Jay E. Reiff PhD, Abstract Co-Author: Consultant, Cianna Medical, Inc

Larry Daugherty MD, Presenter: Nothing to Disclose

Sophia L. Subong MD, Abstract Co-Author: Nothing to Disclose

Paul G. Curcillo MD, Abstract Co-Author: Speakers Bureau, Johnson & Johnson Speakers Bureau, STORZ MEDICAL AG Speakers Bureau, Olympus Corporation Speakers Bureau, HOYA Corporation

Lydia T. Komarnicky MD, Abstract Co-Author: Nothing to Disclose

Purpose/Objective(s): Ultrasound is an often used imaging modality in the operating suite to confirm the placement of brachytherapy applicators used for accelerated partial breast irradiation (APBI). With some devices, the catheters may not be clearly demonstrated on ultrasound. We demonstrate the use of intra-operative fluoroscopy as an easily applied and reproducible technique to confirm adequate expansion of a multi-catheter breast brachytherapy applicator. Materials/Methods: The Strut-Adjusted Volume Implant (SAVITM) is a single-entry brachytherapy device with multiple catheters for use with APBI. Each catheter, or strut, can be loaded with a high dose rate 192Ir source which can dwell in multiple positions to deliver a focused dose of radiation. Optimally the struts will open fully and uniformly from their closed central position to form an ellipsoid filling the lumpectomy cavity. This configuration provides the optimal geometry for the delivery of radiation. Ultrasound is often used to confirm the correct positioning of the opened struts. In some patients, ultrasound does not clearly define all the struts and can be difficult to interpret. The final configuration on follow-up CT scan 48 hours later then demonstrates a less than optimal configuration. Subsequently, we have begun to use intra-operative fluoroscopy as an alternative modality to verify the complete and uniform opening of the applicator. Results: Six patients underwent the standard placement of 3 different sized SAVITM brachytherapy applicators. After the insertion and expansion of the applicators, ultrasound was used to confirm their full and uniform opening. This was followed by intra-operative fluoroscopy imaging. Under ultrasound imaging, there were cases where all the catheters were not clearly demonstrated, and thus adequate expansion could not be confirmed. However, when viewed with intra-operative fluoroscopy, 3 of the applicators were determined not to have opened into an ellipsoid geometry, but rather into a concave configuration. Using fluoroscopy, we were then able to collapse and re-expand the catheters into the ellipsoid configuration recommended. Conclusions: Although adequate dose coverage of the PTV can be achieved despite the non-symmetric spatial distribution of dwell positions, the maximum dose encompassing the entire PTV can be decreased by up to 8%, depending on applicator size. We demonstrate the use of intra-operative fluoroscopy as the preferred operating room imaging tool to confirm the complete and uniform expansion of all the struts of the SAVITM APBI brachytherapy applicator before the conclusion of the procedure.. This will ensure better dose coverage of the breast tissue comprising the PTV surrounding the applicator in these multi-catheter devices.

Reiff, J, Daugherty, L, Subong, S, Curcillo, P, Komarnicky, L, Intraoperative Fluoroscopy for Confirmation of Expansion of a Single Entry Multicatheter Breast Brachytherapy Device.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8500728.html