Method
Ultrasounds (sonography) are used to examine internal organs, vessels or soft tissues with sound waves and without X-rays.
When are ultrasounds used?
Ultrasound examinations are used to assess the following diseases and organs:
- Neck: thyroid, salivary glands, lymph nodes, soft tissues and vessels.
- Extremities: including muscles and soft tissues, tendons and joints.
- Chest area: mammary gland, fluid retention in the lungs
- Abdominal / pelvic organs: including liver, gallbladder, pancreas, spleen, kidneys, urinary bladder, arteries and veins.
Advantages of Ultrasounds (sonography)
- Ultrasound examinations aren’t invasive. Therefore it is a suitable examination for pregnant women and children.
- There is no radiation exposure.
- They produce real-time images. Therefore the assessment of movement sequences for cardiac actions can be seen.
- Dynamic representation of fluid flows is possible in Doppler sonography.
- Ultrasounds can be done quickly.
- Free cutting in any plane.
Disadvantages of Ultrasounds (sonography)
- There is limited accessibility when overlaying.
- The spatial resolution is lower than what is produced with CT or MRI examinations.
- Weight is a factor as the sound waves are absorbed more, ultimately reducing the penetration depth and thus the ability to assess the particular body part.
Patient information
- When examining abdominal organs, you should not eat, drink or smoke before your examination. Please ask your doctor or examination team about how many hours you should avoid food and drinks before your exam..
- To examine the kidneys and the urinary bladder, it may be necessary to drink a certain amount of fluid beforehand in order to achieve a good filling of the urinary bladder. Please ask your doctor or examination team about this.
- No preparations are necessary for the diagnosis of all other organ regions.
Ultrasound refers to sound waves in a range inaudible to humans (more than 20,000 oscillations per second, > 20 kHz). Frequencies in the range from 3.5 to 12 MHz are common in sonography.
In simple terms, sonography is the technique and ultrasound is the tool.
Sonography is based on the echo principle: the ultrasound that is radiated into the body. High-frequency sound waves (ultrasound) produce dynamic visual images of organs, tissues or blood flow inside the body.
The echoes are picked up by a transducer, passed on, amplified in the device and made visible on a screen as a curve or as a cross-sectional image.
Everything that is shown in black (dark) is hypoechoic (echo-free) penetrated clearly by the sound waves and is considered to be liquid, e.g. the gallbladder.
Everything that is displayed in white (light) (echo-rich) is not penetrated well by the sound waves. E.g a stone in the gallbladder.