, more tolerant to DC offset (Sec. 9.5)
Noise	<0.6 µV RMS (EEG Predicate), <12.5 µVp-p (ECG Predicate), <0.6 µVrms (EMG Predicate), IEC60601-2-26 EEG standard, IEC60601-2-25 ECG standard	<0.9 µV RMS, 1-35 Hz (EEG), ≤6 µVp-p 0.5-50Hz (EEG); <30 µV peak-to-valley (ECG/EMG)	Meets ECG noise standard, acceptable for EEG/EMG with clinical demonstration (Sec. 9.6)
CMRR	>90 dB (EEG Predicate), ≥140 dB (ECG Predicate), >100 dB (EMG Predicate)	>95 dB at 60 Hz/50Hz	Complies with IEC60601-2-26 EEG and IEC60601-2-25 ECG standards (>90dB) (Sec. 9.7)
Primary Clinical Endpoint	Agreement proportion for each ExG signal with reference device, with lower 98.75% CI > 60%	ECG: 89.36%, EEG: 97.37%, EMG: 96.15%, EOG: 95.24%. All lower 98.75% CIs > 60%.	Primary endpoint successfully met (Sec. 11)
Secondary Clinical Endpoint	Consistency and reliability of RMS values	RMS values obtained and compared	Demonstrates consistency and reliability (Sec. 11)

Study Details

The document describes a clinical study to demonstrate the X-trodes System M's performance compared to an FDA-cleared clinical electrophysiology device.

Sample Size used for the test set and the data provenance:
- Sample Size: 55 subjects.
- Data Provenance: The study was a "case-controlled study" conducted in a "clinic environment." The subjects were "adults who had been referred by either a neurologist for an electrophysiology test in the last 5 years." This suggests the data is prospective, collected specifically for this study, and likely from a single or limited number of clinical sites. The country of origin is not explicitly stated, but the applicant's address is Herzliya, Israel, which might imply the study was conducted there or in the US.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- The study design describes a comparison against an "FDA-cleared clinical electrophysiology device" (referred to as X8). The "interpretability" and "equivalency" of XTR signals to the reference device were assessed.
- The document does not explicitly state the number or qualifications of experts used to establish the ground truth or determine the "interpretable readings" and "equivalency" for the test set. It implies the reference device (X8) provided the comparison standard, and then the XTR signals were evaluated against that. It's unclear if independent human experts adjudicated the signals from both devices or if a software-based comparison was used for "equivalency."
Adjudication method for the test set:
- The document states "The primary study endpoint was the proportion of interpretable readings of each ExG signal by the XTR that are equivalent to those of the reference device."
- The specific adjudication method (e.g., 2+1, 3+1, none) is not detailed in the provided text. It's unclear how "interpretability" and "equivalency" were precisely determined.
If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
- No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. The study was a comparison of the X-trodes System M (the subject device) against another predicate device (X8) and focused on signal acquisition and display, not on the impact of an AI algorithm on human reader performance. The device "only acquires and displays physiological signals, no claims are being made for analysis of the acquired signals with respect to the accuracy, precision, and reliability." Therefore, there is no AI assistance component to measure the effect size for human readers.
If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- Yes, in spirit, a standalone performance assessment was conducted for the device's signal acquisition capabilities. The study directly compared the signals acquired by the X-trodes System M to a reference device. It's "algorithm only" in the sense that the device itself acquires and processes the signals for display, and its performance (interpretable readings, RMS values) was directly evaluated without a human-in-the-loop task for diagnosis. However, it's crucial to note that the device does not perform analysis or provide diagnostic output; it just collects and displays signals.
The type of ground truth used:
- The "ground truth" was established by an FDA-cleared clinical electrophysiology device (X8). The X-trodes System M's acquired physiological signals (EEG, EOG, ECG, EMG) were compared for "interpretable readings" and "equivalency" against the signals simultaneously acquired by the X8 device. This is a comparative ground truth against an established device, rather than a clinical outcome or pathology report.
The sample size for the training set:
- The document does not provide information on a training set sample size. This makes sense as the device is stated to "only acquires and displays physiological signals, no claims are being made for analysis of the acquired signals," implying it's not an AI/ML-driven device that typically requires a dedicated training set for diagnostic or analytical tasks. The performance evaluation focused on the device's ability to accurately capture and display raw physiological signals.
How the ground truth for the training set was established:
- As no information on an AI/ML training set is provided (and the device is described as not performing analysis), there is no mention of how ground truth for a training set was established.

Summary

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February 4, 2024

Image /page/0/Picture/1 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). On the left, there is a symbol representing the Department of Health & Human Services-USA. To the right, the FDA logo is displayed in blue, with the words "U.S. FOOD & DRUG ADMINISTRATION" written in a clear, sans-serif font. The overall design is clean and professional, reflecting the organization's role in public health and safety.

X-Trodes % Donna-Bea Tillman Senior Consultant Biologics Consulting Group 100 Daingerfield Rd, Suite 400 Alexandria, VA 22314

Re: K232210

Trade/Device Name: X-trodes System M Regulation Number: 21 CFR 882.1835 Regulation Name: Physiological Signal Amplifier Regulatory Class: Class II Product Code: GWL, GXY, DPS, IKN Dated: January 4, 2024 Received: January 4, 2024

Dear Donna-Bea Tillman:

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 (the 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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.

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Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).

Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30. Design controls; 21 CFR 820.90. Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).

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 of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Patrick Antkowiak -S for Jay Gupta Assistant Director

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DHT5A: Division of Neurosurgical, Neurointerventional and Neurodiagnostic Devices OHT5: Office of Neurological and Physical Medicine Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K232210/S001

Device Name X-trodes System M

Indications for Use (Describe)

X Prescription Use (Part 21 CFR 801 Subpart D)

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

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1. SUBMITTER INFORMATION

Applicant:	X-trodes
Contact:	Ziv Peremen, Ph.D
Phone:	+972 54 2244811
Email:	Ziv@xtrodes.com
Address	4 Maskit St.Herzliya, Israel

2. CORRESPONDENT INFORMATION

Contact:	Donna-Bea Tillman, Ph.D.
Title:	Senior Consultant
Firm:	Biologics Consulting Group

3. -DATE PREPARED: FEBRUARY 2, 2024

4. DEVICE INFORMATION

Device Name:	X-trodes System M
Common Name:	Reduced-Montage StandardElectroencephalograph
Regulation Number:	21 CFR 882.1835

Regulation Name:	Physiological signal amplifier
Primary Product Code:	GWL
Secondary Product:Codes	GXY, DPS, IKN
Regulatory Class:	Class II

5. PREDICATE DEVICE INFORMATION

Primary EEG/EOG Predicate Device Name:	Quick-20m
510(k) Number:	K203331
Manufacturer:	CGX, LLC

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ECG Predicate Device Name:	Electrocardiograph (SE-1200 Pro, SE-1201 Pro)
510(k) Number:	K222902
Manufacturer:	Edan Instruments, Inc.
EMG Predicate Device Name:	Focus EMG
510(k) Number:	K102610
Manufacturer:	TeleEMG, LLC

The predicate devices have not been subject to a design related recall.

DEVICE DESCRIPTION 6.

7. INDICATIONS FOR USE

The X-trodes System M is intended for prescription use only in the home, healthcare facility, or clinical research environment to acquire, record, transmit and display physiological signals from adult patients. The X-trodes System M acquires, records, transmits, and displays electroencephalogram (EEG), electrooculogram (EOG), electrocardiogram (ECG), and/or electromyogram (EMG), and accelerometer and gyroscope signals. The X-trodes system M only acquires and displays physiological signals, no claims are being made for analysis of the acquired signals with respect to the accuracy, precision, and reliability.

COMPARISON OF INTENDED USE AND TECHNOLOGICAL 8. CHARACTERISTICS WITH THE PREDICATE DEVICE

The table below compares the intended use and the technological characteristics of the subject device and predicate device.

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	Subject Device	Primary PredicateEEG/EOG	Predicate ECG	Predicate EMG	Comments
510(k) Number	K232210	K203331	K222902	K102610
Applicant	Xtrodes Ltd.	CGX, LLC	Edan Instruments, Inc.	TeleEMG, LLC
Device Name	X-trodes System M	Quick-20m	Electrocardiograph (SE-1200 Pro, SE-1201 Pro)	Focus EMG
ClassificationRegulation	21 CFR 882.1835Physiological signal	21 CFR 882.1835Physiological signal	21 CFR 870.2340Electrocardiograph	21 CFR 890.1375Diagnostic
	amplifier21 CFR 882.1320Cutaneous Electrode21 CFR 870.2340Electrocardiograph21 CFR 890.1375DiagnosticElectromyograph	amplifier21 CFR 882.1320Cutaneous Electrode		Electromyograph
Product Code	GWL, GXY, DPS, IKN	GWL, GXY	DPS	IKN
Intended Use	The X-trodes System M isintended for prescriptionuse only in the home,healthcare facility, orclinical researchenvironment to acquire,record, transmit anddisplay physiologicalsignals from adult patients.The X-trodes System Macquires, records,transmits, and displayselectroencephalogram(EEG), electrooculogram(EOG), electrocardiogram(ECG), and/orelectromyogram (EMG),and accelerometer andgyroscope signals. The X-trodes System M only	The Quick-20m isintended to be used toacquireelectroencephalograph(EEG) and transmit itwirelessly to a computer.	The SE-1200 Pro&SE-1201 Pro 12-leadelectrocardiographs areintended to acquire ECGsignals from adult andpediatric patients throughbody surface ECGelectrodes. Theelectrocardiographs areonly intended to be usedin hospitals or healthcarefacilities by doctors andtrained healthcareprofessionals. Thecardiogram recorded bythe electrocardiograph canhelp users to analyze anddiagnose heart disease.However, the interpretedECG with measurements	The Focus is intended foruse by a healthcareprovider to perform nerveconductions and EMGstudies as an aid in theevaluation of patientswith diseases of muscleand nerves. The machinecan also use electricalstimulus or soundstimulus for evokedpotentials (EP) studies.
	Subject Device	Primary PredicateEEG/EOG	Predicate ECG	Predicate EMG	Comments
	acquires and displaysphysiological signals, noclaims are being made foranalysis of the acquiredsignals with respect to theaccuracy, precision, andreliability.		and interpretivestatements is offered toclinicians on an advisorybasis only.
PatientPopulation	Adults	Adults	Adult and pediatricpatients	Adults	Same
Environment ofUse	Home, Healthcarefacility,	Home or healthcarefacility setting	Hospitals or healthcarefacilities	Clinical environment.	The subject device and theprimary predicate device areintended for use in eitherhealthcare facility or homesettings
Signals Acquired	Forehead/head EEG, EOG,EMG, ECG, Microphone,Accelerometer, Gyroscope	EEG/EOG	ECG	EMG	The subject device is acombination of the featuresof the predicate devices
Full scale InputRange	± 12.5 mV	± 300 mV	No information in thepredicate 510(k)Summary	No information in thepredicate 510(k)Summary	See Discussion item 1
A/D conversion	16 bits	24 bits	24 bits	16 Bits	Same for EMGSee Discussion item 2
SamplingFrequency (Rate)	4000 Hz/Channel	500 Hz/channel	64,000 Hz	200-80000 Hz	See Discussion item 3
FrequencyResponse	0.35 Hz ~ 700 Hz (-3 dB)	Linear between 0.1and 100 Hz	0.01 Hz ~ 350 Hz (-3 dB)	No information in thepredicate 510(k)	XTR frequency rangesupersedes the predicates,thus constitutes SE.
Input Impedance	≥10 MΩ	>100 MOhm (125 Hz)	≥100 MΩ(10 Hz)	≥100 MOhm< 25pF	See Discussion item 4
DC Offset Voltage	+3000mV, -1000mV ±5%.	No information in thepredicate 510(k)	±960mV, ±5%	No information in thepredicate 510(k)	See Discussion item 5
Noise	<0.9 µV RMS,1-35 Hz≤6 µVp-p 0.5-50Hz	<0.6 µV RMS,1-30 Hz	≤12.5 µVp-p	< 0. 6 µVrms	See Discussion item 6
Filter	Analog: 0.35-700Hz	DC up to 131 Hz	AC Filter:50 Hz / 60 Hz / Off	Low pass filter:	Analog filter is applied priorto A/D conversion.
	Subject Device	Primary PredicateEEG/EOG	Predicate ECG	Predicate EMG	Comments
	Digital display filters:EEG: 0.32-35 HzEOG: 0.32-35 HzECG: 0.32-70 HzEMG: 10-114 Hz		DFT Filter:0.01 Hz / 0.05 Hz / 0.32Hz / 0.67 HzEMG Filter:25Hz / 35Hz / 45Hz /OFFLOWPASS Filter:350 Hz / 300 Hz / 270 Hz/ 150 Hz / 100 Hz/ 75 Hz	(-12dB/octave) 10 to10,000High pass filter:(-6dB/octave) 0.05 to3000 Hz	Data is delivered raw.Modality Filters are appliedfor Real-time display only.
Notch filter	50/60 Hz selectable	No information in thepredicate 510(k)	No information in thepredicate 510(k)	50/60 Hz selectable	Filters are applied for Real-time display only.
CMRR	>95 dB at 60 Hz/50Hz	>90 dB at 60 Hz	≥140 dB (AC filter on)≥123 dB (AC filter off)	>100 dB	For EEG - Similar topredicatesFor ECG and EMGSee Discussion item 7
Connection	Bluetooth Low Energy	Wireless to receiver, USBto computer	WIFI, 4G, Bluetooth	USB to computer	Similar to predicates
Number OfPossibleElectrodes	16	20 Channels instandard 10-20 headmap	10	2	Similar to predicates range.Differ for each predicate forthe differentelectrophysiological signalapplication
Type ofElectrodes	Dry	Dry	Body surface ECGelectrodes	Stainless steel electrodes.No additional informationis supplied in thepredicate 510(k) summary	Similar to the EEG/EOGpredicate.FDA has found dryelectrodes to besubstantially equivalent togel electrodes.
Type Of AppliedPart	CF	BF	CF	No information in thepredicate 510(k)	Similar to predicates

Table 1: Comparison of Technological Features

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9. PREDICATE DEVICE DISCUSSION ITEMS

1. Full Scale Input Range

A typical adult human EEG signal is about 10 µV to 100 µV in, so even if we consider 10-fold increase to this range (1mV), it is well covered within the X-trodes device's inputs range of 12.5 mV. Any input range larger than that is unnecessary.

For ECG, there is no information about the predicate device's input range. Therefore, we aim to establish that the X-trodes device has an input range suitable for ECG. "Normal ECG signals are time-varying signals with a small amplitude ranging from 10 µV to 5 mV" (cited from PubMed PMC7664289). The X-trodes device's input range of 12.5 mV is more than double this range.

For EMG, there is no information about the predicate device's input range. Therefore, we aim to establish that the X-trodes device has an input range suitable for EMG. "The amplitude range of EMG signal is 0-10 mV (+5 to -5) prior to amplification" (cited from PubMed PMC1455479). X-trodes device's input range of 12.5 mV is more than double this range.

Lastly, the results of the clinical study presented in Section 20 of the Original 510(k) submission demonstrate that the quality of the EEG/ECG/EOG/EMG waveforms is sufficient for clinical purposes. Taken together, these considerations are sufficient to demonstrate that the X-trodes device is substantially equivalent to the predicates in this aspect.

2. A/D conversion

For EEG, a typical adult human EEG signal is about 10 µV to 100 µV. If we consider 10fold this signal, it takes constitutes a portion of about 1000µV (1/300) of the predicate device's input range.

For ECG, there is no information about the predicate devices input range. However, based on the DC offset of the predicate device, we assume it to be 960mV, to cater for handling this DC offset. Since the X-Trodes device is AC coupled, it has no need to digitize all this vast DC range and ADC conversion is applied only on the AC signal.

A typical adult human ECG signal, which is about 5mV amplitude. It constitutes a portion of about 5mV/960mV (0.0166) of the assumed input range. This portion practically utilizes only 17 bits out of its 24-bit resolution, according to the following calculation:

Quantization step is 960,000μV/(2^24-1)= 0.057μV.

Digital representation of 5mV would be 5000uV/0.057μV=87,381 (binary 1 0101 0101 0101 0101) which is 17 bits.

FDA has also cleared many ECG devices that have a 16-bit resolution.

3. Sampling frequency (Rate)

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Sampling rate should be considered in conjunction with the frequency response and should be at least 220% of the max sampled frequency to practically comply with Nyquist's law of digitation.

Therefore, the discussion should be whether the device has sufficient sampling rate to cover its frequency range. The X-Trodes device has a frequency range of 750Hz, which is broader than the predicate device's (350Hz). This frequency range can be accommodated by a sampling rate of 1.650Hz. Therefore, the X-Trodes device's sampling rate of 4KHz exceeds the required sampling rate and qualifies as substantially equivalent in this aspect.

In addition, the results of the clinical study presented in Section 20 of the Original 510(k) submission demonstrate that the quality of the EEG/ECG/EOG/EMG waveforms is sufficient for clinical purposes. Taken together, these considerations are sufficient to demonstrate that the Xtrodes device is substantially equivalent to the predicates in this aspect.

4. Input impedance

The input impedance of the X-Trodes device complies with clause 201.12.4.103 of the IEC60601-2-25 ECG standard which states that "The input impedance shall be at least 2,5 MS2 within a d.c. offset voltage range of ±300 mV".

In addition, FDA has cleared EEG devices such as the Digital NeuroPort Biopotential Signal Processing System(K202174) that also have an input impedance of ≥10 MΩ.

5. DC offset

The X-Trodes device is AC coupled, thus its DC offset limits are derived from the OV/UV protection devices which are set at +3.0v and -1 V. This DC offset range is broader than the predicate's DC offset range, rendering the XTR system more tolerant to DC offset, thus the Xtrodes device is substantially equivalent in this aspect.

6. Noise

For ECG, the X-trodes device's noise is smaller than the predicate device's, thus constitutes substantial equivalence.

For EEG, the X-trodes device's noise is slightly higher than the predicate device, however it relates to only a portion of the EEG spectrum. Furthermore, the overall noise performance over the full EEG spectrum of the X-trodes device, complies with the IEC60601-2-26 EEG standard as shown in the Bench Test Report.

For EMG, the X-trodes device's noise is slightly higher than the predicate device's, however, it was demonstrated in the clinical trial that the measured EMG signal was of the required signal quality. Moreover, since there is no standard noise requirement for EMG, and since EMG signal's dynamic input range is similar to ECG, compliance with ECG noise standard can fulfill this requirement. The X-Trodes device complies with ECG noise requirement of 30 µ V peak-tovalley referred to the input (IEC60601-2-25). Therefore, the X-Trodes device is substantially equivalent in this aspect.

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7. CMRR

The X-Trodes device CMRR complies with the applicable provisions for both- IEC60601-2-26 EEG and IEC60601-2-25 ECG standards of CMRR > 90db, which constitutes adequate performance.

Conclusion

In conclusion, the subject X-trodes device has the same intended use as the proposed predicate devices, that is to acquire and display electrophysiological data. While there are technological differences, these differences do not raise different questions of safety and effectiveness, and therefore the predicate devices can serve as predicate devices for the X-trodes 510(k).

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10. SUMMARY OF NON-CLINICAL PERFORMANCE TESTING

Biocompatibility Testing

The only patient-contacting component of the X-trodes System M is the XTR Electrode patches. The Xtrodes System M is classified as a surface medical device, in contact with intact skin for less than 24 hours. The following biocompatibility testing was conducted:

Sensitization, ISO 10993-10:2021
Irritation, ISO 10993-23:2021
Cytotoxicity, ISO 10993-5:2009

Electrical Safety

The following tests were conducted:

IEC 60601-1:2005 (3rd ed) + CORR. 1:2006 + CORR.2:2007+A1:2012, Medical electrical equipment: Part 1: General requirements for basic safety and essential performance, including US deviations

IEC 62133-2:2017, Secondary cells and batteries containing alkaline or other non-acid electrolytes – Safety requirements for portable secondary cells, and for batteries made from them, for use in portable applications – Part 2: Lithium systems

IEC 60601-2-25:2011, Medical electrical equipment – Part 2-25: Particular requirements for the basic safety and essential performance of electrocardiographs

ISO/IEC 80601-2-26:2019, Particular requirements for the basic safety and essential performance of electroencephalographs

IEC 60601-2-40:2016, Particular requirements for the basic safety and essential performance of electromyographs and evoked response equipment

Electromagnetic Compatibility (EMC)

The following tests were conducted:

AAMI TIR69:2017, Risk management of radio-frequency wireless coexistence for medical devices and systems

ANSI/IEEE C63.27:2017, Evaluation of Wireless Coexistence

IEC 60601-1-2:2014+A1:2020/Ed. 4.1, Medical electrical equipment – Part 1-2: General requirements for basic safety and essential performance – Collateral Standard: electromagnetic disturbances – Requirements and tests

Software

Software was evaluated for a moderate level of concern as recommended in the 2005 FDA guidance document Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices.

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Performance Testing

Other performance testing was conducted to show that the device meets its design requirements and performs as intended. The performance tests include:

IEC 60601-1-6:2020. Medical electrical equipment - Part I-6: General requirements for basic safety and essential performance - Collateral standard: Usability

Human factors testing in accordance with the FDA guidance document, Applying Human Factors and Usability Engineering to Medical Devices.

SUMMARY OF CLINICAL TESTING 11.

X-trodes conducted a study to evaluate the accuracy and consistency of the X-trodes System M compared to an FDA-cleared clinical electrophysiology device.

Methods: X-trodes conducted a case-controlled study of 55 subjects who wore the subject and reference devices (X8) simultaneously. The test duration was approximately 20 minutes and was conducted in a clinic environment. There was a one minute preliminary screening evaluation to determine that electrode conductivity was established and then four minutes of data collection for each modality. Study subjects were adults who had been referred by either a neurologist for an electrophysiology test in the last 5 years.

Results: The primary study endpoint was the proportion of interpretable readings of each ExG signal by the XTR that are equivalent to those of the reference device. The agreement proportion for the ECG was 89.36%, for the EEG 97.37%, for the EMG 96.15% and for the EOG 95.24%. All lower 98.75% confidence intervals are higher than 60%. Taking into consideration the high agreement proportions per signal modality and the high CI, it can be concluded that the primary end point was met successfully.

For the secondary end point, each modality, the characteristic signal was quantified, and the RMS values were obtained by comparing the signals captured by the X-trodes and X8 devices. The results demonstrate the consistency and reliability of the measurements obtained from the devices and provide an indication of the level of agreement between them.

Conclusions: The comparison between the X-trodes XTR and the predicate device demonstrates that the XTR satisfied the pre-specified performance criteria and thus can be found substantially equivalent to the X8 sleep profiler PSG.

12. CONCLUSION

The results of the performance testing described above demonstrate that the X-trodes System is as safe and effective as the predicate device and supports a determination of substantial equivalence.

Regulation Number and Section

§ 882.1835 Physiological signal amplifier.

(a)
Identification. A physiological signal amplifier is a general purpose device used to electrically amplify signals derived from various physiological sources (e.g., the electroencephalogram).(b)
Classification. Class II (performance standards).