Comparison among different methods for the diagnosis of varicocele. World Health Organization.

Three noninvasive methods for the detection of retrograde blood flow in the internal spermatic vein were evaluated in 141 men complaining of infertility in four different centers. Scrotal contact thermography using flexible strips was found to be the most accurate when compared with retrograde venography of the internal spermatic vein for a final diagnosis. Doppler sonography had a higher false-positive rate, while radionuclide angiography with static imaging had a higher false-negative rate. The combination of Doppler sonography and contact thermography resulted in the highest diagnostic accuracy, with only 1% false-negative results and 44% false-positive findings. The noninvasive methods revealed that 16% of patients investigated presented clinically undetectable reflux (subclinical varicocele). Because evidence presently available suggests that treatment of all degrees of varicocele may improve fertility, it is advised to use both scrotal thermography and Doppler sonography as part of the routine investigations of men consulting for infertility.