PROBLEM TO BE SOLVED: To efficiently perform alignment between a subject and a three-dimensional image with high accuracy.SOLUTION: A first characteristic position acquisition part 1020 acquires positions of a body surface close to a breastbone and a rib of the subject drawn in an MRI image acquired by an MRI image acquisition part 1010. A second characteristic position acquisition part 1040 acquires positions of the body surface close to the breastbone and the rib of the subject by use of a measurement value acquired by a measurement value acquisition part 1030. A conversion rule calculation part 1050 calculates a conversion rule of positional coordinates between a sensor coordinate system and an MRI image coordinate system based on information acquired by the first characteristic position acquisition part 1020 and information acquired by the second characteristic position acquisition part.COPYRIGHT: (C)2013,JPO&INPIT【課題】 被検者と３次元画像との位置合わせを効率的かつ精度よく行う。【解決手段】 第１特徴位置取得部１０２０は、ＭＲＩ画像取得部１０１０が取得したＭＲＩ画像に描出される被検体の胸骨および肋骨に近接する体表の位置を取得する。第２特徴位置取得部１０４０は、計測値取得部１０３０が取得した計測値を利用して、被検体の胸骨および肋骨に近接する体表の位置を取得する。変換規則算出部１０５０は、第１特徴位置取得部１０２０が取得した情報と、第２特徴位置取得部が取得した情報とに基づき、センサ座標系とＭＲＩ画像座標系との間の位置座標の変換規則を算出する。【選択図】 図１
