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Ultrasound uses high frequency sound waves that bounce off internal tissues and produce echoes. These echo patterns are shown on the screen of the ultrasound machine forming a picture of the body tissue being examined.

These studies are performed by registered medical sonographers and radiologists.

There are no known harmful effects to adults, children or unborn babies.
The reason for the examination will depend on your condition or symptoms. Some specific ultrasound exams include:

  • Abdominal ultrasound
  • Pregnancy ultrasound
  • Vascular ultrasound
  • Thyroid ultrasound
  • Trans-vaginal ultrasound
  • Prostate ultrasound
  • Testicle ultrasound
  • Extremity ultrasound

Contact Information

To book or follow up on the status of your appointment, please contact:

Mississauga Hospital or Queensway Health Centre
Phone: 416-521-4069
Fax: 416-521-4014

Credit Valley Hospital:
Phone: 905-813-2731
Fax: 905-813-4418


A referral from a doctor is required.

Resources for Patients & Their Families

How to Prepare for Your Procedure

Preparing for General Abdomen Ultrasound (Gallbladder, Liver, Pancreas, Spleen, Kidney and Aorta):

Adults: Please allow a minimum of 45 minutes for your appointment.
Do not eat or drink anything for 12 hours before your appointment.
Avoid gas producing foods such as beans and carbonated beverages for 24 hours before your examination.

There will be less gas if you refrain from smoking and chewing gum for 12 hours.
Patients on medication may take it with a small amount of water.
Insulin dependant diabetics should take their insulin with dry toast and juice the morning of their examination.

Children 12 years and under: do not eat or drink for 4 hours prior to the examination time.
Infants: stop feeding 2 hours prior to examination time.

Preparing for Kidney and Bladder Ultrasound Only:
Please allow a minimum of 30minutes for your appointment.

  • Your bladder should be full.
  • Please do not empty your bladder for 3 hours prior to your appointment time.
  • You do not need to drink extra water and you may eat.

Preparing for Obstetrical and Pelvis Ultrasound:

  • Please allow a minimum of 1 hour for your appointment.
  • Your bladder must be full. Please finish drinking 3 – 4 large glasses of water or clear fluids 1 hour before your appointment time to allow time for your bladder to fill.
  • You may eat.

Preparing for Thyroid, Neck, Testicles, Extremities Ultrasound:

  • Please allow a minimum of 30 minutes for your appointment.
  • No preparation necessary.

What to Expect from Your Procedure

There is generally little discomfort with ultrasound procedures. The conducting gel may feel slightly cold and wet.

The test is done in the ultrasound department. You will be lying down for the procedure. A clear, water-based conducting gel is applied to the skin over the area being examined to help with the transmission of the sound waves. A handheld probe called a transducer is then moved over the area being examined. You may be asked to change position so that other areas can be examined.

How It Works

An ultrasound machine creates images that allow various organs in the body to be examined. The machine sends out high-frequency sound waves, which reflect off body structures. A computer receives these reflected waves and uses them to create a picture. Unlike with an x-ray, there is no ionizing radiation exposure with this test.

Most ultrasound examinations are performed in the manner described. However, certain circumstances require that the ultrasound probe be inserted into the body, rather than simply passing it over the skin. Consult your health care provider to determine the specifics of your test.