Laser Doppler flowmetry in subepidermal tumours and in normal skin of rats during localized ultrasound hyperthermia.

Laser Doppler flowmetry has been applied to normal skin and to subepidermal tumours during localized ultrasound hyperthermia in the rat. In normal skin, 40 degrees C hyperthermia only induced a marginal increase in the red blood cell flux. Significant increases occurred after 20 min at 42 degrees C and after 4 min at 44 degrees C. During 44 degrees C hyperthermia maximum fluxes were reached after 24 min. Thereafter, the flow declined and finally approached preheating values. In contrast, in subepidermal tumours 40 degrees C hyperthermia on the average induced a slight decrease of the flux. During 42 degrees C hyperthermia a significant flow decrease was found after 40 min of heating. Follow…