A comparison of conventional film, CR hard copy and PACS soft copy images of the chest: analyses of ROC curves and inter-observer agreement.

Study Objective: The aim of this study was to determine whether the accuracy of diagnosis of a spectrum of chest pathology was affected by the imaging technique used, and to compare conventional film/screen, hard copy computed (phosphor plate) radiography (CR) and soft copy CR (PACS) images.

Materials And Methods: For each of 44 patients who had a CT examination of the thorax, PA and lateral chest radiographs were produced using conventional film, hard copy CR and soft copy PACS images. Five radiologists independently scored all images for the presence of abnormalities.

Subvoxel image registration of multislice (2D) magnetic resonance images in patients with high-grade gliomas of the brain.

Aims: To implement a multislice two-dimensional (2D) T2-weighted sequence suitable for subvoxel image registration and to assess its usefulness in detecting change in high-grade intracranial gliomas.

Materials And Methods: Twenty patients with high-grade gliomas were studied on two or more occasions. T2-weighted multislice pulse sequences with a Gaussian slice profile, 50% overlapping slices and nearly isotropic voxels were acquired.

Magnetic resonance: magic angle imaging of the Achilles tendon.

Tendons do not normally produce detectable signals with conventional magnetic-resonance techniques and are recognised as dark signal voids. However, if tendons are examined at 55 degrees to the static magnetic field (the "magic angle"), signals become detectable and the tendons can become the brightest structure on the image. We have used this approach to establish tendon relaxation times and magnetisation transfer ratios and to show contrast enhancement.

FLAIR imaging using nonselective inversion pulses combined with slice excitation order cycling and k-space reordering to reduce flow artifacts.

High-signal artifacts produced by cerebrospinal fluid (CSF) flow can adversely affect fluid-attenuated inversion recovery (FLAIR) imaging of the brain and spinal cord. This study explores the use of a nonslice-selective inversion pulse to eliminate CSF flow artifacts together with a technique called "K-space Reordered by Inversion-time for each Slice Position" (KRISP) to achieve constant contrast in a multislice acquisition. Theory shows that with this method the CSF point spread function (PSF) has a minimum at the center and attenuated side lobes, providing CSF suppression, but residual edge signals remain.

MRI changes in multiple sclerosis following treatment with lofepramine and L-phenylalanine.

As part of a large, randomized placebo-controlled trial of inpatients with multiple sclerosis (MS), a subsample of 15 underwent cerebral MRI at baseline and 6-months (eight on lofepramine and l-phenylalanine; seven on placebo). Unlike the placebo group, the active group showed a significant reduction in lesion number visible on T1-weighted scans (p < 0.05).