(82 days)
The Stingray DR Solid State X-ray Imaging Device is intended for use in general radiographic examinations and applications wherever conventional screen-film systems may be used (excluding fluoroscopy, angiography, and mammography).
The Stingray DR system uses a flat panel x-ray detector that contains a CsI Scintillator and a Amorphous Si TFT array for conversion of X-rays into an electronic digital image. This system is to be used as a replacement for Screen film x-ray devices for X-ray images. The Stingray DR system has a Personal computer that is used for image storage and retrieval and image processing. The system allows for post processing of images. This allows for the potential to use images that might have been useless if taken on film due to, for example, incorrect technique since the Stingray DR system can post process the images, modify the output look up table and possibly bring out data that could not be seen under normal circumstances.
The provided document is a 510(k) premarket notification for a medical device (Stingray DR), which aims to demonstrate "substantial equivalence" to existing legally marketed predicate devices, rather than establishing de novo acceptance criteria and conducting a study to meet them in the same way a novel device might. The core of a 510(k) submission is to show that the new device performs "the same functions in the same environment" as its predicates and has "the same resolution".
Therefore, the analysis below is based on the information provided in the 510(k) summary, interpreting "acceptance criteria" as the performance metrics used for comparison to predicate devices, and "study" as the comparative analysis presented to justify substantial equivalence.
1. Table of "Acceptance Criteria" (Predicate Device Performance) and Reported Device Performance
For a 510(k) submission, the "acceptance criteria" are implicitly defined by the performance characteristics of the predicate devices. The InfiMed Stingray DR system aims to meet or exceed these characteristics to demonstrate substantial equivalence.
| Feature/Item | "Acceptance Criteria" (Predicate Device Performance) | InfiMed Stingray DR Reported Performance |
|---|---|---|
| Flat Panel Producer | Trixell (Philips, Siemens) | Trixell |
| Detector Material | a-Si sensor array with CsI scintillator | a-Si sensor array with CsI scintillator |
| Detector Dimensions | 17" x 17" | 17" x 17" |
| Pixel Size | 143 x 143 microns | 143 x 143 microns |
| Detector Element Matrix | 2981 x 3021 | 2981 x 3021 |
| Dynamic Range | 14 bits | 14 bits |
| Spatial Resolution | Up to 3.5 lp/mm (Philips), 3.5 lp/mm (Siemens) | 3.5 lp/mm |
| External Connectivity | DICOM 3.0 compatible | DICOM 3.0 compatible |
| Operator Console | Graphical User Interface based | Graphical User Interface based |
| Image Processor | Sun Ultra SPARC (Philips) or Pentium based PC (Siemens) | Pentium based PC |
| Image Storage | Hard Drive | Hard Drive |
| Operating System | UNIX (Philips) or Windows NT (Siemens) | Windows NT |
| Total Image Processing time | Not Available (for Philips/Siemens), 30 seconds (Canon) | 30 seconds per image |
2. Sample Size Used for the Test Set and Data Provenance
The document does not report specific sample sizes for a dedicated test set in the traditional sense of a clinical trial. The "study" here is a technical comparison against predicate devices. The performance data, specifically the spatial resolution, is demonstrated against the claimed specifications of existing, approved devices (Philips Digital Diagnost, Siemens THORAX FD and MULTIX FD, Canon Digital Radiography System).
- Test Set Description: Not applicable in the context of human-read or image-based test sets with patient data. The "test set" effectively consists of the published specifications and performance claims of the predicate devices.
- Data Provenance: The data provenance for the performance characteristics (e.g., spatial resolution) of the InfiMed Stingray DR would typically come from internal engineering and lab testing conducted by Trixell (the flat panel producer) and InfiMed. The document doesn't specify the country of origin of this test data, but given that InfiMed is located in Liverpool, NY, USA, it's likely testing was conducted there or by Trixell (a European company at the time) and validated by InfiMed. The data for predicate devices is based on their respective 510(k) submissions or publicly available specifications. Whether InfiMed performed prospective or retrospective comparisons against these specifications is not explicitly stated, but it would have involved prospective measurements on the Stingray DR system and retrospective comparison to predicate device specifications.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
Not Applicable.
Since this is a technical comparison for substantial equivalence rather than a clinical performance study involving diagnostic accuracy, there were no human experts used to establish a "ground truth" for a patient-image test set. The ground truth for the device's technical specifications (like spatial resolution) is established through standardized physical measurements and engineering tests.
4. Adjudication Method for the Test Set
Not Applicable.
There was no adjudication method (e.g., 2+1, 3+1) because there was no human interpretation of images or establishment of ground truth by multiple experts in the reported comparison.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No.
A Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not conducted and is not mentioned in the provided text. This type of study would typically assess the impact of the device on human reader performance, which is not the focus of this 510(k) submission.
6. Standalone (Algorithm Only) Performance Study
The provided information focuses on the entire "Stingray DR system" which includes the detector, image processing, and a controlling PC. While the document mentions "defect compensation and image correction algorithms" as part of the system, it does not report a standalone performance study specifically for the algorithm without human-in-the-loop performance. The performance metric reported (spatial resolution) is a characteristic of the overall imaging chain.
7. Type of Ground Truth Used
The "ground truth" for the comparison is primarily based on technical specifications and physical performance measurements (e.g., spatial resolution measured in lp/mm). These are objective, quantifiable metrics derived from standard test patterns and methods, rather than clinical outcomes, pathology, or expert consensus on patient images.
8. Sample Size for the Training Set
Not Applicable.
The document does not refer to a "training set." As a 510(k) for a digital radiography system, it's not an AI/ML device in the modern sense that would require a distinct training set for algorithm development in this context. The "defect compensation and image correction algorithms" would have been developed and tuned using internal engineering data, but this is not disclosed as a "training set" with a specified sample size.
9. How the Ground Truth for the Training Set Was Established
Not Applicable.
Since there is no mention of a "training set" in the context of an AI/ML algorithm requiring ground truth, this information is not provided. The performance (e.g., spatial resolution) of the system itself is validated through physical measurements and comparisons to predicate device specifications.
§ 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.