(131 days)
The PedCAT is intended to be used for 3-D imaging of the foot & ankle region, to visualize and assess the osseous and certain soft tissue structures, including joint spaces, bone angles and fractures. This modality is anticipated to be applicable to pediatric* cases as well as adults*, when appropriate diagnosis of a given foot condition is considered necessary.
The PedCAT is a dedicated X-Ray imaging device that acquires a 360 degree rotational X-ray sequence, reconstructs a three-dimensional matrix of the examined volume and produces two dimensional views of this volume. The PedCAT can measure distances and thickness on two dimensional images. Images produced by the PedCAT can be printed or exported on magnetic and optical media. The PedCAT gantry is comprised of an X-ray source, image detector, and motorized gantry. The gantry facilitates the acquisition of a full Xray sequence by the software. The software receives the two dimensional images acquired by the detector, transforms them into three dimensional images and displays them on the workstation monitor for viewing.
This document describes the CurveBeam PedCAT, a computed tomography x-ray system intended for 3-D imaging of the foot & ankle region. The submission is a 510(k) summary, which generally focuses on demonstrating substantial equivalence to a predicate device rather than presenting detailed clinical study results against specific acceptance criteria for performance metrics.
The provided text focuses on establishing substantial equivalence to a predicate device (Imaging Sciences DVT Scanner, K051980) based on similar intended use and technological characteristics. The study that proves the device meets "acceptance criteria" in this context is primarily a comparison to the predicate device and phantom testing to show similar imaging performance.
Here's a breakdown of the requested information based on the provided document:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state "acceptance criteria" with numerical targets for clinical performance metrics (e.g., sensitivity, specificity for fracture detection). Instead, the performance evaluation aims to demonstrate that the PedCAT's imaging characteristics are "authentic and accurate representations of the imaged object, within the expected tolerance for a CBCT device, and very similar to the predicate device."
| Acceptance Criteria (Implied by Substantial Equivalence Claim) | Reported Device Performance (Summary) |
|---|---|
| Imaging Quality - Spatial Resolution | Evaluated using an ACR phantom. Result: "visible line pairs" and "authentic and accurate representations of the imaged object, within the expected tolerance for a CBCT device, and very similar to the predicate device." |
| Imaging Quality - Uniformity of Hounsfield Units (HU's) | Evaluated in water equivalent material phantom. Result: "authentic and accurate representations of the imaged object, within the expected tolerance for a CBCT device, and very similar to the predicate device." |
| Imaging Quality - HU values of various density materials | Evaluated in an ACR phantom. Result: "authentic and accurate representations of the imaged object, within the expected tolerance for a CBCT device, and very similar to the predicate device." |
| Imaging Quality - Osseous details and joint spaces (Anatomic) | Evaluated using an anatomic foot phantom (foot skeleton enclosed in soft tissue equivalent material). Result: "showed osseous details and joint spaces very similar to the predicate device, albeit on a different anatomy but on similar tissue densities." Further confirmed by clinical scans: "substantially similar to the predicate device, in terms of osseous details and joint spaces." |
| Scatter Radiation | Measured in the 2-scan orbit mode. Results: "values were found to be in a very low range and comparable to the predicate device, although slightly higher than single-orbit scans in the PedCAT." |
| Software Functionality (Frame capture & Reconstruction) | Frame capture tools are "identical" (supplied by Varian) and both PedCAT and predicate use FDK back-projection algorithm for CBCT reconstruction. Implied performance is comparable due to shared core components and algorithms. |
| Compliance with Standards | Explicit Criterion: The PedCAT complies with applicable FDA and international standards pertaining to electrical, mechanical, software, EMC, and radiation safety of medical and/or laser devices. Reported Performance: "The PedCAT Computed tomography x-ray system complies with applicable FDA and international standards pertaining to electrical, mechanical, software, EMC, and radiation safety of medical and / or laser devices." |
2. Sample size used for the test set and the data provenance
- Test Set Sample Size (Clinical): "A large collection of patients have been scanned at 2 clinical sites." The exact number of patients is not specified.
- Test Set Sample Size (Phantom):
- ACR phantom
- Water equivalent material phantom
- Anatomic foot phantom (foot skeleton enclosed in soft tissue equivalent material)
- Data Provenance:
- Clinical: Retrospective or Prospective is not explicitly stated, but it was performed "under IRB framework," suggesting a structured approach to clinical data collection. Country of origin not specified.
- Phantom: Bench testing. Specific country not specified, but the submission is to the FDA in the USA.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
The document does not specify the number of experts or their qualifications used to establish ground truth for the clinical data. The statement "the results have been found to be substantially similar to the predicate device, in terms of osseous details and joint spaces" implies a comparison by qualified personnel, but details are not provided. For phantom studies, the "ground truth" is the known characteristics of the phantoms themselves.
4. Adjudication method for the test set
The document does not describe a formal adjudication method for the clinical test set (e.g., 2+1, 3+1). The evaluation appears to be a qualitative comparison of image characteristics ("substantially similar... in terms of osseous details and joint spaces") rather than an adjudication of specific findings against a consensus ground truth.
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
- MRMC Study: No, an MRMC comparative effectiveness study was not explicitly mentioned or described.
- AI Assistance: The PedCAT is described as an "X-Ray imaging device" and the software focuses on image reconstruction and display. There is no mention of Artificial Intelligence (AI) or AI-assisted reading features, so the concept of human reader improvement with/without AI assistance is not applicable to this submission.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, a standalone performance assessment was done, primarily through phantom studies. The characteristics of the resultant volume on the ACR phantom and the water equivalent phantom were evaluated for spatial resolution, uniformity of Hounsfield Units, and HU values of various density materials. The anatomic foot phantom also assessed osseous details and joint spaces. These evaluations are based on the output of the device's imaging and reconstruction algorithms without human interpretation in the loop. The clinical evaluation implicitly assesses the algorithm's output as well, but in a physician-reviewed context.
7. The type of ground truth used
- Phantom Studies: The ground truth was the known physical properties and structures of the phantoms (ACR phantom, water equivalent material phantom, anatomic foot phantom).
- Clinical Studies: The implicit ground truth for comparison was the image quality and diagnostic information provided by the predicate device, particularly regarding "osseous details and joint spaces." There is no mention of pathology, surgery, or long-term outcomes data used as ground truth. This is typical for 510(k) submissions focusing on substantial equivalence in imaging.
8. The sample size for the training set
The document does not mention a training set, as the PedCAT is an imaging device and not described as using machine learning or AI models that require a separate training set. The "software domain" section describes image capture tools and reconstruction algorithms (FDK back-projection), which are not typically "trained" in the machine learning sense. Statistical models that might be 'trained' or parameterized for image reconstruction are established algorithms, not typically requiring a distinct "training set" in a regulatory submission like this.
9. How the ground truth for the training set was established
Not applicable, as no training set for machine learning or AI was described.
§ 892.1750 Computed tomography x-ray system.
(a)
Identification. A computed tomography x-ray system is a diagnostic x-ray system intended to produce cross-sectional images of the body by computer reconstruction of x-ray transmission data from the same axial plane taken at different angles. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.