Ultrasound imaging is also called ultrasound
scanning or sonography. It involves exposing part of the
body to high-frequency sound waves to produce pictures
of the internal organs of the body. Some organs are
situated deep inside the abdominal or pelvic cavity.
Ovaries, for example, are not easily palpable. An
ultrasound of the ovaries helps in accurate diagnosis of
ovarian problems. Ultrasound exams do not use ionizing
radiation as in x-rays. The ultrasound images are
captured in real-time and can show the structure and
movement of the body's internal organs, as well as blood
flowing through blood vessels. This type of imaging is
noninvasive and helps physicians diagnose and treat
medical conditions.
The
primary indications for a pelvic ultrasound are
pelvic masses, pelvic pain, and abnormal bleeding. Views
of the pelvis are obtained trans-abdominally through a
full urinary bladder and trans-vaginally through an
empty urinary bladder.
There is a
considerable range of normal ovarian size between birth
and two years of age because of the presence of cysts
and follicles, which is normal and the follicles are
normally less than 5 mm in diameter. The ovaries
increase in size up to puberty and a multicystic
appearance is fairly common. After menarche, the ovaries
become ovoid in shape and the normal ovarian volume is 5
ml to 15 ml. Ovaries decrease in size after menopause.
Due to their small size and lack of follicles,
postmenopausal ovaries are difficult to visualize.
Ovarian
cysts are common in all age groups. Typical benign cysts
are completely anechoic, have thin walls, no septations,
and no solid elements. Hemorrhagic cysts have a more
complex appearance with internal septations and a
retractile clot. If a lesion has questionable
appearance, or is larger than 3 cm, serial scans are
necessary. Typically, most ovarian cysts show
resolution. A variety of non-ovarian tumors and other
abnormalities can be mistaken for solid ovarian masses.
The diagnosis of an ovarian abnormality depends upon
patient's age, time since last menstrual period,
hormonal status, symptoms, prior surgery, and physical
examination findings. Functional cysts and benign tumors
are more common in women of reproductive age. Malignant
lesions are more common in postmenopausal women.
However, ultrasound of
ovaries is of limited value as the only method of
detection of early stages of ovarian cancer and needs to
be combined with serum cancer marker tests such as
CA125.
The
benefits of ultrasound can be listed
as:
- Most
ultrasound scanning is noninvasive and
painless.
- Widely
available and less expensive than other imaging
methods.
- Ultrasound
imaging uses no ionizing
radiation.
- Ultrasound
scanning gives a clear picture of soft tissues that do
not show up well on x-ray
images.
- Ultrasound
may be repeated as often as is necessary.
- Ultrasound
is the preferred for monitoring pregnancy and
fetus.
- Ultrasound helps identify and evaluate a variety of genitor-urinary disorders in both sexes without even the minimal risks associated with x-rays.
