X线衰减校正对^(18)F-FDG SPECT肿瘤显像图像质量的影响

Effects of X-ray Based Attenuating Correction on Quality of ^(18)F-FDG SPECT Imaging in Oncology

目的探讨X线衰减校正对18F FDGSPECT肿瘤显像图像质量的影响。方法5 3例已知或可疑恶性肿瘤的患者 ,采用Millennium TMVG5型SPECT/CT完成18F FDGSPECT显像。应用迭代法重建 ,获得有X线衰减校正 (AC)和无衰减校正 (NAC)的图像 ,并计算靶与本底放射性比值 (T/B)。结果5 3例患者在AC和NAC组检出同样病灶 16 2个 ,AC和NAC组T/B值分别为 8.4 1± 6 .78和 3.6 8± 2 .72 (P <0 .0 0 1,r=0 .6 97)。同时 ,AC图像的质量明显改善。结论在18F FDGSPECT肿瘤显像时 ,有无X线射线衰减校正对病灶的发现数目没有明显差别 ,但采用X射线衰减校正 ,能够改善图像质量。

Objectives To investigate the effects of X-ray based attenuating correction on 18F-FDG SPECT imaging in oncology .Methods 18F-FDG SPECT imaging in 53 patients with known or suspected malignancies was carried out by Millennium TMVG5 type SPECT/CT. The images with X-ray based attenuating correction (AC) or non-AC (NAC) were reconstructed iteratively by selective substitution and the ratios of target to background (T/B) were calculated in both AC and NAC images.ResultsSimilar 162 lesions from 53 patients were detected in AC and NAC groups. The T/B ratios in AC and NAC groups were 8.41±6.78 and 3.68±2.72, respectively (r=0.697,P<0.001). At the same time, the quality of AC image was improved obviously.ConclusionThere is no significant difference in number of detected lesions between AC and NAC group in 18F-FDG SPECT tumor images. However, X-ray based AC technique can improve the image quality.