Terminology of medical imaging

1. MRA: Magnetic Resonance vascular imaging is an MRI Technique for vascular imaging. Generally, the vascular development is safe and non-invasive, and can be observed from multiple angles without injecting contrast agents, however, at present, MRA shows that small vessels and small lesions are still not satisfactory, and they cannot completely replace DSA.

 

2. EPI: Echo plane imaging, which is currently the fastest imaging technology, can collect a complete image within 30 ms. The EPI technique can be combined with sequences of all conventional imaging.

 

3. mrs: magnetic resonance spectroscopy is a method for determining molecular composition and spatial distribution by using the chemical displacement of Mr, it is a new non-invasive technique for studying tissue metabolism, biological changes and Quantitative Analysis of compounds in living organs.

 

4. mr water imaging: long TR and long TE are used to obtain heavy T2 weighting, so that the static or slowly flowing liquid in the body can present a high signal, while substantial organs and fast-flowing liquids such as arterial blood present low-signal techniques. Through MIP reconstruction, images similar to direct contrast of Water organs can be obtained.

 

5. window width: it refers to the CT value range included in 16 gray-scale images. The organizations within this CT value range are displayed in Different Simulated gray-scale images, the organizations with CT values higher than this range are displayed in white, while those with CT values lower than this range are displayed in black.

 

6. Window Level: Also known as window center. Generally, the CT value center of the observed tissue should be selected. The brightness of the high and low image of the window position. Increase the brightness of the window image, and decrease the brightness.

 

7. artifact: In the process of scanning and processing information, the human body does not exist for some reason or for some reasons, but different types of images are displayed in the image. It mainly includes Motion Artifacts, high-density artifacts, and machine failure artifacts.

 

8. voxel: The CT image assumes that the layer of a certain part of the human body has a certain thickness and is divided into several small cubes arranged by matrix, that is, the basic unit, the density of matter in each unit is represented by a CT value. These small units are called theme.

 

9. tomography: High-Resolution CT scan, using thin-layer scanning, high-Spatial Resolution Algorithm reconstruction and special filtering processing, CT images with good spatial resolution can be obtained, compared with conventional CT scans, the displayed small lesions and fine structures were superior.

 

10. CTVE: CT simulated endoscopic imaging, combining volumetric data with virtual reality in the computer field, simulates the endoscopic examination process ..

 

11. Spatial resolution: the minimum size limit of the Space ry of the identifiable organizations in the image under the condition of a certain density difference, that is, the resolution capability of the subtle structures in the image.

 

12. contrast enhanced scan (contrast enhancement): water-soluble organic iodine injection is injected into the vein and then scanned at the lesions. Due to the difference in iodine concentration in the lesions of the organ, the density difference is formed, so that the lesions are displayed more clearly, and the nature of the lesions can be determined according to the contrast enhancement characteristics.

 

13. EBCT: ufct, also known as ufct, is an x-ray scan generated by the electron gun emitting electron beam to target four rings. The scanning time of one layer can be as short as 50 ms, which is feasible for CT observation in movies.

 

14. Multi-layered spiral CT with multi-row detector matrix. each row of detector matrix can be used to reconstruct an image, or multiple rows of detector data can be used to reconstruct an image.

 

 

15. Artificial comparison: Artificial comparison is a comparison that artificially introduces a substance to human organs or gaps to produce density differences.

 

 

 

16. Natural comparison: Natural density difference in different organs and tissues of the human body, called natural comparison

 

17. CT: Computed Tomography performs layer-by-layer scanning on a selected part of the human body using the X-ray bundle. After the X-ray dose is determined, the absorption coefficient of each unit volume in the scanning layer is obtained by digital processing, this is an imaging technique used to reconstruct an image.

 

 

18. MRI: magnetic resonance imaging uses signals produced by magnetic resonance phenomena to reconstruct image imaging techniques.

 

19. PACS: Picture Archiving and communicating system, which is an image storage and transmission system.

 

 

20. interventional radiology: based on image diagnosis, and guided by imaging equipment, specific diagnostic devices are imported into the relevant parts of the lesion, non-surgical treatment or diagnosis materials such as source and pathology are obtained, which has the advantages of small trauma, high curative effect, and combination of diagnosis and treatment.

 

21. Cr: An inspection technique that uses an image board (IP) instead of an X-ray film as an imaging medium. Image Information on an IP address must be read and processed to display images.

 

22. DDR: digital X-ray imaging of flat panel detectors. Flat Panel detectors are used to convert X-ray signals into electrical signals and then digitize them to display image inspection techniques.

 

23. CT value: X-ray absorption coefficient of human tissue is converted to a numerical value to reflect the density of tissue with different absorption coefficients.

 

24. T1: The longitudinal relaxation time constant, which refers to the relaxation time experienced by the longitudinal Magnetization Vector recovering from the minimum value to the equilibrium state of 63%.

 

25. T2: The Transverse Relaxation Time Constant, which refers to the time taken by the transverse magnetization vector from the maximum attenuation to 37%. It is the scale to measure the transverse magnetization attenuation speed of the tissue.

 

26. MRA: a non-invasive angiogram technique used to display vascular and blood flow signal characteristics based on the characteristics of blood flow magnetic resonance imaging.

 

27. T1: T1 weighted imaging (MRI) mainly reflects the T1 feature parameters between tissues, reflecting the differences between T1, which is conducive to observing the anatomical structure.

 

28. T2: T2 weighted imaging refers to the imaging of MRI images that mainly reflect the T2 feature parameters between tissues, reflecting the differences between t2 between tissues, which is conducive to the observation of lesions.