The aim of this study was the determination of blood flow characteristics and parameters in the hand arteries of patients with primary Raynaud's phenomenon (pRP) and comparison with the results of healthy subjects. The diameter, resistive index and flow volume of the digital, ulnar and radial arteries of the patients with pRP and the control group were measured at rest and after cold provocation. The flow starting time (FST) in the digital artery and the flow normalising time (FNT) of all three arteries were also recorded after cold provocation. The diameter and flow volume of the digital and ulnar arteries of the patients were lower at rest, but resistive index was significantly high in all arteries. After cold provocation, the diameters of the radial and ulnar arteries and the flow volume of the digital arteries of the patients were significantly lower than those of the controls. The mean FST was 3.6 +/- 3.8 min for the patients and 0.9 +/- 1.2 min for the controls. The mean FNT was significantly longer in all the arteries of the patients; FNT cutoff times for the radial, ulnar and digital arteries were 6.5, 5.5 and 6.5 min, respectively. The measurements of the diameter, resistive index and flow volume of all the arteries measured before and after cold provocation as well as FST of the digital artery and FNT of all the arteries may facilitate in providing additional information in pRP patients.