The Photon Radiosurgery System (PRS) is a complete system for highly focused treatment of intracranial tumors. The PRS includes an X-ray Source and Control Box, along with accessories for clinical treatment, quality assurance, laboratory calibration and dose verification. The miniature X-ray source incorporates a 3.175 mm diameter. 10 cm long interstitial probe and is designed to be mounted on a stereotactic frame so that the probe tip, covered with a sterile sheath, can be positioned precisely into the tumor. High dose rate, low energy X-rays are emitted from the probe tip in a spherical pattern and a prescribed therapeutic radiation dose delivered in a single fraction destroys the tumor from the inside out. Voltage, beam current, and treatment time or photon count are set on the Control Box which is powered by a rechargeable battery. Accessories are provided to assist in placement of the interstitial probe and to perform quality control of the X-ray source in the clinical setting. Additional laboratory-based components of the PRS include an automated dosimetry water tank for calibration and a CCD-camera based radiochromic film reader for dose verification.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study information for the Photoelectron Corporation PHOTON RADIOSURGERY SYSTEM (K964947), based on the provided text:

Acceptance Criteria and Reported Device Performance

The provided 510(k) summary does not explicitly list quantitative acceptance criteria in a table format with corresponding reported performance metrics. Instead, it focuses on demonstrating substantial equivalence to predicate devices in terms of intended use, technological/functional features, construction, materials, safety, and effectiveness.

The "acceptance criteria" can be inferred from the claims made regarding the device's performance and similarity to predicate devices, particularly that it is "as safe and effective as legally marketed predicate devices for the irradiation of intracranial tumors."

Here's an attempt to structure the information based on the available text:

Acceptance Criteria (Inferred)	Reported Device Performance
Safety:
Emit high-dose rate, low-energy X-ray radiation.	Emits high dose rate, low energy X-ray radiation in a spherical pattern from the tip of an X-ray Source probe.
Be able to be placed inside the body.	Probe can be placed inside the body.
Create highly demarcated areas of tissue destruction in targeted animal tissue without evidence of deleterious effects.	Demonstrated in preclinical animal studies to create highly demarcated areas of tissue destruction in targeted animal tissue without evidence of deleterious effects.
Compliance with electromagnetic compatibility.	Preclinical tests included testing for compliance with electromagnetic compatibility.
Materials biocompatibility.	Preclinical tests included testing for materials biocompatibility.
Demonstrate safety in human subjects.	Two phases of clinical studies conducted over four years at multiple sites, assessing safety through clinical, radiological, functional, and quality of life measures, and autopsy data. Concluded to be safe.
Minimal collateral radiation protection concerns compared to predicate devices.	Discussion of collateral radiation protection against predicate devices.
Effectiveness:
Irradiate and destroy intracranial tumors in a precise and controllable manner.	Targeted tumors can be irradiated and destroyed in a precise and controllable manner.
Achieve therapeutic radiation dose in a single fraction.	Prescribed therapeutic radiation dose delivered in a single fraction.
Be comparable to predicate devices in radiation sources, methods of application, relative dose rates, and dose adjustment methods.	Technological and functional characteristics are similar to interstitial brachytherapy and external beam stereotactic radiosurgery systems (LINAC and/or Gamma Knife) in these aspects.
Demonstrate effectiveness in human subjects for irradiation of intracranial tumors.	Two phases of clinical studies conducted over four years at multiple sites, assessing effectiveness through clinical, radiological, functional, and quality of life measures, and autopsy data. Concluded to be effective.

Detailed Study Information:

Sample size used for the test set and the data provenance:
- Sample Size (Clinical Test Set): "eligible subjects diagnosed with primary or metastatic intracranial tumors which were either solitary or multiple in number." No specific number is provided in the summary, but it implies a cohort of human patients.
- Data Provenance: "at multiple clinical sites" (implies prospective human clinical data). "Autopsy data was also obtained" (retrospective on deceased subjects).
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- The document does not specify the number of experts or their qualifications for establishing ground truth in the clinical studies. It mentions "clinical, radiological, functional and quality of life measures," which would typically involve expert interpretation (e.g., radiologists for imaging, neurologists for functional assessments, etc.), but this is not detailed.
Adjudication method for the test set:
- The document does not specify an adjudication method (e.g., 2+1, 3+1, none) for the clinical test set data.
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, an MRMC study was not done. This device is an X-ray radiation therapy system, not an AI-powered diagnostic imaging tool. Therefore, the concept of "human readers improve with AI vs without AI assistance" does not apply.
If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Yes, a standalone performance was done in the sense of the device performing its intended function without direct human "in-the-loop" assistance for radiation delivery. The device delivers radiation based on pre-programmed parameters. Preclinical in vitro laboratory studies and animal studies would represent standalone performance of the system against biological tissues.
The type of ground truth used:
- Preclinical: "Highly demarcated areas of tissue destruction" observed in animal studies.
- Clinical: "Autopsy data" (direct objective evidence of tissue effects), "clinical, radiological, functional and quality of life measures." This implies a combination of direct pathological evidence and various clinical/imaging outcomes.
The sample size for the training set:
- The document does not specify a separate "training set" sample size. The description of clinical studies refers to the overall evaluation of safety and effectiveness, implying a single study phase for reporting to the FDA rather than a distinct training/test split in the modern machine learning sense. The device itself is not described as an AI/ML algorithm that requires a "training set" in that context.
How the ground truth for the training set was established:
- As there's no mention of a "training set" in the context of an AI/ML device, this question is not directly applicable. For the overall studies, ground truth was established through a combination of animal tissue analysis, human autopsy data, and various clinical and radiological assessments as outlined above.

Summary

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K964947

JUN 20 1997

510(k) Summary for Photoelectron Corporation PHOTON RADIOSURGERY SYSTEM

Date Prepared: 1.

December 9, 1996

Submitter's Name and Address: 2.
Photoelectron Corporation 5 Forbes Road Lexington, MA 02173 USA

Contact Person: Thomas R. Varricchione, MBA, RRT Director. Clinical Research & Regulatory Affairs Photoelectron Corporation

Telephone: (617) 861-2069 Facsimile: (617) 259-0482

Proprietary Name: Photon Radiosurgery System Device Name: র্ব Miniature X-ray Source with Control and Common Name: Calibration Systems and Accessories Classification Name: X-ray Radiation Therapy System

5. Predicate Device:

The Photon Radiosurgery System is substantially equivalent to the Nucletron-Oldeft microSelectron-HDR interstitial brachytherapy device and the Elekta Radiosurgery Inc. Leksell Gamma Unit Model 23004.

Device Description: 6.

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positioned precisely into the tumor. High dose rate, low energy X-rays are emitted from the probe tip in a spherical pattern and a prescribed therapeutic radiation dose delivered in a single fraction destroys the tumor from the inside out. Voltage, beam current, and treatment time or photon count are set on the Control Box which is powered by a rechargeable battery. Accessories are provided to assist in placement of the interstitial probe and to perform quality control of the X-ray source in the clinical setting. Additional laboratory-based components of the PRS include an automated dosimetry water tank for calibration and a CCD-camera based radiochromic film reader for dose verification.

Intended Use: 7.

The intended use of the Photon Radiosurgery System is to irracranial tumors.

Comparison of Technological Characteristics: 8.

Technological and functional characteristics of the PRS are similar to those of interstitial brachytherapy systems with radionuclides and to external beam stereotactic radiosurgery systems (LINAC and/or Gamma Knife). Comparison of the PRS with these devices included radiation sources, methods of application, relative dose rates, dose adjustment methods, collateral radiation protection, and the exposure of healthy This discussion illustrated the PRS's similarities with tissue to radiation. technological and functional features of the predicate devices.

9. Preclinical Tests:

Several preclinical in vitro laboratory studies were conducted to characterize performance of the PRS, especially with regard to its output parameters and their Preclinical tests also included animal studies in rats and dogs which effects. characterized the effects of in vitro PRS irradiation of liver and brain tissue. In vitro and in vivo studies were also conducted to characterize the thermal properties of the PRS X-ray source. These studies demonstrated that the PRS was able to create highly demarcated areas of tissue destruction in targeted animal tissue without evidence of deleterious effects. Preclinical tests conducted on the PRS also included testing for compliance with electromagnetic compatibility and materials biocompatibility requirements.

12/9/96

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10. Clinical Tests:

Two phases of clinical studies to evaluate the safety and effectiveness of the Photon Radiosurgery System (PRS) for irradiation of intracranial tumors were conducted over a four year period at multiple clinical sites. Studies included treatment of eligible subjects diagnosed with primary or metastatic intracranial tumors which were either solitary or multiple in number. Assessment methods used to evaluate safety and effectiveness included clinical, radiological, functional and quality of life measures. Autopsy data was also obtained and provided to FDA as direct, objective evidence of the effects of PRS irradiation in comparison with the effects of other radiation therapy devices. A summary and analysis, as well as complete patient data. were provided to FDA as evidence of the safety and effectiveness of the PRS for treatment of intracranial tumors.

11. Conclusions:

Studies performed with the Photon Radiosurgery System (PRS) demonstrate that it emits high dose rate, low energy X-ray radiation in a spherical pattern from the tip of an X-ray Source probe which can be placed inside the body. Targeted turnors can be irradiated and destroyed in a precise and controllable manner. Data provided in this 510(k) Premarket Notification demonstrates that the Photon Radiosurgery System has the same intended use, has similar technological and functional features, employs similar construction methods and materials, and is as safe and effective as legally marketed predicate devices for the irradiation of intracranial tumors.

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Image /page/3/Picture/0 description: The image shows the logo for the Department of Health & Human Services USA. The logo consists of a circular border with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" written around it. Inside the circle is a stylized emblem featuring three abstract human profiles facing to the right, stacked on top of each other.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

JUN 20 1997

Thomas R. Varricchione, MBA, RRT Director, Clinical Research and Regulatory Affairs PeC Photoelectron Corporation 5 Forbes Road Lexington, MA 02173

Re: K964947

Photon Radiosurgery System (PRS) Dated: April 8, 1996 Received: April 9, 1997 Regulatory class: II 21 CFR 892.5900/Procode: 90 JAD

Dear Mr. Varrichione:

We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have decemined the device is substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). 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 (Premarket Approval), 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 895. A substantially equivaliation assumes compliance with the Good Manufacturing Practice for Medical Devices: General (GMP) regulation (21 CFR Part 820) and that, through periodic GMP inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations,

This letter will allow you to begin marketing your device as described in your 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 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4591 for Radiology devices, Nose and Throat devices. 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" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address "http://www.fda.gov/cdrh/dsmamain.html".

Sincerely yours,

William Yi

Lillian Yin, Ph.D. Director, Division of Reproductive, Abdominal, Ear, Nose and Throat, and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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510(k) Number (if Known):_K964947

Device Name: Photon Radiosurgery System

Indications For Use:

The Photon Radiosurgery System is intended to be used for the irradiation of intracranial tumors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NECESSARY)

Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
Division of Reproductive, Abdominal, ENT,
and Radiological Devices

510(k) Number K964947

Prescription Use V (Per 21 CFR 801.109)

Photoelectron Corporation Photon Radiosurgery System 510(k)

Page vii

Over-The-Counter Use _________________________________________________________________________________________________________________________________________________________

Regulation Number and Section

§ 892.5900 X-ray radiation therapy system.

(a)
Identification. An x-ray radiation therapy system is a device intended to produce and control x-rays used for radiation therapy. This generic type of device may include signal analysis and display equipment, patient and equipment supports, treatment planning computer programs, component parts, and accessories.(b)
Classification. Class II.