Oppenheim C, Dormont D, Biondi A, Lehéricy S, Hasboun D, Clémenceau S, Baulac M, Marsault C
Department of Neuroradiology, Groupe Hospitalier Pitié-Salpêtrière, Paris VI University, France.
AJNR Am J Neuroradiol. 1998 Mar;19(3):457-63.
The purpose of our study was to determine the significance of the loss of visualization of digitations in the hippocampal head on high-resolution fast spin-echo MR images in the diagnosis of mesial temporal sclerosis (MTS).
MR examinations of 193 patients with intractable epilepsy were evaluated retrospectively for atrophy and/or T2 signal changes of the hippocampi. On the basis of these two criteria, MTS was diagnosed in 63 hippocampi. Twenty-four patients had surgery, and MTS was confirmed in all cases. A control group included 60 hippocampi in patients with frontal seizures but no MR-detectable abnormalities. In a second step, visibility of digitations in the hippocampal head was evaluated in the two groups of subjects.
In the group of 63 hippocampi in which MTS was diagnosed, digitations were not visible in 51 cases, poorly visible in eight, and sharply visible in four. Twenty-two of 24 hippocampi in which MTS was confirmed histologically had no MR-visible digitations. In the control group, digitations were sharply visible in 55 cases and poorly visible in five. Statistical analysis showed a significant difference in the visualization of digitations between hippocampi with MTS and those in the control group.
With a sensitivity of 92% and a specificity of 100%, the finding of complete loss of digitations in the hippocampal head may be used as a major diagnostic criterion to establish the MR diagnosis of MTS. This morphologic sign may also be useful in the diagnosis of bilateral MTS or to validate the MR diagnosis of MTS when there is no obvious atrophy or changes in signal intensity.
我们研究的目的是确定在高分辨率快速自旋回波磁共振成像上海马头部指状突显示消失在颞叶内侧硬化（MTS）诊断中的意义。
回顾性评估193例难治性癫痫患者的磁共振检查，观察海马的萎缩和/或T2信号变化。基于这两个标准，63个海马被诊断为MTS。24例患者接受了手术，所有病例均确诊为MTS。对照组包括60个额叶癫痫患者的海马，磁共振检查未发现异常。第二步，评估两组受试者海马头部指状突的可见性。
在诊断为MTS的63个海马组中，51例指状突不可见，8例可见性差，4例清晰可见。经组织学证实为MTS的24个海马中，22个磁共振上未见指状突。在对照组中，55例指状突清晰可见，5例可见性差。统计分析显示，MTS海马与对照组海马在指状突显示方面存在显著差异。
海马头部指状突完全消失这一发现，敏感性为92%，特异性为100%，可作为建立MTS磁共振诊断的主要诊断标准。这一形态学征象在双侧MTS的诊断中或在无明显萎缩或信号强度改变时验证MTS的磁共振诊断中也可能有用。
