Imaging: what is MRI

summary

Magnetic resonance imaging (MRI) is a kind of imaging equipment for medical examination, which is made by using the phenomenon of MRI. Let's share with you the knowledge about MRI.

Imaging: what is MRI

The first is to place the human body in a special magnetic field and use radio frequency pulses to excite the hydrogen nuclei in the human body, causing the resonance of the hydrogen nuclei and absorbing energy. After stopping the RF pulse, the hydrogen nucleus emits a radio signal at a specific frequency and releases the absorbed energy, which is recorded by an external receiver and processed by an electronic computer to obtain an image, which is called nuclear magnetic resonance imaging.

Second: nuclear magnetic resonance (NMR) is a physical process in which the spin energy level of an atomic nucleus with nonzero magnetic moment splits under the action of an external magnetic field and resonantly absorbs a certain frequency of radio frequency radiation. Nuclear magnetic resonance spectroscopy is a branch of spectroscopy. Its resonance frequency is in the radio frequency band, and the corresponding transition is the nuclear spin transition in the nuclear Zeeman level.

Third: MRI application: MRI has become a common way of imaging examination. As a new imaging examination technology, MRI will not affect human health, but six groups of people are not suitable for MRI examination: even people with pacemakers, people with or suspected of metal foreign bodies in the eyeball, aneurysm clips Ligation, metal foreign body retention or metal prosthesis, life-threatening critical patients, claustrophobia patients, etc. Do not bring monitoring equipment and rescue equipment into the MRI examination room.

matters needing attention

Magnetic resonance imaging is a new medical imaging technology based on the principle of magnetic resonance. It has excellent diagnostic function for brain, thyroid, liver, gallbladder, spleen, kidney, pancreas, adrenal gland, uterus, ovary, prostate and other parenchymal organs, as well as heart and large blood vessels. Compared with other auxiliary examination methods, MRI has the advantages of more imaging parameters, faster scanning speed, higher tissue resolution and clearer image. It can help doctors "see" the early lesions that are not easy to detect. At present, it has become a sharp tool for early screening of tumor, heart disease and cerebrovascular disease.