Patent ID: 7780349
Filing Date: 2010-08-24
Classification: A61B,A61N

Abstract:
1. A method, comprising: providing a LINAC with a radiation source having a beam central axis from which a treatment beam is emitted; providing radio-opaque markers aligned within the LINAC's beam central axis, at a fixed distance from each other and at a predefined distance from the radiation source of the LINAC; providing a housing for said radio-opaque markers that maintains their position relative to each other and the radiation source of the LINAC; providing a means of attachment of the housing to the LINAC; providing a radiographic image guidance system which is independent of the LINAC; positioning the radio-opaque markers which are attached to the LINAC at a fixed distance from each other, and at a fixed distance from the LINAC's radiation source and aligned with the LINAC's beam central axis such that the radio-opaque markers' position in space give a physical representation of the beam central axis; positioning the LINAC to a series of pre-defined positions; generating stereotactic images of the radio-opaque markers at each pre-defined position using the radiographic image guided system which is independent of the LINAC; analyzing the coordinates of the radio-opaque markers from the acquired images and calculating angular and distal parameters of each beam position to obtain beam geometry parameters where the coordinates of the radio-opaque markers are represented by values x comparing and assessing the obtained beam geometry parameters with the values of the pre-defined beam positions.