Sonography. What is it and what is the method of research based on?
When a doctor directs a patient to an ultrasound, unnecessary questions usually do not arise. But if the destination uses the mysterious word "sonography", the questions are poured like peas. So, it is worth investigating, sonography - what is it? And in what cases is the patient given such an appointment.
Associations
The first patient associations are related to sleep, but sonography has nothing to do with this. Ultrasound and sonography are different names for one procedure. For this same study, the name echography is sometimes used. Proceeding from this, it is possible to draw a simple conclusion: ultrasound, sonography, sonography - what is it? This is an ultrasound study that evaluates the morphological and functional parameters of human organs and tissues.
The method based on
The ultrasound method is based on the features of ultrasonic waves transmitted through the body. In any living being, organs consist of tissues of varying density and resistance. Due to this, ultrasound is reflected, refracted, scattered or absorbed. As a result, an image appears on the receiving device. That is, ultrasound is actually the recording of echoes reflected from the objects.
Medical equipment for ultrasound( sonography) uses frequencies from 1.5 to 29 MHz. The maximum height of sound that the human ear can perceive is 20 kHz. The resulting image is not just a contour of the internal organ or bone site, as in x-ray, but a reflection of internal structures.
Brief description of the device
Ultrasound is used for the survey. Sonography - what is it? Are all the machines the same? What elements do they consist of? The best thing in the device of ultrasound apparatus can understand physics. They understand what a piezoelectric effect is, they understand the lengths, vibrations and frequencies. It is enough for an ordinary patient to know that the apparatus consists of the following elements:
- of an ultrasonic wave generator, that is, a pulse sensor that emits and simultaneously receives reflected signals;
- ultrasonic sensor-transducer, in which there are a large number of piezoelectric crystal converters, the sensor has a focusing lens, which allows to concentrate attention on the required depth.
Types of transducers( sensors)
The initial unit is made for mechanical and electronic devices. Scanning by a mechanical sensor is performed by the motion of the radiating element( rotation or rocking).The main drawback - low resolution pictures, vibration and noisy work. Modern ultrasound sonography abandoned the outdated model, preferring to use electronic versions.
Electronic sensors relate to more modern equipment. The image is scanned electronically. The picture is more clear and complete. Noise and vibration in the operation of equipment are absent.
Ultrasonic scanning is divided into linear, convective and sector type. Based on this, 3 types of sensors are used:
- Linear. Uses a frequency of 5-15 MHz. It produces an image of the investigated area with a high resolution image, the size of the organ corresponds to the width of the sensor, but the depth of scanning is not more than 11 cm. It is difficult to ensure a uniform fit of the wide sensor in order to obtain a high-quality picture. Used to scan the thyroid gland, breast, small joints and muscle tissue.
- Convex. The frequency is 1.9-7.5 MHz. The scanning surface is shorter than the linear sensor. Allows a tight, even fit to the skin. Gives out a narrow picture, somewhat distorted in size, but the depth of inspection is up to 25 cm. It is used for examination of the organs of the abdominal and retroperitoneal cavity, urogenital system, large joints( hip, for example).
- Sectoral. Uses a frequency of 1.5-5 MHz. The image is larger than the real one. Allows scanning at great depths. It is most often used for echocardiography.
Different types of sensors are used to examine the organs of the abdominal cavity, heart, thyroid, breast, spine and joints. In addition, there are microsensors for endoscopy and needle biopsy.
Examination of pregnant women
Optimal option for a complete examination of pregnant women is computer sonography. Such equipment allows you to carefully consider the condition of the fetal organs, starting with a four-centimeter size. The examination is completely safe. It helps with the fourth week of pregnancy to listen to the heartbeat, to identify and eliminate the threat of miscarriage, to clarify the period of pregnancy, to determine the developmental delays and other abnormalities.
Passage of the fallopian tubes
The need to assess the patency of the fallopian tubes occurs in women who can not become pregnant for a long time. Sonography of the fallopian tubes is one of the methods for evaluating the reasons why an egg can not meet a sperm.
First the doctor examines the condition of the uterine cavity, makes sure that the woman is not pregnant and has no adhesions, polyps and knots. Further into the cervical canal, physiological saline is injected, and sonography is assessed for the patency of the fallopian tubes. If the pipes are passable, the liquid merges on both sides of the organ into the abdominal cavity. If the liquid does not drain, but fills the segment of the uterine tube and uterus, then the tube is impassable. Ultrasound can accurately determine the location of the block.
If the patient understands the meaning of the term "sonography", what it is and why the doctor prescribed the examination, then he does not feel afraid, is ready to fulfill the necessary requirements of the doctor and correctly refers to the procedure. Much depends on this. Because often, instead of examining and treating frightened patients turn to charlatans and "healers", losing valuable time.