Frequently Asked Questions Regarding Ultrasound
What is an ultrasound?
Ultrasound uses high frequency sound waves to produce images. Sound waves are sent and received through a small hand held device known as a transducer. The returning sound waves are used to produce the images. In experienced hands, it is a highly accurate technique, which can be used to diagnose a large variety of soft tissue abnormalities.
Why has my doctor ordered an ultrasound?
Ultrasound serves as a focused examination of a specific body part or group of organs and can complement other imaging techniques such as computed tomography (CT) or magnetic resonance imaging (MRI). It can even provide information that cannot be gleaned from these other techniques. You may be familiar with the role of ultrasound during pregnancy, or to examine your gallbladder or kidneys. You may also be familiar with the term Doppler imaging, which is an ultrasound technique that provides blood flow information in arteries and veins.
In addition to the use of ultrasound for diagnosis, it can be used to guide certain procedures such as thyroid biopsy, lymph node biopsy, or removal of fluid from a joint. Because ultrasound images are in "real-time," your doctor may ask us to use ultrasound to help perform procedures, such as withdrawing fluid from a joint or for the injection of medication into a joint or mass. Ultrasound allows the radiologist to continuously monitor "realtime" the position of a needle in a joint, bursa, cyst, soft tissue mass, etc..., and monitor the progress of an aspiration or injection.
Who performs and interprets ultrasound?
The ultrasound examination will be performed either by a technologist, who has received training by an accredited institution to perform ultrasound examinations, or by an ultrasound experienced radiologist. Because ultrasound is operator dependent, it will often be the case that the examination will first be performed by the technologist and the radiologist may come in to post-scan, to further define an area of interest and ensure that the best possible examination is obtained. The radiologist is the one who renders the final interpretation of the study.
How is the ultrasound performed?
The individual being examined is either seated comfortably in a chair, or lies on a stretcher. Depending on the area to be examined, it may be necessary for you to wear a gown or to assume a particular position, to allow access to the area of concern. A clear gel is applied to the area being examined. The ultrasound transducer is placed directly on the gel to produce images.
What should I do to prepare for the ultrasound?
In most instances, no particular preparation is required. Depending on the area being examined, some initial preparation may be necessary. When looking at the gallbladder, several hours of fasting prior to the exam is required, or when looking at the pelvic organs, it will be necessary to drink water to fill up the bladder. The necessary information will be provided to you at the time the specific exam is scheduled.
What are the risks?
Ultrasound involves no radiation and is extremely safe. You may be familiar with the role of ultrasound when it has been used to study the fetus in all phases of development.
What are the alternatives?
Other imaging modalities such as CT or MRI may provide similar types of information or complementary information. When ultrasound is appropriate, it also has the advantage of providing comparable or unique information.
What can I expect after the ultrasound examination?
Following an ultrasound examination performed only for diagnostic purposes, you will be able to immediately resume your pre-examination activities. If a procedure (such as a biopsy) is performed utilizing ultrasound guidance, in most cases you will be able to resume regular activities within a day.