K Number
K172080
Manufacturer
Date Cleared
2017-09-29

(81 days)

Product Code
Regulation Number
892.5900
Panel
RA
Reference & Predicate Devices
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

The Xstrahl Photoelectric Therapy System is a low energy X-Ray system intended for superficial radiotherapy and surface electronic brachytherapy treatment of primary malignant epithelial neoplasms of the skin and keloids.

Typical applications include treatment for Basal Cell Carcinoma, Squamous Cell Carcinoma, Metatypic Carcinoma, Cutaneous Appendage Carcinoma, Karposi's Sarcoma, Merkel Cell Carcinoma, Lentigo Maligna, Lentigo Maligna Melanoma, Cutaneous Lymphomas (B and T cell) and Keloids.

Device Description

The Photoelectric Therapy System is a compact and ergonomic superficial X-Ray therapy system operating in the 10kV to 80kV range intended for superficial radiotherapy and surface electronic brachytherapy treatment of primary malignant epithelial neoplasms of the skin and keloids.

The Photoelectric Therapy System is a standalone X-Ray radiation therapy system consisting of the X-Ray Therapy Unit, a TP2 Central Control Unit (CCU), a Control POD (Control POD), and a PC on which user interface software is loaded. The system has a time based control system used with treatment filters and applicators. A range of bespoke treatment applicators and beam filters are available for use with the Photoelectric Therapy System.

The system is freestanding, self-contained, unobtrusive, compact and ergonomic in design, which helps to ensure a reassuring and stress-free patient experience. The system is floor mounted in order to accommodate almost any clinical space, and features ergonomically designed controls ensuring smooth adjustment and safe, simple patient set-up. The system requires connection to the clinical facilities electrical supply and room interlocks.

AI/ML Overview

This document describes a 510(k) premarket notification for the Xstrahl Photoelectric Therapy System, an X-ray radiation therapy system. The notification primarily focuses on demonstrating substantial equivalence to a predicate device (Sensus Healthcare SRT-100 Superficial Radiation Therapy System) through non-clinical testing.

Here's an analysis of the provided information regarding acceptance criteria and supporting studies:

1. Table of Acceptance Criteria and Reported Device Performance:

The document does not explicitly provide a table of acceptance criteria with corresponding device performance for a clinical evaluation. Instead, it details adherence to various international and national standards for electrical safety, electromagnetic compatibility, usability, and dosimetry for an X-ray therapy system. The "reported device performance" in this context refers to compliance with these standards, not necessarily clinical efficacy.

Acceptance Criteria CategorySpecific Standard/ProtocolReported Device Performance
Electrical SafetyIEC 60601-1: General requirements for basic safety and essential performanceVerified compliance through non-clinical tests
UsabilityIEC 60601-1-6: Collateral standard. UsabilityVerified compliance through non-clinical tests
IEC 62366: Application of usability engineering to medical devicesVerified compliance through non-clinical tests
X-ray Therapy Specific Safety & PerformanceEN 60601-2-8 (IEC-60601-2-8): Particular requirements for the basic safety and essential performance of therapeutic X-ray equipment operating in the range 10 kV to 1 MVVerified compliance through non-clinical tests
Electromagnetic Compatibility (EMC)EN 60601-1-2 (IEC 60601-1-2): General requirements for safety - Collateral standard: Electromagnetic compatibility requirements and testsVerified compliance through non-clinical tests
Dosimetry VerificationIPEMB Code of Practice Phys. Med. Biol. 41 (1996) 2605–2625Verified compliance through independent measurements at NPL UK
AAPM Task Group 61 (TG-61) ProtocolVerified compliance through independent measurements at NPL UK
Manufacturing/Quality ControlXstrahl Customer Acceptance Test (CAT) procedureVerified compliance through independent measurements at NPL UK

2. Sample Size Used for the Test Set and Data Provenance:

The document describes non-clinical testing for safety, EMC, usability, and dosimetry. Therefore, there is no "test set" of patient data in the context of a clinical study. The "test set" would refer to the physical device prototypes and components subjected to these engineering and physics tests. The data provenance is from non-clinical laboratory settings in the UK (Xstrahl Ltd. and National Physics Laboratory UK). The data is prospective in the sense that the device was specifically manufactured and tested against these standards.

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

Since this document focuses on non-clinical engineering and physics tests, the concept of "ground truth for a test set" established by medical experts (like radiologists) does not apply in the typical sense of a clinical trial.

However, the National Physics Laboratory UK (NPL) is a recognized authority in measurement science, and their involvement in dosimetry verification suggests that their experts (likely medical physicists or similar specialists) were used. The IPEMB Code of Practice and AAPM Task Group 61 Protocol are established by expert bodies in medical physics, and adherence to these protocols reflects an expert consensus on accurate dosimetry.

The "experts" involved in establishing the "ground truth" for these technical tests would be:

  • Engineers and physicists at Xstrahl Ltd. involved in the design, development, and internal testing of the device.
  • Independent medical physicists/scientists at the National Physics Laboratory UK (NPL) who performed the verification measurements according to recognized professional codes of practice. Their qualifications would typically include advanced degrees in physics, medical physics, or related fields, with expertise in radiation dosimetry and medical device testing.

4. Adjudication Method for the Test Set:

Not applicable in the context of non-clinical engineering and physics testing. Adjudication methods like "2+1" are typically used in clinical studies involving multiple human readers to resolve discrepancies in diagnoses or interpretations. The non-clinical tests described involve objective measurements and compliance verification against predefined technical standards.

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:

No. The document does not describe any MRMC comparative effectiveness study, nor does it mention AI or human-in-the-loop performance. This device is an X-ray radiation therapy system, not an imaging or diagnostic AI-powered device.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:

No. This question is also not applicable. The device is a physical X-ray therapy system. There is no "algorithm only" performance reported in the context of AI or diagnostic interpretation. The "system" operates as a standalone piece of equipment for delivering radiation therapy as intended.

7. The Type of Ground Truth Used:

For the non-clinical tests, the "ground truth" is defined by:

  • Established international and national standards: IEC 60601 series, EN 60601 series, IEC 62366. Compliance with these standards is the "truth" being verified for safety, EMC, and usability.
  • Recognized codes of practice for dosimetry: IPEMB Code of Practice and AAPM Task Group 61 Protocol. The physical measurements conducted by NPL are compared against the expected values as defined by these protocols to establish the "ground truth" for radiation output accuracy.
  • Manufacturer's own Customer Acceptance Test (CAT) procedure: This internal standard serves as a ground truth for the device's specific manufactured performance characteristics.

8. The Sample Size for the Training Set:

Not applicable. The document describes a medical device, not an AI or machine learning model. Therefore, there is no "training set" in this context.

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

Not applicable. As there is no training set for an AI model, the question of establishing its ground truth is irrelevant to this submission.

§ 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.