Sperm Retrieval Techniques
When a semen sample shows no sperm (azoospermia) , there are several techniques employed to retrieve the sperm from the epididymis or testes.
Two main causes for azoospermia are non-obstructive and obstructive. Non-obstructive azoospermic males have either Sertoli-cell-only syndrome or development arrest of the sperm cells. On the other hand, obstructive azoospermic males generally have reasonable sperm production capacity but the sperm could not be deposited in vagina due to obstruction in the tubes that transport sperm into the penis. Success rates for ICSI with non-obstructive azoospermia are generally lower than ICSI with obstructive azoospermia.
PESA ( Percutaneousepididymal sperm aspiration)
Using a fine needle , the sperm is aspirated from the epididymis
TESA (Testicular sperm aspiration )
Using a fine needle m the sperm is aspirated directly from the testes.
TESE ( Testicular sperm extraction)
A small biopsy is taken from the testes and tested for spermatozoa.
MESA ( MicrosurgicalEpididymal Sperm Aspiration)
An open surgical sperm retrieval procedure that uses an operating microscope to locate the tubules of the epididymis precisely, so that large numbers of sperm can be extracted.