|AGREEMENT STATE REPORT - UNPLANNED DOSE TO AN ORGAN
The following was received from the state of Wisconsin's Radiation Protection Section [the Department] via email:
"On March 20, 2020, the [Wisconsin Radiation Protection Section] Department was notified by the licensee of a medical event which occurred the same day. The licensee was performing the first fraction of a vaginal cylinder treatment using a Varian VariSource iX high dose rate remote afterloader unit. Licensee staff had difficulty removing the cylinder post-treatment, and they determined that the cylinder had perforated the patient's tissue at some point following pre-treatment imaging. The licensee estimates the cylinder moved 3-4 cm from its original position. Dose reconstruction is ongoing, but is expected to exceed the 0.5 Sv threshold to the bowel. This is all the information available at this time. The Department will determine follow-up actions and provide additional information when available."
* * * UPDATE ON 3/25/20 AT 1612 EDT FROM MEGAN SHOBER TO BETHANY CECERE * * *
"The Department performed an investigation on March 25, 2020 to review this incident. For this fraction, the patient was prescribed a 6 Gy dose to the surface of the vaginal cylinder. Using CT imaging the licensee confirmed the proper placement of the cylinder prior to treatment. The licensee performed all pre-treatment checks, connected the patient to the HDR unit, and initiated treatment. Everything appeared to be as expected. However, following treatment it was very difficult for the authorized user to remove the cylinder; there appeared to be a vacuum suction seal. The licensee determined that the cylinder had been pulled an additional 3.5 cm into the patient, perforating the vaginal wall and protruding into the bowel space. The licensee believes that the bowel conformed to the shape of the cylinder during part or all of treatment, causing a much larger volume of the bowel to receive an elevated radiation dose as compared to the treatment plan. Based on the prescribed dose, the maximum unintended dose to the bowel is 6 Gy. The patient and referring physician were immediately informed of the event. The authorized user does not expect the patient to experience any radiological consequences from this event."
Wisconsin Event Report ID No.: WI200010
Notified R3DO (Hanna) and NMSS Events Notification Email.
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.