Microsurgical Testicular sperm extraction in the management of non obstructive azoospermia - micro TESE

Microsurgical Testicular sperm extraction in the management of non obstructive azoospermia

 

Testicular tissue. Captured by surgical microscope during micro TESE procedure. Magnification 10X

      Azoospermia is the complete inability of finding any sperm in the ejaculate after multiple centrifugations. There are two types of azoospermia: 

i) obstructive, where there is a complete, bilateral obstruction somewhere in the seminal tract and 

ii) non obstructive, (up to 86% of all azoospermia cases) where the problem is that the testes do not produce any mature spermatozoa that can reach the seminal tract to come out by ejaculation.              

      The main question for a man who suffers azoospermia is “will I ever have my own biologic children?” The answer is very easy to give in the case of obstructive azoospermia (OA): the man can undergo a surgical procedure in an effort to bypass the obstruction so that the semen returns in his ejaculate, or, if it is no possible, there is a 100% possibility that the urologist will find plenty of spermatozoa in his testes that can be used in ICSI, by percutaneous needle aspiration or a single, classic testicular biopsy.

     When it comes however in non obstructive azoospermia (NOA), things are quite different: for many years, until very recently (1993), these men was thought to be completely sterile, with no chance of biological paternity.   Prior to the availability of assisted reproductive technologies, the use of donor sperm was the only option offering a realistic chance of conception for couples affected by non obstructive azoospermia. The approach to azoospermic patients has changed dramatically  with the introduction of sperm retrieval techniques and assisted reproductive technologies, especially intracytoplasmic sperm injection (ICSI).  ICSI offered new possibilities for achieving pregnancy with sperm retrieved from the testis.

      It has been shown that mature spermatozoa can be found in only part of the testes of NOA patients. Testicular spermatozoa can be retrieved from some NOA men despite the absence of ejaculated spermatozoa in their semen because of the existence of isolated foci of active spermatogenesis.

     The most appropriate  method for retrieving testicular sperm in non-obstructive azoospermia (NOA) is open testicular biopsy (testicular sperm extraction: TESE). Micro-TESE is an advanced version of TESE that applies microsurgical techniques to identify individual seminiferous tubules that are more likely to contain active spermatogenesis.

The optimal technique for sperm extraction should submit the following citeria:

• it should be minimally invasive and
• avoid destruction of testicular function
• without compromising the chance to retrieve adequate numbers of spermatozoa for several  ICSI cycles.

     Microsurgical Testicular Sperm Extraction (micro-TESE), performed with an operative microscope, is widely considered to be the best method for sperm retrieval in NOA, as larger and opaque tubules, presumably with active spermatogenesis  can be directly identified, resulting in higher spermatozoa retrieval rates with minimal tissue loss and low postoperative complications. In picture 1 you can see the advantage of micro-TESE in testicular tissue access. In pictures 2,3,4,5,6 and 7 you can see intraoperative snapshots of how we see testicular tissue under great magnification and how "normal" testicular tubules are beeing one by one identified and extracted . 

                                             Picture 1.

Picture 2.                               Picture 3.                         

                            Picture 4.                                            Picture 5.                            
         

                                                  Picture 7.

  

Picture 6.

     Using micro TESE we can retrieve sperm adequate for two or three cycles of ICSI in 48 - 63 % of cases,when the classic testicular open biopsy is succesful in only 16,7 - 45%. It is very important, that micro-TESE is also effective for patients in whome conventional TESE has failed. In these patients, with previous unsuccessful classic biopsies, sperm retrieval with micro-TESE can be achieved in up to 51%. Micro-TESE, in combination with ICSI, is applicable in all cases of NOA, including Klinefelter syndrome (KS).

     In conclusion, micro-TESE is the method of choice in the treatment of non obstructive azoospermia and a unique chance of azoospermic men to become biologic fathers.  

Reference

Tomomoto Ishikaw. Surgical recovery of sperm in non-obstructive Azoospermia . Asian Journal of Andrology (2012) 14, 109–115