Approximately 10–15% of infertile men suffer from azoospermia, while about 40% suffer from obstructive azoospermia (OA). This obstruction may be attributed to bilateral occlusion at any point in the reproductive ductal system, which comprises of the efferent duct, epididymis, vas deferens, and the ejaculatory ducts. Unlike the USA, EOA is rarely caused by vasectomy rather by infection in China [12, 13]. The microsurgical anastomosis, including microsurgical vasovasostomy (VV), cross vasovasostomy (CVV), and vasoepididymostomy (VE), is considered as the most successful measure for a reversal [14]. Herein, we discussed the modified single-armed 2-suture longitudinal intussusception vasoepididymostomy. The data were similar to the previously reported patency rate of 52–92% and the pregnancy rate of 11–56% [15, 16]. In the present cohort, we evaluated the pre-, intra-, and postoperative variables of individual patients that might affect the outcomes of the modified SA-LIVE.
The VE with the double-armed suture is the standard golden management for the EOA, and LIVE simplifies the anastomosis and improves the outcomes [7, 17]. However, in China, these specialized double-armed sutures for male infertility microsurgery are challenging, while access to single-armed microsurgical sutures is easy [18]. Furthermore, the cost of a single-armed sutures was cheaper than that of the double-armed microsurgical sutures. Therefore, SA-LIVE should be designated as an effective alternative when double-armed sutures are not available. When the needles are in the tubule, the two sutures in a lower position can avoid the crossing of the sutures [6]. The two knots of the suture are left outside during the procedure, which might decrease the possibility of fibrosis and anastomotic stricture. However, the single-armed suture is time-consuming as compared to the double-armed suture, which was placed inside-out on the vas deferens to avoid back-walling the tubular lumen. Since the single-armed suture was used in this study, the needle passed through the inferior points of the vasal mucosal layer in an outside-in manner through the epididymal tubule, and finally through the superior points of the vasal mucosal layer in an inside-out fashion, which was double time-consuming than the double-armed suture, thereby increasing the risks of surgery. Also, we had to dilate the vasal lumen sufficiently wide to pass the needle through the lumen with the aid of a microneedle holder to avoid back-walling during the suture placement. Supposedly, these procedures must be completed before the presence of the sperm in the epididymal fluid [19]. However, if no sperm was detected, the procedure was repeated 2–4 times, which would significantly increase the time required for the surgery and the fatigue of the surgeon.
In this cohort, the patency and the pregnancy rates were similar to those reported previously [12]. However, no statistically significant associations were found between the patency rate and various predictors, such as bilateral or unilateral anastomosis and anastomotic site (P > 0.05; Tables 2 and 3). Moreover, the natural pregnancy rate was 0% for the proximal anastomosis group, while it was 33.3% for the distal group, which prompted us to investigate whether patients can benefit from proximal anastomosis. Firstly, the luminal diameters of epididymal tubules in the caput were significantly smaller than those in the corpus and caudal, and hence, the modified SA-LIVE on the distal epididymis was more accessible than that on the proximal epididymis. Moreover, spermatozoa could become fully motile as well as recognize and fertilize an egg within the epididymis, which might improve the pregnancy rate. As the sample size was not sufficient for further investigation, the reason for the failure of the technique is yet to be determined.
Although there have been many clinical studies on VE, none proposed a specific follow-up time frame on SA-LIVE. The current study revealed that 87.8% of the patients achieved patency within six months post-operation, and none achieved patency since then, suggesting that SA-LIVE on patency can be followed up to 12 (average: 4.11±2.74) months. The patency rate for the first six months was 48.5% (65/134) and 11.4% (9/69) for the next six months. Previous data on the mean time to achieve patency after vasovasostomy and vasoepididymostomy ranged from 1.7–4.3 and 2.8–6.6 months, respectively [12], which is in agreement with the current results. This finding could be valuable for the clinicians and researchers to predict the outcome of patients undergoing SA-LIVE as well as the precise time to transfer to ART.
Notably, four patients were diagnosed as non-obstructive azoospermia in other hospitals previously according to the negative results of the testis histopathology; however, we found motile sperm through the routine testicular biopsy. Thus, the scheduled operation of microdissection was transferred to VE, and 3/4 patients achieved patency afterward. This suggested that the testis biopsy during the operation is essential [20].
Also, one patient, who had undergone VE in another hospital previously was subjected to VE operation due to the previous failure. Consequently, sperm appeared in the ejaculate, and finally, this couple achieved a spontaneous pregnancy. Thus, we concluded that in addition to ICSI, a second VE surgery might be a possibility for those patients who failed the first operation.
Interestingly, VE is an effective treatment for azoospermia patients with epididymal obstruction and previous failure to achieve pregnancy by sperm retrieval with ICSI [21]. Three patients diagnosed with OA chose to use the sperm from testicular puncture for ICSI in another hospital but failed possibly due to miscarriage, maturation arrest in utero, or the failure of embryo transfer [21]. After undertaking SA-LIVE in our hospital, all the patients achieved patency: one had natural pregnancy, one underwent IVF after the surgery, and one is still trying to get a natural pregnancy. Furthermore, MEV has significant advantages, such as cost-efficiency, spontaneous pregnancy possibilities, and decreasing the potential risks of congenital disability as compared to ICSI. Thus, microsurgical reconstruction is an effective treatment and should be the first choice for epididymal obstruction patients whose female partners have normal fertility features. Thus, EOA patients with prior failure of ICSI could consider taking LIVE to get pregnant.
This study revealed that if sperm did not show up in the ejaculate after one-year post-operation, ART might be the remedy for such patients. Thus, intra- or postoperative sperm cryopreservation would be helpful. Intraoperative sperm cryopreservation could avoid the additional surgeries for sperm retrieval in case of failure of microsurgery. Postoperative sperm cryopreservation allows sperm from the ejaculate to be used for ART in the event of late failure. In the current cohort, we found out that one patient who achieved recanalization of the vas experienced a recurrence of obstruction after six months at the rate of 0.07%, which was lower than that reported previously (1–50%) [12, 22]. Sperm cryopreservation was used for a total of 132 patients. Of these, 29 patients who were not successful by vas-mediated patency achieved pregnancy through ICSI by the sperm cryopreserved intraoperatively, and nine successful patients chose to use the sperm from ejaculate to have babies through ART. The pregnancy rate was improved from 30.3% to 43.9%. With the development of the ART technique in the recent decades, the influence of whether the sperm on the next generation was unclear irrespective of its origin from testis or post-epididymis. Thus, taken together, we advocate intra- or postoperative sperm cryopreservation for all OA patients.