Purpose: A randomized study to investigate the routine use of a simulator-based CT (Sim-CT) for planning purposes.

Materials and methods: 24 patients accepted for pelvic radiotherapy were randomized to receive either a Sim-CT or a DCT planning CT scan. The execution time was measured for different steps in both procedures. A questionnaire was developed to gain information about the psychological status and physical comfort.

Results: The set-up (of hardware, software and patient) took significantly longer for the Sim-CT procedure (p<0.05). An average of 5.7 min was found in comparison with 3.2 min for the DCT group. A similar result (p<0.0005) was observed for the scan time (resp. 15.9 versus 5.1 min). However the total time of the procedure (including patient preparation) was significantly lower (p<0.005) for the Sim-CT group (resp. 21.6 versus 31.7 min). Physical comfort score showed that some patients experienced more discomfort during the Sim-CT procedure than during DCT.

Conclusions: The scan acquisition time and set-up time of Sim-CT procedure was significantly higher than DCT however the total time was less for Sim-CT group. The overall reduction in time with Sim-CT is counterbalanced by increased patient discomfort.