TomoHelicalTM, the TomoTherapy® System’s flagship helical mode of treatment that has been in use for almost a decade, combines 360 degree fan-beam delivery of intensity-modulated radiation therapy (IMRT) and megavoltage CT (MVCT) imaging for a gold-standard treatment and targeting of complex tumors. During treatment delivery, the linear accelerator completes multiple 360-degree rotations around the patient while the couch passes through the center bore of the system. And, with its continuous, high dose rate delivery, beam-on times are short compared with many other types of radiation treatment.
TomoHelical gives you the ability to intricately modulate radiation dose intensity, along with delivery angle across three dimensions, to produce conformal dose distributions. It enables the delivery of thousands of narrow beamlets, which are individually optimized to target the tumor. The TomoHelical mode maximizes conformality and uniformity of dose to the tumor while minimizing exposure to healthy tissue. With TomoHelical, the user is able to create a treatment plan that defines dose goals for the targeted tumor, dose constraints for structures that must be avoided, the level of modulation for the plan and the fractionation schedule.