学位論文

ダイバージングSPECTシステムにおける解析的画像再構成に関する研究

jpn

2010-03-24

Not Applicable (or Unknown)

2010-03-24

修士(工学)

工学研究科情報電子工学専攻; 指導教授: 尾川浩一

Single photon emission CT (SPECT) systems with a semiconductor detector have several advantages compared with conventional SPECT systems with a Nal (Tl) seintillation detector in terms of energy resolution and spatial resolution. On the other hand，one of the disadvantages of the detector is a small field- of view, (FOV), and thus we proposed a new SPECT system with a diverging collimator to enlarge the FOV. In this SPECT system with the diverging collimator, the effect of the shadow zone and a truncation problem in the axial direction should be considered. And to cope with this problem，we adopted an FBP-type cone-beam reconstruction algorithm with Radon space interpolation，which was proposed by Yang et al. This method reconstructs more accurate images than the Feldkamp, Davis, Kress (FDK) method or Grangeat's method. In this study we evaluated the images reconstructed with Yang's method applied to the data acquired with a diverging collimator. The results obtained with simulations showed the feasibility of the SPECT system with a semiconductor detector and a diverging collimator.

Thesis