Event Notification Report for December 03, 2008
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
12/02/2008 - 12/03/2008
EVENT NUMBERS
45622
General Information or Other
Event Number: 45622
Rep Org: TEXAS DEPARTMENT OF HEALTH
Licensee: PRESBYTERIAN HEALTHCARE SYSTEM
Region: 4
City: DALLAS State: TX
County:
License #: 04288
Agreement: Y
Docket:
NRC Notified By: ART TUCKER
HQ OPS Officer: JOE O'HARA
Licensee: PRESBYTERIAN HEALTHCARE SYSTEM
Region: 4
City: DALLAS State: TX
County:
License #: 04288
Agreement: Y
Docket:
NRC Notified By: ART TUCKER
HQ OPS Officer: JOE O'HARA
Notification Date: 01/11/2010
Notification Time: 15:37 [ET]
Event Date: 12/03/2008
Event Time: 00:00 [CST]
Last Update Date: 01/11/2010
Notification Time: 15:37 [ET]
Event Date: 12/03/2008
Event Time: 00:00 [CST]
Last Update Date: 01/11/2010
Emergency Class: NON EMERGENCY
10 CFR Section:
10 CFR Section:
Person (Organization):
BOB HAGAR (R4DO)
ANGELA MCINTOSH (FSME)
BOB HAGAR (R4DO)
ANGELA MCINTOSH (FSME)
AGREEMENT STATE REPORT - MEDICAL EVENT INVOLVING A GAMMA KNIFE
"On December 2, 2008 Austin Headquarters IIP [Incident Investigation Program], was notified of a medical event with a Leksell Gamma Knife resulting in a dose of approximately 15 Gray (1,500 rad) to the wrong cranial nerve. The incident involved the use of a medical gamma stereotactic radio surgical device known as a gamma knife (GK). Essentially the wrong nerve was designated for treatment for a trigeminal procedure that typically calls for a 80 Gray dose within a 4 mm sphere. Treatment of trigeminal neuralgia can account for as many as 20% of the workload on GK facilities with a standard protocol of 80 Gray to the base of the 5th intracranial nerve yet in this case the 7th cranial nerve was mistakenly targeted. Fortunately, for a reason not clear, the authorized neurosurgeon instructed the Licensed Medical Physicist (LMP) to pause the treatment 9 minutes into a 45 minute regime. He then consulted again with the neuroradiologist on the case and they both determined that the slice used in the treatment plan was the 7th not the intended 5th cranial nerve some one centimeter [away]. The physicians on the case do not expect any untoward effect upon the patient who was notified of the mishap and actually resumed successful treatment on the same day. It was the conclusion of the clinical staff who participated on the case that the root cause was a misidentification of the anatomical target site as listed on the Written Directive (WD). The 15 day report by the RSO stated that he has implemented specific measures as corrective actions to prevent recurrence. These include: 1) a change in the written procedures to include a verification of the target site by the neuroradiologist for each case and 2) a modified WD to document the new procedural change to ensure that the correct treatment site is targeted and treated in each procedure.
"The department will conduct a review of at least 20% of past cases to ensure that this error had not occurred before however the clinicians were of the opinion that such a dose to the wrong site would have pronounced and readily observable clinical manifestations.
"On December 17, 2008 the Agency [State of Texas] received a fax from [the] licensee Radiation Safety Officer detailing the medical event. He noted that the Written Directive was complete and signed by all appropriate parties. The exposure to the 7th cranial never was precisely 9.17 minutes resulting in a dose to other tissue of 14.95Gy and to the 5th trigeminal nerve (targeted site) a negligible dose of 10-20 cGy while 80 Gy was intended. Therefore the patient had treatment continued on the correct anatomical site with apparent success. The authorized physicians attest that the misadministration will have no untoward effects upon the patient. For corrective action it will be documented that the neuroradiologist has provided precise information on the MRI slice of the 5th cranial nerve for Trigeminal Neuralgia treatments.
"This event was reported to the Nuclear Material Events Database (NMED) (090019) instead of to the Headquarters Operations Officer as required. This file is closed in NMED."
Texas Incident No. I-8585
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.
"On December 2, 2008 Austin Headquarters IIP [Incident Investigation Program], was notified of a medical event with a Leksell Gamma Knife resulting in a dose of approximately 15 Gray (1,500 rad) to the wrong cranial nerve. The incident involved the use of a medical gamma stereotactic radio surgical device known as a gamma knife (GK). Essentially the wrong nerve was designated for treatment for a trigeminal procedure that typically calls for a 80 Gray dose within a 4 mm sphere. Treatment of trigeminal neuralgia can account for as many as 20% of the workload on GK facilities with a standard protocol of 80 Gray to the base of the 5th intracranial nerve yet in this case the 7th cranial nerve was mistakenly targeted. Fortunately, for a reason not clear, the authorized neurosurgeon instructed the Licensed Medical Physicist (LMP) to pause the treatment 9 minutes into a 45 minute regime. He then consulted again with the neuroradiologist on the case and they both determined that the slice used in the treatment plan was the 7th not the intended 5th cranial nerve some one centimeter [away]. The physicians on the case do not expect any untoward effect upon the patient who was notified of the mishap and actually resumed successful treatment on the same day. It was the conclusion of the clinical staff who participated on the case that the root cause was a misidentification of the anatomical target site as listed on the Written Directive (WD). The 15 day report by the RSO stated that he has implemented specific measures as corrective actions to prevent recurrence. These include: 1) a change in the written procedures to include a verification of the target site by the neuroradiologist for each case and 2) a modified WD to document the new procedural change to ensure that the correct treatment site is targeted and treated in each procedure.
"The department will conduct a review of at least 20% of past cases to ensure that this error had not occurred before however the clinicians were of the opinion that such a dose to the wrong site would have pronounced and readily observable clinical manifestations.
"On December 17, 2008 the Agency [State of Texas] received a fax from [the] licensee Radiation Safety Officer detailing the medical event. He noted that the Written Directive was complete and signed by all appropriate parties. The exposure to the 7th cranial never was precisely 9.17 minutes resulting in a dose to other tissue of 14.95Gy and to the 5th trigeminal nerve (targeted site) a negligible dose of 10-20 cGy while 80 Gy was intended. Therefore the patient had treatment continued on the correct anatomical site with apparent success. The authorized physicians attest that the misadministration will have no untoward effects upon the patient. For corrective action it will be documented that the neuroradiologist has provided precise information on the MRI slice of the 5th cranial nerve for Trigeminal Neuralgia treatments.
"This event was reported to the Nuclear Material Events Database (NMED) (090019) instead of to the Headquarters Operations Officer as required. This file is closed in NMED."
Texas Incident No. I-8585
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.