Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada.
Neuroimage. 2010 Jan 15;49(2):1224-30. doi: 10.1016/j.neuroimage.2009.09.042. Epub 2009 Sep 26.
Several neuropsychiatric disorders involving hippocampal structural changes have been studied extensively using volumetric magnetic resonance imaging (MRI). These studies have mostly measured total hippocampal volume while the present study aimed to delineate and measure hippocampal subfields within the whole hippocampus and subdivisions along its longitudinal axis. Images were acquired at 4.7 T in 11 healthy subjects (5 males and 6 females, aged 23-56 years), using a fast spin echo (FSE) sequence with 0.52 x 0.68 x 1.0 mm(3) native resolution, collecting 90 contiguous coronal slices. Subiculum, cornu ammonis (CA1-3), and dentate gyrus were traced manually within the hippocampal head, body, and tail. We reported volumes for the subfields and demonstrated differences in the distribution within the hippocampus and its parts. The biggest part of the dentate gyrus was located in the hippocampal body, following the hippocampal head and tail. In contrast, the hippocampal head had the largest part of CA1-3, following the hippocampal body and tail. The hippocampal tail had the smallest portion of the subiculum compared to hippocampal head and tail. Subfield volumes were consistent between hemispheres and showed distributions within the longitudinal subdivisions that were consistent with histological data. Direct measurements of subfield distribution along the longitudinal axis of the hippocampus may be more sensitive to detecting disease effects than total volume measures and the differential distribution of subfield volumes may aid in the interpretation of measurements obtained at lower field strength and spatial resolution.
已有多项研究使用容积磁共振成像（MRI）对涉及海马结构变化的多种神经精神疾病进行了广泛研究。这些研究主要测量了总海马体积，而本研究旨在描绘和测量整个海马内的海马亚区以及其长轴上的细分部分。在 11 名健康受试者（5 名男性和 6 名女性，年龄 23-56 岁）中，在 4.7T 场强下使用快速自旋回波（FSE）序列采集图像，分辨率为 0.52 x 0.68 x 1.0mm(3)，采集 90 个连续的冠状切片。在海马头、体和尾部内手动追踪下托、角回（CA1-3）和齿状回。我们报告了亚区的体积，并展示了海马及其各部分内的分布差异。最大的齿状回部分位于海马体，其次是海马头和尾部。相比之下，海马头内 CA1-3 的部分最大，其次是海马体和尾部。与海马头和尾部相比，海马尾部的下托部分最小。亚区体积在两侧半球之间具有一致性，并且在与组织学数据一致的长轴细分部分内具有分布。与总体积测量相比，沿海马体长轴直接测量亚区分布可能更能敏感地检测到疾病的影响，并且亚区体积的差异分布可能有助于解释在较低场强和空间分辨率下获得的测量值。
