HITACHI STRATIS, MRH-1500 MAGNETIC RESONANCE DIAGNOSTIC DEVICES VERSION 6 OPERATING SYSTEM SOFTWARE
K961969 · Hitachi Medical Systems America, Inc. · LNH · Sep 5, 1996 · Radiology
Device Facts
Record ID
K961969
Device Name
HITACHI STRATIS, MRH-1500 MAGNETIC RESONANCE DIAGNOSTIC DEVICES VERSION 6 OPERATING SYSTEM SOFTWARE
Applicant
Hitachi Medical Systems America, Inc.
Product Code
LNH · Radiology
Decision Date
Sep 5, 1996
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 892.1000
Device Class
Class 2
Indications for Use
The MR system is an imaging device, and is intended to provide the physician with physiological and clinical information, obtained non-invasively and without the use of ionizing radiation. The MR system produces transverse, coronal, sagittal, oblique, and curved cross-sectional images that display the internal structure of the head, body, or extremities. The images produced by the MR system reflect the spatial distribution of protons (hydrogen nuclei) exhibiting magnetic resonance. The NMR properties that determine the image appearance are proton density, spin-lattice relaxation time (T1), spin-spin relaxation time (T2), and flow. When interpreted by a trained physician, these images provide information that can be useful in diagnosis determination.
Device Story
Version 6 Operating System Software update for Hitachi STRATIS/MRH-1500 MRI systems; enhances clinical utility via new imaging sequences and post-processing. Inputs: RF signals from hydrogen nuclei in magnetic field; spatial localization via magnetic field gradients. Processing: RF excitation, gradient application, echo measurement, image reconstruction. New features: RF spoiling, SSP for 3D MRA, RF Fat Suppression, MTC background suppression, 3D-FSE, 3D-FIR, rephased 2D-FSE/2D-GFE, 2D-FIR Dual Contrast, RF coil uniformity correction, adaptive image post-processing. Output: 2D/3D cross-sectional anatomical images. Used in clinical settings by physicians for diagnostic interpretation. Benefits: high-quality anatomical imaging without ionizing radiation; improved contrast and MRA capabilities.
Clinical Evidence
Bench testing only. No clinical data provided.
Technological Characteristics
Software-based operating system update for MRI. Imaging sequences: SE, SES, FSE, IR, FIR, GFE, RS. Post-processing: RF coil uniformity, adaptive image processing. Operates on existing Hitachi STRATIS/MRH-1500 hardware. Magnetic field strength up to 1.5T. RF frequencies up to 65MHz.
Indications for Use
Indicated for patients requiring non-invasive diagnostic imaging of the head, body, spine, and extremities to visualize internal structures based on proton density, T1, T2, and flow characteristics.
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
Hitachi STRATIS with Version 3 Operating System Software
Hitachi MRH-1500 with Version 3 Operating System Software
Submission Summary (Full Text)
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K961969
SEP 5 1996
## Attachment 1
## 510(k) Summary of Safety and Effectiveness
Page 9
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K961969
## 1.0 SUBMITTER INFORMATION:
1.1 Submitter: Hitachi Medical Systems America
1963 Case Parkway
Twinsburg, OH 44087
PH: 216 425-1313
FX: 216 425-1410
1.2 Contact: James Jochen Rogers
1.3 Date: May 15, 1996
## 2.0 DEVICE NAME:
2.1 Magnetic Resonance Diagnostic Device
2.2 Classification Name: System, Nuclear Magnetic Resonance Imaging
2.3 Classification Number: 90LNH
2.4 Trade/Proprietary Name: Version 6 Operating System Software
2.5 PREDICATE DEVICE(s):
Hitachi STRATIS with Version 3 Operating System Software
Hitachi MRH-1500 with Version 3 Operating System Software
## 3.0 DEVICE DESCRIPTION:
3.1 FUNCTION
The STRATIS / MRH-1500 Operating System Software is revised to Version 6 to increase the clinical utility of the STRATIS / MRH-1500 in the stationary configuration.
Version 6 Operating System revisions include the addition of RF spoiling, SSP for enhanced 3D MRA, RF Fat Suppression, MTC for background suppression, 3D-FSE, 3D-FIR, rephase added to 2D-FSE and 2D-GFE, 2D-FIR Dual Contrast, RF coil uniformity image post-processing, and adaptive image post-processing.
3.2 SCIENTIFIC CONCEPTS
Magnetic Resonance (MR) is based on the fact that certain atomic nuclei have electromagnetic properties which cause them to act as small spinning bar magnets. The most ubiquitous of these nuclei is hydrogen, which makes it the primary nucleus used in current imaging experiments in magnetic resonance. When placed in a magnetic field, there is a slight net orientation or alignment of these atomic nuclei with the magnetic field. The introduction of a short burst of radiofrequency (RF) excitation of wavelength specific to the magnetic field strength and to the atomic nuclei under consideration can cause a reorientation of the proton's magnetization vector. When the RF excitation is removed, the proton relaxes and returns to its original orientation. The rate of relaxation is exponential, and varies with the character of the proton and its adjacent molecular environment. This reorientation process is characterized by two exponential relaxation times called T1 and T2 which can be measured.
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These relaxation events are accompanied by an RF emission or echo which can be measured and used to develop a representation of these emissions on a three dimensional matrix. Spatial localization is encoded into the echo by varying the RF excitation and by appropriately applying magnetic field gradients in x, y, and z directions, and changing the direction and strength of these gradients. Images depicting the spatial distribution of NMR characteristics of the nuclei under consideration can be constructed by using image processing techniques similar to those used in CT.
For magnetic fields up to 1.5T, the RF frequencies commonly used range up to 65MHz. The RF fields have pulse powers from several watts to greater than 10 kilowatts, and repeat at rates from once every few seconds to greater than fifty per second. The time-varying magnetic gradient fields have a typical duration of sub-millisecond to several milliseconds.
### 3.3 PHYSICAL AND PERFORMANCE CHARACTERISTICS
MR is currently of great interest because it is capable of producing high quality anatomical images without the associated risks of ionizing radiation. In addition, the biological properties that contribute to MR image contrast are different from those responsible for x-ray image contrast. In x-ray imaging, differences in x-ray attenuation, largely based on differences in electro density are responsible for the contrast observed in x-ray images. In MR imaging, differences in proton density, blood flow, and relaxation times T1 and T2 all may contribute to image contrast. In addition, by varying the duration and spacing of the RF pulses, images may be produced in which the contrast is primarily dependent on T1 relaxation, T2 relaxation, proton density, or a combination of all three.
### 4.0 DEVICE INTENDED USE:
The MR system is an imaging device, and is intended to provide the physician with physiological and clinical information, obtained non-invasively and without the use of ionizing radiation. The MR system produces transverse, coronal, sagittal, oblique, and curved cross-sectional images that display the internal structure of the head, body, or extremities. The images produced by the MR system reflect the spatial distribution of protons (hydrogen nuclei) exhibiting magnetic resonance. The NMR properties that determine the image appearance are proton density, spin-lattice relaxation time (T1), spin-spin relaxation time (T2), and flow. When interpreted by a trained physician, these images provide information that can be useful in diagnosis determination.
- Anatomical Region: Head, Body, Spine, Extremities
- Nucleus excited: Proton
- Diagnostic uses: 2D T1- / T2-weighted imaging T1, T2, proton density measurements MR Angiography image processing
- Imaging capabilities: 2D, 3D Spin Echo (SE) 2D Short Spin Echo (SES) 2D, 3D Fast Spin Echo (FSE) 2D Inversion Recovery (IR) 2D, 3D Fast Inversion Recovery (FIR) 2D,3D Gradient Field Echo (GFE); also with rephasing 2D, 3D Rapid Scan (RS) MTC, RF Spoiling
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MR Angiography, (2D INFA, 3D INFA, 2D GFEA, 3D GFEA, Sloped Slab Profile (SSP))
RF Coil Uniformity
Adaptive Image post-processing
## 5.0 DEVICE TECHNOLOGICAL CHARACTERISTICS:
Identical to the Predicate Device.
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.
