In this Section:
What is Ultrasound Imaging?
Ultrasound imaging, also called ultrasound scanning or sonography, involves exposing part of the body to high-frequency sound waves to produce pictures of the inside of the body. Ultrasound exams do not use ionizing radiation (as used in x-rays). Because ultrasound images are captured in real-time, they can show the structure and movement of the body's internal organs, as well as blood flowing through blood vessels.Doppler ultrasound is a special ultrasound technique that evaluates blood velocity as it flows through a blood vessel, including the body's major arteries and veins in the abdomen, arms, legs and neck.
How should I prepare?
This examination is done on an outpatient basis, and an appointment is necessary. Please arrive 15 minutes prior to your appointment to register. If you are late for your appointment you will be rebooked.
You must bring a valid health card and requisition.
Please call ahead if you have had a barium enema or a series of upper GI (gastrointestinal) tests within the past two days. Barium that remains in the intestines can interfere with the ultrasound test.
You should wear comfortable, loose-fitting clothing for your ultrasound exam. You may need to remove all clothing and jewelry in the area to be examined. You may be asked to wear a gown during the procedure.
Specific preparations include:
- Obstetrical/Pelvic/Renal – These examinations require a full bladder. Do not empty your bladder for 2 hours prior to the appointment. Finish 1 liter of water 1 hour prior to the appointment.
- Abdomen – Do not eat or drink for 8 hours prior to the appointment. Medications can be taken with sips or water. In particular, do not drink carbonated beverages or chew gum for 8 hours prior to the appointment.
How is the procedure performed?
The technologist, an individual specially trained to perform ultrasound examinations, will bring the patient into the room, verify the information, obtain a brief history, and perform the examination. The patient will be asked to lie on a padded table. For most ultrasound exams, the patient is positioned lying face-up on an examination table that can be tilted or moved. A clear water-based gel is applied to the area of the body being studied to help the transducer make secure contact with the body and eliminate air pockets between the transducer and the skin. The sonographer (ultrasound technologist) or radiologist then presses the transducer firmly against the skin and sweeps it over the area of interest. The patient may be asked to stop breathing or change position during the examination.
Doppler sonography is performed using the same transducer.
Sometimes the radiologist determines that a transvaginal scan needs to be performed. This technique often provides improved, more detailed images of the uterus and ovaries. This method of scanning is especially useful in early pregnancy. Transvaginal ultrasound is performed very much like a gynecologic exam and involves the insertion of the transducer into the vagina after the patient empties her bladder. The tip of the transducer is smaller than the standard speculum used when performing a Pap test. A protective cover is placed over the transducer, lubricated with a small amount of gel, and then inserted into the vagina. Only two to three inches of the transducer end are inserted into the vagina. The images are obtained from different orientations to get the best views of the uterus and ovaries. Transvaginal ultrasound is usually performed with the patient lying on her back, possibly with her feet in stirrups similar to a gynecologic exam.
When the examination is complete, the patient may be asked to dress and wait while the ultrasound images are reviewed. However, the sonographer or radiologist is often able to review the ultrasound images in real-time as they are acquired and the patient can be released immediately. This ultrasound examination is usually completed within 30 minutes.
A radiologist, a physician specifically trained to supervise and interpret radiology examinations, will analyze the images and send a signed report to your referring physician, who will discuss the results with you.