510(k) · Cleared

Cleared

North American Scientific (Nasi) I-125 Radionuclide Brachytherapy Source- Model Med 3631-a

K972271510(k) TraditionalCleared Oct 28, 1997132-day reviewClass II21 CFR 892.5730

Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly, last Nov 3, 2026

Ml Strategies, Inc. · KXK Source, Brachytherapy, Radionuclide

Cleared on Oct 28, 1997 after a 132-day review. FDA’s file for it is a 510(k) statement, which names no predicate. 29 later devices descend from it.

Decided: Oct 28, 1997
Review: 132 days
Class: Class II
Product code: KXK
Recalls: None
Predicates: 0

29 later devices descend from it, 5 citing it directly.

This deviceK972271 North American Scientific (Nasi) I-125 Radionuclide Brachytherapy…Ml Strategies, Inc. · 1997
Descendant · cites it directly · 20 of its ownK982226 Uromed Brachytheraphy Iodine-125 SourcesUromed Corp. · 1999
Descendant · 2 generations on · 18 of its ownK021343 Isoseeds I-125Bebig Isotopen-Und Medizintechnik GmbH · 2002
Descendant · 2 generations on · 14 of its ownK040339 Brachytherapy Strand DeviceBebig Isotopen-Und Medizintechnik GmbH · 2004
Descendant · 3 generations on · 9 of its ownK043596 Theraload Custom Loaded Needles, Models 200 and 125.S06Theragenics Corp. · 2005
Descendant · 3 generations on · 7 of its ownK062384 Cesium-131 Strand, Strand Preload, Preload, S-CartridgeIsoray, Inc. · 2006

Showing 5 of 29 descendants. See all descendants

Descendants cleared per year

1998high 4 (1999) · low 0 (2001)2026

Most influential descendants

Showing 5 of 29 · See all

K982226Uromed Brachytheraphy Iodine-125 SourcesUromed Corp. · 1999 · cites it directly20descendants
K021343Isoseeds I-125Bebig Isotopen-Und Medizintechnik GmbH · 2002 · 2 generations on18descendants
K040339Brachytherapy Strand DeviceBebig Isotopen-Und Medizintechnik GmbH · 2004 · 2 generations on14descendants
K043596Theraload Custom Loaded Needles, Models 200 and 125.S06Theragenics Corp. · 2005 · 3 generations on9descendants
K062384Cesium-131 Strand, Strand Preload, Preload, S-CartridgeIsoray, Inc. · 2006 · 3 generations on7descendants

View FIG. 1 as a table

Line of descent and top descendants

Generation	Number	Device	Applicant	Decided	Recalls
0 (this device)	K972271	North American Scientific (Nasi) I-125 Radionuclide Brachytherapy Source-…	Ml Strategies, Inc.	1997	—
+1	K982226	Uromed Brachytheraphy Iodine-125 Sources	Uromed Corp.	1999	—
+2	K021343	Isoseeds I-125	Bebig Isotopen-Und Medizintechnik GmbH	2002	—
+2	K040339	Brachytherapy Strand Device	Bebig Isotopen-Und Medizintechnik GmbH	2004	—
+3	K043596	Theraload Custom Loaded Needles, Models 200 and 125.S06	Theragenics Corp.	2005	—
+3	K062384	Cesium-131 Strand, Strand Preload, Preload, S-Cartridge	Isoray, Inc.	2006	—

Descendants by year cleared

Year cleared	Devices	With a Class I recall
1998	1	0
1999	4	0
2000	2	0
2002	2	0
2003	1	0
2004	1	0
2005	1	0
2006	2	0
2007	1	0
2009	4	0
2011	1	0
2012	1	0
2014	2	0
2018	1	0
2019	1	0
2020	2	0
2022	1	0
2025	1	0

FIG. 1 — Lineage of K972271, 1997–2025Source: FDA 510(k) summaries, read by 510(k) Report · How lineage is built

Sources: FDA 510(k) database (decision fields), the FDA 510(k) statement (indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.

Planning a device in KXK? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.

Top candidate predicates for a new KXK device

#1 K242818 IsoSpherescore 10.9 · 5 generations · no Class I recall
#2 Held for the reportin the report
#3 Held for the reportin the report

Get a 510(k) Report

What was it cleared against?

FDA’s file for it is a 510(k) statement, which names no predicate.

What descends from it? (29)

See all 29

5 later devices cite it directly; ranked here by how many devices descend from each in turn.

Number	Device	Applicant	Decided	Descendants
K982226	Uromed Brachytheraphy Iodine-125 Sources	Uromed Corp.	1999	20
K982421	Imagyn 125 I Seed, Model IS 125	International Isotopes, Inc.	1998	6
K990193	Iodine Brachytherapy Seeds, Model 3000	Implant Sciences Corp.	1999	4
K992963	I3RAD 125 I Brachytherapy Seed, Model I125-0401	International Isotopes, Inc.	1999	0
K991526	Isostar I-125 Interstitial Seed, Model IS-12501	Imagyn Medical Technologies, Inc.	1999	0

Has anything in its family been recalled? (0 Class I)

No FDA recall names this device.

No ancestor or descendant has a Class I recall.

What does this lineage say?

Of its descendants, K982226 (Uromed Corp., 1999) has gone furthest, with 20 descendants of its own.

How does its category compare?

All KXK devices

KXK Source, Brachytherapy, Radionuclide: FDA decisions, review times, recalls and adverse event reports over 20 years.

FDA decisions per year · KXK

2in 2025

2007high 8 (2014) · low 0 (2021)2026

2026 to Oct 25, outlined.

Median 510(k) review, days · KXK

158in 2020

2007high 158 (2020) · low 42 (2007)2026

Receipt to decision; years with fewer than 3 clearances left blank.

Recalls per year · KXK

1in 2016

2007high 1 (2008) · low 0 (2007)2026

Class I (0 since 2007) Class II/III not classified

Adverse event reports per year · KXK

7in 2025

2007high 62 (2021) · low 0 (2010)2025

MAUDE reports naming product code KXK, not matched to any one device; reports are not rates.

View these four charts as a table

Year	Decisions	Median 510(k) review, days	Recalls (Class I)	MAUDE reports
2007	5	42	0	9
2008	1	—	1	15
2009	7	63	0	10
2010	1	—	0	0
2011	5	94	1	35
2012	3	109	1	4
2013	3	127	0	29
2014	8	96	0	13
2015	2	—	0	6
2016	4	49	1	40
2017	2	—	0	41
2018	1	—	0	28
2019	2	—	0	10
2020	3	158	0	15
2021	0	—	0	62
2022	1	—	0	26
2023	1	—	0	9
2024	0	—	0	15
2025	2	—	0	7
2026	0	—	0	—

What is it indicated for?

The North American Scientific Corporation’s I-125 Radionuclide Brachytherapy Source Model MED3631-A is a device intended to deliver radiation by interstitial intracavity or surface application for therapy of malignant lesions.

Indications for use read by OCR from a scanned FDA 510(k) statement, so letters may be misread. Check the PDF before quoting it.

https://510kreport.com/device/K972271 · printed Nov 4, 2026

Cite this page

510(k) Report. “K972271: North American Scientific (Nasi) I-125 Radionuclide Brachytherapy Source- Model Med 3631-a.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 4, 2026. https://510kreport.com/device/K972271

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Record history

FDA decision record loaded May 2, 2026
Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
Lineage and recalls computed Nov 3, 2026
Page last updated Nov 3, 2026