(22 days)
The XRpad2 4343 HWC-M, when used with a radiographic imaging system, is indicated for use in generating radiographic images of human anatomy for diagnostic X-ray procedures, wherever conventional screen-film (SF), digital radiography (DR), or computed radiography (CR) systems may be used. It is not intended for mammographic use.
The XRpad2 4343 HWC-M is a wireless, lightweight, cassette-sized, flat panel X-ray detector for digital radiography. It fits into a conventional table or wall-stand Bucky, just like a film-screen cassette. The X-ray detector consists of an amorphous silicon flat panel with a directly deposited Csl:Tl scintillator and dedicated read-out, scan, and control electronics, all packaged in a carbon-fiber and aluminum enclosure. The outside dimensions of the detector are 460 mm × 460 mm × 15.5 mm, which fits into a standard X-ray cassette Bucky.
The detector can be integrated with an X-ray system to enable digital radiography.
The XRpad2 4343 HWC-M device, like the predicate, relies on the X-ray Imaging Software Library (XISL), to control the detector from the host computer. The XISL is a C/C++-coded software library that provides parameterized functions to interface the device to a host work station via an IP Network connection. By use of the application programming interface (API) of XISL one can acquire images and configure all use functions of the XRpad2 4343 HWC-M detector.
The provided text describes the acceptance criteria and the study that proves the device meets the acceptance criteria for the XRpad2 4343 HWC-M Flat Panel Detector.
The acceptance criteria are established by demonstrating substantial equivalence to a predicate device (XRpad2 4336 HWC-M) through non-clinical testing. The key acceptance criteria hinge on the comparability of critical image quality performance attributes and compliance with international and FDA recognized consensus standards.
1. A table of acceptance criteria and the reported device performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance (XRpad2 4343 HWC-M) |
|---|---|---|
| Intended Use | Same as predicate (diagnostic X-ray procedures, non-mammographic) | Same as predicate: "generating radiographic images of human anatomy for diagnostic X-ray procedures, wherever conventional screen-film (SF), digital radiography (DR), or computed radiography (CR) systems may be used. It is not intended for mammographic use." |
| Technology/Materials | Similar to predicate | Utilizes similar technology and materials (amorphous silicon flat panel with CsI:Tl scintillator). |
| Design/Construction | Similar to predicate (slight dimensional change) | Similar in design and construction. Primary difference is a 76 mm increase in width, which "does not impact image quality." |
| Image Quality | Comparable to predicate (MTF, DQE) | "This testing demonstrated that critical image quality performance attributes, such as MTF and DQE, of the XRpad2 4343 HWC-M are comparable to the predicate device." |
| Operational Standards | Compliance with international and FDA recognized consensus standards | Complies with IEC and ISO standards and regulations related to medical safety, EMC, and bio-compatibility. Followed guidance for 510(k) for Solid State X-ray Imaging Devices. |
| Safety and Effectiveness | Substantially equivalent to predicate | "Based on the information supplied in this 510(k) Varex Imaging concludes, the XRpad2 4343 HWC-M is substantially equivalent to the currently marketed device, XRpad2 4336 HWC-M (K161966) in terms of safety and effectiveness." |
| Risk Mitigation | Identified risks mitigated and accepted | Risks and hazardous impacts analyzed by FMEA methodology. Specific risk control and protective measures reviewed. "Overall assessment concluded that all identified risks and hazardous conditions were successfully mitigated and accepted." |
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document explicitly states: "A clinical study was not required for the XRpad2 4343 HWC-M device." Therefore, there is no test set of clinical images nor data provenance in the traditional sense for evaluation. The "test set" for proving substantial equivalence was the device itself undergoing non-clinical technical testing.
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, as no clinical study or human expert evaluation was used to establish ground truth.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable, as no clinical study or human expert evaluation was conducted.
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
Not applicable, as no clinical study, MRMC study, or AI assistance is mentioned. This device is an X-ray detector, not an AI-powered diagnostic tool.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. The study was a non-clinical technical evaluation of the flat panel detector's physical and technical performance attributes like MTF and DQE, not an algorithm.
7. The type of ground truth used (expert concensus, pathology, outcomes data, etc)
The "ground truth" for the non-clinical testing was established by technical measurements and compliance with recognized industry standards (IEC, ISO). For image quality attributes like MTF (Modulation Transfer Function) and DQE (Detective Quantum Efficiency), the 'ground truth' is the quantitative measurement of these physical properties as defined by relevant standards.
8. The sample size for the training set
Not applicable, as this is a physical medical device (X-ray detector), not a machine learning model. There is no concept of a "training set" for this type of device submission.
9. How the ground truth for the training set was established
Not applicable, as there is no training set mentioned.
§ 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.