The purpose of this study was to investigate the effect of use of intr
avenous ultrasonographic contrast agent in the diagnosis of gonadal to
rsion in an animal model. After examination of perfusion of normal gon
ads in male and female dogs, torsion was produced and maintained mecha
nically. Presence and pattern of blood flow was then reassessed before
and after administration of varying doses of perfluorocarbon-filled m
icrosphere intravenous contrast agent. Modes of examination included g
ray scale, color flow, color power, and spectral analysis using a tran
sducer placed directly on the surgically exposed gonads. Although no e
nhancement was perceptible on gray scale images, color and spectral Do
ppler signals were significantly stronger after injection of contrast
agent in both normal and rotated gonads. Perfusion asymmetry was more
obvious. Some residual flow was seen in partially rotated testes, and
absence of flow was documented in both partially and fully rotated ova
ries. Use of intravenous contrast medium improves demonstration of alt
ered flow patterns in ischemic gonads, allowing more confident diagnos
is.