Thompson P M, Schwartz C, Lin R T, Khan A A, Toga A W
Laboratory of Neuro Imaging, Department of Neurology, Division of Brain Mapping, UCLA School of Medicine, Los Angeles, California 90095, USA.
J Neurosci. 1996 Jul 1;16(13):4261-74. doi: 10.1523/JNEUROSCI.16-13-04261.1996.
Morphometric variance of the human brain is qualitatively observable in surface features of the cortex. Statistical analysis of sulcal geometry will facilitate multisubject atlasing, neurosurgical studies, and multimodality brain mapping applications. This investigation describes the variability in location and geometry of five sulci surveyed in each hemisphere of six postmortem human brains placed within the Talairach stereotaxic grid. The sulci were modeled as complex internal surfaces in the brain. Heterogeneous profiles of three-dimensional (3D) variation were quantified locally within individual sulci. Whole human heads, sectioned at 50 micrometer, were digitally photographed and high-resolution 3D data volumes were reconstructed. The parieto-occipital sulcus, the anterior and posterior rami of the calcarine sulcus, the cingulate and marginal sulci, and the supracallosal sulcus were delineated manually on sagittally resampled sections. Sulcal outlines were reparameterized for surface comparisons. Statistics of 3D variation for arbitrary points on each surface were calculated locally from the standardized individual data. Additional measures of surface area, extent in three dimensions, surface curvature, and fractal dimension were used to characterize variations in sulcal geometry. Paralimbic sulci exhibited a greater degree of anterior-posterior variability than vertical variability. Occipital sulci displayed the reverse trend. Both trends were consistent with developmental growth patterns. Points on the occipital sulci displayed a profile of variability highly correlated with their 3D distance from the posterior commissure. Surface curvature was greater for the arched paralimbic sulci than for those bounding occipital gyri in each hemisphere. On the other hand, fractal dimension measures were remarkably similar for all sulci examined, and no significant hemispheric asymmetries were found for any of the selected spatial and geometric parameters. Implications of cortical morphometric variability for multisubject comparisons and brain mapping applications are discussed.
人类大脑的形态计量学差异在皮质表面特征中可定性观察到。脑沟几何形状的统计分析将有助于多主体图谱绘制、神经外科研究以及多模态脑图谱应用。本研究描述了放置在Talairach立体定向网格中的六具人类尸体大脑每个半球中所测量的五条脑沟在位置和几何形状上的变异性。这些脑沟被建模为大脑中的复杂内表面。在各个脑沟内局部量化了三维（3D）变化的异质轮廓。对切成50微米厚切片的整个人类头部进行数码拍照，并重建高分辨率3D数据体。在矢状面重采样切片上手动勾勒出顶枕沟、距状沟的前后支、扣带沟和缘上沟以及胼胝体上沟。为了进行表面比较，对脑沟轮廓进行了重新参数化。根据标准化的个体数据在局部计算每个表面上任意点的3D变化统计量。使用表面积、三维范围、表面曲率和分形维数等额外测量方法来表征脑沟几何形状的变化。边缘旁脑沟在前后方向上的变异性程度大于垂直方向的变异性。枕叶脑沟呈现相反的趋势。这两种趋势都与发育生长模式一致。枕叶脑沟上的点显示出与其距后连合的3D距离高度相关的变异性轮廓。在每个半球中，拱形边缘旁脑沟的表面曲率大于界定枕叶回的脑沟。另一方面，所有检查的脑沟的分形维数测量结果非常相似，并且对于任何选定的空间和几何参数都未发现明显的半球不对称性。讨论了皮质形态计量学变异性对多主体比较和脑图谱应用的影响。
