The blood supply to fingers during Raynaud's attack: a comparison of laser-Doppler flowmetry with other techniques.

Responses to combined body and finger cooling were recorded by laser-Doppler flowmetry, Xenon-113 washout and strain-gauge plethysmography in 22 patients (seven patients with primary Raynaud's phenomenon (PR) and 15 with generalized scleroderma (GS] and nine healthy, warm-handed subjects. Finger systolic blood-pressure decreased to zero in 100% of the patients, after body and finger cooling as measured with strain-gauge plethysmography. With the laser-Doppler flowmeter a low-positive blood-pressure was registered in two patients. The duration of a Raynaud's attack was found to vary from 0.5 to greater than 5 minutes as observed by the laser-Doppler flowmeter. Xenon-133 washout from the fingertips, during a zero blood-flow situation, insignificantly deviated from the washout during vascular occlusion. It is concluded that; (1) the elicitation and duration of Raynaud's phenomenon could be clearly observed by laser-Doppler flowmetry; (2) the zero blood-flow observed by laser-Doppler flowmetry could be confirmed by Xenon-133 washout and (3) in GS cases, the laser-Doppler flowmetry seemed more sensitive than the strain-gauge, at extremely low blood flow values.