SYSTEMIC-SCLEROSIS - BLOOD RHEOMETRY AND LASER-DOPPLER IMAGING OF DIGITAL CUTANEOUS MICROCIRCULATION DURING LOCAL COLD-EXPOSURE

A combined study of microcirculation hemodynamics in vivo and blood rh eometry has been carried out in patients with scleroderma compared to primary Raynaud's phenomenon (PRP) and healthy controls (HC). Laser Do ppler perfusion imaging was used to assess superficial skin blood flow in the fingers before, during and after local cold exposure. Blood vi scosity was measured at 19 and 37 degrees C. Dynamic and transient flo ws were also investigated. The scleroderma group showed a significantl y lower level of perfusion before the cold test, that was further decr eased during and after cold exposure, the difference with PRP being ma ximal during the rewarming period. It also showed a significantly incr eased viscosity (p < 0.05) at low shear rates. Hemorheological behavio r of the PRP group was similar to the HC group. A significant negative correlation between the LDI perfusion and the apparent blood viscosit y at low shear rates was found for the whole population. These finding s suggest that theological factors may be involved in the abnormal col d reactivity of patients with scleroderma.