Grachev I D, Berdichevsky D, Rauch S L, Heckers S, Kennedy D N, Caviness V S, Alpert N M
Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, 02114, USA.
Neuroimage. 1999 Feb;9(2):250-68. doi: 10.1006/nimg.1998.0397.
Several groups have developed methods for registering an individual's 3D MRI by deforming a standard template. This achievement leads to many possibilities for segmentation and morphology that will impact nuclear medical research in areas such as activation and receptor studies. Accordingly, there is a need for methods that can assess the accuracy of intersubject registration. We have developed a method based on a set of 128 anatomic landmarks per hemisphere, both cortical and subcortical, that allows assessment of both global and local transformation accuracy. We applied our method to compare the accuracy of two standard methods of intersubject registration, AIR 3.0 with fifth-order polynomial warping and the Talairach stereotaxic transformation (Talairach and Tournoux, 1988). SPGR MRI's (256 x 256 x 160) of six normal subjects (age 18-24 years) were derformed to match a standard template volume. To assess registration accuracy the landmarks were located on both the template volume and the transformed volumes by an experienced neuroanatomist. The resulting list of coordinates was analyzed graphically and by ANOVA to compare the accuracy of the two methods and the results of the manual analysis. ANOVA performed over all 128 landmarks showed that the Woods method was more accurate than Talairach (left hemisphere F = 2.8, P < 0.001 and right hemisphere F =2.4, P < 0.006). The Woods method provided a better brain surface transformation than did Talairach (F = 18.0, P < 0.0001), but as expected there was a smaller difference for subcortical structures and both had an accuracy <1 mm for the majority of subcortical landmarks. Overall, both the Woods and Talairach method located about 70% of landmarks with an error of 3 mm or less. More striking differences were noted for landmark accuracy </=1 mm, where the Woods method located about 40% and Talairach about 23%. These results demonstrate that this anatomically based assessment method can help evaluate new methods of intersubject registration and should be a helpful tool in appreciating regional differences in accuracy. Consistent with expectation, we confirmed that the Woods nonlinear registration method was more accurate than Talairach. Landmark-based anatomic analyses of intersubject registration accuracy offer opportunities to explore the relationship among structure, function and architectonic boundaries in the human brain.
有几个研究小组已经开发出通过变形标准模板来对个体的三维磁共振成像（3D MRI）进行配准的方法。这一成果为分割和形态学研究带来了诸多可能性，将对诸如激活和受体研究等核医学领域的研究产生影响。因此，需要能够评估个体间配准准确性的方法。我们开发了一种基于每侧半球128个解剖学标志点（包括皮质和皮质下标志点）的方法，该方法能够评估整体和局部变换的准确性。我们应用我们的方法来比较两种个体间配准标准方法的准确性，即采用五阶多项式扭曲的AIR 3.0方法和Talairach立体定向变换方法（Talairach和Tournoux，1988年）。对6名正常受试者（年龄18 - 24岁）的扰相梯度回波磁共振成像（SPGR MRI，256×256×160）进行变形处理，以匹配一个标准模板体积。为了评估配准准确性，由一位经验丰富的神经解剖学家在模板体积和变换后的体积上确定标志点的位置。对得到的坐标列表进行图形分析和方差分析，以比较两种方法的准确性以及手动分析的结果。对所有128个标志点进行方差分析表明，Woods方法比Talairach方法更准确（左半球F = 2.8，P < 0.001；右半球F = 2.4，P < 0.006）。与Talairach方法相比，Woods方法在脑表面变换方面表现更好（F = 18.0，P < 0.0001），但正如预期的那样，皮质下结构的差异较小，并且对于大多数皮质下标志点，两种方法的准确性均<1毫米。总体而言，Woods方法和Talairach方法定位的标志点中约70%的误差在3毫米或更小。在标志点准确性≤1毫米方面，差异更为显著，其中Woods方法定位的约为40%，Talairach方法定位的约为23%。这些结果表明，这种基于解剖学的评估方法有助于评估新的个体间配准方法，并且应该是一种有助于认识准确性区域差异的有用工具。正如预期的那样，我们证实Woods非线性配准方法比Talairach方法更准确。基于标志点的个体间配准准确性的解剖学分析为探索人类大脑中结构、功能和结构边界之间的关系提供了机会。
