Segmentation of brain magnetic resonance imaging (MRI) and normalization of gray matter volume (GMV) and white matter volume (WMV).

Representative axial brain image of T1-weighted MRI and segmented images of gray matter, white matter, and cerebrospinal fluid are shown. To normalize for head size variability, GMV and WMV were normalized by dividing by the total intracranial volume, calculated by adding GMV, WMV, and cerebrospinal fluid space volume.本研究展示了代表性的T1加权磁共振成像（T1-weighted MRI）轴位脑部图像，以及灰质（gray matter）、白质（white matter）与脑脊液（cerebrospinal fluid）的分割图像。为校正头部尺寸的个体差异，研究通过将灰质体积（gray matter volume, GMV）与白质体积（white matter volume, WMV）除以由灰质体积、白质体积及脑脊液间隙体积之和计算得到的颅内总容积（total intracranial volume），对二者进行标准化处理。