Search Results

The GSI Viewer accepts images from a CT System that can acquire CT images using different kV levels of the same anatomical region of a patient in a single rotation from a single source. The differences in the energy dependence of the attenuation coefficient of the different materials provide information about the chemical composition of body materials. This approach enables images to be generated at energies selected from the available spectrum to visualize and analyze information about anatomical and pathological structures.

GSI provides information of the chemical composition of renal calculi by calculation and graphical display of the spectrum of effective atomic number. GSI Kidney stone characterization provides additional information to aid in the characterization of uric acid versus non-uric acid stones. It is intended to be used as an adjunct to current standard methods for evaluating stone etiology and composition.

The GSI Viewer with VUE option employs the same technology as the Technology: that of the GSI Viewer on its predicate device.

The GSI Viewer accepts images from a CT System that can acquire CT images using different kV levels of the same anatomical region of a patient in a single rotation from a single source. The differences in the energy dependence of the attenuation coefficient of the different materials provide information about the chemical composition of body materials. This approach enables images to be generated at energies selected from the available spectrum to visualize and analyze information about anatomical and pathological structures.

GSI provides information of the chemical composition of renal calculi by calculation and graphical display of the spectrum of effective atomic number. GSI Kidney stone characterization provides additional information to aid in the characterization of uric acid versus non-uric acid stones. It is intended to be used on non-contrast studies as an adjunct to current standard methods for evaluating stone etiology and composition.

The unmodified device Discovery CT750 HD (K120833) offers the Gemstone Spectral Imaging (GSI) capability that uses rapid kV switching to acquire the dual energy samples almost simultaneously. This enables generation of material density data that can be used for the separation of materials and derivation of monochromatic spectral images using a projection based reconstruction algorithm.

GSI Viewer is a post processing visualization tool on the Discovery CT750 HD system that allows users to view and process spectral images acquired by the GSI scan modes. It allows for the review of monochromatic energy images at user selectable energy levels, detailed analysis using material decomposed images (such as water-iodine, water calcium, etc.), and complementary information using the Effective-Z images by providing an estimate of the protons' effective atomic number in a voxel.

The modification being introduced is the VUE (Virtual Unenhanced Exam) option that produces a material suppressed image at a given monochromatic energy in the conventional CT Hounsfield Units.

This modification is based on the existing capability of the predicate device that generates material separated images in the Material density (MD) space and is the subject of this pre-market notification.

The provided 510(k) summary for the GE Healthcare GSI Viewer with VUE Option does not include a study that proves the device meets specific acceptance criteria related to its performance.

Instead, the submission states that:

• The device did not require clinical studies to support substantial equivalence.
• GE Healthcare considers the device to be as safe, as effective, and its performance substantially equivalent to the predicate device.

Therefore, many of the requested details cannot be extracted from this document, as a performance study with defined acceptance criteria was not conducted or reported in this summary.

Here's a breakdown of the specific points based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

Not applicable. The document explicitly states: "The subject of this premarket submission, GSI Viewer with VUE option, did not require clinical studies to support substantial equivalence." Therefore, no specific acceptance criteria for performance and no reported performance metrics for these criteria are provided.

2. Sample size used for the test set and the data provenance

Not applicable. No clinical or performance study involving a test set was reported as part of this 510(k) summary.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

Not applicable. No ground truth establishment activity was reported, as no clinical or performance study was conducted.

4. Adjudication method for the test set

Not applicable. No test set adjudication method was reported, as no clinical or performance study was conducted.

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

Not applicable. An MRMC comparative effectiveness study was not done. The device description indicates it's a "post processing visualization tool" and a "material suppressed image" option, rather than an AI-assisted diagnostic tool designed to directly improve human reader performance. No human-in-the-loop performance improvement data is provided.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

Not applicable. No standalone performance study was reported. The device is described as a "GSI Viewer" and an "Option" within an existing viewing system, performing "generation of material density data" and "material suppressed images." No algorithm-only performance metrics were provided.

7. The type of ground truth used

Not applicable. No clinical or performance study requiring ground truth was reported.

8. The sample size for the training set

Not applicable. The document does not describe the development of a machine learning or AI model that would typically require a training set. The modification "is based on the existing capability of the predicate device that generates material separated images in the Material density (MD) space." This suggests an algorithmic modification rather than a data-driven model.

9. How the ground truth for the training set was established

Not applicable. As no training set was reported (see point 8), there is no information on how its ground truth might have been established.

Summary of what was done instead of a performance study:

The submission focuses on demonstrating substantial equivalence to a predicate device (K120833 Discovery CT750 HD) based on:

• The GSI Viewer with VUE Option employing the "same technology" as the GSI Viewer on its predicate device.
• Compliance with voluntary standards.
• Application of standard quality assurance measures during development: Risk Analysis, Requirements Reviews, Design Reviews, Performance testing (Verification), Safety testing (Verification), and Final acceptance testing (Validation). (Note: "Performance testing (Verification)" and "Final acceptance testing (Validation)" here refer to engineering/software testing against functional requirements, not clinical performance against acceptance criteria in a comparative study).

Ask a specific question about this device