MRI of the chest

MRI is also called nuclear magnetic resonance. MRI diagnosis is widely used in clinical practice, and it is becoming more and more perfect. Although the time is short, it has also shown its superiority. In the mediastinum on the MRI image, the tumor can be observed and its anatomical relationship with the surrounding blood vessels, which clearly shows the invasion of the armpits, brachial plexus and spinal canal. It is helpful for the diagnosis of hilar lymphadenopathy and central lung cancer. Cardiac macrovascular MRI has the advantages of rapid, time-saving and low patient pain. It can show the size of the atrioventricular, blood vessels, lumens, and can observe hemodynamic changes, which is conducive to functional diagnosis and abnormal tissue. Basic Information Specialist Category: Respiratory Examination Category: Nuclear Magnetic Resonance Applicable gender: whether men and women apply fasting: not fasting Reminder: For children and children who are not cooperating, and those who are restless, in order to keep the patient's position and heart rate stable during the examination, a sedative must be given to ensure the quality of the MRI image. Normal value Normal image performance: 1. Strange and lungs contain black, no signal zone due to air. 2. The large blood vessels of the heart have a black signal-free area due to the "flow effect". 3. Cortical bone and calcification are black and no signal area. 4. Since it has a longer T1 and a shorter T2 relaxation time with other soft tissues, it has a lower gray signal area. 5. Adipose tissue has a very short T1 and a short T2, a white high signal region on the T1-weighted image, and a grayish white color on the T2-weighted image. 6. The aqueous liquid has a long T1 and a long T2, a grayish black area on the T1-weighted image, and a white area on the T2-weighted image. Clinical significance MRI can make a qualitative diagnosis of the problems found on X-ray films. (1) Mass 1 can identify the nature of the mass such as cystic, substantial, fatty or vascular (arteriovenous malformation); 2 clear the location, size and extent of the mass, and can confirm the anatomical relationship between the mass and the mediastinum. (2) mediastinal widening 1 can determine the mediastinal widening is pathological or anatomical variation; 2 can identify mediastinal widening is substantial, cystic and vascular abnormalities, aneurysms or adipose tissue mass; 3 can observe esophageal cancer The extent of invasion to the outside of the tube; 4 can be diagnosed for the diagnosis of fibrosis or granulomatous mediastinal inflammation; 5 to determine the extent of tumor invasion of the mediastinum. (3) The enlargement of the hilar is due to pulmonary vascular disease or substantial mass (including enlarged lymph nodes). MRI is superior to CT with good contrast resolution, so a tumor with a diameter of 1 cm can be detected. MRI is easier to identify lumps and blood vessels than CT. (4) Defining the extent of tumor invasion to the pleura and chest wall is important for staging the tumor and formulating a treatment plan. (5) MRI can show the diagnosis of myocardial infarction, cardiomyopathy, valvular disease, pericardial lesions, congenital heart disease and cardiac tumors. (6) MRI is the first choice for the examination of cardiac macrovascular disease. This is because 1 has a good contrast between the blood and the heart structure in the heart due to low blood flow signal or no signal. 2 Because of the high contrast resolution of MRI, it can Clearly distinguish the myocardium, endocardium, pericardium and pericardial fat; 3 if ECG is gated, the myocardial activity of the cardiac cycle can be dynamically observed; 4 no trauma, no contrast agent, can show the atrium, ventricle and large vessel lumen The examination is very safe; 5 any tomographic image can be obtained without changing the patient's position; 6 rapid imaging sequence can observe the movement state of the heart and large blood vessels, and quantitatively analyze the cardiac function; if supplemented by echocardiography, It can confirm the diagnosis of most complex cardiovascular diseases. Precautions (1) MRI diagnosis of chest disease should be combined with clinical data and other imaging studies to improve the diagnosis rate. (2) Patients with a pacemaker or a metal foreign body in the thoracic cavity, aneurysm surgery or other metal clips on the postoperative large blood vessels are contraindicated for MRI. (3) Cardiac examination, layer thickness is 6~10mm, no gap is left as far as possible; the average number of signals is 2~4 times. For patients who can cooperate closely, the average number of signals is 4 times to obtain high quality images. When the critical or pediatric is not well matched, the average number of signals can be changed to 2 times to shorten the inspection time. (4) For children and children who are not cooperating, as well as patients with irritability, in order to enable the patient to remain in position during the examination and to stabilize the heart rate, a sedative must be given to ensure the quality of the MRI image. Inspection process MRI examination. Not suitable for the crowd It is not advisable for pregnant and lactating women to perform this test. Adverse reactions and risks Generally no adverse reactions.