Abstract

Objective: To compare the predictive value of clinical varicocele grade, color Doppler ultrasonography (CDUS)–measured venous diameter and pathologically measured venous diameter in predicting postoperative semen parameter improvement after microsurgical varicocelectomy.

Materials and Methods: This retrospective observational study included patients who underwent unilateral subinguinal microsurgical varicocelectomy between January 2022 and June 2025. Preoperative CDUS venous diameters (at rest and during Valsalva), clinical varicocele grade, intraoperatively excised pathological venous diameters, and semen analysis parameters were recorded. Improvement after varicocelectomy was defined as a ≥10% increase in sperm concentration and/or progressive motility. Correlation analyses and univariate and multivariate logistic regression models were used to identify predictors of postoperative improvement.

Results: A total of 55 patients were analyzed, of whom 44 (80.0%) demonstrated postoperative improvement in semen parameters. Pathological venous diameter was significantly larger in the improved group compared with the non-improved group (3.30 vs. 2.98 mm, p = 0.026). Pathological venous diameter showed a significant positive correlation with clinical grade (r = 0.307, p = 0.023), but not with CDUS-measured venous diameters. In multivariate analysis, higher clinical grade (Grade 2: OR = 4.523; Grade 3: OR = 6.544), larger pathological venous diameter (OR = 2.149), and lower preoperative sperm concentration (OR = 0.928) were independent predictors of postoperative semen improvement. CDUS-derived venous diameters were not predictive.

Conclusion: Pathological venous diameter and clinical varicocele grade appear to be more informative than CDUS-measured venous diameter in predicting semen parameter improvement after varicocelectomy. These findings suggest that the anatomical extent of venous dilation may better reflect the potential reversibility of varicocele-related testicular dysfunction.

Introduction

Varicocele, defined as the dilation and reflux of the pampiniform plexus veins, represents the most common and surgically correctable cause of male infertility [1]. It is identified in approximately 15% of men with primary infertility and up to 80% of those with secondary infertility [2]. The detrimental effects of varicocele on spermatogenesis have long been recognized, with several pathophysiological mechanisms, such as testicular hyperthermia, increased oxidative stress, hormonal dysfunction, and venous stasis, proposed to underlie impaired testicular function [3].

Although physical examination remains the cornerstone of diagnosis, its observer-dependent nature limits diagnostic accuracy [4]. Therefore, scrotal color Doppler ultrasonography (CDUS) has become a widely accepted complementary tool for confirming varicocele and assessing its severity [5]. Scrotal color Doppler ultrasonography provides an objective and quantitative assessment that supports clinical examination, as emphasized in previous reports [6]. In routine practice, a venous diameter >3 mm and reflux lasting longer than 2 seconds during the Valsalva maneuver are commonly regarded as diagnostic thresholds for clinical varicocele [7,8]. Furthermore, Schiff et al. reported in 2006 that patients with a venous diameter ≥3 mm accompanied by Valsalva-induced reflux experienced significant postoperative improvements in sperm count and motility [9].

However, the extent to which ultrasonographically measured venous diameters correspond to the actual macroscopic and morphological characteristics of dilated veins removed during surgery remains insufficiently investigated [10,11]. Only one study to date has shown that intraoperative venous diameters are systematically underestimated by preoperative CDUS [12]. The relationship between surgically measured venous size and postoperative semen improvement, or broader clinical infertility outcomes, thus remains unclear, representing a notable gap in the literature.

Our study aims to address this gap by evaluating the correlation between preoperative CDUS findings and intraoperative venous measurements, as well as exploring the association between surgically measured venous dimensions and postoperative semen parameters.

Materials and Methods

This retrospective observational study was conducted by reviewing the medical records of patients who underwent microsurgical varicocelectomy between January 2022 and June 2025. Ethical approval was obtained from the institutional review board on 17 July 2025 (Protocol No. 12/23). No additional interventions were performed, and all data were extracted from the hospital"s electronic medical record system.

A priori sample size calculation was performed based on the primary objective of assessing the association between two continuous variables (ultrasonographic vein diameter and surgically measured vein diameter) using correlation analysis. Using G*Power version 3.1, and assuming a moderate effect size (r = 0.40), a two-sided alpha level of 0.05, and 80% power (1–β = 0.80), the minimum required sample size was calculated as 47 patients. In addition, for the secondary outcome evaluating postoperative semen improvement, defined as a ≥10% increase in sperm concentration and/or progressive motility, an a priori sample size calculation was also performed. The calculation was based on a within-patient pre–post comparison of continuous semen parameters underlying this improvement definition. Assuming a moderate standardized effect size (Cohen"s d = 0.40), a two-sided alpha level of 0.05, and 80% power (1–β = 0.80), a minimum sample size of approximately 50 patients was required.

A total of 55 patients aged 18–45 years who had a CDUS and underwent unilateral subinguinal microsurgical varicocelectomy were included. Exclusion criteria were: (i) previous scrotal surgery, (ii) bilateral varicocelectomy, (iii) missing or incomplete CDUS data, and (iv) incomplete follow-up records.

Preoperative CDUS data were obtained from archived radiology reports. All examinations were performed with the patient in the standing position, both at rest and during the Valsalva maneuver. For each patient, the maximum venous diameter measured at rest and during Valsalva was recorded.

During surgery, the dilated pampiniform plexus veins were excised and appropriately submitted to the pathology department. In the pathology unit, all venous segments were measured in millimeters, and the largest venous diameter for each patient was recorded.

Demographic characteristics [age, body mass index (BMI)], clinical parameters (presence of testicular atrophy, clinical grade), semen analysis results (concentration, progressive motility, morphology), preoperative CDUS venous diameters, and pathological venous diameters were evaluated. Testicular atrophy was determined based on CDUS-measured testicular volumes. Postoperative semen parameters were derived from sperm analysis performed at 6 months. Testicular volumes were calculated using the Lambert formula, and a reduction of more than 20% in the volume of the affected testis compared with the contralateral testis was considered indicative of testicular atrophy.

Previous studies have demonstrated that varicocelectomy typically results in an average improvement of approximately 9–10% in sperm concentration or progressive motility, a change considered clinically meaningful [13]. Therefore, improvement after varicocelectomy was defined as a ≥10% increase in sperm concentration and/or progressive motility in the postoperative semen analysis.

Statistical Analysis
Statistical analyses were performed using IBM SPSS Statistics version 25.0. Normality of continuous variables was assessed using the Kolmogorov–Smirnov and Shapiro–Wilk tests. Continuous variables were expressed as mean ± SD or median (IQR), and categorical variables as frequencies and percentages. Correlations between pathological vein diameter and clinical/imaging variables were evaluated using Pearson or Spearman correlation analyses according to data distribution. To identify factors predicting postoperative improvement in semen parameters, a univariate logistic regression analysis was first conducted, and variables with a p value <0.20 were subsequently included in the multivariate logistic regression model. A twotailed p value <0.05 was considered statistically significant.

Results

The demographic, clinical, CDUS, and semen parameters of the entire cohort, along with the comparisons between patients with and without improvement in semen parameters, are presented in Table 1. The mean age was 30.09 ± 7.17 years and the median BMI was 23.80 (IQR: 5.10) kg/m². Testicular atrophy was present in 16.4% of the cohort. Clinical grading showed that 14.5% of patients were classified as Grade 1, 49.1% as Grade 2, and 36.4% as Grade 3. Preoperative CDUS revealed a median venous diameter of 3.00 mm (IQR: 1.30) at rest and 3.60 mm (IQR: 1.50) during the Valsalva maneuver. The median pathological venous diameter was 3.20 mm (IQR: 0.97).

Table 1. Demographic and clinical characteristics of the cohort

Postoperative semen analysis demonstrated overall improvement in sperm parameters. Median progressive sperm motility increased from 22.0% (IQR: 31.0) preoperatively to 36.0% (IQR: 32.0) postoperatively, and median sperm concentration increased from 4.00 (IQR: 7.80) million/mL to 8.00 (IQR: 21.80) million/mL. Sperm morphology did not show any significant change. Based on the study definition of benefit, an increase of at least 10% in sperm concentration and/or motility, 44 patients (80.0%) were categorized into the improved group, while 11 patients (20.0%) showed no meaningful improvement.

Comparison between the improved and non-improved groups revealed no significant differences in age, BMI, presence of testicular atrophy, CDUS-measured preoperative venous diameters, or preoperative semen parameters (all p> 0.05). However, pathological venous diameter was significantly larger in the improved group compared with the non-improved group (3.30 mm vs. 2.98 mm; p = 0.026). Clinical grade distribution also differed between the groups (p = 0.049), with Grade 3 varicocele being more frequent in the improved group and Grade 1 more common in the non-improved group.

The correlation analysis examining the relationship between pathological venous diameter and preoperative CDUSmeasured venous diameters at rest and during the Valsalva maneuver, as well as clinical varicocele grade, is presented in Table 2. Correlation analysis demonstrated that pathological venous diameter had a significant positive correlation with clinical grade (r = 0.307; 95% CI: 0.037–0.535; p = 0.023). In contrast, no statistically significant correlation was observed between pathological venous diameter and ultrasonographically measured venous diameters, either at rest (r = 0.255; p = 0.060) or during the Valsalva maneuver (r = 0.247; p = 0.069).

Table 2. Correlation analysis between pathological venous diameter and clinical grade, preoperative resting vein diameter, and Valsalva vein diameter

The logistic regression analysis performed to identify independent predictors of improvement in semen parameters is presented in Table 3. Multivariate results showed that higher clinical grade was independently associated with a greater likelihood of postoperative improvement (Grade 2: OR = 4.523, p = 0.018; Grade 3: OR = 6.544, p = 0.031). Lower preoperative sperm concentration also predicted improvement (OR = 0.928; p = 0.048). Additionally, pathological venous diameter emerged as an independent predictor of postoperative benefit (OR = 2.149; p = 0.049). No significant associations were found for age, BMI, testicular atrophy, preoperative venous diameters, motility, or morphology.

Table 3. Univariate and multivariate logistic regression analysis for predictors of improvement after varicocelectomy

Discussion

In this study, we investigated the relationship between preoperative CDUS findings, surgically excised venous dimensions, and postoperative semen outcomes in patients undergoing microsurgical varicocelectomy. The key finding of our analysis is that the pathological venous diameter, rather than the CDUS-measured vein diameter, demonstrated a significant association with both clinical varicocele grade and postoperative improvement in semen parameters. Although CDUS remains a widely used diagnostic tool, its measurements showed no significant correlation with the actual venous size determined by pathology. Importantly, clinical grade, larger pathological venous diameter, and lower preoperative sperm concentration emerged as independent predictors of postoperative improvement.

Color Doppler ultrasonography is widely used as a complementary tool in varicocele evaluation, yet previous evidence shows that both its diagnostic performance and its ability to predict varicocelectomy outcomes remain inconsistent. Cocuzza et al. demonstrated that the diagnostic accuracy of physical examination varies significantly according to examiner experience, while CDUS provides a more objective and standardized assessment that improves interobserver agreement compared with physical examination alone [11]. However, Wosnitzer et al. reported that preoperative ultrasound measurements systematically underestimate venous diameter relative to intraoperative findings, indicating a structural discrepancy between sonographic appearance and true anatomic vein size [12]. Regarding postoperative semen improvement, Schiff et al. showed that men with a venous diameter ≥3 mm accompanied by Valsalva-induced reflux experienced significantly greater gains in sperm concentration and motility following varicocelectomy [9]. In contrast, Babai et al. found that CDUS-detected reflux had no measurable effect on baseline semen parameters and did not predict postoperative improvement [14]. In the present study results also indicate that CDUS-derived venous measurements alone do not reliably reflect the true venous anatomy and are limited in predicting varicocelectomy success. Instead, pathologically measured venous diameter, together with clinical varicocele grade emerged as the parameters most closely associated with postoperative semen improvement, suggesting that true anatomic dilatation may better capture the reversible pathophysiological burden of varicocele.

Because pathological venous diameter is obtained intraoperatively and confirmed postoperatively, it cannot be used for preoperative patient evaluation, surgical indication, or decision-making. Therefore, its clinical utility differs fundamentally from that of clinical varicocele grade and preoperative CDUS parameters. Nevertheless, pathological vein diameter appears to reflect the true anatomic severity of venous dilatation more accurately than ultrasonographic measurements and may be more closely associated with the reversibility of varicocele-related testicular dysfunction. From a practical perspective, this finding mainly informs postoperative patient counselling, as larger excised venous diameters are associated with a higher likelihood of meaningful improvement in semen parameters. Indirectly, it also reinforces the importance of careful physical examination and clinical grading over sole reliance on CDUS-derived vein diameter in routine clinical practice.

The lack of correlation between CDUS-measured venous diameters and pathological vein size in our study can be explained by several technical and physiological factors known to affect ultrasonographic assessment. Venous measurements on CDUS are influenced by probe pressure, patient position, and dynamic venous distension, which can lead to systematic underestimation [12]. The finding that pathological venous diameter correlates with postoperative semen improvement may reflect the greater reversibility of advanced venous congestion: larger varicoceles are associated with more pronounced testicular hyperthermia, oxidative stress, and impaired spermatogenesis [3,15,16]. Thus, once abnormal venous drainage is corrected surgically, men with more severe underlying venous dilation may experience greater functional recovery. The independent predictive value of higher clinical grade is aligned with this interpretation, as clinical grading reflects the degree of venous dilation and reflux. Furthermore, the association between lower preoperative sperm concentration and greater postoperative improvement is consistent with prior evidence showing that men with more severely impaired baseline semen parameters often exhibit the most measurable postoperative gains following varicocelectomy [13].

A major strength of this study is that it directly compares preoperative CDUS findings with pathologically measured venous diameters, a relationship that has received limited attention in the literature. The use of homogeneous surgical technique performed by a single experienced microsurgeon minimizes procedural variability and enhances internal validity. Additionally, the integration of imaging, clinical, pathological, and postoperative semen parameters provides a comprehensive assessment of factors influencing reproductive outcomes after varicocelectomy.

However, several limitations must be acknowledged. The retrospective design introduces inherent risks of missing data and potential selection bias. Pathological venous measurements may be influenced by tissue handling and formalin fixation, which can introduce minor variations compared with in vivo anatomy. Semen analysis results are subject to natural intra-individual variability, and multiple ejaculates were not consistently available for all patients. Additionally, although semen improvement was assessed, patients" actual fertility outcomes were not evaluated, representing an important limitation. Furthermore, because this was a single-center study with a relatively modest sample size, the generalizability of the findings may be restricted. Prospective multicenter studies with standardized intraoperative venous measurements are needed to validate these observations and to better define the prognostic value of actual venous morphology in predicting postoperative reproductive outcomes.

Conclusion

In conclusion, pathological venous diameter emerged as a significant predictor of postoperative improvement in semen parameters, whereas CDUS-measured vein diameters showed no meaningful correlation with either actual venous anatomy or reproductive outcomes. Clinical grade and lower preoperative sperm concentration were also independently associated with greater postoperative benefit. These findings suggest that the true structural severity of venous dilation, better reflected by pathological measurement than by ultrasonography, may play a more decisive role in the reversibility of varicocele-related testicular dysfunction. Further prospective studies incorporating standardized intraoperative measurements are warranted to validate these results and refine prognostic assessment in men undergoing varicocelectomy.

Ethics Committee Approval: Ethical approval was obtained from the Ethics Committee of Antalya Training and Research Hospital on 17 July 2025 (Protocol No. 12/23).

Informed Consent: An informed consent was obtained from all the patients.

Publication: The results of the study were not published in full or in part in form of abstracts.

Peer-review: Externally peer-reviewed.

Authorship Contributions: Any contribution was not made by any individual not listed as an author. Concept – M.Ş., Ç.Ö., S.T.; Design – M.Ş., Ç.Ö., S.T., M.R.İ., S.Ü.C.; Supervision – S.T.; Resources – M.Ş., S.T., S.Ü.C.; Materials – M.Ş., Ç.Ö.; Data Collection and/or Processing – Ç.Ö., S.T., S.Ü.C.; Analysis and/or Interpretation – M.Ş., Ç.Ö., S.T.; Literature Search – S.T., M.R.İ., S.Ü.C.; Writing Manuscript – Ç.Ö., S.T., M.R.İ.; Critical Review – M.Ş., Ç.Ö., S.T.

Conflict of Interest: The authors declare that they have no conflicts of interest.

Financial Disclosure: The authors declare that this study received no financial support.

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