[Experimental studies on the rheologic behavior of blood in ultraviolet therapy]

The increased apparent blood viscosity proved in peripheral circulatory disease, the frequent failure of therapy by means of vasodilating medicaments and the successful therapy with the help of ultraviolet radiation of blood (UVB) by means of various techniques motivated investigations of the flow properties of blood with UVB. In six patients with angiologically ascertained arterial occlusive disease the flow properties of blood were investigated under standardized conditions by both viscosimetric techniques and independent of it by means of the centrifugation method. Plasma viscosity, apparent blood viscosity, parameters of aggregation and deformation of erythrocytes were determined before and after fictitious UVB on the hand one and before and after real UVB on the other hand. It was shown that within the limit of measurement accuracy there were no significant differences between fictitious and real UVB in plasma viscosities. Both the aggregation parameter of the centrifugation method and the apparent blood viscosity for low shear gradients before the 3rd UVB and all following ones differed significantly from those of the first UVB. No changes were found in the deformation parameters HCC infinity and the apparent viscosity for high shear gradients during UVB therapy. Possible mechanisms leading to the demonstrated improvements of the flow properties of blood by means of UVB are discussed.