Many azoospermic patients with nonobstructive azoospermia (NOA) undergo for sperm aspiration as part of their in vitro fertilization procedure. Because sperm might be present in some but not all parts of the testes of such men, multiple samplings of the testicular tissue are usually performed to increase the probability of finding sperm in NOA patients.
These samplings can be done by 2 methods:
MICROTESA: With advances in sperm retrieval techniques, sperm can be found in nearly half of men with non-obstructive azoospermia. Microsurgical testicular sperm extraction (MicroTESE) is a procedure that allows for the precise removal of tiny volumes of testicular tissue is areas of active sperm production using a microscope, improving sperm yield. This approach has a number of advantages over other sperm retrieval techniques. It maximizes the yield of spermatozoa while minimizing the amount of testicular tissue required and vascular injury created, by making identification of blood vessels easier. Sperm harvested from these patients is very difficult to cryopreserve .