CT for intracavitary radiotherapy planning.

Twenty-two patients with malignant uterine tumors were examined with computed tomography (CT) for treatment planning after insertion of an afterloading Fletcher applicator. The CT findings maximized the individualization of treatment planning, including the number, dosage, and loading arrangement of radioactive sources. Artifacts were produced by the metal; but in most cases the scans accurately portrayed the three-dimensional anatomic relationship of the applicator, uterus, and neighboring vital structures. The CT information made it possible to calculate dose distribution more rapidly and accurately for both intracavitary therapy and combined intracavitary and external therapy. Unsuspected uterine perforation was detected by CT in one case.