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The MRIdian Linac system, with magnetic resonance imaging capabilities, is intended to provide stereotactic radiosurgery and precision radiotherapy for lesions, tumors, and conditions anywhere in the body where radiation treatment is indicated.

The MRIdian Linac system is an image-quided radiation therapy (IGRT) system that uses a 6 MV linear accelerator radiotherapy system to deliver ionizing radiation while using a magnetic resonance imaging system for image guidance in real time. The MRIdian consists of the Treatment Planning and Delivery System (TPDS), Magnetic Resonance Imaging System (MRIS) and the Radiation Therapy Delivery System (RDS). These three subsystems are designed to operate concurrently for accurate targeted administration of radiation therapy.

The provided text is a 510(k) summary for the MRIdian Linac System. It outlines the device's technical specifications, intended use, and its comparison to a predicate device to establish substantial equivalence. However, it does not contain acceptance criteria, reported device performance figures, or details of a study (like sample size, data provenance, expert ground truth, adjudication methods, MRMC studies, or standalone performance) that would typically be used to prove a device meets specific acceptance criteria related to a new functionality or performance claim.

Instead, this document focuses on demonstrating that the modified MRIdian Linac System is substantially equivalent to its predicate device based on:

• Identical Intended Use and Indications for Use.
• Substantially equivalent technological characteristics, with minor differences that do not raise new questions of safety or effectiveness.
• Conformance to design specifications and satisfaction of intended users' needs, including risk mitigations.
• Compliance with various regulatory and recognized standards (e.g., medical electrical equipment safety, electromagnetic compatibility, software life cycle, usability, biocompatibility).

The document states: "Test results demonstrate that the device conforms to design specifications and meets the needs of the intended users, including assuring risk mitigations were implemented and functioned properly. Software testing was performed and documented as recommended by FDA's Guidance for Industry and FDA Staff, "Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices."" This implies that internal verification and validation testing was conducted, but the specific acceptance criteria and the detailed results of these tests are not provided in this public summary.

Therefore, I cannot extract the requested information regarding detailed acceptance criteria and a study proving those criteria are met from the provided text in the format you specified. The document focuses on demonstrating substantial equivalence to a predicate device rather than presenting a performance study with explicit acceptance metrics for a novel AI or diagnostic functionality.

The closest information related to performance that is provided is in the "Summary of Technological Characteristics" table, which compares various physical and imaging parameters of the subject device to the predicate device. This table effectively shows that the characteristics are either "Same" or have minor, non-significant differences (e.g., spatial resolution for volume scans and cine scans).

If this were a submission for a new AI feature, the acceptance criteria would typically involve metrics like sensitivity, specificity, AUC, and the study details would describe how these were measured against a ground truth. None of that is present here.

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The MRIdian Linac system, with magnetic resonance imaging capabilities, is intended to provide stereotactic radiosurgery and precision radiotherapy for lesions, tumors, and conditions anywhere radiation treatment is indicated.

The MRIdian Linac system (K162393; K170751) delivers ionizing radiation using a magnetic resonance imaging system (MRIS) unit for image guidance. This submission describes an optional change only to the treatment planning and delivery imaging workflows of the predicate MRIdian Linac system. ViewRay developed the following additional imaging modalities for use during MRIdian Linac system treatment planning and delivery workflows: 1. Introduction of a Treatment Delivery Computer Unit (TDCU) to increase treatment imaging reconstruction and display speed in excess of eight frames per second along with improved cine image resolution used for target tracking. 2. The predicate MRIdian Linac system supports the import of MR images obtained from a separate imaging system for use in treatment planning. In addition to importing additional MR images, the proposed MRIdian Linac system is also able to generate the following additional MR sequences for use during planning, positioning, and treatment delivery workflows: a. Turbo Spin Echo (TSE) pulse sequence family including Half Fourier Acquisition Single Shot Turbo Spin Echo (HASTE) and Diffusion Prepared Turbo Spin Echo (DP-TSE) which enables the following contrast protocols: i. T1-weighted (spin-lattice; magnetization in the same direction as the static magnetic field); ii. T2-weighted (spin-spin; magnetization transverse to the static magnetic field); and iii. Diffusion-Weighted Imaging (DWI) with ability to generate Apparent Diffusion Coefficient (ADC) maps to overlay and register to other images. b. True Fast Imaging (TRUFI) pulse sequence with radial sampling enabling higher speed imaging during treatment delivery. The currently marketed MRIdian Linac system integrates radiation therapy with simultaneous magnetic resonance imaging of soft tissues to provide optimal alignment, adaptation, and tracking. These proposed changes to the existing system described in this section aim to improve MR imaging speed and quality and provide additional image contrast modalities.

The provided text describes modifications to an existing MRIdian Linac System (K162393; K170751) and seeks to demonstrate substantial equivalence to the predicate device. However, it does not contain explicit acceptance criteria or a detailed study proving the device meets those criteria in the typical sense of a clinical performance study with human readers and ground truth for diagnostic accuracy.

Instead, the document focuses on technical equivalence and verification testing to ensure the new imaging modalities and hardware/software changes do not negatively impact the system's performance and meet safety and quality standards, making it substantially equivalent to the cleared predicate device.

Here's an analysis based on the information provided, highlighting what is present and what is absent:

1. A table of acceptance criteria and the reported device performance

The document provides a "Predicate Device Comparison Chart" (Table 6-1 on page 8) which compares various technical attributes of the cleared device with the device with changes. While these are not framed as "acceptance criteria" in the sense of a clinical performance study (e.g., sensitivity, specificity), they represent the technical performance metrics that were likely considered in verifying equivalence.

2. POSITION
3. TREAT | Same | Maintain existing imaging settings and functionality. | Same |
   | MR Physical Characteristics: Bore Diameter | 700 mm | Same | Maintain physical dimensions. | Same |
   | Spherical Volume (DSV) | 500 mm | (Not specified for "Device with Changes," implied "Same") | Maintain diagnostic spherical volume. | (Implied 500 mm) |
   | MRI Frequency | 14.7 MHz | (Not specified for "Device with Changes," implied "Same") | Maintain MRI frequency. | (Implied 14.7 MHz) |
   | Field Strength | 0.345 T | (Not specified for "Device with Changes," implied "Same") | Maintain field strength. | (Implied 0.345 T) |
   | Field of View | 500 mm | Same | Maintain field of view. | Same |
   | Field Homogeneity |

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The MRIdian Linac system, with magnetic resonance imaging capabilities, is intended to provide stereotactic radiosurgery and precision radiotherapy for lesions, tumors, and conditions anywhere in the body where radiation treatment is indicated.

This submission describes a modification to the currently marketed multi-leaf collimator (MLC) cleared as part of the MRIdian Linac system (K162393) intended to enhance beam resolution. The current MLC is comprised of 60 tungsten leaves in two opposing 30-leaf banks. The design modification discussed in this submission essentially divides the two existing leaf banks in half splitting them along the leaf motion direction and shifting the banks by one half of a leaf width. The "tonque and groove" is eliminated from the leaves and the shifted banks act effectively as better focused "tongue and groove" mechanism. As with the predicate, each MLC layer of the modified MLC is focused to a point beyond the source point of the Linac radiation to improve interleaf leakage performance. In this system, the focus point is 15 mm further away than the source point. The minimum projected leaf width then becomes one half the physical projected leaf width. The projected leaf width is 8.3 mm and the projected half leaf width is 4.15 mm. The modified MLC design has two layers of opposing tungsten leaves; the top and bottom layers have 34 and 35 leaves in each bank respectively for a total of 138 leaves. There have been no other changes to the cleared MRIdian Linac system (K162393).

My apologies. I cannot fulfill this request. The provided text is a US FDA 510(k) Premarket Notification document, which primarily focuses on demonstrating substantial equivalence of a modified medical device (MRIdian Linac System with 138-leaf Collimator) to a legally marketed predicate device (MRIdian Linac System with 60-leaf Collimator).

The document does not describe an AI/ML-driven device or study parameters typical for such devices, such as:

• Acceptance criteria related to AI performance metrics (e.g., sensitivity, specificity, AUC)
• Sample sizes for test sets in the context of AI model evaluation (e.g., number of images, patients)
• Data provenance for AI model training or testing (e.g., retrospective vs. prospective data cohorts, country of origin)
• Expert involvement in establishing ground truth for AI model testing
• Adjudication methods for AI performance evaluation
• MRMC comparative effectiveness studies with AI assistance
• Standalone AI algorithm performance studies
• Ground truth types specific to AI applications (e.g., pathology reports, long-term outcomes)
• Training set details for AI models

Instead, the document focuses on:

• Changes to a hardware component: The modification is to the Multi-Leaf Collimator (MLC), specifically increasing the number of leaves from 60 to 138 to improve beam resolution.
• Engineering and Safety Testing: The "Summary of Performance Testing" section details various IEC and ISO standards for electrical safety, EMC, usability, software lifecycle, and general medical device performance, verifying that the modified hardware system still meets these standards.
• Substantial Equivalence Argument: The core of the 510(k) is to show that despite the MLC change, the device's fundamental functionality and safety remain equivalent to the predicate.

Therefore, I cannot extract the requested information about AI model acceptance criteria and study design from this document because it is about a hardware modification to a radiation therapy system, not an AI/ML medical device.

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