MRI is a method of drawing the state of hydrogen nuclei in water and fat in the body using magnets and radio waves. MRI requires a tubular device that is equipped with a magnet that is tens of thousands of times stronger than the Earth's magnetism and creates a uniform magnetic field (A in the figure). Creating this uniform magnetic field requires a very high level of skill, which is why MRI equipment is expensive. In addition, in order to receive the radio wave signal generated from the body, a receiving coil corresponding to each body part is required. In the case of the heart, it is the receiving coil dedicated to the heart (B). I put my body in a magnet tube with a uniform magnetic field, irradiate the radio waves in a short time, and receive the radio waves coming out of my body when the radio waves are stopped to create an image ( C). A closer look reveals an image of the "spin" of hydrogen nuclei inside the body (D).

 

First, the hydrogen nuclei are well aligned in a certain direction in a strong magnetic field. Next, it irradiates a weak radio wave in the frequency band of the radio, and causes the hydrogen nucleus contained in a certain cross section of the body to absorb the energy of the radio wave. When the radio wave irradiation is stopped, the absorbed energy is released and returned to its original state, and the radio wave signal obtained at that time is imaged by a computer. In MRI, the vibration noise of the machine is generated every time the radio wave is applied, which may be quite noisy. This is the cause of the loud noise you hear on an MRI scan. ​

In addition, cardiac MRI can visualize the coronary arteries without radiation exposure and without the use of contrast media. At the same time, it is possible to evaluate the pump function (cardiac function) of the heart, and the evaluation of cardiac function by cardiac MRI is considered to be the most reliable and has been adopted in clinical studies on various cardiac functions. In addition, contrast-enhanced cardiac MRI examinations using contrast media have the high potential of being able to obtain all the information obtained separately from conventional cardiac imaging such as echocardiography, myocardial scintillation, and coronary angiography in about one hour. I'm waiting. Therefore, it is called a "one-stop shop" overseas.