[Finger plethysmography for studying the blood rheological and hemodynamic components of an acrosyndrome].

Digital plethysmography allows investigation of maximum digital pulse (M.D.P.) after immersion of hands at 45 degrees C over three minutes. It is correlated with digital arterial blood flow. Reactivity to cold is determined from the ratio M.D.P./digital pulse after local and body cooling over 3 minutes. Tests were performed on 65 controls, 69 patients with idiopathic Raynaud's syndrome, 12 with scleroderma, 10 with digital arteritis and 15 with Raynaud's phenomenon secondary to hemorheologic affections. Maximum digital pulse was significantly decreased in patients with digital arteritis and scleroderma. The M.D.P. was normal in controls and patients with idiopathic Raynaud's syndrome, and was significantly increased in patients with a rheologic Raynaud's phenomenon. Digital artery reactivity differentiates the populations studied: it was maximum in patients with scleroderma, moderate in controls and patients with isolated digital arteritis and marked in patients with idiopathic Raynaud's disease and those with rheologic Raynaud's phenomena.