Advanced Nuclide Technologies LLC (ANT) Model 1 Brachytherapy Sources, with individual activities up to 5 mCi (185 MBq), are indicated for temporary or permanent interstitial, intracavitary, intraluminal or intraoperative implantation or surface application to treat selected localized tumors. They can be used either as primary treatment for unresectable tumors, or as treatment for residual disease after excision of primary or recurrent tumors such as for lung cancer. ANT Model 1 Brachytherapy Source may be used concurrently with or following treatment with other interventions, such as external beam therapy, or chemotherapy. Tumors of the head, neck, lung, pancreas, prostate, breast and other accessible tumors are commonly treated.

Device Description

ANT Model 1 is a singly-encapsulated Brachytherapy Source. It consists of a titanium capsule containing a solid radioactive material. There are two versions of the ANT Model 1. The ANT Model 1 Type-Y contains a solid 169Ytterbium pellet. The ANT Model 1 Type-I contains a solid nonradioactive Ytterbium pellet onto which is plated radioactive 125Iodine. In both cases, the capsule which contains the pellet consists of a deep-drawn titanium can which is closed on the end with a titanium plug which is laser-welded to the can. The ANT Model 1 Brachytherapy Source emits gamma rays and characteristic x-rays from the decay of the respective radionuclides.

AI/ML Overview

This document is a 510(k) premarket notification for the ANT Model 1 Brachytherapy Source. The device appears to be a medical device, and the information provided is primarily focused on demonstrating substantial equivalence to predicate devices, rather than establishing acceptance criteria and performance against those criteria in a typical clinical study format for a diagnostic or AI-driven device.

Based on the provided text, here's an analysis of the "acceptance criteria" and "study" as they pertain to this type of medical device submission:

It's important to note that for a brachytherapy source, "acceptance criteria" often relate to safety, effective radiation delivery, and technical specifications, rather than diagnostic performance metrics like sensitivity or specificity. Moreover, the "study" is primarily non-clinical testing and dosimetric analysis rather than a human-reader clinical trial.

1. A table of acceptance criteria and the reported device performance

For this type of device, the "acceptance criteria" are generally derived from recognized standards and the performance of predicate devices. The "reported device performance" demonstrates that the new device meets or is equivalent to these standards and predicate performance.

Acceptance Criterion	ANT Model 1 Reported Performance	Predicate Device Performance (SPEC M-31, I-Plant 3500)
Design	Singly-encapsulated Titanium capsule (0.85 mm dia x 4.5 mm long) containing a solid Ytterbium rod (0.5 mm dia x 3.0 mm long) for Type-Y, or a solid nonradioactive Ytterbium pellet plated with 125Iodine for Type-I. Capsule is seal welded.	SPEC M-31: Singly-encapsulated Titanium capsule (0.42 mm dia x 5.1 mm long) containing a solid 169Ytterbium rod (0.25 mm dia x 1.25 mm long). Capsule is seal welded.I-Plant 3500: Laser-welded titanium capsule containing a silica tube (substrate for 125Iodine) around a silver radiopaque x-ray marker.
Material (Encapsulation)	Titanium (Medical Grade)	Titanium (Medical Grade) for both predicates.
Radionuclide	169Ytterbium OR 125Iodine	169Ytterbium (SPEC M-31), 125Iodine (I-Plant 3500)
Dosimetry (TG43)	Dose Rate Const (λ):(169Yb): 1.20 cGy h-1 U-1(125I): 1.00 cGy h-1 U-1Anisotropy (φav):(169Yb): 0.95(125I): 0.93Radial Dose Fn: Shown in Figure 1 (not provided in text)	SPEC M-31:Dose Rate Const (λ): 1.24 cGy h-1 U-1Anisotropy (φav): 0.99Radial Dose Fn: Shown in Figure 11 (not provided in text)I-Plant 3500:Dose Rate Const (λ): 1.01 cGy h-1 U-1Anisotropy (φav): 0.95Radial Dose Fn: Shown in Figure 12 (not provided in text)
Sterility	Non-sterile when shipped; sterilized by the user.	Non-sterile when shipped; sterilized by the user for both predicates.
Biocompatibility	Outer encapsulation of medical grade titanium, determined to be biocompatible.	Outer encapsulation of medical grade titanium, determined to be biocompatible for both predicates.
Mechanical Safety	ANSI N43.6 Class C54212 (Prototype sources equaled or exceeded requirements for C53211)	ANSI N43.6 Class C54212 (SPEC M-31), ANSI N43.6 Class C54213 (I-Plant 3500)
Energy Delivered	169Ytterbium: Principal photon emissions 50, 51, 63, 94, 110, 118, 131, 177, 198, 261 and 308 keV gammas.125Iodine: Principal photon emissions 27.4 and 31.4 keV x-rays and a 35.5 keV gamma. Also 22.1 and 25.2 keV fluorescent x-rays.	169Ytterbium (SPEC M-31): Principal photon emissions 50, 51, 57 and 59 keV x-rays and 198, 261 and 308 keV gammas.125Iodine (I-Plant 3500): Principal photon emissions 27.4 and 31.4 keV x-rays and a 35.5 keV gamma. Also fluorescent x-rays from silver marker.
Standards Met	ANSI N43.6, AAPM TG-43	ANSI N43.6, AAPM TG-43 for both predicates.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

Sample Size: This device is a brachytherapy source, not a diagnostic imaging or AI device that uses patient data for a "test set" in the conventional sense. The "test set" here refers to the number of prototype sources subjected to physical and dosimetric testing. The text states "Prototype sources were subjected to the tests..." but does not specify an exact number. It implies a limited number necessary to demonstrate conformity with standards.
Data Provenance: The testing was non-clinical. The standards referenced (ANSI, ISO, AAPM, ESTRO) are international/US standards. The Monte Carlo simulation data would be generated computationally. Therefore, no country of origin or retrospective/prospective data type applies in the context of human patient data.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

This question is not applicable to the type of device and submission. "Ground truth" for this device refers to established physical and dosimetry principles and compliance with recognized standards. This is assessed by specialists in medical physics, radiation safety, and material science, whose expertise is inherent in the development and validation of such standards and the performance of these non-clinical tests. The text cites several peer-reviewed articles by medical physicists (Currier et al., Duggan et al., Perez-Calatayud et al.) which form the basis for the dosimetric analysis.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

This question is not applicable. Adjudication methods like 2+1 (two readers agree, a third acts as tie-breaker) are used in clinical trials involving human interpretation of medical images. For physical and dosimetric testing of a medical device, compliance with standards is typically definitively measured or calculated, not adjudicated by multiple human readers.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

This question is not applicable. An MRMC study is designed for evaluating diagnostic devices, especially those that involve human interpretation and AI assistance. This submission describes a brachytherapy source, which delivers radiation for treatment, not a diagnostic device.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

This question is not applicable. "Standalone performance" in the context of an algorithm refers to its diagnostic accuracy without human intervention. The ANT Model 1 is a physical brachytherapy source; its "performance" is its ability to safely and effectively deliver radiation as determined by physical and dosimetric properties, not an algorithmic output.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)

The "ground truth" for this device's performance is based on established physical laws, validated dosimetric models (Monte Carlo simulation), and internationally recognized engineering and safety standards (ANSI N43.6, ISO 2919, AAPM TG-43). It is not derived from clinical expert consensus, pathology, or outcomes data in the traditional sense, as this device's primary function is physical radiation delivery, not diagnosis.

8. The sample size for the training set

This question is not applicable. "Training set" refers to data used to train machine learning models. The development and validation of a brachytherapy source do not involve machine learning in this context. The underlying physical and dosimetric models are based on fundamental physics and vast amounts of accumulated scientific data and research, not a specific "training set" of patient data for an algorithm.

9. How the ground truth for the training set was established

This question is not applicable, as there is no "training set" for a machine learning model. The underlying scientific principles and validated models used in the design and dosimetric analysis are established through decades of physics research, experimental validation, and peer review in the field of medical physics.

Summary

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Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

November 12, 2014

Advanced Nuclide Technologies, LLC % Sergey Baklanov, Ph.D. President 21756 Green Stable Sgare. #309 ASHBURN VA 20147

Re: K141038 Trade/Device Name: ANT Model 1 Regulation Number: 21 CFR 892.5730 Regulation Name: Radionuclide brachytherapy source Regulatory Class: II Product Code: KXK Dated: November 3, 2014 Received: November 6, 2014

Dear Dr. Baklanov:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and 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) that do not require approval of a premarket approval application (PMA). 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21. Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638 2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours.

Michael D'Hara
for

Janine M. Morris Director Division of Radiological Health Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K141038

Device Name

Advanced Nuclide Technologies LLC (ANT) Model 1 Brachytherapy Source

Indications for Use (Describe)

Type of Use (Select one or both, as applicable)
☑ Prescription Use (Part 21 CFR 801 Subpart D)	☐ Over-The-Counter Use (21 CFR 801 Subpart C)

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P 510(k) Summary

Section 807.92(a)

Advanced Nuclide Technologies, LLC21756, Green Stable Sq., #309Ashburn, VA 20147		267.253.2271
Establishment Registration No.:		To Be Applied For
Contact Person:	Sergey Baklanov, Ph. D., Presidente-mail: Sergey_RMC@msn.com
Date Prepared:	18 June 2014

Device Name: (2)

Classification Name:	Radionuclide Brachytherapy Source (892.5730) (90 KXK)
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Common or Usual Name:	Brachythe
-----------------------	-----------

Proprietary Name: ANT Model 1

(3) Legally Marketed Predicate Devices:
Implant Sciences Corp. I-Plant Model 3500 (1251odine Brachytherapy Seed) cleared under 510(k) number K994317 dated 21 March 2000

and

Source Production & Equipment Co., Inc. Model M-31, cleared under 510(k) number K090366 dated 22 April 2009

(4) Description of ANT Model 1 Brachytherapy Source:
ANT Model 1 is a singly-encapsulated Brachytherapy Source. It consists of a titanium capsule containing a solid radioactive material. There are two versions of the ANT Model 1. The ANT Model 1 Type-Y contains a solid 199Ytterbium pellet. The ANT Model 1 Type-I contains a solid nonradioactive Ytterbium pellet onto which is plated radioactive 1251odine. In both cases, the capsule which contains the pellet consists of a deep-drawn titanium can which is closed on the end with a titanium plug which is laser-welded to the can.

The ANT Model 1 Brachytherapy Source emits gamma rays and characteristic x-rays from the decay of the respective radionuclides.

(5) Intended Use
The intended use of ANT Model 1 Brachytherapy Source is for the treatment of cancer by temporary or permanent interstitial, intracavitary, intraluminal or intraoperative implantation or surface application.

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(6) Technological Characteristics:

The ANT Model 1 Brachytherapy Source is similar to the predicate low dose rate
brachytherapy source and utilizes photons from either 16°Ytterbium or 1251odine.

TechnologicalCharacteristic	Advanced NuclideTechnologies, LLC (ANT)Model 1 BrachytherapySource	Source Production &Equipment Co., Inc. (SPEC)M-31 169YtterbiumBrachytherapy SourceK090366	Implant Sciences Corp.I-Plant Model 3500 (125IodineBrachytherapy Seed)K994317
Design	The source consists of a solidYtterbium rod (0.5 mm dia x3.0 mm long) singlyencapsulated. The capsule(0.85 mm dia x 4.5 mm long)is titanium. The capsule isseal welded.	The source consists of a solid169Ytterbium rod (0.25 mm diax 1.25 mm long) singlyencapsulated. The capsule(0.42 mm dia x 5.1 mm long)is titanium. The capsule isseal welded.	I-Plant Model 3500 (125IodineBrachytherapy Seed) consistsof a laser-welded titaniumcapsule containing a silicatube that serves as asubstrate for the radioactive125Iodine source. The tube ispositioned around a silverradiopaque x-ray marker thatidentifies the source locationand orientation. The seedsare provided non-sterile.
MaterialsRadionuclideEncapsulation	169Ytterbium OR 125IodineTitanium (Medical Grade)	169YtterbiumTitanium (Medical Grade)	125IodineTitanium (Medical Grade)
PerformanceDosimetry (TG43)Dose Rate Const (λ)Anisotropy (φav):Radial Dose Fn:	(169Yb): 1.20 cGy h-1 U-1(125I): 1.00 cGy h-1 U-1(169Yb): 0.95(125I): 0.93Shown in Figure 1	1.24 cGy h-1 U-10.99Shown in Figure 11	1.01 cGy h-1 U-10.95Shown in Figure 12
Sterility	Sources are non-sterile whenshipped. Sources aresterilized by the user.	Sources are non-sterile whenshipped. Sources aresterilized by the user.	Seeds are non-sterile whenshipped. Seeds are sterilizedby the user.
Biocompatibility	The outer encapsulation of theANT Model 1 BrachytherapySource is medical gradetitanium, which has beendetermined to bebiocompatible in a largenumber of medical devices.	The outer encapsulation of theSPEC M31 169YtterbiumBrachytherapy Source ismedical grade titanium, whichhas been determined to bebiocompatible in a largenumber of medical devices.	The outer encapsulation of theI-Plant Model 3500 (125IodineBrachytherapy Seed) ismedical grade titanium, whichhas been determined to bebiocompatible in a largenumber of medical devices.
Mechanical Safety	ANSI N43.6 Class C54212	ANSI N43.6 Class C54212	ANSI N43.6 Class C54213
Energy Delivered	For the ANT Model 1 Type-Y:169Ytterbium (half-life: 32.02days) which decays byelectron capture with theemission of characteristicphotons and electrons. Theelectrons are absorbed by thetitanium wall of the sourceencapsulation. The principalphoton emissions are 50, 51,	169Ytterbium (half-life: 32.02days) which decays byelectron capture with theemission of characteristicphotons and electrons. Theelectrons are absorbed by thetitanium wall of the sourceencapsulation. The principalphoton emissions are 50, 51,57 and 59 keV x-rays and a	125Iodine (half-life: 59.43 days)which decays by electroncapture with the emission ofcharacteristic photons andelectrons. The electrons areabsorbed by the titanium wallof the seed. The principalphoton emissions are 27.4and 31.4 keV x-rays and a35.5 keV gamma. Also
	63, 94, 110, 118, 131, 177,198, 261 and 308 keVgammas.For the ANT Model 1 Type-I:125Iodine (half-life: 59.43 days)which decays by electroncapture with the emission ofcharacteristic photons andelectrons. The electrons areabsorbed by the titanium wallof the source. The principalphoton emissions are 27.4and 31.4 keV x-rays and a35.5 keV gamma. Alsoemitted are 22.1 and 25.2 keVfluorescent x-rays from thesilver substrate.	198, 261 and 308 keVgammas.	fluorescent x-rays from thesilver marker.
Compatibility withEnvironment andOther Devices	169Ytterbium and 125Iodine areradioactive materials andshould be strictly controlled. Ifany source cannot beaccounted for, the loss shouldbe reported to the federal orstate licensing agency.The source should only beused following the conditionsand limitations specified bythe licensing authority (NRCor Agreement State).The source should be storedin a shielded container, eitherthe transport container inwhich it is delivered or othersuitable container.Store at normal roomtemperature.When disposal is indicated,radioactive material should betransferred to an authorizedrecipient, typically the sourcesupplier. Radioactive materialshould never be disposed of innormal waste.	169Ytterbium is a radioactivematerial and should be strictlycontrolled.The source should only beused following the conditionsand limitations specified bythe licensing authority (NRCor Agreement State).The source should be storedin a shielded container, eitherthe transport container inwhich it is delivered or othersuitable container.If any source cannot beaccounted for, the loss shouldbe reported to the federal orstate licensing agency.Store at normal roomtemperature.When disposal is indicated,radioactive material should betransferred to an authorizedrecipient, typically the sourcesupplier. Radioactive materialshould never be disposed of innormal waste.	125Iodine is a radioactivematerial and should be strictlycontrolled. If any significantmaterial cannot be accountedfor, the loss should bereported to the federal or statelicensing agency.When disposal is indicated,radioactive material should betransferred to an authorizedradioactive waste disposalagency. Radioactive materialshould never be disposed of innormal waste.
Where Used	ANT Model 1 BrachytherapySource is designed to beopened and used in theoperating room.	SPEC Model M31Brachytherapy Source isdesigned to be opened andused in the operating room.	I-Plant Model 3500 (125IodineBrachytherapy Seed) isdesigned to be opened andused in the operating room.
Standards MetMechanicalDosimetry	ANSI N43.6AAPM TG-43	ANSI N43.6AAPM TG-43	ANSI N43.6AAPM TG-43
Electrical Safety	Not Applicable	Not Applicable	Not Applicable
Thermal Safety	Not Applicable	Not Applicable	Not Applicable
Radiation Safety	These 169Ytterbium and125Iodine sources areradioactive, and appropriateprecautions must be takenduring handling to minimizeradiation exposure topersonnel. Personnelmonitoring is required.This sources should behandled with as muchdistance as practical betweensources and the operator.Any manipulation of ANTModel 1 sources should becarried out behind shielding ofadequate thickness.The first half value thicknessof lead for 169Ytterbium is 0.25mm. A 6.7 mm lead sheet willprovide >99% reduction inexposure.The half value thickness oflead for 125Iodine is 0.025 mm.Thus, a 0.25 mm lead sheetwill provide >99% reduction inexposure.	This 169Ytterbium source isradioactive, and appropriateprecautions must be takenduring handling to minimizeradiation exposure topersonnel. Personnelmonitoring is required.This source should behandled with as muchdistance as practical betweensources and the operator.Any manipulation of SPECModel M31 sources should becarried out behind shielding ofadequate thickness. The firsthalf value thickness of lead for169Ytterbium is 0.25 mm. A 6.7mm lead sheet will provide>99% reduction in exposure.	I-Plant Model 3500 (125IodineBrachytherapy Seed) isradioactive, and appropriateprecautions must be takenduring handling to minimizeradiation exposure topersonnel. Personnelmonitoring is required.I-Plant Model 3500 (125IodineBrachytherapy Seed) shouldbe handled with forceps onlyand with as much distance aspractical between seeds andthe operator.Any manipulation of I-PlantModel 3500 (125IodineBrachytherapy Seed) shouldbe carried out behindshielding of adequatethickness. The half valuethickness of lead for 125Iodineis 0.025 mm. Thus, a 0.25 mmlead sheet will provide >99%reduction in exposure.

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Section 807.92(b)

Nonclinical Tests (1)

Physical Testing

The ANT Model 1 source has been subjected to the tests specified in American National Standard (ANSI) N43.6 and International Organization for Standardization (ISO) Standard 2919, as referenced in the FDA "Guidance for the Submission of Premarket Notifications for Photon-Emitting Brachytherapy Sources" dated 2 August 2000.

Prototype sources were subjected to the tests specified in ANSI N43.6-2007 and ISO 2919-2012 and have equaled or exceeded the requirements corresponding to a classification of C53211, which is the requirement for brachytherapy sources. This is equivalent to the physical testing of the predicate devices.

Dosimetry

The dose distribution around the ANT Model 1 source was calculated by Monte Carlo simulation in accordance with the recommendations of the American Association of Physicists in Medicine and the European Society for Therapeutic Radiation Oncology. 3 This is equivalent to the dosimetry of the predicate devices.

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(2) Clinical Tests
Not Applicable
(3) Conclusions
The results of the nonclinical physical tests and the dosimetric analysis, demonstrate that the ANT Model 1 Brachytherapy Source is as safe, as effective, and performs as well or better than the legally marketed predicate devices:

Implant Sciences Corp. I-Plant Model 3500 (128)odine Brachytherapy Seed) cleared under 510(k) number K994317 dated 21 March 2000

and

Source Production & Equipment Co., Inc. Model M-31, cleared under 510(k) number K090366 dated 22 April 2009

1 Currier B, Munro JJ and Medich DC, Dosimetric characterization of the GammaClip™ 169Yb low dose rate permanent implant brachytherapy source for the treatment of nonsmall cell lung cancer postwedge resection. Med Phys. 2013 Aug:40(8):080701

2 Duggan DM, Johnson BL, "Dosimetry of the I-Plant Model 3500 iodine-125 brachytherapy source", Med Phys 2001 Apr;28(4):661-70

3 Perez-Calatayud J. Ballester F. Das RK, Dewerd LA, Ibbott GS, Meigooni AS, Quhib Z, Rivard MJ, Sloboda RS, Williamson JF, Dose calculation for photon-emitting brachytherapy sources with average energy higher than 50 keV: report of the AAPM and ESTRO, Med Phys. 2012 May;39(5):2904-29

Regulation Number and Section

§ 892.5730 Radionuclide brachytherapy source.

(a)
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.(b)
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.