Ultrasound

About the Procedure

Ultrasound is a technology using sound waves directed at an object of interest and, as the waves meet obstacles blocking their penetration, they are reflected backwards where a computer program translates them into images. These "echoes" are reflected at different times and speeds, depending on the density of the material being scanned, creating images in a range of white to grey to black shades. In the medical field, ultrasound is utilized to scan areas of soft tissue and is routinely suggested for abdominal and cardiac areas. Other parts of the body that benefit from ultrasound imaging are the skeleton, eyes, glands, testicles, teeth, and it is sometimes used in conjunction with biopsies and fine needle aspirations for diagnostic purposes. Ultrasound is invaluable for its application in trauma and first aid and for its use in remote diagnosis, such as in outer space. In addition to diagnosis, ultrasound has a therapeutic use, e.g., breaking up kidney and gall stones, for destruction of abnormal cells, and treatment of cataracts.

The procedure, performed by a sonographer, is painless and non-invasive, and takes 30 - 60 minutes. The sonographer identifies the optimum position for scanning the area of interest and the patient is made as comfortable as possible. A warm gel is squeezed onto the skin and the transducer, a microphone-like instrument which both emits and receives sound waves, uses the gel to move around the body capturing echoes. If a Doppler device is used, whooshing sounds can be heard as it records the flow of blood which it picks up from reflected sound waves. When the procedure is complete, the sonographer wipes the gel from the patient's skin and they may leave.

What to Know Before the Procedure

There are differing opinions in the medical communities regarding the risks of ultrasound. Some feel that caution and good judgment, guided by professional standards, reduce the potential for short or long term damage. Others cite studies on animals which show that admittedly excessive dosages of sound waves have caused severe damage. There are two known physiological effects of this technology. It enhances inflammatory response and it can heat soft tissue and cause distortion within the cell. Currently proponents believe the level of ultrasound units being used today is too low to cause severe reactions. It is important to recognize the limitations of ultrasound. Sound waves are not effective when there is considerable air and gas in the area scanned and it is not effective penetrating bone which makes scanning soft tissues around or behind bones difficult. Despite these concerns, it is considered a safe procedure and is valued as a non-radiation alternative.

An ultrasound scan does not require a lot of preparation. Abdominal scans may require food and fluid restrictions; bladder and obstetrical scans may require drinking water prior to the procedure; and prostate tests require a Fleet enema, among others depending on the area to be scanned. The physician will advise the patient prior to the day of the procedure regarding specific preparations.

What to Know After the Procedure

After a simple ultrasound, patients can leave the facility on their own and return to normal activities immediately. Patients with more complex procedures will be monitored for a period of time before discharge.

A radiologist prepares a report on his/her findings and sends it to the patient's physician. This report and the images may be available through an internal network or the Internet which allows the referring doctor and the patient to view them. A follow-up conversation between patient and doctor will involve treatment plans, medication, and/or surgery, as necessary.

If you Need to Travel Outside of your Local Hospital

Based on the available information, there is no reason to restrict travelling for this procedure. There is no recovery period or risk of complications, and with electronic transmission of information, ultrasounds done in one location can easily and quickly be sent to a local primary doctor. Consideration should be given to weighing the costs of time and travel against any cost-saving benefits.