A preliminary study of the biochemical environment of infertile testes with clinical varicocele

Seminal TEX101 May Predict Seminal Sperm Recovery after Varicocelectomy in Nonobstructive Azoospermic Patients with Varicocele

Background. Infertile men with nonobstructive azoospermia (NOA) associated with varicocele may benefit from varicocele repair with recovered sperms in semen. Currently, there is no clinically applied method to predict the success of seminal sperm recovery in this subset of azoospermic men. Objective. We aimed to evaluate the predictive role of the seminal testis expressed protein (TEX101) in sperm recovery in the semen of NOA men with palpable bilateral varicocele after microsurgical varicocelectomy. Patients and Methods. This prospective cross-sectional cohort study included 40 patients with NOA and bilateral varicocele. Seminal TEX101 levels were measured followed by subinguinal microsurgical varicocele repair. Two seminal analyses were carried out at 3- and 6-month follow-up periods to evaluate seminal sperm recovery. Results. After varicocele repair, sperms were recovered in the semen of 10/40 patients (25%) along the follow-up periods (seven patients after 3 months and additional three patients after 6 months). The preoperative median seminal TEX101 level was significantly higher in NOA men with seminal sperm recovery compared with NOA patients without seminal sperm recovery (13.5 vs. 9.8 ng/ml, $p=0.014$ ). Besides, the serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) median levels were significantly higher in NOA men without seminal sperm recovery compared with NOA men with seminal sperm recovery ( $p=0.001$ , $p=0.01$ ). There were nonsignificant differences comparing the preoperative testicular volume or serum testosterone levels between the two investigated groups ( $p=0.072$ , $p=0.272$ ). A cutoff value of 9.9 ng/ml was demonstrated to have preoperative TEX101 prediction of seminal sperm recovery (sensitivity of 90% and specificity of 57%). Conclusion. Preoperative seminal TEX101 could be considered as a biomarker for sperm recovery for seminal sperm recovery in NOA cases associated with varicocele after its surgical repair. Further work at this point with larger number of cases should be carried out to verify its potential importance.

Diffusion-weighted magnetic resonance imaging and magnetic resonance spectroscopy for non-invasive characterization of azoospermia: A prospective comparative single-center study

BACKGROUND

Azoospermia affects about 15% of childless males. The differential diagnosis between subtypes of azoospermia is the initial step in its management.

OBJECTIVES

To investigate the role of diffusion-weighted magnetic resonance imaging and proton magnetic resonance spectroscopy in distinguishing obstructive azoospermia from non-obstructive azoospermia and predicting sperm retrieval together with histological alterations in men with non-obstructive azoospermia.

MATERIALS AND METHODS

This prospective comparative study involved 60 men with obstructive azoospermia (group A) and 60 men with non-obstructive azoospermia (group B). Scrotal proton magnetic resonance spectroscopy and diffusion-weighted magnetic resonance imaging were conducted for all participants to respectively evaluate testicular metabolites and normalized apparent diffusion coefficient 1 week before sperm retrieval.

RESULTS

Apparent diffusion coefficient was significantly higher in group B as compared to group A (0.47 ± 0.11 vs. 0.29 ± 0.05; and 0.46 ± 0.14 vs. 0.28 ± 0.02) for the right and left testis, respectively. Conversely, testicular choline and lipids were significantly higher in group A as compared to group B. Normalized apparent diffusion coefficient, choline, and lipids at cut-off levels of 0.353, 0.31, and 0.725 could differentiate between obstructive azoospermia and non-obstructive azoospermia (area under the curve = 0.963; confidence interval = 0.939-0.986, area under the curve = 0.985; confidence interval = 0.974-0.997, and area under the curve = 0.970; confidence interval = 0.940-0.999, respectively). Regarding the prediction of sperm retrieval in the non-obstructive azoospermia group, choline levels had the highest area under the curve (0.923), and its cut-off level was 0.195. The normalized apparent diffusion coefficient was significantly lower in men with positive sperm retrieval as compared to men with unsuccessful retrieval. Finally, it was revealed that all magnetic resonance imaging parameters except creatine could independently predict testicular histology in men with non-obstructive azoospermia. The highest prediction was 95% in normal spermatogenesis, and the least prediction was 40% in spermatid arrest. Regression analysis was used to detect final predictors and extrapolate an equation that could be used to predict testicular pathology CONCLUSIONS: Normalized apparent diffusion coefficient and proton magnetic resonance spectroscopy are helpful in differentiating obstructive azoospermia from non-obstructive azoospermia and predicting sperm retrieval and related histological alterations in men with non-obstructive azoospermia.

Dynamic contrast-enhanced MRI in the assessment of testicular perfusion in infertile men with clinical varicocele

BACKGROUND

Varicocele represents the most common correctable cause of male infertility. The presence of non-invasive imaging parameters providing evidence as to which patients with varicocele are at risk for infertility would be important.

PURPOSE

To explore the role of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) using semi-quantitative parameters in the assessment of testicular perfusion in infertile men with clinical varicocele.

MATERIAL AND METHODS

The study cohort included 11 infertile men with clinical varicocele and six controls, with prior paternity. Subtraction DCE-MRI was performed after gadolinium administration, using a three-dimensional fast field-echo sequence. Time-signal intensity curves were created and semi-quantitative parameters were calculated. The independent samples t-test was used to compare basic T1 perfusion parameters between infertile testes with clinical varicocele and normal testes. Logistic regression analysis was performed to assess the most significant predictor of the diagnosis of clinical varicocele.

RESULTS

Both testes with clinical varicocele and normal testes enhanced moderately and homogeneously, with a linear increase of enhancement throughout the examination. Higher mean values of maximum enhancement (P = 0.026), maximum relative enhancement (P = 0.024), and wash-in rate (P = 0.013) were detected in the testes of infertile men with clinical varicocele, compared to the normal population. The wash-in rate proved the most significant predictor of the diagnosis of clinical varicocele (P = 0.013).

CONCLUSION

DCE-MRI may provide a valuable insight into the testicular perfusion of infertile men with clinical varicocele. The wash-in rate proved a strong and independent predictor of the diagnosis of clinical varicocele.

Varicocele associated male infertility: cellular and molecular perspectives of pathophysiology

BACKGROUND

Varicocele is a common risk factor associated with reduced male fertility potential. The current understanding of varicocele pathophysiology does not completely explain the clinical manifestation of infertility. The present treatment options such as antioxidant supplementation and varicocelectomy only helps ∼35% of men to achieve spontaneous pregnancy.

OBJECTIVE

This review aims to summarize the available knowledge on cellular and molecular alterations implicated to varicocele associated male infertility and also highlights the new knowledge generated by 'Omics' technologies.

MATERIALS AND METHODS

PubMed, MEDLINE, Cochrane and Google Scholar databases are searched using different combinations of keywords (varicocele, infertile/fertile men with varicocele, cellular changes, molecular mechanisms, proteome, epigenome, transcriptome and metabolome). A total of 229 relevant human and animal studies published till 2021 were included in this review.

RESULTS

Current understanding advocates oxidative stress (OS) as a major contributory factor to the varicocele associated male infertility. Excessive OS causes alteration in testicular microenvironment and sperm DNA fragmentation which further contributes to infertility. Molecular and omics studies have identified several promising biomarkers such as AAMP, SPINT1, MKI67 (genetic markers), sperm quality and function related protein markers, global sperm DNA methylation level (epigenetic marker), Hspa2, Protamine, Gadd7, Dynlt1 and Beclin1 (mRNA markers), PRDX2, HSPA, APOA2, YKL40 (seminal protein markers), total choline and PHGDH (metabolic markers).

DISCUSSION

Mature spermatozoa harbours a plethora of molecular information in form of proteome, epigenome and transcriptome; which could provide very important clues regarding pathophysiology of varicocele associated infertility. Recent molecular and omics studies in infertile men with varicocele have identified several promising biomarkers. Upon further validation with larger and well-defined studies, some of these biomarkers could aid in varicocele management.

CONCLUSION

The present evidences suggest inclusion of OS and sperm DNA fragmentation tests could be useful to the diagnostic workup for men with varicocele. Furthermore, including precise molecular markers may assist in diagnostics and prognostics of varicocele associated male infertility. This article is protected by copyright. All rights reserved.

When to ask for an MRI of the scrotum

Background

Multiparametric MRI (mpMRI) of the scrotum has been established as a useful second‐line diagnostic tool for the investigation of scrotal diseases. Recently, recommendations on clinical indications for scrotal MRI were issued by the Scrotal and Penile Imaging Working Group of the European Society of Urogenital Radiology.

Objective

To update current research on when to ask for an MRI of the scrotum.

Methods

PubMed database was searched for original articles and reviews published during 2010–2021.

Results

Eighty‐three articles fulfilled the search criteria. Scrotal MRI is mainly recommended after inconclusive US findings or inconsistent with the clinical examination and should be asked in the following cases: differentiation between intratesticular and paratesticular lesions (in rare cases of uncertain US findings), characterization of paratesticular and intratesticular lesions (when US findings are indeterminate), discrimination between germ cell and sex cord‐stromal testicular tumors, local staging of testicular malignancies (in patients planned for testis‐sparing surgery), differentiation between seminomas and non‐seminomatous tumors (when immediate chemotherapy is planned and orchiectomy is delayed), assessment of acute scrotum and scrotal trauma (rarely needed, in cases of non‐diagnostic US findings) and detection and localization of undescended testes (in cases of inconlusive US findings). Although preliminary data show promising results in the evaluation of male infertility, no established role for mpMRI still exists.

Conclusion

Multiparametric MRI of the scrotum, by assessing morphologic and functional data represents a valuable problem‐solving tool, helping to improve our understanding on the nature of scrotal pathology and the process of spermatogenesis. The technique may improve patient care and reduce the number of unnecessary surgical procedures.

Proton MR Spectroscopy in Assessing the Biochemical Milieu of Human Testes

Proton magnetic resonance spectroscopy (MRS), considered a connection between metabolism and anatomic and functional information provided by standard MRI, gives information on various tissue metabolites and their pathologic changes. Recently, proton MRS has been added as an adjunct tool to the multiparametric protocol of scrotal MRI, providing a new insight into the extremely complex biochemical milieu of normal and abnormal testes. This article reviews proton MR spectra of normal testes, showing age and bilateralism dependence. Disturbances of various metabolic pathways in testes of infertile men resulting in alterations of metabolite peaks are discussed. Preliminary data on proton MR spectra of testicular mass lesions are presented. LEVEL OF EVIDENCE: 5. TECHNICAL EFFICACY STAGE: 5.