Many patients go to the hospital, in addition to contact with doctors and nurses, blood tests, pharmacy medicine and other processes, there is also a common common content: do relevant imaging examinations. There are 4 types of equipment: B-ultrasound, X-ray, CT, and magnetic resonance.
In health institutions, they are equipped with B-ultrasound, as long as it is a comprehensive hospital, it must be B-ultrasound, X-ray, CT, magnetic resonance "four machines together", but there are still many people who can't tell the difference between their functions and differences.
What are the similarities and differences between the four imaging examination items of B-ultrasound, X-ray, CT, and magnetic resonance? What kind of disease tests are they suitable for? What is the difference in price levels?
B-ultrasound, X-ray, CT, and magnetic resonance have 4 things in common:
1. They are the real practical and universal medical contrast examination products in medicine, and the older means have long been eliminated, and the more advanced means than them, such as PET-CT, are only available in a few large hospitals, and the cost is very high.
2. Their value is to assist doctors to more accurately and quickly judge the type of disease, determine the treatment plan, and improve the efficiency of diagnosis and treatment.
3. They all represent the progress of medical science and technology in the past 100 years, and are the crystallization of multidisciplinary common focus. If the development of drugs has increased lifespan, and the popularization of vaccines has suppressed malignant diseases, then imaging equipment has greatly improved the accuracy of treatment.
4. They are the majority of modern science and technology awards, in addition to B ultrasound, X-ray, CT, and magnetic resonance have won a bunch of Nobel Prizes in physics, physiology and medicine.
What are the advantages and disadvantages of B-ultrasound, X-ray, CT, and magnetic resonance? Let's talk about each of them.
1. B-ultrasound
Principle: It is an abbreviation of ultrasound, which uses ultrasound to penetrate the body, receive the reflected signal, and use echo to "describe" the situation of the tested organs. With the advancement of technology, it has been upgraded to color ultrasound, which can detect the state of blood flow, and has three-dimensional, four-dimensional and other imaging modes.
Advantages: There is no radiation, it will not cause harm to the human body, it has high precision for all kinds of soft tissues, and it is important for early lesions and accurate diagnosis.
Examination time: relatively short, generally within a few minutes to 10 minutes per person, because B ultrasound is equipped in township hospitals, so it is the most used and the most common.
Main examination items: superficial small organs, superficial abdominal organs, gynecological examination items, cardiac and vascular examination.
Disadvantages: The clarity and resolution are slightly poor, there is a certain possibility of missing the diagnosis, it is easy to be disturbed by the influence of gas, and the examination results are greatly affected by the doctor's professional quality and subjective judgment.
2. X-ray
Principle: The use of X-rays through the human body, in different organs have different transmittance, contrast and generate images of different shades, is a kind of "two-dimensional projection", according to different rays and equipment, including traditional X-ray, digital X-ray.
Advantages: The image has high spatial resolution, clear edges, and is very intuitive and easy to use for bone status, cracks, joint disjoints, bleeding and other problems, and is a good hand for "flaw detection", and the cost is relatively low.
Inspection time: relatively short, usually two or three minutes can be completed, the exposure time varies according to the requirements of different parts.
The main examination items: lung diseases, bone problems, spinal lesions, intestinal obstruction, gastric perforation, stones, cardiovascular angiography, etc., are more convenient and fast, and are widely used in physical examination items.
Disadvantages: Because X-rays mainly show overlapping images, or with concomitant images, distortions and distortions, the details are slightly poorer, because there is a trace of radiation, it is not suitable for pregnant women and children, and is not suitable for neurological examinations.
3. CT
Principle: It is equivalent to an upgraded version of X-ray, which also uses X-rays to image through the human body, but it is a "three-dimensional projection", which can be used to detect the organs or tissues in layers. If X-ray is a "green train", CT is an "EMU".
Advantages: It is the most familiar imaging examination equipment for clinicians in large hospitals, very vivid and intuitive, the bright white part of the image represents high density, the dark part represents low density, the tomographic image is clear, and a variety of post-processing can be done, which is the "multiplier" of radiology.
Inspection time: The length varies, less than two minutes, and the longest takes more than ten minutes, with different requirements for scanning range and resolution.
Main examination items: It is suitable from head to toe, and has unique advantages in the brain, lungs, facial features, abdominal stones, microfractures, coronary arteries, etc., if you have a clearer examination for different organs, you need to use enhanced signal CT.
Disadvantages: There is some radiation, higher than X-rays, but still within the safe range. In some items of the nervous system, there are some dark areas, which are not good enough in soft tissue contrast, and the cancer lesions of hollow organs are not clearly displayed, and the cost is high.
4. Magnetic resonance
Principle: It examines the distribution of "hydrogen nuclei", due to the difference in hydrogen content in different organ tissues, so it can help doctors "see" the situation of human organs.
Advantages: It is the most accurate among the mainstream examination methods, the display of soft tissues and fine structures is very clear, the contrast is high, multi-directional imaging and multi-parameter imaging can be carried out, and the situation of different tissues can be reflected in more detail, and the lesions can be easily found, and there is no radiation.
Examination time: relatively long, usually starting from 10 minutes, more than tens of minutes, more than CT time, the specific time varies according to different parts.
Main examination items: It can overcome the blind spot of CT, X-ray and B-ultrasound, and show more accurate neurological and intracranial lesions, and is the first choice for spinal cord lesions, abdominal and pelvic lesions, early cerebral infarction, joint system, breast and other examinations.
Disadvantages: the sound of the equipment is relatively loud, it is easy to cause the patient's nervousness when running, and the examination position is relatively narrow, not suitable for patients with high fever and claustrophobia, if the patient has a pacemaker, magnetic resonance is not applicable, and all metal objects on the body need to be removed; Examination of lung tissue imaging is not good, usually not used, because the examination time is not short, it is not suitable for emergency treatment.
In the four examination methods of B-ultrasound, X-ray, CT and magnetic resonance, the doctor does not prescribe the examination items at will, but selects the most appropriate examination method based on the condition and progress. B-ultrasound belongs to the ultrasound department, and the price is mostly tens to one or two hundred yuan each time; X-ray, CT, and magnetic resonance belong to the radiology department, and X-ray is about 100 yuan each time, CT is about 200-600 yuan, and magnetic resonance is about 500-900 yuan.
CT and magnetic resonance equipment are similar in appearance, and some patients are difficult to distinguish, but there are actually two that are easy to see: CT doorway indicates radiation, and magnetic resonance doorway indicates magnetic field; The CT device will not be attached to the ceiling, but the MRI will touch the ceiling.
In short, the four mainstream imaging examination methods have their own advantages and disadvantages, but they are all doctors' right-hand men, which can identify the lesion as early as possible and treat it in time.