TESTICULAR MAPPING IN MEN WITH NOA: GREAT IDEA OR COLOSSAL WASTE OF TIME?
What’s The Best Treatment Approach for Men With Non-Obstructive Azoospermia?
We’ve Come A Long Way, Baby
Advances in reproductive medicine over the last 10 years have allowed men who were previously considered absolutely sterile to father biological children. Those advances have come on two fronts. The first was the advent of In-Vitro Fertilization (IVF) with Intra-Cytoplasmic Sperm Injection (ICSI).
This technological breakthrough reduced the requirement of the number of sperm needed to fertilize an egg from millions to just one sperm per egg. It meant that men with very low sperm counts that could not be improved with other means had a new way of effectively conceiving. It also led us to reexamine our understanding how the testicles function.
It turns out that men who have no sperm in the ejaculate because of problems with sperm production, a condition called Non-Obstructive Azoospermia (NOA), actually may have small pockets of sperm production within the testicle. In fact, greater than 60% of men with NOA actually do produce small amounts of sperm inside the testicle that can be used with IVF/ICSI to create a baby.
Sounds like great news all around, right? Well, the challenge for experts has been to develop techniques that improve the chances of finding sperm inside the testicle and then to create effective strategies to best harvest that sperm IN THE SAME PROCEDURE, for use with IVF.
What we know for certain is that the ability to magnify and see the seminiferous tubules (include glossary pop-up of ST definition here) doubles the chances of finding sperm in a man with NOA from 30 to 60 percent. Let’s further explore the treatment options that may help or hinder our ability to accomplish this goal.
One treatment approach called testicular mapping, was developed to sample multiple areas of the testicle in an effort to improve the chances of finding sperm. In this technique, a grid is drawn over the testicle and a needle is blindly inserted into each grid area to remove a small section of the tubules and then sample them for sperm. The removed sections are analyzed by a cytologist (specialized pathologist) and a map is then made of each testicle showing which areas had sperm found in them.
Unfortunately, when sperm are found using this “mapping” technique, the tools used to perform it don’t extract very many sperm. In the best case, when sperm are present, another microsurgical procedure must be performed to find those tubules (again) that have sperm and to remove enough for use in IVF treatments or to freezing for future use.
This means that men who undergo successful mapping will be required to have a second surgery on their testicles in order to have a child. The advantage to mapping is that if no sperm are found then it is reasonable to assume there isn’t any sperm production within the testicle and no reason for the couple to undergo an IVF cycle.
The dilemma arises because statistically, most men with NOA DO have some degree of sperm production. So, with Testicular Mapping, most men will have this unnecessary procedure performed to find out if they have sperm before going through the process of actually being able to use the sperm for freezing or IVF.
Microsurgical Testicular Sperm Extraction (micro TESE, Testicular Microdissection)
The best way of finding sperm that can be used for IVF is via a surgical procedure called microsurgical testicular sperm extraction or micro-TESE. This approach uses an operating microscope to examine the seminiferous tubules within different areas of the testicle. Because we can oftentimes select the best and most normal appearing tubules when we magnify and visualize them, we can significantly improve the chances of finding sperm. Using this approach, we can also remove more tubules and examine all areas of the testicle under the microscope and therefore get the maximal amount of sperm possible from a given patient.
What this means for patients is that in ONE procedure we can:
1. Determine if/in which specific areas of the testicle sperm are being produced and
2. In the same procedure, extract the highest-quality sperm for freezing or use in IVF.
In our experience, most couples choose to time the micro-TESE in conjunction with the egg retrieval portion of an IVF cycle so that the sperm can be incubated for a day or two without having to freeze them and can be injected into the eggs.
This offers the statistically best chances of men with NOA to father a child.
Take Home Point
The technological advancements of IVF/ICSI and Micro-TESE give couples with NOA the best chances of conceiving. Testicular mapping is an unnecessary diagnostic procedure that only checks if sperm are present but does not allow for sperm harvesting and freezing. Most men who undergo mapping will be required to have a micro-TESE procedure to get sperm to use anyway and will have undergone the mapping procedure but not gotten any benefit from it. It is important that patients understand this before making a decision on how best to proceed.