IEEE Transactions on Medical Imaging

Dual-energy imaging provides images in which the conspicuity of the signal of interest is heightened by selectively cancelling intervening structures. Area detectors for dual-energy imaging offer some advantages over line-scanning systems because they make efficient use of the source. Area detectors, however, collect scattered radiation. To determine the seriousness of the scatter problem and how ... View full abstract»

A method that incorporates a priori uniform or nonuniform source distribution probabilistic information and data fluctuations of a Poisson nature is presented. The source distributions are modeled in terms of a priori source probability density functions. Maximum a posteriori probability solutions, as determined by a system of equations, are given. Interactive Bayesian imaging algorithms for the s... View full abstract»

An image registration technique for application in X-ray, gamma-ray, and magnetic resonance imaging is described. The technique involves searching a real-valued, multidimensional, rectangular, symmetric space of bilinear geometrical transformations for a globally optimal transformation. Physical considerations provide theoretical limits on the search space, but the theoretically maximum allowable ... View full abstract»

The ANALYZE software system, which permits detailed investigation and evaluation of 3-D biomedical images, is discussed. ANALYZE can be used with 3-D imaging modalities based on X-ray computed tomography, radionuclide emission tomography, ultrasound tomography, and magnetic resonance imaging. The package is unique in its synergistic integration of fully interactive modules for direct display, mani... View full abstract»

The type of radio-frequency (RF) coil known as a high-pass birdcage consists of a set of N wires arranged axially on the surface of a cylinder and connected by capacitors at each end. Such coils are widely used for NMR imaging because of the high degree of field homogeneity they provide. It is shown how to create homogeneous fields at two frequencies, using an unequal distribution of capa... View full abstract»

A method of compensating for the lag of the video cameras typically used in angiographic systems is presented for use in sequences of digitized X-ray images. The lag effect is reduced by a straightforward weighted subtraction, which has the undesirable side effect of increasing noise. By superimposing several lag-corrected and appropriately shifted images, however, the signal-to-noise ratio can be... View full abstract»

An approach to image analysis and processing, called holospectral imaging, is proposed for dealing with Compton scattering contamination in nuclear medicine imaging. The method requires that energy information be available for all detected photons. A set of frames (typically 16) representing the spatial distribution at different energies is then formed. The relationship between these energy frames... View full abstract»

Blood vessels usually have poor local contrast, and the application of existing edge detection algorithms yield results which are not satisfactory. An operator for feature extraction based on the optical and spatial properties of objects to be recognized is introduced. The gray-level profile of the cross section of a blood vessel is approximated by a Gaussian-shaped curve. The concept of matched f... View full abstract»

A method used to provide gain variation with received echo range to compensate for tissue attenuation in standard B-mode ultrasound imaging systems achieves signal multiplication by first logarithmically compressing the complete dynamic range of the received echo. The time-gain correction method described here is a modification of this method. It performs the time-gain correction operatio... View full abstract»

At present, the diagnosis of cardiac left ventricular regional wall motion abnormalities (RWMA) in nuclear medicine is aided mainly by phase images and amplitude images, which picture the spatial distribution of the phase and of the amplitude of the first harmonics of pixel time activity curves, respectively. However, they do not utilize other information contained in the original radionuclide ima... View full abstract»