A traditional solution of area-based stereo uses some kind of windowed pixel intensity correlation. This approach suffers from discretization artifacts which corrupt the correlation value. We introduce a new correlation statistic, which is completely invariant to image sampling, moreover it naturally provides a position of the correlation maximum between pixels. Hereby we can obtain sub-pixel d...

SummaryBackground: Pressure reactivity index (PRx)-cerebral perfusion pressure (CPP) relationships over a given time period can be used to detect value of CPP at which PRx shows the best autoregulation (optimal CPP, or CPPopt). Algorithms for continuous assessment CPPopt in traumatic brain injury (TBI) patients reached desired high yield with multi-window approach (CPPopt_MA). However, calculat...

Objective(s): Use of a positron emission tomography (PET)/single-photonemission computed tomography (SPECT) system facilitates the simultaneousacquisition of images with fluorine-18 fluorodeoxyglucose (18F-FDG) andtechnetium (99mTc)-tetrofosmin. However, 18F has a short half-life, and 511keV Compton-scattered photons are detected in the 99mTc energy window.Therefore, in this study, we aimed to ...

PURPOSE To correct gradient-induced phase errors in radial MRI. METHODS Gradient-induced eddy currents affect the MRI data acquisition by gradient delays and phase errors that may lead to severe image artifacts for non-Cartesian imaging scenarios such as radial trajectories. While gradient delays are dealt with by respective shifts of the acquisition window during radial image acquisition, th...

An efficient filter structure which can generate any window of a linearly predictable signal is presented. As special cases, this includes e.g. the polynomial, weighted exponential and Hamming-window responses. The structure can be applied in the efficient implementation of predictive filters with minimal noise gain.

PURPOSE Patient-specific dosimetry of lutetium-177 ((177)Lu)-DOTATATE treatment in neuroendocrine tumours is important, because uptake differs across patients. Single photon emission computer tomography (SPECT)-based dosimetry requires a conversion factor between the obtained counts and the activity, which depends on the collimator type, the utilized energy windows and the applied scatter corre...

In this paper, we propose a census transform-based fast stereo algorithm. Most conventional fast stereo algorithms are based on SAD (Sum of Absolute Difference) or NC (Normalized Correlation). However, SAD is often sensitive to noise or illumination changes. Image matching by census transform is known to be robust to radiometric distortion, since the differences in gain and bias between two ima...

This paper presents a method to compute Mean and Gaussian curvatures from range images. The rst and second partial derivatives are estimated by the weighted least squares t of a biquadratic polynomial within a local moving window. The weights are determined on the basis of surface distances and normal angular distances from the center points of the window.

Figure 3 (right) – Comparison of ky-onlyand ky-kz-reordered scans with 100% data acceptance and with a 4mm navigator window. Figure 1 (above) – Diagram illustrating the radial reordering process. Vertical axis is ky, horizontal axis is kz and color represents calculated radius in the top part of the figure. The bottom part of the figure shows the navigator signal and the respiratory gating wind...

There has been conflicting data in the literature regarding the use of wide navigator echo (NE) acceptance windows in combination with adaptive motion correction for magnetic resonance coronary angiography (MRCA). This in part may be due to the use of a fixed correction factor when applying the adaptive motion-correction algorithm, which may potentially result in miscorrection of the imaging sl...