Room: Exhibit Hall
Purpose: HDR surface applicators used in brachytherapy for skin lesions offer superior dose distribution where other treatment modalities may be inadequate. For instance, large superficial tumors in highly curved areas when treated with electrons may be prone to non-uniform dose distributions due to the difficulty in matching abutting electron fields. Although the current design for flap applicators have shown acceptable results, each has some shortcomings, with respect to their ease of use, cost, flexibility, and dose distribution. Some clinics resort to patient specific custom applicators to address these issues, but limited biomaterial availability and lack of clinical resources have restricted their widespread use.
Methods: Newly developed surface applicators (TrueDose) were designed to address shortcomings associated with current flap applicators while retaining their flexibility for optimal skin-conformality. In this work, several FDA approved materials were analyzed to create an improved flap applicator. Each applicator was tested for consistency, integrity and flexibility. Finally, phantom based dosimetry studies were conducted using films for comparison of dose distribution against currently available applicators.
Results: Dosimetric evaluation of the TrueDose applicator showed improvements in dose distribution when the TPS algorithm accounts for heterogeneities caused by air gaps. The applicators were also tested for dimensional accuracy to ensure a constant distance from the catheter plane to the skin-surface. These applicators were also analyzed for material biocompatibility as well as tissue equivalence which confirmed their safe implementation in the clinic.
Conclusion: TrueDose flap applicators for HDR surface brachytherapy have been designed. These applicators offer ease of use, low cost, custom shaping to any size lesion, conformality around curved surfaces, and superior dose distribution.
Dose Uniformity, Surface Dose, HDR