(99 days)
The syngo. CT Neuro Perfusion software package is designed to evaluate areas of brain perfusion. The software processes images or volumes that were reconstructed from continuously acquired CT data after the injection of contrast media. It generates the following result volumes:
- · Cerebral blood flow (CBF)
- Cerebral blood volume (CBV)
- · Local bolus timing (time to start (TTS), time to peak (TTP), time to drain (TTD))
- · Mean transit time (MTT)
- · Transit time to the center of the IRF (TMax)
- · Flow extraction product (permeability)
- · Temporal mip
- · Temporal average
- · Baseline volume
- Modified dynamic input data
The software also allows the calculation of mirrored regions or volumes of interest and the visual inspection of time attenuation curves. One clinical application is to visualize the apparent blood perfusion and the parameter mismatch in brain tissue affected by acute stroke.
Areas of decreased perfusion appear as areas of changed signal intensity:
- · Lower signal intensity for CBF and CBV
- · Higher signal intensity for TTP, TTD, MTT, and TMax
A second application is to visualize blood brain barrier disturbances by modeling extravascular leakage of blood into the interstitial space. This additional capability may improve the differential diagnosis of brain tumors and be helpful in therapy monitoring.
The syngo.CT Neuro Perfusion software allows the quantitative evaluation of dynamic CT data of the brain acquired during the injection of a compact bolus of iodinated contrast material. It mainly aids in the early differential diagnosis of acute ischemic stroke. The Blood-brain-barrier (BBB) imaging feature supports the diagnostic assessment of brain tumors.
By providing images of e.q. cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), and Mean Transit Time (MTT) from one set of dynamic CT images or volumes, syngo.CT Neuro Perfusion allows a quick and reliable assessment of the type and extent of cerebral perfusion disturbances, including fast evaluation of the tissue at risk and non-viable tissue in the brain. The underlying approaches for this application were cleared as part of the predicate device and remain unchanged in comparison to the predicate device.
syngo.CT Neuro Perfusion allows simultaneous multi-slice processing and supports the workflow requirements in a stroke workflow. The availability of flow extraction product imaging extends the option to the diagnosis of brain tumors. A listing of device modifications as part of the new software version VB20 of syngo.CT Neuro Perfusion is as follows:
- · Auto Stroke Workflow
(Calculation and display of the stroke results without user input) - . Rapid Results Technology (Calculates stroke results and quality control images without user input and sends all images to other DICOM nodes)
- Additional Parameters for Penumbra and Core Infarct Calculation
This software is designed to operate on at least the syngo.via VB20 hardware/software platform, and should be used with reconstructed images that meet the following minimum requirements:
- Images should be reconstructed with the high sampling frequency. Scan modes ● are e. g. adaptive 4D spiral, Dynamic sequence and dynamic multi-scan modes of Siemens CT scanners.
- A standard reconstruction kernel should be used
- . Images should be reconstructed with an increment smaller than the slice thickness to achieve good resolution
The provided text describes the syngo.CT Neuro Perfusion software, but it does not include a table of acceptance criteria with reported device performance or details of a specific comparative study. Instead, it focuses on demonstrating substantial equivalence to a predicate device through shared technological characteristics and general software verification and validation.
Here's a breakdown of the requested information based on the provided text, highlighting what is present and what is missing:
1. Table of Acceptance Criteria and Reported Device Performance
- Not provided. The document states that "The testing results support that all the software specifications have met the acceptance criteria" and "The results of these tests demonstrate that the subject device performs as intended." However, specific quantitative acceptance criteria or corresponding reported performance metrics are not given.
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Not provided. The document mentions "non-clinical tests" and "verification/validation testing" but does not specify the sample size of the test set (e.g., number of cases or patients) or the provenance (country of origin, retrospective/prospective nature) of any data used for testing.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not provided. There is no mention of experts being used to establish a ground truth for any test set. The document focuses on performance testing related to software functionality and specifications.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not provided. Since no expert review or ground truth establishment based on human readers is described, there is no mention of an adjudication method.
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 such study described. The document does not describe an MRMC comparative effectiveness study involving human readers or any effect size related to AI assistance. The focus is on the device's technical performance and its substantial equivalence to a predicate.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- Implied standalone testing, but not explicitly detailed. The "Non-Clinical Testing Summary" mentions "Performance tests were conducted to test the functionality of the syngo.CT Neuro Perfusion" and that "The results of these tests demonstrate that the subject device performs as intended." This suggests standalone testing of the algorithm's functionality, but the specifics of how this was measured (e.g., against what gold standard) for clinical parameters are not elaborated. The claims are focused on the software's ability to generate specific result volumes (CBF, CBV, TTP, etc.).
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- Not explicitly stated for clinical ground truth. The document does not specify a type of clinical ground truth (like pathology or outcomes data) used for comparing the device's generated parameters to a reference. The testing described appears to be primarily focused on verifying that the software's outputs are consistent with its design specifications and computational models, rather than an external clinical gold standard.
8. The sample size for the training set
- Not provided. The document describes performance testing in support of substantial equivalence and software verification/validation. It does not mention a training set or its sample size, indicating that this submission is not primarily based on a new AI model requiring training data. The underlying approaches are stated to be "unchanged in comparison to the predicate device."
9. How the ground truth for the training set was established
- Not applicable. As no training set is mentioned or implied for a new AI model, the method for establishing its ground truth is not discussed.
§ 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.