The value of sonoelastography scores and the strain ratio in differential diagnosis of azoospermia

Elastography in the Urological Practice: Urinary and Male Genital Tract, Prostate Excluded—Review

The aim of this article is to review the utility of elastography in the day-to-day clinical practice of the urologist. An electronic database search was performed on PubMed and Cochrane Library with a date range between January 2000 and December 2021. The search yielded 94 articles that passed the inclusion and exclusion criteria. The articles were reviewed and discussed by organ, pathology and according to the physical principle underlying the elastographic method. Elastography was used in the study of normal organs, tumoral masses, chronic upper and lower urinary tract obstructive diseases, dysfunctions of the lower urinary tract and the male reproductive system, and as a pre- and post-treatment monitoring tool. Elastography has numerous applications in urology, but due to a lack of standardization in the methodology and equipment, further studies are required.

Experience of using shear wave elastography in evaluation of testicular stiffness in cases of male infertility

PURPOSE

The purpose of this study was to determine quantitative testicular tissue stiffness values in normal and infertile men using shear wave elastography (SWE), and to evaluate the relationship between infertility and testicular stiffness value.

METHODS

In total, 100 testes of 50 infertile patients with abnormal semen parameters were classified as group A, and 100 testes of 50 control subjects were classified as group B. These two groups were compared in terms of age, testicular volume, and SWE values. The group B testes were randomly chosen from patients who had applied for ultrasonography for any reason, and who had no testis disease and no history of infertility.

RESULTS

The mean age of the patients was 27.83 years, and no significant difference in age was found between the groups (P = 0.133). No significant difference in testicular volume was found between the groups (P = 0.672). The SWE values were significantly higher in group A than in group B (P = 0.000 for both m/s and kPa values). SWE values had a negative correlation with mean testicular volume in group A (for m/s values: P = 0.043; for kPa values: P = 0.024).

CONCLUSION

SWE can be a useful technique for assessing testicular stiffness in infertile patients to predict parenchymal damage in testicular tissue that leads to an abnormality in sperm quantity. In addition, decreased testicular volume, together with increased SWE values, can reflect the degree of parenchymal damage.

Evaluation of Normal and Varicocele-Bearing Testes Using Real-time Strain Elastography

OBJECTIVES

To evaluate testes in patients with varicocele using real-time strain elastography and to correlate the results with the patients' clinical, seminal, and hormonal profiles.

METHODS

Fifty patients with left varicocele and 20 age-matched control participants were included in the study. All participants were evaluated via a historical interview, clinical examination, including testicular volume and varicocele grade, hormonal assay (total and free testosterone, luteinizing hormone, and follicle-stimulating hormone), computer-assisted semen analysis, and testicular assessment using real-time strain elastography to define the strain ratio and elasticity score.

RESULTS

Testicular volume and sperm parameters were significantly lower (P < .001), whereas the follicle-stimulating hormone level, strain ratio, and elasticity score were significantly higher (P < .01; P < .001; P < .001, respectively), in the varicocele group. Other hormone levels in the endocrine profile were not significantly different between the groups. Significant negative correlations were found between the elasticity score and testicular volume and the percentage of normal forms (P = .029; P = .005). The varicocele grade showed significant positive correlations with both the strain ratio and elasticity score (P < .001).

CONCLUSIONS

Strong correlations were found between real-time strain elastography and the testicular volume, varicocele grade, and sperm morphologic characteristics. Real-time strain elastography is a simple, noninvasive investigative modality that can potentially be used to study the structure and function of the testicular tissue in varicocele.

Evaluation of the diagnostic efficacy of strain elastography in infertile population with normal and abnormal semen parameters

OBJECTIVE

The aim of the present study was to investigate the diagnostic value of strain elastography (SE) of testicular tissues in infertile population. We also evaluated the correlation between SE results with semen parameters and hormone profiles of the patients.

MATERIAL AND METHODS

A total of 61 patients and 122 testes were evaluated. Patients who were evaluated in an andrology outpatient clinic with the diagnosis of infertility and referred to radiology department for investigation of reproductive organs between June 2015 and January 2016 were included. Patients were divided into two groups according to semen analyses results as normal (Group 1) and abnormal (Group 2). Hormone profiles, semen analyses, B-mode, coloured Doppler ultrasonography and sonoelastography examinations were performed for each patient. Measurements of testicular volumes, resistive indices (RI) in intraparenchymal arteries, strain, strain ratio (SR) and presence of varicocele were recorded.

RESULTS

Mean age of participants was 33.7±6.3 years. Mean testicular volumes (Group 1, 19.41±4.8 mL, and Group 2, 17.64±3.62 mL) were significantly different between groups (p=0.023). Mean SRs were also different between Groups 1 and 2 (0.12±0.08 vs. 0.22±0.18, p<0.001). Testicular volumes were directly proportional with SRs in Group 1. Strain values had inverse relationship with sperm concentration and total motile sperm counts in Group 2 (p=0.01). SRs were found to be positively correlated with RI and sperm morphology in Group 2 (p<0.05). Although FSH values showed significant difference among groups, any correlation between FSH and elastographic parameters could not be displayed.

CONCLUSION

Strain elastography results were found to be significantly different in patients with abnormal sperm counts. This technique may provide promising results, however, further large scale studies may help to clarify the value of this imaging modality in the assessment of male infertility.

Prospective evaluation of scrotal ultrasound and intratesticular perfusion by color-coded duplex sonography (CCDS) in TESE patients with azoospermia

PURPOSE

The objective of this study was to assess whether CCDS might improve the outcome of testicular sperm retrieval in patients with azoospermia. Furthermore, we evaluated potential sonographic alterations of the testis before and after trifocal and Micro-TESE.

METHODS

78 patients were enrolled prospectively: 24 with obstructive azoospermia (OA) and 54 with non-obstructive azoospermia (NOA). 31 of 54 patients in the NOA group had negative surgical sperm retrieval. Testicular volume, hormonal parameters and sonographical findings were compared before and after TESE. The spermatogenetic score was determined for all retrieval sites. CCDS was performed at the upper, middle and lower segment of the testis. Ultrasound parameters and peak systolic velocity (PSV) were measured pre- and post-operatively.

RESULTS

Testicular volume and epididymal head size were significantly increased in OA patients compared to NOA patients. Ultrasound parameters were comparable between NOA patients with and without successful sperm retrieval. A higher intratesticular PSV was significantly correlated with a better spermatogenic score in the corresponding sonographic position. However, after adjustment for other clinical confounders, PSV does not show a significant influence on the spermatogenic score. Testicular volume decreased significantly in all patients post-operatively after 6 weeks (p < 0.001). Finally, the PSV significantly increased in all patients 24 h after surgery and nearly returned to baseline levels after 6 weeks (p < 0.001).

CONCLUSIONS

A higher intratesticular PSV may be helpful as a pre-operative diagnostic parameter in mapping for better sperm retrieval, but CCDS does not help to predict successful testicular sperm retrieval after adjustment for other clinical confounders.

Association of genetic variants in SOHLH1 and SOHLH2 with non-obstructive azoospermia risk in the Chinese population

OBJECTIVE

Spermatogenesis and oogenesis specific basic helix-loop-helix 1 (SOHLH1) and spermatogenesis and oogenesis specific basic helix-loop-helix 2 (SOHLH2) play essential roles for both spermatogenesis and oogenesis. The aim of this study was to evaluate the association of SOHLH1 and SOHLH2 single nucleotide polymorphisms (SNPs) with non-obstructive azoospermia (NOA) in the Chinese population.

STUDY DESIGN

In this study, we assessed 7 single nucleotide polymorphisms (SNPs) of SOHLH1 and SOHLH2 with Sequenom iplex technology in 361 NOA cases and 368 fertile controls.

RESULTS

We found that the SNPs rs1328626 and rs6563386 of SOHLH2 were significantly associated with NOA risk, of which, a protective effect of minor allele T of rs1328626 on NOA (P = 0.038, odds ratio [OR] = 0.799, 95% confidence interval [CI] = 0.645-0.988) and a significantly increased risk of the SNP rs6563386 with the minor allele G to NOA (P = 0.029, OR = 1.402, 95% CI = 1.034-1.9) were observed, respectively. Our data indicated that the haplotype GC of the variants rs1328626 and rs6563386 conferred a significantly increased risk of NOA (P = 0.031, OR = 1.397, 95% CI = 1.031-1.895). Moreover, we found the genotype distribution of rs1328641 was significantly associated with testes volume in the NOA patients (P = 0.022).

CONCLUSIONS

The polymorphisms rs1328626 and rs6563386 of the SOHLH2 gene would be the genetic risk factors for NOA in the Chinese population. The SNP rs1328641 might influence testes development in the NOA patients.

Genetic study of Hormad1 and Hormad2 with non-obstructive azoospermia patients in the male Chinese population

PURPOSE

To evaluate the association of the Hormad1 and Hormad2 single nucleotide polymorphisms (SNPs) variants with non-obstructive azoospermia (NOA) in the Chinese population.

METHODS

In the present study, we assessed 10 single nucleotide polymorphisms (SNPs) of Hormad1 and Hormad2 using Sequenom iplex technology in 361 NOA cases and 368 normal controls from Chinese population.

RESULTS

We observed no statistical differences in the distribution of allele frequencies. Further genetic model analysis and haplotype analysis also showed no significant difference between the two groups. However, we found that genotype distribution of rs718772 of Hormad2 was significantly different between the larger testis group (average testis volume ≥10 ml) and the small testis group (average testis volume <10 ml) in the NOA patients (P = 0.035).

CONCLUSIONS

In conclusion, Hormad1 and Hormad2 might not be the susceptible genes for the non-obstructive azoospermia in our study population. However, rs718772 of Hormad2 variant might be associated with testis development in NOA patients.