Difference between enhanced CT and MRI

Magnetic resonance imaging and CT are now very common methods of treating diseases. Magnetic resonance imaging is also known as MRI. There are many differences between these two treatment methods. CT irradiates the diseased area with X-rays to cause the diseased cells to regenerate or deform, while MRI is determined by the magnetic field. The imager can observe the growth environment of cells and perform direct treatment. Both are very convenient and simple, and cause little harm to the human body. Let's follow the editor to understand the difference.

MRI is the abbreviation of Magnetic Resnane Iamge, which means magnetic resonance imaging in Chinese. MRI places the human body in a strong magnetic field and uses radio frequency pulses to stimulate hydrogen protons in the body to cause nuclear magnetic resonance. It then receives the nuclear magnetic resonance signals emitted by the protons, positions them in three directions through the gradient field, and then uses computer calculations to form images in all directions.

Since the X-ray tube and detector of CT rotate around a certain part of the human body, it can only perform scanning imaging of the cross-section of the human body, while MRI can perform imaging of the cross-section, sagittal, coronal and any section. MRI can form various images through different scanning sequences, such as T1-weighted images, T2-weighted images, proton density images, water imaging, water suppression imaging, fat suppression, diffusion imaging, spectral imaging, functional imaging, etc. CT can only distinguish tissues with density differences and has low resolution for soft tissues, while MRI has better resolution for soft tissues, such as different signals of muscles, fat, cartilage, fascia, etc.

Therefore, CT and MRI are completely different examination methods. Although MRI has many advantages, it is a very different imaging method from CT and produces very different images. MRI can provide multi-directional imaging, is harmless to the human body, has good resolution for soft tissues, and has a variety of imaging methods. Not only do the images reflect the anatomical structure of the human body, but they can also provide physiological, pathological, and biochemical information. It is considered to have many advantages such as imaging at the molecular level. However, it is unable to image tissues that lack or contain very little hydrogen protons, such as dense bones, calcifications, and air-filled lungs. Since MRI imaging takes a long time, clear images cannot be obtained for comatose or agitated patients. Of course, patients with metal foreign bodies in the body cannot enter the magnetic field, which is a contraindication.

Therefore, MRI examinations also have insurmountable shortcomings. It cannot replace CT, and of course CT cannot replace MRI. The two should complement each other. This is why sometimes CT is done after MRI, or MRI is done after CT.