What is Ultrasound and how does it work?

Ultrasound or ultrasonography is a non-invasive diagnostic medical imaging technique that uses high frequency sound waves to produce images (sonogram) of the internal structures of the body. Frequencies above 20,000 Hz are called ultrasonic and the human ear cannot detect these sound waves. Ultrasound waves are produced by a transducer, which can both emit ultrasound waves, as well as detect the ultrasound echoes reflected. In most cases, the active elements in ultrasound transducers are made of special ceramic crystal materials called piezo- electric. This procedure is painless. Some discomfort may be felt in some instances, when the transducer is pressed against the skin for appropriate imaging. A standard scan takes approximately 30 – 60 minutes but please allow a little extra time as sometimes it can take a little longer than anticipated. Ultrasonography has a variety of uses in medical diagnostics. It is most well suited for imaging soft tissues that are solid and uniform or filled with fluid. In addition to other specialities, ultrasound is a very useful tool in detecting vascular problems with most of the smaller and larger blood vessels in the body. Using Doppler ultrasound technology, the flow of blood through the vessels can be observed and measured. It does not perform well when imaging calcified objects such as bone or objects filled with air like the bowel. Most ultrasonic exams are performed externally by running a transducer over the surface of the skin. Usually a gel is applied to the skin on which the transducer will glide during the exam. The gel helps prevent the formation of air pockets between the transducer and the skin that interfere with the ultrasonic signal. This ultrasound gel is water based, therefore when used as a coupling medium between transducer and body, helps in accurate assessment of depth and velocity measurements due to comparable sound velocities in soft tissue and water. Also help in quick drying from skin after cleaning the gel from skin.

Is ultrasound dangerous?

Ultrasound has been around for about 60 years now and studies have shown that it is a safe technique with no harmful side effects. Ultrasound imaging is not an X-ray as it uses sound waves and not ionizing radiation. Diagnostic ultrasound is a safe procedure that uses low-power sound waves. There are no known examples of tissue damage from conventional ultrasound imaging. Diagnostic ultrasound and/or sonography is considered a safe, non-invasive procedure by most every medical community. in part, because it uses low-power sound waves. No major medical source has proven any direct risks from a diagnostic ultrasound exam harmful enough to prevent its use. An ultrasound will not interact or cause any harm to a pacemaker.

Who will perform my scan?

Scans will be performed by an accredited medical sonographer who is fully qualified with suitable experience in performing the studies. A sonographer is a highly skilled medical imaging professional who uses ultrasound to perform specialised diagnostic examinations. The sonographer is legally required to scan the region requested on the referral from physician only. Ultrasound imaging is highly operator-dependent, and the outcome of a sonographic examination is dependent on the medical knowledge as well as the technical skills of the sonographer. During an ultrasound examination a sonographer will make real-time decisions to tailor the examination based on referral information, clinical context and the breadth of investigation required and selectively record anatomical images and physiological information that will form the basis of the clinical diagnosis A sonographer is trained in a post graduate level, specially to accurately perform an ultrasound examination and licensed for proper use of imaging equipment in a safe way. Sonographers understand ultrasound physics, cross sectional anatomy, physiology and pathology. Sonography requires specialized education and skills to view, analyse and modify the scan to optimize the information in the image. Because of the high levels of decisional latitude and diagnostic input, sonographers have a high degree of responsibility in the diagnostic process. They have core knowledge and skills in the applied anatomy, physiology and pathophysiology, application and operation of ultrasound imaging systems, ultrasound image recognition and comprehension, patient assessment, care and communication, critical thinking skills, ultrasound physics, occupational health and safety, infection control and quality assurance. Australian sonographers must be accredited by the Australian Sonographers Accreditation Registry (ASAR) and regularly monitored by continuing professional education.
Sonographer may ask to hold your breath – this is very important because when you breathe the organs go up and down in the tummy. When you hold your breath, the organs stay still allowing a better view of them.