K974438 · Medrad, Inc. · MOS · Apr 30, 1998 · Radiology
Device Facts
Record ID
K974438
Device Name
MEDRAD ATD-T INTERFACE DEVICE
Applicant
Medrad, Inc.
Product Code
MOS · Radiology
Decision Date
Apr 30, 1998
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 892.1000
Device Class
Class 2
Indications for Use
The purpose of the ATD-T is to provide interface and support functions to allow the use of Medrad disposable endorectal coils with the GEMS Signa 1.5 Tesla MRI Scanner System and Torso Array Coil. The use of the ATD-T is a requirement whenever MR imaging is to be performed using the GEMS Signa 1.5 Tesla MRI System with the Torso Array Coil and any of the Medrad family of disposable endorectal coils. Use of the ATD-T is indicated with all 1.5 Tesla Endorectal Coils.
Device Story
Interface device for MRI systems; enables use of Medrad disposable endorectal coils with GEMS Signa 1.5T MRI scanner and Torso Array Coil. Hardware consists of two electronic units: input port housing with PCB attached to Torso Array posterior cable; external unit between Torso Array output and system Phased Array port. Functions: tuning, impedance matching to 63.87 MHz Larmour frequency; decoupling endorectal coils during RF excitation; signal combining from Torso Array posterior elements. Used in clinical imaging environments; operated by MRI technicians/radiologists. Durable design; 3,000-procedure lifespan. Ensures compatibility between endorectal coils and MRI scanner; maintains signal-to-noise ratio (SNR) performance; facilitates diagnostic imaging of prostate, cervix, and colon.
Clinical Evidence
Bench testing only. Evaluated using NEMA Standard No. 6 for special purpose coils. SNR performance compared against predicate GE 1.5T ATD-III using loaded phantoms and identical scan parameters. Results verified equivalent or increased SNR. No clinical data provided; laboratory testing confirmed no adverse effect on image performance of endorectal coils, GE Torso Array, or GE MRI system.
Technological Characteristics
Electronic interface device; includes PCB and external signal-combining unit. Operates at 1.5 Tesla (63.87 MHz). Features internally selectable circuitry for compatibility with different GEMS/Gore Torso Array versions (IEC-601 First Fault detection compliant). Durable construction; 5-year/3,000-procedure service life. Passive electronic components for tuning, impedance matching, and decoupling.
Indications for Use
Indicated for patients undergoing MR imaging of the prostate gland, cervix, or colon using Medrad disposable endorectal coils and GEMS Signa 1.5 Tesla MRI systems.
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
GE 1.5T ATD-III
Submission Summary (Full Text)
{0}
MEDRAD®
APR 30 1998
QA-97-1232
510(k) SUMMARY
**MEDRAD 1.5T ATD-T**
K974438
| OFFICIAL CONTACT: | Mary Ann Greenawalt, J.D.
Sr. Regulatory Affairs Associate
Medrad, Inc.
One Medrad Drive
Indianola, PA 15051 |
| --- | --- |
| CLASSIFICATION NAME: | Magnetic Resonance Diagnostic Accessory
[21 CFR 892.1000] |
| COMMON/USUAL NAME: | MRI System Interface Device |
| PROPRIETARY NAME: | Medrad 1.5T ATD-T |
| PREDICATE DEVICES: | GE 1.5T ATD-III |
**DEVICE DESCRIPTION:**
The Medrad Magnetic Resonance Endorectal Imaging System consists of a disposable, receive only endorectal coil for MR imaging of the male prostate gland and associated anatomy, or other target region of interest, including the cervix and colon. The Medrad ATD-T provides the interface, decoupling, and support functions required to successfully operate the endorectal coils with the GEMS Signa MRI Scanner System with Phased Array capability, and the GEMS Torso Array Coil operating at 1.5 Tesla. The ATD-T consists of two electronic devices, a printed circuit board installed in an Input Port housing attached to the Torso Array Coil posterior cable, and an external unit placed between the Torso Array Coil output cable and the system Phased Array Coil Port. This hardware is intended for repeated use with suitable Medrad disposable MRI Endorectal Coils. The ATD-T sets the tuning and impedance matching of a nominal endorectal coil to the nominal system Larmour frequency, 63.87 MHz for the GEMS Signa 1.5 Tesla MRI System.
The electronic components required to provide effective decoupling disposable endorectal coils resonant response from the MRI RF excitation field during the transmit portion of the MR imaging pulse sequence are included in the ATD-T Input Port Unit.
QA-97-1232
{1}
MEDRAD
QA-97-1232
The ATD-T External Unit combines the signal from the two posterior coil elements of the Torso Array coil to drive a single Phased Array Coil Port, making one Port available for the output of the endorectal coil. It includes internally selectable circuitry to enable it to be used with either the current version of the GEMS/Gore Torso Array Coil [using PA Ports 3, 4, 5, and 6], or the future version designed to meet IEC-601 First Fault detection conditions [using PA Ports 2, 4, 5, and 7].
The ATD-T is designed as a durable item with an expected life of at least three thousand procedures, equivalent to at least five years of service. The specific application of this version of the ATD-T involves MR imaging at 1.5 Tesla, using a Medrad disposable endorectal coil, and a GEMS Signa 1.5 Tesla MRI System including the GEMS Phased Array feature and the Torso Array Coil.
## INTENDED USE:
The purpose of the ATD-T is to provide interface and support functions to allow the use of Medrad disposable endorectal coils with the GEMS Signa 1.5 Tesla MRI Scanner System and Torso Array Coil. The use of the ATD-T is a requirement whenever MR imaging is to be performed using the GEMS Signa 1.5 Tesla MRI System with the Torso Array Coil and any of the Medrad family of disposable endorectal coils. Use of the ATD-T is indicated with all 1.5 Tesla Endorectal Coils.
## PERFORMANCE TEST DATA:
### Signal to Noise Ratio (SNR)
The Medrad 1.5T ATD-T was evaluated using National Electric Manufacturer’s Association (NEMA) Standard No. 6, Characterization of Special Purpose Coils for Diagnostic Magnetic Resonance Images.
Both the Medrad 15T ATD-T and the predicate GE ATD-III were evaluated with a loaded phantom to determine the SNR for both coils. The coils were evaluated using the same scan parameters to produce identical images. The results were compared to verify the equivalent or increased SNR of the proposed coil.
### Image Uniformity Testing:
Not Applicable. No uniformity claims are made for this device.
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{2}
MEDRAD
QA-97-1232
## Clinical Testing:
Medrad has demonstrated with Laboratory testing that the proposed Medrad 1.5T ATD-T does not affect the image performance of the Medrad Endorectal Coils, the GE Torso Array, or the GE MRI System. No claims for enhanced images are made herein.
**SAR**: Not applicable.
## CONCLUSION:
Extensive safety, verification, durability, and clinical testing was conducted with the Medrad 1.5T ATD-T to substantiate the claims of the proposed device and to verify that the proposed device is substantially equivalent to the predicate device.
E
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DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
Food and Drug Administration
9200 Corporate Boulevard
Rockville MD 20850
APR 30 1998
Jim Ferguson, Jr.
Sr. Regulatory Affairs Associate
Medrad, Inc.
One Medrad Drive
Indianola, PA 15051
Re: K974438
Medrad ATD-T Interface Device
Dated: March 23, 1998
Received: March 24, 1998
Regulatory class: II
21 CFR 892.1000/Procode: 90 MOS
Dear Ms. Greenwalt:
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 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 requirements, 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 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/cdrh/dsma/dsmamain.html".
Sincerely yours,
Enclosure
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MEDRAD®
# INDICATIONS FOR USE
The purpose of the ATD-T is to provide interface and support functions to allow the use of Medrad disposable endorectal coils with the GEMS Signa 1.5 Tesla MRI Scanner System and Torso Array Coil. The use of the ATD-T is a requirement whenever MR imaging is to be performed using the GEMS Signa 1.5 Tesla MRI System with the Torso Array Coil and any of the Medrad family of disposable endorectal coils. Use of the ATD-T is indicated with all 1.5 Tesla Endorectal Coils.
*Medrad, Inc.*
One Medrad Drive
Indianola, PA 15051-0780
(412) 767-2400
*David H. Sagem*
(Division Sign-Off)
Division of Reproductive, Abdominal, ENT, and Radiological Devices
510(k) Number **8974438**
Prescription Use ☑
(Per 21 CFR 801.109)
Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.
