Room: AAPM ePoster Library
Heavy patients with body weight close to or above 400 lbs present unique challenges in radiation therapy since the weight limit of most treatment couches reduces as the couch-top is extended toward the treatment gantry. The purpose of this work was to develop a small footprint couch-top support platform to safely perform image-guided radiotherapy (IGRT) for extremely heavy patients.
One way to protect the couch-top from structural damage and prevent catastrophic breakdown is to provide additional support as the couch-top extends toward the treatment gantry. To allow maximal range of gantry movement, a small-footprint adjustable jack stand, placed underneath the couch-top, was chosen as an additional support platform. The support platform was made of a commercial jack stand (with 1100lb capacity) and a modified 8-ball transfer roller (with 400 lb capacity) mounted at the top. With the couch-top resting on top of the transfer rollers, the couch-top can be easily extended longitudinally and laterally. The operation of the couch-top support platform was tested with simulated weight load (phantom). KV and MV imaging options and ranges were quantified.
With simulated heavy patient weight load, the newly constructed couch-top support platform was found to provide stable support with smooth couch shifts. The small footprint allowed gantry rotation from 133° to 313°, which would allow both fixed beam and partial-arc VMAT radiotherapy. For IGRT, orthogonal 2D KV-KV image pairs with source angles of 40° and 130° were acquired and tested successfully. The study demonstrated the potential of using this new couch-top support platform to prevent couch failure from heavy patients.
A new couch-top support platform has been designed, assembled, and tested for IGRT. The new support platform is easy to use, cost effective and would allow heavy patients to be safely treated with image guided radiotherapy.