CENTRAL AXIS MARKER

Description of Event or Problem

THERAPIST INTERRUPTED AFTER INITIAL SETUP AND THE DEVICE (CENTRAL AXIS MARKER) WAS LEFT IN THE WEDGE MOUNT ASSEMBLY. WHEN TREATING THERE WAS NO ACCESSORY INTERLOCK CODED ON DEVICE (CENTRAL AXIS MARKER) IN THE LINAC. TREATED PATIENT WITH THE DEVICE (CENTRAL AXIS MARKER) STILL IN PLACE. MEASUREMENTS OF THE ATTENUATION OF THE POLYCARBONATE MATERIAL OF THE DEVICE (CENTRAL AXIS MARKER) SHOWED AN UNDERDOSE OF 5% IN THE TREATMENT VOLUME BEYOND THE 5X5CM. NO CORRECTION FOR UNDERDOSE WAS REQUIRED/ REPORTED.

Additional Manufacturer Narrative

METHOD: DEVICE WAS NOT AVAILABLE FOR EVALUATION. THE CUSTOMER AND CIVCO MEDICAL ENGINEER REVIEWED THE SITUATION VIA PHONE. DEVICE IS DELIVERED TO CUSTOMER UNCODED, MEANING THAT THE LINAC DOSE NOT KNOW IT IS IN PLACE WHEN IT IS INSERTED INTO THE HEAD/WEDGE MOUNT ASSEMBLY. MANUFACTURER RECOMMENDS THAT THEY SHOULD CODE IT (FILL IN THE APPROPRIATE HOLES TO MATCH THEIR BB TRAY). THIS WAY THE SYSTEM WILL LET THEM IMAGE WITH IT IN, BUT NOT TREAT - IT WILL CAUSE AN INTERLOCK AND PREVENT THEM FROM TREATING UNTIL THEY PULL THE TRAY. CONCLUSION: USER ERROR CAUSED EVENT AS DEVICE WAS NOT REMOVED PRIOR TO TREATMENT. DEVICE WAS NOT CODED PRIOR TO USE WHICH PREVENTS TREATING WITH THE TRAY IN PLACE AND THIS CONTRIBUTED TO THE EVENT.