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.

Device Description

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.

AI/ML Overview

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.

Attribute	Cleared Device (K162393; K170751)	Device with Changes	Acceptance Criteria (Implied)	Reported Performance (Device with Changes)
Imaging Settings	1. PLAN2. POSITION3. 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	< 25 ppm over 450 mm DSV	(Not specified for "Device with Changes," implied "Same")	Maintain field homogeneity.	(Implied < 25 ppm over 450 mm DSV)
Field Stability	≤ 0.1 ppm/hr	(Not specified for "Device with Changes," implied "Same")	Maintain field stability.	(Implied ≤ 0.1 ppm/hr)
3D Imaging Volumes in cm	RL x AP x HFMin 20 x 27 x 29Max 54 x 48 x 54	(Not specified for "Device with Changes," implied "Same")	Maintain 3D imaging volume capabilities.	(Implied Same)
3D Imaging Resolution in cm	Min 0.075 x 0.075 x 0.15Max 0.3 x 0.3 x 0.3	(Not specified for "Device with Changes," implied "Same")	Maintain 3D imaging resolution.	(Implied Same)
2D Imaging Planes in cm	AP x HFMin. 27 x 27Max 45 x 350.35 x 0.35	(Not specified for "Device with Changes," implied "Same")	Maintain 2D imaging plane capabilities.	(Implied Same)
2D Imaging Resolution in cm	5, 7, or 10	Same	Maintain 2D imaging resolution.	Same
Geometric Accuracy	2 mm over 35 cm FOV1 mm over 20 cm FOV	(Not specified for "Device with Changes," implied "Same")	Maintain geometric accuracy.	(Implied Same)
Signal to Noise	30	(Not specified for "Device with Changes," implied "Same")	Maintain signal to noise ratio.	(Implied 30)
Temporal Integrity	0.01s or better	(Not specified for "Device with Changes," implied "Same")	Maintain temporal integrity.	(Implied 0.01s or better)
Imaging Pulse Sequences: T1, T2, DWI	Can be imported from an alternative imaging device.	Can be acquired by the proposed MRIdian Linac system or imported from an alternative imaging device.	The new system should be able to acquire these sequences directly in addition to importing them.	Device with changes can acquire these sequences. This is an enhancement, exceeding the predicate's capability in this specific aspect.
Imaging During Radiation Therapy Delivery	Single plane: 4 frames/secThree planes: 2 frames/secIn-plane resolution: 2.5 x 2.5 mm or less	Single plane: 8 frames/secThree planes: 2 frames/secIn-plane resolution: 2.5 x 2.5 mm or less	The new system should meet or exceed the predicate's imaging speed for critical functions.	Device with changes exceeds predicate with 8 frames/sec for single-plane imaging.
Localization/Positioning	3D volume, max 540x540x480 mm FOV, 3.0x3.0 mm or less in-plane resolution, <60s acquisition.	Same	Maintain localization/positioning capabilities.	Same
Planning Volumes	540x465x430 mm FOV, 1.5x1.5 mm or less in-plane resolution.	Same	Maintain planning volume capabilities.	Same
Multi-Channel RF System	Body coil SNR ≥ 12, Uniformity ≥ 60%12 Channel Torso Coil SNR ≥ 30 (Sagittal, Transversal), SNR ≥ 25 (Coronal), Uniformity ≥ 50%10 Channel Head/Neck Coil SNR ≥ 30 (Sagittal, Transversal), SNR ≥ 25 (Coronal), Uniformity ≥ 50%	Same with the addition of:4 Channel Head Coil SNR ≥ 30 (Sagittal, Transversal), SNR ≥ 25 (Coronal), Uniformity ≥ 50%	Maintain or enhance RF system performance.	Same, plus added 4 Channel Head Coil capability, enhancing coverage.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

The document primarily describes design verification testing and conformance to standards (e.g., IEC 60601-1, IEC 60601-2-33, IEC 62304). This implies testing was performed on:

The hardware and software components of the MRIdian Linac System with the proposed changes.
The testing would involve engineering tests, phantom studies, and possibly data from internal development/testing, rather than a "test set" of patient data in the context of diagnostic performance.
No information is provided on a "test set" of patient data, its sample size, or provenance. This is because the submission focuses on asserting technical equivalence and safety rather than a new clinical claim requiring a performance study on patient data.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

Not applicable/Not provided. Since this is a technical verification of an upgraded system rather than a new diagnostic algorithm, the concept of "experts establishing ground truth" for patient cases, as in an AI-driven image interpretation study, does not apply. The verification would involve engineers validating system specifications and output against known physical or simulated inputs.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

Not applicable/Not provided. Adjudication methods are relevant for studies where multiple human readers are evaluating cases and their interpretations need to be reconciled to establish a consensus ground truth. This type of study was not described.

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 MRMC comparative effectiveness study was mentioned or performed. This submission is not about evaluating a new AI assistant for human readers. It's about modifying an existing medical device's technical specifications and demonstrating that these modifications do not compromise safety or essential performance and maintain substantial equivalence to the predicate.

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

The document does not describe the evaluation of a standalone algorithm for diagnostic or therapeutic tasks. The MRIdian Linac System is an integrated system where imaging capabilities are part of the therapy delivery workflow, not a separate diagnostic algorithm. The changes enhance the imaging capabilities within this system.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)

Not explicitly described in terms of clinical ground truth. The "ground truth" for the verification testing would be the engineering specifications, performance standards (e.g., frame rate, resolution, field homogeneity), and safety requirements that the device's enhanced features were tested against. For example, a physics phantom might be used to verify image resolution or geometric accuracy.

8. The sample size for the training set

Not applicable/Not provided. This submission does not describe the development or training of a new AI algorithm that would require a "training set" of data.

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

Not applicable/Not provided. As there is no described training set for an AI algorithm, this information is not relevant to the document.

In summary:

This 510(k) submission (K181989) is primarily a technical modification submission for an existing medical device. Its purpose is to demonstrate that changes made to the MRIdian Linac System (specifically, enhanced imaging modalities, increased image reconstruction speed, and a condensed equipment footprint) maintain substantial equivalence to the predicate device (K162393; K170751) and comply with relevant safety and performance standards. The "acceptance criteria" are largely implied by the need to meet or exceed the predicate's technical specifications and adhere to recognized international standards for medical electrical equipment. No clinical performance study involving patient data, human readers, or AI algorithm evaluation is described.

Summary

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February 20, 2019

Image /page/0/Picture/1 description: The image contains the logos of the Department of Health and Human Services and the Food and Drug Administration (FDA). The Department of Health and Human Services logo is on the left, and the FDA logo is on the right. The FDA logo includes the letters "FDA" in a blue square, followed by the words "U.S. FOOD & DRUG ADMINISTRATION" in blue text.

ViewRay, Incorporated % Sean Delaney Sr. Director, Regulatory Affairs and Quality Assurance 815 E. Middlefield Road MOUNTAIN VIEW CA 94043

Re: K181989

Trade/Device Name: MRIdian Linac System Regulation Number: 21 CFR 892.5050 Regulation Name: Medical charged-particle radiation therapy system Regulatory Class: Class II Product Code: IYE, LNH Dated: January 22, 2019 Received: January 24, 2019

Dear Sean Delaney:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination. product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see

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https://www.fda.gov/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.htm); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Michael D. O'Hara

Robert Ochs, Ph.D. Director Division of Radiological Health Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K181989

Device Name MRIdian Linac System

Indications for Use (Describe)

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

Type of Use (Select one or both, as applicable):

☑ Prescription Use (Part 21 CFR 801 Subpart D)
☐ Over-The-Counter Use (21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

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Section 6: 510(k) Summary

The information below is provided for the modified MRIdian Linac system, following the format of 21 CFR 807.92.

Address and Contact Information: 1.

ViewRay Incorporated

815 East Middlefield Road

Mountain View, California, 94043

Contact Name: Sean A. Delaney

Phone: (650) 252-0969

Fax: (650) 625-9187

E-mail: sdelaney@viewray.com

Date Summary was prepared: July 13, 2017

Name of Device: MRIdian Linac System 2.

Trade/Proprietary Name: MRIdian Linac System

Common or Usual Name:

Accelerator, Linear, Medical;

System, Nuclear Magnetic Resonance Imaging

Regulation description/number:

21 CFR 892.5050

Device: Accelerator, Linear, Medical ●
Regulation Description: Medical charged-particle radiation therapy system .

21 CFR 892.1000

Device: System, Nuclear Magnetic Resonance Imaging ●
Requlation Description: Magnetic resonance diagnostic device .

Product Codes: IYE; LNH. Class II.

Device classification name: Accelerator, Linear, Medical; System, Nuclear Magnetic Resonance Imaging

3. Substantial Equivalence

Predicate device: MRIdian Linac System - K170751

Reference device: MRIdian Linac System - K162393

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Description of the Device 4.

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.
1. 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.

Intended Use Statement 5.

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Indication for Use Statement 6.

Substantial Equivalence 7.

ViewRay has demonstrated that the proposed MRIdian Linac system performs in a substantially equivalent manner to the predicate system (K162393; K170751).

Technological Characteristics 8.

The cleared MRIdian Linac system (K162393; K170751) is an Image-Guided Radiation Therapy System (IGRT) that uses a 6 MV linear accelerator radiotherapy system to deliver ionizing radiation while using a magnetic resonance imaging system (MRIS) unit for image guidance in real-time. The MRIdian Linac system has equivalent functionality when employing the proposed imaging modalities described in this submission.

Like the current MRIdian Linac system (K162393; K170751) the proposed system consists of three primary subsystems:

1. The Treatment Planning and Delivery System (TPDS, initially cleared under K102915) modified only to support the new user interface changes during use of the new MR sequences during treatment planning and delivery workflows and support treatment image reconstruction on updated Treatment Delivery Computer Unit (TDCU) computer hardware as a replacement for the 'Services' computer in the predicate device;
1. The Magnetic Resonance Imaging System (MRIS) which has been updated to include additional imaging pulse sequences; and
1. The Radiation Therapy Delivery System (RDS) modified only to condense the equipment room footprint by combining the pulse modulator, power distribution unit, and the linac control cabinet into one pulse modulator cabinet and to support the software interfaces changes described in this submission.

In both systems these three subsystems are designed to operate concurrently for accurate targeted administration of radiation therapy.

The MRIdian Linac system with the changes proposed in this section is otherwise unchanged and functions as designed in the original predicate system so that the imaging and radiotherapy fields of view coincide permitting imaging of the patient at the radiotherapy isocenter before and during treatment.

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The Treatment Planning and Delivery System (TPDS initial clearance K102915)

The Treatment Planning and Delivery System software (TPDS) is capable of assisting the clinician in creating treatment delivery and QA plans for the MRIdian Linac system. The TPDS includes clinician tasks for reviewing, prescribing, tracking, and correcting the course of patient treatment. The software system has two major roles: radiotherapy treatment planning, and radiotherapy treatment delivery.

ViewRay modified the TPDS user interface to support treatment planning and delivery workflows when using the new MR sequences and support treatment image reconstruction on updated the Treatment Delivery Computer Unit (TDCU) computer hardware. The TDCU replaces the Services computer used by the predicate MRIdian Linac system in order to gain efficiencies when reconstructing MR images. There have been no changes to the Monte Carlo dose calculation alqorithm. TPDS is otherwise unchanged from the predicate device (K162393; K170751) other than changes described in Section 12.

Magnetic Resonance Imaging System (MRIS)

The Maqnetic Resonance Imaging System (MRIS) unit incorporates an original equipment manufacturer (OEM) version of the Siemens MAGNETOM Avanto system combined with a 0.35T superconducting magnet, gradient coil, and radio frequency (RF) coil system, redesigned to be compatible with radiation therapy delivery. The MRIS system hardware remains unchanged from the current MRIdian Linac system (K162393; K170751).

The MRIS subsystem software has been updated to include additional imaging sequences described in Section 12. The MRIS software is otherwise unchanged from the predicate device (K162393; K170751).

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The Radiation Therapy Delivery System (RDS)

The Radiation Therapy Delivery System (RDS) of both the predicate MRIdian Linac system (K162393; K170751) and the proposed system described in this Section consist of a linear accelerator unit mounted on a ring gantry. By design, the radiation isocenter is in the middle of the imaqing field of view, permitting imaging at the radiotherapy isocenter before and during therapy. The RDS of both systems include:

Linear Accelerator;
. Gantry and Base Subsystem;
138-leaf Multi-leaf Collimator (MLC) (K170751); •
Patient Handling System;
Rotating Shim Gantry;
Radiation Therapy Control System (RTCS) and Console;
Magnetic and RF shielding sleeve technologies;
Linac Control Cabinet; and
. RF components required for linac functionality.

Equipment Room Update

ViewRay developed a revised design of the Pulse Modulator to reduce the physical footprint within the system equipment room by combining the pulse modulator, the Power Distribution Unit (PDU), and Linac Control Cabinet (LCC) into one cabinet. This change does not alter the performance of the system. Refer to Section 12 for details of this change.

The RDS is otherwise unchanged from the predicate device (K162393; K170751) except for modifications necessary to support software changes associated with the new options described in this section.

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The proposed MRIdian Linac system functions in a substantially equivalent manner to the predicate device when employing the new MR imaging modalities described in this submission. Table 6-1 presents a comparison of specifications for the predicate and proposed MRIdian Linac systems.

Table 6-1: Predicate Device Comparison Chart

Attribute	Cleared Device(K162393; K170751)	Device with Changes
Imaging Settings	1. PLAN—imaging for planning orvirtual simulation2. POSITION—imaging for patientpositioning3. TREAT—imaging for targetposition monitoring	Same
MR PhysicalCharacteristics:Bore Diameter	700 mm	Same
Spherical Volume(DSV)	500 mm
MRI Frequency	14.7 MHz
Field Strength	0.345 T
Field of View	500 mm	Same
FieldHomogeneity	< 25 ppm measured over 450 mmDSV
Field Stability	≤ 0.1 ppm/hr
3D ImagingVolumes in cm	RL x AP x HFMin 20 x 27 x 29Max 54 x 48 x 54
3D ImagingResolution in cm	Min 0.075 x 0.075 x 0.15Max 0.3 x 0.3 x 0.3
2D ImagingPlanes in cm	AP x HFMin. 27 x 27Max 45 x 350.35 x 0.35
2D ImagingResolution in cm	5,7, or 10	Same
GeometricAccuracy	2 mm over 35 cm FOV1 mm over 20 cm FOV
Signal to Noise	30
TemporalIntegrity	0.01s or better
Imaging Dose
Imaging PulseSequences:• T1 weighted• T2 weighted• DiffusionWeightedImaging(DWI)	Can be imported from analternative imaging device.	Can be acquired by the proposedMRIdian Linac system or importedfrom an alternative imaging device.
Imaging DuringRadiationTherapy Delivery	The MRI system supports theacquisition of a single plane (axial,sagittal, or coronal) in 4 frames persecond and up to three planes in 2frames per second with an in-planeresolution of 2.5 x 2.5 mm or less	The MRI system supports theacquisition of a single plane (axial,sagittal, or coronal) in 8 frames persecond and up to three planes in 2frames per second with an in-planeresolution of 2.5 x 2.5 mm or less
Localization/Positioning	The MRI system acquires andreconstructs a 3D volume forPositioning to a maximum of 540mm x 540 mm x 480 mm FOV withan in-plane resolution of 3.0 x 3.0mm or less. These volumes areacquired with an acquisition time ofless than 60 seconds.	Same
PlanningVolumes	540 mm x 465 mm x 430 mm FOVwith an in-plane resolution of 1.5 x1.5 mm or less.	Same
Multi-Channel RFSystem	Body coil SNR is ≥ 12; Uniformityis ≥ 60%12 Channel Torso Coil SNR is ≥ 30(Sagittal, Transversal); SNR is ≥25 (Coronal); Uniformity is ≥ 50%10 Channel Head/Neck Coil SNR is≥ 30 (Sagittal, Transversal); SNRis ≥ 25 (Coronal); Uniformity is ≥50%	Same with the addition of:4 Channel Head Coil SNR is ≥ 30(Sagittal, Transversal); SNR is ≥ 25(Coronal); Uniformity is ≥ 50%

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Summary of Performance Testing 9.

Design Verification testing was performed according to the FDA Quality System Regulation (21 CFR §820), ISO 13485 Quality Management System standard, ISO 14971 Risk Management Standard and the other FDA recognized consensus standards presented below.

The imaging capabilities of the proposed MRIdian Linac system showed substantial equivalence to the predicate system (K162393; K170751). Testing executed on the system verified conformance to design requirements and ensured all identified risks and hazards were mitigated, and demonstrated conformance to relevant safety standards. The MRIdian Linac system described in this premarket notification passed all verification testing, and the system conformed to all applicable sections of the standards presented below.

Software verification testing was conducted as recommended by FDA's Guidance for Industry and FDA Staff, "Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices." The MRIdian Linac software is considered as a "major" level of concern, since a failure or latent flaw in the software could directly result in serious injury or death to the patient or operator.

Electrical safety and electromagnetic compatibility (EMC) testinq were conducted on the MRIdian Linac system which verified the system complies with the IEC 60601-1-2 EMC standard and continues to meet IEC 60601-1 safety standards.

Name	Description
IEC 60601-1:2005 (ThirdEdition) + CORR. 1 (2006) +CORR. 2 (2007) + AM1(2012) ed. 3.1	Medical electrical equipment - Part 1: General requirements for basicsafety and essential performance
IEC 60601-1-2:2014 ed. 4.0	Medical electrical equipment - Part 1-2: General requirements for basicsafety and essential performance - Collateral Standard: Electromagneticdisturbances - Requirements and tests
IEC 60601-2-33: 2010 (ThirdEdition) + A1: 2013 + A2:2015 ed. 3.2	Medical electrical equipment - Part 2-33: Particular requirements for thebasic safety and essential performance of magnetic resonance equipmentfor medical diagnosis
IEC 60601-2-1:2009,AMD1:2014 2014 ed. 3.1	Medical electrical equipment - Part 2-1: Particular requirements for thebasic safety and essential performance of electron accelerators in therange 1 MeV to 50 MeV
IEC/EN 60976:2007 ed. 2.0	Medical electrical equipment - Medical electron accelerators - Functionalperformance characteristics
IEC 60601-1-6:2013 ed. 3.1	Medical electrical equipment - Part 1-6: General requirements for basicsafety and essential performance - Collateral standard: Usability
IEC 61217:2011 ed. 2.0	Radiotherapy Equipment - Coordinates, Movements & Scales
IEC 62083:2009 ed. 2.0	Medical electrical equipment - Requirements for the safety ofradiotherapy treatment planning systems
IEC 62304:2006 (FirstEdition) + A1:2015 ed. 1.1	Medical device software - Software life cycle processes
IEC 62366:2007, A1:2014 ed.1.1	Medical devices - Part 1: Application of usability engineering to medicaldevices
ISO 10993-1:2009 ed. 4.0	Biological evaluation of medical devices -- Part 1: Evaluation and testingwithin a risk management process

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10. Conclusion

Verification testing of the MRIdian Linac system with proposed enhance imaging modalities demonstrated that the device met established standards and design requirements. System performance was found to be substantially equivalent in function to the predicate device MRIdian Linac system (K162393; K170751). Therefore, the proposed MRIdian Linac system performs in a substantially equivalent manner as the predicate device when using the enhanced imaging modalities described in this submission.

Regulation Number and Section

§ 892.5050 Medical charged-particle radiation therapy system.

(a)
Identification. A medical charged-particle radiation therapy system is a device that produces by acceleration high energy charged particles (e.g., electrons and protons) intended for use in radiation therapy. This generic type of device may include signal analysis and display equipment, patient and equipment supports, treatment planning computer programs, component parts, and accessories.(b)
Classification. Class II. When intended for use as a quality control system, the film dosimetry system (film scanning system) included as an accessory to the device described in paragraph (a) of this section, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.