Painful heating for evaluating trigeminal small nerve fiber function in patients with migraine / 中华物理医学与康复杂志

ABSTRACT

Objective To study any functional changes in the trigeminal nociceptive system in cases of migraine with aura (MWA) using painful heat-evoked potentials (CHEPs),and to explore the value of CHEP in evaluating the trigeminal small nerve fibers of patients with MWA.Methods Sixty patients with MWA were recruited as the MWA group,and 60 healthy persons were selected as a normal control group.Thermal stimulation at 51 ℃ was applied to the skin above the patients' right and left eyebrows.The N wave latencies and N-P amplitudes of the CHEPs were recorded at the vertex (Cz) of the head.The intensity of the stimulus was graded using a visual analogue scale (VAS).Results In the control group the simulation produced no significant differences in the N550 or P750 latencies or in the N-P amplitudes.In the MWA group no significant differences were observed when the headache side was stimulated,but the N550 and P750 latencies were both significantly shorter than those of the control group and the N-P amplitude was significantly greater than that of the control group.The average VAS score on both sides in the patients with migraine was significantly higher than those of the control group.However,there was no significant difference in average VAS scores between the headache and non-headache sides of the patients with migraine.Conclusions CHEP is a reliable method for detecting any pathological changes in the trigeminal small nerve sensory pathway.Increased cutaneous allodynia in acute migraine attacks is detectable using CHEPs.