Evaluation of vasovasostomy candidates by deoxyribonucleic acid flow cytometry of testicular aspirates

Vasovasostomy: A systematic review and meta-analysis comparing macroscopic, microsurgical, and robot-assisted microsurgical techniques

BACKGROUND AND OBJECTIVES

Vasovasostomy is a cost-effective procedure for the reversal of vasectomy. A water-tight adequately blood-supplied mucosal anastomosis is required for better outcomes. This review aimed to compare the outcome of vasovasostomy performed by three different techniques: macroscopic, pure microsurgical, and robot-assisted microsurgical techniques.

METHODS

Scopus, Web of Science, PubMed, Embase, and Cochrane library databases were searched for relevant studies from January 1901 to June 2023. We conducted our quantitative syntheses using the inverse variance method in OpenMeta software. The study's protocol was registered on PROSPERO.

RESULTS

This review involved 95 studies of different designs, with a total sample size of 48,132. The majority of operations were performed bilaterally, and participants were monitored for up to 10 years. The pooled patency rate was the highest following robot-assisted vasovasostomy (94.4%), followed by pure microsurgical vasovasostomy (87.5%), and macroscopic vasovasostomy (83.7%). The pooled pregnancy rate following purely microsurgical vasovasostomy was higher than that of macroscopic vasovasostomy (47.4 vs. 43.7%). Definitive pregnancy rates in robotic vasovasostomy are yet to be determined.

CONCLUSION

Patency outcomes for vasovasostomy were best with robot-assisted microsurgical technique, followed by pure microsurgical technique, and conventional macroscopic technique. Further investigations of robot-assisted microsurgical vasovasostomy outcomes and randomized control trials are required to support this evidence.

Image analysis assessment of the abnormal testis biopsy in male infertility

PURPOSE

We previously demonstrated that testis biopsy image analysis is an effective method for quantifying intratubular spermatogenic cells in the obstructed testis with normal spermatogenesis. As an extension of the initial report, we describe using the quantitative ploidy and morphological characteristics of cells counted with image analysis in abnormal testis biopsies obtained for a male infertility evaluation.

MATERIALS AND METHODS

Image analysis using a specifically designed filter was performed on Feulgen stained 5 microns, sections of paraffin embedded testicular tissue. Archival testicular tissue had been obtained using standard biopsy techniques from patients with azoospermia or severe oligospermia. Qualitative classification was based on standard evaluation of hematoxylin and eosin processed tissue.

RESULTS

There were 62 biopsies performed in 58 men. Significant differences in the intratubular content of haploid (spermatozoa and spermatids), diploid and tetraploid cells were found among the 5 categories of abnormalities: the Sertoli-cell-only syndrome, spermatocyte arrest, spermatid arrest, hypospermatogenesis and normal spermatogenesis. Moderate variability was found in the proportion of cell types in spermatid arrest and hypospermatogenesis.

CONCLUSIONS

Testis biopsy image analysis provides a quantitative method for categorizing abnormalities of intratubular cell content present in male infertility states by using deoxyribonucleic acid content and morphology characteristics. The limitations of the present qualitative analysis system are emphasized by the moderate variability evident within the current categories of spermatid arrest and hypo-spermatogenesis states.

Assessment of spermatogenic process by deoxyribonucleic acid image analysis

OBJECTIVE

To evaluate the spermatogenic process through cellular ploidy by image analysis.

DESIGN

Twenty-six testicular aspirates from 24 infertile men were examined by fine needle aspiration (FNA) cytologic smears. These results were compared with the ploidy content of the cells using Feulgen stain, determined by image analysis.

RESULTS

The results of both methods were divided into three categories: full spermatogenesis, spermatogenic arrest, and only Sertoli cell. There was a good correlation in 25 of 26 smears (96%). Ten patients who had a histogram of diploid showed only Sertoli cell cytologically. From nine patients who had a histogram of diploid and tetraploid, eight cytologically showed spermatogenic arrest and one showed full spermatogenesis. The seven patients who had full spermatogenesis (haploid, diploid, tetraploid) all had normal cytologic smears.

CONCLUSIONS

Deoxyribonucleic acid image analysis is an objective qualitative and quantitative method for the evaluation of the spermatogenic process of the infertile male. It has several advantages over the flow cytometry method.

Quantification of spermatogenesis by dual-parameter flow cytometry

OBJECTIVE

To investigate the usefulness of dual-parameter flow cytometry of testicular fine-needle aspirates for the quantification of spermatogenesis. Immunofluorescence staining for vimentin was introduced to discriminate vimentin-negative germ cells from vimentin-positive stromal cells. The results of flow cytometry were compared with testicular morphology and immunohistochemistry in cases of regular and disturbed germ cell maturation.

DESIGN

Testicular fine-needle aspiration and surgical biopsy were performed in 50 autopsy cases. The fine-needle aspirates were double stained for the intermediate filament vimentin by indirect immunofluorescence and DNA propidium iodide and analyzed by flow cytometry. Surgical biopsies were examined by light microscopy. The distribution of vimentin-positive cells was evaluated by immunohistochemistry.

RESULTS

A comparison of morphology and flow cytometric analysis yielded characteristic quantitative distribution patterns of the different germ cell and somatic cell populations in regular and disturbed spermatogenesis. All three ploidy compartments of the germ epithelium correlated with high statistical significance with the respective histologic diagnoses. Moreover, a marked quantitative increase of stromal cells could be demonstrated in spermatogenetic disorders.

CONCLUSIONS

The simultaneous analysis of the cellular DNA content and the intermediate filament vimentin by flow cytometry enables a detailed investigation of spermatogenetic disorders. Quantitative changes of the relationships between germ cells and somatic cells can be selectively investigated.

The value of quantitative testicular biopsy and deoxyribonucleic acid flow cytometry in predicting sperm recovery from electrostimulated ejaculates

Spermatogenic abnormalities have been reported in the majority of men following spinal cord injury, and they contribute to the multifactorial etiology of reproductive dysfunction. Thus far, few have studied the seminiferous epithelium in this group of patients by objective criteria. While quantitative micrometry and flow cytometric analysis are accurate and reproducible methods of quantitating spermatogenesis, the latter is simpler and permits needle aspiration for tissue recovery. The objective of this study is to determine the value of quantitative micrometry and flow cytometric analysis as methods of predicting total sperm yield in electrostimulated ejaculates. Incisional testicular biopsy was performed in 12 anejaculatory men, and the tissue specimens were divided for analysis by quantitative micrometry and flow cytometric analysis. Quantitative micrometry consisted of determining the mean tubular wall thickness, mean tubular concentration of the Sertoli cells and mature spermatids in a minimum of 10 round seminiferous tubules per patient. Specimens were prepared for flow cytometric analysis and the deoxyribonucleic acid histogram was analyzed to determine the percentage of cells in each ploidy compartment. Of the quantitative micrometry parameters analyzed a significant correlation resulted between the total sperm yield per electroejaculate and the mean tubular concentration of late spermatids (p = 0.001) as well as with the mean tubular ratio of late spermatids to Sertoli cells (p = 0.003). The tubular concentration of spermatids resulted in a sensitivity and specificity of 100% and 75%, respectively, to predict adequate sperm yield in semen. Likewise, the mean tubular ratio of spermatids to Sertoli cells resulted in a sensitivity and specificity of 75% and 87.5%, respectively, in its ability to predict normal sperm yield in the recovered ejaculate. Deoxyribonucleic acid flow cytometry analysis showed a normal haploid compartment in all 6 specimens studied, and each was associated with high numbers of sperm in recovered semen. Quantitative histometric parameters correlate significantly with the total sperm yield obtained in electrostimulated ejaculates and may have a role in the selection of candidates for treatment in reproductive rehabilitation programs.

Deoxyribonucleic acid flow cytometry and semiquantitative histology of spermatogenesis: a comparative study

OBJECTIVE

To compare deoxyribonucleic acid (DNA) flow cytometry with a semiquantitative histologic method for the assessment of spermatogenesis and to investigate the influence of various preparative techniques on the results of DNA measurements.

DESIGN

Testicular tissue from 52 autopsies was examined for spermatogenesis by DNA flow cytometry and by conventional semiquantitative histology. Flow cytometry was performed on single nuclei suspensions from fine needle aspiration biopsies, resuspended imprints, as well as on specimens obtained by mechanical disaggregation of surgical biopsies of the same testis.

RESULTS

In all cases, flow cytometry revealed a characteristic distribution pattern of haploid (n), diploid (2n), and tetraploid (4n) cells independent of the preparation technique used. The percentage of haploid cells of the testes showed statistically highly significant correlations (P = 0.0002) with the results of semiquantitative histology. Fine needle aspiration biopsy always contained more haploid cells compared with resuspended imprints and mechanically disaggregated samples.

CONCLUSION

Our results confirm the suitability of DNA flow cytometry as a fast and reliable quantitative method for the assessment of spermatogenesis and demonstrate its optimal feasibility in combination with fine needle aspiration biopsy.

Comparison of flow cytometry to routine testicular biopsy in male infertility

We compared DNA flow cytometry to morphologic evaluation of routine testicular biopsies as methods of monitoring spermatogenesis. The study group consisted of 14 azoospermic men and 5 others who underwent testicular surgery unassociated with fertility problems. The findings for both studies were divided into three groups: normal, moderately abnormal, and markedly abnormal. Correlations between the findings from routine biopsy and flow cytometry were good. Of 9 patients having normal testicular morphology, 7 had normal ploidy classes by DNA flow cytometry while 2 had moderately abnormal histograms. Of 5 cases with moderately abnormal morphology, 1 had normal, 1 had moderately abnormal, and 3 had markedly abnormal ploidy distributions. In 5 cases described as Sertoli cell only, all DNA histograms were markedly abnormal, consisting almost exclusively of diploid cells. DNA flow cytometry of testicular biopsies and aspirates has been demonstrated to be a rapid, reproducible, and objective approach in evaluating the infertile male and is a promising method to investigate spermatogenesis in an outpatient clinic in lieu of formal testis biopsy.

The clinical application of aspiration deoxyribonucleic acid flow cytometry to neurologically impaired men entering an electroejaculation program

For the neurologically impaired patient electroejaculation with a rectal probe can furnish sperm for artificial insemination. However, documentation of pregnancies in this patient group has been limited. Deoxyribonucleic acid flow cytometry has been shown to be a reproducible quantitative method with which to evaluate spermatogenesis. We assessed the ability of deoxyribonucleic acid flow cytometry on testicular aspirates to predict the quality of sperm production in 13 men undergoing electroejaculation. Semen analysis was performed on antegrade and retrograde specimens. Deoxyribonucleic acid histograms from testicular aspirates were evaluated for the relative proportions of haploid, diploid and tetraploid cells. These ratios were compared to the means reported for our own series of 25 patients who at vasovasostomy had sperm intraoperatively and to the similar figures from a group of 10 accident victims. Five patients had normal testicular ploidy compartments defined as within 2 standard deviations from control means. Of the 5 patients 4 had normal sperm counts and motilities (30 per cent or greater). Two patients have contributed sperm for artificial insemination; 1 has resulted in pregnancy. Three patients had moderately abnormal (2 to 4 standard deviations) testicular ploidy classes. These patients had adequate sperm counts but low motilities (5 per cent or less). Of the 5 patients with markedly abnormal (greater than 4 standard deviations) histograms 4 remained azoospermic despite repeated attempts at electroejaculation. Our data support the use of deoxyribonucleic acid flow cytometry on testicular aspirates as a predictor of which patients might succeed and those who are unlikely to succeed in an electroejaculation program.