Peak retrograde flow can serve as a valuable tool in predicting persistent, progressive and new onset asymmetry. Varicoceles associated with a peak retrograde flow of 38 cm per second or greater and 20% or greater asymmetry should be considered for varicocelectomy at initial presentation. Patients with peak retrograde flow greater than 30 cm per second need to be monitored carefully. Those with peak retrograde flow less than 30 cm per second are less likely to require surgery.

SSD is an easily measured parameter on NCCT that independently correlates with SWL efficacy in treating stones in all locations.

Asymmetry can be a transient phenomenon. Patients with initial asymmetry can end up with significant asymmetry, and many with significant asymmetry can have catch-up growth. However, when patients have a peak retrograde flow of 38 cm per second or greater on duplex Doppler ultrasound in association with 20% or greater asymmetry spontaneous catch-up growth is unlikely to occur.