Session Item

For many treatment indications in radiation oncology, it has become clinical standard to use additional MRI information for more accurate target delineation. MRI has may benefits, including superior soft tissue contrast and the possibility for additional functional imaging without any imaging dose exposure. It does not directly provide, however, the electron density information necessary for precise dose calculation.

In the last years, there has been increasing interest in MRI-only treatment planning workflows, where a CT scan for treatment planning is completely omitted. It has been shown that, for specific body sites, such workflows are feasible using conventional linacs with X-ray and Cone-Beam CT based image guidance, and the topic has gained even more interest with the clinical introduction of MRI-linacs,

This presentation will give an overview over the different methods to generate psuedo-CTs from MR images, focusing on different clinically applied workflows published by several groups and achievable dose calculation presicion, current status and directions of ongoing research in the area of MRI-only treatment planning, as well as available commercial solutions. Lastly, the impact of MR image quality and consequential QA recommendations for MR imaging in the context of MRI-only radiotherapy will be discussed.