Elekta of Stockholm, Sweden, introduced its Infinity digital linear accelerator optimized for delivering volumetric intensity modulated arc therapy (VMAT) at the American Society of Therapeutic Radiology and Oncology conference in Los Angeles this week.
VMAT is a very fast intensity modulated radiation therapy (IMRT) treatment delivered in single or multiple arcs, which more precisely targets tumors and protects surrounding tissue, while reducing radiation therapy treatment times, Elekta said.
The VMAT offering improves on existing IMRT technologies and offers a faster alternative to helical tomotherapy. Elekta’s VMAT solution, when used with the firm’s Infinity technology, varies the radiation beam during treatment by simultaneously manipulating the gantry position and speed, multiple-leaf collimator leaves, dose rate and collimator angle.
This provides several distinct advantages over current IMRT techniques, specifically the ability to deliver more radiation to the target while sparing healthy tissue in significantly less time than existing therapies, according to Elekta. In addition, Elekta Infinity combines VMAT with its VolumeView 3D cone beam CT imaging to create high-contrast images with ultra-low dose.
The company said its Infinity modality allows for a total VMAT treatment session in no more than five minutes, including VolumeView 3D cone beam images in three minutes and two minutes of highly conformal arc delivery of radiation. Head and neck treatments – including daily 3D imaging – can be delivered in less than five minutes. Elekta said its Infinity device also protects patients with real-time control point to control point monitoring throughout the treatment process.
Due to the ability of Elekta Infinity to also treat in non-coplanar angles and non-trans-axial planes, the system can yield similar or improved dosimetric performance compared to helical tomotherapy, according to the firm.