Ultrasound - Seeing with Sound
from the book How to Have a Baby:
by Dr. Aniruddha Malpani, MD and Dr. Anjali Malpani, MD.
table of contents
· previous page · next page
Ultrasound or sonography has helped revolutionize our approach to the
infertile patient. Ultrasound machines are the newest addition to the
gynecologist’s bag of tricks; and help him to "image" or see
structures in the female pelvis. Ultrasound uses high frequency sound waves much
like SONAR machines used in ships for detecting submarines underwater. The high
frequency sound waves are bounced off the pelvic organs; and the reflected sound
waves are received by the probe ( transducer) and a computer is used to
reconstruct the waves into black and white images on the monitor. Ultrasound
machines today are all real-time machines, which give dynamic images.
In the old days, ultrasound for infertility was done through the abdomen.
This required you to fill up your bladder ( till it was ready to burst !) so
that the sound waves could be transmitted into the pelvis. However, the standard
ultrasound technique today for infertility is vaginal ultrasound ( endovaginal
scanning) in which a long, slim, slender probe is inserted into the vagina and
used for imaging the pelvic organs. Not only is this much more comfortable for
you; it also gives much sharper and clearer pictures, since the probe is much
closer to the pelvic structures.
What can you see on ultrasound? The ultrasound gives clear pictures of the
uterus; and the ovaries. It allows the doctor to look for fibroids; ovarian
cysts; and ectopic pregnancies. It is also excellent for early diagnosis of
pregnancies. However, the ultrasound scan is not very good for assessing whether
or not the tubes are normal.
Ovulation scans allow the doctor to determine accurately when the egg
matures; and when you ovulate. This is often the basic procedure for most
infertility treatment since the treatment revolves around the wife's ovulation.
Daily scans are done to visualize the growing follicle, which looks like a black
bubble on the screen. Most women can see the follicle clearly for themselves -
and know by the scans when the egg has ruptured. Other useful information which
can be determined by these scans is the thickness of the uterine lining - the
endometrium. The ripening follicle produces increasing quantities of estrogen,
which cause the endometrium to thicken. The doctor can get a good idea of how
much estrogen you are producing (and thus the quality of the egg) based on the
thickness and brightness of the endometrium on the ultrasound scan.
Fig 1. Ultrasound scan showing multiple follicles
Ultrasound scan of the uterus, showing a normal endometrium, which
appears as a triple band in the center of the uterus
One of the commonest findings on an ultrasound scan is an ovarian cyst. A
cyst is a collection of fluid surrounded by a thin wall (a fluid-filled sac)
that develops in the ovary. Typically, ovarian cysts are functional (not
disease-related) and disappear on their own. During ovulation, a follicle may
grow , but fail to rupture and release an egg. Instead of being reabsorbed, the
fluid within the follicle persists and forms a follicular cyst. The other type
of functional cyst is a corpus luteum cyst, which develops when the corpus
luteum fills with blood. Functional ovarian cysts usually resolve on their own,
and are not to be confused with other pathological conditions involving cystic
ovaries, specifically polycystic ovarian disease, endometriotic cysts, or
ovarian tumours. Since an ultrasound picture is just a black and white shadow,
the doctor has to be skillful in interpreting what the image means. Simple cysts
are thin walled, and appear as a large black bubble. Cysts which contain blood (
for example, chocolate cysts found in patients with endometriosis) will have
echoes within them, which appear white, and these are described as complex
masses on ultrasound. The incidence of follicular cysts is increased in
infertile patients taking drugs (such as clomiphene and HMG) for ovulation
induction. Functional ovarian cysts usually disappear within 60 days without
treatment. However, if the cyst is larger than 6 cm, or persists for longer than
6 weeks, then further testing may be needed.
Who does the scans? Ultrasound scans can be done either by a radiologist; or
by the gynecologist or infertility specialist himself. Remember that the eye
only sees what the mind knows, so you must go to a good clinic for your scans.
The benefit of having the scans done by the infertility specialist himself is
that he can make immediate decisions regarding your treatment based on the scan
findings. If the radiologist does the scans, then you have to wait till your
doctor has seen the report before knowing what to do next since the radiologist
does not make the treatment decisions. In any case, it is vital that the
ultrasound scans be done in the Infertility Clinic itself, so that your waiting
can be minimized - and you don't have to run around from the sonographer to the
gynecologist. If there are any abnormal findings, it is vital that your
gynecologist see the actual ultrasound for himself during the scan. This
provides much more information than the printed pictures.
Recent Advances in Ultrasound
Ultrasound technology has made dramatic advances in recent years, and now
tests have been described which allow the doctor to use ultrasound to assess
tubal patency. Basically, these involve passing a fluid into your tubes through
the uterus; and the gynecologist can see the passage of the bubbles into the
tubes and out into the abdomen. Since this test (sonosalpingography) can be
done in the doctor's clinic itself, and does not involve X-ray radiation, it has
advantages - especially for documenting that the tubes are normal. However, the
gold standard for tubal testing remains HSG and laparoscopy today.
Doppler: The newer ultrasound machines have Doppler attachments which allow
the doctor to judge the flow of blood in the blood vessels. The most exciting
advance is that of Colour Doppler, where the blood flow can be mapped in color
on the monitor. While still a research tool, it may provide important
information for assessing the infertile patient in the coming years.
Three – dimensional ultrasound. Using sophisticated microprocessors, the
newest ultrasound machines allow the doctor to reconstruct the image, so that he
gets a three dimensional view. While this provides excellent pictures, the true
value of this technique for infertility still has to be evaluated.
Ultrasound now also offers infertile patients newer treatment options not
available before. Modern surgical techniques have progressively become less and
less invasive - all to the patient's benefit! From laparotomy to laparoscopy,
and now to ultrasound guided procedures, we are witnessing a change in the
gynecologist's armamentarium from the knife to the endoscope to the guided
The benefits to the patient are many and include : reduced costs; reduced
hospitalisation ; reduced risk of complications; and better preservation of
fertility, with increased chance of conception for the future.
Ultrasound-guided procedures can be used to treat a variety of problems seen
in the infertile woman.
- Egg pickup for IVF - The use of vaginal ultrasound for egg pickup has made
egg retrieval a short, simple and inexpensive procedure, which can be performed
in a day-care unit, under sedation and local anesthesia . The ovaries are
normally present in the pouch of Douglas, and are very accessible transvaginally.
Moreover, the presence of adhesions does not interfere with egg collection.
- Ovarian cyst aspiration. An ovarian cyst is a very common condition in
which fluid collects in the ovary. However, cysts which are more than 5 cm in
size need to be treated, as they can cause problems (e.g., twisting and rupture).
Normally, surgery had to be done to remove these cysts - and often this damaged
the surrounding normal ovary as well. With ultrasound-guidance, we can stick a
needle from the vagina into the cyst, and empty the contents ( usually clear
fluid ) by sucking it out. This empties the cyst, which often does not recur.
- Treatment of ectopic pregnancy . With technological advances (ultrasound
and beta-HCG blood tests) the diagnosis of tubal pregnancy can be made very
early, usually before rupture. It can be treated by injecting a toxic chemical,
methotrexate, into the sac, which causes the tissue to die and then get
reabsorbed, without any surgery whatsoever. In more advanced tubal pregnancies,
potassium chloride can be injected direct into the heart of the baby in the
ectopic gestational sac, thus killing it and preventing it from growing.
- Ultrasound-guided tubal embryo and gamete transfer for IVF and GIFT
techniques. Techniques have been devised to pass a special tube - the
Jansen-Anderson catheter set - into the fallopian tubes through the vagina under
ultrasound guidance, so as to place the embryos and /or the gametes in the
fallopian tube. Since the tube offers a better environment for the gametes and
embryos than the uterine cavity, it is believed that this will improve pregnancy
- Tubal recanalisation for cornual blocks (proximal tubal obstruction) .
Often cornual blocks are due to the presence of mucus plugs and amorphous debris
in the tubal lumen. Ultrasound guided tubal catheterization can effectively
treat the blocked tubes in some of these patients.
The scope of ultrasound guided procedures has increased dramatically in the
last few years; and with further improvements in technology, we can expect this
list to become even longer, and doctors become more versatile with using this
by Dr. Aniruddha Malpani, MD and Dr. Anjali Malpani, MD.
previous page · next page
Copyright 2001-2017 Internet