Lye T C, Grayson D A, Creasey H, Piguet O, Bennett H P, Ridley L J, Kril J J, Broe G A
Centre for Education and Research on Ageing, The University of Sydney and Concord Hospital, Sydney, New South Wales, Australia.
Neuroradiology. 2006 Feb;48(2):90-9. doi: 10.1007/s00234-005-0032-5. Epub 2005 Dec 20.
A number of different methods have been employed to correct hippocampal volumes for individual variation in head size. Researchers have previously used qualitative visual inspection to gauge hippocampal atrophy. The purpose of this study was to determine the best measure(s) of hippocampal size for predicting memory functioning in 102 community-dwelling individuals over 80 years of age. Hippocampal size was estimated using magnetic resonance imaging (MRI) volumetry and qualitative visual assessment. Right and left hippocampal volumes were adjusted by three different estimates of head size: total intracranial volume (TICV), whole-brain volume including ventricles (WB+V) and a more refined measure of whole-brain volume with ventricles extracted (WB). We compared the relative efficacy of these three volumetric adjustment methods and visual ratings of hippocampal size in predicting memory performance using linear regression. All four measures of hippocampal size were significant predictors of memory performance. TICV-adjusted volumes performed most poorly in accounting for variance in memory scores. Hippocampal volumes adjusted by either measure of whole-brain volume performed equally well, although qualitative visual ratings of the hippocampus were at least as effective as the volumetric measures in predicting memory performance in community-dwelling individuals in the ninth or tenth decade of life.
为校正个体头部大小差异对海马体积的影响，人们采用了多种不同方法。此前研究人员使用定性视觉检查来评估海马萎缩情况。本研究的目的是确定在102名80岁以上社区居住个体中，预测记忆功能的最佳海马大小测量方法。使用磁共振成像（MRI）容积测定法和定性视觉评估来估计海马大小。通过三种不同的头部大小估计值对左右海马体积进行调整：总颅内体积（TICV）、包括脑室的全脑体积（WB+V）以及去除脑室后的全脑体积更精确测量值（WB）。我们使用线性回归比较了这三种容积调整方法和海马大小视觉评分在预测记忆表现方面的相对效果。所有四种海马大小测量方法都是记忆表现的显著预测指标。TICV调整后的体积在解释记忆分数方差方面表现最差。通过全脑体积的任何一种测量方法调整后的海马体积表现相当，尽管在预测九旬或十旬社区居住个体的记忆表现时，海马的定性视觉评分至少与容积测量方法一样有效。
