ENS 46422
ENS Event | |
|---|---|
05:00 Nov 13, 2010 | |
| Title | |
| Event Description | The following report was received from the State of North Carolina via email:
This is to notify you about a medical event under the regulation .0364, i.e., within 24-hr notification requirement after discovery. The following summarizes the medical event. Event: Contamination of I-123 thyroid imaging dose with I-131 (WRONG RADIONUCLIDE). Dose: 380 rad (3.8 Gy) to the thyroid gland (EXCEEDS 50-RAD THRESHOLD FOR ORGAN DOSE) Notification: Patient's parent and referring physician have been notified. A detailed report will follow within 15 days. This event occurred sometime on Friday 11/13/10 and was discovered on Monday 11/15/10 at 1535 hrs. The patient was a child and potential adverse effects have not been determined at this time. A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.
DESCRIPTION OF THE EVENT: A patient was administered 0.389 mCi of iodine-123 orally for a thyroid uptake and scan procedure. Upon imaging at 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, the technologist noted excessive background in the image. The acquisition computer showed an additional peak at 364 keV, consistent with presence of iodine-131 contamination. The iodine-131 thyroid burden at 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> was estimated to be about 43 microcuries. Based upon an iodine-123 uptake of 30%, the intake of iodine-131 was estimated to be about 143 microcuries. The absorbed dose to the thyroid, as estimated on 11/15/2010, was about 3.8 Gy (380 rad), or an equivalent dose of 3.8 Sv (380 rem), assuming age-specific reference values for thyroid mass and effective half-life. An intake of 143 mCi of iodine-131 is comparable to activities that were administered in the past for diagnostic thyroid imaging, and no adverse effects are expected. WHY THE EVENT OCCURRED: Interviews with staff and assaying the equipment used for the iodine-123 administration indicate that the screw-cap on the vial was the likely source of the contamination. It is unclear whether the screw-cap removal device, or improper handling of the cap, was the cause of the contamination. STEPS BEING TAKEN TO PREVENT A RECURRENCE: The Authorized User and senior technical staff have educated staff about proper handling of radioiodine. To prevent a recurrence, we have changed our procedure as follows: 1) Only one radioiodine dose will be kept in the 'dosing hood' at any time. 2) The vial will be opened only when the patient and necessary staff are in the hot lab. 3) A separate cap remover will be used for each radionuclide. 4) Only one technologist will be involved with preparing dosing area, dosing the patient, cleaning up the dosing area and surveying post therapy. North Caroline Incident #: NC 10-50 Notified R1DO - R. Conte and FSME - G. Villamar
The I-131 intake is being corrected to 143 microcuries, instead of 143 millicuries, as reported previously. Notified the R1DO (Schmidt) and FSME (Villamar). |
| Where | |
|---|---|
| Duke University And Medical Center Durham, North Carolina (NRC Region 1) | |
| License number: | 032-0247-4 |
| Organization: | Nc Div Of Radiation Protection |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+78.02 h3.251 days <br />0.464 weeks <br />0.107 months <br />) | |
| Opened: | Paul Huggins 11:01 Nov 16, 2010 |
| NRC Officer: | John Shoemaker |
| Last Updated: | Dec 2, 2010 |
| 46422 - NRC Website | |
Duke University And Medical Center with Agreement State | |
WEEKMONTHYEARENS 464222010-11-13T05:00:00013 November 2010 05:00:00
[Table view]Agreement State Agreement State Report - Patient Received a Thyroid Imaging Dose of I-123 That Was Contaminated with I-131 2010-11-13T05:00:00 | |