(177 days)
Diffusion Weighted EPI imaging produces magnetic resonance (MR) images whose contrast is dependent on the local diffusion coefficient of water. Diffusion Weighted EPI can be useful in visualizing the apparent loss of diffusion (mobility) by water molecules in brain tissues affected by acute stroke. Diffusion Weighted EPI is more accurate than conventional MRI pulse sequence (ie Fast FLAIR and Fast Spin Echo) in identifying the occurrence of acute stroke.
The Diffusion Weighted EPI Imaging Option provides an additional imaging option to the Echo Planar Imaging pulse sequence. The DW-EPI option is a single shot EPI pulse designed to create images that differentiates tissues with restricted diffusion from tissues with normal diffusion.
Here's a summary of the acceptance criteria and study information for the GE Medical Systems Diffusion Weighted EPI Imaging Option based on the provided text:
Important Note: The provided document is a 510(k) summary for a medical device submitted in 1997. At that time, the regulatory requirements for showing performance and clinical benefit were significantly different (and generally less stringent) than today's standards for AI/ML devices. Therefore, much of the information typically expected for a modern AI device's acceptance criteria and study data (e.g., detailed performance metrics like sensitivity/specificity, specific ground truth methods for clinical endpoints, robust training/test set details, MRMC studies) is not present in this document. The focus of this submission is primarily on demonstrating substantial equivalence to a predicate device and basic safety.
Acceptance Criteria and Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Safety: Device meets international medical equipment safety standards for Magnetic Resonance Systems. | Evaluation testing confirmed compliance with IEC 601-2-33 International medical equipment safety standard for Magnetic Resonance Systems. The opinion of GE is that the Diffusion Weighted EPI Imaging Option does not result in any new potential hazards. |
| Accuracy: Differentiation of tissues with restricted diffusion from tissues with normal diffusion. | The device is designed to create images that differentiate tissues with restricted diffusion from tissues with normal diffusion. |
| Clinical Utility: Useful in visualizing apparent loss of diffusion (mobility) of water molecules in brain tissues affected by acute stroke. | The device produces MR images whose contrast is dependent on the local diffusion coefficient of water. It "can be useful" in visualizing the apparent loss of diffusion (mobility) by water molecules in brain tissues affected by acute stroke. The document states, "Diffusion Weighted EPI is more accurate than conventional MRI pulse sequence (ie Fast FLAIR and Fast Spin Echo) in identifying the occurrence of acute stroke." (However, the study details to support this comparative accuracy claim explicitly are missing/not detailed in the summary.) |
| Substantial Equivalence: To predicate device. | The Diffusion Weighted EPI Imaging Option is substantially equivalent to the currently marketed Siemens Medical System Diffusion Weighted MR Imaging Option (510k #K971055). This implies the predicate already met accepted safety and performance levels deemed adequate by the FDA. |
Study Details
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Sample sizes used for the test set and the data provenance:
- Test Set Sample Size: Not explicitly stated. The "Summary of Studies" section only mentions "Evaluation testing confirmed accuracy statements in the User Manual." It does not provide details on patient cohorts, case numbers, or specific performance metrics from a test set.
- Data Provenance: Not specified.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not specified. The document does not detail how "accuracy statements" were confirmed, nor does it refer to specific clinical ground truth established by experts for performance evaluation beyond general statements about its utility in identifying acute stroke. The primary "ground truth" for regulatory approval appears to be equivalence to the predicate device.
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Adjudication method for the test set:
- Not specified.
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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 comparative effectiveness study is reported. The device is an "imaging option" (a pulse sequence), not an AI-based interpretation tool designed to assist human readers, in the modern sense. The claim is that the imaging sequence itself is "more accurate than conventional MRI pulse sequence" in identifying acute stroke, not that it improves human reader performance through AI assistance.
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If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- This is not an "algorithm-only" or AI device in the contemporary sense. It's an MR imaging pulse sequence. Its "performance" is inherent in the image contrast and information it provides. The study primarily focuses on safety and functional performance of the imaging sequence itself, not on an algorithm's diagnostic output.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Not explicitly stated for clinical accuracy. The document mentions "accuracy statements in the User Manual" were confirmed, but the basis for these statements (e.g., against pathology, clinical follow-up, or expert consensus) is not detailed. For the regulatory submission, the primary "ground truth" was the predicate device and its established safety and performance.
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The sample size for the training set:
- Not applicable as this is an MR imaging pulse sequence, not an AI/ML algorithm that requires a training set in the current understanding. Its development likely involved engineering, physics, and empirical testing for image quality and contrast, rather than data-driven machine learning.
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How the ground truth for the training set was established:
- Not applicable for the same reason as #7.
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Image /page/0/Picture/1 description: The image shows a black and white logo. The logo is circular and contains the letters 'GE' in a stylized font. The letters are intertwined and appear to be handwritten. The logo is simple and recognizable.
GE Medical Systems
PO Box 414. W-709 Milwaukee, WI 53201 USA
SUMMARY OF SAFETY AND EFFECTIVENESS
FEB - 5 1998
- o This 510(k) summary of safety and effectiveness information is submitted in accordance with the requirements of 21 CFR Part 807.87(h).
- o Identification of Submitter Larry A. Kroger, Ph.D., 414-544-3894, August 13, 1997
- o Identification of the Product Diffusion Weighted EPI Imaging Option
Manufactured by:
GE Medical Systems 3200 N. Grandview Blvd. Waukesha. Wi 53188
- o Device Description
The Diffusion Weighted EPI Imaging Option provides an additional imaging option to the Echo Planar Imaging pulse sequence. The DW-EPI option is a single shot EPI pulse designed to create images that differentiates tissues with restricted diffusion from tissues with normal diffusion.
o Indications for Use
Diffusion Weighted EPI imaging produces magnetic resonance (MR) images whose contrast is dependent on the local diffusion coefficient of water. Diffusion Weighted EPI can be useful in visualizing the apparent loss of diffusion (mobility) by water molecules in brain tissues affected by acute stroke.
Diffusion Weighted EPI is more accurate than conventional MRI pulse sequence (ie Fast FLAIR and Fast Spin Echo) in identifying the occurrence of acute stroke.
-
0 Comparison with Predicate
The Diffusion Weighted EPI Imaging Option is substantially equivalent to the currently marketed Siemens Medical System Diffusion Weighted MR Imaging Option (510k #K971055). -
o Summary of Studies
The Diffusion Weighted EPI Imaging Option was evaluated to the IEC 601-2-33 International medical equipment safety standard for Magnetic Resonance Systems. Evaluation testing confirmed accuracy statements in the User Manual. -
o Conclusions
It is the opinion of GE that the Diffusion Weighted EPI Imaging Option does not result in any new potential hazards.
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Image /page/1/Picture/0 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized eagle with its wings spread, symbolizing protection and care. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" is arranged in a circular fashion around the eagle. The logo is simple and monochromatic.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
Larry Kroger, Ph.D. Senior Regulatory Programs Manager GE Medical System PO Box 414, W-709 Milwaukee, WI 53201
Re:
K972990 Diffusion Weighted EPI Imaging Option Dated: November 20, 1997 Received: November 21, 1997 Regulatory class: II 21 CFR 892.1000/Procode: 90 LNH
FEB - 5 1998
Dear Dr. Kroger:
We have reviewed your Section 510(k) notification of intent to market the device 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 Devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, subject to the general controls provisions of the general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either 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 Federal Regulations, Title 21. Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirement, 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. Please note: 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 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 (30) 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/cdrh/dsmamain.html":. -------------------------------------------------------------------------------------------
Sincerely vours,
h. liau Yi
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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Device Name: Diffusion Weighted EPI Imaging Option
Indications For Use:
- ﺬ-
Diffusion Weighted EPI imaging produces magnetic resonance (MR) images whose contrast is dependent on the local diffusion coefficient of water. Diffusion Weighted EPI can be useful in visualizing the apparent loss of diffusion (mobility) by water molecules in brain tissues affected by acute stroke.
Diffusion Weighted EPI is more accurate than conventional MRI pulse sequence (ie Fast FLAIR and Fast Spin Echo) in identifying the occurrence of acute stroke.
(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Wint le Seymon
on of Reproductive, Abdominal, E d Radiological De
510(k) Number K972990
OR
Prescription Use
(Per 21 CFR 801.109) ✓
Over-The-Counter Use__________________________________________________________________________________________________________________________________________________________
§ 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.