ENS 43008
ENS Event | |
|---|---|
08:00 Nov 16, 2006 | |
| Title | Agreement State - Washington - Gamma Knife Overexposure |
| Event Description | The Washington State Department of Health (DOH) received a preliminary telephone report, November 22, from University of Washington, Harborview Gamma Knife, that a dose of 28 Grays had been administered to a patient. The exposure exceeded the prescribed exposure of 18 Grays by 10 Grays. The cause, thus far, is unknown. DOH is to receive a written report within 15 days.
The dose was administered by a Leksell Gamma System Model 24001 Type C gamma knife with 7,236 Curies of Co-60. The patient or responsible relative has been notified. The licensee is required to notify DOH within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The notification is apparently several days late. Washington State report number: #WA-06-066
The State provided the following update information via email: The cause was stated by the licensee to be human error. The prescribing physician, apparently in a hurry to leave for the day, had prescribed 18 Gy. The physician then entered the Rx value into the computer treatment plan rather than having the medical physicist do it as is the usual procedure. The physician erroneously entered 28 Gy. The licensee stated the tumor undergoing treatment turned out to be larger than expected consequently the 28 Gy administered remains therapeutic with likely no ill-effects expected as a result of this incident. The treatment plan has been modified so that a similar event is less likely to occur. The progress of the patient is being closely watched by the licensee. DOH is expecting receipt of a written report from the licensee this week." Notified the R4DO (Smith) and NMSS EO (Janosko).
The Department has received the licensee's written report of the incident and proposed corrective action. Corrective actions now include a verification process to ensure the correct treatment dose has been transferred from the treatment planning computer to the Gamma Knife computer prior to patient therapy. A plan signed by the treating oncologist, physicist, and neurosurgeon is now required. In addition the treating oncologist and physicist will verify and initial the prescription dose and isodose. Before a patient is treated, the nursing still will confirm: the patient's name/identity; the disease process; the disease site; the prescribed dose; and the prescribed isodose. These actions appear adequate at this time and will be reviewed during the Department's next visit to the facility. The effect to the individual is unknown at this time. However, it is expected that there will be minimal symptoms related to the larger radiation dose. A longer course of steroids than was initially planned may be prescribed. 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. |
| Where | |
|---|---|
| University Of Washington Harborview Gamma Knife Seattle, Washington (NRC Region 4) | |
| License number: | WN-M0219-1 |
| Organization: | Wa Division Of Radiation Protection |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+154.1 h6.421 days <br />0.917 weeks <br />0.211 months <br />) | |
| Opened: | Arden Scroggs 18:06 Nov 22, 2006 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Dec 19, 2006 |
| 43008 - NRC Website | |
University Of Washington Harborview Gamma Knife with Agreement State | |
WEEKMONTHYEARENS 430082006-11-16T08:00:00016 November 2006 08:00:00
[Table view]Agreement State Agreement State - Washington - Gamma Knife Overexposure 2006-11-16T08:00:00 | |