The device is a diagnostic imaging system for fixed or mobile installations that combines Positron Emission Tomography (PET) and X-ray Computed Tomography (CT) systems. The CT subsystem produces cross-sectional images of the body by computer reconstruction of x-ray transmission data. The PET subsystem produces images of the distribution of PET radiopharmaceuticals in the patient body (specific radiopharmaceuticals are used for whole body, head, heart and other organ imaging). Attenuation correction is accomplished by either CTAC or Cs-137. The device also provides for list mode, dynamic, and gated acquisitions.

Image processing and display workstations provide software applications to process, analyze, display, quantify and interpret medical images/data. The PET and CT images may be registered and displayed in a "fused" (overlaid in the same spatial orientation) format to provide combined metabolic and anatomical data at different angles. Trained professionals use the images in:

The evaluation, detection and diagnosis of lesions, disease and organ function such as but not limited to cancer, cardiovascular disease, and neurological disorders.
The detection, localization, and staging of tumors and diagnosing cancer patients.
Treatment planning and interventional radiology procedures.

Cardiac imaging software provides functionality for the quantification of cardiology images and datasets including but not limited to myocardial perfusion for the display of wall motion and quantification of left-ventricular function parameters from gated myocardial perfusion studies and for the 3D alignment of coronary artery images from CT coronary angiography onto the myocardium.

Both subsystems (PET and CT) can also be operated independently as fully functional, diagnostic imaging systems including application of the CT scanner as a radiation therapy simulation scanner.

Device Description

The device is a hybrid diagnostic imaging system that combines Positron Emission Tomography (PET) and X-ray Computed Tomography (CT) scanners that can be utilized in fixed installations or mobile environments. The device is comprised of the following system components/subsystems: Positron Emission Tomography (PET), X-ray Computed Tomography (CT), a patient table, gantry separation unit, and the acquisition and processing workstations. The 16-slice configuration is also referred to as Gemini 16 Power.

AI/ML Overview

This document describes the Gemini PET/CT Imaging System and its clearance via a 510(k) premarket notification. The information provided heavily references existing standards and comparisons to predicate devices, rather than a standalone study with explicit acceptance criteria and performance metrics for the device itself as a new, distinct technology with novel AI components.

Based on the provided text, the device is an imaging system (hardware and associated software for display/analysis), not an AI algorithm performing a specific diagnostic task like lesion detection that would typically have quantitative acceptance criteria on metrics like sensitivity/specificity.

Therefore, the requested information, which is focused on AI algorithm performance, cannot be fully extracted from this document in the typical sense.

Here's an attempt to answer the questions based on the available information, noting where specific AI-related metrics or studies are not present:

1. A table of acceptance criteria and the reported device performance

Based on the document, the "acceptance criteria" are compliance with established regulatory and industry standards for medical imaging systems, and "performance" is demonstrated by adherence to these standards and equivalence to predicate devices. There are no specific quantitative acceptance criteria or reported device performance metrics in the sense of accuracy, sensitivity, or specificity for a diagnostic task that an AI algorithm would typically demonstrate.

Acceptance Criteria (based on regulatory and industry standards)	Reported Device Performance
Safety:
- 21 CFR 1020.30/1020.33 Performance Standards for Ionizing	"Philips Medical System adheres to recognized and established industry practice. Radiation safety is assured by compliance and certification to the performance standards for ionizing radiation emitting product, 21CFR 1020.30 and 21CFR 1020.33." Additionally, "Electrical and mechanical safety is assured by adherence and certification to the applicable standards in the IEC 60601-1 series."
Radiation Emitting Products, Computed Tomography Equipment
- IEC 60601-1 series (Electrical and Mechanical Safety)
Imaging Performance:
- NEMA NU-2 standard	"The device performance was measured in accordance with the NEMA-NU2 standard."
Substantial Equivalence:
- Similar intended use to predicate devices	"The device is substantially equivalent to the predicate devices based upon similar intended use, technological comparison, and system performance."
- Similar technological characteristics to predicate devices

2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

The document describes a system performance test measured in accordance with the NEMA-NU2 standard. This standard typically involves phantom studies or specified tests on the physical imaging system itself, not studies on a specific patient data test set for AI algorithm validation. Therefore, information about patient sample size, data provenance, retrospective/prospective nature is not applicable/not provided in this document for the type of evaluation described.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

Since the document describes a system performance test (hardware/physics), not an AI algorithm's diagnostic performance on patient data, there is no mention of experts establishing ground truth for a test set of patient cases.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

Not applicable as there is no patient test set with ground truth established by experts.

5. 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

There is no mention of an MRMC comparative effectiveness study or any study involving human readers with or without AI assistance. The submission is for an imaging system, not an AI diagnostic tool.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

The "device" being described is a combined PET/CT imaging system with associated software for processing, analysis, and display. There is no mention of a standalone AI algorithm (without human-in-the-loop) performance study for a specific diagnostic task. The software components are for image registration, display, quantification of cardiology images, and general image interpretation, presumably by trained professionals.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)

For the system performance tests (NEMA-NU2), ground truth relates to the physical accuracy, resolution, and uniformity measurements of the imaging system, typically using phantoms with known properties. It does not involve expert consensus, pathology, or outcomes data related to patient diagnosis for an AI algorithm.

8. The sample size for the training set

The document describes system performance tests and substantial equivalence to predicate devices. It does not mention a training set for an AI algorithm. The device's software applications (e.g., for cardiac phantom quantification) are likely based on established algorithms and mathematical models, rather than deep learning requiring large training datasets as understood in current AI contexts.

9. How the ground truth for the training set was established

Not applicable, as there is no mention of a training set for an AI algorithm.

Summary

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Image /page/0/Picture/1 description: The image shows a handwritten string of alphanumeric characters. The string appears to be "K041956". The characters are written in a cursive style, with some connections between the letters and numbers. The image has a slightly rough or textured appearance, as if it were scanned from a physical document.

510(k) SUMMARY OF SAFETY AND EFFECTIVENESS

General Information

A.	Submitter/ Contact Person:Philips Medical Systems (Cleveland), Inc.595 Miner Rd.Cleveland, OH 44143
B.	Device Trade Name:	Gemini
	Common Name:	Positron Emission TomographyComputed Tomography X-Ray
	Classification Name:	System, Emission Computed Tomography, (892.1200)System, Computed Tomography X-Ray, (892.1750)
	Device Class:	21CFR 892.1200, Class II21 CFR 892.1750, Class II
	Product Code:	90 KPS and 90 JAK
C.	Date prepared:	June 18, 2004
D.	Predicate Device:	Gemini 16 (K032036)Mx8000 IDT CT System (K012009)Allegro Imaging System (K033782)Discovery LS System (K040172)

E. Performance Standards:

21 CFR 1020.30 1020.33 Performance Standards for Ionizing Radiation . Emitting Products, Computed Tomography Equipment (Applicable Sections)
NEMA NU-2 .

F. Intended Use:

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O The evaluation, detection and diagnosis of lesions, disease and organ function such as but not limited to cancer, cardiovascular disease, and neurological disorders.
o The detection, localization, and staging of tumors and diagnosing cancer patients.
O Treatment planning and interventional radiology procedures.

Both subsystems (PET and CT) can also be operated independently as fully functional, diagnostic imaging systems including application of the CT scanner as a radiation therapy simulation scanner.

ு. Device Description/ Comparison with Predicate Device:

H. System Performance Test/ Summary of Studies:

To minimize electrical, mechanical and radiation hazards. Philips Medical System adheres to recognized and established industry practice. Radiation safety is assured by compliance and certification to the performance standards for ionizing radiation emitting product, 21CFR 1020.30 and 21CFR 1020.33. The radiation safety product report will be filed in accordance with 21CFR 1002.10 with the Center for Device and Radiological Health. Electrical and mechanical safety is assured by adherence and certification to the applicable standards in the IEC 60601-1 series. The device performance was measured in accordance with the NEMA-NU2 standard.

I. Comparison to Predicate Devices:

The device is a modification of the currently marketed Gemini 16 PET/CT System (K032036). Design modifications include the addition of third party cardiac display and analysis software, enhancements to DICOM workflow and Syntegra. The similarities and differences between the Gemini and the predicate devices are described in detail in Section VI of the premarket notification.

In conclusion, the device is substantially equivalent to the predicate devices based upon similar intended use, technological comparison, and system performance.

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Image /page/2/Picture/1 description: The image shows the seal of the Department of Health & Human Services USA. The seal is circular, with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" arranged around the top half of the circle. The bottom half of the circle contains a stylized image of an eagle.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

JUL 2 9 2004

Philips Medical Systems (Cleveland), Inc. Re: K041955 % Mr. Morten Simon Christensen Reviewer Underwriters Laboratories, Inc 1655 Scott Boulevard SANTA CLARA CA 95050-4169

Trade/Device Name: Gemini PET/CT Imaging System Regulation Number: 21 CFR 892.1200 Regulation Name: Emission computed tomography system Regulation Number: 21 CFR 892.1750 Regulation Name: Computed tomography x-ray system Regulatory Class: II Product Code: 90 KPS and JAK Dated: July 19, 2004 Received: July 21, 2004

Dear Mr. Christensen:

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.

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

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results 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 contact the Office of Compliance at one of the following numbers, based on the regulation number at the top of the letter:

8xx. Ixxx	(301) 594-4591
876.2xxx, 3xxx, 4xxx, 5xxx	(301) 594-4616
884.2xxx, 3xxx, 4xxx, 5xxx, 6xxx	(301) 594-4616
892.2xxx, 3xxx, 4xxx, 5xxx	(301) 594-4654
Other	(301) 594-4692

Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97) you may obtain. Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers, 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,

Nancy C. Brydon

Nancy C. Brogdon Director, Division of Reproductive, Abdominal and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known): Not Known): Not Known K 0 4 / 9 5 5

Device Name: Gemini

Indications for Use.

The device is a diagnostic imaging system for fixed or mobile installations that combines Positron Emission Tomography (PET) and X-ray Computed Tomography (CT) systems. The CT subsystem produces crosssectional images of the body by computer reconstruction of x-ray transmission data. The PET subsystem produces images of the distribution of PET radiopharmaceuticals in the patient body (specific radiophamaceuticals are used for whole body, head, heart and other organ imaging). Attenuation correction is accomplished by either CTAC or Cs-137. The device also provides for list mode, dynamic, and gated acquisitions.

Image processing and display workstations provide software applications to process, analyze, display, quantify and interpret medical images/data. The PET and CT images may be registered and displayed in a fitused (overlaid in the same spatial orientation) format to provide combined metabolic and anatomical data at different angles. Trained professionals use the images in:

The evaluation, detection and diagnosis of lesions, disease and organ function such as but not limited to ಂ cancer, cardiovascular disease, and neurological disorders.
The detection, localization, and staging of tumors and diagnosing cancer patients. o
Treatment planning and interventional radiology procedures. ಂ

Cardian imaging software provides functionality for the quantification of cardiology images and datasets including but not limited to myocardial perfusion for the display of wall notion and quantification of left ventricular from gated myocardial perfusion studies and for the 3D alignment of or left artery images from CT coronary angiography onto the myocardium.

Both subsystems (PET and CT) can also be operated independently as fully functional, diagnostic imaging systems including application of the CT scanner as a radiation therapy similation scanner.

Prescription Use ✓ (Part 21 CFR 801 Subpart D)

AND/OR

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

(Please do not WRITE BELOW THIS LINE-CONTINUE on another Page of needed)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Aaroul Sroydon

(Division Sign-Off)
Division of Reproductive, Abdominal,
and Radiological Devices
510(k) Number K041955

Page of

Regulation Number and Section

§ 892.1200 Emission computed tomography system.

(a)
Identification. An emission computed tomography system is a device intended to detect the location and distribution of gamma ray- and positron-emitting radionuclides in the body and produce cross-sectional images through computer reconstruction of the data. This generic type of device may include signal analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component parts, and accessories.(b)
Classification. Class II.