Department of Biomedical Engineering, Maastricht University Medical Centre, Maastricht, The Netherlands.
Magn Reson Med. 2010 Apr;63(4):930-9. doi: 10.1002/mrm.22248.
MR vessel size imaging (MR-VSI) is increasingly applied to noninvasively assess microvascular properties of tumors and to evaluate tumor response to antiangiogenic treatment. MR-VSI provides measures for the microvessel radius and fractional blood volume of tumor tissue. However, data have not yet been evaluated with three-dimensional microscopy techniques. Therefore, three-dimensional two-photon laser scanning microscopy (TPLSM) was performed to assess microvascular radius and fractional vessel volume in tumor and muscle tissue. TPLSM data displayed a mazelike architecture of the tumor microvasculature and mainly parallel oriented muscle microvessels. For both MR-VSI and TPLSM, a larger vessel radius and fractional blood volume were found in the tumor rim than in the core. The microvessel radius was approximately six times larger in tumor and muscle for MR-VSI than for TPLSM. The tumor blood volume was 4-fold lower with MR-VSI than with TPLSM, whereas muscle blood volume was comparable for both techniques. Differences between the tumor rim, core, and muscle tissue showed similar trends for both MR-VSI and TPLSM parameters. These results indicate that MR-VSI does not provide absolute measures of microvascular morphology; however, it does reflect heterogeneity in microvascular morphology. Hence, MR-VSI may be used to assess differences in microvascular morphology.
磁共振血管大小成像（MR-VSI）越来越多地应用于无创评估肿瘤的微血管特性，并评估肿瘤对抗血管生成治疗的反应。MR-VSI 提供了肿瘤组织微血管半径和血容量分数的测量值。然而，这些数据尚未用三维显微镜技术进行评估。因此，我们使用三维双光子激光扫描显微镜（TPLSM）来评估肿瘤和肌肉组织中的微血管半径和血管容积分数。TPLSM 数据显示了肿瘤微血管的迷宫样结构，主要是平行排列的肌肉微血管。对于 MR-VSI 和 TPLSM，肿瘤边缘的血管半径和血容量分数都大于肿瘤核心。MR-VSI 测量的肿瘤和肌肉中的微血管半径大约是 TPLSM 的 6 倍。MR-VSI 测量的肿瘤血容量比 TPLSM 低 4 倍，而肌肉血容量在两种技术中相当。MR-VSI 和 TPLSM 参数的肿瘤边缘、核心和肌肉组织之间的差异均表现出相似的趋势。这些结果表明，MR-VSI 不能提供微血管形态的绝对测量值；然而，它确实反映了微血管形态的异质性。因此，MR-VSI 可用于评估微血管形态的差异。
