PURPOSE To examine a new way of body diffusion weighted imaging (DWI) using the short TI inversion recovery-echo planar imaging (STIR-EPI) sequence and free breathing scanning (diffusion weighted whole body imaging with background body signal suppression; DWIBS) to obtain three-dimensional displays. MATERIALS AND METHODS 1) Apparent contrast-to-noise ratios (AppCNR) between lymph nodes and su...

Leaky-wave antennas use a traveling wave to radiate continuously along a radiating aperture in order to produce a focused beam of radiation. Planar leaky-wave antennas are particularly attractive since they use simple dielectric layers and/or metallic screens over a grounded substrate layer. A simple source such as a dipole or slot inside the substrate or on the ground plane excites the leaky w...

Planar accelerating structures, so called muffin tins, are of great interest for new accelerating techniques which are operating at high frequencies. At present the upper frequency limit for high power sources is 29.9855 GHz available at CERN. Therefore a new design of a planar traveling wave constant impedance accelerating structure is presented. A fully engineered 37-cell prototype with an op...

The use of spin-echoes has been employed in an Echo-Planar Spectroscopic Imaging (EPSI) sequence to collect multiple phase encoded lines within a single TR in a Multi-Echo-based Echo-Planar Spectroscopic Imaging technique (MEEPSI). Despite the T₂ dependence on the amplitude of the spin-echoes, the Full Width at Half Maximum (FWHM) of the derived multi-echo Point Spread Function (PSF) is shown t...

The cosine window function with the parameters optimized by Genetic Algorithm (GA) is applied in bistatic planar nearfield scattering measurements so as to effectively improve the measurement precision. With the infinitely long ideal conductor cylinder as the target under test, the bistatic planar near-field scattering measurement technique is studied by the method of computer simulation and so...

PURPOSE To improve the clinical utility of diffusion-weighted imaging (DWI) by extending the slice coverage of a high-resolution reduced field-of-view technique. THEORY Challenges in achieving high spatial resolution restrict the use of DWI in assessment of small structures such as the spinal cord. A reduced field-of-view method with 2D echo-planar radiofrequency (RF) excitation was recently ...

The modelling of the ultrasonic signals reflected from complex curved surfaces is a very complicated task. In order to simplify this task the reflectors are decomposed into multiple planar elements. Then the signals reflected by the planar areas and the areas between two planar elements oriented under some angle can be analysed separately. The objective of this study was verification of the aco...

The value of perfusion scintigraphy in the detection of pulmonary embolism (PE) was demonstrated as early as 1964 by Wagner et al. PE causes perfusion defects that conform to the anatomical distribution of the pulmonary vascular bed. Perfusion defects in acute PE are therefore of sub-segmental, segmental or lobar character. Ventilation is normally preserved in these areas and the observed wedge...

Terrestrial laser scanning systems have become widely available during the past years. Raw data acquired by such systems typically consists of separate overlapping datasets – each in its own local coordinate system. Applications that need data from more than a single scan position therefore must be preceded by a registration of all scans into a common geometric reference frame. In this paper, a...

INTRODUCTION: T2 imaging in the breast is most commonly performed using a fat suppressed 2D Fast Spin Echo (FSE) pulse sequence. The in-plane spatial resolution is high (<1mm) but the 3-4 mm slice thickness blurs fine structures and makes multi-planar reformatting sub-optimal. Balanced steady-state free precession (b-SSFP) techniques yield high SNR images in short scan times with a T2-like (T2/...