(132 days)
The Cios Alpha is a mobile X-Ray system designed to provide X-ray imaging of the anatomical structures of patient during clinical applications. Clinical applications may include but are not limited to: interventional fluoroscopic, gastro- intestinal, endoscopic, urologic, pain management, orthopedic, neurologic, vascular, cardiac, critical care and emergency room procedures. The patient population may include pediatric patients.
The Cios Alpha mobile fluoroscopic C-arm X-ray System is designed for the surgical environment. The Cios Alpha provides comprehensive image acquisition modes. The system consists of two major components:
a) The C-arm with an X-ray source on one side and the flat panel detector on the opposite side. The c-arm can be angulated in both planes and lifted vertically, shifted to the side and moved forward/backward by an operator.
b) The second component is the image display station with a moveable trolley that holds the image processing and storage system, and the image display. Both components are connected to each other with a cable.
Here's an analysis of the acceptance criteria and study information provided in the document for the Cios Alpha (VA30) device:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state "acceptance criteria" for quantitative performance metrics in a pass/fail format. Instead, it presents a comparison of the Subject Device's (Cios Alpha (VA30)) performance to its Predicate (Cios Alpha (VA10)) and Reference Devices for Solid State X-Ray Imaging (SSXI) specifications. The implication is that comparable or better performance is the acceptance criterion for the SSXI metrics.
| SSXI Metric | Acceptance Criteria (Implied - Comparable or Better) | Reported Cios Alpha (VA30) Performance | Predicate Cios Alpha (VA10) Performance | Reference Ziehm Vision RFD Performance | Reference Ziehm Solo FD Performance |
|---|---|---|---|---|---|
| Imaging Modes | Pulsed fluoroscopy | Pulsed fluoroscopy | Pulsed fluoroscopy | Pulsed fluoroscopy | Pulsed Fluoroscopy, Digital Spot |
| DQE | Comparable or better than Predicate (76%) and Reference (70%) | 75% (small), 72% (large) | 76% | Information Not Available | 70% |
| Dynamic Range | Comparable or better than Predicate (94dB) and Reference (Equivalent) | 96dB | 94dB | Information Not Available | Equivalent |
| Modulation Transfer Function (MTF) | Comparable or better than Predicate (55% at 1 Lp/mm) and Reference (4 Lp/mm) | 60% at 1 lp/mm (small), 58% at 1 lpmm (large) | 55% at 1 Lp/mm | Information Not Available | 4lp/mm |
| Digitization Depth | 16 bit | 16 bit | 16 bit | 16 bit | 16 bit |
| Pixel Pitch | Not explicitly stated as a target, but the change from 194μm (Predicate) to 152μm (Subject) is a technological characteristic shown as an improvement. | 152 μm | 194μm | 194 μm | 100 μm |
| Field of View | Matching the predicate and reference devices. | Small FD: 20x20, 15x15, 10x10; Large FD: 30x30, 20x20 | Small FD: 20x20, 15x15, 10x10; Large FD: 30x30, 20x20 | FPD 20 cm: 20, 15, 10 | FPD 20 cm: 20, 15, 10 |
Additional Acceptance Criteria (General):
- Compliance with voluntary standards (Table 3), FDA Guidance Documents (Table 4).
- Software verification and validation meeting acceptance criteria.
- Risk analysis completed and hazards mitigated.
- Human Factors Usability Validation showing addressing human factors and successful clinical use tests.
- Cybersecurity requirements met.
Study Proving Device Meets Acceptance Criteria:
The document describes several non-clinical performance tests and analyses to demonstrate that the Cios Alpha (VA30) meets the acceptance criteria, primarily for substantial equivalence to its predicate devices.
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: The document does not specify a distinct "test set" sample size in terms of patient data or number of images for evaluating the SSXI metrics. The performance evaluation seems to be based on engineering bench testing of device capabilities rather than a separate clinical image set.
- Data Provenance: The data provenance for the SSXI metrics and other performance tests is non-clinical bench testing. The document states: "Performance tests were conduct[ed] to test the functionality of the Cios Alpha (VA30)." It also mentions "Additional engineering bench testing was performed including: the non-clinical testing identified in the guidance for submission of 510(k) s for Solid State X-Ray Imaging Devices (SSXI); demonstration of system performance; and an imaging performance evaluation."
- The "clinical images are not required" statement further confirms the non-clinical nature of the specific SSXI evaluation.
- The Human Factor Usability Validation mentions "clinical use tests with customer report and feedback form," which implies some level of prospective, real-world (or simulated real-world) interaction, but specific sample sizes are not provided.
- The origin of the data is Siemens Healthcare GmbH Corporate Testing Laboratory and internal verification/validation processes.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- The document does not describe the use of experts to establish ground truth for a test set in the traditional sense of image interpretation for diagnostic accuracy. The testing primarily focuses on technical specifications of the imaging system itself.
- For the Human Factors Usability Validation, "customer report and feedback form" are mentioned, implying input from users (healthcare professionals), but no specific number or detailed qualifications are provided.
4. Adjudication Method for the Test Set
- Given that the primary performance evaluation described is non-clinical bench testing of engineering specifications (SSXI metrics), an adjudication method for a test set based on expert consensus would not be applicable or mentioned. The "ground truth" for these metrics is objectively measured device performance.
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 MRMC comparative effectiveness study is mentioned. This submission is for an imaging system (C-arm X-ray system), not an AI-powered diagnostic algorithm that assists human readers. While it includes "new software functions" like "Target Pointer," which "enables the automatic detection of K-wires and displays the trajectory," the document does not present a study evaluating the impact of this feature on human reader performance or diagnostic accuracy.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
- The document evaluates the Cios Alpha as an imaging system, not a standalone AI algorithm. While it contains new software features, the performance metrics discussed (e.g., DQE, MTF) are system-level imaging characteristics. The "Target Pointer" feature performs automatic detection, but its standalone performance (e.g., accuracy of K-wire detection) is not detailed in the provided text. The overall context is regulatory clearance for hardware and software modifications of an existing medical device, not a new AI-enabled diagnostic device undergoing standalone performance evaluation.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
- For the SSXI performance metrics (DQE, Dynamic Range, MTF, etc.), the "ground truth" is based on objective physical measurements and technical standards. These are inherent properties of the imaging system's detector and processing.
- For software functions, "ground truth" is established through detailed software testing to confirm they "worked as intended" according to specifications and requirements.
- For Human Factors, ground truth would relate to usability and safety observations and feedback during "clinical use tests."
8. The Sample Size for the Training Set
- The document does not mention a training set sample size. This is expected as the submission primarily concerns an imaging system rather than a machine learning algorithm requiring a distinct training phase with annotated data. Although new software features are present, the submission focuses on their validation as part of the overall device.
9. How the Ground Truth for the Training Set Was Established
- Since no training set is discussed, the method for establishing its ground truth is also not applicable in this document.
§ 892.1650 Image-intensified fluoroscopic x-ray system.
(a)
Identification. An image-intensified fluoroscopic x-ray system is a device intended to visualize anatomical structures by converting a pattern of x-radiation into a visible image through electronic amplification. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II (special controls). An anthrogram tray or radiology dental tray intended for use with an image-intensified fluoroscopic x-ray system only is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9. In addition, when intended as an accessory to the device described in paragraph (a) of this section, the fluoroscopic compression device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.