PROBLEM TO BE SOLVED: To understand a state on an approaching path of a treatment tool to a structure masked by the other structure such as a lesion in an organ more easily.SOLUTION: A projection image generation apparatus equipped with a projection image generation part 17 for generating a projection image formed by projecting image information on a plurality of visual lines viewing a first structure in a three-dimensional medical image from a given viewpoint on a given projection plane includes: a treatment tool position setting part 13 for setting an assumed position of the treatment tool in the tree-dimensional medical image a surface detection part 15 for detecting a surface of the first structure from the three-dimensional medical image a lesion position specifying part 14 for specifying a second structure (for example, a lesion) located at a position masked by the first structure indicated in the three-dimensional image and an intersection point detecting part 16 for detecting an intersection point PA between an assumed path formed when the treatment tool is approached from the assumed position to the second structure and the surface of the first structure. The part 17 displays the intersection point PA in an identifiable manner at a position to which the image information on the visual line connecting the viewpoint and the intersection point PA is projected.COPYRIGHT: (C)2012,JPO&INPIT【課題】臓器中の病変のように他の構造物によって遮蔽された構造物に対する処置具の接近経路上の様子をより容易に把握できるようにする。【解決手段】3次元医用画像中の第1構造物を所与の視点から見る複数の視線上の画像情報を所与の投影面に投影した投影画像を生成する投影画像生成部17を備えた投影画像生成装置に、3次元医用画像中に処置具の想定位置を設定する処置具位置設定部13と、3次元医用画像から第1構造物の表面を検出する表面検出部15と、3次元医用画像に表された、第1構造物によって遮蔽される位置にある第2構造物(例えば病変)を特定する病変位置特定部14と、処置具を想定位置から第2構造物に接近させる際の想定経路と第1構造物の表面との交点PAを検出する交点検出部16とを設け、投影画像生成部17が、視点と交点PAとを結ぶ視線上の画像情報が投影される位置に、交点PAを識別可能な態様で表すようにした。【選択図】図2
