K972879 · Imatron, Inc. · JAK · Oct 15, 1997 · Radiology
Device Facts
Record ID
K972879
Device Name
ULTRAFAST CT SCANNER; EBT CT SCANNER, EVOLUTION
Applicant
Imatron, Inc.
Product Code
JAK · Radiology
Decision Date
Oct 15, 1997
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 892.1750
Device Class
Class 2
Indications for Use
The Imatron Ultrafast CT Scanner is designed -- as are all similar devices -- to produce cross sectional images (i.e., thin slices) of the human anatomy. In this instance, such images are produced via helical (i.e., continuous volume or dynamic) or stationary (i.e., static) scanning. Imatron's device is -- as are some of the predicate devices -- also intended to be used for clinical situations requiring determination of specific quantitative information, such as the determination of calcium or other materials in bone, tumors, or organs.
Device Story
Imatron Ultrafast CT Scanner uses electron beam technology to produce X-rays; electron beam directed along tungsten target rings; electronic rotation of beam enables rapid CT slice acquisition without mechanical X-ray tube rotation. System produces cross-sectional images of human anatomy via helical or stationary scanning. Used in clinical settings for diagnostic imaging and quantitative analysis (e.g., calcium in bone, tumors, organs). High Resolution Detector (HRD) modification uses 864 pairs of contiguous detectors; odd-numbered outputs electronically delayed 60 microseconds (Time to Next Detector) and summed with even-numbered partners to improve spatial resolution. Healthcare providers use images for clinical decision-making regarding patient anatomy and pathology.
Clinical Evidence
Bench testing included approximately 61 tests for performance specifications, product acceptance, and release criteria, plus phantom testing for image quality. Clinical performance was evaluated in a study of 12 human volunteers under IRB oversight and informed consent. Results demonstrated the modified device is substantially equivalent to the predicate.
Technological Characteristics
Electron beam CT scanner; tungsten target rings; 864-pair detector array. HRD modification uses 0.125-degree detector arc width. Signal processing involves 60-microsecond electronic delay of odd-numbered detector outputs summed with even-numbered outputs. Spatial resolution: 9.5 lp/cm (5% MTF). Operates via helical or stationary scanning modes.
Indications for Use
Indicated for patients requiring cross-sectional imaging of human anatomy via helical or stationary scanning, including clinical situations requiring quantitative determination of calcium or other materials in bone, tumors, or organs.
Regulatory Classification
Identification
A computed tomography x-ray system is a diagnostic x-ray system intended to produce cross-sectional images of the body by computer reconstruction of x-ray transmission data from the same axial plane taken at different angles. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.
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Image /page/0/Picture/0 description: The image shows the word "IMATRON" in a stylized, bold font. The letters are formed by horizontal lines, giving them a futuristic or technical appearance. To the right of the word, there is a small "TM" symbol, indicating a trademark. Below the word, there is a dotted line that extends diagonally downwards.
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11972879
1 5 1997 OCT
| 510(K) SUMMARY | |
|----------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Submitter's Name: | Imatron, Inc. |
| Address: | 389 Oyster Point Blvd.<br>South San Francisco, CA 94087 |
| Phone(s): | (O) 415-583-9964, ext. 206<br>(F) 415-827-7790 |
| Contact Person: | J.A. Coduto |
| Date: | August 1, 1997 |
| Common Names: | CT Scanner; Computed Tomography X-ray System |
| Proprietary Names: | Ultrafast® CT Scanner; EBT CT Scanner, Evolution |
| Classification Name: | Computed Tomography X-ray System |
| Predicate Device: | Imatron Ultrafast CT Scanner (K913352/A) |
| Device Description: | The Imatron Ultrafast CT scanner is a scanning<br>system which operates by directing a focused beam<br>of electrons along tungsten target rings to produce<br>X-rays which pass through the body at multiple<br>angles as in conventional CT scanning systems. |
| | The Imatron Ultrafast CT scanner is capable of<br>producing CT slices at rapid speeds since the data<br>is produced by electronic rotation of the electron<br>beam itself rather than the mechanical rotation of<br>an X-ray tube as in conventional CT scanning<br>systems. |
| | Currently, the Imatron Ultrafast CT scanner<br>operating at its highest resolution mode has 864<br>single, contiguous X-ray detectors subtending an<br>arc of 0.250 degrees each. The resulting 5%<br>amplitude modulation transfer function (MTF) for<br>high contrast objects at the center of the circle of<br>reconstruction is 7 line pairs per centimeter (lp/cm). |
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### Proposed Design Modification
The primary purpose of this submission is to provide notification of a proposed design modification to the above-referenced detector system. This modification, in the aggregate, is called the High Resolution Detector (HRD). Similar to the current system, the HRD retains the original dose efficiency, the same number of data acquisition channels, and the same number of samples. It differs from the current system in that it now consists of 864 pairs of contiguous detectors subtending an arc 0.125 degree width. In the modified system odd numbered detector outputs (i.e., one half of each of the 864 pairs) are electronically delayed 60 microseconds, the time required for an object shadow to move one detector's width. This is defined by Imatron as the Time to Next Detector (TND). In the modified system each delayed output is summed with its even numbered, undelayed partner's. The resulting 5% amplitude MTF is 9.5 lp/cm.
## Other Modifications
Additionally, this notification also sets forth the numerous, nonsignificant modifications made since Imatron's last 510(k) filing with the Agency (i.e., on July 26, 1991; see K913352/A). As indicated in tables contained herein (and subsequently referenced and discussed), Imatron believes such modifications have not significantly impacted the safety, effectiveness, or intended use of the device. and, thus, they did not need to be the subject of premarket notification.
The intended use of the device here in question. i.e., the Imatron Ultrafast CT Scanner, remains unchanged from the intended use of prior predicate Imatron and other scanners. The Imatron Ultrafast CT Scanner is designed -- as are all similar devices -- to produce cross sectional images (i.e., thin slices) of the human anatomy. In this instance, such images are produced via helical (i.e., continuous
Intended Use:
406
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volume or dynamic) or stationary (i.e., static) scanning. Imatron's device is -- as are some of the predicate devices -- also intended to be used for clinical situations requiring determination of specific quantitative information, such as the determination of calcium or other materials in bone, tumors, or organs.
See attached Substantial Equivalence Comparison Technological Table and Table of Explanation of Differences. Characteristics:
In order to assure proper product performance, Non-clinical Performance: including reliability, and demonstrate substantial equivalence of the modified scanner here in question to the predicate scanner, the modified scanner was extensively bench tested. Such finished testing included approximately 61 tests to determine conformance with n numerous performance specifications, including four product acceptance tests and 12 product release criteria tests. Also included was phantom testing to assure the requisite quality of the finished X-ray product.
- Clinical Performance: After successfully completing bench testing such modified device was then used for human volunteer testing - pursuant to IRB overview and informed consent. Such testing was conducted on site, and incorporated use of twelve human subjects. Again, the device was demonstrated to be substantially equivalent.
- Testing Conclusions: The above-referenced tests indicated that the device as modified is substantially equivalent to the predicate device.
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Image /page/3/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of 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 or bird-like figure with three stylized lines representing its wings or body. The logo is black and white.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
OCT 1 5 1997
J.A. Coduto Director, Regulatory Affairs Imatron, Inc. 389 Oyster Point Blvd. South San Francisco, CA 94080 Re: K972879
Ultrafast Computed Tomography Scanner Models C-150XP and C-150LXP with High Resolution Detector Dated: August 4, 1997 Received: August 5, 1997 Regulatory class: II 21 CFR 892.1750/Procode: 90 JAK
#### Dear Mr. Coduto:
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, 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 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 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 (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.D.Liau 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
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#### D. PROPOSED INTENDED USE STATEMENT
The intended use of the device here in question, i.e., the Imatron Ultrafast CT Scanner, remains unchanged from the intended use of prior predicate Imatron and other scanners. The Imatron Ultrafast CT Scanner is designed -- as are all similar devices -- to produce cross sectional images (i.e., thin slices) of the human anatomy. In this instance, such images are produced via helical (i.e., continuous volume or dynamic) or stationary (i.e., static) scanning. Imatron's device is -- as are some of the predicate devices -- also intended to be used for clinical situations requiring determination of specific quantitative information, such as the determination of calcium or other materials in bone, tumors, or organs.
David b. Sijmm
(Division Sign-Off) (Division Sign-Off)
Division of Reproductive, Abdominal, ENT, and Radiological Devices 510(k) Number
Prescription Use
(Per 21 CFR 801.109)
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