Li Y, Li J, Segal S, Wegiel J, De Santi S, Zhan J, de Leon M J
Department of Psychiatry, New York University School of Medicine, New York, NY 10016, USA.
AJNR Am J Neuroradiol. 2006 Apr;27(4):912-8.
Perihippocampal fissures (PHFs) and hippocampal sulcus residual cavities (HSCs) are common findings in the MR imaging examination of the hippocampus in aging and Alzheimer disease (AD); however, little is known about how to distinguish them or their relative clinical relevance. We hypothesized that prominence of the HSC, unlike PHF, is not significantly influenced by the hippocampal atrophy related to aging or AD.
We studied and evaluated these hippocampal CSF spaces on MR imaging scans from 130 normal control (NC) subjects (20-90 years of age) and 27 AD patients.
HSC is poorly correlated with age and is not related to the magnitude of hippocampal atrophy. There is no significant difference of HSCs between AD and age-matched NCs, but in the extremely high HSCs group (top 20%), 91% of cases are NC. PHFs, on the other hand, are strongly correlated with age and are valuable in the diagnosis of AD. Location and communication with ambient cistern is the key to distinguish HSC from PHF.
Identifying hippocampal atrophy (enlarged PHF) may be particularly challenging in the presence of HSC. Distinguishing among the CSF spaces in hippocampus may help in the radiologic evaluation of hippocampal atrophy. Patients with extremely high HSCs (>8.4) can be excluded from AD risk with 93% specificity.
海马旁裂（PHF）和海马沟残余腔（HSC）是衰老和阿尔茨海默病（AD）患者海马磁共振成像检查中的常见表现；然而，对于如何区分它们或它们的相对临床相关性知之甚少。我们推测，与PHF不同，HSC的突出程度不受衰老或AD相关的海马萎缩的显著影响。
我们对130名正常对照（NC）受试者（20 - 90岁）和27名AD患者的磁共振成像扫描中的这些海马脑脊液间隙进行了研究和评估。
HSC与年龄相关性差，且与海马萎缩程度无关。AD患者与年龄匹配的NCs之间的HSC无显著差异，但在极高HSC组（前20%）中，91%的病例为NC。另一方面，PHF与年龄密切相关，对AD诊断有价值。位置以及与环池的连通情况是区分HSC与PHF的关键。
在存在HSC的情况下，识别海马萎缩（扩大的PHF）可能特别具有挑战性。区分海马中的脑脊液间隙可能有助于对海马萎缩进行影像学评估。HSC极高（>8.4）的患者可以以93%的特异性被排除AD风险。
