Johansen-Berg Heidi, Rushworth Matthew F S
Centre for Functional MRI of the Brain, University of Oxford, Oxford OX39DU, United Kingdom.
Annu Rev Neurosci. 2009;32:75-94. doi: 10.1146/annurev.neuro.051508.135735.
Diffusion imaging can be used to estimate the routes taken by fiber pathways connecting different regions of the living brain. This approach has already supplied novel insights into in vivo human brain anatomy. For example, by detecting where connection patterns change, one can define anatomical borders between cortical regions or subcortical nuclei in the living human brain for the first time. Because diffusion tractography is a relatively new technique, however, it is important to assess its validity critically. We discuss the degree to which diffusion tractography meets the requirements of a technique to assess structural connectivity and how its results compare to those from the gold-standard tract tracing methods in nonhuman animals. We conclude that although tractography offers novel opportunities it also raises significant challenges to be addressed by further validation studies to define precisely the limitations and scope of this exciting new technique.
扩散成像可用于估计连接活体大脑不同区域的纤维束所采取的路径。这种方法已经为活体人类大脑解剖学提供了新的见解。例如，通过检测连接模式的变化位置，人们可以首次在活体人类大脑中定义皮质区域或皮质下核之间的解剖边界。然而，由于扩散张量成像术是一种相对较新的技术，严格评估其有效性很重要。我们讨论了扩散张量成像术在多大程度上满足评估结构连通性技术的要求，以及其结果与非人类动物中黄金标准的束路追踪方法的结果相比如何。我们得出结论，尽管张量成像术提供了新的机会，但它也带来了重大挑战，需要进一步的验证研究来解决，以精确界定这种令人兴奋的新技术的局限性和范围。
