ACUTE TESTICULAR TORSION - COMPARISON OF UNENHANCED AND CONTRAST-ENHANCED POWER DOPPLER US, COLOR DOPPLER US, AND RADIONUCLIDE IMAGING

PURPOSE: To compare the usefulness of conventional color Doppler ultra sound (US), unenhanced and contrast material-enhanced power Doppler US , and radionuclide imaging in a model of acute testicular torsion. MAT ERIALS AND METHODS: Twenty rabbits underwent unilateral 360 degrees te stis torsion and contralateral orchiopexy. Gray-scale, color Doppler, and unenhanced and contrast-enhanced power Doppler US were performed 4 -6 hours later. The side of torsion was determined, and intratestis fl ow tvas graded. Within 2 hours of US, technetium-99m pertechnetate was intravenously administered, the rabbits were killed, and the testes e xcised for radionuclide imaging. RESULTS: Intratestis perfusion was de tected in 85% of torsed testes at US and radionuclide imaging. The sid e of torsion was correctly diagnosed in 25% of cases with radionuclide imaging and in 60% of cases with US. Power Doppler US demonstrated si gnificantly greater intratestis flow in pexed than in torsed testes. A lthough the numbers of correct diagnosis with the three US modalities were similar, flow grades within torsed and normal testes were signifi cantly different. CONCLUSION Perfusion to torsed and normal testes was demonstrated equally well with color Doppler US, power Doppler US, an d radionuclide imaging. Doppler US better depicted differences in intr atesticular flow between torsed and normal testes.