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Medical quality concept build love human health
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| What used MRI imaging sequences and inspection methods |
| Date：2014-11-25 14:30:00 Views：1427 |
Magnetic resonance image is formed by scanning using specific imaging sequences obtained. Currently, the most commonly used clinical spin - echo sequence (SE sequences). By changing the sequence of TR (repetition time RF) and TE (echo time) two parameters can be obtained respectively β proton density, T1 and T2-weighted images, the weighted images in three different imaging parameters, each representing the organization the three different magnetic resonance characteristics, in order to distinguish between normal tissue and identify lesions. In addition, inversion recovery sequence (IR sequence), the sequence of the resulting image, can reflect characteristics of severe tissue T1 (T1-weighted severe); saturated reply sequence (SR sequence) sequence is added only proton density; partially saturated sequence (PS sequence) for T1-weighted sequences. These sequences are not as SE series is more popular, the application is not very extensive.
Fast imaging sequences effectively promote the clinical application of magnetic resonance imaging technique. For example, imported from West Germany RARE sequence, is a heavily T2-weighted imaging sequences, which showed lesions in terms of high sensitivity. FLASH, FISH and other sequence is fast imaging sequences, they scan imaging time in milliseconds (conventional sequence of scanning and imaging time, generally in minutes or seconds), therefore, largely overcome long time magnetic resonance imaging scan of fatal weakness, dynamic magnetic resonance imaging and magnetic resonance imaging cinematography, creating the necessary conditions.
When the patient MRI, to avoid items with iron and other paramagnetic substances, such as watches, metal necklace, dentures, metal buttons, metal IUDs, etc. into the examination room, because these substances with paramagnetic items can affect the uniformity of the magnetic field, generated in large image no signal artifacts, is not conducive lesions appear. Patients with pacemakers, MRI done strictly prohibited. Metal shrapnel in vivo retention, postoperative residual silver clip (which may contain a small amount of paramagnetic silver clip components), the patient is fixed within the metallic plates, fake joints, the MRI to be cautious, you must check should be closely observed, if the local patient discomfort, you should immediately discontinue checks to prevent shrapnel, silver clip and other mobile in the high magnetic field, resulting in damage to adjacent large vessels and important organization.
When the patient MRI, to avoid items with iron and other paramagnetic substances, such as watches, metal necklace, dentures, metal buttons, metal IUDs, etc. into the examination room, because these substances with paramagnetic items can affect the uniformity of the magnetic field, generated in large image no signal artifacts, is not conducive lesions appear. Patients with pacemakers, MRI done strictly prohibited. Metal shrapnel in vivo retention, postoperative residual silver clip (which may contain a small amount of paramagnetic silver clip components), the patient is fixed within the metallic plates, fake joints, the MRI to be cautious, you must check should be closely observed, if the local patient discomfort, you should immediately discontinue checks to prevent shrapnel, silver clip and other mobile in the high magnetic field, resulting in damage to adjacent large vessels and important organization.
MRI of the upper abdomen (liver, pancreas, kidney, adrenal gland and other checks) should be fasting before the test drink enough water, can make the boundaries of the stomach and the left lobe of the liver, spleen and other display more clearly. |
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