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Figure 8.2.7. Hysteroscopic view of the central adhesion connecting
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the uterine walls.
3.5%, mannitol 5% – which provide excellent visualization and
are useful distending media. When dividing these adhesions, the
resectoscopic loop may not be the appropriate electrode to use
because it is designed to resect rather than to selectively divide
the adhesions centrally. When the resectoscopic loop has been
used for this purpose, several complications have occurred, particularly as a result of future sacculations of the uterus, dehiscences, and perforations. Ascertaining where the adhesions fin-
Intrauterine Adhesions: Hysteroscopic Evaluation and Treatment — 147
Figure 8.2.9. Extensive central intrauterine adhesions on hysterosalpingogram.
ish and where the normal myometrium begins is difficult, and
the resections may be so deep that a portion of the myometrium
may be shaved during division of the adhesions. Electrodes, such
as the knife or wire types that can selectively be directed to
the adhesions and divide them systematically, have been specifically designed for this purpose. Nonetheless, concern remains
about scattering the energy and damaging the peripheral healthy
endometrium. With the use of specific electrodes, this effect may
be somewhat decreased. It is important to monitor the operation with concomitant laparoscopy or sonography because the
landmarks of junction between adhesions and myometrium may
be lost, and the coagulating effect this energy may produce in
the myometrium may obscure a view of small vessels that, when
bleeding, warn the hysteroscopist to stop further dissection (Figures 8.2.9–8.2.15).
Figure 8.2.8. Following treatment, the uterine cavity achieves symmetry.
Figure 8.2.10. Systemic hysteroscopic division ofadhesions with semirigid scissors.
148 — Rafael F. Valle
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Figure 8.2.11. Complete division of theadhesions results in asymmetric uterine cavity.
Use of the resectoscope has few advantages. Bleeding is
decreased during dissection because of the electrical coagulating
effect. The resectoscopic continuous flow system allows estimation of the deficit of fluid, thus decreasing the chances of fluid
overload.
There are also disadvantages. Monopolar energy must be
used. Only fluids devoid of electrolytes can be used. Additionally, electrosurgical damage of peripheral healthy endometrium
and the loss of landmarks may occur while coagulating close to
the myometrium, resulting in inadvertent invasion of this area.
Finally, electrical damage to surrounding organs with or without
perforation is a risk.[16]
Treatment of intrauterine adhesions with fiberoptic lasers,
such as the neodymium: yttrium–aluminum–garnet (Nd:YAG),
Figure 8.2.13. Following the initial hysteroscopic treatment, a small
neocavity is obtained with remaining thick fibrotic stumps.
argon, and KTP/532,mayalsobeusedtodivideintrauterineadhesions. However, their application has been somewhatlimited.The
Nd:YAG laser with sculptured or extruded fibers may be a useful tool to selectively divide intrauterine adhesions, particularly
those that are lateral and fundal.[15] Care must be taken to use
these fibersby contact andselectively be aware of the overall symmetry of the uterine cavity, because the coagulating power of the
laser may cause an effect similar to that of electrosurgery – that
Figure 8.2.12. Hysterosalpingogram showing extensive uterine cavity
occlusion and deformity with a small central tract made by uterine
sounding.
Figure 8.2.14. Extensive fibrotic adhesions involving a large portion of
the uterine cavity.
Figure 8.2.15. Extensive occlusion of the uterine cavity with fibrotic
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adhesions. A small island of the uterine cavity at 3 to 4 o’clock is free
of adhesions.
is, coagulation and cutting – and the landmarks of the juxtaposed myometrium may be lost while performing division of
the adhesions. Small arteries that cross the myometrium may
not bleed, so dissection may proceed further than necessary. The
hysteroscopic manipulation of the fiberoptic lasers is very easy
and is facilitated by the use of oblique telescopes. The argon
and KTP/532 lasers use the sharpest fibers to cut rather than to
coagulate.[17]
Because lasers are not conductive, fluids with electrolytes
should be used. Normal saline, dextrose 5% in half normal
saline, and Ringer’s lactate provide excellent visualization and
contain sodium if excessive fluids are absorbed. The use of these
electrolyte-containing fluids will not prevent pulmonary edema
but will decrease the risk of hyponatremia; therefore, more fluid
may be usedthan when usingfluids devoid of electrolytes.Ideally,
a hysteroscope with a continuous-flow system – or one with true
inflow and outflow – should be usedto monitor the injected fluid
and keep a perfect account of the deficit or nonrecovered fluid.
Use of thelaser is attractiveand has the benefit ofeasy manipulation, but requires more time than useofmechanicaltools,such
as hysteroscopic scissors. It is important, therefore, when using
this type of energy to expedite the procedure as much as possible
so as to prevent excessive fluid from being intravasated.
Of late, vaporizing electrodes have been introduced in an
attempt to use them with electrolytic solution distending the
uterus. Concerns similar to those with electrosurgery apply, particularly without evaluation of the penetration and scattering
these electrodes produce when applied to tissues.
The treatment of severe intrauterine adhesions remains a
challenge, and other methods have been suggested to simplify
the treatment, such as concomitant fluoroscopy or sonography, transfundal uterine injection of dyes, coaxial injection of
Intrauterine Adhesions: Hysteroscopic Evaluation and Treatment — 149
radiopaque material, vital dyes to distinguish fibrous adhesions
from residual endometrium, endometrialelectrosurgical scoring,
blind lateral sounding of the uterine cavity, and hysterotomy for
transfundal dissection of the adhesions. However,all these methods have been used in a limited fashion and have not consistently
proved their efficacy.[18]
INTRA- AND POSTOPERATIVE MANAGEMENT
The principal goal of therapy is to remove the adhesions surgically. Because most of these patients have a sclerotic or destroyed
endometrium, they need other adjunctive therapy to promote
reepithelialization and a mechanical separation of the uterine
walls to prevent the reformation of adhesions. These adjuncts
are intrauterine splints, prophylactic antibiotics, and estrogens,
to promote reepithelialization.
Prophylacticantibiotics are used routinelyin these patients in
view of a traumatized endometrium and theextensive manipulation these patients usually require. The antibiotics used are in the
form of cephalosporins:cefazolin,1 g intravenous (IV) piggyback
1 half-hourbefore the procedure, followed by cephalexin, 500 mg
four times dailybymouth(PO) for aweek,shouldan intrauterine
splint be placed. Additionally, in patients with extensiveintrauterine adhesions, an indwelling 8F pediatric Foley catheter is inserted
and 3.0 to 3.5 mL of a sterile solution instilled. The catheter is left
in place for a week to prevent reformation of adhesions. Adjunctive hormonal therapy consists of conjugated estrogens in the
form of Premarin (Wyeth Pharmaceuticals), 2.5 mg twice daily
for 30or 40 days, depending onthe extent of uterine cavity occlusion and the type of adhesions found. The more extensive and
old the adhesions, the more prolonged the hormonal treatment
must be. In the last 10 days of this artificial cycle, medroxyprogesterone acetate (Provera, Pfizer), 10 mg a day, is given PO for
10 days, to induce withdrawal bleeding. Upon completion of the
hormonal treatment, and once withdrawal bleeding has ceased,
a hysterosalpingogram is performed to assess the results of the
operation and decide on further therapy or initiation of attempts
atconception.Patients with filmy, focaladhesionsmaynotrequire
HSG, but may need an office hysteroscopy to assess uterine cavity
symmetry.[3,19]
RESULTS OF TREATMENT
The results of hysteroscopic treatment of intrauterine adhesions
havecorrelatedwell withtheextentofuterinecavity occlusion and
the type of adhesions present. Normal menstruation is restored
in over 90% of the patients.[3,19] The reproductive outcome correlates well with the type of adhesions and the extent of uterine
cavity occlusion. Of 187 patients treated hysteroscopicallybyValle
and Sciarra [3], removal of mild, filmy adhesions in 43 cases gave
the best result, with 35 (81%) term pregnancies. In 97 moderate cases of fibromuscular adhesions, 64 (66%) term pregnancies
occurred; and in47 severe cases of connective tissue adhesions,15
(32%) term pregnancies occurred. Overall restoration of menses
occurred in 90% of the patients, and the overall term pregnancy
rate was 79.7%. These results demonstrate a much better reproductive outcome than was previously obtained with blind methods of therapy (Table 8.2.1).
150 — Rafael F. Valle
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Table 8.2.1: Hysteroscopic Lysis of Intrauterine Adhesions
Results Reproductive Outcome
Study Patients, no. IUD E/P Antibiotics NL Menses (%) Pregnant (%) Term (%)
Edstrom (1974) 9 +−−211
March and Israel
(1981) [19]
Neuwirth et al.
(1982) [15]
Sanfilippo et al.
(1982)
Siegler and
Kontopoulos (1981)
[5]
Hamou et al. (1983) 69 ++−59 (85.5) 20 (51.3) 15 (38.4)
Sugimoto et al.
(1984)
Wamsteker (1984) 36 +++34 (94.4) 17 (62.9) 12 (44.4)
Friedman et al.
(1986) [16]
Valle and Sciarra
(1988) [3]
Zuanchong and
Yulian (1986) [see
18]
Lancet and Kessler
(1988) [21]
Pabuccuetal.
(1997) [22]
Feng et al. (1999)
[23]
Totals 1298 1060 (87.5) 718 (72.3) 603 (87.2)
38 +++38 (100) 38 (100) 34 (79.1)
27 +++20 (74) 4 (51.8) 13 (48.1)
26 ++−26 (100) 6 (100) 3 (50)
25 Foley catheter +−13 (52) 11 (44) 6 (24)
258 ++−180 (69.7) 107 (41.4) 64 (24.8)
30 −+−27 (90) 24 (80) 23 (76.6)
187 +Foley catheter ++167 (89.3) 143 (76.4) 114 (60.9)
70 +++64 (84.3) 30 (85.7) 17 (48.5)
98 Hyskon Flexible scissors,
electrosurgery
40 Glycerin Murphy probe scissors 33 (82.5) 27 (67.5) 23 (57.5)
365 Dextrose 5% Biopsy forceps/scissors 294 (83.7)
98 (100) 86 (87.8) 77 (89.5)
∗
156 (83.8) 145 (92.9)
∗
, of 186 desiring pregnancy; −, xxx; E/P, estrogen/progesterone; NL, normal; +, positive; −, negative.
Modified from Siegler AM Valle RF, Lindemann HJ, Mencaglia L. Therapeutic Hysteroscopy: Indications and Techniques. St. Louis: CV Mosby;
1990:103.
Results following treatment of intrauterine adhesions using
the resectoscope have been similar; nonetheless, the reported
postoperative complications may be serious and should be kept
in mind when using thistype ofinstrument. A fewseries reported
lysis of adhesions with fiberoptic lasers, but when the lasers are
used appropriately, results should not vary much from those
reported with electrosurgery.[16,20]
markedly improved surgical results. The hysteroscopic treatment
of intrauterine adhesions provides the opportunity for restoration of the uterine cavity’s symmetry, which resolves menstrual
abnormalities, and leads to improvement of reproductive function with the removal of the causes of repetitive abortions and
infertility. All these salutary effects greatly support the hysteroscopic approach for women affected with intrauterine adhesions
as the method of choice in their management. The treatment
of intrauterine adhesions can be accomplished by four different
SUMMARY AND CONCLUSIONS
techniques: scissors, resectoscope, fiberoptic lasers, and vaporiz-
ing bipolar electrodes.All have advantages and disadvantagesand
The introduction of hysteroscopy has provided gynecologists
with a simplified and less invasive method of treatment for
many conditions affecting the uterine cavity that in the past
required major surgery. Undoubtedly, one of the conditions
that has benefited from the hysteroscopic approach is the management of intrauterine adhesions. This approach has offered
a more accurate evaluation and more refined treatment, with
must be used with knowledge of each particular technology and
its drawbacks. Each technique should be tailored not only to the
anatomy, embryology, and etiology of eachprocess but also to the
experience and knowledge of the operator. The operator should
select the appropriate method and technique for each patient.
In the treatment of intrauterine adhesions, the semirigid scissors
guided by thehysteroscope offer thebest alternative for treatment
Intrauterine Adhesions: Hysteroscopic Evaluation and Treatment — 151
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of this condition. The goalsoftherapyshouldbe a successful pregnancy for those patients with impaired reproduction, keeping in
mind the safety of the patient, with the least morbidity possible, the absence of complications, the overall effectiveness, and
diminution of unnecessary cost. [8] Versatility plays a significant
role in the selection of therapeutic alternatives; the surgeon has
to intelligentlyselect the best method for each individual patient.
REFERENCES
1. Asherman JG. Amenorrhea traumatica (atretica). JObset Gynaecol
Br Emp. 1948;55:23–30.
2. Asherman JG. Traumatic intrauterineadhesions. J Obstet Gynaecol
Br Emp. 1950;57:892–896.
3. Valle RF, Sciarra JJ. Intrauterine adhesions: hysteroscopic diagnosis, classification, treatment, and reproductive outcome. Am J
Obstet Gynecol. 1988;158:1459–1470.
4. Foix A, Bruno RO, Davidson T, Lema B. The pathology
of postcurettage intrauterine adhesions. Am J Obstet Gynecol.
1966;96:1027–1033.
5. Siegler AM,KontopoulosVG.Lysis ofintrauterineadhesionsunder
hysteroscopic control: a report of 25 operations. JReprodMed.
1981;26:372–374.
6. March CM, Israel R, March AD. Hysteroscopic management of
intrauterine adhesions. Am J Obstet Gynecol. 1978;130:653.
7. Siegler AM, Valle RF. Therapeutic hysteroscopic procedures. Fertil
Steril. 1988;50:685–701.
8. The American Fertility Society. Classifications of adnexal adhesions, distal tubal occlusion, tubal occlusion secondary to tubal
ligation, tubal pregnancies, mullerian anomalies, and intrauterine
adhesions. Fertil Steril. 1988;49:944–955.
9. Schenker JG, Margalioth EJ. Intrauterine adhesions: an updated
appraisal. Fertil Steril. 1982;37:593–610.
10. Dmowski WP, Greenblatt RB. Asherman’s syndrome and risk of
placenta accreta. Obstet Gynecol. 1969;34:288–299.
11. Klein SM,GarciaCR.Asherman’s syndrome:acritiqueandcurrent
review. Fertil Steril. 1973;24:722–735.
12. Valle RF, Sciarra JJ. Current status of hysteroscopy in gynecologic
practice. Fertil Steril. 1979;32:619–632.
13. Confino E, Friberg J, Giglia RV, Gleicher N. Sonographic
imaging of intrauterine adhesions. Obstet Gynecol. 1985;66:
596–598.
14. VartiainenJ,KajanojaP,YlostaloPR. Ultrasonography in extended
placental retention and intrauterine adhesions: a case report. Eur
J Obstet Gynecol Reprod Biol. 1989;30:89–93.
15. Neuwirth RS, Hussein AR, Schiffman BM, Amin HK. Hysteroscopic resection ofintrauterine scars using anew technique. Obstet
Gynecol. 1982;60:111–113.
16. Friedman A, Defazio J, DeCherney AH. Severe obstetric complications following hysteroscopic lysis of adhesions. Obstet Gynecol.
1986;67:864–867.
17. Newton JR, Mackenzie WE, Emens MJ, Jordan JA. Division of
uterine adhesions (Asherman’ssyndrome) with the Nd-YAG laser.
Br J Obstet Gynaecol. 1989;96:102–104.
18. Valle RF. Intrauterine adhesions (Asherman’s syndrome). In:
Marty R, Blanc B, deMontgolfier R, eds. Office and Operative Hys-
teroscopy. New York: Springer-Verlag; 2002:229–242.
19. March CM, Israel R. Gestational outcome following hysteroscopic
lysis of adhesions. Fertil Steril. 1981;36:455.
20. Intrauterine adhesions. In: Siegler AM, Valle RF, Lindemann HJ,
Mencaglia L. Therapeutic Hysteroscopy: Indications andTechniques.
St. Louis: CV Mosby; 1990:82–105.
21. Lancet M, Kessler I. A review of Asherman’s syndrome, and results
of modern treatment. IntJFertil. 1988;33:14–24.
22. Pabuccu R, Atay V, Orhon E, et al. Hysteroscopic treatment
of intrauterine adhesions is safe and effective in the restoration of normal menstruation and fertility. Fertil Steril. 1997;68:
1141–1143.
23. Feng ZC, Yang B, Shoo J, Liu S. Diagnostic and therapeutic
hysteroscopy for traumatic intrauterine adhesions after induced
abortions: a clinical analysis of 365 cases. Gynaecol Endosc.
1999;8:95–98.
Section 8.3. Hysteroscopic Myomectomy
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Charles J. Ascher-Walsh and Michael Brodman
The introduction of the hysteroscopic myomectomy represented
a revolution in the treatment of uterine fibroids. Thousands of
women worldwide have avoided more invasive surgical treatment in the form of a hysterectomy by using the hysteroscope to
treat relatively minor problems,such as submucosalmyomasand
endometrial polyps. The combination of technologic advances
in luminescence, electrosurgery, and metalwork has allowed surgeons to diagnose and treat intrauterine pathology in ways that
greatly decrease patient discomfort and risk and minimize the
number of lost productive days. The resectoscope is an essential
tool for the gynecologist desiring to provide his or her patient
with the best available options.
HISTORY
Hysteroscopic myomectomy has classically been performed with
an instrument called a resectoscope. Newer therapies use other
instrumentation and are discussed in a later section; however,
the bulk of hysteroscopic myomectomies performed today continue to be done using the resectoscope. Gynecology borrowed
this technology from urology. Before Neuwirth and Amin [1]
reported the first case of using a resectoscope for the treatment
of a submucosal myoma in 1976, urologists had been using the
device for decades.
The development of the resectoscope resulted from scientific
advancements in avariety offields. Current resectoscopes require
a light sourcetobeabletosee thepathology, afenestratedsheathto
reach the pathology both visually and with instrumentation, and
an electric cutting source to resect the pathology. After Thomas
Edison invented the incandescent lamp in 1879, it was just over
20 years before ReinholdWappler and William Otis presented the
first American-made cystoscope to the American Association for
Genito-Urinary Surgeons in 1900.[2]
By 1926,advances in technology allowed Bumpus to describe
what could be seen as the earliest predecessor to our current
resectoscope. He combined a cylindrical knife attached to a highfrequency current designed for coagulation with a fenestrated
sheath and light source. The combination of these components
for transurethralresection of thehypertrophied prostrate wasthe
basis for all future designs. In that same year, the first reported
case describing the use of a device described as a “resectoscope”
was published by Maximilian Stern.[3] His device consisted of
an insulated shaft in which was placed a 0.5-cm tungsten cutting
loop attached to an electrical current. The loop was situated at a
right angle to the shaft and placed over a defect in the shaft at the
distal end. Thisend was placed over the prostate, and theloop was
moved away from and toward the viewerto cut the hypertrophied
tissue.
The first report of the use of electrosurgery in humans came
from the French physicist d’Arsonval.[4] He demonstrated in
1893 that using alternating currents of 2 kHz to 2 MHz caused
tissue heating and cutting without muscle or nerve stimulation.
Surgeons began to use electrosurgical techniques while performing a variety of surgeries. At the same time Stern was developing
his resectoscope, William T. Bovie developed an electrosurgical
unit for tissue cautery that was first used by Harvey Cushing on
October 1, 1926, at the Peter Bent Brigham Hospital in Boston
to remove a vascular myeloma.[5] Joseph McCarthy took advantage of this new technology by modifying the resectoscope to
include a magnifying lens and improved insulation of the sheath.
He reported these advances and the instrument’s use in the New
England Journal of Medicine in 1932.[6]
Iglesias and his colleagues [7] further modified the resectoscope to a model thaturologistsand gynecologists continue to use
today. They addeda second sheath aroundthe current design that
allowed for a separate outflow tract. This allowed for continuous
irrigation, which allowed the procedure to be performed with
less bladder pressure. The constant flow also resulted in better
visualization. They reported on this in 1975, and within a year,
Neuwirth and Amin [1] were reporting on its use for resecting a
submucosal myoma. It was the addition of the outflow tract that
allowed its use for this purpose and brought on a revolution in
gynecologic surgery.
INSTRUMENTATION
The gynecologic resectoscope used today is a modification of the
urologic resectoscope. The primary difference is a blunter distal
end. The instrumentation is similar to that found in operative
hysteroscopy, with the addition of an electrode and electrosurgical device. Standard equipment of hysteroscopy includes the
hysteroscope, a light source, a video camera, and a medium for
distention.
The standard resectoscope comes in a variety of sizes, typically between 24F and 28F. These resectoscopes all use a 4-mm
telescope and have separated inflow and outflow sheaths. There
are smaller resectoscopes with 3-mm telescopes, but these are
not well suited for resecting submucosal myomas and are more
appropriate for polyps or intrauterine adhesions. The telescopes
vary from 0
◦
to 30◦, depending on operator preference. The 12
telescope seems to be best suited for resection of a myoma as it
allows for best, continuous visualization of the electrode. In the
◦
scope, the electrode may impair a significant part of the visual
0
field; inthe 30
field. The 12
◦
scope, the electrodemay extend beyond thevisual
◦
telescope allows for complete visualization of the
◦
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electrode through its entire range of motion while having only
a small amount of visual field obstruction. Depending on the
brand, the telescopes have a panoramic field of vision between
◦
and 120◦. Thefocus isset on infinity, whichmagnifies objects
70
more the closerthey are to thelens. The telescopes are designedto
provide the best visualization 30 to 35 mm from the lens. Operators should try a variety of instruments to determine which one
they find most appropriate for each situation.
The sheaths have fenestrations to allow for different tracts
for the camera, electrode, inflow distention medium, and outflow medium. The distention medium flows in through the inner
sheath. On some devices, this is the port most proximal to the
eyepiece. Others havethe inflow and outflow at the same distance
from the eyepiece. For these devices, the inflow is found on the
same side ofthedevice as the attachment for theelectric cable. It is
important to attach the inflow and the outflow correctly as there
is more resistance inthe outflow sheath. This increasedresistance
allows forthe distention of the uterine cavity. The increasedpressure from the distended uterine cavity results in an equilibrium
between the inflow and outflow tracts. The open cavity and continuous movement of fluid allow for better visualization of the
uterine cavity and potential pathology within it.
Although the distention fluid is discussed in the next section, the devices used to instill and monitor the fluid are equally
important. There are a variety of devices available, from those
as simple as a hand pump to provide enough force to push the
fluid intoand distend the cavity, to complex pressure devices that
vary inflow to maintain specific intrauterine pressures and collect the outflow fluid to monitor fluid deficits. The hand pump
is typically much less expensive than the fluid monitoring units.
It allows the surgeon to control the inflow of fluid, allowing for
a rapid change in flow to correct poor visibility due to a lack
of distention or to fluid clouded by blood. However, use of a
hand pump relies on the surgeon to not overdistend the cavity, which may lead to a more rapid absorption of the distention medium. Because hypotonic distention medium is the most
common type of medium used, a fluid imbalance may lead to
serious sequelae from hyponatremia, including death. Hysteroscopic myomectomy will frequently require a significant amount
of time to complete, making fluid balance an important issue.
Surgeons considering new equipment for hysteroscopy should
seriously consider some of the newer devices that allow closer
monitoring of fluid deficits so as to decrease the risks to their
patients. Surgeons using older devices need to be aware of these
risks and to adjust their setup and techniques to minimize these
risks. Using drapes that have fluid-collecting pockets that are
placed under the buttocks so that fluid is not lost onto the floor
or using floor suction devices can minimize the amount of fluid
that is not accounted for during the procedure.
The electrode most frequently used for hysteroscopic
myomectomies is the loop electrode. Electrodes also come in
other types, including the roller ball, barrel, and point electrodes
used for a variety of procedures, including endometrial ablation,
removal of adhesions or polyps, and resection of a uterine septum. The loop electrodes have versions in which the loop is situated at angles of 0
commonly used electrode for myomectomies is the 90
◦
,45◦,90◦, and 120◦from the shaft. The most
◦
loop.
The electrodes are attached to a high-frequency electrosurgical unit preferably with a digital wattage indicator, such as the
commonly used unit from Valleylab called the Valleylab Return
Electrode Monitoring Circuit. The most commonly used current
for hysteroscopic myomectomy is monopolar. The VersaPoint
unit by Gynecare is a bipolar unit and is discussed in the section
on newer devices. A monopolar current in electrosurgery is an
alternating radiofrequency current that runs from the generator
through theelectrode to the surgical site.Because the surgical site
does not conduct the current as well as the electrode, it is rapidly
heated, and cutting and coagulation are accomplished by this
method. The current is then dispersed throughout the body so
that it loses any power within a few millimeters of the electrode.
It is again collected at the grounding pad and returned to the
generator, which completes the electrical circuit. Most electrical
units offer a cutting or coagulation current or a blend of the two.
The electrical current is represented by a sinusoidal waveform. A
cutting wave is a continuous wave, whereas a coagulation wave
is made up of intermittent bursts. The power of the waveform,
measured in watts, is determined by the voltage and the time
delivered. Because coagulation waveforms are intermittent and
hence have an actual current only 25% of the time, equal voltage
peaks in cutting andcoagulationcurrentsresultinalowerwattage
for the coagulation current. To achieve equal wattage – that is,
setting the generator on equal settings for both cutting and coagulation currents – the voltage peaks must be significantly higher
in the coagulation current. With higher voltage peaks, the force
behind the flow of electrons, although intermittent in the case of
coagulation, is higher and the electrons can be driven deeper into
the tissue. This makes the use of the coagulation current slightly
more dangerous as the thermal spread of tissue destruction is
greater.
Tissue is cut by the intracellular fluid being rapidly heated
to the point at which the cell is literally vaporized. As the cell
is torn apart by vaporization, the tissue is cut. The continuous
waveform is better at creating this vaporization than is the intermittent coagulation waveform. The intermittent current results
in a slower heating of cells. Depending on the type of cell being
treated, the coagulation waveform may still be used to cut tissue,
especially if it is moved quickly through the tissue, although it is
more likely toslowly desiccate and fulgurate the tissue,eventually
leading to carbonization. Intracellular fluidis a good medium for
conducting electricity, so when the fluid is vaporized by the cutting current, the low peak voltage is not able to drive the current
further into the tissue.Theintermittentcoagulationcurrent heats
the cells more slowly, so the water in the cells does not flash into
steam. The cells are dehydrated more slowly.The higher peakcurrent of the coagulation current allows it to be driven further into
the tissue, continuing to heat the tissue until only the carbon is
remaining. Itis for this reason that a cutting current allows for an
easier and safer removal of submucosal myomas. The electrode
tends to pass through the tissue with less resistance, and there is
less risk of thermal spread, which is important as one approaches
the uterine serosa during the removal of larger myomas.
DISTENTION MEDIA
The uterine cavity is a potential space and hence requires some
type of medium to distend it so that surgery can be performed.
Because of the vascular nature of the uterus, the media used to
distend the cavity may be absorbed. The higher the pressure used
for distention, the greater the media absorption. It is therefore
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important to choose the best medium for the job at hand. The
perfect substance would be isotonic and havelittle impact on fluid
volumes in the body. Its absorption would not cause electrolyte
abnormalities. It would allow forgood visualization. It would not
cause hemolysis and would not conduct electricity. It would also
allow for easy cleaning of the instruments after use, and the fluid
itself would be inexpensive to use. This perfect medium does not
exist, however,and one mustweigh the risks and benefits of available media when choosing which one to use for each procedure.
The following media have been used for uterine distention:
carbon dioxide, Hyskon, Ringer’s lactate (RL), normal saline
(NS) and half normal saline, glycine, sorbitol, mannitol, cytal
(sorbitol and mannitol), and dextrose 5% in water (D
W). For
5
our purposes, the discussion islimitedtofluid thatissuitedforthe
resectoscope. RL and NS contain electrolytes and are conductive.
The current diffuses in every direction away from the electrode,
and no cutting effect is found. They are therefore not suited for
the resectoscope. D
W and water are nonconductive; however,
5
they are rapidly absorbed and can lead quickly to a dangerous
state of hyponatremia. Hyskon is an electrolyte-freesolution with
extremely high viscosity. It is composed of dextran 70 in 10%
dextrose. It is very thick and slowly absorbed. The high viscosity
makes it very difficulttouse in thecontinuous-flow resectoscopes
currently available. More importantly, unless meticulously cared
for, Hyskon left in hysteroscopes and resectoscopes can quickly
ruin the equipment. Because of this latter problem, most
surgeons have found it too costly to continue its use.
Glycine is the fluid most commonly used in resectoscopic
surgery today. It has also been the most commonly used fluid
by urologists. The fluid is 1.5% of the amino acid in water. It
is a hypotonic fluid, having an osmolality of 200 mOsm/L.[8]
This osmolality causes minimal hemolysis but may cause significant hyponatremia and fluid overload. Glycine is metabolized to
ammonia and glyoxylic acid in the liver and kidney. The ammonia is excreted as urea, and the glyoxylic acid is further reduced
to oxalate and excreted by the kidney. Glycine’s plasma half-life is
approximately 85 minutes. Surgeons frequently check intraoperative or immediately postoperative serum sodium levels for confirmation of hyponatremia. This problem will worsen, however,
as the glycine is metabolized and should therefore be rechecked
at least an hour after the procedure to be sure that the problem
is not worsening.
Sorbitol and mannitol are sugar solutions with similar chemical characteristics, although they are broken down in different
ways. They both are nonconducting fluids that are good for visualization and use in continuous-flow devices. Both are hypotonic
and, likeglycine,maycausefluidoverloadandhyponatremiawith
excessiveabsorption. Whereas sorbitolis broken down to glucose
and fructose, mannitol remains mostlyunmetabolized. Mannitol
is excretedquicklybythe kidney and actsasadiuretic,counteracting the hyponatremia and fluid overload. Asa medium, it may be
the best suited for the resectoscope, although mannitol alone has
a higher viscosity so may be slightly more difficult to work with.
Most resectoscope cases use glycine as the distention fluid.
Given the risks of hyponatremia and fluid overload, it is important to understand the mechanisms of distention as well as the
complications that are caused by hyponatremia and the ways in
which it is treated. Fluid absorption is related to a number of
factors within the uterus. Fluid is absorbed through the vascularity of the uterus. The greater the uterine pressure, the higher
the rate of fluid absorption. Visualization adequate for surgery
can usually be achieved with pressures between 75 mm Hg and
100 mm Hg. Any amount of pressure over this will usually not
add tovisibility butwill only increase the rate of fluid absorption.
In low-tech units that do not incorporate the monitoring of fluid
pressure, placing abag of low-viscosity fluid1 m above thesupine
patient will result in a pressure of 73 mm Hg whereas placing it
1.5 m above the patient will increase the pressure to 110 mm
Hg.[9] Hand pumps can significantly increase the pressure to
values far in excess of what is necessary for appropriate visualization. The best units are those that closely monitor the pressure
necessary to inject the fluid and maintain this pressure at levels
less than 100 mm Hg. These units should also involve an underbuttock drape to assure total outflow collection and a return
system that correctly determines the fluid deficit in a continuous
fashion.
Absorption of hypo-osmolar low-viscosity fluids such as
glycine may lead to fluid overload and hyponatremia, which can
potentiallyresultinthedeathofthepatient.Continuousmonitoring should occur during the case. Once a deficit of1Lisreached,
the surgeon should begin to conclude the procedure. The deficit
should not surpass 1.5 L, and once this deficit is approached, the
procedure should come to an immediate conclusion. If greater
than 1 L is lost, the patient should be monitored in the recovery room and serial serum sodium levels should be checked. As
glycine or sorbitol is metabolized, serum sodium may continue
to rise, even after the completion of the procedure. If the serum
sodium level increases after an initial period of observation of
at least 30 minutes, and the initial serum sodium was at least
125 mmol/L, it is safe to discharge the patient. The highest
reported serum sodium that still resultedin cerebellar herniation
and death was 121 mmol/L, reported by Baggish et al.[8] The
signs and symptoms of hyponatremia include an initial bradycardia and hypertension. The patient may then develop nausea,
vomiting, seizures, pulmonary edema, and cardiac abnormalities. Without correction, thefinal stage is comaand death, usually
caused by cerebral edema due to the hypo-osmolar state leading
to cerebral herniation through the brainstem.
Treatment of hyponatremia should be instituted as soon
as it is recognized. Frequently, this simply means stopping the
procedure. If significant hyponatremia is suspected, a diuretic
such as furosemide should be given immediately. Although
chronic hyponatremia is expressly not treated with diuretics,
acute hyponatremia, especially in this setting, is. Electrolytes
should be monitored serially. In the setting of severe hyponatremia – that is, serum sodium levels less than 120 mOsm/L –
central monitoring may be considered to assess the complex
changes in hemodynamics that may ensue. Normal saline should
be given instead of hypertonic solutions to prevent ensuing hypernatremia. Serum sodium may be increased up to 2 mEq/L per
hour. Too rapid correction of hyponatremia may lead to central
pontine myelinolysis. Although it is more likely to occur in the
correction of chronic hyponatremia, it still is a risk in the acute
surgical setting and can be avoided by not using hypertonic solution or the rapid infusion of normal saline.
PATIENT EVALUATION AND PREPARATION
Fibroids are one of a number of structural abnormalities in the
uterus that may cause abnormal bleeding. The list also includes
Hysteroscopic Myomectomy — 155
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endometrial polyps, endometrial hyperplasia or cancer, and adenomyosis. Numerous studies are available that attempt to differentiate among the possible causes. The most important first step
is a thorough history and physical. A postmenopausal woman
or teenager with abnormal bleeding is much less likely to have
fibroids as a cause than is a 45-year-old woman with excessive
menstruation. The teenager should be evaluated for anovulatory
or otherhormonalcausesofabnormalbleeding, whereasthepostmenopausal woman should be evaluated to rule out endometrial
cancer. A long history of irregular menses, every 3 to 4 months,
that are frequently excessive is more likely to point to a hormonal
cause of abnormal bleeding compared with a recent, progressive increase in the volume of menstruation in a woman with an
enlarged uterus on exam, which more likely indicates myomas
as the cause. Although the history and physical may not give an
absolute diagnosis for the abnormal uterine bleeding, they often
point to the direction of focus to achieve this diagnosis and, hence,
the appropriate treatment.
If a structural abnormality is suspected, ultrasound is usually the modality of choice for the initial evaluation. Ultrasound
is very sensitive for the detection of uterine myoma. With the
addition of sterile saline injected into the uterine cavity, the positive predictive value (PPV) for the detection of a submucosal
lesion is very high. Cepni et al. [10] found a PPV of 78% to 81%,
depending on menstrual status, for submucosal myoma using a
saline-infused sonogram (SIS). De Vries et al. [11] demonstrated
an increase in sensitivity in diagnosing intracavitary lesions from
regular vaginal sonogram to SIS from 60% to 88%. Using an SIS,
ultrasound can usually differentiate between polyps, myomas,
and carcinoma. Ultrasound can also be used to diagnose adenomyosis, although the sensitivity and specificity are not as high.
If the diagnosis is in doubt, MRI, although more costly, can better differentiate adenomyosis from other uterine pathology. In
addition, it is very useful in determining the size, number, and
location of uterine fibroids in preparation for surgery.
Three-dimensional sonography has shown some promise in
the diagnosis of submucosal myomas. Salim et al. [12] demonstrated a 75% to 95% specificity indeterminingthelevelofinvolvement in the myometrium. This could aid surgeons indetermining
whether a patient is a candidate for hysteroscopic resection.
Hysteroscopy is considered the gold standard for diagnosis.
It is redundant and adds unnecessary risks to take a patient to the
operating room simply todiagnose a submucosal myoma with no
immediate plans to resect it. However, the ability to perform inoffice, diagnostic hysteroscopy significantly decreases these risks.
is frequently usedas thedistending medium, and, with min-
CO
2
imal discomfort, a diagnosis can be made. Because of the significant effort, on the part of both the surgeon’s office and the
patient, to schedule a casefortheoperating room and perform the
preoperative evaluation required by many hospitals, an in-office
hysteroscopy may occasionally save much unnecessary effort and
lost time.
HSG was frequently used in the past to diagnose myomas.
Although it is still useful in infertility evaluation and often leads
to further work-up for myomas, it is not as sensitive or specific as
SIS. It isalso more invasive, with a higher risk of salpingitis/pelvic
inflammatory disease, so is no longer as commonly used to evaluate fibroids alone.
A hysteroscopic myomectomy is most likely to be performed
in cases of abnormal uterine bleeding or infertility. Although
myomas generally may cause a myriad of symptoms, unless the
myoma is causing abnormal bleeding or affecting fertility, a surgeon usually is not justified in performing a procedure that has
potential surgical and anesthetic complications. Performing a
hysteroscopic resection of a myoma will typically not resolve
symptoms related to the bulk of a uterus secondary to myomas.
Therefore, an appropriate work-up of abnormal uterine bleeding
and infertility is necessary before proceeding to surgery.
Abnormal uterine bleeding is a very common problem with a
great variety of causes. Before operating for asubmucosal myoma,
other causes of bleeding must first be explored. Anovulatory
bleeding is a common cause of abnormal uterine bleeding. It
is frequently found in the perimenarcheal and perimenopausal
age groups. Whereas fibroids are extremely unlikely in the former, they are very common in the latter. In fact, the period of
most rapid fibroid growth is often during the few years preceding menopause because of the hormonal changes that occur
around this time. Without the progestin withdrawal from ovulation, the continuously stimulated endometrium can randomly
bleed, occasionallyquiteexcessively.Womenwithpolycysticovarian syndrome also frequently have abnormal bleeding due to
anovulation. Not all submucosal myomas cause abnormal uterine bleeding. In addition, not all submucosal myomas require
surgical management. Hence, working up and medically treating other causes are prudent first steps before proceeding to
surgery. The complete evaluation for abnormal uterine bleeding
is beyond the scope of this section. Causes to assess, other than
structural ones, include bleeding disorders; hormonal causes,
such as anovulation; thyroid disease; hypothalamic dysfunction
from excessive weight loss, stress, and exercise; and foreign bodies, such as an IUD. Patients over 40 years of age or with a
history of untreated abnormal uterine bleeding for a period
greater than 1 year should have an endometrial biopsy to rule out
cancer.
Medical treatment for abnormal uterine bleeding, including
that caused by a submucosal myoma, should be considered. Oral
contraceptive use typically decreases blood loss during menses
by 50%.[13] Taking oral contraceptives in a continuous fashion frequently may stop menses altogether. Cyclic and continuous progestins may also be used in a similar fashion to decrease
menstruation. A progestin-containing IUD usually results in a
decrease in menstruation and frequently results in amenorrhea.
Unfortunately, however, abnormal bleeding caused by structural
defects such as submucosal myomas frequently do not respond
to medical therapy and require surgery.
Before gynecologists adopted the use of the resectoscope, the
vast majority of patients treated surgically for abnormal uterine bleeding proceeded to hysterectomy, usually via laparotomy.
They would besubjectedtoall the potential complications associated with this procedure, includingprolonged pain, longhospital
stay, and loss of work. The use of the resectoscope changed this
significantly for patients with abnormal bleeding due to a submucosal myoma. They are now able to have their problem dealt
with in an outpatient setting, with significantly less anesthesia
and decreased surgical risks. To maximize the chances of success
with the procedure, however, the patient and her uterus must be
optimized before the procedure.
The general principles of patient optimization beforesurgery
apply to patients who are undergoing resection of a submucosal
myoma. Significant anemia should becorrected if possible before
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proceeding to the operating room to decrease the intraoperative
risk of heart attack and stroke and to decrease the need for transfusion and its associated risks. Hormonal therapies such as oral
contraceptives and progestins alone may decrease the bleeding
enough so that the patient may increase her hemoglobin with
supplemental iron therapy alone. GnRH agonists are sometimes
necessary to stop the menstrual cycle altogether to enable the
woman to establish a surgically safe hemoglobin level.
Patients with concomitant medical conditions, such as diabetes or thyroid disease, should be maximally managed medically to decrease the risk of perioperative complications. Patients
should be well nourished, well rested, and relatively free of stress
when entering any surgical procedure.
The endometriumshould preferentially bein the early proliferative phase for any hysteroscopy. The endometrium is thinnest
at this point and less likely to hide small lesions. However, it
is not always possible to schedule this naturally. Because of the
availability of the surgeon and irregular menstrual cycles, it is
often necessary to manipulate the menstrual cycle, either with
oral contraceptives or progestins, to schedule the procedure with
the endometrium in the appropriate state. Prolonged progestin
treatment, as found in depomedroxyprogesterone acetate, frequently leads to endometrial atrophy, which allows for greater
visualization duringthe procedure.However,the effect is variable
and frequently outweighed by the side effects that may coincide
with this type of treatment, such as irregular bleeding, bloating,
weight gain, decreased libido, and headaches. Oral continuous
progestins, such as medroxyprogesterone acetate and norethindrone acetate, also may be used. Although they must be taken on
a daily basis, they have the benefit of being able to be stopped at
any time if the symptoms become unbearable for the patient.
Because the surgical removal of submucosal myomas is limited by the amount of distention fluid absorbed, it is especially
important for patients with larger myomas, who may take more
time to resect, to be optimally prepared for surgery. This frequently involves the use of GnRH agonists. After administration,
there is a brief period of stimulation over the first few days and
then a decrease in action of the hypothalamic–pituitary–ovarian
axis to a point of senescence. This results in a reversible pseudomenopausal statewithvery lowlevelsofbothcirculatingestrogens
and progestins. This has multiple effects on the patient and the
uterus specifically. First, itstops menstruation, which allows time
for the anemic patient to increase her hemoglobin.
GnRH agonists are best given just before the proliferative
phase, preferably from the middle to the end of menstruation.
During this period, the initial stimulation has less of a chance
to result in an increase in bleeding. If the GnRH agonist is used
later in the cycle, it should be given with 7 days of a concomitant progestin to stabilize the endometrium and inhibit further proliferation and potential bleeding secondary to the initial
stimulation.[14] If theagent is givenduring menses, bythe end of
the next cycle, the endometrium should be atrophic. If the agent
is given midcycle to late in the cycle, the surgeon needs to wait
until the completion of the following menstrual cycle.
In addition to thinning the endometrium, GnRH agonists
also haveothereffects in preparation for a hysteroscopicmyomectomy, such as causing myomas to shrink. Studies differ on the
amount, but the decrease is in the range of 30% to 50% by the
second to third month of treatment.[15,16] Most studies do not
demonstrate significantly more shrinking after the third month,
so using the medication for more than 3 months for this purpose
alone has little benefit. Shrinking the myoma should allow for a
quicker removal and therefore less time for absorption of distention media. In large myomas, it may make the difference between
completing the procedure in one step versus having to stage the
removal secondary to fluid and electrolyte risks.
GnRH agonists also cause a contraction of the uterine vessels
to approximately one half their initial diameter, which results in
decreased bleeding fromexposed vessels during resection. Therefore, less infusion of the distention fluid is required to clear the
blood. Perino et al. [17] demonstrated that by giving leuprolide acetate preoperatively to patients undergoing hysteroscopic
myomectomy, there was a significant decrease in operative time,
intraoperative bleeding, volume of distention fluid infused, and
persistence of fibroids 2 months postoperatively.
Patients should be warned about the potential side effects of
GnRH agonists before use. Most patients experience symptoms
similar to those felt in early menopause, including hot flushes
and vaginal dryness. Many have severe mood swings and changes
in weight. Rare problems such as bone pain may also occur, so
surgeons should not use the medication longer than is thought
necessary to best prepare the patient for surgery.
A few reports have been written on using suction curettage
as a way to optimize the cavity before hysteroscopy.[18,19] The
claimed advantage is decreased cost because time is saved and it
is easier to schedule the procedure, not just at the follicular stage;
there is less use of medications, therefore, less risk for ensuing
complications; and tissue from the entire cavity is sent for evaluation, not just tissuefromthefibroid.Casesofhyperplasia that are
not readily visually apparent would thereforenotbemissed. However, many of these patients will have had an endometrial biopsy
beforegoingtotheoperatingroom,decreasing thechance of missing other pathology. By curetting the cavity in a premenopausal
woman with the intention of removing the entire endometrium,
the risk for intrauterine adhesions that could affect fertility is
theoretically higher. In addition, by disrupting the entire cavity,
there is significantly more intrauterine bleeding, increasing the
amount of distention fluid to clear and the risk of fluid imbalance. Although it is helpful to have some data supporting this
technique when one finds oneself in the operating room with an
unprepared endometrium for whatever reason, it is not the ideal
method of uterine preparation for hysteroscopic myomectomy.
Cervical preparation can aid in the procedure as well. A postmenopausal and nulliparouswomanmay have a cervix thatis difficult to dilate. The use of preoperative laminaria or intravaginal
dinoprostone may help soften the cervix and allow for dilatation
appropriate for the resectoscope. Although it is rare for this to
actually be necessary for cervical dilatation, the less difficult the
surgeon finds each step of the procedure, the less likely he or she
is to experience any complications.
THE PROCEDURE
Although newer techniques are available for the resection of submucosal myomas, they are discussed in a later section. Here we
focus on the use of the resectoscope with a loop electrode.
The procedure begins with the selection of equipment. As
previously discussed, the resectoscope comes in different sizes
on the French (F) scale, the most common of which are 24F to
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