Ultrasound is a safe and widely used imaging technique.
An ultrasound of the female pelvis may be performed by examination of the abdomen, called transabdominal, or by using a special probe designed to be inserted into the vagina, called transvaginal. The type of examination you will need will depend on what your referring doctor has requested and the nature of the clinical condition being investigated.
Obstetric gynaecological ultrasound is safe and painless. It produces pictures of the inside of the body using sound waves. Ultrasound imaging is also called ultrasound scanning or sonography. It uses a small probe called a transducer and gel placed directly on the skin.
High-frequency sound waves travel from the probe through the gel into the body. The probe collects the sounds that bounce back. A computer uses those sound waves to create an image.
Ultrasound exams do not use radiation (as used in x-rays). As images are captured in real-time, they can show the structure and movement of the body’s internal organs. They can also show blood flowing through blood vessels.
Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions.
Obstetrical gynaecological ultrasound provides pictures of an embryo or fetus within a woman’s uterus, as well as the mother’s uterus and ovaries. A Doppler ultrasound study may be part of an obstetrical ultrasound examination.
Doppler ultrasound is a special ultrasound technique that evaluates movement of materials in the body. It allows the doctor to see and evaluate blood flow through arteries and veins in the body.
During an obstetrical ultrasound the examiner may evaluate blood flow in the umbilical cord or may, in some cases, assess blood flow in the foetus or placenta.
You should wear a loose-fitting, two-piece outfit for the examination. Only the lower abdominal area needs to be exposed during this procedure.
The radiologist or sonographer may elect to examine an early pregnancy by means of transvaginal ultrasound in order to see the pregnancy more closely or to assess the cervix.
Obstetric gynaecological ultrasound imaging is based on the same principles involved in the sonar used by bats, ships and fishermen. When a sound wave strikes an object, it bounces back, or echoes. By measuring these echo waves, it is possible to determine how far away the object is as well as the object’s size, shape and consistency. This includes whether the object is solid or filled with fluid.
In medicine, ultrasound is used to detect changes in the appearance of organs, tissues, and vessels and to detect abnormal masses, such as tumors.
In an ultrasound exam, a transducer both sends the sound waves and records the echoing waves. When the transducer is pressed against the skin, it sends small pulses of inaudible, high-frequency sound waves into the body.
As the sound waves bounce off internal organs, fluids and tissues, the sensitive receiver in the transducer records tiny changes in the sound’s pitch and direction. These signature waves are instantly measured and displayed by a computer, which in turn creates a real-time picture on the monitor.
One or more frames of the moving pictures are typically captured as still images. Short video loops of the images may also be saved.
The movement of the embryo or foetus and his or her heartbeat can be seen as an ongoing ultrasound movie. Ultrasound devices also use Doppler, a special application of ultrasound, which processes echoes produced by blood flowing through the fetal heart, blood vessels and umbilical cord and turns them into audible sound. This sound has been described by patients as a whooshing noise.
Doppler ultrasound, a special ultrasound technique, measures the direction and speed of blood cells as they move through vessels. The movement of blood cells causes a change in pitch of the reflected sound waves (called the Doppler effect). A computer collects and processes the sounds and creates graphs or colour pictures that represent the flow of blood through the blood vessels.
Most obstetric gynaecological ultrasound exams are painless, fast and easily tolerated.
However, at times during an obstetrical ultrasound, the sonographer may have to press more firmly to get closer to the embryo or foetus to better visualize the structures. Any discomfort is usually minimal and temporary.
If a Doppler ultrasound study is performed, you may actually hear pulse-like sounds that change in pitch as the blood flow is monitored and measured.
With transvaginal scanning, there may be minimal discomfort as the transducer is inserted into the vagina.
This ultrasound examination is usually completed within 30 minutes.
When the exam is complete, you may be asked to dress and wait while the ultrasound images are reviewed.
After an ultrasound examination, you should be able to resume your normal activities immediately.