from the book How to Have a Baby: Overcoming
Infertility
by Dr. Aniruddha Malpani, MD and Dr. Anjali Malpani,
MD.
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Hysteroscopy (Page 2)
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Tubal Connection (Page 2)
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What
are the fallopian tubes ?
How
is tubal disease diagnosed ?
What
are the recent innovations for tubal factor diagnosis
and treatment ?
What
are the fallopian tubes ?
The fallopian tubes project out from
each side of the body of the uterus and form the passages
through which the egg is conducted from the ovary into
the uterus. The fallopian tubes are about 10 cms long
and the outer end of each tube is funnel shaped, ending
in long fringes called fimbriae. The fimbriae catch
the mature egg and channel it down into the fallopian
tube when released by the ovary .
The tube itself is a muscular highly
movable structure capable of highly coordinated movement.
The egg and sperm meet in the outer half of the fallopian
tube, called the ampulla. Fertilization occurs here,
after which the embryo continues down the tube toward
the uterus. The uterine end of the tube, called the
isthmus, acts like a sphincter, and prevents the embryo
from being released into the uterus until just the right
time for implantation, which is about 4 to 7 days after
ovulation.
The tube is much more complex than a
simple pipe, and the lining of the tube is folded and
lined with microscopic hair like projections called
cilia which push the egg and embryo along the tube.
The tubal lining also produces a fluid that nourishes
the egg and embryo during their journey in the tube.
Fig 1. Normal tube and ovary, as seen during laparoscopy
Tubal abnormalities account for between 25% and 50%
of female infertility .Tubal damage usually occurs through
pelvic infection , and this is called pelvic inflammatory
disease ( PID). Often, we cannot find out the cause
for the inflammation. However, some of the causes of
pelvic infection that can be pinpointed are :
- Sexually transmitted diseases (e.g.
Gonorrhea, Chlamydia)
- Infection after childbirth, miscarriage,
termination of pregnancy ( MTP) or IUD (intrauterine
device) insertion
- Post-operative pelvic infection (e.g.
perforated appendix, ovarian cysts)
- Severe endometriosis
- Tuberculosis
Besides causing blocked tubes, any pelvic
inflammatory disease can also produce bands of scar
tissue called adhesions, which can alter the functioning
of the fallopian tubes. PID can be a silent disease,
and most women with tubal damage because of PID are
completely unaware that they have this disease.
Pelvic tuberculosis is a fairly common
cause of tubal damage in India. The tuberculosis bacteria
reach the tubes from the lungs through the bloodstream
and can cause irreparable tubal damage.
How
is tubal disease diagnosed ?
A number of tests are available to judge whether or
not the tubes are open.
The simplest and oldest test for tubal
patency is the RT or Rubin's test named after its inventor.
In this test, gas is passed under pressure into the
tubes through the cervix and uterus - either with a
special machine (Rubin's apparatus) or with an ordinary
syringe. The doctor then listens with a stethoscope
placed on the abdomen to determine if he can hear the
sound of gas passing through the fallopian tube. Even
though this test is now obsolete, because it is so unreliable,
a number of doctors still do it.
Blood tests for chlamydial antibodies:
Since an infection with chlamydia is the commonest reason
for tubal disease in the West, some doctors test the
blood for antibodies against chlamydia . Women who have
antibodies against chlamydia have been exposed to this
infection in the past, and are considered to be at higher
risk for tubal damage.
Hysterosalpingogram (Uterotubogram)
or HSG is a specialized X-ray of the uterus and tubes.
An HSG is done after the menstrual flow has just stopped
- usually on Day 6 or 7 of the period, at which time
the lining of the uterus is thin. It is done in an X-ray
Clinic. The patient is advised to take an antibiotic
and a pain-killer before the procedure by many doctors.
After being positioned on the X-ray table, the doctor
places a special instrument into the cervix, called
a cervical cannula, which is made of metal. Many doctors
now prefer to use a balloon catheter , as this makes
the procedure less painful. A radio-opaque dye (a liquid
which is opaque to X-rays) is then injected into the
uterine cavity. This is done slowly under pressure,
and pictures are taken - preferably under an image intensifier.
The passage of the dye into the uterine cavity and then
into the tubes and from there into the abdomen can be
seen; and X-ray pictures taken. These provide a permanent
record.
At least 3 films need to be taken to
provide a reliable record - including an early film
for the uterine cavity; and a delayed film to make sure
the spill in the abdomen is free.
A normal HSG defines the inside of the
reproductive tract. This appears as a triangle (usually
white on a black background) which represents the uterine
cavity; and from here the dye enters the tubes which
appear as two long thin lines, one on either side of
the cavity. When the dye spills into the abdomen from
a patent ( open) tube, this appears as a smudge in the
X-rays.
Fig 2. Normal HSG findings ( the dye appears black and
outlines a normal cavity and fallopian tubes)
An abnormal HSG may show a problem in
the uterine cavity - and this appears as a gap or filling
defect. However, the commonest problems on HSG appear
in the tubes. If the tubes are blocked at the cornual
end (at the uterotubal junction), then no dye enters
the tubes and they cannot be seen at all. If the block
is at the fimbrial end then the tubes fill up; but the
dye does not spill out into the abdominal cavity and
the end of the tubes are often swollen up.
Sometimes, like any other medical test,
the HSG may provide erroneous results. For example,
the cornu of the uterus may go into spasm, as a result
of which the dye may not enter the tubes at all. This
may be interpreted as a tubal block, whereas in reality
the tubes are open. Also, if a hydrosalpinx is very
thin and if the dye is injected under pressure, the
dye may appear to spill into the abdomen through a tear
in the wall of the hydrosalpinx - suggesting tubal patency
when really the tubes are closed.
While the HSG is usually very reliable
for determining whether or not the tubes are open, it
provides little information on structures outside the
tube which could nevertheless impair tubal function
- such as peritubal adhesions. If the spill is "loculated",(i.e.
it collects in small puddles), the presence of adhesions
can be suspected, but not confirmed.
An HSG can be painful - and when the
dye is injected into the uterine cavity, most women
will experience a considerable amount of pain. You should
be prepared for this - and taking a pain-killer prior
to the procedure will help to reduce the pain.
An HSG can be technically difficult
for some women (especially if the cervix is too small
or too tight) - and it is better if a gynecologist is
present at the time of the HSG to assist the radiologist
if needed. Many gynecologists will do the HSG themselves.
The major risk of an HSG is that of
spreading an unrecognized infection from the cervix
up into the tubes. This is uncommon, but in order to
reduce the risk, many doctors advise antibiotic coverage
during the procedure.
If the HSG shows that the tubes are
closed, then it may be advisable to repeat the HSG;
and also to do a laparoscopy to confirm this diagnosis.
Laparoscopy. This has already been described,
and is the gold standard for making a diagnosis of tubal
disease.
The trouble with both HSG and laparoscopy is that they
only provide information as to whether or not the tube
is open or closed. While a closed tube will never work,
they do not provide any information on how well an apparently
open tube works. Remember, that just because a tube
is patent does not necessarily mean that it works!
Fig 3. Laparoscopy shows a large hydrosalpinx on the
right side
Another limitation is that they will
rarely provide any information as to why the tubes are
blocked. Occasionally, however, this can be suspected
by other signs (for example, by seeing the tubercles
diagnostic of TB in the abdomen during laparoscopy).
What
are the recent innovations for tubal factor diagnosis
and treatment ?
Fluoroscopic guided procedures: Using an image
intensifier, and techniques borrowed from coronary angioplasty,
the radiologists can now insert special catheters under
fluoroscopic guidance into each of the tubes. This is
called selective salpingography; and allows much better
visualization of each tube. It also allows the radiologist
to treat cornual blocks which are due to mucus plugs
by tubal cannulation.
Sonosalpingography: Under ultrasound
guidance, with Doppler facilities if available, the
gynecologist can inject fluid into the tubes through
the cervix and see the flow of the fluid into the tubes
and abdomen on the ultrasound screen. This is a simple
bedside test which a gynecologist can do to judge if
the tubes are normal - and can be reassuring if positive.
Tuboscopy: At the time of laparoscopy,
the doctor can insert a fine telescope into the fallopian
tube through its fimbrial end, to inspect the inner
lining of the tube, to judge whether or not it is healthy.
Falloposcopy is a recent advance,
pioneered by Dr Kerin of USA. In this method, a very
fine flexible fiberoptic tube is guided through the
cervix and uterus into each fallopian tube, thus allowing
the doctor to actually visualize the inner lining of
the entire length of the fallopian tube - something
which was never possible so far. This can provide useful
information about the extent of tubal damage, and the
possibility for successful repair.
continued
. . .
Next page: The
Tubal Connection (Page 2)
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