Radiation therapy device employing cam pin and cam groove guiding system for controlling movement of linear multi-leaf collimator leaves

摘要

A conformal radiation therapy device is disclosed. A multi- leaf collimator is mounted adjacent the head of a linear accelerator. A pair of spaced guides which define predetermined cam grooves are supported by the patient table. The multi-leaf collimator includes a plurality of longitudinally slidable leaves. Each of the leaves includes a cam pin mounted in a respective cam groove. As the head and multi-leaf collimator rotate relative to the patient, the predetermined cam grooves acting through the cam pins slide the individual leaves to adjust a radiation window for controlling radiation to the patient.