For scrotal sonographic examination, Doppler ultrasound can be important for the assessment of varicoceles, for the diagnosis of testicular torsion, and for assessing testicular inflammation.
Doppler imaging before and during a Valsalva maneuver is used to diagnose the condition of varicocele. Color Doppler is used for the diagnosis of testicular torsion. Absence of flow on one side is proof of torsion. This is not as easy to perform using only gray-scale ultrasound.
Learn more about testicular ultrasonography.