What Are the Different Types of Medical Diagnostic Imaging?

Medical imaging refers to the technology and process of obtaining an internal tissue image of a human body or a part of the human body in a non-invasive manner for medical or medical research. It includes the following two relatively independent research directions: medical imaging system and medical image processing. The former refers to the process of image formation, including the study of imaging mechanism, imaging equipment, and analysis of imaging systems; the latter refers to further processing of the acquired images, the purpose of which is to make the original images not clear enough The restoration is either to highlight some feature information in the image, or to classify the image and so on. ^[1]

Medical imaging refers to the technology and process of obtaining an internal tissue image of a human body or a part of the human body in a non-invasive manner for medical or medical research. It includes the following two relatively independent research directions: medical imaging system and medical image processing. The former refers to the process of image formation, including the study of imaging mechanism, imaging equipment, and analysis of imaging systems; the latter refers to further processing of the acquired images, the purpose of which is to make the original images not clear enough The restoration is either to highlight some feature information in the image, or to classify the image and so on. ^[1]

Chinese name

Medical Imaging

Foreign name

medical image

Basic Introduction to Medical Imaging

As a science, medical imaging belongs to biological imaging, and includes imaging diagnostics, radiology, endoscope, medical thermal imaging technology, medical photography and microscope. In addition, including technologies such as electroencephalogram and magnetoencephalography, although the focus is on measurement and recording, no image is displayed, but because the generated data has localization characteristics (that is, contains position information), it can be regarded as another type Form of medical image.

In terms of clinical application, also known as medical imaging, or imaging medicine, some hospitals will have imaging medical centers, imaging medical departments or imaging medical departments, and will be equipped with related equipment. Specialized nurses, radiographers and physicians will be in charge. The operation of equipment, interpretation and diagnosis of images (in Taiwan, doctors are responsible), which is different from the radiology department responsible for radiotherapy.

In the fields of medicine, medical engineering, medical physics, and biomedical informatics, medical imaging generally refers to the science of researching image composition, acquisition and storage technology, and research and development of instruments and equipment. The research on how to interpret, interpret and diagnose medical images belongs to the auxiliary sciences of radiology, or other medical fields (such as neurological disciplines, cardiovascular disease disciplines ...).

Colleges offering this type of specialty

The medical imaging major is divided into four-year and five-year courses . For specific introduction, please refer to the entry " Medical Imaging Technology " on Baidu Encyclopedia .

History of Medical Imaging

Since the discovery of X-rays (generally called X-rays) by German physicist William Conrad Roentgen in 1895, a new page in medical imaging has been opened. Before that, when physicians wanted to understand the internal conditions of patients, In addition to direct dissection, palpation can only be used, but both methods have certain risks.

In 1978, at the annual meeting of radiology, an engineer named GN Hounsfield announced the results of computed tomography. This is the most important breakthrough in the field of radiology after X-ray discovery, and it is also one of the major achievements of science and technology in the 20th century. Hounsfield and Cormack won the 1979 Nobel Prize in Physiology and Medicine for their epoch-making contributions in radiation medicine.

The development of ultrasonic imaging equipment benefited from the development of radar and sonar technology in the Second World War. In the 1950s, simple A-type ultrasound diagnostic instruments began to be used in the clinic. In the 1970s, the B-type instrument capable of providing cross-section dynamics was introduced. Ultrasonic color flow mapping (CFM), which came out in the early 1980s, is a high-end ultrasound diagnostic instrument currently used in clinical practice.

American scholars first discovered the phenomenon of magnetic resonance in 1945, and the science of nuclear magnetic resonance spectroscopy was born. In the late 1970s, magnetic resonance imaging of the human body was successful. In 2003, the Nobel Prize in Victory or Medicine was awarded to Paul C. Lauterbur, an American scientist and Peter Mansfied, an American scientist who made outstanding contributions to magnetic resonance imaging research.

Medical imaging imaging technology

To date, medical imaging has developed other imaging technologies besides X-rays, and has developed a variety of imaging technology applications. In addition, in the application of biomedical information, in order to generate digital image files and image digitized files, they can be exchanged and consulted to develop medical digital image transmission protocol technology. Commonly used medical imaging technologies include:

Angiography: Also called arteriography , angiography , is the use of x-rays to irradiate the inside of the human body to observe the distribution of blood vessels, including arteries, veins or atria.

Cardiac angiography: Cardiac angiography is injected into the heart cavity or blood vessels through a cardiac catheter, so that the heart and blood vessel cavity are developed under X-ray irradiation. At the same time, there are methods such as rapid filming, television photography or video tape recording. The imaging process of the vascular cavity is photographed. From the results of the development, you can see the blood flow sequence containing the contrast agent and the filling of the blood vessels in the heart, so as to understand the physiological and anatomical changes of the heart and blood vessels. Is a valuable method for the diagnosis of cardiovascular disease. ^[2]

Computerized tomography (CT), or electronic computerized tomography, can be divided into X-ray CT (X-CT), ultrasound CT (UCT), and gamma-ray CT (-CT) according to the radiation used. Wait.

Mammography: It uses low-dose (approximately 0.7 millisieverts) X-rays to examine the breasts of humans (mainly women). It can detect various breast tumors, cysts and other lesions, which can help early detection. Breast cancer.

Positron emission tomography (PET): is a nuclear medical imaging technology that provides three-dimensional and functionally operating images of the entire body. It is the only technology that uses anatomical morphology to perform function, metabolism and receptor imaging. It is non-invasive and is currently one of the best clinical methods to diagnose and guide the treatment of tumors.

Nuclear magnetic resonance imaging (NMRI, Nuclear magnetic resonance imaging): Detect the electromagnetic waves emitted by an external gradient magnetic field, and thereby draw the internal structure of the human body.

Medical ultrasonography: Uses the physical characteristics of ultrasound, and uses electronic engineering technology to rapidly analyze, process, and visualize ultrasound transmission, reception, conversion, and electronic computers, so as to analyze the physical characteristics, morphology, and functions of human soft tissues A non-traumatic examination of the state of the condition, visualizing muscles and internal organs, including their size, structure, and pathological lesions.

Medical imaging composite application

PET / CT, Positron emission tomography with computerized tomography

Single photon emission computed tomography (SPECT / CT, Single photon emission computed tomography with computerized tomography)

Medical imaging development trends

1. From plane to stereo, multi-dimensional image

2. The morphological image reflecting anatomical structure is transformed into "functional imaging" reflecting organ function. The development of functional magnetic resonance imaging (functional MRI) is an obvious example.

3. Fusion of multi-modal images. The images from different time and different sources are registered in a coordinate system, which is convenient for clinical diagnosis and treatment plan formulation.

4. "Picture archiving and communications system" (PACS) was born to meet the needs of the acquisition, storage, output and transmission of massive medical images.

5. The rise of molecular imaging. Molecular imaging is the non-destructive observation of biological engineering in vivo at the molecular level. ^[1]