(196 days)
These diodes are used to provide dose verification and quality assurance for paţients undergoing radiation therapy.
The product consists of a waterproof color coded molded plastic hemisphere containing the appropriate buildup material and a radiation sensitive diode attached to a coaxial cable. A BNC connector is supplied for connection to a readout device.
Here's an analysis of the provided text, focusing on acceptance criteria and the study that proves the device meets them:
The provided document is a 510(k) Premarket Notification summary for the Victoreen VeriDose Diodes. This type of regulatory submission is primarily focused on demonstrating substantial equivalence to a predicate device, rather than proving efficacy or meeting specific, independently established acceptance criteria through a comprehensive clinical study.
Therefore, the information presented does not include a detailed study proving the device meets explicit acceptance criteria in the way a clinical trial or performance study for an AI/software device would. Instead, the document lists general specifications that characterize the device's performance, implying these specifications are comparable to or meet the expected performance for such a device, and are substantially equivalent to the predicate device.
Let's break down what is available in the document:
1. Table of Acceptance Criteria and Reported Device Performance
As this is a 510(k) for a physical medical device (radiation detector), the "acceptance criteria" are implied by the listed general specifications of the device, which are then compared to the predicate device (ISORAD Photon Detectors) for substantial equivalence. "Reported device performance" refers to these established specifications.
| Characteristic | Acceptance Criteria (Implied by Specification) | Reported Device Performance (VeriDose Diodes) |
|---|---|---|
| Range | Expected to measure radiation dose rates within a specified range. | 2.0 cGy/minute to 1000 cGy/minute |
| Effective Detection Area | Defined physical area for radiation detection. | 2 mm² |
| Output | Nominal output signal per unit of radiation. | 1.0 nC/R nominal (all models) |
| Cable Length | Standard cable length for connection. | 2 meters |
| Optimal Build-up (Material & Thickness) | Appropriate material and thickness needed for accurate measurement for different energy levels/particles. Compare to predicate. | 1-4 MV Photon: 5 mm H2O equiv. (826 mg/cm²) - Same as Isorad Build-up |
| 6-12 MV Photon: 15 mm H2O equiv. (1500 mg/cm²) - Same as Isorad Build-up | ||
| 12-18 MV Photon: 28 mm H2O equiv. (2800 mg/cm²) - No (compared to Isorad) | ||
| 18-25 MV Photon: 36 mm H2O equiv. (3600 mg/cm²) - No (compared to Isorad) | ||
| 6-25 MeV Electron: 1 mm Al equiv. (275 mg/cm²) - Same as Isorad Build-up | ||
| 100-662 keV Photons: Energy Compensated - No (compared to Isorad) | ||
| Sensitive Area Build-up Shape | Physical characteristic. | Hemispherical |
| Angular Dependence | Variation in measurement based on the angle of radiation incidence. | Less than 5% over 2π hemisphere from perpendicular incidence to 75 degrees; less than 10% from 75 to 90 degrees. |
| Linearity | Consistency of output signal proportional to dose rate. | Better than 0.3% over 2 cGy/min to 1000 cGy/min, provided that dose-per-pulse remains constant. |
| Polarity Options | Availability of different polarity versions. | Both positive and negative polarity versions available for each model. |
| Temperature Sensitivity | Change in measurement per degree Celsius. | Less than 0.3% per degree C. |
| Waterproof/Washable | Environmental resistance features. | Waterproof, washable in cold disinfectant, molded in non-hygroscopic plastic. |
| Connector Type | Standardized connection interface. | BNC coaxial connector. |
Regarding the "Study that proves the device meets the acceptance criteria":
The provided document is a 510(k) summary from 1996. For physical, non-software/AI medical devices, the demonstration of "acceptance criteria" and "proof" typically comes from bench testing and engineering validation comparing the new device's specifications to those of a predicate device, and ensuring it meets its own design specifications. The document summarizes these characteristics, implying that the necessary testing was performed to establish these specifications. However, it does not describe the detailed study methodologies or results.
Based on the prompt's request for information commonly associated with AI/software device studies, much of that information is not applicable or not provided in this type of regulatory submission for a physical device from that era.
Here's an attempt to address the remaining points, noting where information is absent or irrelevant:
2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective)
- Not applicable / not provided. This device is a physical radiation detector. "Test set" and "data provenance" as understood for AI/software are not relevant here. The "testing" would involve characterizing the diode's physical and electrical properties in a laboratory setting, likely under controlled radiation fields, rather than with a "data set."
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)
- Not applicable / not provided. As a physical sensor, there is no "ground truth" established by human experts in the way an AI algorithm needs it for image interpretation. The "truth" in this context would be physical measurements from calibrated radiation sources and established dosimetry standards.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
- Not applicable / not provided. Adjudication methods are used in cases where human interpretation is part of establishing ground truth (e.g., for medical images). This is not relevant for a physical radiation detection device.
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, not applicable. MRMC studies and the concept of "human readers improving with AI" are specific to AI-assisted diagnostic or interpretive tools. This device is a sensor used by medical professionals, not an interpretive AI.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Standalone performance (algorithm only) is not applicable. The device itself is a "standalone" physical sensor. Its performance is based on its physical properties and electrical output, not on an algorithm. It requires a human operator and an "appropriate display device" to interpret its readings.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- The "ground truth" for evaluating this device would be physical dosimetry standards and measurements obtained from highly calibrated and traceable radiation sources (e.g., using primary or secondary standard electrometers and ionization chambers). It would involve comparing the diode's output to these established physical standards under controlled laboratory conditions. This is implied by the specification data, but not explicitly documented as a "ground truth" method.
8. The sample size for the training set
- Not applicable. This device is a physical sensor, not an AI/ML algorithm that requires a training set.
9. How the ground truth for the training set was established
- Not applicable. No training set is involved.
In summary, the provided document is a regulatory submission for a physical medical device (radiation detector) from the 1990s. The concept of "acceptance criteria" is largely met by demonstrating that the device's technical specifications are suitable for its intended use and are substantially equivalent to a predicate device. The detailed study methodologies for establishing these specifications are not included in this type of summary document, and many of the specific questions related to AI/software performance studies are not applicable to this device.
§ 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.