Naples Ultrasound
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 (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.
Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. A Doppler ultrasound study may be part of an ultrasound examination. 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 does the procedure work?
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 and its size, shape, and consistency.
Doppler ultrasound, a special application of ultrasound, 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 color pictures that represent the flow of blood through the blood vessels.
How is the procedure performed?
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) then presses the transducer firmly against the skin and sweeps it over the area of interest. If scanning is performed over an area of tenderness, you may feel pressure or minor pain from the transducer. 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.
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 and you should be able to resume your normal activities. In some ultrasound studies, the transducer is attached to a probe and inserted into a natural opening in the body. These exams include:
- Transrectal ultrasound. The transducer is inserted into a man's rectum to view the prostate.
- Transvaginal ultrasound. The transducer is inserted into a woman's vagina to view the uterus and ovaries.
Most ultrasound examinations are completed within 30 minutes to an hour.
Who interprets the results and how do I get them?
A radiologist, a physician specifically trained to supervise and interpret radiology examinations, will analyze the images and send a signed report to your primary care physician or the physician who referred you for the exam, who will share the results with you. In some cases the radiologist may discuss results with you at the conclusion of your examination.
What are the limitations of Ultrasound Imaging?
Ultrasound waves are disrupted by air or gas; therefore ultrasound is not an ideal imaging technique for the bowel or organs obscured by the bowel. In most cases, barium exams, CT scanning, and MRI are the methods of choice in this setting. Large patients are more difficult to image because tissue attenuates (weakens) the sound waves as they pass deeper into the body. Ultrasound has difficulty penetrating bone and therefore can only see the outer surface of bony structures and not what lies within. For visualizing internal structure of bones or certain joints, other imaging modalities such as MRI are typically used.