AccuChanger is intended to assist the radiation oncologist in the delivery of radiation to well defined target volumes while sparing surrounding normal tissue and critical organs from excess radiation. It is intended to be used for the collimation of megavoltage photon beams in conjunction with Stereotactic Radio Surgery (SRS) and Stereotactic Radio Therapy (SRT) treatments.

Device Description

AccuChanger device is designed to be used for the Linac beam shaping during radiotherapy. It constitutes an add-on to a Linac used for automatic switching of circular collimators during treatments without entering the treatment room. AccuChanger uses a two-level circular-collimator set. It has two drums one mounted on top of the other. Each drum has nine drumb one mounted in a descending order of radius. Although it is possible for the collimation to combine any pair of collimators lo possible as a drum, only seventeen combinations are deemed valid. Each valid combination is forming a circular aperture valia. Back value of the circular collimators (upper/lower) is set as the beam shaping collimator, the other (lower/upper respectively) is set as a post/pre bounding "protecting" collimator to reduce radiation transmission. To start a treatment, a treatment file is needed specifying the aperture diameter at the isocenter for each of the treatment beams (defined input format). AccuChanger-CS calculates the fitting collimator size on one drum and chooses the best match on the other. Since the matching pairs are known in advance, a lookup table is used obviating the need of re-calculating the appropriate collimators pair.

AI/ML Overview

The provided text is a 510(k) summary for the "AccuChanger" device. This document focuses on establishing substantial equivalence to predicate devices for regulatory clearance, rather than presenting a detailed study proving the device meets specific performance acceptance criteria in the way a clinical study would for an AI/ML diagnostic tool.

Therefore, many of the requested details about acceptance criteria, full performance studies, sample sizes, ground truth establishment, and MRMC effectiveness studies are not available in this type of regulatory submission. The document primarily describes the intended use, device function, and comparison to predicate devices to demonstrate that it does not raise new safety or effectiveness concerns.

Here's a breakdown of the available information based on your request, along with explanations for what is not present:

Acceptance Criteria and Device Performance (Not in the context of a typical AI/ML study)

This 510(k) summary does not include a table of acceptance criteria and reported device performance in the manner of a clinical sensitivity/specificity study for an AI/ML product. The document asserts that the AccuChanger performs the same function as existing devices (shaping blocks, circular/cut blocks collimators) and complies with voluntary IEC safety standards.

Table of "Acceptance Criteria" and "Reported Device Performance":

Acceptance Criteria (Implied by Regulatory Submission)	Reported Device Performance (Implied by Description)
Safety and Effectiveness Equivalence: Does not raise new questions of safety or effectiveness compared to predicate devices.	"Any minor differences between the systems do not raise new types of safety or effectiveness issues."
Intended Use Equivalence: Performs the same function as predicate devices for beam shaping.	"AccuChanger performs the same function [as] shaping blocks, and circular or cut blocks collimators, which have been used for many years."
Compliance with Voluntary Standards: Adheres to relevant safety standards.	Complies with IEC 60601-1 (2000), IEC 60601-1-1 (2000), IEC 60601-1-2 (2001), IEC 60601-1-4, Ed. 1.1 (2000).
Functionality: Capable of automatic switching of circular collimators during treatments without entering the treatment room.	Uses a "two-level circular-collimator set" with two drums and pre-determined valid combinations for circular apertures; uses a lookup table for matching collimator pairs.

Additional Information

Sample sizes used for the test set and the data provenance:
- Not Applicable. This document is for a mechanical medical device (a linear accelerator accessory), not an AI/ML algorithm that relies on a "test set" of data for performance evaluation in the traditional sense. There is no mention of a test set, data provenance, or specific patient data used to evaluate its "performance."
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not Applicable. Ground truth, in the context of expert consensus on data, is not mentioned or relevant for this type of device. The device's function is mechanical manipulation of collimators, not diagnostic interpretation.
Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not Applicable. No test set or human adjudication method is described.
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. This is not an AI-assisted diagnostic device. No MRMC study was performed or is relevant.
If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- Not Applicable. This device is an accessory to a linear accelerator, operated by a radiation oncologist or technician, and does not involve a standalone algorithm for performance evaluation in isolation from its mechanical function.
The type of ground truth used (expert concensus, pathology, outcomes data, etc):
- Not Applicable. The "ground truth" for this device would be its ability to physically position the correct collimators and ensure accurate beam shaping, which is verified through engineering tests and quality control, not clinical "ground truth" derived from patient data. The document does not describe such studies.
The sample size for the training set:
- Not Applicable. This is not an AI/ML device that requires a training set of data.
How the ground truth for the training set was established:
- Not Applicable. No training set for an AI/ML algorithm is used in this context.

Summary of what the document does provide:

Intended Use: To assist radiation oncologists in delivering radiation to target volumes while sparing critical organs, specifically for Linac beam shaping during radiotherapy, including Stereotactic Radiosurgery (SRS) and Stereotactic Radiotherapy (SRT). It performs the function of shaping blocks/collimators.
Device Description: An add-on to a Linac for automatic switching of circular collimators, using a two-level circular-collimator set with two drums. It contains a lookup table for pre-determined collimator pairs based on a specified aperture diameter.
Predicate Devices: AccuLeaf K040553, Cranial Stereotactic Equipment K010065, XKnife K912630.
Substantial Equivalence Claim: The device has "identical intended use and indications for use" as AccuLeaf, operates on "similar principles of operation and technological characteristics" to all predicates, and "does not present any new method of treatment." Minor differences do not raise new safety or effectiveness issues.
Compliance: Adheres to voluntary IEC 60601-1 series standards.

This 510(k) is a regulatory filing for a mechanical accessory, and therefore, the detailed study information you're asking for, typical of AI/ML or diagnostic device submissions, is not present.

Summary

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510(K) SUMMARY

AccuChanger

MAY - 5 2005

510(k) Number K 043409

Applicant's Name:

Direx Systems Corp. 11 Mercer Road, Natick Business Park Natick, MA 01760 United States of America

Contact Person:

Larisa Gershtein Direx Systems Corp. 11 Mercer Road, Natick Business park Natick, MA 01760 United States of America Tel: (508) 6510900 Fax: (508) 6518125

Trade Name:

AccuChanger

Model:

AccuChanger

Classification Name:

Accelerator, Linear, Medical

Classification:

The FDA has classified this type of devices as class II (product code IXI, Regulation No. 892.5710). They are reviewed by the Radiology Panel.

Establishment Registration Number

1224828

Predicate Devices:

The predicate devices for substantial equivalence are:

1. AccuLeaf K040553, DIREX Systems Corp.
1. Cranial Stereotactic Equipment, K010065 Arplay/ BrainLab
1. XKnife K912630, Radionics Software Applications, Inc.,

Performance Standards:

No performance standards have been established for such device under Section 514 of the Federal Food, Drug, and Cosmetic Act.

However, AccuChanger complies with these voluntary standards:

IEC 60601-1 (2000); IEC 60601-1-1 (2000); IEC 60601-1-2 (2001);

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IEC 60601-1-4, Ed. 1.1 (2000).

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Intended Use:

AccuChanger is intended to assist the radiation oncologist in the Accuentanys is in the well defined target volumes while sparing delively of radiation to won and critical organs from excess radiation.

In this application the AccuChanger performs the same function i in this application shaping blocks, and circular or cut blocks collimators, which have been used for many years.

Device Description:

AccuChanger uses a two-level circular-collimator set. It has two drums one mounted on top of the other. Each drum has nine drumb one mounted in a descending order of radius. Although it is possible for the collimation to combine any pair of collimators lo possible as a drum, only seventeen combinations are deemed valid. Each valid combination is forming a circular aperture valia. Back value of the circular collimators (upper/lower) is set as the beam shaping collimator, the other (lower/upper respectively) is set as a post/pre bounding "protecting" collimator to reduce radiation transmission.

To start a treatment, a treatment file is needed specifying the aperture diameter at the isocenter for each of the treatment beams (defined input format). AccuChanger-CS calculates the fitting collimator size on one drum and chooses the best match on the other. Since the matching pairs are known in advance, a lookup table is used obviating the need of re-calculating the appropriate collimators pair.

Substantial Equivalence:

We claim AccuChanger to be SE to:

AccuLeaf K040553, DIREX Systems Corp. 1.
It has identical intended use and indications for use as AccuLeaf.
Cranial Stereotactic Equipment, K010065 Arplay/BrainLab 2.
XKnife K912630, Radionics Software Applications, Inc., 3.

All compared devices have similar principles of operation and technological characteristics. Furthermore, AccuChanger does not present any new method of treatment other than its predicate devices. Any minor differences between the systems do not raise new types of safety or effectiveness issues, as further discussed below.

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MAY - 5 2005

Image /page/3/Picture/1 description: The image is a black and white logo for the U.S. Department of Health and Human Services. The logo features a stylized eagle with three stripes forming its body and wings. The eagle is encircled by the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" in a circular arrangement.

Public Health Service

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Ms. Larisa Gershtein QA Manager DiREX Systems Corp. 11 Mercer Road

NATICK MA 01760

Re: K043409 Trade/Device Name: AccuChanger Regulation Number: 21 CFR 892.5050 Regulation Name: Medical charged-particle radiation therapy system Regulatory Class: II Product Code: IYE Dated: April 14, 2005 Received: April 18, 2005

Dear Ms. Gershtein:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced we have and have determined the device is substantially equivalent (for the indications for use stated in above una nave determinerarketed predicate devices marketed in interstate commerce prior to the cholore) to regardy mant date of the Medical Device Amendments, or to devices that have been May 20, 1770, the charanteness 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 do not require approval or a ve visions of the Act. The general controls provisions of the Act device, subjoct to the general registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (Premarket If your de rever is elabelied (500 acch additional controls. Existing major regulations affecting your Apploval), it the you sable 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 I toase oe advisou that your device complies with other requirements of the Act or any I DA has made a acteriminations administered by other Federal agencies. You must comply with all the I cacan states and regulating, but not limited to registration and listing (21 CFR Part 807); labeling Act 3 requirements, moraling practice requirements as set forth in the quality systems (QS) (21 CFR Part 80 7), good mo if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of Compliance at one of the following numbers, based on the regulation number at the top of this letter:

21 CFR 876.xxxx	(Gastroenterology/Renal/Urology)	240-276-0115
21 CFR 884.xxxx	(Obstetrics/Gynecology)	240-276-0115
21 CFR 892.xxxx	(Radiology)	240-276-0120
Other		240-276-0100

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.

Sincerely yours,

Nancy C. Brogdon

Nancy C. Brogdon Director, Division of Reproductive, Abdominal, and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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AccuChanger

510(k) Number (if known): K043409

PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use V And (Per 21 CFR 801.109)

Over-The-Counter Use

(Optional Format 1-2-96)

Nancy C. Brogdon

(Division Sian-Off) Division of Reproductive, Abdominal, and Radiological Devices 510(k) Number

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.