Conversely, a heavy (2.5-mm kernel size) smoothing may result in loss in spatial resolution (sharpness index) and image contrast (contrast-to-noise ratio).
Digital phantom studies were also performed to validate the system with the optimal square-hole collimator (23 mm hole length, 1.28 mm hole width, and 0.32 mm septal thickness) in terms of contrast, contrast-to-noise ratio and recovery ratio.
Therefore, we first modeled the effects of luminance (luminance-only model) and contrast (contrast-only model) separately, before assessing their unique effects in a model including them both (LumCon model).
Although contrast-enhanced MRI was preferred in the past for anatomic imaging due to fear of inducing an adrenal crisis with iodinated contrast, contrast-enhanced CT (using nonionic iodinated contrast) is now considered the best initial anatomic study with MRI reserved for problem solving.
The patterns we saw for these "all-scaffold" model conditions were mostly consistent with our first experiment, but also provide interesting contrasts (contrast Figure 7 to Figures 1 and 2).
In the planned treatment contrasts, contrast 1 (IH2 vs. IL2) was formally inestimable because, in the IL2 group, all data points were censored, that is, none of the 12 larvae remaining inside the domicile died.
We hypothesized that reduced cortical inhibition in migraine would result in decreased perceptual surround suppression on the contrast-contrast task, whereas, a general increased level of neural excitation would increase the effect of the surround on central responses.
In this study, we explore the balance between inhibition and excitation in migraine by measuring visual performance for a well-studied perceptual analogue of centre-surround neuronal responses: the Chubb illusion (also referred to as contrast-contrast suppression) [33].
