"Did You Know?" - Understanding Surgical Techniques in the
Treatment of Endometriosis
Information on Endometriosis:
A Monthly Feature
Understanding Surgical Techniques in the Treatment of Endometriosis
By Andrew S. Cook, M.D.
OBGYN.net Editorial Advisor
Laparoscopy & Hysteroscopy
Hysterectomy and Alternatives
Chronic Pelvic Pain
Complete removal of endometriosis is dependent, to a large extent, upon the
skill of the surgeon, and this is true no matter which surgical approaches or
instruments are used. The goal with surgery is to completely remove the
endometrial implants while maintaining as much normal tissue as possible.
The current surgical
tools available to remove endometriosis include: scissors; electrosurgery;
harmonic scalpel; laser; or the endocoagulator. These tools can be used to
excise, coagulate or ablative vaporize (Carbon 13 CO2 laser and high
All surgical techniques
used for removing endometriosis use either mechanical energy (e.g., mechanical
scissors) or thermal energy (heat). Depending on how intense and how high the
heat, one of two effects can occur to the tissue: coagulation or vaporization.
Low-intensity heat results in coagulation, and high-intensity heat results in
Each of the various
surgical techniques available for the removal of endometriosis has certain
advantages and disadvantages. Let's examine each of these:
In the past, coagulation
has been one of the more common surgical techniques used to treat endometriosis.
It is relatively quick, easy to use, and is available at most hospitals.
Coagulation is a burning, or melting, of the tissue. Like any burn it is
difficult to tell precisely how much tissue is destroyed. This is because the
heat spreads slowly, and, just like a sunburn, the extent of the burn may not be
apparent for hours or days. While this is a relatively simple technique to use,
the fact that endometriosis often grows right on delicate organs such as the
bowel, bladder, and the ureters (the tubes from the kidney to the bladder) means
that it is virtually impossible to burn just the right amount of tissue to
completely remove the endometriosis so that none is left behind, and at the same
time avoid damaging normal vital organs. For these reasons, most nationally
recognized surgeons who specialize in the treatment of endometriosis do not
consider coagulation the preferred method for the surgical treatment of
endometriosis (source: 38th AAGL Global Conference on Minimally
Surgical instruments that
can coagulate include monopolar electrosurgery, bipolar electrosurgery, some
types of lasers, the harmonic scalpel, and the endocoaguator.
While it is important to
emphasize that none of the surgical techniques listed above has been shown in
the scientific literature to provide results superior to the others, there does
seem to be a general consensus among nationally recognized endometriosis
surgeons that excision is preferred over coagulation for the treatment of
endometriosis (source: 38th AAGL Global Conference on Minimally
Invasive Gynecology). Remember that complete removal or destruction of the
endometrial implants is the goal of the surgical treatment of endometriosis.
There are two basic
techniques in which a surgeon can remove or destroy the endometriosis: excision
and vaporization. Excision means that the surgeon cuts around and removes
the tissue. Vaporization eliminates the cells of the endometrial implants
by turning the solids and liquids of the cell into vapor. Some types of surgical
lasers, high current electrosurgery, and high intensity ultrasound devices can
deliver very intense energy/heat that instantly boils the water in the cell
(remember, cells are mostly water, with some proteins and other components). The
water turns into steam, vaporizing and thus eliminating the unhealthy tissue.
Excision can be performed
surgically in one of two ways:
Mechanical Excision (ME), or
- By Thermal Excision by Linear Vaporization (TEL-V).
Mechanical Excision (ME)
uses only the mechanical shearing force of scissors, without the aid of
electrosurgery. Thermal Excision by Linear Vaporization (TEL-V) uses
electrosurgery, laser, or the harmonic scalpel to create the intense heat that
results in vaporization. As stated in the American Association of Gynecologic
Laparoscopists (AAGL) publication, even the most die-hard, "excise only"
surgeons who use electrosurgery via scissors are, in fact,
Both Mechanical Excision
(ME) and Thermal Excision by Linear Vaporization (TEL-V) offer several
advantages, and are the mainstay of the successful surgical treatment of
endometriosis. These methods of excision can quickly remove large amounts of
tissue, and provide tissue for the pathologist to check under the microscope.
Neither method damages or alters the appearance of the underlying tissue.
This is an important
point. Whenever tissue is removed, the remaining underlying tissue must be
assessed to determine whether all of the endometriosis was removed or whether
deeper disease is still present. Sounds pretty good so far, but what is the
disadvantage of excision? The primary disadvantage of excision is that it is
fairly non-selective. Endometriosis not only grows on the surface of the
peritoneum (the inside lining of the body), where it can be easily plucked off;
it can also invade the underlying tissue. This invasive endometriosis can send
out "fingers" of endometriosis, growing on and around vital organs (e.g., the
bowel, blood vessels, ureter, bladder, etc.).
If the endometriosis
being removed is separate from vital structures, then excision is a good
approach. But if the endometriosis is growing on vital structures excision is
not always the best choice, as it may require the removal of healthy tissue. In
my opinion, if endometriosis is aggressively removed using only excision, there
will be a higher incidence of bowel resection, ureteral resection, etc., because
"the endometriosis was so advanced." But in reality, appropriate use of
selective ablative vaporization would have removed the endometriosis without
having to resort to removing normal tissue.
There are two basic types
of vaporization: Linear Vaporization and Ablative Vaporization.
Figure 1 – Basic Types of
As mentioned above, virtually all
physicians who excise endometriosis are linear vaporizers using the technique
Thermal Excision by Linear Vaporization (TEL-V). Because vaporization does not
conduct heat, it does not distort the appearance of the cells next to or
underneath the cells that are vaporized. The vaporization is performed in a
line, resulting in a cutting of the tissue. This is the preferred method of most
advanced endometriosis specialists (Source: 38th AAGL Global
Conference on Minimally Invasive Gynecology).
The second type of vaporization is
Ablative Vaporization. For the same reasons that Excision by Linear Vaporization
(TEL-V) is the preferred surgical technique, Ablative Vaporization is acceptable
in limited situations as a touch-up tool after a preliminary process of
excision, with the qualification that it is performed by surgeons who have the
necessary surgical skills to recognize and remove endometriosis. The main
drawbacks to Ablative Vaporization are:
The surgeon must be very
thorough in ablating all of the tissue and not leaving any islands of
endometrial tissue; and
The tissue undergoing Ablative
Vaporization is destroyed and cannot be sent to the pathologist for
For these reasons, Ablative
Vaporization should only be used in select cases as an appropriate secondary
tool in select areas, and not as the primary or sole method of removing
Ablative Vaporization can be
performed with electrosurgery or with a Carbon 13 CO2 laser. This
technique offers several advantages. It is the most precise surgical tool
available for the removal of endometriosis, because the packet of light energy
is so intense and focused that there is no conduction of heat and no
coagulation. Hence there is virtually no thermal (heat) damage to the tissue
that is left behind. It’s important to note that vaporization turns liquid
water into steam, it does not burn tissue. This technique enables the
surgeon to remove the endometriosis layer by layer. Another advantage of
Ablative Vaporization is that the surgeon can examine the appearance of the
remaining tissue, permitting an accurate assessment of whether endometriosis is
still remaining or if normal tissue has been reached. This is especially useful
when working on vital structures such as the bowel, ureters, blood vessels, etc.
endometriosis is considered a benign tumor or at most a tumor of very low
malignant potential, the removal of the scattered endometrial implants with wide
excision and clear margins nevertheless provides the greatest chance of complete
elimination of the disease. Debulking or only partial removal of the
endometriosis will result in the persistence of disease, continued growth of the
endometrial lesions, and most likely relatively rapid recurrence of symptoms2.
For these reasons many endometriosis surgeons feel that excision (with or
without the aid of ablative vaporization) is the preferred surgical technique
for the removal and treatment of endometriosis.
The very nature of heat delivery
with coagulation is imprecise, resulting in a higher chance of both incomplete
removal of the endometriosis and more extensive damage of normal tissue. These
significant drawbacks lead one to consider if the technique of coagulation for
the treatment of endometriosis should be relegated to the past.
it is important to understand the various surgical techniques, the real issue is
the surgeon's skill in identifying and removing endometriosis. Good surgeons may
use variations of the excision and vaporization surgical techniques described
above based on personal preference, with equally good results.
1. Munro MG, Electrosurgery
NewsScope. 2006, July-Sept: 4-5
2. Taylor E and
Williams C. Surgical treatment of endometriosis: location and patterns of
disease at reoperation. Fertil Steril. 2010 Jan;93(1):57-61.