Why is there a shortage of medical imaging talents, but shrinking recruitment seems to be a trend?

When a patient goes to the hospital, the doctor will generally ask about the medical history and physical examination, measure the temperature, respiration, heart rate, blood pressure and test the blood. Some diseases can be diagnosed from the appearance of the body surface, but we can't directly "see" the diseases in the body outside the body. For the internal situation of the body, doctors should use various medical instruments to diagnose and determine whether there is any disease in the internal organs. In this respect, the medical imaging technology is most commonly used by doctors, that is, medical imaging instruments are used to "photograph" the internal situation of patients, and the diseases in the body are diagnosed according to the images obtained by "photographing". Most of these instruments are used for in vitro diagnosis and are harmless to human body.

Therefore, the function of medical imaging is to image the internal structure and function of human body with or without damage, and give three-dimensional, static or dynamic images of human body, so as to diagnose the internal health of human body. The internal structure and function of human body are very complex, so it is not easy to image the internal situation of human body without damage. This professional problem is called medical imaging. The expertise in this field is called medical imaging technology. The rapid development of this high technology is closely related to the protection of people's health.

The categories of modern imaging include: routine X-ray diagnosis, X-ray radiography, DSA digital subtraction angiography, CT(X-ray computed tomography); Ultrasonic imaging includes B-ultrasound; Magnetic resonance imaging; Nuclear medicine includes ECT.

X-ray imaging principle:

X-ray is a kind of high-energy light, which can penetrate many substances, including human tissues. When X-rays pass through the human body, they interact with substances in the body, so that some X-rays are scattered or absorbed, and the rest can pass through the human body, and the intensity of X-rays passing through the human body is weakened. It is precisely because of the different penetration intensity of X-rays through different parts of the human body that X-rays recorded in vitro have different exposures, and the "projection" images recorded by film will present images with different depths. In this way, X-ray fluoroscopy or "filming" the human body can also diagnose the lesions inside the human body. Doctors use the above characteristics of X-ray to understand the internal structure of human body.

DSA Digital Subtraction Angiography (DSA) is a new technology combining computer with traditional X-ray angiocardiography. X-ray CT refers to X-ray computed tomography. During X-ray CT scanning, the human body is irradiated and scanned at different angles with X-rays in vitro. A plurality of projection images are obtained and processed by a computer to form a three-dimensional image.

Ultrasonic imaging

Using the interaction between the physical characteristics of ultrasound and the acoustic characteristics of human tissues and organs, information is generated, and the information is collected and processed to form an image. Ultrasonic diagnosis is very popular because of its intuitive performance, high detection rate, simple operation and rapid diagnosis, especially for congenital malformation. Widely used in obstetrics and gynecology. Pregnant women usually do ultrasound examination at 20-22 weeks of pregnancy, which can show the whole and internal structure of the fetus, so they can diagnose fetal malformation. Color B-ultrasound can also diagnose cardiac and great vascular malformations.

Principles of medical magnetic resonance imaging

Different from X-ray photography and CT, it uses hydrogen protons (H+) in a large amount of water in human body to image. A single proton is positively charged and can rotate around its own axis at the same time. This is called spin. In order to make it easier to understand, the rotation of protons is often compared to the gyro that many people played when they were young. When it rotates at a high speed, it is in a vertical state. If you gently whip it with a whip, it will deviate from the axis and then gradually return to the upright rotation state. There are countless hydrogen protons in the human body. Because the direction is chaotic, the magnetic fields cancel each other out and do not show any magnetic fields to the outside world. Just like a group of naughty children making noise and running around in the playground. Now the teacher needs to line them up. So how can we turn hydrogen protons into queues? If you put the human body into a strong magnetic field, the situation will change dramatically. At this time, the protons that make up the human body, like small magnetic rods, will be temporarily arranged in the direction of the magnetic field to form large magnetic rods. After the protons are arranged in a queue, the signal is large enough to be detected by the instrument and processed by the computer to get the image of the human body.

Nuclear medical imaging:

It is based on the fact that after organs ingest radioactive substances (imaging agents), due to the distribution differences between target organs and non-target organs, normal tissues and diseased tissues, the distribution of imaging agents is significantly different when target organs selectively ingest, diseased tissue cells selectively ingest, or do not ingest because of no normal function. Firstly, radioactive drugs are injected intravenously, and then the information of nuclear rays emitted from the target organ is collected by instruments, and images are synthesized by computers according to the radiation densities emitted from various parts. This kind of image directly reflects the function of cells in various parts of organs, so it is called "functional imaging"

So for ordinary people, they are concerned about the cost of inspection, the rationality of inspection, the harm to human body and the consequences. There are many factors involved here: for example, the relationship between doctors and patients, the level of hospitals, the diagnostic skills of attending doctors, the income level of patients and so on. For professional radiologists, it involves' comparative imaging'. It is necessary for doctors and patients to understand the selection principles of comprehensive images. Sometimes patients don't understand and think that doctors are abusing examinations, so here is a communication problem. Doctors should explain the imaging lesions to patients or their families in order to gain their understanding, which also involves patients' right to know.