A new near-infrared spectroscopy parameter as marker for patients with migraine.

Due to the lack of markers for migraine, diagnosis relies entirely on symptomatology. The aim is to evaluate the utility of a new near-infrared spectroscopy parameter as potential marker for patients with episodic migraine with (MA+) and without aura (MA-) during the interictal period of migraine. We studied 10 patients with MA+ (age 39.5 ± 12.2 years) and 10 with MA- (age 40.3 ± 10.2 years), according to ICHD-II criteria 2004, during the interictal period of migraine and 15 age and sex matched healthy control subjects. The cases and controls were free from vascular risk factors and migraine prophylactic medications. At rest in all the participants, the time delay in millisecond (ms), between the R-wave of an electrocardiogram and the arterial pulse wave of cerebral microcirculation detected by transcranial near-infrared Spectroscopy (R-APWCMtd) on the frontal cortex of both side, was determined. The patients with migraine had a significantly longer R-APWCMtd than the control subjects: the patients with MA+: +38.3 ms, p < 0.0002; the patients with MA-: +34.7 ms, p < 0.0002, and there was no significant difference between MA+ and MA-, p = 0.71. We used receiver-operator characteristic (ROC) curve to assess the diagnostic potential of the R-APWCMtd measurement for diagnosis of migraine; we found an ROC area of 0.92, p < 0.0001, sensitivity 77.8 %, specificity 100 % and cutoff of 242 ms. Our study seems to indicate that the longer R-APWCMtd is independently associated with a diagnosis of migraine, and may be considered a new marker for migraine, especially in patients with MA+.