Motion Tracking and Compensation Feature for the Radixact Treatment Delivery System

K182687 · Accuray Incorporated · IYE · Nov 23, 2018 · Radiology

Device Facts

• Record ID: K182687
• Device Name: Motion Tracking and Compensation Feature for the Radixact Treatment Delivery System
• Applicant: Accuray Incorporated
• Product Code: IYE · Radiology
• Decision Date: Nov 23, 2018
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 892.5050
• Device Class: Class 2
• Attributes: Therapeutic

Intended Use

The Motion Tracking and Compensation Feature is an option within the intended use of the Radixact Treatment Delivery System. The Radixact Treatment Delivery System is intended to be used for the delivery of radiation therapy, stereotactic radiotherapy or stereotactic radiosurgery to tumors or other targeted tissues. The megavoltage x-ray radiation is delivered using rotational, non-rotational, intensity modulated (IMRT), or non-modulated (non-IMRT/three dimensional conformal) treatment techniques and using image-guided (IGRT) or non-image-guided workflows in accordance with the physician approved plan.

Device Story

Motion Tracking and Compensation Feature is an add-on for the Radixact Treatment Delivery System; enables real-time tumor motion management during radiation therapy. System inputs include images from a kV imaging subsystem and respiration amplitude data from a tracking device (Synchrony). Device transforms inputs to predict tumor location; adjusts radiation beam delivery in real-time via multi-leaf collimator (MLC) and jaw movements to compensate for motion. Used in clinical radiation oncology settings; operated by trained medical staff. Output consists of dynamic beam repointing to maintain target coverage during respiration. Benefits include improved precision in targeting moving tumors, potentially sparing healthy tissue. Does not provide diagnosis or treatment recommendations.

Clinical Evidence

Bench testing only. No clinical or animal data required. Verification and validation testing confirmed compliance with applicable FDA-recognized consensus safety standards for radiation therapy equipment and design specifications.

Technological Characteristics

System includes kV imaging subsystem (50-150 kV X-ray tube, 0.6-1.0 mm focal spot) and motion management software. Radiation source: 6 MV standing wave accelerator with magnetron. Collimation: primary, jaws, and MLC. Connectivity: standalone radiation delivery system. Safety: integrated interlocks, transformer isolation, UPS for data backup. Software: embedded controls subsystem (ECS) for radiation delivery and positioning.

Indications for Use

Indicated for the delivery of radiation therapy, stereotactic radiotherapy or stereotactic radiosurgery to tumors or other targeted tissues anywhere in the body under the direction of a licensed medical practitioner.

Regulatory Classification

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.

Predicate Devices

• Radixact Treatment Delivery System (K161146)

Reference Devices

• Synchrony Respiratory Tracking System (K120233)

Submission Summary (Full Text)

{0}------------------------------------------------

Image /page/0/Picture/0 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which consists of a blue square with the letters "FDA" in white, followed by the words "U.S. FOOD & DRUG" in blue, and the word "ADMINISTRATION" in a smaller font size below it.

November 23, 2018

Accuray Incorporated % Keith Picker Senior Regulatory Affairs Specialist 1240 Deming Way MADISON WI 53717

Re: K182687

Trade/Device Name: Motion Tracking and Compensation Feature for the Radixact Treatment Delivery System Regulation Number: 21 CFR 892.5050 Regulation Name: Medical charged-particle radiation therapy system Regulatory Class: Class II Product Code: IYE Dated: September 25, 2018 Received: September 26, 2018

Dear Mr. Picker:

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 mav, 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 avare 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

{1}------------------------------------------------

requirements, including, but not limited to: registration and listing (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 https://www.fda.gov/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.html; good manufacturing practice requirements as set forth in the quality systems (OS) 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 mediation-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 ([e-mail]) or phone [phone] or 301-796-7100).

Sincerely.

Michael D. O'Hara For

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

Enclosure

{2}------------------------------------------------

# Indications for Use

510(k) Number (if known) K182687

#### Device Name

Motion Tracking and Compensation Feature for the Radixact Treatment Delivery System

Indications for Use (Describe)

The Motion Tracking and Compensation Feature is an option within the indications for use of the Radixact Treatment Delivery System. The Radixact Treatment Delivery System is indicated for the delivery of radiation therapy, stereotactic radiotherapy or stereotactic radiosurgery to tumors or other targeted tissues anywhere in the direction of a licensed medical practitioner.

| Type of Use (Select one or both, as applicable) | |
|-----------------------------------------------------------------|----------------------------------------------------------------|
| <span> Prescription Use (Part 21 CFR 801 Subpart D) </span> | <span> Over-The-Counter Use (21 CFR 801 Subpart C) </span> |

#### CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

#### *DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.*

The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

> Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff [e-mail]

"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."

{3}------------------------------------------------

Image /page/3/Picture/1 description: The image shows the Accuray logo. The logo consists of a stylized graphic on the left and the word "ACCURAY" in blue text on the right. The graphic is made up of three curved lines in green, purple, and blue. The word "ACCURAY" is in a sans-serif font, and there is a registered trademark symbol after the word.

#### Section 8 510(k) Summary

## Submitter

| Accuray Incorporated | |
|----------------------|--------------------|
| 1240 Deming Way | |
| Madison, WI 53717 | |
| Phone: [phone] | |
| Fax: [phone] | |
| Contact: | Keith Picker |
| Date Prepared: | September 25, 2018 |

## Device Identification

| Device Name: | Motion Tracking and Compensation Feature for the<br>Radixact Treatment Delivery System |
|----------------------|----------------------------------------------------------------------------------------|
| Trade & Brand Names: | Motion Tracking and Compensation Feature for the<br>Radixact Treatment Delivery System |
| Common Name: | Radiation Therapy System |
| Regulation Number: | 21 CFR 892.5050 |
| Regulation Name: | Medical charged-particle radiation therapy system |
| Regulatory Class: | Class II |
| Product Code: | IYE |

## Predicate Device

Radixact Treatment Delivery System (K161146)

## Device Description

The Motion Tracking and Compensation Feature is designed for use with the predicate Radixact Treatment Delivery System last cleared on K161146. The Motion Tracking and Compensation Feature measures tumor location and motion using images provided by a kV imaging subsystem and predicts tumor location based upon a respiration amplitude measurement device. The Radixact Treatment Delivery System then compensates for tumor motion by making real-time adjustments.

The Radixact Treatment Delivery System is a radiation therapy delivery system that provides Image Guided Radiation Therapy (IGRT) using integral megavoltage CT imaging capabilities and delivers helical (rotational) and fixed-angle (non-rotational) radiation therapy to tumors and other targeted tissues.

{4}------------------------------------------------

Neither the Radixact Treatment Delivery System nor the Motion Tracking and Compensation Feature disease, recommend treatment regimens or quantify treatment effectiveness. Accordingly, they are not intended for diagnostic use.

# Intended Use

The Motion Tracking and Compensation Feature is an option within the intended use of the Radixact Treatment Delivery System. The Radixact Treatment Delivery System is intended to be used for the delivery of radiation therapy, stereotactic radiotherapy or stereotactic radiosurgery to tumors or other targeted tissues. The megavoltage x-ray radiation is delivered using rotational, non-rotational, intensity modulated (IMRT), or non-modulated (non-IMRT/three dimensional conformal) treatment techniques and using image-guided (IGRT) or non-image-guided workflows in accordance with the physician approved plan.

# Indications for Use

The Motion Tracking and Compensation Feature is an option within the indications for use of the Radixact Treatment Delivery System. The Radixact Treatment Delivery System is indicated for the delivery of radiation therapy, stereotactic radiotherapy or stereotactic radiosurgery to tumors or other targeted tissues anywhere in the body under the direction of a licensed medical practitioner.

The intended use and indications for use statements for the Motion Tracking and Compensation Feature (shown above) are the same as for the Radixact Treatment Delivery System (last cleared on K161146), except for the addition of the introductory sentence.

# Technological Characteristics

The Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature has imaging and treatment capabilities equivalent to those of the predicate Radixact Treatment Delivery System. It also has a similar functionallyequivalent CT style gantry and patient couch.

The intended use and indications for use of the Motion Tracking and Compensation Feature fit within those of the predicate Radixact Treatment Delivery System. Additionally, the predicate and subject devices have substantially equivalent performance specifications and technological characteristics. Further, the Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature and the predicate device employ the same fundamental scientific principles and have substantially equivalent principles of operation. The main difference between the predicate and the subject device is the use of the motion tracking and compensation feature. Where there are technological differences between the subject and predicate devices, those differences do not raise different questions of safety or effectiveness.

{5}------------------------------------------------

A substantial equivalence table comparing the similarities and differences between the Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature and the predicate device is presented below. The minor differences between the subject and predicate devices do not raise different questions of safety or effectiveness.

| Device<br>Characteristic | Predicate Device<br>Radixact Treatment<br>Delivery System<br>(K161146) | Subject Device<br>Radixact Treatment Delivery<br>System with Motion Tracking<br>and Compensation Feature | Analysis |
|--------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| System Description | | | |
| Intended Use | Omitted for brevity.<br>Reference 510(k)<br>Summary (Section 8<br>of 510(k) submission) | Same as predicate | Identical |
| Indications for Use | Omitted for brevity.<br>Reference 510(k)<br>Summary (Section 8<br>of 510(k) submission) | Same as predicate | Identical |
| System<br>Configuration | Stand-alone radiation<br>delivery system (does<br>not include data<br>management system<br>or planning system) | Stand-alone radiation delivery<br>system with kV imaging and<br>motion tracking and<br>compensation added (does not<br>include data management<br>system or planning system) | Substantially<br>equivalent. The<br>introduction of the<br>Motion Tracking and<br>Compensation Feature<br>does not raise different<br>issues of safety or<br>effectiveness. |
| Vault (Treatment Room) | | | |
| Minimum Room<br>Dimensions<br>(H*W*L) | 274 x 462 x 602 cm | 274.3 x 463 x 602 cm | Substantially<br>equivalent. Minor<br>differences are<br>negligible. |
| Device<br>Dimensions<br>(gantry and couch)<br>(H*W*L) | 255 x 280 x 473 cm | 255 x 280 x 470.5 cm | Substantially<br>equivalent. Minor<br>differences are<br>negligible. |
| Device Mass (kg) | 6580 kg | 6580 kg plus 235 kg for kV<br>subsystem components | The weight added due<br>to the kV subsystem<br>does not result in<br>different questions of<br>safety or effectiveness |
| Device<br>Characteristic | Predicate Device<br>Radixact Treatment<br>Delivery System<br>(K161146) | Subject Device<br>Radixact Treatment Delivery<br>System with Motion Tracking<br>and Compensation Feature | Analysis |
| Line Voltage | 380 - 480 V ac<br>3-Phase | Same as predicate | Identical |
| Ambient Room<br>Temperature | 20 – 24 °C | Same as predicate | Identical |
| Relative Humidity<br>(non-condensing) | 30 – 60 % | Same as predicate | Identical |
| <b>Gantry Mechanical Features</b> | | | |
| Bore Diameter | 85 cm | Same as predicate | Identical |
| Degrees of<br>Rotation | Continuous rotation<br>around Y- axis (axes<br>per IEC 61217) | Same as predicate | Identical |
| Direction of<br>Rotation | Clockwise (as viewed<br>from the foot of the<br>couch) | Same as predicate | Identical |
| Rotational Speed<br>(Treatment) | 1 – 5 RPM | Same as predicate | Identical |
| Rotational Speed<br>(Imaging) | 10 RPM | Same as predicate | Identical |
| Couch Support in<br>Bore | Provided | Same as predicate | Identical |
| <b>Radiation Delivery Modes</b> | | | |
| Description | Helical, Direct | Same as predicate | Identical |
| <b>Photon Beam</b> | | | |
| Accelerator Type | Standing wave | Same as predicate | Identical |
| RF Source | Magnetron | Same as predicate | Identical |
| Nominal Energy | 6 MV | Same as predicate | Identical |
| Fixed Field Size | 1.0 cm x 40 cm<br>2.5 cm x 40 cm<br>5.0 cm x 40 cm | Same as predicate | Identical |
| Dynamic Field<br>Size | 1.0 – 2.5 cm x 40 cm<br>1.0 - 5.0 cm x 40 cm | Same as predicate | Identical |
| Dose Rate | 850 cGy/min<br>standard<br>1000 cGy/min<br>optional | Same as predicate | Identical |
| <b>Collimation</b> | | | |
| Description | Primary collimation,<br>jaws and multi-leaf | Primary collimation, jaws and<br>multi-leaf collimator | Substantially<br>equivalent. Jaws have |
| Device<br>Characteristic | Predicate Device<br>Radixact Treatment<br>Delivery System<br>(K161146) | Subject Device<br>Radixact Treatment Delivery<br>System with Motion Tracking<br>and Compensation Feature | Analysis |
| | collimator | | a new dynamic<br>behavior for motion<br>managed plans. Jaws<br>will continually be<br>adjusted to repoint the<br>beam at the moving<br>target (in IEC-Y)<br>while maintaining the<br>same field size. |
| MVCT Imaging | | | |
| Source | Megavoltage<br>Computed<br>Tomography<br>(MVCT) | Same as predicate | Identical |
| Field of View<br>(MVCT) | 39 cm diameter | Same as predicate | Identical |
| Dose per MVCT<br>Image (typical) | 0.5 - 3.0 cGy | Same as predicate | Identical |
| Slice Spacing<br>(MVCT) | 1, 2, 3, 4 and 6 mm<br>reconstruction<br>intervals | Same as predicate | Identical |
| Spatial Resolution<br>(MVCT) | 1.6 mm | Same as predicate | Identical |
| kV Imaging | | | |
| Source | Feature not present | 50-150 kV Radiography Class I<br>(60601-2-28) X-ray tube<br>assembly | The kV Imaging<br>subsystem provides<br>two-dimensional low- |
| Field of View | Feature not present | 20 cm x 20 cm | dose radiographic |
| Spatial Resolution<br>(kV) | Feature not present | < 1 mm | images used for<br>patient alignment and |
| Approximate Dose<br>per kV x-ray<br>image (range) | Feature not present | 0.08 - 0.20 mGy | measurement of tumor<br>motion during<br>treatment delivery. |
| Small Focal Spot<br>Size | Feature not present | 0.6 mm x 0.6 mm | The functionality is<br>provided by hardware<br>and driver software. A<br>kV radiograph can be<br>performed at any<br>arbitrary angle. A<br>stable calibration from |
| Large Focus Spot<br>Size | Feature not present | 1.0 mm x 1.0 mm | |
| Current Range<br>(mA) | Feature not present | 5 - 500 mA | |
| Device<br>Characteristic | Predicate Device<br>Radixact Treatment<br>Delivery System<br>(K161146) | Subject Device<br>Radixact Treatment Delivery<br>System with Motion Tracking<br>and Compensation Feature | Analysis |
| | | | the kV Imaging<br>coordinate system to<br>the machine<br>coordinate system is<br>made during<br>configuration of the<br>TDS. The new kV<br>imaging components<br>meet applicable safety<br>requirements in the<br>IEC 60601 series. |
| Motion Management | | | |
| Tracking<br>Algorithm | Not present | Radixact Motion Tracking | Substantially<br>equivalent. The<br>introduction of the<br>Motion Tracking and<br>Compensation Feature<br>is based on the core<br>tracking algorithm<br>introduced in<br>K120233, Synchrony<br>Respiratory Tracking<br>System. |
| Compensation<br>Algorithm | Not present | Radixact Motion Compensation | The compensation<br>algorithm uses the<br>jaws and MLC to<br>effectively repoint the<br>beam to accommodate<br>for motion in a method<br>substantially<br>equivalent to<br>K120233, Synchrony<br>Respiratory Tracking<br>System.<br>Does not result in<br>different questions of<br>safety or effectiveness. |
| Synchrony Camera | Not present | Radixact Synchrony Motion<br>Tracking | Substantially<br>equivalent. The<br>Synchrony camera has |
| Device<br>Characteristic | Predicate Device<br>Radixact Treatment<br>Delivery System<br>(K161146) | Subject Device<br>Radixact Treatment Delivery<br>System with Motion Tracking<br>and Compensation Feature | Analysis |
| Laser System | | | been in use for over<br>ten years and was<br>included most recently<br>in K120233,<br>Synchrony<br>Respiratory Tracking<br>System. |
| Stationary | Green lasers identify<br>virtual and actual<br>isocenter | Substantially equivalent | Minor differences are<br>negligible and do not<br>result in different<br>questions of safety or<br>effectiveness. |
| Moveable<br>(for patient<br>positioning and<br>registration) | Red lasers identify<br>offset from virtual<br>isocenter | Substantially equivalent | Minor differences are<br>negligible and do not<br>result in different<br>questions of safety or<br>effectiveness. |
| Patient Couch | | | |
| Motion | Independent of each<br>of the other axes | Independent of each of the other<br>axes | Identical |
| Biocompatibility | | | |
| Couch Top | Carbon-fiber top | Carbon-fiber top | Identical |
| Synchrony Vest | Not Used | Same vest cleared under<br>K120233, Synchrony<br>Respiratory Tracking System | No new<br>biocompatibility<br>issues |
| Power Distribution | | | |
| Isolation | Transformer | Transformer | Substantially<br>equivalent. The<br>introduction of the<br>Motion Tracking and<br>Compensation Feature<br>did not introduce<br>changes to this<br>subsystem. |
| UPS for Data<br>Back-up | Provided | Provided | Substantially<br>equivalent. The<br>introduction of the<br>Motion Tracking and<br>Compensation Feature |
| Device<br>Characteristic | Predicate Device<br>Radixact Treatment<br>Delivery System<br>(K161146) | Subject Device<br>Radixact Treatment Delivery<br>System with Motion Tracking<br>and Compensation Feature | Analysis |
| Operator Station (Treatment Delivery Console) | | | did not introduce<br>changes to this design |
| | Description | User interface to<br>system functions (i.e.,<br>patient and procedure<br>selection, and<br>procedure delivery) | User interface to system<br>functions (i.e., patient and<br>procedure selection, and<br>procedure delivery) |
| | | | |
| Machine Control Software | | | |
| | Description | Controls radiation<br>delivery and<br>positioning systems<br>(referred to as the<br>ECS – Embedded<br>Controls Subsystem) | Controls radiation delivery and<br>positioning systems (referred to<br>as the ECS - Embedded<br>Controls Subsystem) |
| | Data Interfaces<br>Operator Station | Provides<br>measurements and<br>status during<br>operation | Provides measurements and<br>status during operation |
| Database | | | |
| | Description | External database<br>used for gathering<br>operational data and<br>storage of procedure<br>data | External database used for<br>gathering operational data and<br>storage of procedure data |
| | | | |
| Device<br>Characteristic | Predicate Device<br>Radixact Treatment<br>Delivery System<br>(K161146) | Subject Device<br>Radixact Treatment Delivery<br>System with Motion Tracking<br>and Compensation Feature | Analysis |
| Safety Features | | | |
| Interlock<br>Subsystems | Present | Present | Substantially<br>equivalent. kV<br>subsystem integrated<br>into the Safety<br>Interlocks. No<br>different issues of<br>safety or effectiveness. |
| Data integrity<br>checking | Present | Present | Substantially<br>equivalent. The<br>introduction of the<br>Motion Tracking and<br>Compensation Feature<br>does not modify this<br>design. |

# Device Comparison Table: Radixact Treatment Delivery System with Motion Tracking and Compensation Feature

{6}------------------------------------------------

{7}------------------------------------------------

{8}------------------------------------------------

{9}------------------------------------------------

{10}------------------------------------------------

{11}------------------------------------------------

# Performance Data

The Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature was tested and shown to comply with the requirements of applicable FDA recognized consensus safety standards for radiation therapy equipment. Results of verification and validation testing confirm that the use of the Motion Tracking and Compensation Feature on the Radixact Treatment Delivery System conforms to design specifications and meets the needs of the intended users.

No animal or clinical tests were required to establish substantial equivalence with the predicate device. The performance data demonstrate that the Motion Tracking and Compensation Feature is compatible with the Radixact Treatment Delivery System, and the Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature is as safe and effective and performs as well as the predicate device. Further, these test results demonstrate that the Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature has substantially equivalent safety and performance characteristics in comparison to the predicate device.

# Conclusion

The Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature is substantially equivalent to the predicate device. The intended use and indications for use of the Motion Tracking and Compensation Feature fit within those of the predicate Radixact Treatment Delivery System. Additionally, the major technological characteristics and the principles of operation of the Radixact Treatment

{12}------------------------------------------------

Delivery System with the use of the Motion Tracking and Compensation Feature are substantially equivalent to those of the predicate device. Minor differences do not raise different questions of safety and effectiveness of the Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature in comparison to the predicate device. Further, the performance data demonstrate that the Motion Tracking and Compensation Feature is compatible with the Radixact Treatment Delivery System, and the Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature is as safe and effective and performs as well as the predicate device. Therefore, the Radixact Treatment Delivery System with the use of the Motion Tracking and Compensation Feature is substantially equivalent to the predicate device.