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Grayscale contrast enhancement based on greyscale-based contrast-to-noise ratio
Medical Imaging 2021: Image Perception, Observer Performance, and Technology Assessment, 2021Subjective reading is still the majority way in current medical image diagnostics, and the visualization effect of images is one important factor which may affect the reading performance or diagnostic quality. In computed tomography (CT), CT numbers are converted into greyscale images by the display window settings.
Wei Zhou +3 more
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Generalized contrast-to-noise ratio as a metric of photoacoustic image quality
Photons Plus Ultrasound: Imaging and Sensing 2021, 2021Multiple image quality metrics are currently available to assess target detectability in photoacoustic images. Common metrics include contrast, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR). The generalized contrast-to-noise ratio (gCNR) is a relatively new image quality metric to assess the probability of photoacoustic target ...
Kelley M. Kempski +4 more
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Maximizing signal-to-noise and contrast-to-noise ratios in flash imaging
Magnetic Resonance Imaging, 1987This paper presents an analysis of signal-to-noise and contrast-to-noise ratios from small tip angle, gradient reversal (FLASH) imaging. Analytic and numerical techniques are used to determine the delay times and tip angles that maximize signal-to-noise per unit time from a single tissue. Similar procedures are used to determine the delay times and tip
R E, Hendrick, J B, Kneeland, D D, Stark
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Maximization of contrast‐to‐noise ratio to distinguish diffusion and microcirculatory flow
Journal of Magnetic Resonance Imaging, 1991AbstractOptimization of the contrast‐to‐noise ratio (CNR) is described for microcirculation magnetic resonance (MR) imaging techniques based on flow‐compensated/flow‐dephased sequences, both with and without even‐echo rephasing. The authors present the most advantageous manner of applying flow‐dephased gradients, such that de‐phasing is maximal while ...
J H, Maki +3 more
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Theoretical predictions of the generalized contrast-to-noise ratio for photoacoustic images
2020 IEEE International Ultrasonics Symposium (IUS), 2020Target detectability in photoacoustic imaging applications is traditionally analyzed using image quality metrics, such as signal-to-noise ratio, contrast, and contrast-to-noise ratio. These metrics are difficult to interpret in the context of target detectability due to their lack of an upper bound and their sensitivity to image manipulation techniques
Mardava R. Gubbi +1 more
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Blind Estimation for Localized Low Contrast-to-Noise Ratio BOLD Signals
IEEE Journal of Selected Topics in Signal Processing, 2008Accurate detection of low contrast-to-noise ratio (CNR) blood oxygenation level dependent (BOLD) signals in functional magnetic resonance imaging (fMRI) data is important for presurgical planning and cognitive research. Robust detection is challenging in small regions of low CNR activation since the probability of detecting each individual voxel is low.
Ian C. Atkinson +3 more
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Improving the contrast-to-noise ratio by averaging in scintillation detectors
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016From the point of view of the image quality, the contrast-to-noise ratio (CNR) is a crucial parameter. In case of the scintillation detectors, which are widely used in X-ray radiography and computed tomography, CNR is determined by the static image noise caused mainly by the non-uniformity of the response of particular pixels, and by the stochastic ...
Michal Vopalensky +2 more
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Contrast-to-noise ratio optimization for a prototype phase-contrast computed tomography scanner
Review of Scientific Instruments, 2015In the field of biomedical X-ray imaging, novel techniques, such as phase-contrast and dark-field imaging, have the potential to enhance the contrast and provide complementary structural information about a specimen. In this paper, a first prototype of a preclinical X-ray phase-contrast CT scanner based on a Talbot-Lau interferometer is characterized ...
Mark Müller +8 more
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Measurement of contrast-to-noise ratio for differential phase contrast computed tomography
SPIE Proceedings, 2010Differential phase contrast imaging has recently been demonstrated using both synchrotron and conventional xray sources with a grating interferometer. This approach offers the possibility of simultaneous CT reconstructions of both absorption and index of refraction from a single acquisition.
Joseph Zambelli +3 more
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Dual energy contrast enhanced breast imaging optimization using contrast to noise ratio
SPIE Proceedings, 2007The properties of dual energy contrast enhanced breast imaging have been analyzed by imaging a 4 cm breast equivalent phantom consisting of adipose and glandular equivalent plastics. This phantom had superimposed another thin plastic which incorporated a 2 mm deep cylinder filled with iodinated contrast media.
C. D. Arvanitis, G. Royle, R. Speller
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