StrokeSENS LVO is a radiological computer-aided triage and notification (CADt) software indicated for use in the analysis of CTA head images. The device is intended to assist hospital networks and trained clinicians in workflow triage by flagging and communication of suspected positive findings of Large Vessel Occlusion (LVO) in head CTA images.

StrokeSENS LVO uses a software algorithm to identify suspected LVO findings. In the case of a suspected LVO, the system will send a notification to a pre-configured destination(s), notifying the clinicians of the existence of a suspected LVO that requires review. The notification system is intended to be used in parallel to the standard of care workflow to notify clinicians of the existence of a potential LVO earlier than being notified as part of the standard of care workflow.

Notifications may include a compressed preview of images. Notifications are meant for informational purposes only and are not intended for diagnostic use beyond notification. The StrokeSENS LVO device does not alter the original medical image and is not intended to be used as a diagnostic device.

The results of StrokeSENS LVO are intended to be used in conjunction with other patient information and based on professional judgement, to assist with triage / prioritization of medical images. Notified clinicians are responsible for viewing full images per standard of care.

Device Description

StrokeSENS LVO is intended to assist hospital networks and trained clinicians in workflow triage by flagging and communication of suspected positive findings of Large Vessel Occlusion (LVQ) in head CTA images. StrokeSENS LVO uses a software alqorithm based on machine learning to identify suspected LVO findings. In the case of a suspected LVO, the system will send a notification to a preconfigured destination(s), notifying the clinicians of a suspected LVQ that requires review.

StrokeSENS LVO DICOM-compliant software system consists of two main components: 1) the StrokeSENS LVO Processing Engine and 2) a compatible Radiological Software Platform:

1. The StrokeSENS LVO Processing Engine is responsible for receiving, processing, and analyzing image data and communicating results. Primarily, the Processing Engine consists of a software algorithm (a sequence of instructions/operations) that is responsible for analyzing contrast-enhanced CT (CTA) image data of the head to identify characteristics that are consistent with LVO. The software algorithm is a binary classifier, providing a binary output of either positive or negative for suspected LVO, based on a pre-defined threshold. The output is returned to the Radiological Software Platform for the purposes of triage and notification. The Processing Engine is integrated into, or installed adjacent to, a compatible Radiological Software Platform.
1. The compatible Radiological Software Platform is configured to retrieve/receive contrast-enhanced head CT (CTA) images from the CT scanner or PACS, and automatically transmit, or make available, a copy of the image data for processing and analysis by the LVO Processing Engine. After successful processing of a case via the StrokeSENS LVO Processing Engine, the results are returned to the Radiological Software Platform for the intended purpose of triage and notification.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study details for the StrokeSENS LVO device:

1. Table of Acceptance Criteria and Reported Device Performance

Test	Acceptance Criteria	Reported Device Performance
Sensitivity	Sensitivity > 80%	89.4% (95% CI = 85.3%, 93.5%)
Specificity	Specificity > 80%	87.4% (95% CI = 82.6%, 92.2%)
Processing Time	< 5 minutes	Mean: 0.75 mins, S.D: ±0.17 mins, Min: 0.46 mins, Max: 1.23 mins

2. Sample Size for the Test Set and Data Provenance

Sample Size: 400 independent studies (217 LVO cases and 183 non-LVO cases).
Data Provenance: Retrospective case study. The document does not specify the country of origin, but mentions the dataset had "sufficient representation of relevant parameters such as age, sex, scanner vendor, and slice thickness."

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

The document does not explicitly state the number of experts used or their detailed qualifications (e.g., "radiologist with 10 years of experience"). However, it implies that ground truth for Large Vessel Occlusion (LVO) and non-LVO cases was established by "trained clinicians" as part of the standard of care workflow.

4. Adjudication Method for the Test Set

The document does not specify an adjudication method like 2+1 or 3+1. It implies that the ground truth was established by clinical assessment, likely involving expert review, but the specific process isn't detailed.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not reported. The study focused on the standalone performance of the StrokeSENS LVO device.

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

Yes, a standalone performance study was conducted. The document states: "To demonstrate the standalone performance of StrokeSENS LVO... a retrospective case study was conducted to assess the sensitivity and specificity of StrokeSENS LVO for detecting Large Vessel Occlusion (LVO)."

7. The Type of Ground Truth Used

The ground truth used was based on clinical diagnosis of Large Vessel Occlusion (LVO). This is implied by the classification of cases as "LVO cases" and "non-LVO cases" and the mention of "suspected acute ischemic stroke" in the context of the clinical population. While not explicitly stated as "expert consensus" in a formal sense of the study methodology, the nature of LVO diagnosis usually involves expert radiologists/neurologists.

8. The Sample Size for the Training Set

The document does not specify the sample size used for the training set. It only describes the test set.

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

The document does not describe how the ground truth for the training set was established. It primarily focuses on the validation study using the independent test set.

Summary

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Circle Neurovascular Imaging, Inc % Kyle Mayr Official Correspondent Circle Cardiovascular Imaging, Inc. 800 5th Ave SW Suite 1100 Calgary, Alberta T2P 3T6 Canada

October 21, 2021

Re: K212261

Trade/Device Name: StrokeSENS LVO Regulation Number: 21 CFR 892.2080 Regulation Name: Radiological computer aided triage and notification software Regulatory Class: Class II Product Code: QAS

Dear Kyle Mayr:

The Food and Drug Administration (FDA) is sending this letter to notify you of an administrative change related to your previous substantial equivalence (SE) determination letter dated October 14, 2021. Specifically, FDA is updating this SE Letter to indicate the correct official correspondent contact name and address as an administrative correction.

Please note that the 510(k) submission was not re-reviewed. For questions regarding this letter please contact Jessica Lamb, OHT7: Office of In Vitro Diagnostics and Radiological Health, 301-796-6167, iessica.lamb(@fda.hhs.gov.

Sincerely.

Jessica Lamb

For

Jessica Lamb Assistant Director Mammography Ultrasound and Imaging Software Branch Division of Radiological Health OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health

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Circle Neurovascular Imaging, Inc. % John Smith Hogan Lovells US LLP Columbia Square 555 Thirteenth Street, NW WASHINGTON DC 20004

October 14, 2021

Re: K212261

Trade/Device Name: StrokeSENS LVO Regulation Number: 21 CFR 892.2080 Regulation Name: Radiological computer aided triage and notification software Regulatory Class: Class II Product Code: OAS Dated: July 16, 2021 Received: July 20, 2021

Dear John Smith:

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

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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 mediation-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.

Jessica Lamb

For

Thalia T. Mills, Ph.D. Director Division of Radiological Health OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K212261

Device Name StrokeSENS LVO

Indications for Use (Describe)

StrokeSENS LVO is a radiological computer-aided triage and notification (CADt) software indicated for use in the analysis of CTA head images. The device is intended to assist hospital networks and trained clinicians in workflow trage by flagging and communication of suspected positive findings of Large Vessel Occlusion (LVO) in head CTA images.

StrokeSENS LVO uses a software algorithm to identify suspected LVO findings. In the case of a suspected LVO, the system will send a notification to a pre-configured destination(s), notifying the clinicians of the existence of a suspected L VO that requires review. The notification system is intended to the standard of care workflow to notify clinicians of the existence of the case earlier that they may have been notified as part of the standard of care workflow.

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)
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5.1 510k Summary - StrokeSENS LVO

K212261

I. SUBMITTER

Submitter's Name:
Address:
Date Prepared:
Telephone Number:
Fax Number:
Contact Person:
Email:

Circle Neurovascular Imaging, Inc. Suite 1100 - 800 5th Ave SW, Calgary, AB, Canada, T2P 3T6 July 16, 2021 +1 403 338 1870 +1 403 338 1895 Kyle Mayr kyle.mayr@circlecvi.com

II. DEVICE

Name of the Device: Short Brand Name: Common or Usual Name: Classification Name: Proposed Classification:

StrokeSENS LVO StrokeSENS LVO Medical Image Processing Software Radiological Computer-Assisted Triage And Notification Software Device Class II Special Controls Product Code: QAS Regulation Number: 21 CFR 892.2080

III. PREDICATE DEVICE

ContaCT, manufactured by Viz.Al (DEN170073)

IV. DEVICE DESCRIPTION

Clinical Characteristics and Procedures of Use

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After a CT Angiography (CTA) head scan is performed, the images are automatically routed to StrokeSENS LVO where they are processed and analyzed for characteristics suggestive of LVO. The notification system is comprised of an on-screen notice of a suspected LVQ to the user and an outbound notification to a neurovascular specialist. The notification states that a suspected LVO is present, and that the user should review the images in a diagnostic radiological viewer. In the case of a neqative finding, no notification is sent, and the standard of care workflow remains in place.

Technological Characteristics

StrokeSENS LVO DICOM-compliant software system consists of two main components: 1) the StrokeSENS LVO Processing Engine and 2) a compatible Radiological Software Platform:

1. The StrokeSENS LVO Processing Engine is responsible for receiving, processing, and analyzing image data and communicating results. Primarily, the Processing Engine consists of a software algorithm (a sequence of instructions/operations) that is responsible for analyzing contrast-enhanced CT (CTA) image data of the head to identify characteristics that are consistent with LVO. The software algorithm is a binary classifier, providing a binary output of either positive or negative for suspected LVO, based on a pre-defined threshold. The output is returned to the Radiological Software Platform for the purposes of triage and notification. The Processing Engine is integrated into, or installed adjacent to, a compatible Radiological Software Platform.
1. The compatible Radiological Software Platform is configured to retrieve/receive contrast-enhanced head CT (CTA) images from the CT scanner or PACS, and automatically transmit, or make available, a copy of the image data for processing and analysis by the LVO Processing Engine. After successful processing of a case via the StrokeSENS LVO Processing Engine, the results are returned to the Radiological Software Platform for the intended purpose of triage and notification.

V. INDICATIONS FOR USE/ INTENDED USE

1. Indications for use

StrokeSENS LVO uses a software algorithm to identify suspected LVO findings. In the case of a suspected LVQ, the system will send a notification to a pre-configured destination(s), notifying the clinicians of the existence of a suspected LVO that requires review. The notification system is

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Image /page/6/Picture/0 description: The image is a logo for Circle Neurovascular Imaging. The logo features a cluster of green circles on the left side, resembling a brain. To the right of the circles, the word "CIRCLE" is written in large, bold, black letters. Below "CIRCLE", the words "NEUROVASCULAR IMAGING" are written in smaller, black letters.

intended to be used in parallel to the standard of care workflow to notify clinicians of the existence of a potential LVO earlier than being notified as part of the standard of care workflow.

2. Special Conditions for Use Statement(s):

For prescription use only. US Federal law restricts this device to sale by or on the order of a licensed healthcare practitioner.

VI. COMPARISON WITH PREDICATE DEVICE

StrokeSENS LVO is considered to be substantially equivalent to Viz.Al: ContaCT (hereafter "ContaCT"), a commercially available device manufactured by Viz.Al, Inc. The subject and predicate devices are both radiological computer-assisted triage and notification software programs. Both devices use machine learning software implementations to analyze CTA images to aid in the prioritization, triage, and notification of suspected large vessel occlusion (LVQ) cases. Both software devices notify a designated list of clinicians of the availability of time sensitive radiological medical images for review based on computer aided image analysis performed by the device's algorithm, in parallel to the standard of care workflow. The subject and predicate devices are similar in that neither device alters the original image database or marks up / alters the CTA input images. The subject and predicate device differ in that the subject device generates an email notification that links to the StrokeSENS platform radiological viewing software or other compatible radiological viewing software whereas the predicate generates a notification that is sent to a mobile application.

StrokeSENS LVO has the same general intended use and similar indications, technological characteristics, and principles of operation as the previously cleared predicate device, with minor differences in the notification mechanism. The minor differences do not raise new questions on the safety and effectiveness of the device; therefore the subject device is as safe and effective as the predicate device. A summary substantial equivalence chart comparing the similarities and differences between the StrokeSENS LVO and its predicate device is provided below, as table 5.1-1.

Feature /Characteristic	Subject Device	Predicate Device
General information
Device name	StrokeSENS LVO	ContaCT
Manufacturer	Circle Neurovascular Imaging	Viz.Al
510(k) number	K212261	DEN170073
Device Class	II	II
Device classification	QAS	QAS
Regulation Name	Radiological Computer-AssistedTriage And Notification Software	Radiological Computer-Assisted TriageAnd Notification Software
Regulation number	21 CFR 892.2080	21 CFR 892.2080
Indications for Use /Intended Use	StrokeSENS LVO is aradiological computer-aidedtriage and notification (CADt)software indicated for use in theanalysis of CTA head images.The device is intended to assisthospital networks and trainedclinicians in workflow triage byflagging and communication ofsuspected positive findings ofLarge Vessel Occlusion (LVO) inhead CTA images.StrokeSENS LVO uses asoftware algorithm to identifysuspected LVO findings. In thecase of a suspected LVO, thesystem will send a notification toa pre-configured destination(s),notifying the clinicians of theexistence of a suspected LVOthat requires review. Thenotification system is intended tobe used in parallel to the standardof care workflow to notifyclinicians of the existence of thecase earlier that they may havebeen notified as part of thestandard of care workflow.Notifications may include acompressed preview of images.Notifications are meant forinformational purposes only andare not intended for diagnosticuse beyond notification. TheStrokeSENS LVO device doesnot alter the original medical	ContaCT is a notification-only, parallelworkflow tool for use by hospital networksand trained clinicians to identify andcommunicate images of specific patientsto a specialist, independent of standard ofcare workflow.ContaCT uses an artificial intelligencealgorithm to analyze images for findingssuggestive of a pre-specified clinicalcondition and to notify an appropriatemedical specialist of these findings inparallel to standard of care imageinterpretation. Identification of suspectedfindings is not for diagnostic use beyondnotification. Specifically, the deviceanalyzes CT angiogram images of thebrain acquired in the acute setting, andsends notifications to a neurovascularspecialist that a suspected large vesselocclusion has been identified andrecommends review of those images.Images can be previewed through amobile application. Images that arepreviewed through the mobile applicationare compressed and are for informationalpurposes only and not intended fordiagnostic use beyond notification.Notified clinicians are responsible forviewing non-compressed images on adiagnostic viewer and engaging inappropriate patient evaluation andrelevant discussion with a treatingphysician before making care-relateddecisions or requests. ContaCT is limitedto analysis of imaging data and should notbe used in-lieu of full patient evaluation orrelied upon to make or confirm diagnosis.
	image and is not intended to beused as a diagnostic device.The results of StrokeSENS LVOare intended to be used inconjunction with other patientinformation and based onprofessional judgement, to assistwith triage / prioritization ofmedical images. Notifiedclinicians are responsible forviewing full images per standardof care.
Clinical Characteristics
User Population	Hospital Networks and trainedclinicians	Same
Clinicalapplication/AnatomicalRegion	Acute Stroke / Head	Same
Relationship tostandard of careworkflow	In Parallel / Concurrently	Same
Technological Characteristics
Input data type	CTA data in DICOM format(vendor independent)	CTA data in DICOM format (vendorindependent)
AlgorithmImplementation	Artificial Intelligence / MachineLearningAlgorithms are static and locked.Algorithms are not dynamic orlearning while in the market.	Same
Alteration of originalimage database	No	Same
Notification / Workflow	Email, Workstation, MobileNotification message ofSuspected LVO	MobileNotification message of Suspected LVO
DICOM compliant	Yes	Same

Table 5.1-1. Feature comparison table of StrokeSENS LVO with the predicate device, ContaCT.

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Image /page/9/Picture/0 description: The image is a logo for Circle Neurovascular Imaging. The logo features a cluster of green circles on the left side, resembling a brain. To the right of the circles is the word "CIRCLE" in large, bold, black letters. Below the word "CIRCLE" is the phrase "NEUROVASCULAR IMAGING" in smaller, black letters.

VII. PERFORMANCE DATA

Performance validation testing and software verification activities were conducted to comply with specified design requirements in accordance with applicable consensus standards and to satisfy the special controls of the device classification.

Performance testing was conducted to verify compliance with specified design requirements in accordance with ISO 13485:2016, IEC 62304:2015, IEC 62366:2015 and ISO 14971:2019. DICOM conformance testing was performed to verify compliance with NEMA 3.1-3.20 (2011) standards. Verification and validation testing were conducted to ensure specifications and performance of the device and were performed per the FDA Guidance documents "Guidance for the Content of Premarket Submissions for Software Contained in Medical Devices" and "Content of Premarket Submission for Management of Cybersecurity in Medical Devices". Software performance, verification and validation testing demonstrated that the StrokeSENS system met all design requirements and specifications.

To demonstrate the standalone performance of StrokeSENS LVO in accordance with the 892.2080 special controls, a retrospective case study was conducted to assess the sensitivity and specificity of StrokeSENS LVO for detecting Large Vessel Occlusion (LVO). Performance was reported on a heterogenous dataset of 400 independent studies (217 LVO cases and 183 non-LVO cases). The dataset had sufficient representation of relevant parameters such as age, sex, scanner vendor, and slice thickness. The dataset had a reasonably balanced prevalence of LVO (54.3%; 217 positive cases & 183 negative cases) and includes challenging cases (small/other occlusions and intracranial hemorrhage) that are representative of the clinical population undergoing baseline imaging for suspected acute ischemic stroke.

The StrokeSENS LVO module met the performance targets intended for the clinical performance assessment, as described in table 10.1-3. The device achieved a mean sensitivity of 89.4% Cl = [85.3%, 93.5%], and mean specificity of 87.4% C1 = [82.6%, 92.2%] for the binary LVO detection task on the test set (N=400, LVO=217. Non-LVO=183). In addition, an analysis of time to notify of suspicious cases was conducted by evaluating the average time for the StrokeSENS LVO device to process the CTA image and generate a notification (for LVO positive cases). The device achieved a mean value of 0.75 minutes (S.D: ±0.17 mins, Min: 0.46 mins), which exceeded the qoal of <5 minutes.

Table 5.1-2 LVO validation and performance test summary

Test	Acceptance Criteria	Test Results
Sensitivity	Sensitivity > 80 %	89.4%, (95% CI = 85.3, 93.5)

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Specificity	Specificity > 80 %	87.4%, (95% CI = 82.6, 92.2)
Processing Time	<5 minutes	Mean: 0.75 minsS.D: ±0.17 minsMin: 0.46 minsMax: 1.23 mins

VIII. CONCLUSIONS

The information submitted in this 510k submission, including the performance testing and predicate device comparisons, support the safety and effectiveness of the StrokeSENS LVO software as compared to the predicate device: ContaCT (DEN170073).

The StrokeSENS LVO device has the same intended use and similar indications, technological characteristics, and principles of operation as its predicate device. The minor differences do not alter the intended use of the device and do not affect its safety and effectiveness when used as labeled. Performance data demonstrate that the software functions as intended. Thus, the StrokeSENS LVO device is substantially equivalent.

Regulation Number and Section

§ 892.2080 Radiological computer aided triage and notification software.

(a)
Identification. Radiological computer aided triage and notification software is an image processing prescription device intended to aid in prioritization and triage of radiological medical images. The device notifies a designated list of clinicians of the availability of time sensitive radiological medical images for review based on computer aided image analysis of those images performed by the device. The device does not mark, highlight, or direct users' attention to a specific location in the original image. The device does not remove cases from a reading queue. The device operates in parallel with the standard of care, which remains the default option for all cases.(b)
Classification. Class II (special controls). The special controls for this device are:(1) Design verification and validation must include:
(i) A detailed description of the notification and triage algorithms and all underlying image analysis algorithms including, but not limited to, a detailed description of the algorithm inputs and outputs, each major component or block, how the algorithm affects or relates to clinical practice or patient care, and any algorithm limitations.
(ii) A detailed description of pre-specified performance testing protocols and dataset(s) used to assess whether the device will provide effective triage (
e.g., improved time to review of prioritized images for pre-specified clinicians).(iii) Results from performance testing that demonstrate that the device will provide effective triage. The performance assessment must be based on an appropriate measure to estimate the clinical effectiveness. The test dataset must contain sufficient numbers of cases from important cohorts (
e.g., subsets defined by clinically relevant confounders, effect modifiers, associated diseases, and subsets defined by image acquisition characteristics) such that the performance estimates and confidence intervals for these individual subsets can be characterized with the device for the intended use population and imaging equipment.(iv) Stand-alone performance testing protocols and results of the device.
(v) Appropriate software documentation (
e.g., device hazard analysis; software requirements specification document; software design specification document; traceability analysis; description of verification and validation activities including system level test protocol, pass/fail criteria, and results).(2) Labeling must include the following:
(i) A detailed description of the patient population for which the device is indicated for use;
(ii) A detailed description of the intended user and user training that addresses appropriate use protocols for the device;
(iii) Discussion of warnings, precautions, and limitations must include situations in which the device may fail or may not operate at its expected performance level (
e.g., poor image quality for certain subpopulations), as applicable;(iv) A detailed description of compatible imaging hardware, imaging protocols, and requirements for input images;
(v) Device operating instructions; and
(vi) A detailed summary of the performance testing, including: test methods, dataset characteristics, triage effectiveness (
e.g., improved time to review of prioritized images for pre-specified clinicians), diagnostic accuracy of algorithms informing triage decision, and results with associated statistical uncertainty (e.g., confidence intervals), including a summary of subanalyses on case distributions stratified by relevant confounders, such as lesion and organ characteristics, disease stages, and imaging equipment.

Re: K212261

Indications for Use

Indications for Use (Describe)

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

5.1 510k Summary - StrokeSENS LVO

I. SUBMITTER

III. PREDICATE DEVICE

IV. DEVICE DESCRIPTION

Clinical Characteristics and Procedures of Use

Technological Characteristics

V. INDICATIONS FOR USE/ INTENDED USE

1. Indications for use

2. Special Conditions for Use Statement(s):

VI. COMPARISON WITH PREDICATE DEVICE

VII. PERFORMANCE DATA

VIII. CONCLUSIONS

§ 892.2080 Radiological computer aided triage and notification software.

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