(59 days)
The Gating Reflector Block is an accessory medical device indicated for adult and pediatric patients undergoing radiotherapy treatment simulation and/or delivery. GRB is a reusable device indicated for monitoring patient motion including respiratory patterns.
The Gating Reflector Block is a passive hardware device used for tracking the respiratory motion of the patient. It is intended to be used as an accessory to with Respiratory Gating System Scanners (K213927); TrueBeam STx™, Edge™, VitalBeam (K213977); and RPM Respiratory Gating System 1.7MR2 (K102024) to support motion management during imaging acquisition or radiation therapy treatment.
The Gating Reflector Block (Figure 01) has the following major components:
- Body
- Reflective Markers
The device has 4 mounted optical markers such that the reflected light can be processed by a camera to quantify the displacement of the markers, thus obtaining the patient's breathing curve.
The device consists of a plastic block and back plate and the optical markers. The optical lenses reflect the IR light wavelengths used by parent devices. Their arrangement ensures that the spatial displacement and the rotation of the block is detectable by optical monitoring systems. The alignment to the treatment room lasers is ensured by the printed alignment marks on the top and the sides of the block.
The major function of the device is to act as a surrogate device for tracking patient motion. Current parent devices track respiratory motion after placing the gating block on the chest of the patient. The IR reflectors are used by the parent devices to calculate the position and rotation of the block.
The provided text describes the regulatory filing for a medical device called the "Gating Reflector Block" (GRB). It is a passive hardware accessory used in radiotherapy to track patient motion, primarily respiratory patterns. The filing (K242874) seeks to register the GRB as an individual product, as it was previously cleared as an accessory to other Varian devices.
Based on the provided document, the device (Gating Reflector Block) is a passive hardware device and does not involve an AI algorithm, software, or human-in-the-loop performance studies as described in the prompt's requirements (e.g., MRMC studies, training/test sets, ground truth establishment for AI/software). Therefore, many of the requested details about acceptance criteria and studies (especially those related to AI/software performance) are not applicable to this specific device.
However, I can provide information based on the performance testing that was conducted for this hardware device, which focuses on safety and physical performance characteristics.
Here's a breakdown of the acceptance criteria and study information that is applicable:
1. A table of acceptance criteria and the reported device performance
The document does not present explicit numerical "acceptance criteria" for performance metrics like sensitivity, specificity, or accuracy that would be typical for an AI/software device. Instead, the "acceptance criteria" for a passive hardware device like the GRB are met through demonstrated compliance with relevant standards and successful completion of specific non-clinical tests. The "performance" is reported as the successful demonstration of functionality and safety.
| Acceptance Criteria Category | Reported Device Performance (Summary of Study Results) |
|---|---|
| Biocompatibility | Concluded to possess a low level of biological risk with an acceptable level of patient safety, conducted according to ISO 10993-1:2018 and FDA Guidance. |
| Cleaning, Disinfection, Sterilization, Reprocessing (Cleaning Validation) | Cleaning validation was conducted according to AAMI, ISO standards, and FDA guidelines, assessing the effectiveness of the provided cleaning procedure. The device is supplied nonsterile and is reusable/cleanable. |
| Product Verification and Validation Testing | Underwent formal design verification and validation testing, including usability testing, demonstrating that the device performs as intended. |
| Compliance with Quality System Regulations & Standards | Testing was performed according to FDA Quality System Regulation (21 CFR §820), ISO 13485 Quality Management System Standard, and ISO 14971 Risk Management Standard. |
| Physical Design & Functionality | Consistent physical design (light plastic block with 4 passive reflective markers), dimensions (88mm x 77mm x 53mm), material (ABS 737), and positioning method (on patient's upper abdomen/chest) with the predicate. Measures vertical, lateral, and longitudinal position. |
2. Sample size used for the test set and the data provenance
- Sample Size for Test Set: Not applicable in the context of an AI/software test set. The testing performed was validation and verification of the physical device and its reprocessing instructions. These tests are typically conducted on a representative sample of devices, but a "test set" in the sense of a dataset for algorithm evaluation is not relevant here.
- Data Provenance: Not applicable. This refers to physical device testing, not data collection for an algorithm.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not applicable. Ground truth establishment by experts is relevant for AI/software diagnosis/prognosis, not for a passive hardware device like the GRB. The "ground truth" for this device's performance relates to its physical properties, functionality, and safety as determined through engineering and biological testing.
4. Adjudication method for the test set
- Not applicable. Adjudication methods are used in studies involving human interpretation or AI output, not for the physical performance validation of a hardware 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. An MRMC study is relevant for AI-assisted diagnostic or clinical decision support software. The Gating Reflector Block is a passive hardware device for motion tracking, not an AI or software product.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- No. This device is a passive hardware component. It does not contain an algorithm or software. Its performance is intrinsically linked to its use within a larger system (like the Respiratory Gating System Scanners) rather than as a standalone algorithmic product.
7. The type of ground truth used
- The "ground truth" for this device's acceptance is based on:
- Engineering specifications and measurements: For dimensions, material properties, and marker effectiveness.
- Standardized test methods: For biocompatibility (e.g., ISO 10993 series) and cleaning validation (AAMI, ISO standards).
- Regulatory compliance: Adherence to FDA Quality System Regulation (21 CFR §820), ISO 13485, and ISO 14971.
- Demonstrated performance: The device "performs as intended" based on product verification and validation.
8. The sample size for the training set
- Not applicable. This device is a passive hardware component, not an AI system that requires a training set.
9. How the ground truth for the training set was established
- Not applicable, as there is no training set for this hardware device.
In Summary:
The K242874 filing for the Gating Reflector Block pertains to a physical medical device accessory. The "acceptance criteria" and "study" described in the document are focused on demonstrating the device's physical performance, safety, and compatibility with existing Varian systems through non-clinical testing and adherence to established regulatory and industry standards, rather than evaluating an AI algorithm's diagnostic or predictive capabilities. The device has been on the market for 13 years with approximately 27,000 units in the field, further supporting its established performance and safety.
§ 892.1750 Computed tomography x-ray system.
(a)
Identification. A computed tomography x-ray system is a diagnostic x-ray system intended to produce cross-sectional images of the body by computer reconstruction of x-ray transmission data from the same axial plane taken at different angles. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.