de Tommaso Marina, Losito Luciana, Difruscolo Olimpia, Libro Giuseppe, Guido Marco, Livrea Paolo
Department of Neurologic and Psychiatric Sciences, University of Bari, Bari, Italy.
Headache. 2005 Oct;45(9):1208-18. doi: 10.1111/j.1526-4610.2005.00244.x.
The aim of this study was to perform a topographic and dipolar analysis of nociceptive-evoked responses obtained by laser stimulus under basal conditions in a cohort of chronic migraine (CM) patients, compared with migraine without aura (MWA) patients and noncraniofacial pain controls.
An increased activation of cortical areas devoted to the emotional and attentive components of pain was previously found during the course of the migraine attack; it was more pronounced in patients reporting higher frequency of migraine.
Twenty-six outpatients were enrolled in the study; 16 fulfilled the criteria of CM, and 10 were affected by MWA. Fifteen noncraniofacial pain subjects were also selected. The pain stimulus was a CO2 laser pulses. The right-supraorbital zone was stimulated. Source localization analysis was performed on the most prominent laser-evoked potentials (LEPs) peak (P2) for each data set. The anatomical locations of the P2 sources were projected onto a standard normalized 3D MRI model.
The CM group differed significantly from both MWA patients and controls for the x coordinate and from controls for the z coordinates. The P2 dipole localized in the rostral cingulate cortex in CM patients, lying in a more posterior location within the anterior cingulate cortex (ACC) in both controls and MWA patients. The x coordinate of the P2 dipole, expressing the postero-anterior location, was significantly correlated with frequency of headache.
CM seems to be characterized by a distinctive pattern of cortical elaboration of pain, with a prevalent activation of the rostral portion of the ACC: our results suggest that this may be a predisposing factor to migraine chronicity.
本研究旨在对一组慢性偏头痛（CM）患者在基础条件下通过激光刺激获得的伤害性诱发反应进行地形学和偶极分析，并与无先兆偏头痛（MWA）患者及非颅面部疼痛对照组进行比较。
先前发现在偏头痛发作过程中，负责疼痛情绪和注意力成分的皮质区域激活增加；在报告偏头痛发作频率较高的患者中更为明显。
26名门诊患者纳入研究；16名符合CM标准，10名患有MWA。还选择了15名非颅面部疼痛受试者。疼痛刺激为二氧化碳激光脉冲。刺激右侧眶上区。对每个数据集最突出的激光诱发电位（LEP）峰值（P2）进行源定位分析。将P2源的解剖位置投影到标准归一化三维磁共振成像（MRI）模型上。
CM组在x坐标上与MWA患者和对照组均有显著差异，在z坐标上与对照组有显著差异。CM患者的P2偶极位于喙部扣带回皮质，而对照组和MWA患者的P2偶极位于前扣带回皮质（ACC）内更靠后的位置。表示前后位置的P2偶极x坐标与头痛频率显著相关。
CM似乎具有独特的疼痛皮质加工模式，ACC喙部普遍激活：我们的结果表明，这可能是偏头痛慢性化的一个 predisposing 因素。 （注：predisposing 原词未翻译准确，可能是“易感的”之类意思，这里保留英文是因为不太明确准确中文释义）
