Clinical Application of a New 3-D Treatment Planning System, the CT Simulator

Radiotherapy treatment p lanning (RTP) has been performed with a new system, the CT Simulator, in 312 patients. With this system, RTP from the time of CT scanning until f ield projection could be performed in a short period of time. Various threedimens ionally reconstructed images were found to be useful, such as target outlines over the scannograms, a beam's eye view with beam marks over multiple CT slices, reconstructed CT images with dose-distributio n curves, simulation images for verification, and dose-volume spectra for optimization of radiotherapy, In clinical use, the treatment of posttumorectomy breast cancer, maxillary cancer, nasopharyngeal cancer, osseous and soft tissue sarcoma, lung cancer, brain and orbital tumors, respiratory gating irradiation were found to be benefit from 3-D planning,