Ultrasound equipment can be used to detect certain diseases quickly, safely and painlessly. Ultrasound belongs to the so-called imaging techniques and it is impossible to imagine modern medicine without it.
What is an ultrasound scanner?
The ultrasound scanner can be used to detect certain diseases quickly, safely and painlessly. Ultrasound examination (sonography) is one of the most common imaging methods used in medicine for diagnosis. With the ultrasound device, the doctor can detect diseases and control the course of treatment (therapy). Ultrasound waves are used to produce multidimensional images of different regions of the human body. Ultrasound is particularly suitable for examining organs and tissues that are filled with a lot of fluid. These include the liver, gallbladder, spleen, pancreas, kidneys, heart, thyroid, joints, vessels, lymph nodes and breast. On the other hand, ultrasound is not suitable for the lungs and intestines, which contain a lot of air. The different tissues appear on a monitor in different shades of gray, depending on their density. Bones are completely white, liquids black. The doctor usually performs the examination with the ultrasound machine while lying down, sometimes while standing or sitting. The examination itself is based on an echo principle. Sound waves are absorbed or reflected in the patient’s body depending on the type of tissue. The reflected sound waves are sent back to the ultrasound machine and converted into an image by a computer.
Shapes, types, and species
Many women are familiar with the ultrasound machine from their pregnancy, because it provides a good visualization of the unborn child in the uterus. In other medical specialties, such as emergency medicine, surgery, urology, ophthalmology, and otolaryngology, the device is used to detect tumors or cysts, enlarged organs, or stones in the gallbladder and kidneys. Special methods are used for this purpose. In abdominal ultrasonography, the abdominal cavity (abdomen) is examined for changes, cancerous tumors or gall and kidney stones. To show the structure of the breast tissue, a mammary sonography is performed. In cardiology, physicians examine the heart with ultrasound waves, which is called echocardiography. Doctors use Doppler ultrasonography to check the flow of blood in the vessels, i.e., arteries and veins. This can detect narrowing or occlusion, which can become life-threatening for those affected. In endosonography, doctors examine the esophagus, pancreas, stomach or rectum. Ultrasound waves are not sent through the skin from the outside, but from the inside. With the aid of a probe or an endoscope, the transducer is inserted through the mouth (orally) or the anus (rectally). For this purpose, patients are sedated beforehand, i.e., put into a kind of half-sleep.
Structure and mode of operation
During the examination, an ultrasound device produces high-frequency sound that is inaudible to the human ear. The device consists of a transducer, a computer, and a monitor (screen). In order for the transducer to work properly, the doctor applies a gel to the skin and places the transducer on top of it. The gel prevents air from getting between the transducer and the skin, because sound cannot penetrate air. Crystals located in the transducer begin to vibrate when an alternating electrical voltage is applied. These oscillations, the ultrasound waves, penetrate the tissue and reach, for example, the abdominal cavity. There they hit organs and tissue and are reflected, i.e. reflected back to the transducer. It registers these sound waves and forwards the data to a computer unit. This unit converts the transmitted data into multidimensional images that can be viewed on a monitor. In this way, the physician gets a spatial idea of the size, shape and structure of the examined organs, tissues and vessels. He receives information about the direction of blood flow, its velocity and strength. By moving and angling the transducer on the skin, the body parts being examined can be viewed from different directions. If an endosonography is performed, i.e. an ultrasound examination from the inside, for example to clarify the cause of severe abdominal pain or disorders of the sphincter muscle in the anus, the patient must be sedated and fasting beforehand.He must not have eaten or drunk anything for several hours before the examination. Otherwise, the image quality would be severely impaired. Endosonography can also be used to diagnose cancer of the rectum.
Medical and health benefits
Ultrasound equipment has many advantages. The examination is completely safe and painless for patients. At most, they feel a slight pressure when the doctor moves the transducer over the area to be examined. Unlike X-rays, patients are not exposed to radiation. The examination does not cause any physical or mental stress. For this reason, the procedure is also used on children and pregnant women. Gynecologists use ultrasound to check the development of the unborn child. Through this screening examination, malformations and multiple pregnancies can be detected. This is not connected with any risks for mother and child. An ultrasound can be performed very quickly. In a few seconds, the doctor usually gets information about where the patient’s severe abdominal pain comes from or why his liver values are elevated. With the ultrasound device, he can detect gallstones, changes in the heart valves or enlargements of the thyroid gland. Further examinations are then no longer necessary. Ultrasound machines are also used in intensive care units and in the operating room. Modern devices are now mobile, so that the doctor can also move them to the patient’s bedside and perform the examination there. There are now even portable versions that run on batteries and can be taken to home visits or used in nursing homes and emergency ambulances. Ultrasound is very inexpensive compared with catheter examinations, computed tomography, and magnetic resonance imaging, and is not associated with any hazards.
