(28 days)
VIVIX-S 1751S series is used for the general-purpose diagnostic procedures, and as well as intended to replace radiographic film/ screen systems. The VIVIX-S 1751S series is not intended for mammography applications.
VIVIX-S 1751S, whose model name is VIVIX-S 1751S with 17X51 inches of imaging area. The device intercepts x-ray photons, and its Gadox (Gadolinium Oxysulfide) scintillator emits visible spectrum photons that illuminate an array of photo (a-SI)-detectors that create electrical signals. After the electrical signals are generated, it is converted to digital value, and the software acquires and processes the data values from the detector. The resulting digital images will be displayed on monitors. These devices should be integrated with an operating PC and an X-Ray generator. The detector can communicate with the generator by cable. It is utilized for capturing and transfer of digital x-ray images for radiography diagnosis. The X-ray generator and the imaging software are not part of the VIVIX-S 1751S.
Acceptance Criteria and Study for VIVIX-S 1751S Digital X-ray Detector
The VIVIX-S 1751S Digital X-ray detector was evaluated for substantial equivalence to its predicate device (K181003, VIVIX-S 1717V) through non-clinical performance testing and a clinical image concurrence study.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the VIVIX-S 1751S are based on demonstrating performance equivalent to or better than the predicate device (VIVIX-S 1717V). Specifically, the device was tested against recognized performance metrics for X-ray detectors.
| Parameter | Acceptance Criteria (Predicate Device K181003) | Reported Device Performance (VIVIX-S 1751S) | Met Acceptance Criteria? |
|---|---|---|---|
| Image Quality | |||
| DQE (1lp/mm) | FXRD-1717VA: 40~60 (typ. 48%) | ||
| FXRD-1717VB: 20~40 (typ. 27%) | FXRD-1751SB: 20% (for Gd2O2S:Tb scintillator) | Equivalent | |
| MTF (1lp/mm) | FXRD-1717VA: 50~70 (typ. 70%) | ||
| FXRD-1717VB: 40~60 (typ. 58%) | FXRD-1751SB: 40% (for Gd2O2S:Tb scintillator) | Equivalent | |
| Resolution | 3.5 lp/mm | 3.5 lp/mm | Yes |
| Pixel Pitch | 0.14mm | 0.14mm | Yes |
| Active Area | 430.08 x 430.08 (mm) | 430.08(mm) x 430.08(mm) | |
| 430.08(mm) x 860.16(mm) | |||
| 430.08(mm) x 1290.24(mm) | Yes (offers larger options) | ||
| Pixel Size | 140 μm | 140 μm | Yes |
| Grayscale | 16 bit | 16 bit | Yes |
| Spatial Resolution | 3.5lp/mm | 3.5lp/mm | Yes |
| Functional Equivalence | |||
| Intended Use | General diagnostic procedures, replace film/screen systems, not mammography. | General diagnostic procedures, replace film/screen systems, not mammography. | Yes |
| Operating Principle | X-ray photons strike scintillator, visible light, electric charge, digital value. | X-ray photons strike scintillator, visible light, electric charge, digital value. | Yes |
| Design Features | Similar to predicate | Similar to predicate | Yes |
| Communication Method | Wired, Max. 1Gbps | Wired, Max. 1Gbps | Yes |
| Scintillator Materials | Gd2O2S:Tb, Csl:TI | Gd2O2S:Tb (Csl:TI type not available for this model) | Equivalent |
| Active Array | 3072 x 3072 pixels | 3072 x 3072 pixels | |
| 3072 x 6144 pixels | |||
| 3072 x 9216 pixels | Yes (offers larger options) | ||
| Method of Generator Interface | DR Trigger, AED, Passive Trigger | DR Trigger, AED | Equivalent (Passive Trigger omitted) |
| Technology | Structured scintillator for efficiency and resolution. | Structured scintillator for efficiency and resolution. | Yes |
| Principle of Operation | X-ray conversion to visible light then electric charge. | X-ray conversion to visible light then electric charge. | Yes |
Note: While the exact DQE and MTF values vary for the specific FXRD-1751SB model compared to some predicate models (FXRD-1717VA vs FXRD-1717VB), the applicant states "Similar performance as follow" and declares the performance as "Equivalent," suggesting the overall performance is within an acceptable range for substantial equivalence.
2. Sample Size Used for the Test Set and Data Provenance
The provided summary does not explicitly state the specific sample size used for the clinical image concurrence study test set. It mentions "a single-blinded concurrence study." The data provenance (e.g., country of origin, retrospective or prospective) for this clinical study is also not detailed in the provided information.
3. Number of Experts and Qualifications for Ground Truth
The number of experts used to establish the ground truth for the clinical test set and their specific qualifications (e.g., "radiologist with 10 years of experience") are not specified in the provided 510(k) summary. It only indicates that "CDRH's Guidance for the Submission of 510(k)'s for Solid State X-ray Imaging Devices was conducted" and that it was a "single-blinded concurrence study."
4. Adjudication Method
The adjudication method for the test set is not explicitly stated. The summary mentions "a single-blinded concurrence study," which implies a comparison of images by experts, but the process for resolving disagreements or establishing a final ground truth is not described.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
There is no indication that a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was done to assess how much human readers improve with AI vs. without AI assistance. The device is a digital X-ray detector, not an AI-powered diagnostic tool, and the study described is a comparison of image diagnostic capability between two detector models.
6. Standalone (Algorithm Only) Performance Study
A standalone performance study of the algorithm only without human-in-the-loop performance is not applicable in the context of this device. The VIVIX-S 1751S is a digital X-ray detector, a hardware component that produces images for human interpretation, not an independent algorithm for diagnosis. The non-clinical performance (DQE, MTF, resolution) can be considered "standalone" in terms of objective image quality metrics of the device itself.
7. Type of Ground Truth Used
For the clinical study, the ground truth was established through expert concurrence. The summary states that the study "confirmed that the new x-ray detectors VIVIX-S 1751S provide images of equivalent diagnostic capability to the predicate devices." This implies that expert readers (though unspecified in number or qualifications) evaluated the images and concurred on their diagnostic equivalence. Pathology or outcomes data are not mentioned as the ground truth.
8. Sample Size for the Training Set
The provided 510(k) summary describes a digital X-ray detector, which is a hardware device for image acquisition. This device does not have a "training set" in the context of artificial intelligence or machine learning algorithms. Its design and performance are based on physical and technical specifications.
9. How the Ground Truth for the Training Set was Established
As clarified in point 8, the concept of a "training set" and associated "ground truth" for a training set is not applicable to this device as it is a digital X-ray detector, not an AI/ML diagnostic software. The performance evaluations are based on engineering specifications and clinical comparison to a predicate device.
§ 892.1680 Stationary x-ray system.
(a)
Identification. A stationary x-ray system is a permanently installed diagnostic system intended to generate and control x-rays for examination of various anatomical regions. 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). A radiographic contrast tray or radiology diagnostic kit intended for use with a stationary 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.