【摘要】 本文论述了人体组织对γ射线的吸收给ＳＰＥＣＴ图像造成的影响。通过分析对比人体衰减的各种校正办法，提出了我们的新方法：采用偏置的线源和平行缝准直器，产生倾斜的扇形束投影；在同一台ＳＰＥＣＴ上获取透射型和发射型两种数据；从透射型数据重建出人体衰减系数的三维分布图；然后对发射型图像作精确的校正。更多还原

【Abstract】 The SPECT imaging affected by tissue absorption is discussed in the paper. Comparing various methods of attenuation correction, shifted line source and slice collimator were investigated to get oblique fan beam projection together with emission projection from the same SPECT scanner. Then the 3D attenuation map of body is reconstructed from the transmission projection and the emission tomogram is corrected according to the attenuation map.更多还原