Compensating for tumor motion by a 6-degree-of-freedom treatment couch: is patient tolerance an issue?

PURPOSE: To determine whether patients could tolerate the motion of a robotic couch that compensates for breathing-induced tumor motion.

METHODS AND MATERIALS: A total of 10 healthy subjects and 23 radio-oncology patients underwent simulated extracranial stereotactic radiotherapy (two 30-min sessions) on a robotic couch programmed to follow a fictitious tumor trajectory of 20x5x5 mm (cranio-caudal, left-right, and anterior-posterior directions, respectively) while rotating 2 degrees around a cranio-caudal axis at a frequency of 5 seconds per loop.

RESULTS

No session had to be interrupted and no nausea was induced. However, one patient refused the second session due to general deterioration and not all patients could keep their arms elevated for the entire session.

CONCLUSIONS

Our findings showed that most patients tolerated compensatory couch motion and that motion sickness should not pose a problem in the investigation of this tumor-tracking method.