(246 days)
The BEAMSCAN MR system is used preferably in combined MRI-radiation therapy systems with static magnetic fields of up to 1.5T and is intended to collect beam data in water under the aspect of machine QA for the following purposes:
- acceptance testing and/or commissioning of a combined MRI-radiation therapy system
- measurements after repair or replacement of major treatment unit components of a combined MRI-Radiation therapy system
- beam data analysis according to international therapy dosimetry protocols
- acquisition, formatting and transfer of basic data to treatment planning systems
- periodic QA procedures, e.g. constancy check
- high precision data acquisition for scientific research (not a medical device indication)
The BEAMSCAN MR system is comprised of a PMMA tank with a moving mechanism and radiation detectors. Further main components are a carriage with built-in electrometer, control unit and control interface. The carriage includes a water reservoir. The whole system is controlled by software for data display and processing.
Here's a breakdown of the acceptance criteria and the study information for the BEAMSCAN MR device, based on the provided FDA 510(k) summary:
The document focuses on demonstrating substantial equivalence to a predicate device (BEAMSCAN water phantom system, K161807) and adapting the system for use in combined MRI-radiation therapy systems with static magnetic fields up to 1.5T. Therefore, the "acceptance criteria" largely revolve around meeting relevant safety and performance standards for this new environment, and the "study" involves verification and validation testing to confirm these aspects.
1. A table of acceptance criteria and the reported device performance
| Acceptance Criteria Category | Specific Criteria/Standard | Reported Device Performance |
|---|---|---|
| Electrical Safety | IEC 61010-1:2010 (focus on user safety) | Certified as compliant with IEC 61010-1:2010. |
| EMC (Emission & Immunity) | IEC 60601-1-2:2014 (emission and immunity) according to IEC/CISPR 11:2009 (modified + A1:2010) | Certified as compliant with IEC 60601-1-2:2014 (emission and immunity) according to IEC/CISPR 11:2009 (modified + A1:2010). |
| MR Safety | ASTM F2052-15 | MR safety testing was performed according to ASTM F2052-15, and the device is "MR conditional" in a static 1.5 Tesla magnetic field. (Implies satisfactory performance against the standard). |
| Software Verification | FDA Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices (2005) | Software verification and validation testing results were conducted and submitted according to the guidance. The BEAMSCAN software contains no new functions and was previously cleared with 510(k) #K161807. |
| Bench/Non-clinical Performance | IEC 60731:2016 and specific properties of water phantom systems (radiotherapy dose measurements, detector positioning accuracy, reproducibility, mechanical alignment, design output vs. input) | Verification and validation testing demonstrated that BEAMSCAN MR fulfills the design specification and its intended use. Non-clinical performance testing was performed according to IEC 60731:2016 and specific properties of water phantom systems, including radiotherapy dose measurements (step-by-step), measurement accuracy (detector positioning), reproducibility, and mechanical alignment. |
| Clinical Workflow Validation | Not a formal standard, but demonstration of safe and effective use in intended environment. | Validation of the clinical workflow has been conducted in BEAMSCAN MR validation testing with qualified medical physicists and experienced PTW staff (in the context of pre-treatment quality assurance without a patient). |
| Substantial Equivalence | Equivalence in indications for use, technological characteristics, performance, safety, and effectiveness to predicate device. | The comparison showed that, when used within an MR Radiation Therapy system, the PTW BEAMSCAN MR system is as safe and effective as the predicate device within a non-MR environment. |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document does not specify a distinct "test set" with a number of cases in the traditional sense of a clinical study. The performance evaluation is based on:
- Bench and Non-clinical Testing: These are laboratory-based tests. The "sample size" would relate to the number of measurements taken or the number of units tested. This information is not provided beyond stating that verification and validation were performed.
- Clinical Workflow Validation: This was conducted "with qualified medical physicists and experienced PTW staff." There is no specific number of "cases" or "patients" as the device is for QA and not used with patients. The provenance is internal to the manufacturer (PTW staff) and likely conducted at their facilities or collaborator sites.
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)
No "ground truth" established by external experts in the way typical for AI/diagnostic devices. The "validation of the clinical workflow" was performed by:
- "qualified medical physicists"
- "experienced PTW staff"
The specific number of these individuals or their detailed qualifications (e.g., years of experience) are not provided. Given the nature of a QA device, the "ground truth" for its performance accuracy would be derived from physical dosimetry standards and established protocols, rather than expert interpretation of patient data.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
No adjudication method is mentioned as there isn't a traditional "test set" requiring expert consensus on findings. The performance evaluation relies on objective measurements against engineering specifications and relevant industry 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, an MRMC comparative effectiveness study was not done. This device is a quality assurance tool for radiation therapy systems, not a diagnostic imaging device that assists human readers. Therefore, the concept of "human readers improving with AI assistance" is not applicable here.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
The BEAMSCAN MR is a hardware system with integrated software for data display and processing. It performs "standalone" measurements of beam characteristics. There isn't a human-in-the-loop diagnostic process for the device itself; rather, humans (medical physicists) operate the device to perform QA. The software itself contains "no new functions" and was previously cleared. The focus is on the hardware's performance in an MR environment.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for the device's performance is based on:
- Physical Dosimetry Standards: Compliance with standards like IEC 60731:2016 for radiotherapy dose measurements.
- Engineering Specifications: The device's ability to accurately measure parameters like detector positioning, reproducibility, and mechanical alignment against its design inputs.
- Regulatory Standards: Adherence to electrical safety (IEC 61010-1:2010), EMC (IEC 60601-1-2:2014), and MR safety (ASTM F2052-15) standards.
There is no "expert consensus," "pathology," or "outcomes data" ground truth in the context of this device because it is a measurement tool, not a diagnostic or prognostic one.
8. The sample size for the training set
The document does not explicitly mention a "training set" in the context of machine learning, as this device primarily relies on physics principles and engineering. The "software contains no new functions" and was previously cleared. Therefore, any development data for the original software would have been part of the predicate device's clearance.
9. How the ground truth for the training set was established
Not applicable as there is no mention of a "training set" for machine learning purposes for this device. The software's ground truth (i.e., its correct functionality) would have been established through traditional software verification and validation, ensuring it correctly implements the algorithms for data acquisition, processing, and display as specified by physics principles and dosimetry protocols.
§ 892.5050 Medical charged-particle radiation therapy system.
(a)
Identification. A medical charged-particle radiation therapy system is a device that produces by acceleration high energy charged particles (e.g., electrons and protons) intended for use in 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. When intended for use as a quality control system, the film dosimetry system (film scanning system) included as an accessory to the device described in paragraph (a) of this section, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.