Efficacy of stepwise mini-incision microdissection testicular sperm extraction for nonobstructive azoospermia with varied etiologies

Stepwise mini-incision microdissection testicular sperm extraction (mTESE) is a procedure that attempts to minimize testicular damage. However, the mini-incision approach may vary in patients with different etiologies. Here, we performed a retrospective analysis of 665 men with nonobstructive azoospermia (NOA) who underwent stepwise mini-incision mTESE (Group 1) and 365 men who underwent standard mTESE (Group 2). The results showed that the operation time (mean +/- standard deviation) for patients with successful sperm retrieval in Group 1 (64.0 +/- 26.6 min) was significantly shorter than that in Group 2 (80.2 +/- 31.3 min), with P<0.001. The total sperm retrieval rate (SRR) was 23.1% in our study, and there was no significant difference between Group 1 and Group 2 (P>0.05), even when the etiologies of NOA were taken into consideration. The results of consecutive multivariate logistic regression analysis (odds ratio [OR]: 0.57; 95% confidence interval [CI]: 0.38-0.87; P=0.009) and receiver operating characteristic (ROC) analysis (area under the ROC curve [AUC]=0.628) showed that preoperative anti-M & uuml;llerian hormone (AMH) level in idiopathic NOA patients was a potential predictor for surgical outcomes after initial three small incisions made in the equatorial region without sperm examined under an operating microscope (Steps 2-4). In conclusion, stepwise mini-incision mTESE is a useful technique for NOA patients, with comparable SRR, less surgical invasiveness, and shorter operation time compared with the standard approach. Low AMH levels may predict successful sperm retrieval in idiopathic patients even after a failed initial mini-incision procedure.