Maton B M, Najm I M, Wang Y, Lüders H O, Ng T C
Section of Epilepsy, The Cleveland Clinic Foundation, OH 44195, USA.
Neurology. 1999 Dec 10;53(9):2045-52. doi: 10.1212/wnl.53.9.2045.
To determine the temporal and spatial extent of the lactate (Lact) changes as correlated with seizure characteristics and EEG changes in the rat kindling model.
Prior studies using MRS have detected cerebral Lact postictally in animal models of seizures and in patients with intractable focal epilepsy.
We performed MRS in sham control rats (n = 4) and in rats stimulated in the right hippocampus at two different stages of the kindling and at three time points after the seizures: <2 hours (n = 8 and 5, stage 0 and stage 5), 2 to 3 hours (n = 5 and 6), and >3 hours (n = 4 and 2). Lact/creatine (Cr) and N-acetylaspartate (NAA)/Cr ratios were measured in six contiguous voxels (three left, three right) covering the hippocampi, anterior and posterior regions, and compared with EEG and ictal behavior. Lact/Cr ratios were measured at a very low level in the sham control rats and in the >3-hour group.
In the <2-hour group, Lact/Cr increase was higher in stage-5 rats as compared with stage-0 rats (p = 0.001, unpaired t-test) and sham control rats when all the voxels were considered. Lact/Cr ratios were higher in the stimulated area as compared with all other brain areas in stage-0 rats (p = 0.05, paired t-test) but not in the stage-5 rats. Similar results with more inter-animal variability were measured in the 2- to 3-hour group. NAA/Cr ratios increased significantly after stage-0 kindling in the stimulated hippocampus but not after stage-5 kindling.
Postictal Lact increase as assayed by MRS correlates with EEG and behavioral seizures and suggests that it would be an additional noninvasive technique for seizure localization during the presurgical evaluation of patients with intractable focal epilepsy.
确定在大鼠点燃模型中，乳酸（Lact）变化的时空范围，并将其与癫痫发作特征及脑电图（EEG）变化相关联。
先前使用磁共振波谱（MRS）的研究已在癫痫动物模型和顽固性局灶性癫痫患者中检测到发作后脑乳酸。
我们对假手术对照大鼠（n = 4）以及在点燃的两个不同阶段刺激右侧海马体的大鼠进行了MRS检测，并在癫痫发作后的三个时间点进行测量：<2小时（n = 8和5，阶段0和阶段5）、2至3小时（n = 5和6）以及>3小时（n = 4和2）。在覆盖海马体、前后区域的六个连续体素（三个左侧，三个右侧）中测量乳酸/肌酸（Cr）和N-乙酰天门冬氨酸（NAA）/Cr比值，并与EEG和发作行为进行比较。在假手术对照大鼠和>3小时组中，乳酸/Cr比值测量值处于非常低的水平。
在<2小时组中，当考虑所有体素时，与阶段0大鼠相比，阶段5大鼠的乳酸/Cr增加更高（p = 0.001，非配对t检验），且高于假手术对照大鼠。在阶段0大鼠中，与所有其他脑区相比，受刺激区域的乳酸/Cr比值更高（p = 0.05，配对t检验），但在阶段5大鼠中并非如此。在2至3小时组中测量到了类似结果，但动物间变异性更大。在受刺激的海马体中，阶段0点燃后NAA/Cr比值显著增加，但阶段5点燃后未增加。
通过MRS检测到的发作后乳酸增加与EEG和行为性癫痫发作相关，这表明它将成为顽固性局灶性癫痫患者术前评估期间用于癫痫灶定位的一种额外的非侵入性技术。
