Comparison of methods of attenuation and scatter correction in brain perfusion SPECT.
Comparison of methods of attenuation and scatter correction in brain perfusion SPECT.
复制标题
脑灌注 SPECT 中衰减和散射校正方法的比较。
DOI：
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发表时间：
2005
影响因子：
1.3
通讯作者：
I. Narabayashi
中科院分区：
文献类型：
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作者：
M. Hayashi;J. Deguchi;K. Utsunomiya;M. Yamada;T. Komori;Masayasu Takeuchi;K. Kanna;I. Narabayashi
客观化
为了准确测量脑血流量(CBF)，必须准确测定放射性计数在脑内的分布。散射和衰减是影响确定脑内放射性计数准确性的因素。
方法
我们用放射自显影的方法，用N-异丙基-对-[123I]碘苯丙胺对患者的局部脑血流量进行了比较，首先，在SPECT图像上用经验值进行均匀衰减校正(张法)；其次，进行散射校正，并用均匀衰减水体的MU值进行衰减校正(三能窗[Tew]+Chang法)；第三，进行散射校正，用CT计算的MU值进行衰减校正(Tew+CT法)。我们还将这些方法测量的局部CBF与使用CT和稳定氙气的氙气CT/CBF方法测得的值进行了比较。
结果
散射校正减少了对枯水区局部CBF的高估。与氙气CT/CBF方法相比，Tew+CT方法具有更好的局部和整体相关性。
结论
Tew+CT校正方法对局部脑血流量的测量最为准确。
OBJECTIVE
The radioactivity count distribution in the brain must be determined accurately to accurately measure cerebral blood flow (CBF). Scatter and attenuation are factors that compromise the accuracy of determining radioactivity counts in the brain.
METHODS
We compared regional CBF in patients by an autoradiographic method using N-isopropyl-p-[123I] iodoamphetamine when, first, attenuation correction alone was performed uniformly on SPECT images by using empiric mu-values (Chang method); second, scatter correction was performed and the mu-values of a homogeneous-attenuation body of water were used for attenuation correction (triple-energy window [TEW]+Chang method); and third, scatter correction was performed and the mu-values calculated by CT were used for attenuation correction (TEW+CT method). We also compared regional CBF measured by these methods with the values obtained by the xenon CT/CBF method, which uses CT and stable xenon.
RESULTS
Scatter correction reduced overestimation of regional CBF in low-flow regions. The TEW+CT method yielded better regional and overall correlations with the xenon CT/CBF method than did either of the other methods.
CONCLUSION
The TEW+CT method of correction gave the most accurate measurements of regional CBF.