title: Spherical lead shields for megavoltage teletherapy.
abstract: A new method of manufacturing individualized, focused lead shields for megavoltage teletherapy is described. Computerized film dosimetry demonstrated that in contrast to nonfocused shields, the new focused shields exhibit good maintenance of penumbra width as the distance between the edge of the beam and the central axis is increased.
mesh_terms: D006801:Humans; D011835:Radiation Protection / Q000295:instrumentation*; D011867:Radioisotope Teletherapy / Q000295:instrumentation*; D011882:Radiotherapy, High-Energy