The non-invasive Adult Cerebral Oximeter Model 2040 should be used as an adjunct monitor of regional hemoglobin oxygen saturation of blood in the brain of an adult. The Cerebral Oximeter Monitor System should not be used as the sole basis for decisions as to the diagnosis or therapy. The value of data from the Cerebral Oximeter Monitoring System has not been demonstrated in disease states.

Device Description

The Adult Cerebral Oximeter, model 2040 measures brain oxygenation allowing the clinician to accurately determine absolute levels of tissue and venous oxygenation in the brain. This measurement can be of significant value in numerous acute care (OR, ICU, ER) situations, providing health care professionals with information to guard against neurological injuries due to compromised brain oxygenation, which can occur during many surgical and clinical situations. The 2040 Cerebral Oximeter consists of an optical transducer containing a laser light source and photodiode detectors, and a graphic display monitor with user interface. The non-invasive, reflection mode, optical transducer is placed on the forehead of the subject via a disposable probe attachment to determine cerebral oxygenation. The 2040 Cerebral Oximeter will be safe to use, since it is designed to operate as a Class I laser product, the safest FDA laser classification. Additional safety features include a laser interlock system designed to prevent laser operation in case the optical transducer is not securely attached to the subject. A patent-protected algorithm optimizes accuracy of the device in measurements of absolute brain tissue oxygen saturation and, in conjunction with pulse oximetry, in providing absolute readings of brain venous oxygen saturation.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study information for the CAS Medical Systems, Inc. Adult Cerebral Oximeter Monitor (Model 2040) based on the provided text:

Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state formal "acceptance criteria" but rather reports the device's performance metrics (bias and precision) in comparison to a reference standard derived from co-oximetry. We can infer that the reported values met the internal performance specifications that CAS Medical Systems deemed acceptable for substantial equivalence.

Performance Metric	Acceptance Criteria (Implied)	Reported Device Performance
Bias (Model 2040 StO2 vs. Reference StO2)	(Not explicitly stated)	0.43
Precision (Model 2040 StO2 vs. Reference StO2)	(Not explicitly stated)	± 3.78 (1 standard deviation)
Bias (Model 2040 SvO2 vs. Reference SjbO2)	(Not explicitly stated)	0.63
Precision (Model 2040 SvO2 vs. Reference SjbO2)	(Not explicitly stated)	± 5.38 (1 standard deviation)

Study Information

Sample Size used for the Test Set and Data Provenance:
- Sample Size: Not explicitly stated, but the study involved "healthy adult volunteers."
- Data Provenance: Prospective clinical study conducted at Duke University Medical Center in Durham, North Carolina, USA.
Number of Experts used to establish the ground truth for the test set and the qualifications of those experts:
- The ground truth was established through direct physiological measurements (blood samples analyzed by co-oximetry), not by expert interpretation. Therefore, the concept of "experts establishing ground truth" in the interpretive sense does not apply here. The expertise lies in the medical professionals performing the procedures (e.g., placing catheters, drawing blood) and the laboratory personnel operating the co-oximeter.
Adjudication method for the test set:
- Not applicable. The ground truth was based on objective physiological measurements from blood samples, not subjective interpretations requiring adjudication.
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. This was a standalone performance study of the device against a reference standard, not a comparative effectiveness study involving human readers or AI assistance.
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Yes, this was a standalone performance study. The device's algorithm, which calculates cerebral oxygenation values, was directly compared to the reference standard. There was no human-in-the-loop component in the performance evaluation described.
The type of ground truth used:
- Outcomes Data/Physiological Measurement: The ground truth was established using co-oximetry analysis of arterial (SaO2) and jugular bulb (SjbO2) blood samples, considered a direct physiological measurement of oxygen saturation in the bloodstream. These values were then used to calculate a "Reference StO2%" and "Reference SjbO2."
The sample size for the training set:
- Not explicitly stated. The document describes the clinical testing for showing substantial equivalence, which appears to be a validation/test set for the already developed device. It does not provide details about a separate training set used during the algorithm development phase.
How the ground truth for the training set was established:
- Not explicitly stated, as details regarding a distinct training set are absent. However, it can be inferred that similar physiological measurement methods (blood sampling, co-oximetry) would likely have been used during the development and initial calibration of the proprietary algorithm if a separate training set was utilized.

Summary

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K051257

Image /page/0/Picture/1 description: The image shows the logo for CAS Medical Systems, Inc. The logo includes the company name in bold, uppercase letters, with the tagline "TECHNOLOGY APPLIED TO MEDICINE" underneath. The address "44 EAST INDUSTRIAL ROAD, BRANFORD, CONNECTICUT 06405" is printed below the tagline.

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203-488-6056 (FAX) 203-488-9438

DEC 2 2 2005

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) 488-6056 Fax - (203) 488-9438Email – rjeffrey@casmed.com
Prepared:	May 9, 2005
Trade Name:	Adult Cerebral Oximeter Monitor
Common Name:	Model 2040 Monitor
Classification Name:	Cerebral Oximeter (870.2700)

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Kosis2

EQUIVALENCE (Predicate Device)

Rise 2 f3

The Adult Cerebral Oximeter Monitor, Model 2040 is equivalent to the following devices:

Somanetics Invos® 5100 / 3100A Cerebral Oximeter (K001842 / K960614);
Spectros T-Stat™ 303 Microvascular Tissue Oximeter (K040684); な
- Hitachi Medical ETG-4000 / 1000 Optical Topography System (K042501 / 011320).

DESCRIPTION

The 2040 Cerebral Oximeter consists of an optical transducer containing a laser light source and photodiode detectors, and a graphic display monitor with user interface. The non-invasive, reflection mode, optical transducer is placed on the forehead of the subject via a disposable probe attachment to determine cerebral oxygenation. The 2040 Cerebral Oximeter will be safe to use, since it is designed to operate as a Class I laser product, the safest FDA laser classification. Additional safety features include a laser interlock system designed to prevent laser operation in case the optical transducer is not securely attached to the subject. A patent-protected algorithm optimizes accuracy of the device in measurements of absolute brain tissue oxygen saturation and, in conjunction with pulse oximetry, in providing absolute readings of brain venous oxygen saturation ..

Adult Cerebral Oximeter Intended Use

Device Technological Characteristics Comparing Device to Predicates

The Adult Cerebral Oximeter, Model 2040 compares substantially to one or more of the predicates cited in that they use fundamentally the same optical operating principle, called diffuse reflectance spectroscopy. All monitors use light to probe a cross-section of the microvasculature of tissue (mixed bed of arterioles, capillaries and venuoles). The 2040 and predicates analyze light returning from tissue, after having passed through tissues, for hemoglobin in its oxygenated and dcoxygenated forms in the optically sampled region. All calculate tissue oxygen saturation (%St02), a value reflecting percentage of oxygenated hemoglobin in the sampled mircovasculature of tissue.

Nonclinical Performance Testing to Show Substantial Equivalence

The Adult Cerebral Oximeter, Model 2040 will be tested in accordance with the following standards as per CAS Product Performance Specifications prior to release to market. The following non-clinical tests will be performed:

Image /page/1/Picture/16 description: The image is a black and white photograph. The left side of the image is mostly black, while the right side of the image is a mix of black and white. The black and white mix on the right side of the image appears to be some kind of texture. The image is mostly dark, with some light areas on the right side.

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UL60601-1 (w/ CSA 22.2 No. 60601-1) Safety testing for use of the UL Classified mark;
IEC60601-1 Safety of Medical Electrical Equipment; .
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EN60601-1-2: 2001 Safety of Medical Electrical Equipment with regard to EMC Emissions . and EMC Immunity;
EN 865 Pulse Oximeters (CAS VP/VR 050022) Particular Requirements (as applicable); .
Testing specified in the Reviewer Guidance for Premarket Notification Submissions (CAS . 21-07-0076)
VP/VR 050012 System Validation Plan .
VP/VR 050013 System IPX1 Verification Plan
VP/VR 050014 Hardware Verification Plan .

Clinical Testing to Show Substantial Equivalence

Clinical data on adult subjects was collected at the Duke University Medical Center in Durham, North Carolina. In this study, healthy adult volunteers were subjects for comparison using an internal jugular bulb catheter on the subject's right side and a radial arterial line on the left. Two sensors from the cerebral oximeter model 2040 were placed on the patient's forehead, on the right and left sides respectively. Hypoxic mixtures of gas were delivered and data was collected a different periods of ascending and descending concentrations in 5 minute intervals. At set points, blood samples were drawn simultaneously from the jugular bulb and the radial arterial catheters and analysis for oxygen tension was performed using a co-oximeter. The patient was monitored and protocol stopped if Sp02 values from a pulse oximeter reached <70%.

Conclusions Drawn from Clinical and Nonclinical Testing

The model 2040 St02 showed a strong correlation with the reference St02 over the spectrum of Sp02 values between 70 and 100%. The bias and precision (1 standard deviation) for the model 2040 St02 compared to reference St02 derived from co-oximetry of arterial (Sa02) and jugular bulb (Sjb02) blood samples was 0.43 ± 3.78, based on the following expression:

Reference St02% = Sa02 x 0.3 + Sjb02 x 0.7

The cerebral oximeter St02 value represents oxygen saturation in the brain tissue microvasculature containing venous and arterial blood volume at a ratio of 70:30. The model 2040 Sv02 showed a strong correlation with the reference SjbO2 over the spectrum of Sp02 values between 70 and 100%. The bias and precision for the model 2040 Sv02 compared to reference Sjb02, derived from cooximetry of the jugular bulb blood samples was 0.63 ± 5.38. Sv02 was determined from the following expression:

Sv02 = (St02 - Sp02 x 0.3) / 0.7

In the above expression, Sp02 is arterial oxygen saturation from a pulse oximeter and St02 is determined by the cerebral oximeter.

Image /page/2/Picture/16 description: The image is a black and white photograph that appears to be a close-up of a dark, solid object. The object is rectangular in shape and takes up most of the frame. The left side of the object is a solid black, while the right side has a grainy texture that fades into white. The overall impression is one of darkness and contrast, with the solid black area dominating the image.

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Image /page/3/Picture/1 description: The image shows the logo for the U.S. Department of Health and Human Services. The logo features a stylized caduceus symbol, which is a staff with two snakes coiled around it. The words "DEPARTMENT OF HEALTH AND HUMAN SERVICES, USA" are arranged in a circular pattern around the caduceus symbol.

Public Health Service

DEC 2 2 2005

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

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

Re: K051257

Trade/Device Name: Adult Cerebral Oximeter Monitor Regulation Number: 21 CFR 870.2700 Regulation Name: Oximeter Regulatory Class: II Product Code: DQA Dated: December 2, 2005 Received: December 5, 2005

Dear Mr. Jeffrey:

We have reviewed your Section 510(k) premarket notification of intent to market the device we have reviewed your Section 9 ro(x) premaine is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate for use stated in the encrosule) to regally manatise provide Americal Device American be of Development commerce prior to May 26, 1776, the enactinent with the provisions of the Federal Food, Drug, devices that have been recuire approval of a premarket approval application (PMA). and Cosment Act (Act) that do not require subject to the general controls provisions of the Act. The You may, therefore, market the device, seeject to the of
general controls provisions of the Act include requirements for annual registration, listing of general controls provisions of the tice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), If your device is classified (600 acon controls. Existing major regulations affecting your device it may be subject to such additional vontrols. Title 21, Parts 800 to 898. In addition, FDA can be found in the Ood of Features concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean Please be advised that i Dri 3 issuates of a occession of the requirements of the Act that TDA has made a decemmation that your is a your is the Federal agencies. You must or any rederal statutes and regulations and adding, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set CTN in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the elcotronic forth in the quality byovens (Sections 531-542 of the Act); 21 CFR 1000-1050.

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This letter will allow you to begin marketing your device as described in your Section 510(k) I mis letter will anow you to begin maneting of substantial equivalence of your device to a legally premarket notification: "The PDF in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please IT you desire specific advice ion your as (240) 276-0115. Also, please note the regulation entitled, Collider the Office of Compulation (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small other general international and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html.

Sincerely yours,

Barbara Brehm

Mark Melkerson Acting Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Indications for Use

Adult Cerebral Oximeter, Model 2040

05/257

510(k) Number (if known):

Device Name:

Indications for Use:

The non-invasive Adult Cerebral Oximeter Model 2040 should The non-invasive Adult Sonitor of regional hemoglobin oxygen be used as an adjunts monin of an adult. The Cerebral Oximeter Monitor System should not be used as the sole Oximeler Monitor Oyoton is or the diagnosis or therapy. The value basis for decisions as to the critical oximeter Monitoring System has not been demonstrated in disease states.

Prescription Use (Part 21 CFR 801 Subpart D)

AND/OR

Over-the-Counter Use_ (21 CFR 807 Subpart C)

(Please do not write below this line – continue on another page if needed)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Xaubaro BneuuD

510(k) I

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Division of General, Restorative, and Neurological Devices

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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).