MAUDE Adverse Event Report: VARIAN MEDICAL SYSTEMS, INC SURFACE APPLICATOR SET WITH LEIPZIG-STYLE CONE

Model Number GM11010800

Device Problem Labelling, Instructions for Use or Training Problem (1318)

Patient Problem Radiation Overdose (1510)

Event Date 03/26/2015

Event Type  malfunction  

Event Description

Varian has discovered that there is a discrepancy in the absolute dose rate given with the leipzig-style surface applicator's instruction for use (ifu): dose characterization gm11010080 (b)(6) 2012.This issue was discovered by a customer during commissioning of the leipzig-style surface applicators using thermo luminescent dosimeters (tld).The customer found 24% discrepancy in their tld-measured dose as compared to the varian ifu.The most significant discrepancy is that the actual dose rate of the applicator is approximately 14% higher than the rate published within the ifu.Use of the dose rate within the ifu without independent confirmation of the dose could result in an adminstration of the dose greater than intended.The patient's treatment was prescribed for 400cgy per fraction x 8 fractions, to a depth of 3mm.The dose rate used to plan the treatment dwell time was the dose rate given in the ifu of 21.5 cgy/min/ci (at 5mm).This would result in an overdose of 14% (456cgy per fraction).The site is anticipating making dosimetric adjustments to the final fractions.Per varian's medical professional assessment, the pt has most likely been unharmed by the overdose and would not experience a serious injury as the overdose from the 3 fractions treated results in a low risk for skin/tissue necrosis and could be further mitigated by reducing the daily fraction dose.

Manufacturer Narrative

The issue was investigated by varian.A review of the following was carried out: the applicator ifu, data given to varian from (b)(4) as part of the (b)(4) ((b)(4) was contracted to perform characterizations of the applicators to provide data for the ifu), (b)(4) ref guide, the tld data from the clinical site, as well as a report generated by (b)(4) in 2013.The discrepancy between the dose rate published in the applicator's ifu and the dose rate from corrected (b)(4), and physical measurement was verified.The root cause was validation and verification error; a failure for (b)(4) and varian to come together and review all deliverables together at the end of the characterization project.The ifu will be updated with corrected dose rates.(b)(4).

• Brand Name: SURFACE APPLICATOR SET WITH LEIPZIG-STYLE CONE
• Type of Device: SURFACE APPLICATOR
• Manufacturer (Section D): VARIAN MEDICAL SYSTEMS, INC; 3100 hansen way; palo alto CA 94304
• Manufacturer (Section G): VARIAN MEDICAL SYSTEMS HAAN GMBH; bergische strasse 16
• Manufacturer Contact: rachel forsberg, ra.qa, mgr ; 501 locust ave; ste 1; charlottesville, VA 22902 ; 4349518635
• MDR Report Key: 4731343
• MDR Text Key: 15317992
• Report Number: 9612638-2015-00001
• Device Sequence Number: 1
• Product Code: JAQ
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: K123815
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Health Professional,User Facility
• Reporter Occupation: Other Health Care Professional
• Type of Report: Initial
• Report Date: 03/26/2015

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 04/24/2015
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: GM11010800
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 03/26/2015
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 10/01/2014
• Is the Device Single Use?: No
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1