Richardson M P, Friston K J, Sisodiya S M, Koepp M J, Ashburner J, Free S L, Brooks D J, Duncan J S
Epilepsy Research Group, Institute of Neurology, London, UK.
Brain. 1997 Nov;120 ( Pt 11):1961-73. doi: 10.1093/brain/120.11.1961.
Using [11C]flumazenil-PET and statistical parametric mapping (SPM), we have shown recently that regions of increased and decreased benzodiazepine receptor density may be seen in patients with localization-related epilepsy due to malformations of cortical development. These abnormalities were seen both within and beyond lesions visually apparent on high-resolution MRI. We have also shown, using an interactive anatomical segmentation technique and volume-of-interest measurements, that subtle and unsuspected abnormalities of cortical grey matter volume were found in the same group of patients on high-resolution MRI, beyond the lesions visually apparent. In 10 patients with localization-related epilepsy and malformations of cortical development, we have now applied the automated and objective technique of SPM to the analysis of high-resolution structural MRI. Each individual patient was compared with 16 normal control subjects. We have then simultaneously compared the structural and functional data obtained for each individual patient with normal control high-resolution MRI and [11C]flumazenil-PET image using a novel technique. This comparison allowed the detection of functional abnormalities that were not accounted for by either visible or unsuspected structural abnormalities, in an automated and statistically rigorous manner. Five patients had abnormalities of cortical grey matter volume detected using SPM; only these five patients had been found abnormal using the previous volume-of-interest technique. Six of the 10 patients showed regions of cerebral cortex with disproportionate flumazenil binding compared with local grey matter volume. This included regions not found to have abnormal flumazenil binding on analysis of the PET data alone. Furthermore, regions found to have abnormal binding on examination of the PET data alone were, in some instances, shown to be accounted for by abnormalities of cortical grey matter volume. We conclude that the analysis of ligand PET data should always include a comparison with structural MRI; such comparisons are greatly facilitated by the novel approach described.
使用[11C]氟马西尼正电子发射断层扫描（PET）和统计参数映射（SPM），我们最近发现，在因皮质发育畸形导致的局灶性癫痫患者中，可能会出现苯二氮䓬受体密度增加和降低的区域。这些异常在高分辨率磁共振成像（MRI）上视觉可见的病变内外均有发现。我们还使用交互式解剖分割技术和感兴趣体积测量方法表明，在同一组患者的高分辨率MRI上，除了视觉上明显的病变外，还发现了皮质灰质体积的细微且未被怀疑的异常。在10例因皮质发育畸形导致局灶性癫痫的患者中，我们现在将SPM的自动化和客观技术应用于高分辨率结构MRI的分析。将每位患者与16名正常对照受试者进行比较。然后，我们使用一种新技术，将每位患者获得的结构和功能数据与正常对照高分辨率MRI和[11C]氟马西尼PET图像同时进行比较。这种比较能够以自动化且统计学严谨的方式检测出既不是由可见的也不是由未被怀疑的结构异常所解释的功能异常。使用SPM检测出5例患者存在皮质灰质体积异常；只有这5例患者使用先前的感兴趣体积技术被发现异常。10例患者中有6例显示大脑皮质区域的氟马西尼结合与局部灰质体积不成比例。这包括仅对PET数据进行分析时未发现有异常氟马西尼结合的区域。此外，仅对PET数据进行检查时发现有异常结合的区域，在某些情况下，显示是由皮质灰质体积异常所导致的。我们得出结论，配体PET数据的分析应始终包括与结构MRI的比较；本文所述的新方法极大地促进了这种比较。
