What is the difference between taking an x-ray, CT and magnetic **** vibration (MRI) test? How to choose?

How to choose? Retired doctor sang with the progress of medical science, all kinds of instruments for the clinic to provide advanced diagnosis and treatment methods, how to choose a safe, accurate, convenient, inexpensive examination method is not only a "big doctor love" "pots to help the world" the responsibility of the doctor, is all the patients pray, the doctor to improve the transparency of the examination program, so that patients can be more transparent, so that the patient's MRI (

MRI) examination. It is also the responsibility of a doctor who is "a kind doctor" and "a doctor who can help the world", and it is also the prayer of all the patients. It is very important for doctors to improve the transparency of the examination items so that the patients can have the right to know. X-ray film, CT, magnetic **** vibration in the clinic is a medical imaging examination of several commonly used methods, the imaging principle is different, often encountered some patients to consult the advantages and disadvantages of these three, some thought the more expensive the better, asked to do a CT to replace the ordinary X-ray film examination or asked to use the magnetic *** vibration instead of the CT examination, that the magnetic *** vibration is clearer than the CT, the CT is clearer than the X-ray examination, which is clear from the point of view of the medical science. There is a certain degree of one-sidedness, these three means of examination have their own strengths, on a variety of diseases examined by each focus, not to mention the price of nuclear magnetic *** vibration is not expensive! The following talk about the purpose of these tests and indications. 1, X-ray examination is the traditional means of imaging, it is the application of the earlier, the most common, the price is relatively cheap. Mainly used for the initial examination of some diseases, easy to find the more obvious lesions of tissues and structures, is the first choice for the initial screening of diseases. It has good diagnostic value for diseases with displaced fractures, bone diseases with bone changes, bony lesions in the joint area, impermeable foreign body deposits, cardiopulmonary organic diseases, and digestive system obstruction. In addition, X-rays can also take power position pictures, which can detect diseases in which the patient feels uncomfortable only when he changes his position, especially power position film examination. x-ray examination is inexpensive, with a small amount of ray casting, which is suitable for the majority of patients' routine examination. The machine is a high-voltage electric excitation of X-rays, but the amount of rays is very small, in addition to pregnant women have little effect on the body, do not have to worry about. 2, CT examination is currently developing rapidly, CT machine scanning part of the main by the X-ray tube and a different number of control detectors used to collect information. the X-ray beam of the selected level of scanning, and the intensity of its and the different density of the tissue due to the interaction with the corresponding absorption and attenuation. The detector converts the collected X-ray signals into electrical signals, which are converted into digital signals by an analog-to-digital converter (A/D converter), and inputted into a computer for storage and processing, so as to obtain the CT number of each unit of volume at that level, and arrange it into a digital matrix. Digital matrix by digital / analog (D / A) converter in the monitor to image, that is, the layer of cross-sectional image, it is high resolution, structural details show clearly, etc., but its disadvantage is that the spatial resolution is not high, not as good as the X-ray film, and the price is also more expensive. However, it is obviously better than X-ray film in displaying cross section, especially for high density tissues with clear image and high accuracy in measuring the distance between bony structures.CTA can clearly display the direction of blood vessels and vascular lesions, and the sensitivity of tumor examination is obviously higher than that of ordinary X-ray film. Moreover, multi-row spiral CT is capable of three-dimensional imaging, which helps to show tissue and organ lesions in three dimensions. However, CT scanning is limited to the technician's different levels of expertise and scanning level interval limitations, and cannot read the information of the examination area as a whole, resulting in a certain rate of missed diagnosis. In addition, CT shooting power phase is rarely used in clinical work, and CT on soft tissue imaging clarity and resolution is not high. 3, magnetic *** vibration (MRI) examination of modern development is also very rapid, nuclear magnetic *** vibration phenomenon originates from the atomic nucleus of the spin angular momentum under the action of an applied magnetic field. According to the principle of physics, when the frequency of the applied radio frequency field is the same as the frequency of the atomic nucleus spin motion, the energy of the radio frequency field can be effectively absorbed by the atomic nucleus, and provide assistance for the energy level jump. Thus a particular nucleus, in a given applied magnetic field, absorbs only the energy provided by the RF field at a particular frequency, thus forming a nuclear magnetic **** vibration signal. Its main advantage is that it can be imaged on any plane in three-dimensional space, and can be used to observe the lesions in the examined area from different angles, but it has the same spatial resolution as a CT film (the worst of the three), and is expensive, in addition, in the body with a magnetic or metallic substance patients can not do magnetic **** vibration. The biggest difference between magnetic *** vibration and X-rays and CT exams is that there is no X-ray radiation and very little damage to the body. It is mainly used to detect soft tissue diseases, and in orthopedics it is mainly used to detect intervertebral disc lesions, spinal cord lesions, meniscus lesions, inflammatory lesions and hemorrhagic lesions. Through different processing techniques, it can detect cancellous bone fracture such as vertebral fracture and pelvic fracture at an early stage; detect inflammatory diseases such as aseptic necrosis of femoral head, bone tuberculosis and bone tumor at an early stage, etc. MRA has high sensitivity to vascular diseases; the time for examination of each part is longer; patients with non-titanium metal in the body cannot undergo magnetic **** vibration examination; the imaging accuracy of bone tissue is not as good as that of CT; and the cost of dynamic MRI is dozens of times that of dynamic X-ray film. tens of times that of dynamic X-rays. To summarize, depending on the situation (patient's health, disease, economy, etc.), consider taking an X-ray, doing a CT or magnetic **** vibration. Generally for patients who do not quite understand the cause of the disease, it is best to do X-ray flat film to see if there is any abnormality; if no obvious abnormality is found or abnormalities are found and are not quite clear, in considering further examination, lumbar spine disorders, generally is a common orthopedic problems, such as spinal surgery, diagnosis of spinal fracture, spinal slippage, spinal deformity, spinal instability, and other diseases preferred X-ray film will be resolved! If it does not meet the needs of the clinical examination, it is best to take the advice of a specialist to use the appropriate means of examination for the condition. MRI is preferred in the diagnosis of intervertebral disc disease, especially cervical spondylosis, as well as spinal cord morphology, spinal cord deformity, spinal tumors, spinal tuberculosis, etc. For the diagnosis of spinal fracture, vertebral canal lesions, articular synovial joints, CT examination has irreplaceable advantages. In short, the three are not interchangeable, not the more expensive check the more problems can be found, it is best to understand some of the knowledge of the examination program, in order to be able to find problems as early as possible, accurate.