Surgical Sperm Retrieval
Men with no sperm in the ejaculate (azoospermia), or sometimes very low numbers and quality of sperm (OATS) may require a surgical procedure to obtain sperm from the testicles or tubes draining the testicles (epididymis). If there is an obvious blockage - for example after vasectomy, congenital absence of, or acquired damage to the vas deferens tubes, sperm may be obtainable from the tubes draining the testicle by passing a needle into them under a local anaesthetic block or sedation. This is called a PESA.
PESA (Percutanous Epididymal Sperm Aspiration)
This is usually performed while you are awake and having injected some local anaesthetic into the area. A needle with some special medium is then passed into the epididymis and some suction applied. In cases of true obstruction / blockage then the success rate is very high in term of finding sufficient sperm for storage and subsequent use in IVF.
What is it is not a blockage?
If there is no apparent blockage of sperm coming out of the testicles, then the other possibility to account for azoospermia is that of testicular failure – otherwise known as Non-Obstructive Azzspermia (NOA). There are a number of causes to NOA (see Infertility section), and the odds of finding sperm vary between the various causes. The odds of finding sperm are significantly lower than in obstruction, as there is a fundamental problem in sperm production. The overall the odds of finding sperm in this situation is around 60%, though the success rate also depends on how the procedure is performed.
TESE (Testicular Exploration with Sperm Extraction)
Historically men with NOA underwent several biopsies from random locations of the testes, to obtain samples of testicular tissue containing sperm producing cells from several areas of the testes. This was most commonly done under a general anaesthetic as if is more invasive than PESA. However there was a possibility of missing an area of sperm production using this method, and it has therefore been largely replaced by a more thorough procedure called microdissection-TESE (or micro-TESE).
