Hope Tuva R, Vardal Jonas, Bjørnerud Atle, Larsson Christopher, Arnesen Marius R, Salo Raimo A, Groote Inge R
Norwegian University of Science and Technology, Trondheim, Norway; The Intervention Centre, Oslo University Hospital Rikshospitalet, Oslo, Norway.
J Magn Reson Imaging. 2015 Feb;41(2):414-23. doi: 10.1002/jmri.24533. Epub 2014 Jan 8.
To study the potential of diffusion tensor imaging (DTI) to serve as a biomarker for radiation-induced brain injury during chemo-radiotherapy (RT) treatment.
Serial DTI data were collected from 18 high-grade glioma (HGG) patients undergoing RT and 7 healthy controls. Changes across time in mean, standard deviation (SD), skewness, and kurtosis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (λa ), and transversal diffusivity (λt ) within the normal-appearing white matter (NAWM) were modeled using a linear mixed-effects model to assess dose dependent changes of five dose bins (0-60 Gy), and global changes compared with a control group.
Mean MD, λa and λt were all significantly increasing in >41 Gy dose regions (0.14%, 0.10%, and 0.18% per week) compared with <12 Gy regions. SD λt had significant dose dependent time evolution of 0.019*dose per week. Mean and SD MD, λa and λt in the global NAWM of the patient group significantly increased (mean; 0.06%, 0.03%, 0.09%, and SD; 0.57%, 0.34%, 0.51 per week) compared with the control group. The changes were significant at week 6 of, or immediately after RT.
DTI is not sensitive to acute global NAWM changes during the treatment of HGG, but sensitive to early posttreatment changes.
研究扩散张量成像（DTI）作为化疗放疗（RT）期间放射性脑损伤生物标志物的潜力。
收集了18例接受RT的高级别胶质瘤（HGG）患者和7名健康对照者的系列DTI数据。使用线性混合效应模型对正常白质（NAWM）内各向异性分数（FA）、平均扩散率（MD）、轴向扩散率（λa）和横向扩散率（λt）的均值、标准差（SD）、偏度和峰度随时间的变化进行建模，以评估五个剂量区间（0 - 60 Gy）的剂量依赖性变化，并与对照组比较整体变化。
与<12 Gy的区域相比，剂量>41 Gy的区域中，平均MD、λa和λt均显著增加（每周分别增加0.14%、0.10%和0.18%）。SD λt具有显著的剂量依赖性时间演变，为每周0.019×剂量。与对照组相比，患者组整体NAWM中的平均和SD MD、λa和λt显著增加（均值；每周0.06%、0.03%、0.09%，标准差；每周0.57%、0.34%、0.51%）。这些变化在RT第6周或RT刚结束时显著。
DTI对HGG治疗期间急性整体NAWM变化不敏感，但对治疗后早期变化敏感。
