ETD

• Bähren’s Classification
• clinical success
• complications
• endovascular embolization
• recurrence
• technical success
• varicocele

Background and Objectives
Varicocele, defined as an abnormal dilation of the pampiniform plexus veins, is one of the most frequent and correctable causes of male infertility. Endovascular embolization has emerged as a minimally invasive and effective alternative to surgery, providing direct venographic visualization and selective occlusion of refluxing veins.
This multicenter study aimed to evaluate the technical efficacy, clinical outcomes, and safety profile of varicocele embolization in a large real-world cohort, and to identify potential predictors of treatment success and recurrence, including Bähren’s venous classification, treatment indication, and patient age.
Primary outcomes were technical success (complete venous occlusion), clinical success (improvement in symptoms and/or semen parameters), and complications (rate and severity according to CIRSE’s classification). Secondary outcomes included recurrence rates and correlations with anatomical, clinical, and demographic variables.
Materials and Methods
All patients who underwent percutaneous embolization for varicocele between 2019 and 2024 at the Interventional Radiology Units of Pisa University Hospital and San Donato Hospital in Arezzo were included in the demographic and descriptive analyses. For inferential analyses, cases with incomplete or missing data were excluded.
Clinical and procedural information was extracted from medical records and radiology reports, and follow-up data were supplemented by telephone interviews (response rate 56.9%).
Data was processed using Microsoft Excel (Microsoft Corp., USA) and analyzed with IBM SPSS Statistics (version 31.0.1.0; IBM Corp., USA). Descriptive statistics reported frequencies and means ± standard deviation (± SD). Inferential analyses used Pearson's chi-square test, Fisher's exact test, and the independent samples t-test. Pre- and post-procedure changes in sperm quality measures were assessed using the McNemar test. Statistical significance was set at p < 0.05.
Results
A total of 397 patients with varicocele were treated between 2019 and 2024. The median follow-up period ranged from 9 to 69 months.
Mean patient age was 29.0±9.19 years. The main indications for embolization were symptomatic varicocele (31.2%) and infertility (18.4%). Left-sided varicoceles predominated (91.7%). The most frequent structural variations were Bahren Type I (32.2%) and Type II (30.2%), while complex patterns (Types IV–V) were uncommon. Transbrachial access was predominantly used (66.8%).
The technical success rate was 93.7%. The overall clinical success rate was 79.2% (among interviewed patients). The recurrence rate of the patients who completed follow-up was 16.3%.
Embolization also proved effective in patients with post-surgical recurrence, achieving clinical success in 52% of this subgroup. This highlights the procedural advantage of embolization, which allows real-time venographic mapping and targeted occlusion of collateral branches that may escape surgical identification.
Inferential analyses showed no statistically significant association between clinical outcomes and treatment indication, Bahren’s pattern, or age at treatment (p>0.05 for all outcomes). However, the association between Bähren’s pattern and technical success approached statistical significance (χ² p = 0.06), suggesting a potential trend where increased complexity of vein structure may raise technical difficulty.
Complications occurred in 6.6% of procedures, mostly mild events (CIRSE grades I–III). The most frequent events were vein rupture with leakage of contrast (1.3%) and vasovagal reaction (1.3%); only one case of testicular infarction (0.3%) was reported. Complications tended to cluster in technically unsuccessful procedures (50% vs. 10.7% in successful cases), though the difference was not statistically significant (p = 0.65).
Discussion and Conclusions
This study confirms that endovascular embolization is a safe, effective, and reproducible treatment for varicocele, achieving high technical and clinical success rates with low recurrence and complication rates. The procedure offers clear advantages over surgical ligation, as it enables real-time vein imaging, mapping, and targeted blocking of collateral branches that may escape from surgical identification.
Although age and venous anatomy were not significant indicators of outcome in these patients, the hypothesis that earlier intervention leads to greater improvement in sperm quality measures, as suggested by surgical evidence, indicates the need for future embolization studies.
Overall, these findings consolidate the pivotal role of interventional radiology in the management of varicocele. Percutaneous embolization should be regarded as a first-line, minimally invasive treatment option for symptomatic varicocele, male infertility, and post-surgical recurrence, combining efficacy, safety, and durable clinical outcomes.