(133 days)
syngo.CT Dual Energy is designed to operate with CT images based on two different X-ray spectra.
The various materials of an anatomical region of interest have different attenuation coefficients, which depend on the used energy. These differences provide information on the chemical composition of the scanned body materials. syngo.CT Dual Energy combines images acquired with low and high energy spectra to visualize this information. Depending on the region of interest, contrast agents may be used.
The general functionality of the syngo.CT Dual Energy application is as follows:
- · Monoenergetic 1)
- · Brain Hemorrhage
- · Gout Evaluation 1)
- · Lung Vessels
- · Heart PBV
- · Bone Removal
- · Lung Perfusion
- · Liver VNC 1)
- · Monoenergetic Plus 1)
- · Virtual Unenhanced 1)
- Bone Marrow
- · Hard Plaques
- Rho/Z
- · Kidney Stones 1) 2)
- · SPR (Stopping Power Ratio)
- · SPP (Spectral Post-Processing Format) 1)
- · Optimum Contrast 1)
The availability of each feature depends on the Dual Energy scan mode.
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This functionality supports data from Photon-Counting CT scanners.
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Kidney Stones is designed to support the visualization of the chemical composition of kidney stones and especially the differentiation between uric acid stones. For full identification of the kidney stone, additional clinical information should be considered such as patient history and urine testing. Only a well-trained radiologist can make the final diagnosis upon consideration of all available information. The accuracy of identification is decreased in obese patients.
Dual energy offers functions for qualitative and quantitative post-processing evaluations. syngo.CT Dual Energy is a post-processing application consisting of several post-processing application classes that can be used to improve the visualization of the chemical composition of various energy dependent materials in the human body when compared to single energy CT. Depending on the organ of interest, the user can select and modify different application classes or parameters and algorithms.
Different body regions require specific tools that allow the correct evaluation of data sets. syngo.CT Dual Energy provides a range of application classes that meet the requirements of each evaluation type. The different application classes for the subject device can be combined into one workflow.
The provided text is a 510(k) summary for the syngo.CT Dual Energy device, specifically addressing modifications that enable its application classes (Liver VNC, Kidney Stones, Gout Evaluation) to support Photon-Counting CT (PCCT) data. While it discusses performance evaluations, it does not present a formal study with acceptance criteria and detailed quantitative results in the format requested.
The document indicates that the acceptance criteria for these modifications were primarily based on ensuring the existing algorithms and functionality, when applied to PCCT data, yield comparable results to their performance with previously approved dual-source dual-energy (DSDE) data or true non-contrast images, as appropriate. The evaluation appears to be a consistency check rather than a comparative effectiveness study against human readers or a standalone performance study with strict statistical endpoints.
Based on the provided text, here's an attempt to answer the questions, highlighting what information is available and what is not:
Acceptance Criteria and Device Performance Study for syngo.CT Dual Energy (K232155 - PCCT data support)
The provided submission summarizes the non-clinical testing performed to demonstrate that the updated syngo.CT Dual Energy, with its new support for Photon-Counting CT (PCCT) data for Liver VNC, Kidney Stones, and Gout Evaluation, continues to perform as intended and is substantially equivalent to its predicate. The "acceptance criteria" are implied by the performance evaluation statements, focusing on agreement and similarity of results between PCCT data and established methods (DSDE data or true non-contrast images).
1. A table of acceptance criteria and the reported device performance
| Application Class | Implied Acceptance Criteria (Goal) | Reported Device Performance (Summary) |
|---|---|---|
| Liver VNC | Virtual non-contrast (VNC) images from PCCT contrast-enhanced phases should agree well with true non-contrast images. | "Liver VNC was evaluated on four-phase liver scans from the NAEOTOM Alpha. The virtual non contrast (VNC) images from the three contrast enhanced phases agreed well with the true non contrast images." |
| Kidney Stones | For phantom data: Computed stone size and chemical composition from PCCT data should agree with known values. For clinical data: Performance on PCCT data should be similar to performance on already approved dual-source dual-energy (DSDE) data. | "The application Kidney Stones was validated on both phantom data and clinical data. In the phantom scans, the size of the stones and the chemical composition computed from PCCT data agreed with the known size and composition of the stones in the phantoms. In clinical data, the performance on PCCT data was similar to the performance on the already approved dual-source dual-energy (DSDE) data." |
| Gout Evaluation | Volume and position of Gout tophi as determined by PCCT data should be the same as results from already approved DSDE scan mode. | "For Gout, results from PCCT data were directly compared with results from the already approved DSDE scan mode. The volume and the position of Gout tophi were the same for DSDE and PCCT data." |
2. Sample size used for the test set and the data provenance
- Liver VNC: "four-phase liver scans"
- Kidney Stones: "phantom data" (unspecified quantity) and "clinical data" (unspecified quantity)
- Gout Evaluation: Unspecified quantity of data for direct comparison.
Data Provenance:
The data provenance is not explicitly stated in terms of country of origin or whether it was retrospective or prospective. However, the mention of "NAEOTOM Alpha" (a Siemens PCCT scanner) suggests it's likely proprietary or internal test data generated for validation purposes. The phrase "already approved" for DSDE data suggests existing, previously validated clinical data might have been used for comparison.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
This information is not provided in the document. The evaluations described ("agreed well," "similar to," "were the same") imply a comparison method, but the human reference or "ground truth" establishment process for these specific tests is not detailed, nor are the number and qualifications of experts involved.
4. Adjudication method for the test set
This information is not provided in the document. Given the summary nature of the performance data, it's unlikely a formal adjudication process for establishing ground truth for these specific validation tests would be detailed here.
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
No, a MRMC comparative effectiveness study involving human readers assisting with AI assistance versus without AI assistance was not mentioned or described in this 510(k) summary. The study focuses on the device's performance with new data types (PCCT), not on its impact on human reader performance.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, the described performance data appears to be standalone (algorithm only), focusing on the processing capabilities of the syngo.CT Dual Energy software with PCCT data and comparing its output to known values (phantoms) or established results (DSDE data, true non-contrast images). There is no mention of human interaction being part of the evaluation of the algorithm's performance in these specific tests.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- Liver VNC: "True non contrast images" served as the ground truth/reference.
- Kidney Stones:
- For phantom data: "known size and composition of the stones in the phantoms" served as ground truth.
- For clinical data: "already approved dual-source dual-energy (DSDE) data" likely served as the reference for "similar" performance.
- Gout Evaluation: "results from the already approved DSDE scan mode" served as the reference for comparison.
8. The sample size for the training set
The document does not provide any information about the training set size for the algorithms within syngo.CT Dual Energy. Given that the 510(k) is for modifications to support new data types (PCCT) for existing algorithms, it's implied that the core algorithms were developed and trained previously. This submission specifically addresses the validation of these existing algorithms on the new PCCT data.
9. How the ground truth for the training set was established
The document does not provide any information on how the ground truth for the training set (from the original algorithm development) was established.
§ 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.