An image processing apparatus capable of generating a folded three-dimensional image is deformed into a shape, such as folded cuff clothing shape hollow organ, is exposed to the outside the inner surface of the portion of the hollow organ, and displays To provide, CPU101 of the image processing apparatus 100 includes a plurality of along the center line of the tubular organ 50 or plane 20, including a plurality of line-of-sight vector 23 of any hollow organ 50, which is extracted from the volume image 40 The coordinate transformation along the (circle 30, for example) convex predetermined is divided in a plane, with each plane 20, set on the outside of the hollow organ 50 points inside the luminal organ 50, the corresponding point coordinate converted I give the pixel values of the original position. Generates a folded volume image by combining the reverse procedure of the procedure by dividing the respective planes 20 and then, it is projected onto the projection plane from the viewing direction in any of the folded volume image, to generate a folded three-dimensional image 90 to the shading on the display unit 107 in.管腔臓器の形状を服の袖口を折返したような形状に変形させ、管腔臓器の一部の内面を外側に露出させた折返し3次元画像を生成、表示することが可能な画像処理装置を提供するために、画像処理装置100のCPU101は、ボリューム画像40から抽出された管腔臓器50を任意の視線ベクトル23を含む複数の平面20、または管腔臓器50の中心線に沿った複数の平面で分割し、各平面20上で、管腔臓器50の内部の点を管腔臓器50の外側に設定した所定の凸面(例えば円30)に沿って座標変換し、座標変換後の対応点に元の位置の画素値を与える。次に各平面20を分割した手順の逆の手順で合成して折返しボリューム画像を生成し、この折返しボリューム画像を任意の視点方向から投影面に投影し、陰影付けした折返し3次元画像90を生成して表示装置107に表示する。
