Perfusion Scintigraphy for the Evaluation of Patients with Raynaud's Phenomenon.

Raynaud's phenomenon (RP) is a functional vascular disorder, which can be defined as transient vasospasm of the peripheral arteries and arterioles in the affected areas exposed to the cold or other stress. The diagnosis of RP is mainly based on symptoms. Perfusion scintigraphy, with or without cold stimulation, can be used to evaluate RP. Studies with perfusion scintigraphy for RP have shown that patients with RP showed lower finger-to-palm ratio than patients without RP. Responses after cold stimulation were also different in patients with RP. Not only decreased perfusion or blood pool after cold stimulation but also paradoxically increased perfusion can be shown in patients with RP. Some studies have shown that primary and secondary RP can be differentiated by perfusion scintigraphy. Correlation between duration of disease and findings on perfusion scintigraphy was reported. Perfusion scintigraphy can show differences before and after treatment as well. However, the protocols for perfusion scintigraphy for PR vary among studies. The standard protocol of perfusion scintigraphy for RP should be established.