The modification is a cardiac gating technique referred to as Retrospective Gating. In standard cardiac gating, the acquisition is triggered by the QRS pulse of the ECG. In Retrospective Gating, the scan runs continuously, and the correlation with the QRS cycle is done after the fact. This modification does not involve any changes to the existing hardware of the predicate devices.

AI/ML Overview

The provided 510(k) summary for Elscint's "Retrospective Gating for Elscint MRI Systems" describes a modification to existing MRI systems. However, its focus is on demonstrating substantial equivalence to predicate devices rather than proving the device meets specific performance acceptance criteria through a detailed study.

Here's an analysis of the submission based on your request, highlighting what is and isn't available:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria	Reported Device Performance
Safety Parameters Unchanged: SAR, dB/dt, Bo, acoustic noise, electrical, mechanical, biocompatibility, and software hazards.	"The MRI safety parameters, SAR, dB/dt, Bo, and acoustic noise, are unchanged by the current modification.""Electrical, mechanical, and biocompatibility safety issues are unchanged by the current modification.""No new software hazards have been introduced, so the software level of concern remains minor."
Effectiveness - Image Comparability: Retrospective Gating option produces images comparable with those produced using standard cardiac gating.	"The MRI performance parameters remain unchanged. The Retrospective Gating option produces images that are comparable with those produced using the standard cardiac gating technique."

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

Not explicitly stated. The submission mentions image comparability to existing techniques but does not quantify the sample size (number of patients/scans) used to assess this comparability.
Data Provenance: Not explicitly stated. Given it's a 510(k) for a device modification, it's likely the "comparable images" refer to internal testing performed by Elscint. It does not specify country of origin or whether it was retrospective or prospective data.

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

Not applicable / Not explicitly stated. The submission focuses on demonstrating safety and "comparable" image quality to an existing method, implying visual assessment by company engineers/experts. There is no mention of independent experts establishing ground truth for a test set.

4. Adjudication Method for the Test Set

Not applicable / Not explicitly stated. No formal adjudication method is described, as the study design for evaluating "comparability" is not detailed.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done, Effect Size

No. A formal MRMC comparative effectiveness study, as understood in current regulatory submissions for AI/CAD devices, was not performed or described. This submission predates the widespread use of such studies for AI evaluation in medical imaging. The submission simply states images are "comparable" to standard gating.

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

Yes, implicitly. This is a modification to an MRI system's acquisition technique, not an AI/CAD algorithm that provides diagnoses or measurements. The "performance" being evaluated is the direct output of the modified MRI system (the images themselves). The statement "The Retrospective Gating option produces images that are comparable with those produced using the standard cardiac gating technique" implies a standalone assessment of the image quality produced by the system.

7. The Type of Ground Truth Used

Implied Expert Observation/Standard of Care: The "ground truth" here is the established quality and diagnostic utility of images produced by the standard cardiac gating technique. The new technique simply needed to demonstrate that its output images were similar in quality and diagnostic information. This would have been assessed by developers and possibly clinical collaborators comparing the two sets of images. It's not "pathology" or "outcomes data" in the typical sense for a diagnostic algorithm, but rather a performative comparison to an existing, validated imaging method.

8. The Sample Size for the Training Set

Not applicable / Not explicitly stated. This device modification is to an MRI acquisition technique, not an AI / machine learning algorithm that requires a "training set" in the modern sense. The term "training set" is not relevant to this submission.

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

Not applicable. As this is not an AI/ML device, there is no "training set" or corresponding ground truth establishment process in this context.

Summary of the Study:

The "study" described in the 510(k) summary is a comparative assessment aimed at demonstrating substantial equivalence to predicate devices. It's not a formal, quantitative performance study with specific metrics, statistical power, and independent adjudication typically seen for novel diagnostic devices. Instead, it relies on proving that the new "Retrospective Gating" technique maintains the same safety profile and produces comparable image quality to established cardiac gating methods within Elscint's existing MRI systems (Gyrex 2T Prestige, Gyrex Privilege, Gyrex Prima 1 TG System). The critical assertion is that "the effectiveness of the modified devices is similar to that of the predicate devices." No detailed study protocol, data, or statistical analysis is provided in this summary. It's a high-level claim of equivalence.

Summary

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510(k) Summary

K974614

1. Submitter's Name and Address: Elscint, Inc., 505 Main Street, Hackensack, NJ 07601
  Contact Person and Telephone No.: Steven M. Kay, (201) 342-2020 MAR - 4 1998

10 December 1997 Date of Summary:

Retrospective Gating for Elscint MRI Systems 2. Device Name: Retrospective Gating for Elscint MRI System Trade/Proprietary Name: MRI System Modification Common Name: Magnetic Resonance Diagnostic Device Classification Name:
Gyrex 2T Prestige system (K945791), Gyrex Privilege 3. Predicate Device(s): System (K954039), Gyrex Prima 1 TG System (K970990)

4. Device Description:

5. Intended Use:

Anatomical Region:	Heart
Nuclei Excited:	Hydrogen
Diagnostic Use:	Production of a series of images of the heart at differentphases of the cardiac cycle.

6. Safety:

The MRI safety parameters, SAR, dB/dt, Bo, and acoustic noise, are unchanged by the . current modification.
Electrical, mechanical, and biocompatibility safety issues are unchanged by the current . modification.
No new software hazards have been introduced, so the software level of concern remains . minor.
The current modification does not affect the site planning, installation, or service . manuals, and do not require any new safety labeling.

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7. Effectiveness:

The MRI performance parameters remain unchanged. The Retrospective Gating option produces images that are comparable with those produced using the standard cardiac gating technique.

8. Equivalency Information Summary:

The FDA recommended MRI safety limits are not exceeded, and the effectiveness of the modified devices is similar to that of the predicate devices. It is Elscint's opinion that the Prestige, Privilege and Prima systems with the new Retrospective Gating option are substantially equivalent to their predicate devices in terms of safety and effectiveness.

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Image /page/2/Picture/0 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized human figure with outstretched arms, enclosed within a circle. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged around the upper portion of the circle.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Beny Sherer Safety Officer Elscint, Inc. 86 Orchard Street Hackensack, NJ 07601 Re:

K974614

MAR - 4 1998

Gyrex 2T Prestige, Privilege and Prima ITG with Retrospective Gating Dated: December 10, 1997 Received: December 11, 1997 Regulatory class: II 21 CFR 892.1000/Procode: 90 LNH

Dear Mr. Sherer:

We have reviewed your Section 510/k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to 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). 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 (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Fecteral Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (OS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition. FDA may publish further announcements concerning your device in the Federal Register. this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

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 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4613. Additionally, for question 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 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address "http://www.fda.gov/odrh/dsmaldsmamain.html".

Sincerely yours,

Kilian Yih

Lillian Yin, Ph.D. Director, Division of Reproductive Abdominal. Far. Nose and Throa and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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510(k) Number (if known):_K 974614

Device Name: Retrospective Gating for Elscint MRI Systems

Indications For Use:

The production of a series of images of the heart at different phases of the cardiac cycle.

(Please do not write below this line - continue on another page if needed)

(Concurrence of CDRH, Office of Device Evaluation (ODE))

Schmid C. Seyfarth
(Division Sign-Off)

Division of Reproductive, Abdominal, ENT, and Radiological Devic 510(k) Number

Prescription Use (Per 21 CFR 801.109)

(

Over-The-Counter Use__________________________________________________________________________________________________________________________________________________________

Regulation Number and Section

§ 892.1000 Magnetic resonance diagnostic device.

(a)
Identification. A magnetic resonance diagnostic device is intended for general diagnostic use to present images which reflect the spatial distribution and/or magnetic resonance spectra which reflect frequency and distribution of nuclei exhibiting nuclear magnetic resonance. Other physical parameters derived from the images and/or spectra may also be produced. The device includes hydrogen-1 (proton) imaging, sodium-23 imaging, hydrogen-1 spectroscopy, phosphorus-31 spectroscopy, and chemical shift imaging (preserving simultaneous frequency and spatial information).(b)
Classification. Class II (special controls). A magnetic resonance imaging disposable kit intended for use with a magnetic resonance diagnostic device only is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.