Carlson Stephanie K, Classic Kelly L, Bender Claire E, Russell Stephen J
Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
Mol Imaging Biol. 2007 Mar-Apr;9(2):78-82. doi: 10.1007/s11307-007-0080-9.
To determine the radiation dose to mouse cancer xenografts from serial micro-computed tomography (CT) examinations.
A nude mouse with a 15-mm subcutaneous pancreatic cancer xenograft in the rightflank was used. Radiation exposure to the subcutaneous tumor and the mouse pancreas (to simulate an orthotopic pancreatic tumor model) was measured using lithium fluoride thermoluminescent dosimeters. Ultrafast micro-CT was performed using 80 kVp, 0.26 mA, 0.156 mm slice thickness, 256 slices, 0.7 mm Al filtration, and 60-second image acquisition time (15 mA second). Micro-CT imaging acquisitions were repeated four times.
We measured consistently low tumor doses (0.014 to 0.02 Gy; average=0.017 Gy) per scan. Orthotopic doses in the region of the pancreas were also consistently low (0.014 to 0.018 Gy; average=0.016 Gy) per scan.
Radiation doses delivered during ultrafast micro-CT serial imaging in the mouse are low and are likely below the threshold to affect tumor growth.
确定连续进行微型计算机断层扫描（CT）检查时小鼠癌异种移植瘤所接受的辐射剂量。
使用一只右侧胁腹有一个15毫米皮下胰腺癌异种移植瘤的裸鼠。使用氟化锂热释光剂量计测量皮下肿瘤和小鼠胰腺（以模拟原位胰腺肿瘤模型）所接受的辐射暴露。使用80 kVp、0.26 mA、0.156毫米层厚、256层、0.7毫米铝滤过和60秒图像采集时间（15毫安秒）进行超快微型CT扫描。微型CT成像采集重复进行4次。
我们测得每次扫描时肿瘤剂量始终较低（0.014至0.02 Gy；平均 = 0.017 Gy）。胰腺区域的原位剂量每次扫描时也始终较低（0.014至0.018 Gy；平均 = 0.016 Gy）。
小鼠超快微型CT连续成像过程中所传递的辐射剂量较低，可能低于影响肿瘤生长的阈值。
