公开(公告)号：US20150301202A1

公开(公告)日：2015-10-22

申请号：US14687948

申请日：2015-04-16

Applicant: Hitachi, Ltd.

Inventor： Hiroyuki TAKAGI ,  Isao MURATA

IPC: G01T1/36 ,  G01N23/04

CPC classification number: G01T1/36 ,  A61B6/032 ,  A61B6/482 ,  A61B6/583 ,  G01N23/046

Abstract: Provided is an X-ray energy spectrum estimation method capable of reproducing, with high precision, information on an attenuation path to which an X-ray is irradiated, and performing, with high precision, reconstruction of an X-ray CT image by enabling high-precision estimation of spectrum of energy released from an X-ray source device. An energy spectrum estimation device (92) normalizes a response function, and calculates a modified efficiency matrix from the normalized response function, a detection efficiency matrix, and a measurement-system correction coefficient. The energy spectrum estimation device then calculates a particular result in accordance with a Bayesian estimation equation, without divergence, with use of the calculated modified efficiency matrix, the normalized modified efficiency matrix, and an attenuation characteristic curve obtained by a measurement circuit (30). The energy spectrum (92) calculates an X-ray energy spectrum by dividing, by the normalized modified efficiency matrix, the particular result obtained by the Bayesian estimation equation.

Abstract translation: 本发明提供能够高精度地再现X射线照射的衰减路径上的信息，以高精度进行X射线CT图像重建的X射线能谱估计方法， - 从X射线源装置释放的能量谱的精确估计。 能量谱估计装置（92）对响应函数进行归一化，并根据归一化响应函数，检测效率矩阵和测量系统校正系数来计算修正效率矩阵。 能谱估计装置然后利用计算出的修正效率矩阵，归一化修正效率矩阵和由测量电路（30）获得的衰减特性曲线，根据贝叶斯估计方程而不发散地计算特定结果。 能谱（92）通过归一化修正效率矩阵除以由贝叶斯估计方程获得的特定结果来计算X射线能谱。