Simply a variation on the Testicular Fine Needle Aspiration Technique TEFNA procedures of
medicine’s early days, the sperm mapping technique involves the drawing of a 9-12 sectioned “grid”
the testicle and the blind (not guided by a microscope or other imaging that can “show” the doctor what he
or she is actually doing) insertion of a needle into each area to remove a small portion of the
seminiferous tubules that can be sampled for sperm production.
We should pause here a moment to discuss the danger of internal bleeding caused by a punctured blood
vessel. Because testicular mapping is not visually guided, the physician can’t be certain he is
blood vessels during the process of inserting the needle. Of course this danger is also multiplied by the
number of times (9-12 in most cases) that the needle is inserted.
The removed samples from each grid section are placed on a microscope slide, stained with cytological
chemicals that fix and kill the sperm and the slides are reviewed by a special laboratory doctor
(cytopathologist). A “map” is then made of each of the sections sampled from the testicular grid and plotted
points are placed on it for the areas where sperm were or were not found. If sperm are identified during the
sperm mapping procedure they aren’t obtained in a way that allows them to be used for an IVF/ICSI procedure
and another later procedure will need to be performed to retrieve them in a usable way. If sperm are not
found, then the patient is typically told he is infertile. There is no guarantee that if a patient has a
small area of sperm production then it will be found on the mapping procedure.
At best, sperm mapping is an expensive diagnostic exam that may or may not reveal productive areas
within the testicle which will need to be harvested during another expensive procedure at a later date. At
worst, it prescribes a devastating infertility diagnosis which may be false. Today, neither of the above
testicular mapping outcomes is considered ideal because a more precise, less invasive and more cost
effective option is available – it is called Micro-TESE
Testicular Mapping & Random Testicular Biopsy – A Thing of the Past
When it comes to harvesting sperm in patients with a blockage, the random testicular biopsy and needle
aspiration has its place in the world of reproductive medicine. But when searching for healthy and usable
sperm in men with Non-Obstructive Azoospermia (NOA) who are trying to conceive a child with their partner,
it isn’t the best, safest or most effective option.
In the early days of reproductive medicine, limited and blind sampling of the testicle via needle (gun)
biopsies is how most general urologists performed testicular biopsies on men with fertility concerns. A few
small, random pieces of testicular tissue containing seminiferous tubules would be removed, without being
able to view their appearance or the process of their retrieval under a microscope first, a key fertility
success element we can achieve today. Once collected, the samples where then sent to a pathologist (a doctor
who examines tissue samples from the body) to mount on slides and examine cross sections of the tissue under
a microscope to see if there were sperm inside.
Unfortunately, too many general urologists still assess fertility in this limited and incomplete way.
Today, we know that how the seminiferous tubules in men with NOA appear, reveal some obvious
differences between the few tubules producing healthy sperm and the tubules that aren’t. To the
experienced eye of a well-trained micro-surgical male fertility specialist, the healthy tubules appear
larger and fuller than the tubules that aren’t producing healthy sperm. Those unhealthy tubules look
collapsed, whitish in color and scarred. Because the healthy and unhealthy tubules look so different from
one another, the chances of finding sperm increase – with a trained expert and the right technology.
Unfortunately, due to the way the samples are obtained, random testicular biopsy doesn’t allow for this
level of specific and focused examination.
Sometimes the physician performing the testicular biopsy will use a spring-loaded needle gun that is only
able to remove a small sliver of testicular tissue without making an incision. The tissue is then delivered
to the pathologist for special testing. Unfortunately, the process used by the pathologist to prepare the
slides for examination also kills any sperm that are present in the testicular biopsy tissue samples. When
this happens, the ability to obtain an overall understanding of whether the sperm are alive, moving or how
mature they are is destroyed. But even more importantly, random testicular biopsy doesn’t allow the “good
sperm” to be salvaged, preserved and frozen for later use in an IVF/ICSI procedure.
What this means is that a man whose biopsy has discovered healthy sperm will have to undergo another
surgery to get more sperm to later use for IVF/ICSI. On top of that, up to half of the men with NOA who are
actually making some sperm will have none found by these blind testicular biopsies (because they didn’t
sample the “good” seminiferous tubules). These men will be told they are infertile and they will lose the
chance to become a biological parent.
Testicular biopsies are called “blind” or “random” because the doctor can’t view the seminiferous tubules
they are removing. The blindness of the procedure also increases the danger that the physician may puncture
a blood vessel that they can’t see, causing internal bleeding and further complications.
In the case of men with NOA, biopsy of the testicle performed by general urologists is not the most
effective way to approach fertility solutions and can actually cause more harm than good. Less than a third
of the men who are tested in this way will indeed have small amounts of sperm production and they will be
misdiagnosed as infertile. The have sperm found will be required to undergo a second surgery to get sperm
that can actually be used. For men with NOA, random testicular biopsy can be avoided in favor of a more
precise and accurate procedure Micro-TESE.