Two Decades from the Introduction of Microdissection Testicular Sperm Extraction: How This Surgical Technique Has Improved the Management of NOA

Abstract

The treatment of men with non-obstructive azoospermia (NOA) has improved greatly over the past two decades. This is in part due to the discovery of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), but also significantly due to improvements in surgical sperm retrieval methods, namely the development of microdissection testicular sperm extraction (mTESE). This procedure has revolutionized the field by allowing for identification of favorable seminiferous tubules while simultaneously limiting the amount of testicular tissue removed. Improving sperm retrieval rates is imperative in this cohort of infertile men as there are a limited number of factors that are predictive of successful sperm retrieval. Currently, sperm retrieval in NOA men remains dependent on surgeon experience, preoperative patient optimization and teamwork with laboratory personnel. In this review, we discuss the evolution of surgical sperm retrieval methods, review predictors of sperm retrieval success, compare and contrast the data of conventional versus mTESE, share tips for optimizing sperm retrieval outcomes, and discuss the future of sperm retrieval in men with NOA.

Predictive factors of successful testicular sperm extraction for non‐obstructive azoospermia with a history of bilateral cryptorchidism and normal testosterone

“…One meta‐analysis showed that larger testicular volume is a significant predictor for successful sperm retrieval in patient with NOA (Corona et al., 2019); however, another study demonstrated that even testicular atrophy does not preclude successful sperm retrieval (Bryson et al., 2014). Although normalising serum testosterone seems to be important, the proof of this strategy had not been achieved and the results are conflicting in literature (Punjani et al., 2021; Reifsnyder et al., 2012).…”

Technological Advancements in Male Infertility Microsurgery

“…Schlegel and Li presented a video of microdissection testicular sperm extraction (mTESE), a technique where the testicle is bivalved, and the size and color of individual tubules are analyzed for the most likely tubules to contain sperm [ 26 , 27 ]. While there have been reports, as well as a large systematic review, and meta-analysis suggesting similar sperm retrieval rates between conventional and mTESE, at least in the NOA population, these data should be interpreted cautiously as it is mainly based on non-randomized and heterogeneous data [ 2 , 28 ]. The one randomized study in this review did suggest a benefit for mTESE [ 2 ].…”

“…While there have been reports, as well as a large systematic review, and meta-analysis suggesting similar sperm retrieval rates between conventional and mTESE, at least in the NOA population, these data should be interpreted cautiously as it is mainly based on non-randomized and heterogeneous data [ 2 , 28 ]. The one randomized study in this review did suggest a benefit for mTESE [ 2 ]. Importantly, this technique is notably less traumatic to the blood supply of the testis as the vasculature can be directly visualized, and sperm retrieval rates are relatively high, given the ability to directly visualize the seminiferous tubules prior to harvest [ 26 , 29 ].…”

“…Historically, there were limited treatment options for men with severe male factor infertility, azoospermia, or no sperm in the ejaculate. However, there have been significant advancements to male infertility surgical methods, including the use of microsurgery, which has permitted more options and improved outcomes in these men [ 2 ]. That being said, there remains significant room for advancement in male infertility microsurgical methods and technology.…”

Update on the Management of Non-Obstructive Azoospermia: Current Evidence and Unmet Needs

“…The introduction of mTESE in 1999 greatly improved the chance of retrieving testicular sperm in patients with NOA, by enabling the identification of foci of spermatogenesis at high magnification even in patients with nearly atrophic testes. In the two review papers coauthored with Nahid Punjani and Caroline Kang, the pioneer of this surgical technique, Prof. Peter N. Schlegel, illustrates how to manage patients with NOA and optimize the success of mTESE [ 8 ], and sheds light on the reproductive chances of men with NOA according to the underlying etiologies (Klinefelter syndrome, Y chromosome microdeletions, chemotherapy-associated NOA, cryptorchidism) [ 9 ]. Both papers are a must read for reproductive urologists.…”