Ad
related to: spatial vs contrast resolution radiology journal articles pdf
Search results
Results From The WOW.Com Content Network
Contrast resolution or contrast-detail is an approach to describing the image quality in terms of both the image contrast and resolution. Contrast resolution is usually measured by generating a pattern from a test object that depicts how image contrast changes as the structures being imaged get smaller and closer together.
An article from the heart center in Leipzig suggests that intraoperative 3D imaging with rotational angiography is much more precise and can be performed with low contrast and low radiation dose if combined with diluted contrast injection and rapid ventricular pacing. They found measurements performed on this 3D image highly reliable.
Spatial resolution is typically expressed in line pairs per millimeter (lppmm), lines (of resolution, mostly for analog video), contrast vs. cycles/mm, or MTF (the modulus of OTF). The MTF may be found by taking the two-dimensional Fourier transform of the spatial sampling function. Smaller pixels result in wider MTF curves and thus better ...
The detective quantum efficiency (often abbreviated as DQE) is a measure of the combined effects of the signal (related to image contrast) and noise performance of an imaging system, generally expressed as a function of spatial frequency. This value is used primarily to describe imaging detectors in optical imaging and medical radiography.
This explains why the images for the out-of-focus system (e,f) are more blurry than those of the diffraction-limited system (b,c). Note that although the out-of-focus system has very low contrast at spatial frequencies around 250 cycles/mm, the contrast at spatial frequencies near the diffraction limit of 500 cycles/mm is diffraction-limited.
Conventional qualitative interpretation of Fourier Analysis asserts that low spatial frequencies (near the center of k-space) contain the signal to noise and contrast information of the image, whereas high spatial frequencies (outer peripheral regions of k-space) contain the information determining the image resolution.
MRI has the advantages of having very high spatial resolution and is very adept at morphological imaging and functional imaging. MRI does have several disadvantages though. First, MRI has a sensitivity of around 10 −3 mol/L to 10 −5 mol/L which, compared to other types of imaging, can be very limiting. This problem stems from the fact that ...
Spatial resolution is, in many cases, essentially given by the detector pixel size. The technique of sequential topography, in combination with appropriate data analysis methods also called rocking curve imaging , constitutes a method of microdiffraction imaging , i.e. a combination of X-ray imaging with X-ray diffractometry .