AcculCAS is software intended to be used for performing calculations in X-ray angiographic images of the intracranial vessels. AcculCAS enables neurointerventionalists to obtain quantifications of one or more lesions in the analyzed intracranial vessel segment. In particular, AccuICAS provides:
Quantitative results of intracranial vessel segments based on a 3D reconstructed model;
Dimensions of the intracranial vessels and lesions;
Quantification of the pressure gradient (PG) and pressure ratio (PR) in intracranial vessels.
AccuICAS is indicated for use in clinical settings where validated and reproducible quantified results are needed to support the assessment of intracranial vessels in X-ray angiographic images.
When the quantified results provided by AccuICAS are used in a clinical setting on X-ray images of an individual patient, the results are only intended for use by the responsible clinicians.

Device Description

ArteryFlow AcculCAS is designed as a stand-alone software package to run on a PC. This software can read traditional x-ray angiographic images with DICOM format from the local file directory.
AcculCAS is composed of the following analysis workflows: Image Loading, Frame Selection, Vessel Reconstruction and Hemodynamics Calculation for visualization of the target intracranial vessel segment, quantification of morphological parameters and pressure drop of the intracranial vessel segment. AcculCAS is only for quantitative imaging output but not for diagnosis.
AcculCAS calculates the pressure gradient (PG) and pressure ratio (PR) value for the intracranial vessel. To obtain these values for a specific lesion in an intracranial vessel, the user needs to start with Frame Selection using the same vessel under different angulation. In each of these images, a classic 2D intracranial vessel contour detection is performed, after which a reconstruction of the intracranial vessel segment is obtained in 3D space. Based on the 3D reconstruction and patients' mean arterial pressure, the corresponding pressure gradient (PG) and pressure ratio (PR) value at each position can be calculated.
AcculCAS enables neurointerventionalists to obtain accurate anatomical quantifications of one or more lesions in the analyzed intracranial vessel segment, and to assess the best viewing angles which can be helpful for optimal visualization of the lesion.
AcculCAS's outputs mainly include quantitative dimension results of intracranial vessel and lesions segments based on a 3D reconstructed model and quantification of the pressure gradient (PG) and pressure ratio (PR) in intracranial vessels. Besides, other information provided to the end user also belongs to the outputs, such as display of reference vessels and lesions, display of target vessel lumen contour, 3D reconstructed model of intracranial vessels, the diameter stenosis distribution and PG/PR distributions.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study details for the AccuICAS device, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly present a table of acceptance criteria with numerical targets. Instead, it describes a qualitative acceptance: that "All of these tests met the predefined criteria, indicating that the AccuICAS algorithm is accurate, and the device is clinically acceptable." The performance is described by the successful validation of various outputs and calculations.

Acceptance Criterion (Implied)	Reported Device Performance
Software Requirements Met	All requirements are tested, and all results of the tests performed are summarized in the software test report, providing traceability between requirements, design, and successfully executed tests.
Segmentation and Reconstruction Accuracy	Verified through the verification of the lumen and reference lumen contours and the verification of the 3D model. (Implies visual and/or quantitative assessment of accuracy, though specific metrics like Dice/IoU are not provided).
Morphological Parameters Accuracy	Verified using three brass phantoms and a dozen clinical data. (Implies the device's measurements for dimensions, etc., were accurate against known phantom values and clinical observations, though specific metrics like mean absolute error or agreement are not provided).
Diameter Stenosis & PG/PR Distributions Accuracy	Verified using data from several clinical patients with stenosis lesions. (Implies the calculated distributions aligned with clinical findings, though specific metrics for correlation or agreement are not provided).
Hemodynamics Calculation (PG/PR) Accuracy	Validated by comparing the calculated results with measured results. The comparison showed good correlation and agreement between the calculated and measured pressure gradients (PG) and pressure ratios (PR). (Implies high statistical correlation and agreement, though specific correlation coefficients, Bland-Altman agreement limits, or specific "measured results" are not detailed). The document also notes it was compared to "measured results," which implies a gold standard rather than expert consensus on images.
Overall Clinical Acceptability / Accuracy of Algorithm	All validation tests met the predefined criteria.
Safety and Effectiveness Equivalence to Predicate	AccuICAS is "as safe and effective as its predicate device." Differences do not raise new questions of safety and effectiveness.

2. Sample Sizes Used for the Test Set and Data Provenance

Sample Size:
- Morphological parameters: "three brass phantoms and a dozen clinical data." (A dozen typically means 12, so 15 total, 12 clinical data points).
- Diameter stenosis distribution, PG/PR distributions: "several clinical patients with stenosis lesions." (The exact number is not specified but is less precise than "a dozen").
- Hemodynamics calculation: "calculated results with the measured results." (Implies the testing involved a dataset that had both device-calculated and independently measured PG/PR values, but the sample size is not stated beyond "results").
Data Provenance: The document does not explicitly state the country of origin for the clinical data or whether it was retrospective or prospective. Given the submitter's address (Hangzhou, CHINA), it is possible the clinical data originated from China, but this is not confirmed. The nature (retrospective/prospective) is also not specified.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications

The document does not specify the number of experts used or their qualifications for establishing ground truth for the test set. The ground truth for hemodynamics validation seems to have come from "measured results" rather than expert consensus on images.

4. Adjudication Method for the Test Set

The document does not describe any adjudication method (e.g., 2+1, 3+1) for the test set. The validation seems to rely on comparisons against phantoms, "measured results," and unspecified clinical data outcomes.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done, What was the Effect Size of how much human readers improve with AI vs without AI assistance

No MRMC comparative effectiveness study involving human readers with and without AI assistance is mentioned or described in the provided text. The device is for "quantitative imaging output but not for diagnosis" and the validation focuses on the accuracy of its calculations.

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

Yes, the performance data presented appears to be a standalone (algorithm only) evaluation. The validation described tests the accuracy of the algorithm's outputs (segmentation, reconstruction, morphological parameters, hemodynamics calculations) against established references (phantoms, measured results), not against human interpretation assisted by the AI.

7. The Type of Ground Truth Used

Phantoms: For morphological parameters (brass phantoms).
"Measured Results": For hemodynamics calculations (PG and PR values). This suggests an independent, possibly invasive or highly accurate, method of obtaining these measurements, rather than clinical consensus readings from images.
Clinical Data/Patient Observations: For diameter stenosis and PG/PR distributions, and implicitly for the "dozen clinical data" for morphological parameters. The exact nature of how this "ground truth" was established for clinical data is not specified (e.g., expert consensus, other imaging modalities, surgical findings, pathology reports, or long-term outcomes). However, the phrasing "compared the calculated results with the measured results" for PG/PR strongly implies an objective, independent measurement was the ground truth for that specific aspect.

8. The Sample Size for the Training Set

The document does not provide any information about the sample size used for the training set.

9. How the Ground Truth for the Training Set Was Established

The document does not provide any information about how the ground truth for the training set was established.

Summary

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February 28, 2023

Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: a symbol on the left and the FDA acronym with the agency's name on the right. The symbol on the left is a stylized representation of the Department of Health and Human Services seal. The right side of the logo features the FDA acronym in a blue square, followed by the words "U.S. FOOD & DRUG ADMINISTRATION" in blue text.

ArteryFlow Technology Co., Ltd. % Ashley Fu RA Specialist 459 Oianmo Road, Suite C1-501, Binjiang District, Hangzhou, ZHEJIANG 310051 CHINA

Re: K221711

Trade/Device Name: AccuICAS Regulation Number: 21 CFR 892.1600 Regulation Name: Angiographic X-Ray System Regulatory Class: Class II Product Code: QHA, LLZ Dated: January 17, 2023 Received: January 18, 2023

Dear Ashley Fu:

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

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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/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); 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 https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

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/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). 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 (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Lu Jiang

Lu Jiang, Ph.D. Assistant Director Diagnostic X-Ray Systems Team DHT8B: Division of Imaging Devices and Electronic Products OHT8: Office of Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration

Indications for Use

Form Approved: OMB No. 0910-0120 Expiration Date: 06/30/2023 See PRA Statement below.

510(k) Number (if known) K221711

Device Name AccuICAS

Indications for Use (Describe)

AcculCAS is software intended to be used for performing calculations in X-ray angiographic innages of the intracranial vessels. AcculCAS enables neurointerventionalists to obtain quantifications of one or more lesions in the analyzed intracranial vessel segment. In particular, AccuICAS provides:

· Ouantitative results of intracranial vessel segments based on a 3D reconstructed model:

· Dimensions of the intracranial vessels and lesions;

· Quantification of the pressure gradient (PG) and pressure ratio (PR) in intracranial vessels.

AcculCAS is indicated for use in clinical settings where validated and reproducible quantified results are needed to support the assessment of intracranial vessels in X-ray angiographic images.

When the quantified results provided by AcculCAS are used in a clinical setting on X-ray images of an individual patient, the results are only intended for use by the responsible clinicians.

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

X Prescription Use (Part 21 CFR 801 Subpart D)

| Over-The-Counter Use (21 CFR 801 Subpart C)

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 PRAStaff(@fda.hhs.gov

"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."

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Tab #06 510(k) Summary

This summary of 510(k) safety and effectiveness information is being submitted in accordance with requirements of 21 CFR 807.92.

1. Submitter's Information

Submitter: ArteryFlow Technology Co., Ltd.

Address: 459 Qianmo Road, Suite C1-501, Binjiang District, 310051 Hangzhou City, Zhejiang Province, China

Phone Number: +86-571-86772567

Primary correspondent: Jianping Xiang, PhD, General Manager

Email: jianping.xiang@arteryflow.com

Secondary correspondent: Ashley Fu, RA Specialist

Email: fang.fu@arteryflow.com

Date of preparation: February 28, 2023

2. Device Information

Trade/ Device Name: AcculCAS

Common Name: Radiological Image Processing Software

Regulatory Class: Class II

Regulation Description: Angiographic X-ray system

Regulation number: 892.1600

Classification Product Code: QHA

Subsequent Product Code: LLZ

3. Predicate Device Information

Manufacturer: ArteryFlow Technology Co., Ltd.

Device Name: AccuFFRangio

Regulatory Class: Class II

Regulation Number: 892.1600

Classification Product Code: QHA

Subsequent Product Code: LLZ

510(k) number: K210093

4. Device Description

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ArteryFlow AcculCAS is designed as a stand-alone software package to run on a PC. This software can read traditional x-ray angiographic images with DICOM format from the local file directory.

AcculCAS is composed of the following analysis workflows: Image Loading, Frame Selection, Vessel Reconstruction and Hemodynamics Calculation for visualization of the target intracranial vessel segment, quantification of morphological parameters and pressure drop of the intracranial vessel segment. AcculCAS is only for quantitative imaging output but not for diagnosis.

AcculCAS calculates the pressure gradient (PG) and pressure ratio (PR) value for the intracranial vessel. To obtain these values for a specific lesion in an intracranial vessel, the user needs to start with Frame Selection using the same vessel under different angulation. In each of these images, a classic 2D intracranial vessel contour detection is performed, after which a reconstruction of the intracranial vessel segment is obtained in 3D space. Based on the 3D reconstruction and patients' mean arterial pressure, the corresponding pressure gradient (PG) and pressure ratio (PR) value at each position can be calculated.

AcculCAS enables neurointerventionalists to obtain accurate anatomical quantifications of one or more lesions in the analyzed intracranial vessel segment, and to assess the best viewing angles which can be helpful for optimal visualization of the lesion.

AcculCAS's outputs mainly include quantitative dimension results of intracranial vessel and lesions segments based on a 3D reconstructed model and quantification of the pressure gradient (PG) and pressure ratio (PR) in intracranial vessels. Besides, other information provided to the end user also belongs to the outputs, such as display of reference vessels and lesions, display of target vessel lumen contour, 3D reconstructed model of intracranial vessels, the diameter stenosis distribution and PG/PR distributions.

5. Indications for Use

Quantitative results of intracranial vessel seqments based on a 3D reconstructed model:
Dimensions of the intracranial vessels and lesions;
Quantification of the pressure gradient (PG) and pressure ratio (PR) in intracranial vessels.

AcculCAS is indicated for use in clinical settings where validated and reproducible quantified results are needed to support the assessment of intracranial vessels in X-ray angiographic images.

When the quantified results provided by AcculCAS are used in a clinical setting on X-ray images of an individual patient, the results are only intended for use by the responsible

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clinicians.

6. Technological Characteristic Comparison

A comparison of the technological characteristics of the predicate and subject device is given in the table below.

Item	New device	Predicate device
Device name	AccuICAS	AccuFFRangio
Manufacturer	ArteryFlow Technology Co., Ltd.	ArteryFlow Technology Co., Ltd.
510(k) No.	-	K210093
Product Code	QHA, LLZ	QHA, LLZ
Regulation No.	892.1600	892.1600
Class	II	II
Level of Concernof the software	Moderate	Moderate
Intended use /Indications for use	Indications for UseAccuICAS is software intended tobe used for performingcalculations in X-ray angiographicimages of the intracranialvessels. AccuICAS enablesneurointerventionalists to obtainquantifications of one or morelesions in the analyzedintracranial vessel segment. Inparticular, AccuICAS provides:Quantitative results ofintracranial vessel segmentsbased on a 3D reconstructedmodel;Dimensions of theintracranial vessels andlesions;Quantification of thepressure gradient (PG) andpressure ratio (PR) inintracranial vessels.AccuICAS is indicated for use inclinical settings where validatedand reproducible quantifiedresults are needed to support theassessment of intracranialvessels in X-ray angiographic	AccuFFRangio is softwareintended to be used forperforming calculations in X-rayangiographic images of thecoronary arteries.AccuFFRangio enablesinterventional cardiologists toobtain quantifications of one ormore lesions in the analyzedcoronary vessel segment. Inparticular, AccuFFRangioprovides:Quantitative results ofcoronary vessel segmentsbased on a 3D reconstructedmodel;Dimensions of thecardiovascular vessels andlesions;Quantification of thepressure drop in coronaryvessels.AccuFFRangio is indicated foruse in clinical settings wherevalidated and reproduciblequantified results are needed tosupport the assessment of

	images.When the quantified resultsprovided by AccuICAS are usedin a clinical setting on X-rayimages of an individual patient,the results are only intended foruse by the responsible clinicians.	coronary vessels in X-rayangiographic images, for use onindividual patients with coronaryartery disease.When the quantified resultsprovided by AccuFFRangio areused in a clinical setting on X-rayimages of an individual patient,the results are only intended foruse by the responsible clinicians.
	Technological Characteristics
Data type	● X-ray angiographic data inDICOM format (vendor-independent)	● X-ray angiographic data inDICOM format (vendor-independent)
Import of patientdata	● Automatically loadinformation from patient'sDICOM file;● Manual through keyboard	● Automatically loadinformation from patient'sDICOM file;● Manual through keyboard
Image display	● 2D X-ray image visualization● 3D reconstruction of thevessel segment based on 2X-ray images;● Graph for actual andreference vessel diameterwith vessel longitudinalposition;● Graph for hemodynamicsparameter value (PG/PR)with vessel longitudinalposition;● Hemodynamics parametervalue (PG/PR) is colored onthe 3D reconstructed vesselsegment model.	● 2D X-ray image visualization● 3D reconstruction of thevessel segment based on 2X-ray images;● Graph for actual andreference vessel diameterwith vessel longitudinalposition;● Graph for AccuFFRangio(FFR) value with vessellongitudinal position;● AccuFFRangio (FFR) valueis colored on the 3Dreconstructed vesselsegment model.
Centerlineandcontour definition	● Manual and semi-automaticcenterline definition basedon contour detection ofvessel;● Contour correction andrestriction	● Manual and semi-automaticcenterline definition basedon contour detection ofvessel;● Contour correction andrestriction
Imageassessment	● Manual and automaticcalibration;● Vessel dimensions	● Manual and automaticcalibration;● Vessel dimensions
	assessment;• Pressure drop calculation inintracranial vessel	assessment;• Pressure drop calculation incoronary vessel
Storage of results	• Printout• Images• PDF	• Printout• Images• PDF
Softwareoperationenvironment	• Linux Ubuntu 18.04, 64-bitversion• Microsoft Windows 10, 64-bitversion• MacOS 11.4, 64-bit version	• Linux Ubuntu16.04 and18.04, 32 and 64-bit version• Microsoft Windows 7, SP1,32 and 64-bit version• Microsoft Windows 8.1, 32and 64-bit version• Microsoft Windows 10, 32and 64-bit version

Table 1 General Comparison

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AcculCAS is a quantitative imaging output device as the predicate devices. AcculCAS share the same intended use of performing calculations in X-ray angiographic images with the predicate device AccuFFRangio (K210093). Both products could enable medical professionals to obtain quantifications of one or more lesions based on a 3D reconstructed model and dimensions of vessels. The main outputs of both are morphological parameters and hemodynamics parameters.

Besides, AcculCAS has same software algorithms and technical characteristics with predicate device AccuFFRangio (K210093).

The minor gaps exist in lesion location of indications for use, intended patient population and software operating environment. However, the differences are not critical to the intended use of the device, and do not affect the safety and effectiveness of the device when used as labeled.

7. Performance Data

Software requirements – derived from the intended use and indications for use – as well as risk control measures are verified by system testing. All requirements are tested and all results of the tests performed are summarized in the software test report and especially the requirements coverage matrix of AcculCAS providing traceability between requirements, design and the tests successfully executed.

All outputs of the device have undergone validation to ensure that they support the intended use of the device:

The segmentation and reconstruction outputs were verified through the verification of the lumen and reference lumen contours and the verification of 3D model.
Morphological parameters output by AcculCAS was verified using three brass phantoms and a dozen clinical data.
The diameter stenosis distribution, as well as the PG and PR distributions, were verified using data from several clinical patients with stenosis lesions.

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Hemodynamics calculation was validated by comparing the calculated results with the measured results. The comparison showed good correlation and agreement between the calculated and measured pressure gradients (PG) and pressure ratios (PR).
All of these tests met the predefined criteria, indicating that the AcculCAS algorithm is accurate, and the device is clinically acceptable.

8. Conclusion

Based on the information provided in this submission, AcculCAS shares same intended use, software algorithms and technical characteristics with the predicate device AccuFFRangio (K210093).

Verification and validation testing have produced results consistent with design input requirements. During the development, potential hazards were controlled by a risk management report, including risk analysis, risk mitigation and validation.

ArteryFlow Technology concludes that AcculCAS, intended only for quantitative imaging output but not for diagnosis, is as safe and effective as its predicate device. The difference between the subject and predicate devices do not raise new questions of safety and effectiveness.

Regulation Number and Section

§ 892.1600 Angiographic x-ray system.

(a)
Identification. An angiographic x-ray system is a device intended for radiologic visualization of the heart, blood vessels, or lymphatic system during or after injection of a contrast medium. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.