【摘要】 利用三组模型研究ＳＰＥＣＴ脏器功能容积测定中衰减校正系数、放射性活度、容积大小、放射性缺损区和阈值对容积测定的影响。结果表明，在ＳＰＥＣＴ图像重建过程中，不进行衰减校正测得的容积明显高于模型实际容积，测得的容积随校正系数的增大而减小。当校正系数为０．１时，测得的容积与模型实际容积最接近。放射性活度在３７—１８５ｋＢｑ范围内时，测得的容积没有明显差别（Ｐ＞０．０５）。阈值增加，测得容积减小；当阈值为４８％时，测得的容积与模型实际容积最接近。放射性“冷区”的存在对功能容积的测量无影响。更多还原

【Abstract】 The effects of attenuation correction coefficient, radioactivity, volumedimensions, radio deficit area and threshold on the measurement of organ volumewere investigated using 3 groups of phantom. The results showed that the measuredvolume without attenuation correction was higher than the real volume of phantomsin the reconstruction of SPECT images. The measured volume was getting smaller asthe correction coefficient increased. When correction coefficient’ was 0.1, themeasured volume approximated mostly the real volume of phantom. There was nosignificant change in the measured volumed when radioactivity ranged from 37 to185kBq/mL (P>0.05). The measured volume decreased as threshold increasing andbest results were obtained when the threshold was 48%. The presence of radio deficitarea showed no influence for the determination of functional volume. Conclusions:the best results can be obtained with Change’s attenuation correction method inreconstruction with correction coefficient 0.1 and threshold 48%.更多还原