Kim Woo Hyoung, Kim Chang Guhn, Kim Dae-Weung
Department of Nuclear Medicine, Wonkwang University School of Medicine, 344-2 Shinyong-Dong, Iksan, 570-711 Korea.
Department of Nuclear Medicine, Wonkwang University School of Medicine, 344-2 Shinyong-Dong, Iksan, 570-711 Korea ; Institute of Wonkwang Medical Science, 344-2 Shinyong-Dong, Iksan, Korea.
Nucl Med Mol Imaging. 2012 Dec;46(4):294-9. doi: 10.1007/s13139-012-0175-3. Epub 2012 Sep 28.
The aim of this study was to define an optimal CT number range applicable to adipose tissue (AT) measurement in modern PET/CT systems.
CT number (in Hounsfield units, HU) was measured in three different pure AT compartments in 53 patients. CT number range for AT was determined in three different ways, including pixel histogram analysis, to take the effect of partial volume averaging into account. The effect of changing the CT number range for AT on the total AT volume was investigated.
The lower limits for CT number for pure subcutaneous AT, retroperitoneal AT, and visceral AT were -140, -140, and -130 HU, respectively. The corresponding upper limits were -70, -71, and -52 HU. The CT number range for AT using three methods when considering partial volume averaging was -144 to -141 HU to -30 to -33 HU, showing similar values between the three methods. The optimal CT number range for AT based on these data was -140 to -30 HU. Increases in total AT volume of 7.5 % and 1.8 % were found when the upper or lower limit was extended using 10 HU intervals, respectively, compared with the reference range of -140 to -30 HU.
This study demonstrated that the optimal CT number range of AT that is applicable to modern PET/CT systems can be defined as -140 to -30 HU. The use of this CT number range of AT allowed lean body mass to be determined in whole-body F-18 FDG PET/CT studies.
本研究的目的是确定适用于现代PET/CT系统中脂肪组织（AT）测量的最佳CT值范围。
在53例患者的三个不同的纯AT区域测量CT值（以亨氏单位，HU表示）。通过三种不同方法确定AT的CT值范围，包括像素直方图分析，以考虑部分容积平均效应。研究了改变AT的CT值范围对总AT体积的影响。
纯皮下AT、腹膜后AT和内脏AT的CT值下限分别为-140、-140和-130 HU。相应的上限分别为-70、-71和-52 HU。考虑部分容积平均时，三种方法确定的AT的CT值范围为-144至-141 HU至-30至-33 HU，三种方法之间的值相似。基于这些数据，AT的最佳CT值范围为-140至-30 HU。与-140至-30 HU的参考范围相比，当分别以10 HU间隔扩展上限或下限时，总AT体积分别增加了7.5%和1.8%。
本研究表明，适用于现代PET/CT系统的AT的最佳CT值范围可定义为-140至-30 HU。在全身F-18 FDG PET/CT研究中，使用该AT的CT值范围可以确定瘦体重。
