(66 days)
The Picker Diffusion-Weighted MR Imaging Package has been designed to image the diffusive mobility of water or other proton-containing molecules. One important clinical application is to visualize the apparent loss of mobility of water molecules in brain tissue affected by acute stroke. Areas of decreased diffusion, as is observed in acute cerebral infarcts, appear as areas of higher image intensity.
Diffusion-weighted MR pulse sequences are more accurate than conventional MRI pulse sequences in identifying the occurrence of acute stroke during the first 24 hours after onset of symptoms.
The Picker Diffusion-Weighted MR Imaging Package does not change the technological characteristics of the Picker MR Systems. This package consists of echo-planar imaging (EPI) single-shot based sequences which have selectable directionality and either fixed or selectable b-values. The sequences are basically spin-echo sequences which have large gradient pulses or lobes before and after the 180° RF refocusing pulse.
The provided document is limited in the information it offers regarding acceptance criteria and detailed study data. This appears to be a 510(k) summary, which often relies on demonstrating substantial equivalence to a predicate device rather than presenting extensive de novo performance studies.
Here's an analysis based on the available text:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state numerical acceptance criteria (e.g., specific sensitivity, specificity, or image quality metrics) or report performance against such criteria for the new device. Instead, it relies on demonstrating substantial equivalence to predicate devices. The "Performance Specifications" for the new device are listed as "Same" as the predicate device (K954646).
| Parameter | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Sequence Description | Substantially equivalent to predicate (K971055) | "Same" as predicate: Echo-Planar Sequence with large magnetic field gradient pulse before and after the 180° refocusing RF pulse. |
| b-value | Fixed and variable sequences available | "Fixed and variable sequences available." |
| Data Correction Calibration | Substantially equivalent to predicate (K954646) | "Same" as predicate: Semi-automatic prescan process. |
| Performance Specifications | Substantially equivalent to predicate (K954646) | "Same" as predicate. (Specific metrics not detailed) |
| Safety Parameters | Substantially equivalent to predicate (K954646) | "Same" as predicate. (Specific parameters not detailed) |
| Intended Use / Indications | Substantially equivalent to predicate (K971055) | "Same" as predicate: Imaging diffusive mobility of water/proton-containing molecules, visualizing apparent loss of mobility in brain tissue affected by acute stroke, identifying acute stroke within 24 hours (more accurate than conventional MRI). |
2. Sample Size Used for the Test Set and Data Provenance
The document does not report any specific test set sample size or data provenance (e.g., country of origin, retrospective/prospective) for a study performed directly on the "Picker Diffusion-Weighted MR Imaging Package." The entire submission is based on demonstrating substantial equivalence to previously approved devices.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
Not Applicable. Since no specific test set study on the new device is described, there's no mention of experts or their qualifications for establishing ground truth. The substantial equivalence argument relies on prior approvals of predicate devices.
4. Adjudication Method for the Test Set
Not Applicable. No test set study for the new device is detailed.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done
No. The document does not describe an MRMC study or any comparative effectiveness study with or without AI assistance. This device predates the widespread use of AI in medical imaging interpretation, and the focus is on a new imaging sequence.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
Yes, implicitly. The device itself is an imaging sequence, not an interpretative algorithm. Its performance is inherent in its ability to generate images that show "areas of decreased diffusion...as areas of higher image intensity" for acute stroke. The claim that "Diffusion-weighted MR pulse sequences are more accurate than conventional MRI pulse sequences in identifying the occurrence of acute stroke during the first 24 hours after onset of symptoms" is a standalone performance claim, but it refers to the class of DWI sequences, not a specific study on this particular Picker package. The documentation does not provide a standalone performance study for this specific package.
7. The Type of Ground Truth Used
For the claim about DWI's accuracy in identifying acute stroke, the ground truth would typically be clinical diagnosis of acute stroke, often confirmed by follow-up imaging, clinical course, or potentially pathology if available, but the document doesn't specify. For the substantial equivalence argument, the "ground truth" is that the predicate devices were deemed safe and effective based on their prior submissions, which would have had their own ground truth methods.
8. The Sample Size for the Training Set
Not Applicable. This device is an MRI sequence, not a machine learning algorithm, so there is no "training set."
9. How the Ground Truth for the Training Set Was Established
Not Applicable. As there is no training set, there is no ground truth for it.
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6 1998 FEB
SUMMARY OF SAFETY AND EFFECTIVENESS
(As required by 21 CFR 807.92)
General Information 1.
| Classification: | Class IIMagnetic Resonance (MR) Diagnostic Device |
|---|---|
| Common/Usual Name: | Magnetic Resonance (MR) Device Option |
| Proprietary Name: | Diffusion-Weighted MR Imaging Package |
| Establishment Registration: | Picker International, Inc.World Headquarters595 Miner RoadHighland Heights, Ohio 44143FDA Owner Number: #1580240FDA Registration Number: #1525965 |
| Performance Standards: | No applicable performance standards have beenissued under section 514 of the Food, Drug andCosmetic Act. |
Intended Uses 2.
The Picker Diffusion-Weighted MR Imaging Package has been designed to image the diffusive mobility of water or other proton-containing molecules. One important clinical application is to visualize the apparent loss of mobility of water molecules in brain tissue affected by acute stroke. Areas of decreased diffusion, as is observed in acute cerebral infarcts, appear as areas of higher image intensity.
Diffusion-weighted MR pulse sequences are more accurate than conventional MRI pulse sequences in identifying the occurrence of acute stroke during the first 24 hours after onset of symptoms.
Device Description 3.
The Picker Diffusion-Weighted MR Imaging Package does not change the technological characteristics of the Picker MR Systems. This package consists of echo-planar imaging (EPI) single-shot based sequences which have selectable directionality and either fixed or selectable b-values. The sequences are basically spin-echo sequences which have large gradient pulses or lobes before and after the 180° RF refocusing pulse.
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Safety and Effectiveness 4.
The Picker Diffusion-Weighted Imaging Package is similar in technological characteristics and intended use to Picker MR systems with Echo-Planar Imaging Capability and the Siemens Diffusion-Weighted Imaging Package. The following table has been created to demonstrate their substantial equivalence.
| Parameter | Diffusion-Weighted MRImaging Package | Predicate DevicesPicker EPI-II Option - K954646Siemens DWI - K971055 |
|---|---|---|
| Sequence Description | Same. | Echo-Planar Sequence with largemagnetic field gradient pulsebefore and after the 180°refocusing RF pulse. (K971055) |
| b-value | Fixed and variable sequencesavailable. | Siemens -- unknown. |
| Data Correction Calibration | Same. | Semi-automatic prescan process(K954646) |
| Performance Specifications | Same. | (K954646) |
| Safety Parameters | Same. | (K954646) |
SUBSTANTIAL EQUIVALENCE TABLE
(
(DWI)
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| Intended Use / Indicationsfor Use | Same. | The Siemens Diffusion-WeightedMR Imaging Package has beendesigned to image the diffusivemobility of water or other proton-containing molecules. Oneimportant clinical application is tovisualize the apparent loss ofmobility by water molecules inbrain tissue affected by acutestroke. Areas of decreaseddiffusion, as is observed in acutecerebral infarcts, appear as areas ofhigher image intensity. |
|---|---|---|
| Diffusion-weighted MR pulsesequences are more accurate thanconventional MRI pulse sequencesin identifying the occurrence ofacute stroke during the first 24hours after onset of symptoms.(K971055) |
.
: 上一篇:
(
:
(DWI) 1 1/25/97 .
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Image /page/3/Picture/0 description: The image shows the logo for the Department of Health & Human Services USA. The logo is a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" around the perimeter. Inside the circle is an abstract image of an eagle.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
6 1998 FEB
Elaine K. Keeler Manager, MR Clinical Science Picker International, Inc. 595 Miner Road Highland Heights. Ohio 44143 Re:
K974530 Diffusion Weighted MRI Package Dated: November 25, 1997 Received: December 2, 1997 Regulatory class: II 21 CFR 8921000/Procode: 90 LNH
Dear Ms. Keeler:
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 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 (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic OS 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 virgo diagnostic devices), please contact the Office of Compliance at (301) 594-4613. Additionally, for question 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/cdrh/dsmamain.html".
Sincerely yours.
h. Tiau Yu.
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 Weighted Imaging Package
Indications for Use:
ﮐﻢ ﻣﯿﮟ ﻣﯿﮟ ﻭﺍﻗﻊ ﮨﮯ۔
The Picker Diffusion-Weighted MR Imaging Package has been designed to image the diffusive mobility of water or other proton-containing molecules. One important clinical application is to visualize the apparent loss of mobility of water molecules in brain tissue affected by acute stroke. Areas of decreased diffusion, as is observed in acute cerebral infarcts, appear as areas of higher image intensity.
Diffusion weighted MR pulse sequences are more accurate than conventional MRI pulse sequences in identifying the occurrence of acute stroke during the first 24 hours after onset of symptoms.
(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
David G. Ferguson
(Division Sign-Off)
Division of Reproductive, Abdominal, ENT, and Radiological Devices 97453 510(k) Number
Prescription Use (Per 21 CFR 801.109)
OR
Over-The-Counter Use (Optional Format 1-2-96)
§ 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.