X RAY: X-ray examination principle is to penetrate the human body, according to different organs and different density of the human body, X-ray will have different degrees of attenuation, the formation of black and white differences in the image. Therefore, the contour and density of organs can be determined by imaging.
CT: The imaging principle of CT examination is relatively abstract, probably introduce everyone to computed tomography (CT) is to use x wiring harness, the level of the thickness of the inspection area must be scanned to the human body, by the detector accept through the level of X-ray after converted to visible light by a photoelectric converter into electrical signals, then by the analog to digital converter, converted to digital signals, input computer processing, Image formation processing as the selected level, divided into a number of rectangle of the same size, called voxel, scanning the information obtained by the calculation for each individual element of the X-ray, attenuation coefficient and absorption coefficient, and then arranged in the matrix, namely digital matrix, digital matrix, can be stored on disk or CD via digital to analog converter, the digital matrix of each number, The CT image is transformed into black to white, small squares of different gray scales, namely pixels, arranged in a matrix.
B ultrasound: No radiation, but the principle of penetration of B ultrasound is weak with ultrasound. Penetrating the human body, when the sound wave meets the human tissue will produce reflected wave, by calculating reflected wave imaging.
MRI: You can cut layers at any Angle without radiation. The anatomy and lesions of the brain, spine and spinal cord are better than CT. MRI development is simply equivalent to shaking the water molecules to vibrate, then calming down and feeling the vibrations inside. Therefore, MRI is also referred to as a wobbly examination.
