Helpful Terms
DICOM
DICOM (or Digital Imaging and Communications in Medicine) is a standard developed by the American College of Radiology and the National Electrical Manufacturers Association. “DICOM-compatibility” simply means that different users of different imaging devices will be able to smoothly exchange information. (More info at http://medical.nema.org)
BIT DEPTH
Bit depth is a computer graphics term describing the number of bits used to represent the color of a single pixel in a bitmapped image or video frame buffer. Higher color depth gives a broader range of distinct colors.
Bit DepthShades of Grey
01
12
24
38
416
532
664
8128
10256
12512
141024
162048
DR
Direct digital radiography (DR) is based on CCD (Charge Couple Device) technology, but it is much faster. Like CCD, DR systems rely on a phosphor-like material, also known as a scintillator, to capture the x-rays. Rather than forming a latent image, DR images light up immediately. An extremely sensitive camera, more like the Hubble space telescope than your digital camera, records the light, digitizes it and sends it to the computer in seconds.
GRID RATIO
When a radiograph is taken, some of the x-rays are scattered. A grid, which is a thin plate made up of alternating thin strips of lead and plastic, can be placed between the animal and the film to reduce the scattered x-rays from exposing the film. The ability of a grid to remove scattered radiation is measured by the grid ratio. The grid ratio is determined by the height of the lead strips divided by the distance between them.
kVp
Kilovoltage potential (kVp) is the highest potential voltage achieved at a certain kV setting. High kVp techniques are most useful for studies of body regions with many different tissue densities. Higher kVp techniques are appropriate for larger and thicker animals. Increasing kV is not a linear function, and small increases in kVp settings may substantially increase the number of x-rays penetrating the animal. However, this effect is much less dramatic above 85 kVp.