K990504 · C.R. Bard, Inc. · MQR · Mar 16, 2000 · General, Plastic Surgery
Device Facts
Record ID
K990504
Device Name
MEMOTHERM COLORECTAL STENT
Applicant
C.R. Bard, Inc.
Product Code
MQR · General, Plastic Surgery
Decision Date
Mar 16, 2000
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 878.3610
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
The proposed stent is indicated for the palliative treatment of colonic strictures and obstruction caused by malignant neoplasms in the rectum, sigmoid colon and descending colon.
Device Story
Memotherm Colorectal Stent is a self-expanding nitinol metal stent with flared ends; used for palliative treatment of malignant colonic strictures/obstructions. Device includes stent and coaxial delivery system with inner catheter, outer sheath, and pistol-grip handle. Physician positions device under fluoroscopic guidance after guidewire placement via colonoscope. Stent expands upon release from delivery system, exerting radial force to maintain lumen patency. Benefits include relief from partial or complete obstructions caused by colon cancer.
Clinical Evidence
No clinical data. Evidence based on published scientific literature regarding in vivo use of self-expanding metal stents for palliative treatment of colon cancer, supplemented by comparative bench testing (tensile, dimensional, trackability, deployment, expansion/compression) against the predicate device.
Technological Characteristics
Biocompatible nitinol self-expanding stent; coaxial delivery system with uni-directional pistol grip handle; radiopaque markers for positioning; available in 20-30mm diameters and 60-100mm lengths.
Indications for Use
Indicated for palliative treatment of colonic strictures and obstruction caused by malignant neoplasms in the rectum, sigmoid colon, and descending colon.
Regulatory Classification
Identification
An esophageal prosthesis is a rigid, flexible, or expandable tubular device made of a plastic, metal, or polymeric material that is intended to be implanted to restore the structure and/or function of the esophagus. The metal esophageal prosthesis may be uncovered or covered with a polymeric material. This device may also include a device delivery system.
Special Controls
The special control for this device is FDA's “Guidance for the Content of Premarket Notification Submissions for Esophageal and Tracheal Prostheses.”
Predicate Devices
WALLSTENT® Enteral Endoprosthesis
Submission Summary (Full Text)
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## MAR 1 6 2000
K 990504 1083
Bard Interventional Products Division C.R. Bard, Inc. 129 Concord Road P.O. Box 7031 Billerica, MA 01821-7031 978-663-8989
BARD
## VI 510(k) SUMMARY SAFETY AND EFFECTIVENESS INFORMATION
As required by the Safe Medical Devices Act of 1990, codified under Section 513, Part (i)(3)(A) of the Food Drug and Cosmetic Act, a summary of the safety and effectiveness information upon which substantial equivalence determination is based follows.
- A. Submitter Information
| Submitter's Name: | Bard Interventional Products Division<br>C.R. Bard, Inc. |
|----------------------|----------------------------------------------------------|
| Address: | 129 Concord Road, Bldg. #3<br>Billerica, MA 01821 |
| Phone: | 978 - 262 - 4867 |
| Fax: | 978 - 262 - 4878 |
| Contact Person: | Marion Gordon, R.A.C. |
| Date of Preparation: | December 11, 1998 |
- B. Device Name
| Trade Name: | Memotherm® Colorectal Stent |
|----------------------|------------------------------------|
| Common/Usual Name: | Expandable, metallic colonic stent |
| Classification Name: | FDA has not classified to date |
- C. Predicate Device Name
Trade Name:
WALLSTENT® Enteral Endoprosthesis Schneider (USA), Inc.
- D. Device Description:
The Memotherm® Colorectal Stent comprised of two components - a self-expanding implantable metal stent and the delivery device. The stent is a nitinol grid-like cylinder with flared ends, available in 20 and 30mm
25
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diameters and 60, 80, and 100mm lengths. While mounted on the deployment system the stent is compressed. Upon release of the stent from the deployment system the nitinol cylinder expands. The coaxial deployment system consists of an inner catheter, an outer sheath and an ergonomically shaped handgrip. Female luer injection ports are included on the back of the handgrip and ratchet carriage. Two radiopaque markers are positioned on the deployment system to mark both ends of the stent.
- Intended Use: ن
The proposed stent is indicated for the palliative treatment of colonic strictures and obstruction caused by malignant neoplasms in the rectum, sigmoid colon and descending colon.
- Technological Characteristics Summary: F.
The Memotherm® Colorectal Stent is a metal stent constructed of biocompatible nitinol. The self-expanding stent is packaged pre-mounted on a disposable delivery system that utilizes an uni-directional, pistol grip handle release mechanism.
The Memotherm® Colorectal Stent is substantially equivalent to the Schneider WALLSTENT® Enteral Endoprosthesis. Both devices are manufactured with a delivery system that implants a self-expanding metal stent over a guidewire using a coaxial, interfacing catheter/sheath (tubes). While each manufacturer's metal stents are made from different materials, both allow for self-expanding deployment using radial force to expand the inner colon lumen. The WALLSTENT can be placed via the colonoscope's working channel, while the Memotherm is positioned using fluoroscopy after the guidewire has been inserted using the colonoscope. Both manufacturers have the same intended use for the device and have stents within the same range of diameters and lengths.
- G. Performance Data
Safe and effective in vivo use of self-expanding, metal stents in the colon
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has been demonstrated in relevant published, scientific, literature. Metal stents have been shown to be effective, in palliative treatment of colon cancers, and give the patients relief from partial or complete obstructions caused by the disease.
Comparative performance testing was done, where appropriate, between the Memotherm and WALLSTENT. In addition to testing various tensile and dimensional verifications, other bench data included trackability, deployment and stent expansion/compression were completed. The stent is resistant to corrosion within the intended anatomical environment based on Bard's experience with other metal stents. All data was within the anticipated results.
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Image /page/3/Picture/2 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized eagle with three lines representing its body and wings. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular fashion around the eagle.
MAR 1 6 2000
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
Ms. Marion Gordon, R.A.C. Senior Regulatory Affairs Coordinator Bard Interventional Products Division C.R. Bard, Inc. 129 Concord Road, Bldg. #3 P.O. Box 7031 Billerica. MA 01821-7031
Re: K990504 Memotherm® Colorectal Stent
Dated: October 8, 1999 Received: October 12, 1999 Regulatory Class: III 21 CFR 878.3610/Procode: 78 MQR
Dear Ms. Gordon:
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 legally marketed predicate 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 of the Act indude 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,
CAPT Daniel G. Schultz, M.D. Acting 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): | TBD K090504 |
|---------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Device Name: | Memotherm Colorectal Stent |
| Indications For Use: | The Memotherm colorectal stent is indicated for the palliative treatment of colonic strictures and obstruction caused by malignant neoplasms in the rectum, sigmoid colon and descending colon. |
.
## (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
| Prescription Use | <div style="text-align:left;"> <div style="display:inline-block; vertical-align:middle;"></div> </div> | OR | Over-The-Counter Use | <div style="text-align:left;"> <div style="display:inline-block; vertical-align:middle;"></div> </div> |
|----------------------|--------------------------------------------------------------------------------------------------------|----|--------------------------|--------------------------------------------------------------------------------------------------------|
| (Per 21 CFR 801.109) | | | (Optional Format 1-2-96) | |
(Division Sign-Off)
Division of Reproductive, Abdominal, ENT,
and Radiological Devices
| 510(k) Number | K990504/5002 |
|---------------|--------------|
|---------------|--------------|
01
:
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.