(48 days)
The CRUXCAN (CRX-1000) is indicated for capturing, digitization and processing of intra-oral x-ray images stored in imaging plate recording media.
The CRUXCAN (CRX-1000) is a dental computed radiography system and is intended to produce digital X-Ray images for dental radiography purposes. It consists of a scanner, reusable imaging plates and workstation software. This device scans X-Ray exposed imaging plate and produces X-Ray image in digital form. Then, digital image is transferred to workstation for further processing and routing. The design features a built-in erase function and a color touch-screen LCD panel without physical push buttons for device operation. This device is intended to be operated in a radiological environment by qualified staff. The Imaging Plate is a polyester film made of densely applied particles of inorganic crystals called photostimulable phosphor. It is a flexible X-ray sensor for the CR system which can be used with a conventional medical X-ray imaging system and can be employed as a substitute for the screen/film system. The phosphor layer has a function of recording an X-ray image. This photostimulable phosphor is a special luminescent material which stores X-ray energy and emits light proportional to the stored X-ray energy when stimulation energy such as visible light is irradiated onto it. CRUXCAN TWAIN Driver and Viewer which transmit and display images are substantially equivalent to the predicate device software as well in terms of functions and principle of operations. The User interface is slightly different but the differences in design do not raise questions in device effectiveness.
Here's an analysis of the provided text regarding the acceptance criteria and the study proving the device meets them:
The document (K183637) describes the CRUXCAN (CRX-1000), a dental computed radiography system. The acceptance criteria and performance study presented here are primarily focused on demonstrating substantial equivalence to predicate devices rather than proving a specific clinical performance threshold against a predefined ground truth or an improvement over human readers.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly derived from the comparative performance shown against the predicate devices. The "SE Note" column indicates whether the subject device is considered "Equivalent" or if there's "No issue on safety and effectiveness" despite differences. This means the subject device's performance, even if quantitatively different, is considered acceptable because it's either comparable or superior without raising new safety/effectiveness concerns.
| Category | Acceptance Criteria (Implied by Predicate) | Reported Device Performance (CRUXCAN) | SE Note |
|---|---|---|---|
| Indications for Use | Capturing, digitization, and processing of intra-oral x-ray images. | Capturing, digitization, and processing of intra-oral x-ray images. | Equivalent |
| Communication | DICOM (Predicate) | TIFF / Raw Format | No issue on safety and effectiveness |
| Power Supply | 50 – 60 Hz, 100 - 240 V ~ | 50 – 60 Hz, 100 - 240 V ~ | Equivalent |
| Operating System | Windows NT 4.0/2000/XP (Predicate 1), Windows 7 or 8 (Predicate 2) | Windows 10 or higher | Equivalent |
| X-ray Absorber | Imaging Plate | Imaging Plate | Equivalent |
| Cassette Size | Size 0, 1, 2, 3 (specific mm dimensions) | Size 0, 1, 2, 3 (specific mm dimensions) | No issue on safety and effectiveness |
| Pixel Size | 40 um, 64 um (Predicate 1); 30um, 60um (Predicate 2) | 25 um, 50 um | No issue on safety and effectiveness (Subject device has smaller pixels, considered better) |
| Dynamic Range (Acq.) | 14 bit (Predicates) | 8bit / 16 bit | Equivalent (Subject device offers wider dynamic range with 16-bit) |
| Resolution | 12.5 lp/mm @ 40um (Predicate 1); 16.7 lp/mm@30um (Predicate 2) | 14.0lp/mm @ 25um | No issue on safety and effectiveness (Subject device's resolution is comparable/better) |
| DQE at 10% eff. | 2.4 lp/mm (Predicates) | 2.8 lp/mm | No issue on safety and effectiveness (Subject device has better DQE) |
| MTF at 3lp/mm | 32% (Predicates) | 35% | No issue on safety and effectiveness (Subject device has better MTF) |
| Max. Resolution | 40um (Predicate 1); 30um (Predicate 2) | 25um | No issue on safety and effectiveness (Subject device has better max resolution) |
2. Sample Size Used for the Test Set and Data Provenance
The document states that "Performance studies were conducted on the device imaging plate according to the FDA guidance 'Guidance for the Submission of 510(k)s for Solid State X-ray Imaging Devices'." However, it does not specify the sample size used for performance testing (e.g., number of images, number of patients).
Furthermore, the data provenance (e.g., country of origin, retrospective or prospective) for any images used in the performance evaluation is not mentioned in the provided text.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The provided document does not mention the use of experts to establish a ground truth for a test set in the context of clinical performance or diagnostic accuracy. The performance evaluation focuses on technical imaging characteristics (e.g., DQE, MTF, resolution).
4. Adjudication Method for the Test Set
Since there is no mention of a test set requiring expert interpretation or establishing clinical ground truth, there is no adjudication method described.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study was done. The document explicitly states: "Clinical testing was not necessary for the subject device, in order to demonstrate substantial equivalence." Therefore, there is no information on the effect size of human readers improving with AI vs. without AI assistance as this type of study was not conducted.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
The device is an imaging system (scanner, imaging plate, workstation software) that produces images, rather than an AI algorithm for image analysis. Therefore, the concept of a "standalone" algorithm-only performance as typically applied to AI CAD systems does not directly apply in the context presented. The performance tests ("Performance studies were conducted on the device imaging plate") describe the technical capabilities of the imaging system itself.
7. Type of Ground Truth Used
The ground truth for the performance tests appears to be technical measurements and comparisons of physical imaging characteristics (e.g., lp/mm for resolution, percentage for MTF, lp/mm for DQE) against established engineering standards and the specifications of predicate devices. This is not a clinical ground truth like pathology or outcomes data.
8. Sample Size for the Training Set
The document does not mention a training set as this device is a hardware/software system for image acquisition and processing, not a machine learning algorithm that requires a training set in the typical sense.
9. How the Ground Truth for the Training Set Was Established
As no training set is mentioned or applicable in the context of this traditional medical device evaluation for image acquisition, there is no information on how ground truth was established for a training set.
§ 872.1800 Extraoral source x-ray system.
(a)
Identification. An extraoral source x-ray system is an AC-powered device that produces x-rays and is intended for dental radiographic examination and diagnosis of diseases of the teeth, jaw, and oral structures. The x-ray source (a tube) is located outside the mouth. This generic type of device may include patient and equipment supports and component parts.(b)
Classification. Class II.