TESTICULAR SPERM ASPIRATION/EXTRACTION
TESA, or testicular sperm aspiration (also known as TESE, or testicular sperm extraction) is one of the surgical sperm harvesting techniques used for retrieving sperm in patients with azoospermia. A number of surgical sperm retrieval or recovery methods have been devised to recover sperm from the male reproductive tract.
In men with obstructive azoospermia,(because of duct blockage or absence of the vas deferens) , sperm are usually recovered from the epididymis
For patients with obstructive azoopsermia in whom sperm cannot be found in the epididymis, it is always possible to find sperm in the testis. The easiest way to retrieve this is through TESA or testicular sperm aspiration , in which the testicular tissue is sucked out through a fine needle, under local anaesthesia. The testicular tissue is placed in culture media and sent to the lab, where it is processed. The sperm are liberated from within the seminiferous tubules (where they are produced) and are then dissected free from the surrounding testicular tissue.
Using sperm from the epididymis and testis for ICSI in order to treat patients with obstructive azoospermia is logical, and thus conceptually easy to understand. However, surprisingly, it is possible to find sperm even in patients who have testicular failure (nonobstructive azoospermia) – even in those men with very small testes. The reason for this is that defects in sperm production are “patchy”- they do not affect the entire testis uniformly
There are 2 options for doing a TESA – diagnostic; or therapeutic. In a diagnostic TESE, the surgeon performs multiple diagnostic biopsies to determine if sperm are being produced in the testes or not. If no sperm are found , the diagnosis of complete testicular failure is confirmed; and treatment options then include adoption or donor insemination, since there is no treatment at present for this condition. If sperm are found, then these testicular sperm can be cryopreserved; and used for ICSI treatment in the future.
The advantage of doing a diagnostic TESE is that it is less expensive; and there is no need to give the wife expensive injections for superovulation.
Unfortunately, the results with testicular sperm cryopreservation are poor very often; which means most men will need a repeat TESE if they want to use their sperm for ICSI. This involves a second TESE, after a gap of about 6 months. There is also a 20% risk that no sperm may be found in the second biopsy, since the first biopsy may have removed all the areas of sperm production.
In our clinic, rather than do a diagnostic TESE, we recommend that patients do a therapeutic TESE-ICSI treatment cycle. If we do find sperm, then these can be used for ICSI immediately, maximising the chances of success. If we do not find sperm, and if patients agree, then we can use donor sperm to fertilise the retrieved eggs. The problem arises if we do not find testicular sperm and the patient is not willing to use donor sperm. In this situation, the ICSI treatment cannot proceed any further.