(28 days)
The Siemens Symbia series is intended for use by appropriately trained health care professionals to aid in detecting, localizing, diagnosing, staging of lesions, tumors, disease and organ function for the evaluation of diseases and disorders such as, but not limited to, cardiovascular disease, neurological disorders and cancer. The images produced by the system can also be used by the physician to aid in radiotherapy treatment planning and interventional radiology procedures.
SPECT: The SPECT component is intended to detect or image the distribution of radionuclides in the body or organ (physiology), using the following techniques: planar imaging, whole body imaging, and tomographic imaging for isotopes with energies up to 588 keV.
CT: The CT component is intended to produce cross-sectional images of the body by computer reconstruction of x-ray transmission data (anatomy) from either the same axial plane taken at different angles or spiral planes taken at different angles.
SPECT+CT: The SPECT and CT components used together acquire SPECT/CT images. The SPECT images can be corrected for attenuation with the CT images, and can be combined (image registration) to merge the patient's physiological (SPECT) and anatomical (CT) images.
Software: The syngo MI Applications software is a display and analysis package intended to aid the clinician in the assessment and quantification of pathologies in images produced from SPECT, PET, CT, and other imaging modalities.
The following statement applies only to Siemens Symbia Intevo 16, and Symbia Intevo Bold systems:
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 Siemens Symbia systems consist of Single Photon Emission Computed Tomography (SPECT) scanners and integrated hybrid X-Ray Computed Tomography (CT) and SPECT scanners. The SPECT subsystem images and measures the distribution of radiopharmaceuticals in humans for the purpose of determining various metabolic (molecular) and physiologic functions within the human body and integrates CT's anatomical detail for precise reference of the location of the metabolic activity. The CT component produces cross-sectional images of the body by computer reconstruction of X-Ray transmission data from either the same axial plane taken at different angles or spiral planes taken at different angles. The system can be used as an integrated SPECT and CT modality while also enabling independent functionality of SPECT and CT as stand-alone diagnostic imaging devices.
The provided text, K241898, describes a 510(k) premarket notification for Siemens Healthineers' Symbia SPECT and SPECT/CT Systems (Symbia VB23), which are updates to existing devices. The submission indicates that there are no significant changes to the fundamental technology or indications for use compared to the predicate device (Symbia 6.7 (VB22), K200474). Therefore, the provided text does not contain information about a study that proves the device meets specific acceptance criteria based on clinical performance metrics like sensitivity, specificity, or reader improvement.
Instead, the submission focuses on demonstrating substantial equivalence by highlighting that the core performance specifications of the SPECT detector and CT subsystem remain unchanged from the predicate device and that the updated system continues to comply with relevant safety and performance standards.
Here's an analysis of the information available in the document and a clear statement of what is not present regarding device performance studies:
What is present in the document:
- Acceptance Criteria (Implied / Compliance-based) and Reported Performance: The acceptance criteria are primarily implied through adherence to performance standards and regulations.
- CT Subsystem Performance: "Performance testing for the CT subsystem was included in the original premarket notification for the CT subsystems and there have been no changes affecting this testing. Each CT subsystem is tested and passes the Applicable Performance Standards prior to shipment." These standards include various parts of 21 CFR 1020.30, 21 CFR 1020.33, 21 CFR 1040.10, and 21 CFR 1040.11.
- SPECT Detector and Collimator Performance: "Collimator performance testing is conducted according to NEMA NU-1:2018. All Performance testing met the predetermined acceptance values." The "Detector Specifications" (Figure 2) and "Quantitative Accuracy Specifications" (Figure 3) list specific numerical values for intrinsic spatial resolution, energy resolution, flood field uniformity, count rate performance, system spatial resolution, system planar sensitivity, and quantitative error. These serve as the quantitative acceptance criteria for the SPECT component, and the document states: "The quantitative error for all isotopes with the collimators is smaller or equal to 10%, and met the predefined acceptance criteria."
- Software Validation: "Verification and validation of Siemens software is performed in accordance with documented procedures, test plans and specifications." This ensures functionality and quality.
Table of Acceptance Criteria and Reported Device Performance (as inferred from the document):
| Acceptance Criteria Category | Specific Criteria (if stated) | Reported Device Performance (if stated) |
|---|---|---|
| CT Subsystem Compliance | Adherence to 21 CFR 1020.30, 1020.33, 1040.10, 1040.11 | "Each CT subsystem is tested and passes the Applicable Performance Standards prior to shipment." "Performance testing performed on the CT subsystem is conducted in accordance with IEC 60601-2-44 and in accordance with US regulations including 21 CFR 1020.33, Computed Tomography (CT) equipment." (Unchanged from predicate) |
| SPECT Detector Specs (NEMA NU-1:2018) | Intrinsic Spatial Resolution (FWHM in CFOV) ≤3.8 mm | ≤3.8 mm (as per Figure 2) |
| Intrinsic Spatial Resolution (FWHM in UFOV) ≤3.9 mm | ≤3.9 mm (as per Figure 2) | |
| Intrinsic Energy Resolution (FWHM in CFOV) ≤9.9% | ≤9.9% (as per Figure 2) | |
| Intrinsic Flood Field Uniformity (Differential in CFOV) ≤2.5% | ≤2.5% (as per Figure 2) | |
| Multiple Window Spatial Registration ≤0.6 mm | ≤0.6 mm (as per Figure 2) | |
| Maximum Count Rate | 310 kcps (as per Figure 2) | |
| System Planar Sensitivity (LEHR at 10 cm) | 202 cpm/µCi (as per Figure 2) | |
| Quantitative Accuracy (NEMA & High Count Performance) | Quantitative error Tc99m LEHR/LPHR ≤10% | "smaller or equal to 10%, and met the predefined acceptance criteria." (as per Figure 3 and accompanying text) |
| Quantitative error I123 LPHR/MELP ≤10% | "smaller or equal to 10%, and met the predefined acceptance criteria." | |
| Quantitative error In111 MELP ≤10% | "smaller or equal to 10%, and met the predefined acceptance criteria." | |
| Quantitative error Lu177 MELP ≤10% | "smaller or equal to 10%, and met the predefined acceptance criteria." | |
| Quantitative error Lu177 MELP at 310kcps ≤10% | "smaller or equal to 10%, and met the predefined acceptance criteria." | |
| Quantitative error I131 HE ≤10% | "smaller or equal to 10%, and met the predefined acceptance criteria." | |
| General Safety and Effectiveness | Compliance with IEC 60601-1 series, 21 CFR 1020.30, 21 CFR 1020.33 | "Siemens Medical Solutions, USA Inc. adheres to recognized and established industry standards such as IEC 60601-1 series and 21 CFR 1020.30 and 21 CFR 1020.33 to minimize electrical, mechanical and radiation hazards." "Symbia VB23 conforms to applicable FDA recognized and international IEC, ISO and NEMA standards with regards to performance and safety as required by the respective SPECT FDA Guidance Documents." |
| Software Verification & Validation | Functionality meets specifications, quality adherence, risk mitigation implemented, appropriate specifications. | "Verification and validation of Siemens software is performed in accordance with documented procedures, test plans and specifications." "System and System Integration testing (validation) was carried out for all features of the project, and all planned test cases were executed." |
| Cybersecurity | Compliance with FDA Guidance for Medical Device Cybersecurity (Sept 2023) | "The Symbia systems' software has specific cybersecurity controls to prevent unauthorized access, modifications, misuse or denial of use. Additionally, controls are enabled to prevent the unauthorized use of information that is stored, accessed or transferred between the Symbia systems and external devices." |
Information NOT present in the document regarding a clinical performance study (e.g., for an AI/CAD algorithm):
The document does not describe a clinical study in the typical sense of evaluating the device's diagnostic performance (e.g., sensitivity, specificity, accuracy) using patient data with established ground truth. This is because the submission is for an updated version of an imaging system, not an AI/CAD software that provides diagnostic interpretations. The "syngo MI Applications software" is described as a "display and analysis package intended to aid the clinician," not as a tool that provides automated diagnostic outputs.
Therefore, the following points remain unaswered by the provided text:
- Sample size used for the test set and the data provenance: Not applicable as no clinical test set for diagnostic performance evaluation is mentioned. The performance testing described is likely phantom-based or engineering-level.
- Number of experts used to establish the ground truth for the test set and the qualifications of those experts: Not applicable. Ground truth for the system's physical performance is established by NEMA standards and engineering measurements, not clinical expert consensus.
- Adjudication method (e.g., 2+1, 3+1, none) for the test set: Not applicable.
- 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: Not applicable, as this device itself is not an AI/CAD system for diagnostic assistance, but an imaging scanner.
- If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: Not applicable.
- The type of ground truth used (expert consensus, pathology, outcomes data, etc.): For the performance testing cited (NEMA, CFR standards), the ground truth is established by the known physical properties of phantoms and calibrated measurement devices, ensuring the system outputs accurate measurements as per its specifications.
- The sample size for the training set: Not applicable. This is an imaging system, not a machine learning algorithm requiring a training set in the typical sense. Software "verification and validation" is mentioned to ensure functionality, which refers to standard software development lifecycle testing, not ML model training.
- How the ground truth for the training set was established: Not applicable.
In summary, the provided document details a 510(k) submission for a SPECT/CT imaging system update, focusing on demonstrating substantial equivalence to an existing predicate device and compliance with established performance standards and regulations rather than presenting a clinical performance study of a diagnostic AI algorithm.
§ 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.