ENS Event | |
|---|---|
04:00 May 18, 2022 | |
| Title | Target Tissue Missed |
| Event Description | The following was received from the Pennsylvania Department of Environmental Protection (the Department) via email:
On May 19, 2022, the licensee informed the Department of an incident involving Cobalt 60 in a Leksell (R) Gamma Knife Perfexion. It is reportable as per 10 CFR 35.3045(a)(1). On May 18, 2022, a patient underwent treatment of four lesions in the brain. Upon review of the treatment, the physicist noticed that all four lesions were missed by approximately 0.5 centimeters and healthy brain tissue was treated. The patient and referring physician have been informed. The Department is currently in contact with the licensee and will update this event as soon as more information is provided. The Department will perform a reactive inspection. More information will be provided as received. Event Report ID No: PA220018 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.
The following updated was received from the Department via email: The patient had MRIs and CT Scans. Those images were fused by the neurosurgeon and radiation oncologist. Upon completion of the treatment, they discovered that although the targets were moved with the second image fusion, the shots and contours were not. This resulted in the treatment being 0.5 cm off for all 4 targets. Prescribed dose was 20 to 21 Gy, delivered dose to target tissue was 8 to 15 Gy, maximum dose to healthy tissue is estimated to range from 21.82 to 27.09 Gy. More information is expected once the licensee completes their investigation. Notified R1DO (Eve) and NMSS Events Notification via email. |
| Where | |
|---|---|
| University Of Penn. Philadelphia Philadelphia, Pennsylvania (NRC Region 1) | |
| License number: | PA-0131 |
| Organization: | Pa Dept Of Environmental Protection |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+53.35 h2.223 days <br />0.318 weeks <br />0.0731 months <br />) | |
| Opened: | John Chippo 09:21 May 20, 2022 |
| NRC Officer: | Thomas Herrity |
| Last Updated: | May 25, 2022 |
| 55904 - NRC Website | |
University Of Penn. Philadelphia with Agreement State | |
WEEKMONTHYEARENS 559042022-05-18T04:00:00018 May 2022 04:00:00
[Table view]Agreement State Target Tissue Missed 2022-05-18T04:00:00 | |