(103 days)
The Siemens MR-PET system combines magnetic resonance diagnostic devices (MRDD) and Positron Emission Tomography (PET) scanners that provide registration and fusion of high resolution physiologic and anatomic information. acquired simultaneously and isocentrically. The combined system maintains independent functionality of the MR and PET devices, allowing for single modality MR and / or PET imaging.
These systems are intended to be utilized by appropriately trained health care professionals to aid in the detection, localization, and diagnosis of diseases and disorders.
The MR is intended to produce transverse, sagittal, coronal and oblique crossectional MR images, spectroscopic inages and/or spectra, and displays the internal structure and/or function of the human body. Other physical parameters derived from the images and or spectra may also be produced. Depending on the region of interest, approved contrast agents may be used, as described in their labeling. This system may also be used for imaging during interventional procedures when performed with MR compatible devices, such as MR safe biopsy needles.
The PET images and measures the distribution of PET radiopharmaceuticals in humans to aid the physician in determining various metabolic (molecular) and physiologic functions within the human body for evaluation of diseases and disorders such as, but not limited to, cardiovascular disease, neurological disorders and cancer.
The combined system utilizes the MR for radiation-free attenuation correction maps for PET studies. The system provides inherent anatomical reference for the fised PET and MR images due to precisely aligned MR and PET image coordinate systems.
The subject device, syngo MR E11P system software, is being introduced for the Biograph mMR system.
The syngo MR E11P SW includes new sequences, new features and minor modifications of already existing features. A high level summary of the new sequences and features is included below.
Migrated sequences and features from the previously cleared secondary predicate devices MAGNETOM Verio with syngo MR D13A and Siemens E-line Software with MAGNETOM Skyra with syngo MR E11C (K153343) are not described separately as these are commercially available and no changes are introduced for this system.
Improvement in Attenuation Correction
Atlas-based bones in u-map generation
The bone attenuation map is computed based on a reqular 4-compartment (air, lung, fat, water) segmentation from a Dixon sequence. As improvement, the bone information is added to these u-maps with a model-based bone segmentation algorithm using continuous linear attenuation coefficients (LACs) for bone to represent the variation in cortical bone density in different anatomical areas.
The model consists of the most relevant bones in the body torso in terms of overall attenuation. It consists of the skull, spine, pelvis and femur bone as individual components.
MR based FoV extension for attenuation correction - (HUGE)
In this SW version syngo MR E11P the attenuation map can be improved by using an optional MR-based FoV extension technique. This technique requires an additional MR measurement optimized for distortion reduced acquisition of the patient's arms resting along the body at the edge of the FoV.
New and Modified Features
Multimodal (Elastic) Motion Correction (BodyCOMPASS)
Elastic motion correction is introduced to reduce the effect of blur induced by respiratory motion during a PET acquisition. As a basic principle, periodic motion information is collected by means of the MR as a 4D image series and used for PET to
- . bin the PET counts into separate respiratory states
- provide a mapping for each spatial position and each respiratory state to a . reference state, which can be used in the PET reconstruction
Hence, the resulting PET image combines the advantages of a gated PET image with reduced motion blur while preserving the signal-to-noise ratio of static non-gated reconstruction.
Improvement in DIXON fat water separation
In this SW version syngo MR E11P the DIXON reconstruction technique (fat/water separation) is improved. The improved algorithm is based on global optimization and thus minimizes the probability of local fat/water swaps where part of water image is wrongly assigned to fat image and/or vice versa.
Dot Cockpit (DotGO), including PET Workflow
The previously cleared DotGO with the Dot Cockpit and the MR only Dot Engines is now available on the Biograph mMR with syngo MR E11P. The configuration of PET workflows is now integrated into the Dot Cockpit for higher productivity.
This modification increases the robustness and usability for the clinical workflow with the new PET Planning Group. PET Planning Step and special reduced MR Parameter cards while still offering the full parameter access with detail views, PET and AC specific steps with their parameter cards.
Improved MR PET Workflow
With the software syngo MR E11P a set of protocols are included in order to run a clinical whole body workflow with 5 beds, AC, T1-, T2-, DWI-contrast, adjustments and SAR pauses in 45 minutes.
In this workflow the AC protocol is acquired in high resolution (1.3 mm * 1.3mm in plane) using CAIPIRINHA acceleration. Alternatively, an AC protocol in conventional resolution (2.6 mm * 2.6 mm in plane) using CAIPIRINHA acceleration is available in order to reduce the acquisition time for AC measurement in case T1-contrast is not requested from AC scan.
Other Software Improvements
NEMA NU 2:2012
As it is possible that routine NEMA testing may be required to retain ACR accreditation, Siemens has developed an optional software package which enables a Biograph mMR system user to quantify image quality for certain performances according to the most recent available NEMA standards.
Improvements in Retro Recon Task Card
In the RetroRecon Task Card of the Biograph mMR with syngo MR E11P, an additional identifier in the list of the parameter Attenuation Correction indicates gated u-Maps.
Furthermore a Tooltip for the Attenuation Correction parameter explains the identifier.
For respiratory gating a new Respiratory Curve Display shows the recorded cushion signal as well as the specified gates for some gating types.
Third Party Interface for AC
An Interface functionality is added to the synqo MR E11P software to import attenuation maps of third party components for hardware attenuation correction.
Other Modifications
Front Cover Panel Refresh for Biograph mMR
The Biograph mMR with syngo MR E11P will receive new system covers. The graphic design of the cover has been changed to give the systems an updated and more modern look to highlight the introduction of a new software version.
MaRS - technology for Biograph mMR
The modified control system of the Biograph mMR integrates the functions of the AMC (Advanced Measurement Control) and MRIR (MR Image Reconstructor) into one computer called MaRS (Measurement and Reconstruction System).
The MaRS system performs sequence control and image reconstruction without additional MRIR. The introduction of the MaRS was part of the secondary predicate device MAGNETOM Verio with syngo MR D13A (K121434). This is now updated to new computer hardware with this submission.
Physiological Monitoring Unit (PMU)
The Physiological Measurement Unit (PMU) was modified to improve the accuracy of triggers on the respiration signal. The PMU provides ECG, respiration and peripheral pulse as well as external trigger input to control of the MR imaging sequences for synchronization.
Syngo MR Software Features
Other features were included unchanged from the secondary predicate devices (K121434 and K153343). These features expand the Biograph mMR's MR scanning capabilities and update the feature set to be more similar to currently released Siemens MR software.
Acceptance Criteria and Device Performance for Biograph mMR with syngo MR E11P system software (K163234)
Based on the provided FDA 510(k) summary, the acceptance criteria and supporting studies focus on demonstrating that the new syngo MR E11P software for the Biograph mMR system maintains the safety and effectiveness of the predicate device while introducing improvements and new features. The document highlights the substantial equivalence argument, rather than providing explicit numeric acceptance criteria and performance tables for specific clinical tasks. However, we can infer the performance goals and the studies conducted to support them.
1. Table of Acceptance Criteria and Reported Device Performance
As explicit numeric acceptance criteria and a detailed performance table are not provided in the 510(k) summary, the table below represents the implied acceptance criteria (based on the device's intended use and the nature of the modifications) and the general results reported for demonstrating substantial equivalence.
| Feature/Area of Improvement | Implied Acceptance Criteria (Performance Goal) | Reported Device Performance (General Results) |
|---|---|---|
| New Sequences & Features | Equivalent or improved diagnostic performance compared to predicate in terms of image quality and clinical utility. | Sample clinical images taken for particular new and modified sequences demonstrated performance as intended. Image quality assessments of all new/modified sequences and algorithms were completed with satisfactory results, indicating performance as intended. |
| Attenuation Correction (Atlas-based bones in u-map generation) | Accurate and reliable bone attenuation maps for PET studies, minimizing artifacts and improving quantitative accuracy compared to previous 4-compartment segmentation. | Quantitative comparison study of attenuation maps of CT-based AC and MR-based AC method for whole-body PET/MR imaging combining Dixon-based soft-tissue segmentation and model-based bone estimation was conducted. While specific metrics are not given, the study supports the substantial equivalence, implying acceptable performance. |
| Attenuation Correction (MR based FoV extension - HUGE) | Accurate attenuation maps for extended FoV, accommodating patient anatomy (e.g., arms by the body) without truncation artifacts, comparable to established PET-based FoV extension. | Comparison study of an extended MR FoV and truncation correction (HUGE) with truncated data without FoV extension and additionally to an established approach of PET-based FoV extension was performed. The study supports the substantial equivalence, implying acceptable performance and comparable results to the reference. |
| Quantitative SUV Estimation with MR-based AC | Accurate and consistent SUV estimations using new MR-based AC methods, comparable to reference CT AC. | Quantitative comparison study of SUV estimation for MR-based AC methods to a reference CT AC comparing: standard Dixon 4-compartment segmentation alone, Dixon with a superimposed model-based bone compartment, and Dixon with a superimposed bone compartment and linear attenuation correction optimized specifically for brain tissue was conducted. The study results are cited as supportive of substantial equivalence, indicating acceptable SUV estimation performance for the new methods. |
| Multimodal (Elastic) Motion Correction (BodyCOMPASS) | Effective reduction of motion blur in PET images while preserving signal-to-noise ratio, improving image quality for diagnosis. | The feature aims to combine advantages of gated PET with reduced motion blur while preserving SNR of static non-gated reconstruction. Clinical images were provided to support substantial equivalence for this new software feature, implying successful demonstration of its intended effect. |
| Improved DIXON fat water separation | Minimized probability of local fat/water swaps, leading to more accurate and robust fat/water separation. | The improved algorithm is based on global optimization to minimize local fat/water swaps. Clinical images were provided to support substantial equivalence for this new software feature, implying successful demonstration of its intended effect. |
| General Software Performance (Workflow, Usability, Robustness) | Improved clinical workflow, reduced complexity, increased productivity, and enhanced usability. | The Dot Cockpit (DotGO) with PET workflow integration, improved MR PET workflow, and other software improvements are stated to increase robustness and usability, improve user workflow, and reduce complexity. These are qualitative improvements for which successful implementation and user experience (implied from V&V and clinical images) serve as evidence. |
| Safety and Compliance | Compliance with recognized medical device standards and risk management requirements. | Software verification and validation testing completed in accordance with FDA guidance. Risk management (ISO 14971:2007) was performed with mitigation measures. Conforms to IEC 62304:2006, IEC, and NEMA standards, as well as the FDA Guidance for MR Diagnostic Devices. |
2. Sample size used for the test set and the data provenance:
- Test Set Sample Size: The document does not explicitly state the numerical sample size (e.g., number of patients, cases) for the clinical images used in the comparison studies. It mentions "Sample clinical images were taken for particular new and modified sequences" and "Additionally clinical images were provided to support the substantial equivalence for the new software features of the subject device." The quantitative comparison studies also imply a dataset, but the size is not specified.
- Data Provenance: The provenance of the data (country of origin, retrospective/prospective) is not explicitly detailed. The manufacturer is Siemens Healthcare GmbH based in Erlangen, Germany, and Siemens Medical Solutions USA, Inc. is the establishment in the USA. It is common for such validation studies to involve data from internal research or collaborating institutions, but the document does not specify. The nature of "clinical images" and "quantitative comparison studies" suggests real patient data, likely retrospective or a mix, but this is not confirmed.
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 summary. While clinical images and quantitative comparisons were performed, the method of establishing ground truth and the involvement and qualifications of experts for defining "ground truth" are not described. It's likely that in the context of imaging system performance, "ground truth" for image quality and diagnostic accuracy would implicitly rely on expert assessment, but the details are omitted.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
This information is not provided in the summary. Without details on expert involvement in ground truth establishment, no adjudication method can be inferred.
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:
A multi-reader multi-case (MRMC) comparative effectiveness study focusing on the improvement of human readers with AI assistance was not explicitly described in this 510(k) summary. The document describes improvements to the imaging system's software components (e.g., attenuation correction, motion correction, fat/water separation) that likely improve image quality and potentially diagnostic accuracy, but it doesn't quantify reader performance improvement with "AI assistance" in the sense of a decision support system. The listed studies are more focused on the technical performance and quantitative accuracy of the imaging system's outputs.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
Yes, a form of standalone performance assessment was conducted for many of the technical improvements. The "Nonclinical Tests" section details:
- "Image quality assessments of all new/modified sequences and algorithms, were completed."
- The "Clinical Tests" section describes "Quantitative comparison study of attenuation maps of CT-based AC and MR-based AC method..." and "Quantitative comparison study of SUV estimation for MR-based AC methods..." These are direct technical evaluations of the algorithm's output (image quality, quantitative accuracy) independent of a human reader's diagnostic performance.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
The type of ground truth used varies based on the specific study:
- For attenuation correction and SUV estimation studies: The ground truth appears to be established by comparison to established methods, specifically "reference CT AC." This implies that CT attenuation maps are considered the gold standard for comparison in these contexts.
- For general image quality and new feature performance: The "ground truth" is likely based on visual assessment by experts (implied, though not stated) combined with quantitative metrics relevant to image quality (e.g., minimizing motion blur, reducing fat/water swaps) derived from predefined technical standards or expected outcomes.
8. The sample size for the training set:
This information is not provided in the summary. The document describes modifications and improvements to existing software components and introduces new sequences and features. While these often involve internal development and testing cycles that might use various datasets, specific training set sizes for machine learning components (if any, beyond the "atlas-based bones" model) are not detailed.
9. How the ground truth for the training set was established:
This information is not provided in the summary. Given the nature of the improvements (e.g., atlas-based bone models, global optimization for Dixon), it's likely that internal reference datasets and expert knowledge were used, but the specifics of their ground truth establishment are not disclosed. For the "atlas-based bones in u-map generation," the "model consists of the most relevant bones in the body torso" which implies a pre-defined anatomical model or a training process that derived this model from a dataset with defined bone attenuation properties. However, details are absent.
§ 892.1200 Emission computed tomography system.
(a)
Identification. An emission computed tomography system is a device intended to detect the location and distribution of gamma ray- and positron-emitting radionuclides in the body and produce cross-sectional images through computer reconstruction of the data. This generic type of device may include signal analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component parts, and accessories.(b)
Classification. Class II.