Being the observation device in order to observe the multi leaf

摘要

PROBLEM TO BE SOLVED: To provide a multileaf collimator observation device and a radiotherapy apparatus which are easily and higly precisely observing the shape of a leaf opening of a multileaf collimator (MLC).;SOLUTION: The observation device which has a plurality of movable leaves 31, is rotatably held around an axis of a treatment beam BM to observe the MLC 3 and specifies an irradiation field of radiation from a radiation source, is provided with: an imaging part 4 which is provided on the radiation source side of the MLC 3 to pick up the leaf opening shape of the MLC 3; a rotational angle detection part 5 to detect a rotational angle around an irradiation axis of the MLC 3; and a data processing part DP to store, calculate, and display data. The data processing part DP includes: a coordinate transformation means 6 for performing coordinate transformation of the leaf opening shape of treatment plan data preliminarily stored based on the rotational angle detected by the rotational angle detection part 5; a visual collation means 7 for displaying the reference leaf opening shape to which the coordinate transformation is performed and the actual leaf opening shape picked up by the imaging part for visual collation; and an image processing collation means 8 for collating the reference leaf opening shape and the actual leaf opening shape by image processing.;COPYRIGHT: (C)2011,JPO&INPIT