Patent ID: 6459769
Filing Date: 2002-10-01
Classification: A61N,G21K

Abstract:
A linear accelerator system for applying radiation treatment, which comprises:a linear accelerator adapted to provide an output beam of radiation having a radiation out field; a first multi-leaf collimator connected to the linear accelerator and having multiple leaves being relatively movable to define a first variable radiation beam field from radiation emitted from the linear accelerator; and a second multi-leaf collimator connected to the linear accelerator and having multiple leaves being relatively movable independent of the first moving multi-leaf collimator to define a second variable radiation beam field from radiation emitted from the linear accelerator wherein a first predetermined size beam dosage of radiation may be delivered to a target treatment site by the linear actuator as defined by the first multi-leaf collimator and thereafter the first multi-leaf collimator is retracted and a second predetermined size beam dosage of radiation, different from the first predetermined size beam, may be delivered to the target treatment site as defined by the second multi-leaf collimator.