Testicular biopsy is used to collect sperm
directly from the testis or the tubes conveying sperm from
the testis. The testis might be creating sperm, which may
not be present in the ejaculated semen. This may be for a
number of reasons such as:
- An absence of the tubes that convey the
sperms from the testis –this may due to having had a
vasectomy or it can occur in patients with cystic fibrosis.
- A blockage of the tubing –this may be due to infection.
There are two common approaches to testicular biopsy:
Percutaneous Epididymal Sperm Aspiration
(PESA).
PESA is when a fine needle is inserted into
the tubes that convey the sperm out of the testis. One area
of this tubing, the epididymus, is a natural reservoir for
sperm and is therefore a good place to aspirate them from.
Testicular Biopsy.
If a PESA is not possible or no sperm are
identified then the procedure progresses onto testicular biopsy.
This procedure involves the removal of very small pieces of
tissue from the testis –the Embryologist then processes
the biopsies with a view to finding motile sperm.
The testicular biopsy procedures are performed
under local anaesthetic. The procedure takes about 15 minutes.
Sperm suitable for ICSI are sometimes not
found. It is prudent, therefore, to have some form of sperm
as “back-up” in order that the ICSI treatment
cycles not have to be abandoned.
The sperm recovered by either of these techniques
is only suitable for use with ICSI. Once the ICSI has been
completed and sperm remaining, of good quality, may be frozen
for use with future ICSI cycles.
The success rate for ICSI is typically 25
– 30 % per treatment cycle. However, the success rate
is dependant on many factors, such as the age of the woman.