A varicocele is an enlargement of the veins
that drain the testicle. It is a very common condition present in
15% of the general male population and 40% of men evaluated for
infertility. A varicocele develops because of defective,
small one-way valves that normally allow for
blood to flow away from the testicle toward the heart.
The diagnosis of a varicocele can usually be made on physical
examination of the scrotum while the patient is standing. The
varicocele feels like a "bag of worms" and often disappears or
becomes smaller when the patient lies down. If the patient is asked
to bear down, the backflow of blood can usually be felt in
varicoceles. Some varicoceles are so large they can be seen through
the skin.
When a varicocele exists, the circulation of blood away from the
testicle is impaired. This results in an increased temperature of
the testes which is believed to contribute to compromised sperm
parameters. Increased testicular temperature can damage sperm and
also impede the production of health, new sperm. Therefore,
varicoceles are thought to compromise not only the quality of sperm
but also the quantity of sperm.
There are a variety of techniques that have been used to correct
a varicocele. All methods involve blocking the slow flow that
exists in the dilated veins leaving the testicle (varicocelectomy).
Two common techniques which are used to repair varicoceles are the
microscopic inguinal repair and laparoscopic repair. In
microscopic inguinal repair, a 2-3 cm incision is made in groin to
allow for visualization of the varicocele. Each dilated vein is
then identified and tied off. The laparoscopic varicocele repair
has also been used with great success to treat varicoceles. In this
technique, small incisions are made in the abdomen to allow for
passage of small working instruments. These instruments are used to
identify, dissect, and clip off dilated veins from the testicle as
they enter abdomen.
Men who have undergone a vasectomy and desire sperm in their
ejaculate are candidates for the vasectomy reversal. A vasectomy
reversal is an operation that re-establishes a connection between
the two ends of the vas deferens (vasovasostomy) that were separated
at the time of the prior vasectomy. Sometimes the vas deferens is
reconnected to the epididymus (epididymovasostomy) because of a
secondary obstruction in the epididymus.
Modern reproductive technology has evolved
tremendously to help men who were previously considered to be
incapable of fathering children. The ability to fertilize eggs by
directly injecting sperm into an egg (intra-cytoplasmic sperm
injection) means that very few sperm are needed to achieve a
successful pregnancy. Sperm are produced in the testicle and
transported to the penis where fluid from the prostate combines with
the sperm to produce semen.
Sperm retrieval procedures are necessary in
situations where there are no sperm in a man’s ejaculate. This
condition can result from blockage of the ejaculatory system
(obstructive azospermia) or from failure of sperm production in the
testicle (non-obstructive azospermia). The most common cause of
obstructive azospermia is a prior vasectomy but other causes
include: prior infection, prior hernia repair with mesh or other
prior surgery on the testicles. Non-obstructive azospermia can be
due to genetic conditions, prior testicle infections or hormone
abnormalities. These conditions can interrupt the production of
normal sperm within the testicle. Fortunately, even in these
instances there are often areas of normal sperm production.
The ideal technique for harvesting sperm
depends on a variety of factors. Sperm can be retrieved using an
open surgical approach, or through the skin using a needle. Each
approach has certain risks and benefits and each may not be
appropriate for everyone. Although it is sometimes possible to
harvest enough sperm for intrauterine insemination (IUI), where the
sperm are inserted directly into the woman’s uterus, it is more
common to use harvested sperm for in-vitro fertilization (IVF). The
sperm that are retrieved can be used immediately to fertilize an egg
or can be frozen for use at a later time.
PESA and TESA are similar procedures where a
needle is used to extract sperm from the testicle or epididymis.
The epididymis is an organ that lives behind the testicle and is the
location where sperm mature and develop the ability to move. The
epididymis can be enlarged after a vasectomy or in other conditions
where there is blockage. Both of these procedures can often be
performed with only mild sedation and local anesthetic. A needle is
inserted into the testicle or epididymis and an attempt is made to
collect sperm. The sample collected is immediately examined under a
microscope to look for healthy appearing sperm. These sperm can be
used immediately to fertilize an egg or can be frozen for use at a
later time.
These techniques can be used as a first line
approach for sperm collection. Both PESA and TESA and most
effective when trying to collect sperm in a man who has undergone a
vasectomy and the epididymis is enlarged. The benefits of this
approach are that they are relatively painless and do not require an
incision in the scrotum or a general anesthetic. The risks of the
procedure include bleeding, damage to the epididymis and not being
able to obtain sufficient sperm. If these techniques fail, sperm
may be found using more advanced methods.
MESA is a technique for collecting sperm that
involves using a surgical microscope to open the small tubes within
the epididymis to look for sperm. This technique works well in
conditions where sperm are being produced in adequate numbers but
are blocked from traveling from the testicle to the ejaculate. Examples of such conditions include: a prior vasectomy, prior hernia
repair with mesh, blockage of the seminal vesicles, cystic fibrosis,
and immotile cilia syndrome. This is the favored approach when
harvesting sperm after a vasectomy.
An operating microscope and special skills are
necessary to identify the tubes most likely to contain sperm and the
samples are immediately examined to look for sperm. Sperm harvested
from the epididymis is generally considered better quality than
sperm harvested directly from the testicle because they have had
more time to mature.
This procedure requires a general or spinal
anesthetic and involves an incision in the scrotum to gain access to
one or both testicles. The sperm harvested can be used immediately
or frozen for use at a later time. In cases where no sperm are
found, it is necessary to look in the testicle for viable sperm, a
procedure called TESE or testicular sperm extraction.
TESE is very similar to the MESA procedure.
In a TESE, tissue is taken directly from the testicle and examined
for the presence of sperm. This technique is very successful in
cases of obstructive azospermia where there is blockage of the tubes
responsible for transporting sperm from the testicle to the
ejaculate. However, TESE can also be very useful in patients with
non-obstructive azospermia as well. There are several genetic,
infection related and hormonal conditions that lead to low levels of
sperm production that can be uncovered through surgery.
TESE or micro-TESE (performed with a
microscope) requires general or spinal anesthesia and an incision on
the scrotum to gain access to the testicles. Depending on the
underlying medical condition, the testicle is either incised in
several locations to harvest sperm or completely opened to reveal
all of the sperm producing cells. Several samples are taken and
immediately examined for the presence of sperm. Any sperm found can
be used immediately to fertilize an egg of they can be frozen for
later use. The testicle is then repaired and placed back into the
scrotum. The testicle is generally able to function normally after
the procedure and continue to produce testosterone. This procedure
has been successful in finding sperm is many conditions thought to
result in infertility such as Klinefelter’s syndrome and congenital
absence of the vas deferens.
If there is a high degree of uncertainty about
whether sperm will be found, a couple undergoing TESE will often be
counseled to have the procedure performed before eggs are harvested
or to have a donor sperm sample as a back-up.
Contributing Physician