I. How does magnetic resonance imaging (MRI) form an image? Hydrogen atoms are the most abundant elements in the human body, and MRI is the use of hydrogen atoms in the human body, after being excited by pulses within a strong magnetic field, the magnetic resonance phenomenon, after spatial encoding technology, the electromagnetic waves (i.e., magnetic resonance signal) emitted during the magnetic resonance process and the parameters related to these electromagnetic waves, such as proton density, relaxation time, flow effect, etc., receive conversion, through the processing of electronic computers, and finally The image is formed in a clear and richly layered manner. What are the advantages of MRI examination? MRI is a new kind of imaging examination without radioactive damage. MRI is a new type of imaging examination without radioactive damage. 2, it can directly make body layer images in various directions, which can comprehensively display the structure of the examined organ or tissue and accurately locate the lesion. 3.It is not disturbed by bone image, and has high diagnostic value for lesions in the head and other places and metastatic tumors. 4. It shows the disease structure more clearly and can clearly distinguish soft tissues such as muscles, tendons and fat. What is the scope of application of MRI? 1.Cranial five senses: the application in the nervous system is more mature. It is better to examine stroke, cerebral white matter lesions, inflammation, tumor vascular lesions and congenital malformations. MRI is preferred for hyperacute cerebral infarction, pituitary and head and neck vascular lesions. 2, abdomen: MRI has advantages in liver, bile, pancreas, spleen, kidney, adrenal gland and retroperitoneal lesions. MRI is recommended for obstructive xanthogranuloma, prostate, testis, uterus and adnexal lesions. 3, spine and extremities: MRI has advantages in the examination of intravertebral lesions, intervertebral discs, articular cartilage, synovial membrane and muscle lesions. Especially, the examination of knee meniscus, ligament, rotator cuff injury and joint soft tissue makes up for the deficiency of X-ray and CT. MRI is preferred for large blood vessel lesions of the heart, especially for aneurysms and vascular malformations. What do I need to pay attention to in MRI examination? MRI is prohibited for pacemakers, neurostimulators, aneurysm ligation with silver clips. If you have a metal foreign body or a metal prosthesis in your body, please specify the location and type so that the MRI doctor can decide whether the examination can be performed. 3.Persons with life-threatening conditions and with monitoring and resuscitation equipment are not allowed to undergo MRI examination. 4.For restless and uncooperative children, the examination can be performed after the medication is put to sleep. 5, with metal birth control ring if the pelvic examination is required to remove before the examination can be performed. Metal things must be given to MRI staff for preservation, such as: gold jewelry, watches, coins, keys, hair clips, credit cards, pocket knives, etc. Metal-containing items that may adorn the skin, such as wigs, false eyelashes, etc.