The noninvasive FORE-SIGHT ELITE Tissue Oximeter "Module" is intended for use as an adjunct monitor of absolute regional hemoglobin oxygen saturation of blood under the sensors in individuals at risk for reduced flow or no-flow ischemic states. The Module is also intended for use as an adjunct monitor of relative changes of oxygenated hemoglobin, deoxygenated hemoglobin, and their summation, total hemoglobin, of blood under the sensors. The Module is intended to allow for the display of StO2 and regional hemoglobin on a third party display/patient monitor and is indicated for use as follows:

When used with large sensors, the Module is indicated for use on adults and transitional adolescents ≥40 kg. When used with medium sensors, the Module is indicated for use on pediatric subjects ≥3 kg. When used with small sensors, the Module is indicated for cerebral use on pediatric subjects < 8 kg and non-cerebral use on pediatric subjects < 5kg.

Device Description

The FORE-SIGHT ELITE Tissue Oximeter Module measures hemoglobin under the Sensor, allowing the clinician to continuously and accurately determine absolute levels of blood oxygenation saturation in the tissue (StO2). The Module additionally measures relative changes in oxygenated and deoxygenated hemoglobin concentrations for assessment of oxygenation changes as well as their sum, total hemoglobin concentration, under the sensor.

The Oximeter Module consists of a signal acquisition and processing unit, power isolation box, host power and communication cables, and sensor cables to connect with FDA cleared FORE-SIGHT ELITE small, medium and large sensors. The Sensors use multiple wavelengths in the range of 660 to 900 nm to precisely measure light absorption in tissue. Sensors are sized to provide targeted penetration depths appropriate for the tissue and patient populations of interest. The Module controls the measurement sequence, generating the sensor LED currents and processing the detected light signals after amplification. The FORE-SIGHT algorithm determines the StO2 values for the tissue under the sensor from the light absorption values and measured patient characteristics. The Module provides simultaneous measurements on up to two Sensors.

The Module is a host-powered device. The host configures the Oximeter and provides applicable audible, on-screen, and dedicated visual alarm indicators. The host monitor also provides numeric and/or realtime graphical display for tissue blood oxygenation saturation and changes in hemoglobin concentrations. Measurement data is delivered to the host through various interfaces including USB and serial connections.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study information for the FORE-SIGHT ELITE Tissue Oximeter Module, based on the provided text:

Acceptance Criteria and Reported Device Performance

The document does not explicitly present a table of quantitative acceptance criteria with corresponding performance metrics in a pass/fail format. Instead, it describes various validation studies demonstrating the device's accuracy against reference methods across different patient populations and measurement types. The core acceptance is based on demonstrating substantial equivalence to a predicate device (K180003) and a reference device (K143219), particularly for the new feature of measuring relative changes in hemoglobin concentrations.

However, the "Type Measurement" and "Reference" columns in Table 1: StO2 and Changes in Hemoglobin Concentration Validation Methodology implicitly define the performance metrics and the ranges over which the device was validated. The success of these validations, as stated in the "Conclusions Drawn from Clinical and Non-Clinical Testing," indicates that the device met the internal criteria used to establish substantial equivalence.

Here’s an interpretation of the performance and the implied criteria based on Table 1:

Patient Population	Sensor	Parameter	Implied Acceptance Criteria (Range of Reference)	Reported Device Performance (Implied by "successfully undergone extensive clinical validation" and "high precision")
Adult	Large	StO2	48 to 88% (Cerebral), 50 to 90% (Non-Cerebral)	Demonstrated substantial equivalence to predicate for StO2 measurements.
		ΔHHb, ΔO₂Hb	±5 g/dL, ±19 μM (Cerebral/Non-Cerebral)	High precision to co-oximetry blood sample references.
Pediatric	Medium	StO2	48 to 92% (Cerebral), 53 to 88% (Non-Cerebral)	Demonstrated substantial equivalence to predicate for StO2 measurements.
		ΔHHb, ΔO₂Hb	0 to 2 g/dL, 7.4 uM (Co-oximetry), ±85 μM (Phantom)	Evaluated using convenience co-oximetry and frequency domain oximeter on phantom.
Pediatric	Small	StO2	50 to 90% (Cerebral), 66 to 96% (Non-Cerebral)	Demonstrated substantial equivalence to predicate for StO2 measurements.
		ΔHHb, ΔO₂Hb	±85 μM (Phantom)	Demonstrated equivalence to NIRO-200NX reference device and concurrent frequency domain oximetry.
Neonates	Small	StO2	50 to 90% (Cerebral, FORE-SIGHT MC3010), 66 to 96% (Non-Cerebral)	StO2 data averaged in two-minute windows for stability.
		ΔHHb, ΔO₂Hb	±85 μM (Phantom)	Demonstrated equivalence to NIRO-200NX reference device and concurrent frequency domain oximetry.

2. Sample Sizes Used for the Test Set and Data Provenance

The document provides specific sample sizes for some of the validation groups, particularly for the healthy adult volunteers and cardiac surgical patients. It also indicates the demographic breakdown of these subjects.

Adult StO2 Validation (Healthy Adult Volunteers, Table 1 footnote 1):
- Sample Size: 25 healthy adult volunteers (12 Male, 13 Female)
- Data Provenance: Healthy adult volunteers, presumably within the US or a similar regulatory environment, prospective collection for the study.
Adult ΔHHb, ΔO₂Hb Validation (Healthy Volunteers, Table 1 footnote 2):
- Sample Size: 43 healthy volunteer subjects (22 Male, 21 Female)
- Data Provenance: Healthy adult volunteers, presumably within the US or a similar regulatory environment, prospective collection for the study.
Adult ΔHHb, ΔO₂Hb Validation (Cardiac Surgical Patients, Table 1 footnote 2):
- Sample Size: 5 cardiac surgical patients (3 Male, 2 Female)
- Data Provenance: Convenience sample measurements from cardiac surgical patients undergoing cardiopulmonary bypass procedures, retrospective or prospective (convenience sample often implies retrospective use of available data, but could be prospective for the study).
Pediatric ΔHHb, ΔO₂Hb Validation (Cardiac Surgical Patients, Table 1 footnote 3):
- Sample Size: No specific number for cardiac surgical patients for ΔHHb, ΔO₂Hb.
- Data Provenance: Evaluated using convenience samples.
Pediatric StO2 Validation (Interventional Catheterization, Table 1 footnote 3):
- Sample Size: 5 pediatric patients (4 Male, 1 Female)
- Data Provenance: Pediatric patients undergoing interventional catheterization procedures, prospective collection for the study.
Neonatal StO2 Validation (No specific number mentioned, Table 1 footnote 5):
- Sample Size: Not explicitly stated but refers to "term, premature low birth weight (LBW), and very low birth weight (VLBW) neonates."
- Data Provenance: Clinical study, possibly prospective.
Liquid Optical Phantom Validation:
- Sample Size: Not applicable, involves optical phantoms rather than human subjects.
- Data Provenance: Laboratory testing.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

The document does not specify the "number of experts" or their "qualifications" involved in establishing the ground truth. However, the ground truth itself (co-oximetry blood samples) is considered a gold standard, and its analysis would typically be performed by trained clinical laboratory personnel according to established protocols, rather than requiring an "expert panel" for interpretation in the same way an imaging study would.

4. Adjudication Method for the Test Set

Not applicable. The ground truth for this device (StO2 and hemoglobin concentrations) is established directly through co-oximetry blood samples and optical phantom measurements, which are objective and quantitative measurements, not subject to subjective interpretation and thus do not require an adjudication method among experts.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No. This is not an imaging device that would typically involve human readers interpreting cases. It is a physiological monitoring device with quantitative output. Therefore, an MRMC study comparing human readers with and without AI assistance is not relevant to this submission.

6. Standalone (Algorithm Only) Performance Study

Yes, in essence. The clinical validation studies described represent the standalone performance of the device's algorithm in measuring StO2 and changes in hemoglobin concentrations against a physical ground truth (co-oximetry and optical phantoms). The "Module controls the measurement sequence, generating the sensor LED currents and processing the detected light signals after amplification. The FORE-SIGHT algorithm determines the StO2 values...". This directly describes standalone algorithm performance.

7. Type of Ground Truth Used

The primary ground truth used is:

Co-oximetry of blood samples: Considered the gold standard for measuring oxygen saturation and hemoglobin concentrations in blood. This was used for both cerebral and non-cerebral measurements across adult and pediatric populations.
Frequency domain oximeter on liquid optical phantom: Used as a reference to validate the differential changes in hemoglobin concentrations (ΔHHb, ΔO₂Hb), particularly for the smaller sensors and pediatric/neonatal populations where invasive blood sampling might be more challenging.
FORE-SIGHT MC3010: Used as a reference for StO2 measurements in neonates, indicating a comparison to an established device.

8. Sample Size for the Training Set

The document does not explicitly mention a "training set" or its sample size. The description of the device as "identical to the primary predicate device K180003 with the singular addition of software enhancement for the processing and display for relative changes in hemoglobin concentrations" suggests that the core algorithm for StO2 was already established and validated in previous submissions (K180003 and "earlier CASMED Premarket Notifications"). The focus here is on the validation of the enhanced software and the new parameters (ΔHHb, ΔO₂Hb).

For new algorithms, particularly those using machine learning, a training set would be explicitly detailed. The method described here is more akin to traditional medical device validation, where the algorithm is developed based on known physiological principles and validated against ground truth. If there was an implicit "training" or "development" dataset, it is not described in this 510(k) summary.

9. How the Ground Truth for the Training Set Was Established

Since an explicit "training set" and its establishment are not detailed, this question cannot be answered directly from the provided text. The device's algorithm appears to be based on established spectroscopic principles for measuring tissue oxygenation rather than a data-driven machine learning approach that would typically involve a distinct training set. The "validation studies" mentioned are for testing the performance of the already developed algorithm.

Summary

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October 21, 2019

CAS Medical Systems, Inc. Ron Jeffrey Director, Regulatory Affairs 44 East Industrial Road Branford, Connecticut 06405

Re: K190270

Trade/Device Name: FORE-SIGHT ELITE Tissue Oximeter Module Regulation Number: 21 CFR 870.2700 Regulation Name: Oximeter Regulatory Class: Class II Product Code: MUD Dated: February 6, 2019 Received: February 8, 2019

Dear Ron Jeffrey:

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. 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 located 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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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 803) for devices or postmarketing safety reporting (21 CFR 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 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 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 medical devices and radiation-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.

Purva Pandya Acting Assistant Director DHT4A: Division of General Surgery Devices OHT4: Office of Surgical and Infection Control 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) K190270

Device Name

FORE-SIGHT ELITE Tissue Oximeter Module

Indications for Use (Describe)

Type of Use (Select one or both, as applicable)	.	A MISSA MARKA A MALA A MAJA JA JA PE SE A A A PERSON SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE SE S	------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
	17 Personal de 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11

Prescription Use (Part 21 CFR 801 Subpart D)

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

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K190270

510(k) Summary

510(k) SUMMARY OF SAFETY AND EFFECTIVENESS

Submitter:	CAS Medical Systems, Inc.
Address:	44 East Industrial Rd. Branford CT. 06405 USA
Contact:	Ron Jeffrey – Director, Regulatory AffairsPhone - (203) 488-6056Fax – (203) 488-9438Email – rjeffrey@casmed.com
Prepared:	February 6, 2019
Trade Name:	FORE-SIGHT ELITE® Tissue Oximeter Module
Common Name:	FORE-SIGHT ELITE Module
Classification Name:	Oximeter, Tissue Saturation (870.2700) (MUD)

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EQUIVALENCE (Predicate Device)

The FORE-SIGHT ELITE® Tissue Oximeter Module is equivalent to the following device:

FORE-SIGHT ELITE Tissue Oximeter Module (K180003);

REFERENCE DEVICE

Hamamatsu Photonics Niro-200NX (K143219); ●

DESCRIPTION

FORE-SIGHT Oximeter Monitor Intended Use

The noninvasive FORE-SIGHT ELITE Tissue Oximeter Module is intended for use as an adjunct monitor of absolute regional hemoglobin oxygen saturation of blood under the sensors in individuals at risk for reduced flow or no-flow ischemic states. The Module is also intended for use as an adjunct monitor of relative changes of oxygenated hemoglobin, deoxygenated hemoglobin, and their summation, total hemoglobin, of blood under the sensors. The Module is intended to allow for the display of StO2 and regional hemoglobin on a third party display/patient monitor and is indicated for use as follows: When used with large sensors, the Module is indicated for use on adults and transitional adolescents ≥40 kg. When used with medium sensors, the Module is indicated for use on pediatric subjects ≥3 kg. When used with small sensors, the Module is indicated for cerebral use on pediatric subjects < 8 kg and noncerebral use on pediatric subjects <5kg.

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FORE-SIGHT Module Technology Compared to Predicate Devices

The proposed FORE-SIGHT ELITE Tissue Oximeter Module is identical to the primary predicate device K180003 with the singular addition of software enhancement for the processing and display for relative changes in hemoglobin concentrations in addition to %StO2. Relative changes in hemoglobin concentrations are derived and displayed much the same as the NIRO-200NX reference device (K143219). The Module allows integration into CASMED and third-party monitoring systems.

The proposed FORE-SIGHT ELITE Tissue Oximeter Module and the predicate Module (K180003) use the same Sensors. The FORE-SIGHT ELITE Tissue Oximeter Module uses the same multi-distance diffuse reflectance spectroscopy operating principle. All cited monitors use light to examine a crosssection tissue microvasculature (a mixed bed of arterioles, capillaries and venules). The FORE-SIGHT ELITE Module and predicate devices analyze the light that is returned after having passed through tissues. The spectroscopic analysis determines concentrations of hemoglobin in its oxygenated and deoxygenated states. All cited monitors calculate oxygen saturation which reflects the percentage of oxygenated hemoglobin in the sampled tissue with the proposed Module and reference device additionally computing relative changes in hemoglobin concentrations.

The FORE-SIGHT ELITE Tissue Oximeter Module compares substantially to the predicates. All have multi-channel capability, an LED light source, similar user interface features on the monitor or host device and the benefits of portability.

Non-Clinical Performance Testing to Demonstrate Substantial Equivalence

The proposed FORE-SIGHT ELITE Tissue Oximeter Module has successfully undergone extensive performance, safety, electromagnetic, software and environmental testing (K180003) to ensure substantial equivalence to the predicate devices. In addition to the above laboratory tests, CAS has conducted a full program of individual hardware, software, and systems verification and validation studies.

Clinical and Phantom Testing to Show Substantial Equivalence

The FORE-SIGHT ELITE Tissue Oximeter Module technology has successfully undergone extensive clinical validation for the indicated use, as demonstrated in the clearance of K180003 and earlier CASMED Premarket Notifications. As documented in the FORE-SIGHT ELITE Clinical Equivalency Report, there is no significant difference between the clinical functionality of this proposed Module and the Module cited in K180003 for oxygen saturation measurements. Clinical validation of changes in hemoglobin concentrations was successfully performed in healthy adult volunteers demonstrating high precision to co-oximetry blood sample references. Longitudinal performance in adult and pediatric cardiac surgical patients and procedures was also evaluated using convenience co-oximetry blood sample references. Additional validation on liquid optical phantoms was performed to demonstrate equivalence of the relative changes in hemoglobin concentrations to the NIRO-200NX reference device cleared under K143219 as well as concurrent frequency domain oximetry measurements.

Refer to Table 1

Conclusions Drawn from Clinical and Non-Clinical Testing

Clinical and phantom evaluation, safety / EMC testing, and software validation demonstrate the FORE-SIGHT ELITE Tissue Oximeter Module is substantially equivalent to the predicate devices.

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PatientPopulation	Sensor	Parameter	CerebralReference	Non-CerebralReference	TypeMeasurement	SubjectWeightRange
Adult	Large	StO2	Co-oximetry of jugular bulb andarterial blood samples¹[Range: 48 to 88%]	Co-oximetry of central venousand arterial blood samples¹[Range: 50 to 90%]	Single Point	≥ 40 kg
		ΔHHb,ΔO₂Hb	Co-oximetry of jugular bulb andarterial blood samples²[Range: ±5 g/dL, ±19 μM]	Co-oximetry of central venousand arterial blood samples²[Range: ±5 g/dL, ±19 μM]	DifferentialChanges
Pediatric -Adolescents,Children,Infants, &Neonates	Medium	StO2	Co-oximetry of internal jugularvein and arterial blood samples[Range: 48 to 92%]	Co-oximetry of central venousand arterial blood samples[Range: 53 to 88%]	Single Point	≥ 3 kg
		ΔHHb,ΔO₂Hb	Co-oximetry of jugular bulb andarterial blood samples³[Range: 0 to 2 g/dL, 7.4 uM]and frequency domain oximeteron liquid optical phantom[Range: ±85 μM]	Co-oximetry of jugular bulband arterial blood samples³[Range: 0 to 2 g/dL, 7.4 uM]and frequency domain oximeteron liquid optical phantom[Range: ±85 μM]	DifferentialChanges
Pediatric -Adolescents,Children,Infants, &Neonates	Small	StO2	Co-oximetry of internal jugularvein and arterial blood samples[Range: 50 to 90%]	Co-oximetry of central venousand arterial blood samples[Range: 66 to 96%]	Single Point	3 to 8 kg
		ΔHHb,ΔO₂Hb	Frequency domain oximeter onliquid optical phantom[Range: ±85 μM]	Frequency domain oximeter onliquid optical phantom[Range: ±85 μM]	DifferentialChanges
Pediatric -Neonates(Term,Premature,Low BirthWeight, VeryLow BirthWeight)	Small	StO2	FORE-SIGHT MC3010⁴[Range: 50 to 90%]	Co-oximetry of umbilical venousand pulse oximetry samples[Range: 66 to 96%]	StO2 dataaveraged in two-minute windows⁵	< 5 kg
		ΔHHb,ΔO₂Hb	Frequency domain oximeter onliquid optical phantom[Range: ±85 μM]	Frequency domain oximeter onliquid optical phantom[Range: ±85 μM]	DifferentialChanges

Table 1: StO2 and Changes in Hemoglobin Concentration Validation Methodology

1 Validations performed on healthy adult volunteers (Age: 19 to 40 years, BMI: 18 to 30.5, Gender: 12 Male and 13 Fementation: 15 Light, 5 Moderate, 5 Dark)

2 Validations performed on healthy volunteer subjects (Age: 19 to 40 years, BMI: 18 to 31.6, Gender: 22 Male and 21 Female, Skin Pigmentation: 21 Light, 14 Moderate, and 8 Dark). Convenience sample measurements evaluated on cardiac surgical patients undergoing cardiopulmonary bypass procedures (Age: 47 to 89 years, BMI: 23.8 to 29.6, Gender: 3 Male and 2 Female, Skin Pight, 1 Moderate).

3 Performance on cardiac surgical patients evaluated using convenients on pediatric patients undergoing interventional catheterization procedures (Age: 0.4 to 9.2 years, BMI: 14.1 to 18.2, Gender: 4 Male and 1 Female, Skin Pigmentation: 2 Light, 1 Moderate, 2 Dark).

Unlike the other FORE-SIGHT ELITE validation studies, this cerebral validation study did not include invasive measurements because of the challenge for medical centers to obtain consent to internal jugular venous catheter in very small subjects.

StO2 data was averaged in two-minute windows for term, premature low birth weight (LBW), and very low birth weight (VLBW) neonates for the following reasons: 1) to reduce the influence of acute changes in body position or touch as the hemodynamics BW and VLBW neonates are not as stable compared to normal birth weight neonates, and 2) to enable measurements for both 3010 and FORE-SIGHT ELITE Sensors or across multiple abdominal locations at nominally the same time for the tes for which only one Sensor can be fitted on the head or specific abdominal location

Regulation Number and Section

§ 870.2700 Oximeter.

(a)
Identification. An oximeter is a device used to transmit radiation at a known wavelength(s) through blood and to measure the blood oxygen saturation based on the amount of reflected or scattered radiation. It may be used alone or in conjunction with a fiberoptic oximeter catheter.(b)
Classification. Class II (performance standards).