THE SURGICAL COLLECTION OF SPERMATOZOA

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Non-obstructive azoospermia (NOA), the most severe type of male infertility in which spermatogenesis is impaired or totally absent, affects approximately 1% of men worldwide. However, the aetiology of most cases of NOA is not defined, being referred to as idiopathic NOA (INOA), posing a worldwide clinical conundrum. Non-obstructive azoospermia (NOA) is associated with intrinsic testicular defects that severely impair sperm production. Although NOA invariably leads to infertility, there may be focal sperm production in the testicles of affected patients, which can be retrieved and used for intracytoplasmic sperm injection (ICSI) during assisted reproductive techniques, giving couples seeking pregnancy the opportunity to respond by generating healthy offspring with homologous gametes. The introduction of intracytoplasmic sperm injection (ICSI) in1992 represented a major breakthrough in the treatment of male infertility. Patients with non-obstructive azoospermia (NOA) can also benefit from the ICSI technique to produce a child as long as spermatogenesis is present. Testicular sperm extraction surgery combined with ICSI insemination is the most effective treatment regimen for NOA patients. There are several techniques to recover testicular sperm in patients with NOA, such as TESA, testicular sperm extraction, or percutaneous testicular biopsies or open biopsies (conventional testicular sperm extraction, TESE). However, sperm retrieval is unfortunately still only successful in a subgroup of patients with NOA, and the most effective method of sperm retrieval is still under discussion. In most cases, the overall success rate in sperm recovery with these techniques varies between 25% and 50%. A more recent technique, testicular sperm extraction microdissection (MD-TESE) with an operating microscope that collects larger and more opaque seminiferous tubules, is a non-blinded sperm retrieval technique with theoretical advantages, which has been shown to achieve significantly better sperm retrieval rates than TESE. It is in contrast to TESA, percutaneous testicular biopsies and TESE, which are all blind techniques. The MD-TESE procedure appears to be feasible, effective and safe in NOA patients but also more technically demanding and time consuming than conventional blind techniques. However, the technique remains not simple as the geographical locations of testicular sperm production areas are uncertain, making microsurgery-guided sperm retrieval by microdissection (micro-TESE) an attractive but still complicated method. The literature suggests that it is an effective and safe method to recover sperm from men with NOA-related infertility, with potential advantages over non-microsurgical methods. Sperm recovery rates with TESA vary, but, with optimal technique, R have been reported up to 35%.

The procedures are preferably performed under local anaesthesia. A median incision is made in the scrotum and the tunica vaginalis is opened. The testis is visualised covered by the tunica albuginea, widely open in the equatorial plane along the median portion. This allows ample exposure of the seminiferous tubules in a physiological approach that follows the intratesticular blood flow. The rest of the procedure is performed under an operating microscope at 20-25x magnification. Small samples are removed from the tubules. Larger and more opaque tubules are more likely to contain sperm. Up to 15 biopsies are taken on each side, but this can vary depending on the size of the testes and tubular status. The procedure is terminated when all areas of the visualised parenchyma have been examined under a microscope or when further dissection is deemed to jeopardise the testicular blood supply. Testicular tissue fragments are placed in IVF medium in sterile Petri dishes and minced using micro-scissors or scalpels. The fractions are placed in droplets of IVF medium, and then well-trained embryologists begin their search for spermatozoa. Prior to surgery, sperm analyses are performed to confirm azoospermia. In addition, serum concentrations of FSH, LH, testosterone and SHBG are analysed to distinguish between obstructive and non-obstructive azoospermia and to exclude hypogonadism. A testicular ultrasound is also performed to exclude scrotal abnormalities such as varicocele, epididymal/testicular cysts, hydrocele and testicular tumours.Complications of TESE are rare (<10%) and usually are minor complications such as bleeding, wound infection, haematoma on the skin of the scrotum or intratesticular accompanied by persistent testicular pain. This haematoma usually reabsorbs within a few weeks; swelling of the testicle that subsides with the administration of analgesics and anti-inflammatories.

 

 

 

References

Arnold P Achermann, et al. Microdissection testicular sperm extraction (micro-TESE) in men with infertility due to nonobstructive azoospermia: summary of current literature. Int Urol Nephrol. 2021 Nov;53(11):2193-2210. doi: 10.1007/s11255-021-02979-4. Epub 2021 Aug 19.

Göran Westlander. Utility of micro-TESE in the most severe cases of non-obstructive azoospermia. Ups J Med Sci. 2020 May;125(2):99-103. doi: 10.1080/03009734.2020.1737600. Epub 2020 Apr 1.

Kaijuan Wang, et al. Micro-TESE surgery combined with ICSI regimen in the treatment of non-obstructive azoospermia patients and its effect analysis. Zygote. 2023 Feb;31(1):55-61. doi: 10.1017/S096719942200051X. Epub 2022 Oct 21.