TomoTherapy: implications on daily workload and scheduling patients.

Purpose: The aim of the study was to measure the mean duration of treatments and to investigate the occasional events, with extreme influence on treatment time.
Patients and Methods: Time measurements were performed from the start of patient treatments (n=72) and one year later (n=27) on TomoTherapy. The time interval of the different procedures during treatment was measured. The cause of extra long treatment time was examined. All patients received a MV-CT scan prior to treatment.
Results: The mean overall total treatment time per localization ranged from 21.3 to 27.4 min. In 4.1% of the total population extreme long time measurements have been observed, interruptions due to equipment malfunction being the main cause (57.5%). Comparison between time measurements performed after clinical implementation and time measurements performed one year later to examine the learning curve, showed no differences.
Conclusion: Treating a patient on TomoTherapy takes approximately 25 min, yielding 19 patients to be treated within 8 h. However, occasional treatment interruptions and variations in time of irradiation have a certain impact on daily patient scheduling for treatment, and influences the workload from day-to-day.