K984235 · International Brachytherapy, Inc. · KXK · Jun 9, 1999 · Radiology
Device Facts
Record ID
K984235
Device Name
INTERSOURCE 125, MODEL 1251L
Applicant
International Brachytherapy, Inc.
Product Code
KXK · Radiology
Decision Date
Jun 9, 1999
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 892.5730
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
InterSource125 implants are indicated for interstitial implantation of select localized tumors with low to moderate radiosensitivity. They are used either as primary treatment for tumors such as those of the head, lung, neck, pancreas, prostate, and unresectable tumors, or for residual disease after excision of the primary tumor. InterSource125 implants are indicated for use concurrent with or at the completion of other treatment modalities, such as external beam radiation therapy.
Device Story
InterSource125 is a hermetically sealed, titanium-encapsulated Iodine-125 (I-125) brachytherapy seed; used for interstitial implantation in localized tumors. Device consists of an inner titanium tube containing I-125 and a platinum/iridium radiopaque marker, sealed within an outer titanium tube via laser welding. Implanted by physicians into tumor sites; radiation emitted by I-125 provides localized therapeutic dose to tumor tissue. Benefits include targeted radiation delivery to tumors of head, neck, lung, pancreas, and prostate, minimizing exposure to surrounding healthy tissue. Device is a passive radioactive source; no electronic processing or software involved.
Clinical Evidence
No clinical data provided. Substantial equivalence established via bench testing comparing physical dimensions, material composition, and radiation dose distribution profiles against the predicate device.
Technological Characteristics
Hermetically sealed brachytherapy seed; medical grade titanium construction; platinum/iridium radiopaque marker; Iodine-125 radioisotope; 4.5 mm length, 0.8 mm outside diameter; laser-welded seal; passive radioactive source.
Indications for Use
Indicated for interstitial implantation of localized tumors (head, lung, neck, pancreas, prostate, unresectable) with low to moderate radiosensitivity; used as primary treatment or for residual disease post-excision; can be used concurrently or following external beam radiation therapy.
Regulatory Classification
Identification
A radionuclide brachytherapy source is a device that consists of a radionuclide which may be enclosed in a sealed container made of gold, titanium, stainless steel, or platinum and intended for medical purposes to be placed onto a body surface or into a body cavity or tissue as a source of nuclear radiation for therapy.
Special Controls
*Classification.* Class II (special controls). A prostate seeding kit intended for use with a radionuclide brachytherapy source 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
Amersham/Medi+Physics Model 6711 Therapeutic Seed Source (K914281)
Submission Summary (Full Text)
{0}------------------------------------------------
| IBt | | | | November 24, 1998 | | Page 16 of 19 |
|--------------------------|------------------------------------------|------------------------------------|-----------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--|---------------|
| Title: | Premarket Notification -- InterSource125 | | | | | |
| | | | | | | K984235 |
| 8 | 510(K) SUMMARY | | | | | |
| 8.1 | General Information | | | | | |
| Applicant: | | | IBt, Inc. | 6000 Live Oak Parkway, Suite 107<br>Norcross, GA 30093 | | |
| | | | Tel: | (770) 582 0662 | | |
| | | | Fax: | (770) 582 0657 | | |
| | Contact Person IBt, Inc.: | | | Ruth Feicht | | |
| | | Establishment Registration Number: | | 9035105 (IBt, Inc.) | | |
| | Manufacturing Site: | | IBt SA | Zone Industrielle C<br>7180 Seneffe - Belgium | | |
| | | | Tel: | (+32) 64 / 520 811 | | |
| | | | Fax: | (+32) 64 / 520 801 | | |
| | Contact Person IBt SA: | | | Vincent Coniglione | | |
| | | Establishment Registration Number: | | 9031509 (IBt SA) | | |
| | Classification Name: | | | Radionuclide Brachytherapy Source | | |
| | Common/Usual Name: | | | Iodine-125 Seed | | |
| | Proprietary Name: | | | InterSource125 (InterSource125 is a Trademark of IBt SA.) | | |
| | Model Number: | | | 1251L | | |
| | | Establishment Registration Number: | | 9035105 (IBt, Inc.) | | |
| | Classification: | | | Class II, same as the predicate device (see the Substantial<br>Equivalence section below for predicate device information) | | |
| Special Controls: | | | | InterSource125 will comply with the regulatory requirements for the<br>Georgia Department of Natural Resources, Environmental Protection<br>Division, Radioactive Materials Division for sealed brachytherapy<br>implant sources. | | |
| Substantial Equivalence: | | | | InterSource125 is substantially equivalent to the<br>Amersham/Medi+Physics Model 6711 Therapeutic Seed Source<br>(Premarket Notification #K914281), a Class II post-amendment device<br>granted clearance to market on 22 Nov 1991. | | |
| 8.2 | | | | The contents of this premarket notification summary will demonstrate the<br>substantial equivalence of the subject device, InterSource125, to the predicate<br>device, the Amersham/Medi+Physics Model 6711 Therapeutic Seed Source.<br>The substantial equivalence will be based on the following important features of<br>the device: | | |
| | 8.2.1 | Indications | | | | |
| | 8.2.2 | Physical Size | | | | |
| | 8.2.3 | Radiopaque Marker | | | | |
| | 8.2.4 | Biocompatibility | | | | |
| | 8.2.5 | Radioisotope | | | | |
{1}------------------------------------------------
| <i>IBt</i><br>November 24, 1998 | | | Page 17 of 19 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--|---------------|
| Title: Premarket Notification - InterSource125 | | | |
| 8.3 InterSource125 Description | | | |
| InterSource125 is a hermetically sealed radiotherapeutic source indicated<br>for interstitial implantation. The radionuclide used in InterSource125 is<br>lodine-125 (I-125). InterSource125 is constructed by placing a platinum /<br>iridium radiopaque marker and I-125 on the surface of a medical grade<br>titanium inner tube. The device is sealed by sliding an outer tube, also<br>medical grade titanium, over the inner tube and laser welding both ends.<br>The resulting device has a hollow center with an inner diameter of 0.37<br>mm with all body tissue contacting surfaces made from medical grade<br>titanium. | | | |
| 8.4 Table 6 compares the indications statement drafted for InterSource125 with the<br>predicate device's indications statement. | | | |
| Table 6: Indications Statement Comparison Summary | | | |
| InterSource125 | Predicate Device | | |
| InterSource125 implants are indicated for<br>interstitial implantation of select localized<br>tumors with low to moderate radiosensitivity.<br>They are used either as primary treatment | I-125 Seeds are indicated for interstitial treatment of<br>tumors which have the following characteristics:<br>unresectable, localized, slow growth rate, and low to<br>moderate radiosensitivity. I-125 Seeds may be used to | | |
| for tumors such as those of the head, lung | treat superficial, intraabdominal or intrathoracic | | |
## InterSource125 is substantially equivalent to the predicate device with respect to its indications. 8.6 Table 7 compares the physical size, radiopaque marker, materials of construction, and the radioisotope for the subject device and the predicate
Based on the intent of the indications statement for the subject device,
neck, pancreas, prostate, and unresectable
tumors, or for residual disease after excision
implants are indicated for use concurrent
with or at the completion of other treatment
modalities, such as external beam radiation
of the primary tumor. InterSource125
therapy.
device.
8.5
| Feature Description | InterSource125 | Predicate Device |
|---------------------|------------------------|------------------|
| Outer Tube | Medical grade titanium | Titanium |
| Length | 4.5 mm | 4.5 mm |
| Outside Diameter | 0.8 mm | 0.8 mm |
| Radiopaque Marker | Platinum / Iridium | Silver |
| Isotope Carrier | Medical grade titanium | Silver |
| Inner Tube | Medical grade titanium | Not Applicable |
| Seal Method | Laser Weld | Plasma Arc Weld |
| Radioisotope | Iodine-125 | Iodine-125 |
tumors. Tumors of the head, neck, lung, pancreas,
125 Seeds are indicated to treat residual tumors
therapy. In addition, recurrent tumors may be
implanted with I-125 Seeds.
and prostate (early stages) are commonly treated. I-
following completion of a course of external radiation
{2}------------------------------------------------
IBt
November 24, 1998
Premarket Notification - InterSource125 Title:
| Half-life | 59.4 days | 59.4 days |
|-----------------------------|------------------------------------------------------|------------------------------------------------------|
| Principal Energy | 27.2 keV, 27.5 keV | 27.2 keV, 27.5 keV |
| Levels | 31.0 keV, 35.5 keV | 31.0 keV, 35.5 keV |
| Distribution of Isotope | Deposited onto the surface<br>of the isotope carrier | Deposited onto the surface<br>of the isotope carrier |
| Apparent Activity<br>Levels | 0.1 to 5.0 mCi | 0.18 to 5.99 mCi |
| Residual Activity | < 1.1 µCi at 2 years | < 1.3 µCi at 2 years |
8.7 Based on the outside dimensions of the subject device being the same as the predicate device, both devices having a radiopaque marker, the body tissue contacting materials being made of a known biocompatible material, titanium, and both devices using lodine-125 as the radionuclide, the subject device, InterSource125 is substantially equivalent to the predicate device with respect to the physical size, presence of a radiopaque marker, biocompatibility, and radioisotope used.
- The radiation dose of InterSource125 and the therapeutic effect of the ionizing 8.8 radiation emitted are characteristics of the radionuclide used, lodine-125, and the shape and placement of the internal components. Figure 5 shows the computed values for the radiation dose delivered by InterSource125 and the measured values for the radiation dose delivered by the predicate device (as previously published) as a function of angle.
Image /page/2/Figure/7 description: The image is a polar plot comparing two different devices, "InterSource125" and "Predicate Device". The plot shows the radiation pattern of each device, with the angle in degrees around the circle and the magnitude of the radiation along the radial axis. The "InterSource125" is represented by a solid line, while the "Predicate Device" is represented by a dashed line. The plot also includes labels for the angles in degrees, ranging from 0 to 360, and a label indicating the location of the "Seed".
Figure 5: InterSource125 Distribution of Radiation Dose
{3}------------------------------------------------
| IBt | November 24, 1998 | Page 19 of 19 |
|--------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Title: | Premarket Notification – InterSource125 | |
| 8.9 | Based on InterSource125 and the predicate device having a similar distribution of<br>radiation dose and using the same radioisotope, InterSource125 is substantially<br>equivalent to the predicate device with respect to radiation dose. | |
| 8.10 | Substantial Equivalence Summary | |
| | 8.10.1 | Based on the similar characteristics for indications, physical size,<br>radiopaque marker, biocompatibility, radioisotope, and radiation dose<br>between the subject device, InterSource125, and the predicate device,<br>InterSource125 is substantially equivalent to the predicate device. |
:
:
{4}------------------------------------------------
Image /page/4/Picture/0 description: The image shows the text "DEPARTMENT OF HEALTH & HUMAN SERVICES" in a bold, sans-serif font. The text is arranged on a single line and is likely part of a document header or title. The words are all capitalized, and the ampersand symbol (&) is used to connect "HEALTH" and "HUMAN".
Public Health Service
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
d 1999 JUN
Ruth Feicht President International Brachytherapy, Inc. 6000 Live Oak Parkway, Suite 107 Norcross, GA 30093
Re:
K984235 InterSource125 Radionuclide Brachytherapy Source Dated: March 10, 1999 Received: March 12, 1999 Regulatory class: II 21 CFR 892.5730/Procode: 90 KXK
Dear Ms. Feicht:
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). 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,
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
{5}------------------------------------------------
510(k) Number (if Known): K984235
Device Name:____InterSource125
Indications For Use:
InterSource125 implants are indicated for interstitial implantation of select localized tumors with low to moderate radiosensitivity. They are used either as primary treatment for tumors such as those of the head, lung, neck, pancreas, prostate, and unresectable tumors, or for residual disease InterSource125 implants are after excision of the primary tumor. indicated for use concurrent with or at the completion of other treatment modalities, such as external beam radiation therapy.
(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Colui k Pollard
Abdominal, ENT
Prescription Use (Per 21 CFR 801.109)
OR
Over-The-Counter-Use
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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.
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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.
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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.
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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.
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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.
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A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
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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.