K981094 · Medrad, Inc. · MOS · Jun 18, 1998 · Radiology
Device Facts
Record ID
K981094
Device Name
MEDRAD NEUROVASCULAR COIL
Applicant
Medrad, Inc.
Product Code
MOS · Radiology
Decision Date
Jun 18, 1998
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 892.1000
Device Class
Class 2
Indications for Use
The Medrad Neurovascular Coil is a quadrature transmit/receive coil intended to be used MRI Scanner Systems for imaging of the brain, skull base, and soft tissues of the neck and upper chest, including the carotid arteries and attendant vascular system. The Medrad Neurovascular Coil is intended for use only under the supervision of a physician who is trained in the field of Diagnostic Resonance Imaging.
Device Story
Medrad Neurovascular Coil is a quadrature transmit/receive surface coil for GE superconducting MRI scanners; facilitates imaging of intracranial/extracranial neurovasculature and skull base. Device captures hydrogen nuclei signals from head and neck anatomy (cranium to aortic arch). Operates as passive hardware component; plugs into MRI system via head coil quick disconnect port; requires no external tuning/matching. Used in clinical MRI settings by trained technicians/physicians. Output is raw MR signal processed by the host MRI scanner to produce diagnostic images. Benefits include enhanced morphological detail and improved signal-to-noise ratio (SNR) for neurovascular assessment compared to standard head or neck coils.
Clinical Evidence
Clinical evaluation compared images from the Medrad Neurovascular Coil against predicate GE Head and Anterior Neck coils. Study assessed morphological detail and SNR. Results demonstrated that the Medrad coil provides equivalent or improved image clarity and SNR for neurovascular imaging. Bench testing included NEMA-standard SNR studies, image uniformity characterization, and SAR analysis for various loading cases (lossless phantom, neck, head).
Technological Characteristics
Quadrature transmit/receive surface coil. Materials: Glass Filled Polyester (UL94-V0) housing, Buellidyne-coated comfort pads (UL-94 HFI). Connectivity: Plugs into GE MRI system via head coil quick disconnect port. No external tuning/matching required. Passive device; no internal energy source. Designed for 0.5T, 1.0T, and 1.5T MRI systems.
Indications for Use
Indicated for patients requiring MRI imaging of the brain, skull base, soft tissues of the neck, and upper chest, including carotid arteries and vascular system. Intended for use under physician supervision trained in Diagnostic Resonance Imaging.
Regulatory Classification
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).
Special Controls
*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.
Predicate Devices
General Electric (GE) Quadrature Head Coil
GE Anterior Neck Coil
Submission Summary (Full Text)
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JUN 1 8 1998
ﺴﺴﺴ
## 510(k) SUMMARY MEDRAD .5T, 1.0T, 1.5T NEUROVASCULAR COILS
OFFICIAL CONTACT: Rodney J. Rylands Regulatory Affairs Manager Medrad, Inc. One Medrad Drive Indianola, PA 15051 (412) 767-2400 Ext. 3778
CLASSIFICATION NAME: Magnetic Resonance Diagnostic Accessory[21 CFR 892.1000]
COMMON/USUAL NAME: MR Imaging Surface Coil
PROPRIETARY NAME: Medrad Neurovascular Coil
PREDICATE DEVICES:
General Electric (GE) Quadrature Head Coil and GE Anterior Neck Coil
DEVICE DESCRIPTION: The Medrad Neurovascular Coil is quadrature transmit / receive coil designed to enhance the MR Imaging of the head and neck anatomy. Reference FIGURE 1 Below:
Image /page/0/Picture/10 description: The image is a black and white line drawing of a mechanical component. The component has a cylindrical section with square cutouts, connected to a broader, flatter base. The drawing style is technical, emphasizing the component's structure and form.
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## 510(k) Summary Medrad Neurovascular Coil Device Page 2 of 4
### INTENDED USE:
The Medrad Neurovascular Coil is a quadrature transmit / receive coil intended to frome mountin the General Electric Superconducting MRI Scanners. This coil is intended to facilitate complete MR imaging of the intracranial/extracranial neurovasculature and skull base.
Head and Neck, from the top of the cranium to Anatomical Region: the arch of the aorta.
Hydrogen Nuclei Excited:
2D and 3D Imaging Diagnostic Uses:
## PROPOSED MEDRAD NEUROVASCULAR COIL TECHNICAL COMPARISON TO PREDICATE DEVICES:
The following table compares claims made in regard to the GE Head Coil, the GE Anterior Neck Coil, and the Neurovascular Coil.
| GE Head Coil | GE Anterior Neck Coil | Neurovascular Coil |
|----------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------|
| Predicated Device | Predicate Device | Proposed Device |
| Quadrature Transmit/Receive<br>Birdcage Coil | Receive-only linear coil. | Quadrature Transmit/Receive<br>coil. |
| Suggested application: Head | Anterior fossa of the skull base,<br>the orapharynx, larynx, pharynx,<br>and peripharyngealareas as well<br>as extending down through the<br>sterno-claviculararea. | Coverage extends from the top<br>of the head through the aortic<br>arch. |
| The Head Coil is compatible with<br>all Signa, Vectra and Contour<br>System pulse sequences. | The anterior neck coil is<br>compatible with all Signa and<br>Contour System pulse sequences<br>and appropriate imaging options. | The coil is compatible with all<br>Signa, and Contour pulse<br>sequences and options. |
| Each system is tuned to the<br>Head Coil. | No external tuning, or matching,<br>is necessary since the coil is<br>matched to the recommended<br>anatomy of interest. | No external tuning and matching<br>is required. |
| Plugs into MRI system by way of<br>the Head Coil quick disconnect<br>port. | The coil plugs into a common slip<br>connector. | The coil plugs into the MRI<br>system by way of the Head Coil<br>quick disconnect port. |
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510(k) Summary Medrad Neurovascular Coil Device Page 3 of 4
# PROPOSED MEDRAD NEUROVASCULAR COIL TECHNICAL COMPARISON TO PREDICATE DEVICES(Cont.):
| Patient contacting materials comparison information | | |
|------------------------------------------------------------------------------|----------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------|
| GE Head Coil | GE Anterior Neck Coil | Neurovascular Coil |
| The housing material is made from Glass Filled Polyester; Fire Rated UL94-V0 | The housing material is made from Closed Cell Polyetheylene Foam; Fire Rated UL94-HF-1 | The housing material is made from Glass Filled Polyester; Fire Rated UL94-V0 |
| The comfort pad is made of Denier Nylon Gray (Fire Rated) | No comfort pads | Comfort pads are included made with a Buellidyne coating and are fire rated UL-94 HFI. |
#### Medrad, Inc. certifies that the patient contacting materials and formulations for the Certification: proposed Medrad Neurovascular Coils are unchanged from currently marketed devices.
## PERFORMANCE TEST DATA:
## SIGNAL TO NOISE RATIO (SNR)
A Signal to Noise Ratio(SNR) study was conducted to generate a Signal -To-Noise ratio comparison between the proposed Medrad Neurovascular Coil and the predicate GE Head Coil in the Head Position and between the Neurovascular Coil and the predicate Anterior Neck Coil for the Neck location.
IMAGE UNIFORMITY - The Medrad Neurovascular Coil was evaluated using NEMA Standards to characterize the non-uniformity of the proposed coil. Contours of the images obtained with the coil were constructed for the axial image, sagittal image, and the coronal image.
SPECIFIC ABSORPTION RATE - An SAR analysis data has been gathered for the proposed Medrad Neurovascular Coil per the methodology of NEMA Standards for the following loading cases:
- 1. Lossless phantom for determination of coil losses representing a limit minimum load case.
- 2. Neck for determination of RF power deposition during Head and Neck imaging - representing a heavy load.
- 3. Head for determination of RF power deposition during Head imaging representing a light load.
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GEOMETRIC DISTORTION: The proposed Medrad Neurovascular device contains slightly magnetic materials or components. However, such components have been positioned within the surface coil so that no observable distortion of the static magnetic field is present.
TRANSMIT RF FIELD [B1] DISTORTION - Analysis of the electrical design of the coil and its blocking network demonstrates that no significant currents are induced. No artifacts of any type were observed during imaging.
RESOLUTION, SLICE THICKNESS, AND CONTRAST - These performance parameters are not affected by the use of a surface coil and were not separately tested in the performance evaluation of the proposed Medrad Neurovascular Coil.
CLINICAL EVALUATION - Images were obtained for the proposed Medrad Neurovascular Coil and the predicate GE Head Coil and GE Anterior Neck coil. The results wre compared to substantiate equivalency with regards to morphological detail and SNR.
CONCLUSION - Extensive safety, verification, durability, and clinical testing was conducted with the Medrad Neurovascular Coil to substantiate the claims of the proposed device and to verify that the proposed device is substantially equivalent to the predicate devices.
Image clarity, morphological detail and increased SNR demonstrate that the Medrad Neurovascular Coil will produce the required detailed resolution in surface coil imaqing .
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Image /page/4/Picture/0 description: The image shows the seal of the Department of Health & Human Services (HHS). The seal features a stylized eagle with three lines forming its body and wing. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circular pattern around the eagle.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
JUN 1 8 1998
Rodney J. Rylands Manager, Regulatory Affairs Medrad, Inc. One Medrad Dr. Indianola, PA 15051
Re:
K981094 Medrad 0.5T, 1.0T and 1.5T Neurovascular Coils for GE Signa MRI Systems Dated: March 24, 1998 Received: March 26, 1998 Regulatory class: II 21 CFR 892.1000/Procode: 90 MOS
Dear Mr. Rylands:
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 equivaliation assumes compliance 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 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 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/dsmamain.html".
Sincerely yours,
Lillian Yin, Ph.D.
Lillian Yin, Ph.D. Director, Division of Reproductiv Abdominal, Ear, Nose and Throa and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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1981094 510(k) NUMBER (IF KNOWN):
DEVICE NAME: Medrad Neurovascular Coil
INDICATIONS FOR USE:
The Medrad Neurovascular Coil is a quadrature transmit/receive coil intended to be used MRI Scanner Systems for imaging of the brain, skull base, and soft tissues of the neck and upper chest, including the carotid arteries and attendant vascular system.
The Medrad Neurovascular Coil is intended for use only under the supervision of a physician who is trained in the field of Diagnostic Resonance " Imaging.
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED.)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use (Per 21 CFR 801.109)
OR
Over-The-Counter-Use (Optional Format 1-2-96)
Elvin h. Sisson
(Division Sign-Off) Division of Reproductive, Abdominal, EN and Radiological D 510(k) Number
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