Matsumoto Ken-ichiro, Bernardo Marcelino, Subramanian Sankaran, Choyke Peter, Mitchell James B, Krishna Murali C, Lizak Martin J
Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892-1002, USA.
Magn Reson Med. 2006 Aug;56(2):240-6. doi: 10.1002/mrm.20961.
Enhancement of image intensity, using the T1-weighted spoiled gradient-echo (SPGR) sequence, was measured in SCC tumor implanted in the flank of C3H mice while they were subjected to several types of oxygenation challenges inside a hyperbaric chamber designed and constructed to fit in an MRI resonator. The central portions of the tumor gave a positive enhancement, while the periphery showed signal reduction during both normobaric (NBO) and hyperbaric (HBO) oxygen challenges. In the contralateral normal leg, nearly 70% of the region showed a decrease in intensity, and the rest showed a positive enhancement. The positive signal enhancement was markedly greater under HBO compared to NBO. Calculated R1, R2, and M0 maps from multivariate fitting of images acquired by a multislice multiecho (MSME) sequence with variable TR before, during, and after HBO treatment confirm that the source of SPGR signal enhancement in the tumor is associated with shortening of T1.
在植入C3H小鼠侧腹的鳞状细胞癌（SCC）肿瘤中，使用T1加权扰相梯度回波（SPGR）序列测量图像强度增强情况，同时将小鼠置于为适配MRI谐振器而设计和构建的高压舱内，使其接受几种类型的氧合挑战。在常压（NBO）和高压（HBO）氧挑战期间，肿瘤中央部分呈现正增强，而周边显示信号降低。在对侧正常腿部，近70%的区域强度降低，其余区域呈现正增强。与NBO相比，HBO下的正信号增强明显更大。通过在HBO治疗前、期间和之后使用具有可变重复时间（TR）的多层多回波（MSME）序列采集图像进行多变量拟合计算得到的R1、R2和M0图证实，肿瘤中SPGR信号增强的来源与T1缩短有关。
