Small vessels with luminal diameters of 0.2-2.0 mm have not been studied with routine ultrasound diagnostic procedures. Modern color Doppler imaging technology, however, should allow visualization of the blood flow even in such small vessels. The present study was therefore aimed at demonstrating the possibilities of examining small arteries in the fingertips of healthy volunteers with color Doppler imaging. The question was whether or not a standardized visualization was possible. We found that small arteries and their blood flow could be demonstrated in all (n = 10) healthy subjects. Furthermore, we demonstrated pathologic findings in the fingertip arteries of a patient with thrombangitis obliterans as an example of the diagnostic value of these new procedures.