tomoterapi

Tomotherapy is a form of image-guided radiotherapy that delivers intensity-modulated radiation therapy (IMRT) using a helical delivery around a ring-shaped gantry, with integrated imaging to verify patient positioning before and during treatment. It is commonly referred to as tomotherapy and is marketed and described as a unified imaging and treatment system.

The treatment combines a linear accelerator with a rotating gantry and a moving patient couch. As the gantry continuously rotates around the patient, the couch advances through the bore, delivering a modulated fan beam that creates a highly conformal dose distribution. The system also acquires megavoltage computed tomography (MVCT) images for image guidance, enabling daily setup verification and, in some cases, adaptive adjustments to account for anatomical changes.

Indications and advantages. Tomotherapy is used for a range of cancers, particularly when targets have complex shapes or are adjacent to sensitive organs. Its helical delivery pattern enables highly conformal dose distributions and can spare surrounding healthy tissue more effectively than some conventional methods. It is frequently employed for cancers in the head and neck, brain, thorax, abdomen, and pelvis, and is valued for treating extended or irregular volumes.

Limitations and considerations. Treatment times can be longer per session compared with some other radiotherapy techniques, and the equipment is specialized and costly, with limited availability at some centers. Planning requires advanced imaging and computational resources, and not every clinical scenario benefits from tomotherapy compared with alternative radiotherapy approaches.