Middlebrooks Erik H, Quisling Ronald G, King Michael A, Carney Paul R, Roper Steven, Colon-Perez Luis M, Mareci Thomas H
Department of Radiology, University of Alabama at Birmingham, 619 19th St. S., JT N409, Birmingham, AL, 35249, USA.
Department of Radiology, University of Florida, Gainesville, FL, USA.
Surg Radiol Anat. 2017 Oct;39(10):1149-1159. doi: 10.1007/s00276-017-1843-x. Epub 2017 Mar 12.
The hippocampus has a critical role in many common disease processes. Currently, routine 3 Tesla structural MRI is a mainstay of clinical diagnosis. The goal of our study is to evaluate the normal variability in size and/or conspicuity of the hippocampal subcomponents in routine clinical 3 Tesla high-resolution T2-weighted images to provide a basis for better defining pathological derangements. Additionally, we utilize diffusion data acquired from a 17.6 Tesla MRI of the hippocampus as a benchmark to better illustrate these subcomponents.
The hippocampus was retrospectively assessed on 104 clinically normal patients undergoing coronal T2-weighted imaging. The conspicuity of the majority of hippocampal subcomponents was assessed in each portion of the hippocampus. Additionally, easily applicable cross-sectional measurements and signal intensities were obtained to evaluate the range of normal, as well as inter- and intra-subject variability.
The normal range of cross-sectional measurements of the hippocampal subcomponents was calculated. There was minimal side-to-side variability in cross-sectional measurements of hippocampal subcomponents (< 5%) with the exception of the subiculum (R>L by 8.3%) and the CA4/DG (R>L by 5.8%). The internal architecture showed high variability in visibility of subcomponents between different segments of the hippocampus.
Confident clinical assessment of the hippocampus requires a thorough knowledge of hippocampal size and signal, but also the internal architecture expected to be seen. The data provided in this study will provide the reader with vital information necessary for distinguishing a normal from abnormal exam.
海马体在许多常见疾病过程中起着关键作用。目前，常规3特斯拉结构磁共振成像（MRI）是临床诊断的主要手段。我们研究的目的是评估常规临床3特斯拉高分辨率T2加权图像中海马体亚成分大小和/或清晰度的正常变异性，以便为更好地界定病理紊乱提供依据。此外，我们利用从17.6特斯拉海马体MRI获取的扩散数据作为基准，以更好地阐明这些亚成分。
对104例接受冠状位T2加权成像的临床正常患者的海马体进行回顾性评估。在海马体的每个部分评估大多数海马体亚成分的清晰度。此外，还获得了易于应用的横断面测量值和信号强度，以评估正常范围以及个体间和个体内的变异性。
计算了海马体亚成分横断面测量的正常范围。海马体亚成分的横断面测量值左右变异性极小（<5%），但下托（右侧大于左侧8.3%）和CA4/齿状回（右侧大于左侧5.8%）除外。内部结构显示海马体不同节段之间亚成分的可见性存在高度变异性。
对海马体进行可靠的临床评估不仅需要全面了解海马体的大小和信号，还需要了解预期可见的内部结构。本研究提供的数据将为读者提供区分正常检查与异常检查所需的重要信息。
