Free S L, Bergin P S, Fish D R, Cook M J, Shorvon S D, Stevens J M
Institute of Neurology, London, United Kingdom.
AJNR Am J Neuroradiol. 1995 Apr;16(4):637-43.
To investigate the use of six cerebral measures as correlates for hippocampal volumes and, therefore, to enable normalized absolute hippocampal volumes to be calculated via two correction processes.
Hippocampal volumes and six cerebral measures were estimated from MR data in 20 control subjects. Three of these measures (the cranial volume, the cerebral volume, and the midsagittal cranial area) were then applied to a group of 32 control subjects, and regression analysis was performed to investigate the linear relationship between hippocampal volume and each measure. Division of hippocampal volume by cerebral measure and correction via a covariance calculation enabled corrected absolute hippocampal volumes to be determined for 32 control subjects and 23 patients with temporal lobe epilepsy.
Correction processes reduced the variance in absolute hippocampal volumes in control subjects and enabled abnormally small absolute volumes to be defined. Of 11 patients with unilateral volume ratio abnormalities, 8 had unilateral abnormally small absolute hippocampal volumes. Of 12 patients with normal volume ratios, 4 had bilateral abnormally small absolute hippocampal volumes.
Correction processes can define absolute hippocampal volumes for correlation studies and may enable identification of unsuspected bilateral hippocampal volume loss.
研究六种脑测量指标作为海马体积相关因素的用途，从而通过两种校正方法计算标准化的绝对海马体积。
从20名对照受试者的磁共振数据中估计海马体积和六种脑测量指标。然后将其中三项测量指标（颅腔体积、脑体积和矢状中颅面积）应用于32名对照受试者，并进行回归分析以研究海马体积与每项测量指标之间的线性关系。通过将海马体积除以脑测量指标并通过协方差计算进行校正，可为32名对照受试者和23名颞叶癫痫患者确定校正后的绝对海马体积。
校正方法减少了对照受试者绝对海马体积的方差，并能够定义异常小的绝对体积。在11名单侧体积比异常的患者中，8例有单侧绝对海马体积异常小。在12例体积比正常的患者中，4例有双侧绝对海马体积异常小。
校正方法可为相关性研究定义绝对海马体积，并可能有助于识别未被怀疑的双侧海马体积丢失。
