Kiselev V G, Strecker R, Ziyeh S, Speck O, Hennig J
Medical Physics, Department of Diagnostic Radiology, University Hospital Freiburg, Hugstetterstrasse 55, D-79106 Freiburg, Germany.
Magn Reson Med. 2005 Mar;53(3):553-63. doi: 10.1002/mrm.20383.
The relation of contrast-enhanced transverse relaxation rates R2* and R2 provides in vivo mapping of the mean caliber of cerebral vessels. This technique is referred to as vessel size imaging (VSI). Here a quantitative assessment of the vessel caliber in brain tumor patients is presented. The obtained mean vessel size shows sensitivity to the tumor type. A theoretical analysis is given to elucidate the morphological information content of VSI in the context of vessel architecture. The simplification of the theory underlying the data processing results in a systematic overestimation of the vessel caliber. An increase in the magnetic susceptibility of the contrast agent allows for quantitatively more accurate measurements. Quantitative VSI must include measurements of the regional diffusion coefficient and absolute determination of the regional cerebral blood volume.
对比增强横向弛豫率R2*和R2的关系可实现脑血管理论直径的体内成像。该技术被称为血管大小成像（VSI）。本文给出了脑肿瘤患者血管直径的定量评估。所获得的平均血管大小对肿瘤类型具有敏感性。通过理论分析以阐明血管结构背景下VSI的形态学信息含量。数据处理基础理论的简化导致血管直径的系统性高估。造影剂磁化率的增加可实现更准确的定量测量。定量VSI必须包括区域扩散系数的测量以及区域脑血容量的绝对测定。
