PROBLEM TO BE SOLVED: To provide a therapy planning device that acquires a scanning path shortening a scanning time and also considering avoidance of irradiation to normal tissues and vital organs.SOLUTION: The therapy planning device includes: a scanning path candidate extraction unit for previously extracting a plurality of candidates for scanning paths that connect all of the spot positions in a single layer； a scanning path evaluation unit for evaluating each scanning path on the basis of a time required for scanning a charged-particle beam in each of the plurality of scanning path candidates previously extracted by the scanning path candidate extraction unit； and a scanning path determination unit for determining the scanning path to be used for the therapy, on the basis of the result of the evaluation by the scanning path evaluation unit.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2017,JPO&INPIT【課題】走査時間を短縮し、かつ、正常組織や重要臓器への照射回避も考慮した走査経路を求めるための治療計画装置を得ること。【解決手段】一レイヤー内の全てのスポット位置を結ぶ走査経路の複数の候補を予め抽出する走査経路候補抽出部と、走査経路候補抽出部が予め抽出した複数の候補の走査経路のそれぞれにおける荷電粒子ビームを走査するのに費やされる時間に基づいて、それぞれの走査経路を評価する走査経路評価部と、この走査経路評価部において評価した結果に基づいて、治療時に用いる走査経路を決定する走査経路決定部とを備えるようにした。【選択図】図１
