The TREX MRI system produces cross-sectional images: Anatomical Region: General body anatomy, including head, spine, forso, and extremities 1H nuclei (Proton) Nucleus excited: . Images correspond to the distribution of 1H nuclei exhibiting Diagnostic uses: . nuclear magnetic resonance, with image intensity dependent upon NMR parameters, including spin-lattice relaxation time (T1) spin-spin relaxation time (T2) density of nuclei (p) flow velocity chemical shift (δ) lmages may be interpreted by a trained physician to yield Clinical use: . information that can be useful in the determination of a diagnosis.
Device Story
TREX MRI (formerly IMiG-MRI) is a 0.15T magnetic resonance diagnostic device. System utilizes RF coils (Head, C-Spine, Knee) to capture 1H nuclei signals; transforms signals into cross-sectional images based on T1, T2, proton density, flow velocity, and chemical shift. Operated by trained clinicians in stationary clinical settings. Output consists of diagnostic images interpreted by physicians to assist in clinical diagnosis. Device enhancements include quadrature Head and C-Spine coils and a linear Knee coil to improve SNR and coil fill factor. System supports multiple acquisition sequences: Spin Echo, Gradient Echo, Fast Spin Echo, Fast Dual Echo, 3D Fast Gradient Echo, and Inversion Recovery. No software revisions required for coil integration.
Clinical Evidence
Bench testing only. Performance parameters provided for the new RF coils, including SNR (>34.2 for Head coil), uniformity (<14% for Head coil), and geometric distortion (<2.5% for Head coil). No clinical data presented.
Technological Characteristics
0.15T static magnetic field; 18.4 T/sec max field change; 0.05W/kg RF power deposition. RF coils: quadrature Head (19cm diameter), quadrature C-Spine, linear Knee. Imaging sequences: Spin Echo, Gradient Echo, Fast Spin Echo, Fast Dual Echo, 3D Fast Gradient Echo, Inversion Recovery (STIR, FLAIR).
Indications for Use
Indicated for patients requiring cross-sectional imaging of general body anatomy, including head, spine, torso, and extremities, using 1H nuclei nuclear magnetic resonance parameters (T1, T2, density, flow, chemical shift) for diagnostic purposes.
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.
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# Attachment 1 510(k) Summary of Safety and Effectiveness
Back to Table of Contents
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#### SUBMITTER INFORMATION: 1.0
- Field Effects, a division of Intermagnetics General Corporation 1.1 · Submitter: 300 Vesper Executive Park Tynasborough, MA 01879 PH: 978 649-8590 FX: 978 649-8520 Email: GHURST@IGC.com
- Grea Hurst, Ph.D. 1.2 Contact: Mgr., Imaging Science and Applications
- June 10, 1998 1.3 Date:
- Regulatory Counsel: 1.4 Jonathan S. Kahan, Attorney at Law Hoaan & Hartson 555 Thirteenth St. NW Washington, DC 20004-1109 PH: 202 637-5794 FX: 202 637-5910
#### DEVICE NAME: 2.0
- Radiology Classification Panel: 2.1
- 892.1000 Maanetic Resonance Diagnostic Device Classification Number: 2.2
- System, Nuclear Magnetic Resonance Imaging 2.3 Product Nomenclature:
- Product Code(s): 90LNH 2.4
- 90MOS (Maanetic Resonance Specialty Coil)
- 2.5 Trade/Proprietary Name: TREX MRI
- IMiG-MRI 2.6 Predicate Device:
#### DEVICE DESCRIPTION: 3.0
#### 3.1 FUNCTION
Identical to the IMiG-MRI 510(k) K963953. As a result of newly created business arrangements, the original IMiG-MRI system will now be renamed as TREX MRI. With the exception of the device modifications identified in this 510(k) submission, and the renaming of the product, the TREX MRI is identical to the original IMiG-MRI system.
The TREX MRI 0.15T Elliptical MRI Magnetic Resonance Diagnostic Device is being enhanced by three additional RF Coils (Head Coil [quadrature], C-Spine Coil [quadrature], and Knee Coil [linear]) to increase the clinical utility of the TREX MRI in the stationary configuration.
The new quadrature Head Coil (Field Effects P/N 96530-01) will have a smaller diameter of 19 cm. The reduction in diameter will allow for improved coil fill factor, increasing SNR, while maintaining optimal coil uniformity. This new coil will replace the original Head Coil.
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The new C-Spine Coil Field Effects P/N 96529-01) is substantially re-designed from the original coil, optimized for Cervical Spine imaging, and reducing the potential for patient anxiety and claustrophobia. This new coil utilizes a proprietary multiple receiver coil design, and will replace the original C-Spine/Knee Special Purpose Coil.
The new Knee Coil (Field Effects P/N 96629-01) utilizes a proprietary solenoid receiver coil design optimized for knee and extremity anatomies, improving coil fill factor, and increased S/N Ratio.
TREX MRI software did not need to be revised in order to support full functionality of these coils.
#### 3.2 Safety Parameter Summary
| Maximum static magnetic field | 0.15 Tesla |
|------------------------------------------|---------------------------------|
| Maximum rate of magnetic field<br>change | 18.4 Tesla/sec |
| Maximum RF power deposition | 0.05W/kg |
| Acoustic noise levels | 114dB peak; 95dB A-weighted RMS |
#### 3.3 Performance Parameter Summary
| Receiver Coil | Head | Body |
|----------------------|------------------------------------------|----------|
| Specification Volume | 15cm dsv | 30cm dsv |
| SNR | > 34.2 | > 33.1 |
| Uniformity | < 14% | < 40% |
| Geometric Distortion | < 2.5% | < 3.5% |
| Slice Thickness | within 10% of nominally designated value | |
| Slice Position | within 10% of nominally designated value | |
| Spatial resolution | nominally equivalent to pixel size | |
#### General Safety and Effectiveness Summary 3.4
Safe and effective use of the machine is assured by associated labeling. This labeling includes: advertising brochures, Site Planning Guide, and Instructions for Use (comprised of Clinical Users Guide, User Safety Guide, User Training Guide, User Applications Guide, and User QA & Maintenance Guide).
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#### DEVICE INTENDED USE: 4.0
The TREX MRI system produces cross-sectional images:
diaqnosis
- · Anatomical Region: General body anatomy, including head, spine, forso, and extremities
- 1H nuclei (Proton) Nucleus excited: .
- Images correspond to the distribution of 1H nuclei exhibiting Diagnostic uses: . nuclear magnetic resonance, with image intensity dependent upon NMR parameters, including spin-lattice relaxation time (T1) spin-spin relaxation time (T2) density of nuclei (p) flow velocity chemical shift (δ) lmages may be interpreted by a trained physician to yield Clinical use: . information that can be useful in the determination of a
### DEVICE TECHNOLOGICAL CHARACTERISTICS: 5.0
Identical to the Predicate Device.
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Image /page/4/Picture/2 description: The image shows the address of the Food and Drug Administration. The address is 9200 Corporate Boulevard, Rockville MD 20850. The text is black and the background is white.
SEP
2 1998
Greg Hurst, Ph.D. Mgr., Imaging Science and Applications Field Effects, A Division of Intermagnetics General Corp. 300 Vesper Executive Park Tyngsborough, Massachusetts 01879
Re:
K982157
TREX Magnetic Resonance Diagnostic Device Dated: June 10, 1998 Received: June 19, 1998 Regulatory Class: II 21 CFR 892.1000/Procode: 90 LNH
Dear Dr. Hurst:
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, 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 (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 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/dsmaldsmam.html".
Sincerely yours,
Kilian Yin, Ph.D.
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): TREX MRI MAGNETIC RESONANCE DIAGNOSTIC DEVICE+ Device Name: SUPPLEMENTAL RF COILS Indications for Use: The TREX MRI system produces cross-sectional images:
- Anatomical Region: General body anatomy, including head, spine, forso, and ●
- extremities 1 H nuclei (Proton) Nucleus excited: ● Images correspond to the distribution of 1H nuclei exhibiting Diagnostic uses: nuclear magnetic resonance, with image intensity dependent upon NMR parameters, including - spin-lattice relaxation time (TT) - spin-spin relaxation time (T2) - density of nuclel (p) - flow velocity - chemical shift (8) Images may be interpreted by a trained physician to yleld Clinical use: . information that can be useful In the determination of a diagnosis. Head - quadrature ● RF Coils: Cervical Spine - quadrature Lumbar Spine, Thoracic Spine, and Abdomen - quadrature Knee - linear Spin Echo Image Acquisition . Gradient Echo (GE,RGE) Fast Spin Echo (FSE) Fast Dual Echo (FDE) 3D Fast Gradient Echo (3DGE, 3DRGE) Inversion Recovery with Fast Spin Echo (FSE STIR, FSE FLAIR)
(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
(Division Sign-Off)
Division of Reproductive, Abdominal, ENT,
and Radiological Devices
510(k) Number K982157
Prescription Use
(Per 21 CFR 801-109
OR
Over-the-Counter Use
(Optional Format 1-2-96) Back to Table of Contents
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Learn the FDA Browser
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.