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Status of NRC Permanent Implant Brachytherapy Medical Event Definition: An Update. Michael Fuller Team Leader Medical Radiation Safety Team U.S. NRC. Purpose.
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Status of NRC Permanent Implant Brachytherapy Medical Event Definition: An Update Michael Fuller Team Leader Medical Radiation Safety Team U.S. NRC
Purpose • To provide an overview and an update of the proposed changes to the Medical Event definition (criteria) as it relates to Permanent Implant Brachytherapy. 2
Changes to Medical Event Definition • In August 2010, The Commission Directed NRC Staff to: • Work closely with the Advisory Committee for the Medical Uses of Isotopes (ACMUI), the Agreement States, and the medical community to develop medical event (ME) definitions that would: • Protect the interests of patients, • Allow physicians the flexibility to take actions that they deem medically necessary, • Preserve the NRC’s ability to detect misapplications of radioactive material and failures in process, procedure and training. 3
Workshops • ACMUI Meeting in Rockville, April 2011 • First Workshop in New York, June 2011 • Second Workshop in Houston, August 2011 4
Key Messages Received During the Workshops • Among the Agreement States - fairly consistent with NRC regulations, but wide variance in the interpretation and implementation of the regulations. • ME definition for permanent implant brachytherapy needs to be revised, and should be based upon total source strength (activity) not absorbed dose. 5
Key Messages Received During the Workshops • If ME definition is based upon total source strength, a tolerance of + 20% is reasonable. • The term “Medical Event” should be reserved for those instances where there is real harm to the patient or a potential for same (clinically significant). 6
Key Messages Received During the Workshops • Licensee staff should be trained in the policies and procedures for identifying MEs. • Patient’s rights should be protected. • Authorized Users should be required to attest in writing, that the distribution of seeds, within the target was implanted as intended. • Post-implant imaging should be required. 7
Recent Developments • In February 2012, the ACMUI held a public teleconference and provided NRC staff with recommendations for changes to the ME definition for permanent implant brachytherapy. • In April 2012, NRC staff provided the Commission with the staff’s recommendations for changes to the ME definition for permanent implant brachytherapy. 8
NRC Staff’s Recommendations • Define separate ME criteria for permanent implant brachytherapy utilizing radioactive sources. • For treatment site, a ME occurs when 20% or more of implanted sources are outside the intended implant location. 9
NRC Staff’s Recommendations • For normal tissue in neighboring structures, a ME occurs when the dose to at least 5 contiguous cc exceeds 150% of the dose prescribed for the treatment site. • For normal tissue structures within treatment site, a ME occurs when the dose to at least 5 contiguous cc exceeds 150% of the expected dose for that tissue. 10
NRC Staff’s Recommendations • A ME occurs when the treatment is administered: • using wrong radionuclide; or • using wrong source strength (+/- 20%) as specified in the written directive; or • to the wrong patient; or • with implantation directly into the wrong site or body part; or • with delivery using the wrong modality; or • using leaking sources. 11
NRC Staff’s Position • All of the recommended ME criteria reflect circumstances in which there is actual or potential harm to patients being treated. • Patient interests will be protected. • Physicians will be able to take medically necessary actions. 12
NRC Staff’s Position • NRC will be able to continue detecting failures in process, procedures, and training plus misapplications by Authorized Users. • Key Stakeholder input is reflected in these recommendations. 13
WHAT’S NEXT? • On August 13, 2012 The Commission Approved the NRC Staff’s Recommendations for Changes to the ME Definition for Permanent Implant Brachytherapy • Staff Develops a Regulatory Basis for a Proposed Rule • Proposed Rule 14
QUESTIONS? 15