Resistance and pulsatility index increase in capsular branches of testicular artery: indicator of impaired testicular microcirculation in varicocele?

PURPOSE: To evaluate the effect of clinical varicocele on testicular microcirculation using spectral Doppler analysis.

METHODS

Forty-nine young and healthy volunteers were enrolled in this prospective study. Varicocele grades were determined according to sonographic parameters. Patients with left-sided clinical varicocele were classified as the patient group (n = 15), while the remaining patients served as controls (n = 34). Spectral Doppler measurements of testicular arteries (peak systolic/end diastolic velocity, resistance index, pulsatility index) were measured from capsular and intratesticular branches.

RESULTS

No statistically significant difference was found between the Doppler parameters obtained from the intratesticular branches of both testes and the capsular branches of the right testis. On the other hand, in left-sided clinical varicocele cases, the average resistance index (RI) and pulsatility index (PI) of capsular branches of the left testes (RI, 0.68 +/- 0.04; PI, 1.22 +/- 0.15) were significantly greater than in the control group (RI, 0.64 +/- 0.06; PI, 1.07 +/- 0.18) (p < 0.05 and p < 0.01, respectively).

CONCLUSIONS

Increased RI and PI of capsular branches of testicular arteries on spectral Doppler examination may be an indicator of impaired testicular microcirculation in patients with clinical varicocele. Further studies addressing the correlations with sperm counts are needed to determine the cut-off values for these indices.