Empieza el Noviembre 15, 2017 15:30
3D imaging techniques are used in brachytherapy for pre-planning brachytherapy implants, guiding the applicator insertion, and treatment planning. In the case of cervix cancer the development of magnetic resonsnance image-guided adaptive brachytherapy has lead to improved clinical outcome in terms of local control, and morbidity. Interfraction variations related to anatomical variations between the BT applicator and nearby organs at risk have been identified as the largest source for dosimetric uncertainties in prescribed vs. delivered dose. Therefore repetitive 3D imaging is currently recommended for dose plan adaptations to the anatomy of each treatment fraction. In settings with limited access to MRI, multiple workflows for combinations of imaging modalities have been suggested to optimize the quality of target delineation and allow for high-quality adaptive treatment planning. Different options to combine MRI and CT-imaging will be discussed in this presentation.
Ultrasound is an imaging techique that receives more attention for gynaecological brachytherapy. Transrectal ultrasound allows for excellent target depiction during applicator implantation and may be a suitable alternative to CT-based target definition, which tends to systematically overestimate the high-risk clinical target volume. A technique to combine ultrasound- and CT-imaging for treatment planning is currently under development at the Medical University of Vienna, and will be discussed in this presentation.