The AccuLeaf 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. The AccuLeaf enables irregular fields treatments to be performed with finely shaped patterns. In this application the AccuLeaf performs the same function as customized beam shaping blocks, and circular or cut blocks collimators, which have been used for many years

Device Description

AccuLeaf is a LINAC based Micro-Multi-Leaf-Collimator (MMLC), used during both conformal stereotactic radiotherapy and conformal stereotactic radiosurgery. It enables shaping the LINAC beam according to tumor shape and clinical demands. The device is composed of the MMLC module, the LINAC interface module, the Workstation (with AccuLeaf-CS), and the Distribution module. The device is operated in conjunction with a LINAC, its treatment couch, a data file that contains the desired aperture parameters, and any additional equipment required during radiotherapy/ radiosurgery.

AI/ML Overview

Here's an analysis of the provided 510(k) summary regarding the AccuLeaf device, focusing on the requested information:

Summary of Acceptance Criteria and Study Details for AccuLeaf

The provided 510(k) summary for the AccuLeaf device does not explicitly describe specific acceptance criteria in a quantitative or qualitative manner, nor does it detail a study performed to prove the device meets such criteria.

Instead, the submission primarily focuses on establishing substantial equivalence to a predicate device (BrainLAB Med. GmbH's Micro-Multi Leaf Collimator (K970586)). The core argument for safety and effectiveness is that AccuLeaf performs the same function as customized beam shaping blocks and other collimators that have been used for many years, and that validations and performance testing results support this equivalence without raising new safety and/or effectiveness issues.

Here's a breakdown of the requested information based on the provided text, with significant gaps noted:

Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria	Reported Device Performance
Not explicitly stated as quantitative acceptance criteria. The general intent is to perform the same function as existing beam shaping methods (customized blocks, circular/cut blocks).	The device's description and intended use state that it "enables irregular fields treatments to be performed with finely shaped patterns" and "performs the same function as customized beam shaping blocks, and circular or cut blocks collimators, which have been used for many years."
Compliance with voluntary standards:	AccuLeaf complies with:
* IEC 60601-1 (1990) +A1 (1993) +A2 (1995)	Yes
* IEC 60601-1-1 (2000)	Yes
* IEC 60601-1-2 (1993)	Yes
* IEC 60601-1-4 (2000)	Yes
No specific quantitative performance metrics (e.g., accuracy of leaf positioning, leakage, transmission, dose conformity limits) are provided as acceptance criteria.	The submission implies that "validations and performance testing results" demonstrated substantial equivalence, but the specifics of these results are not detailed.

Note: 510(k) summaries often do not include the detailed performance data from bench testing or clinical studies. This document only provides a high-level overview. For the detailed acceptance criteria and performance data, one would typically need to review the full 510(k) submission, including the testing protocols and results submitted to the FDA.

Sample size used for the test set and the data provenance
- Sample Size: Not specified. The document refers to "validations and performance testing results" but does not detail the nature or sample size of these tests. Given it's a hardware device (Multi-Leaf Collimator), the "test set" would likely refer to engineering and bench testing, not a clinical data set in the way an AI algorithm might use one.
- Data Provenance: Not specified. Again, for a hardware device validation, this would refer more to the origin of the test materials, LINACs used, etc., which are not detailed here. It's likely these were internal company tests.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not applicable/Not specified. The ground truth for a device like a multi-leaf collimator would be based on engineering specifications, physical measurements (e.g., leaf position accuracy, radiation field shaping), and established physics principles, rather than expert consensus on medical images or diagnoses.
Adjudication method for the test set
- Not applicable/Not specified. Adjudication methods like 2+1 or 3+1 are typically used for clinical study endpoints, particularly when human readers are involved in interpreting data. This is not described for the AccuLeaf.
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 study is mentioned. This device is a mechanical component of a LINAC used in radiation therapy, not an AI-powered diagnostic or assistive tool for human readers. Therefore, the concept of "human readers improve with AI vs without AI assistance" does not apply to the AccuLeaf as described.
If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- Not applicable. The AccuLeaf is a hardware device (MMLC) that operates in conjunction with a LINAC and its associated software (AccuLeaf-CS) to shape radiation beams. It is not an "algorithm only" device in the sense of a standalone AI solution. Its performance is inherent to its mechanical and control functionality. The document indicates it's "operated in conjunction with a LINAC, its treatment couch, a data file that contains the desired aperture parameters."
The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- The ground truth for evaluating an MMLC would primarily be engineering specifications, physical dosimetry, and mechanical accuracy measurements. This would involve ensuring the leaves move to the commanded positions accurately, maintain their shape, minimize leakage between leaves, and effectively conform the radiation field to the intended shape. This is measured against design performance targets, not against clinical outcomes or pathology directly.
The sample size for the training set
- Not applicable. This device is not an AI/machine learning product that requires a "training set" in the conventional sense. Its "training" would be its design, manufacturing, and calibration processes.
How the ground truth for the training set was established
- Not applicable, as there is no "training set" for an MMLC in the AI/ML context.

In conclusion, the 510(k) summary for AccuLeaf establishes substantial equivalence by demonstrating that the device performs the same function as legally marketed predicate devices and complies with relevant voluntary electrical safety and EMC standards. It does not provide detailed quantitative acceptance criteria or the specific results of performance testing, nor does it involve the types of studies typically conducted for AI-powered diagnostic or assistive devices. The "study" referenced implicitly is the "validations and performance testing" which supports the claim of substantial equivalence but is not detailed in this summary.

Summary

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

510(K) SUMMARY

AccuLeaf 510(k) Number Koz | 33 S

Applicant's Name:

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

Tel: (508) 6510900 Fax: (508) 6518125

Contact Person:

Larisa Gershtein Tel: (508) 6510900 Fax: (508) 6518125

Trade Name: AccuKnife

Model:

AccuLeaf

Classification Name:

Medical Linear Accelerator

Classification:

The FDA has classified this type of devices as class II (product code 90 IYE, Regulation No. 892.5050) and they are reviewed by the Radiology Panel.

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

Predicate Devices:

BrainLAB Med. GmbH's Micro-Multi Leaf Collimator (K970586)

Performance Standards:

No performance standards have been established for such device under Section 514 of the Federal Food, Drug, and Cosmetic Act. However, AccuLeaf complies with the following voluntary standards: IEC 60601-1 (1990) +A1 (1993) +A2 (1995); IEC 60601-1-1 (2000); IEC 60601-1-2 (1993); IEC 60601-1-4 (2000).

Intended Use:

The AccuLeaf enables irregular fields treatments to be performed with finely shaped patterns. In this application the AccuLeaf performs the same function as customized beam shaping blocks, and circular or cut blocks collimators, which have been used for many years

Device Description:

Substantial Equivalence:

Based on validations and performance testing results, Direx Systems Corp. believes that AccuLeaf is substantially equivalent to the predicate device cited above without raising new safety and/or effectiveness issues.

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

Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized caduceus symbol, which is often associated with healthcare. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circular pattern around the caduceus.

Public Health Service

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

JAN 0 7 2003

Ms. Larisa Gershtein OA Manager DiREX Systems Corp. 11 Mercer Road NATICK MA 01760

Re: K021338 Trade/Device Name: AccuLeaf Regulation Number: 21 CFR 892.5050 Regulation Name: Medical charged-particle radiation system Regulatory Class: II Product Code: 90 IYE

Dated: October 7, 2002 Received: October 11, 2002

Dear Ms. Gershtein:

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. 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.

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); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (sections 531-542 of the Act); 21 CFR 1000-1050.

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

This letter will allow you to begin marketing your device as described in your 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:

8xx.1xxx	(301) 594-4591
876.2xxx, 3xxx, 4xxx, 5xxx	(301) 594-4616
884.2xxx, 3xxx, 4xxx, 5xxx, 6xxx	(301) 594-4616
892.2xxx, 3xxx, 4xxx, 5xxx	(301) 594-4654
Other	(301) 594-4692

Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained 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/dsma/dsmamain.html.

Sincerely yours,

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

Enclosure

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

INDICATIONS FOR USE STATEMENT

510(k) Number (if known): K021338

Device Name:

AccuLeaf

Indications for Use:

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

510(k) Number L021338

Prescription Use (Per 21 CFR 801.109)

Over the Use

Counter

David A. Leymon

(Division Sign-Off Division of Reproductive, I and Radiological Devic 7-6 510(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.