['Our aim was to investigate effects of bosentan on hand perfusion in patients with systemic sclerosis (SSc) with pulmonary arterial hypertension (PAH), using laser Doppler perfusion imaging (LDPI).', 'We enrolled 30 SSc patients with PAH, 30 SSc patients without PAH, and 30 healthy controls. In SSc patients and healthy controls at baseline, skin blood flow of the dorsum of the hands was determined with a Lisca laser Doppler perfusion imager. The dorsal surface of the hands was divided into 3 regions of interest (ROI). ROI 1 included 3 fingers of the hand from the second to the fourth distally to the proximal interphalangeal finger joint. ROI 2 included the area between the proximal interphalangeal and the metacarpophalangeal joint. ROI 3 included only the dorsal surface of the hand without the fingers. LDPI was repeated in SSc patients and controls after 4, 8, and 16 weeks of treatment. In SSc patients, nailfold videocapillaroscopy and Raynaud Condition Score (RCS) were performed at baseline and at 4, 8, and 16 weeks.', 'SSc patients with PAH enrolled in the study received treatment with bosentan as standard care for PAH. In these patients with PAH, after 8 and 16 weeks of treatment, bosentan improved minimum, mean, and maximum perfusion and the perfusion proximal-distal gradient. Bosentan seems to be most effective in patients with the early and active capillaroscopic pattern than in patients with the late pattern. Bosentan improved skin blood flow principally in the ROI 1 compared to the ROI 2 and ROI 3. Bosentan restored the perfusion proximal-distal gradient in 57% of SSc patients with the early capillaroscopic pattern. No significant differences from baseline were observed in the RCS in SSc patients with PAH.'] Does bosentan improve skin perfusion of hands in patients with systemic sclerosis with pulmonary arterial hypertension?