Introduction: Varicocele severity has been associated with larger testicular vein size but the relationship to decreased fertility remains debatable. In clinical practice, largest vein diameter is used to screen for surgical intervention, yet more recent studies have found venous reflux patterns and total testicular volume (TTV) to be associated with total motile sperm count (TMSC). This study compares largest testicular vein size and arterial flow rates to identify patients at risk for reduced seminal parameters. Methods: We conducted a retrospective single institution chart review over 14 years of 487 Tanner V adolescents. 148 met inclusion criteria of palpable, non-operated left sided varicoceles who underwent at least one SA and color doppler ultrasonography. Abnormal TMSC was defined by WHO 2010 criteria. Descriptive statistics, ROC analysis, univariate and multivariate logistic regression were performed using SPSS. Results: Data on 148 Tanner V adolescent males with mean age 18.24 ± 1.38 years were evaluated. Median diameter of largest left testicular vein was 3.5 mm (IQR 3.1-4.6), median peak systolic velocity (PSV) of left testicular artery was 10.4 cm/s (IQR 9.1-12.5), median end diastolic velocity (EDV) of left testicular artery was 5.1 cm/s (IQR 4.3-5.9), median value of PSV/EDV was 2.1 (IQR 1.8-2.3) and median TMSC was 37.4 million sperm/ejaculate (IQR 15.8-84.2). On ROC analysis regarding prediction of abnormal TMSC ( < 9 million sperm/ejaculate), left testicular PSV was found to have the greatest AUC at 0.73 (95% CI 0.62-0.85) with Youden index analysis determining cutoff of 10.22 cm/s while largest vein diameter was found to have an AUC of 0.48. On univariate logistic regression, PSV < 10.22 cm/s resulted in a significantly greater likelihood of abnormal TMSC (OR: 5.51 [1.84-16.46], p = 0.002), which persisted on multivariate logistic regression with adjustment for age (OR: 5.49 [1.83-16.43], p = 0.002). Conclusions: Left testicular PSV was most significantly correlated to TMSC. PSV < 10.22 cm/s was predictive of an abnormal TMSC. No significant association was found between larger veins and greater risk for abnormal TMSC. When assessing varicocele, left testicular artery PSV may help stratify future fertility risk, allowing for improved surveillance regarding surgical intervention. SOURCE OF Funding: None.
