(113 days)
This computed tomography system is intended to generate and process cross-sectional images of patients by computer reconstruction of x-ray transmission data.
The images delivered by the system can be used by a trained physician as an aid in diagnosis. The images delivered by the system can be used by trained staff as an aid in diagnosis, treatment preparation and radiation therapy planning.
This CT system can be used for low dose lung cancer screening in high risk populations *
- As defined by professional medical societies. Please refer to clinical literature, including the results of the National Lung Screening Trial (N Engl J Med 2011; 365:395-409) and subsequent literature, for further information.
The subject device SOMATOM CT Scanner Systems with SOMARIS/7 syngo CT VB20 are Computed Tomography X-ray Systems which feature one (single source) or two (dual source) continuously rotating tubedetector system and function according to the fan beam principle. The SOMATOM CT Scanner Systems with Software SOMARIS/7 syngo CT VB20 produces CT images in DICOM format, which can be used by trained staff for post-processing applications commercially distributed by Siemens Healthcare and other vendors as an aid in diagnosis, treatment preparation and therapy planning support (including, but not limited to, Brachytherapy, Particle including Proton Therapy, External Beam Radiation Therapy, Surgery). The computer system delivered with the CT scanner is able to run optional post processing applications.
The platform software for the SOMATOM CT Scanner Systems, SOMARIS/7 syngo CT VB20, is a commandbased program used for patient management, data management, X-ray scan control, image reconstruction, and image archive/evaluation.
Here's an analysis of the acceptance criteria and supporting study information based on the provided text, broken down by your requested points:
Acceptance Criteria and Study Information for SOMATOM CT Scanner Systems-Software Version SOMARIS/7 syngo CT VB20
The provided document (a 510(k) summary) describes an update to existing Computed Tomography (CT) scanner systems (SOMATOM Force, SOMATOM Definition Flash, SOMATOM Drive, SOMATOM Definition Edge, SOMATOM Definition AS Open, SOMATOM Definition AS/AS+, SOMATOM Confidence, and SOMATOM Edge Plus) with new software version SOMARIS/7 syngo CT VB20. The primary goal of the submission is to demonstrate substantial equivalence to previously cleared predicate devices (K173630 and K173607).
The document does not explicitly list specific numerical acceptance criteria for device performance beyond stating that "all software specifications have met the acceptance criteria" and "the SOMATOM CT Scanner Systems perform comparably to the predicate devices." It focuses on confirming the updated device maintains the safety and effectiveness of the predicate devices.
1. Table of Acceptance Criteria and Reported Device Performance
As specific numerical acceptance criteria are not presented in the document, I will infer the high-level acceptance criteria from the submission's focus on demonstrating substantial equivalence and list the general performance statements made.
| Acceptance Criteria (Inferred) | Reported Device Performance |
|---|---|
| Safety and Effectiveness Equivalence: Device maintains equivalent safety and effectiveness to predicate devices. | "The subject and predicate devices are based on the following same technological elements: Scanner Principle, System Acquisition, Iterative Reconstruction, Workplaces, Patient table, Patient table foot switch for movement, Tin filtration technology, Stellar detector technology." |
| "Testing and validation is completed. Test results show that the subject devices, the SOMATOM CT Scanner Systems, are comparable to the predicate devices in terms of technological characteristics and safety and effectiveness and therefore are substantially equivalent to the predicate devices." | |
| "The non-clinical data supports the device and the hardware and software verification and validation demonstrates that the subject device SOMATOM CT Scanner Systems should perform as intended in the specified use conditions." | |
| Conformance to Standards: Device complies with relevant electrical safety, EMC, software, and risk management standards. | "Electrical Safety and Electromagnetic Compatibility (EMC) testing were conducted on the SOMATOM CT Scanner Systems in accordance with the following standards: 60601-2-44, and 60601-1-2. A list of recognized and general consensus standards considered for the subject devices is provided as Table 9." (Table 9 and 10 list numerous IEC, ANSI AAMI, NEMA, and ISO standards). |
| "Software Documentation for a Moderate Level of Concern software per FDA's Guidance Document... is also included... The Risk Analysis was completed and risk control implemented to mitigate identified hazards." | |
| Software Specifications Met: All software features and updates function as intended. | "The test results show that all of the software specifications have met the acceptance criteria." |
| Verification and Validation: Comprehensive testing proves the device's claims. | "The modifications described in this Premarket Notification were supported with verification and validation testing." |
| "Verification and validation testing of the device was found acceptable to support the claim of substantial equivalence." | |
| Cybersecurity: Device meets cybersecurity requirements. | "Siemens conforms to the Cybersecurity requirementing a process of preventing unauthorized access, modifications, misuse or denial of use, or the unauthorized use of information that is stored, accessed, or transferred from a medical device to an external recipient... is included within this submission." |
| Image Quality / Performance (Implicit): Image reconstruction and diagnostic aid functionality are maintained or improved. | "Non-clinical test (integration and functional) including phantom tests were conducted for the SOMATOM CT Scanner Systems during product development." |
| "dosimetry and imaging performance, and analysis of phantom images to assess device and feature performance during product development." (The document implies these tests confirmed performance but doesn't provide specific numerical results). |
2. Sample Size Used for the Test Set and Data Provenance
The document states that "phantom tests were conducted" and refers to "dosimetry and imaging performance, and analysis of phantom images to assess device and feature performance." However, no specific sample size for the test set (number of phantom scans, patient data, etc.) is provided.
Data Provenance: The tests are described as "non-clinical test (integration and functional) including phantom tests... during product development." This indicates that the testing was conducted internally by the manufacturer,Siemens, likely on prototypes or production units, using phantoms. There is no mention of human subject data, country of origin, or whether the tests utilized retrospective or prospective data. The nature of phantom studies typically makes them prospective in this context.
3. Number of Experts Used to Establish Ground Truth and Qualifications
The document does not provide information on the number of experts used to establish ground truth or their specific qualifications (e.g., number of radiologists, years of experience). Given the nature of this submission (software upgrade for a CT system, focusing on technical performance and substantial equivalence rather than a new diagnostic algorithm's clinical efficacy), it's less likely to involve extensive expert-driven ground truth establishment as would be seen for AI/CADe devices. The "ground truth" for technical performance is typically established via physical measurements and established phantom metrics.
4. Adjudication Method for the Test Set
The document does not specify an adjudication method (e.g., 2+1, 3+1). As stated above, the testing appears to be primarily technical and phantom-based, where ground truth is often objectively measurable through physical properties or established methods, rather than subjective expert interpretation requiring adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study was done or reported in this document. The submission focuses on demonstrating substantial equivalence of the updated CT system to its predicates through technical and non-clinical testing, not on measuring improvements in human reader performance with or without AI assistance.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
While the document focuses on the performance of the CT system and its software, it does not specifically describe a standalone algorithm-only performance study in the context of an AI/CADe device. The SOMARIS/7 syngo CT VB20 is a platform software update for CT scanners, enhancing system functionality and image reconstruction capabilities (e.g., "Enhanced FAST DE Results," "Precision Matrix," "DirectDensity™"). The "performance" being evaluated is the system's ability to generate cross-sectional images and support diagnostic tasks, as opposed to a specific AI algorithm. The performance evaluation discussed would inherently be of the "algorithm" integrated into the system, contributing to the overall image quality and functional capabilities.
7. Type of Ground Truth Used
The ground truth for the non-clinical testing appears to be based on:
- Physical Measurements and Phantom Readings: "Non-clinical test (integration and functional) including phantom tests were conducted." This implies that phantoms with known properties or simulated pathologies were used, and the system's output (image quality, dose metrics, etc.) was measured against these known values.
- Engineering Specifications / Reference Data: For software functional tests ("all software specifications have met the acceptance criteria"), the ground truth would be the defined engineering and design specifications for the software's intended behavior.
There is no mention of pathology, outcomes data, or expert consensus (in the typical sense of clinical ground truth for diagnostic accuracy) for establishing the ground truth described in this submission.
8. Sample Size for the Training Set
The document does not mention a training set sample size or the use of a separate training set. This is consistent with the nature of the submission, which describes a software update for a CT system rather than a machine learning or AI algorithm submission where training data sets are explicitly separated from test data. The software updates described are enhancements to the system's core functionality, reconstruction, and workflow, which are typically developed and verified through engineering processes rather than large-scale machine learning training.
9. How the Ground Truth for the Training Set Was Established
Since no training set is mentioned in the context of typical AI/ML development, this information is not applicable based on the provided document. The "training" for such system software updates primarily refers to the iterative development and internal testing processes by the engineers, where specifications serve as the "ground truth."
§ 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.