PROBLEM TO BE SOLVED: To discriminate between a delayed contrast-enhanced CT image and a coronary artery CT image and to position the delayed contrast-enhanced CT image and the coronary artery CT image accurately, in image processing generating a difference image by performing difference processing by using the coronary artery CT image and the delayed contrast-enhanced CT image.SOLUTION: An image processing method generates a difference image by performing difference processing by using a coronary artery CT image obtained by imaging a left ventricle including a contrasted coronary artery by a CT apparatus and a delay contract-enhanced CT image obtained by imaging the left ventricle including a contrasted cardiac infarction portion by the CT device after the lapse of a predetermined delay time from imaging of the coronary artery CT image. In the method, the coronary artery CT image and the delay contrast-enhanced CT image are obtained, the coronary artery CT image is discriminated from the delay contrast-enhanced CT image, the coronary artery CT image and the delay contrast-enhanced CT image are positioned, and the difference processing for subtracting the coronary artery CT image from the delay contrast-enhanced CT image is performed.SELECTED DRAWING: Figure 1【課題】冠動脈ＣＴ画像と遅延造影ＣＴ画像とを用いた差分処理を行って差分画像を生成する画像処理において、遅延造影ＣＴ画像と冠動脈ＣＴ画像とを判別すると共に、遅延造影ＣＴ画像と冠動脈ＣＴ画像とを正確に位置合わせする。【解決手段】造影された冠動脈を含む左心室をＣＴ装置により撮像して得られた冠動脈ＣＴ画像と、前記冠動脈ＣＴ画像の撮像から所定の遅延時間が経過した後に、造影された心筋梗塞部を含む左心室をＣＴ装置により撮像して得られた遅延造影ＣＴ画像と、を用いた差分処理を行って差分画像を生成する画像処理方法において、前記冠動脈ＣＴ画像と前記遅延造影ＣＴ画像とを取得し、前記冠動脈ＣＴ画像と前記遅延造影ＣＴ画像とを判別し、前記冠動脈ＣＴ画像と前記遅延造影ＣＴ画像との位置合わせを行い、前記遅延造影ＣＴ画像から前記冠動脈ＣＴ画像を差し引く前記差分処理を行う。【選択図】図１
