Fig. 2

Increased synovial vascularity of joints of patients with hemophilic arthropathy on color Doppler ultrasound. a Eight-year old boy with severe hemophilia A and a history of prior bleeding into his right ankle. Mild hypervascularity is seen in his joint on color Doppler ultrasound. Color Doppler sonogram obtained on the sagittal anterior-lateral plane at the L2 level shows more than 4 color pixel dots encompassing less than 50% of the synovium extent within the color Doppler box which represents some degree of synovitis. Score equals 1. The area of color pixels within the color box is 4,257 units². b Twelve-year old boy with severe hemophilia A and a history of recurrent bleeding into his left elbow. Extensive hypervascularity is seen in his joint on color Doppler ultrasound. Color Doppler sonogram obtained on the sagittal anterior medial plane at the L1 level shows more than 4 color pixel dots encompassing 50% or more of the synovium extent within the color Doppler box. Score equals 2. The area of color pixels within the color box is 13,605 units²