Philips Research, Hamburg, Germany.
Magn Reson Med. 2011 Jul;66(1):144-53. doi: 10.1002/mrm.22810. Epub 2011 Feb 8.
This work presents a novel method for concurrent estimation of the fractional blood volume and the mean vessel size of tumors based on a multi-gradient-echo-multi-spin-echo sequence and the injection of a super-paramagnetic blood-pool agent. The approach further comprises a post-processing technique for simultaneous estimation of changes in the transverse relaxation rates R(2) and R(2), which is robust against global B(0) and B(1) field inhomogeneities and slice imperfections. The accuracy of the simultaneous ΔR(2) and ΔR(2) quantification approach is evaluated in a phantom. The simultaneous blood volume and vessel size estimates, obtained with MR, compare well to the immunohistological findings in a preclinical experiment (HT1080 cells, implanted in nude mice). Clinical translation is achieved in a patient with a pleomorphic sarcoma in the left pubic bone. The latter demonstrates the robustness of the technique against changes in the contrast agent concentration in blood during washout.
这项工作提出了一种新的方法，用于基于多梯度回波-多自旋回波序列和超顺磁血池造影剂注射，同时估计肿瘤的分数血容量和平均血管大小。该方法进一步包括一种用于同时估计横向弛豫率 R(2)和 R(2)*变化的后处理技术，该技术对全局 B(0)和 B(1)场不均匀性和切片不完美具有鲁棒性。在体模中评估了同时 ΔR(2)和 ΔR(2)*定量方法的准确性。通过磁共振获得的同时血容量和血管大小估计值与临床前实验（植入裸鼠的 HT1080 细胞）中的免疫组织学发现非常吻合。该技术在左侧耻骨多形性肉瘤患者中得到了临床转化。后者证明了该技术对造影剂在洗脱过程中血液浓度变化的稳健性。
