Cold-induced acral vasospasm in migraine as assessed by nailfold video-microscopy: prevalence and response to migraine prophylaxis.

In order to learn the prevalence of cold-induced vasospasm in migraine patients, blood cell velocity measurements of finger nailfold capillaries were performed in 58 consecutive patients suffering from migraine with and without aura. In 5 (8.6%) patients capillaroscopy could not be performed because of reduced nailfold transparency; 21 of the remaining 53 patients (39.6%) showed blood flow stop due to vasospasm under cold provocation. There was no significant difference (P = 0.69) in the occurrence of vasospastic reaction between migraine with (12 of 32 patients = 37.5%) and without (9 of 21 patients = 42.9%) aura. The clinical and capillaroscopic course under migraine prophylaxis was observed in 18 vasospastic patients. After sixteen weeks 14 patients showed good clinical improvement of their migraine. The vasospastic reaction persisted in only 1 patient. This patient and 3 others with abolished vasospasm were still suffering from migraine. These findings suggest that observing blood cell velocity noninvasively in nailfold capillaries under cold provocation could be useful for objectively monitoring the response to prophylactic treatment in migraine patients or for testing new potentially antimigraine drugs.