title: Improved technique for obtaining teletherapy portal radiographs with high-energy photons.
abstract: H & D curves were obtained for various film/screen combinations exposed to 60Co, 4-MV, and 45-MV photons. Data indicate that contrast is enhanced more by light-emitting screens than by lead screens or direct exposure. Flexible film cassettes are more comfortable for the patient, and extra-large film can be used for larger patients.
mesh_terms: D003037:Cobalt Radioisotopes; D004601:Elementary Particles; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging*; D011859:Radiography; D011867:Radioisotope Teletherapy; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy; D013679:Technology, Radiologic
chemical_list: D003037:Cobalt Radioisotopes