FIRST-PASS RADIONUCLIDE ANGIOGRAPHY IN THE DIAGNOSIS OF AORTOILIAC THROMBOEMBOLISM IN A HORSE

First-pass radionuclide angiography of the terminal aorta was performe d in 3 normal horses and a 6-year-old Standardbred intact male with ao rtoiliac thromboembolism, Thromboembolism caused chronic bilateral hin d limb lameness, more severe in the right hind limb, was detected by r ectal examination, and confirmed using transrectal ultrasonography. Us ing Tc-99m-HDP, first-pass radionuclide angiography was combined with hind limb and pelvis hone (delayed) scintigraphy and revealed marked r eduction in blood flow through both external iliac arteries and absenc e of blood flow in the internal iliac arteries, Quantitative analysis showed a decreased activity in the right iliac vessels in the clinic p atient consistent with reduced blood flow when compared to control hor ses, First-pass radionuclide angiography provided a method to obtain d iagnostic images of the terminal aorta and branches and a method to di agnose aortoiliac thromboembolism in the horse.