Diffusion Weighted Imaging is intended for use in generating unique contrast/information about the diffuse mobility of water or other proton containing molecules. Changes in mobility of the apparent diffusion coefficients in tissue can be seen much earlier phase than originally possible with conventional proton density, T1 or T2 weighted imaging. This change indicates neurological anomalies, of which diagnosis of acute stroke is one of the important applications.

Diffusion Weighted Imaging generates contrast/information about the apparent diffusion coefficients that reflect the anisotropic nature of tissue composition (e.g. fiber tracts in brain white matter) that otherwise cannot be visualized by conventional proton density, T1 or T2 weighted imaging.

Device Description

Sensitivity to diffusion has been induced by applying two identical large magnetic field gradient pulses, socalled diffusion gradients, to the basic (SE or SE-EPI) pulse sequences.

One diffusion gradient is applied before the 180 degree refocussing RF pulse and the second after the 180 degree RF pulse. During imaging static spins will be dephased as a result of the first applied diffusion gradient followed by complete rephasing by the second gradient pulse. If the molecules are moving inbetween the two diffusion gradients, non-complete rephasing will occur, resulting in the diffusion weighting. Diffusion Weighted Imaging (DWI) on the Philips Gyroscan NT systems is offered in the following two optional packages:

Diffusion package: allowing basic DWI sequences, based on Spin Echo (SE) sequences in combination . with motion reduction techniques.
Extended Diffusion Package: allowing faster acquisition as DWI is based on Spin Echo Planar ● Imaging (SE-EPI) sequences with motion rechniques. Both Single Shot Diffusion EPI as well as multi-shot Diffusion EPI versions are possible.

AI/ML Overview

The provided 510(k) summary does not contain information about acceptance criteria or a study that proves the device meets those criteria. The document describes the device, its intended use, technological characteristics, and claims substantial equivalence to predicate devices, but it does not present performance data or clinical study results.

Therefore, I cannot provide a table of acceptance criteria and reported device performance or other details about a study.

Here's a breakdown of why the requested information is absent from the provided text:

Acceptance Criteria and Reported Device Performance: This type of information would typically be presented as quantitative metrics (e.g., sensitivity, specificity, accuracy, signal-to-noise ratio, spatial resolution) with target values and the device's demonstrated achievement of those values. The document only discusses general improvements in detecting neurological anomalies earlier.
Sample Size and Data Provenance (Test Set): No test set with specific numbers of cases or their origin (country, retrospective/prospective) is mentioned.
Number of Experts and Qualifications (Ground Truth): There is no mention of experts establishing ground truth or their qualifications.
Adjudication Method: No adjudication method is described.
Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study: The document does not describe any study comparing human readers with and without AI assistance.
Standalone Performance Study: While the device itself is a standalone imaging package, the document does not present a standalone performance study with specific metrics. It talks about the capabilities of the diffusion-weighted imaging but not its performance in a structured study.
Type of Ground Truth Used: The document doesn't specify how the "truth" of neurological anomalies or diffusion coefficient changes would be established for any performance evaluation.
Sample Size for Training Set: No training set is mentioned as this device is a new imaging sequence for an existing MRI system, not an AI/CAD device that requires a training set.
How Ground Truth for Training Set was Established: Not applicable as no training set is mentioned.

The document primarily focuses on demonstrating substantial equivalence to predicate devices by highlighting that the new sequences are extensions of existing, approved MRI techniques and do not introduce new safety risks. This is a common approach for 510(k) submissions where the technology is an evolution rather than a completely novel device with entirely new performance metrics to establish.

Summary

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Philips Medical Systems Nederland B. V.

Image /page/0/Picture/2 description: The image shows the word "PHILIPS" in a bold, sans-serif font. Below the word "PHILIPS" is a series of numbers, "5973658", written in a cursive style. The text is black against a white background. The image appears to be a logo or label.

XJR-148-2985/bf 1997-09-09

510(k) Summary of Safety and Effectiveness.

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

Company Name:		Philips Medical Systems North America Company.
Address:		710 Bridgeport AvenueShelton, CT 06484.
Registration No.:		1217116
Contact person:		Peter Altman
Telephone Number:		203-926-7031
Prepared:	:	September 9th, 1997.
Device Name:		(Extended) DIFFUSION Package / GYROSCAN NT.
Classification Name:		Magnetic Resonance Diagnostic Device.
Classification:		Class II.
Performance standards:		NEMA voluntary standards, FDA MRI guidances, UL and IEC 601 relevantsafety standards and/or draft standards are used.
Common/Usual Name:		Diffusion Weighted MR Imaging.
Predicate Device(s):		- Spin Echo (SE) and Spin Echo Echo Planar (SE-EPI) imaging PhilipsGYROSCAN NT systems ( FDA re. K963990).- SIEMENS Diffusion Weighted MRI / MAGNETOM Vision(FDA re.K971055).

Intended Use :

The (Extended) DIFFUSION Package provides the facility of Diffusion Weighted Imaging (DWI) which generates unique contrastinformation about the diffusive mobility of water or other proton containing molecules. Change of the diffuse mobility of water or other proton containing molecules of tissue can be seen in a much earlier phase than originally possible with conventional proton density, T1 or T2 weighted imaging. This change indicates neurological anomalies of acute stroke is one of the important application.

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Philips Medical Systems

Philips Medical Systems Nederland B. V.

XJR-148-2985/bf 1997-09-09

System Description :

Sensitivity to diffusion has been induced by applying two identical large magnetic field gradient pulses, socalled diffusion gradients, to the basic (SE or SE-EPI) pulse sequences.

Diffusion package: allowing basic DWI sequences, based on Spin Echo (SE) sequences in combination . with motion reduction techniques.
Extended Diffusion Package: allowing faster acquisition as DWI is based on Spin Echo Planar ● Imaging (SE-EPI) sequences with motion rechniques. Both Single Shot Diffusion EPI as well as multi-shot Diffusion EPI versions are possible.

Technological Characteristics:

The technological characteristics remain the same as those for other Gyroscan NT systems. New sequences are available as the option is enabled.

General Safety and Effectiveness Concerns

The new Diffusion Weighted MRI sequences are extensions to the already available Spin Echo (SE), Inversion Recovery (IR) and Spin Echo Echo Planar Imaging (SE-EPI) sequences. Diffusion Weighted Imaging does not induce any other safety risks than the forementioned regular imaging techniques. No other warnings than those already valid for the above mentioned techniques are added to the Operator Manual of Gyroscan NT systems.

Substantial Equivalence

The (Extended) DIFFUSION package is substantially equivalent to the commercially available Grroscan NT sequences like SE, IR and SE-EPI and the Siemens Diffusion Weighted - MR Imaging.

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Image /page/2/Picture/0 description: The image shows the seal of the Department of Health & Human Services USA. The seal features a stylized eagle-like symbol with three curved lines representing wings or feathers. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" is arranged in a circular pattern around the symbol.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

MAY 6 1998

Peter Altman Director of Regulatory Affairs Philips Medical Systems North America Company 710 Bridgeport Avenue P.O. Box 860 Shelton, CT 06484-0917

Re:

K973658

MRI Sequence (Diffusion Imaging Package for Philips Gyroscan NT MR Systems Dated: February 2, 1998 Received: February 5, 1998 Regulatory class: II 21 CFR 892.1000/Procode: 90 LNH

Dear Mr. Altman:

We have reviewed your Section 510%) 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 (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21. Parts 800 to 895. A substantially equivalent determination assumes with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (OS) for Medical Devices: General regulation (2) 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. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 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 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 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/cdrb/dsmaldsmamain.html".

Sincerely yours,

Kilian Yin

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

Enclosure

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510(k) Number (if known):

Device Name :

DIFFUSION and Extended DIFFUSION Package for PhilipsGyroscan NT

出版社会的一次 173658

Indications For Use :

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

David h. Bergman
(Division Sign-Off)

Reproductive, Abdominal. F

510(k) Number K97365

Prescription Use ** ( Per 21 CFR 801.109

Over-The-Counter Use

(Optional Format 1-2-96)

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.