Gadolinium pharmacokinetics of chronic myocardial infarcts: Implications for late gadolinium-enhanced infarct imaging.

Purpose: To monitor gadolinium pharmacokinetics in the hearts of patients with chronic myocardial infarcts and to determine the variability of contrast agent concentrations and accuracy of infarct detection over an hour time period.

Materials And Methods: Twenty-five patients with chronic myocardial infarcts were examined. T1 measurements were performed every 2 minutes using an inversion recovery CINE balanced steady-state free precession technique.

Recent myocardial infarction: assessment with unenhanced T1-weighted MR imaging.

The purpose of the study was to prospectively evaluate a T1-weighted technique for detection of myocardial edema resulting from recent myocardial infarction (MI) or intervention. This study was HIPAA compliant and institutional review board approved. Fifteen men and one woman (mean age, 57.

T1-weighted magnetic resonance imaging shows fatty deposition after myocardial infarction.

Pathologic studies have shown an increased lipid content in areas of myocardial infarction (MI). We sought to show the ability of precontrast T1-weighted MRI to noninvasively detect fat deposition in MI and show its association with infarct age. Thirty-two patients with MI were studied.

On the cause of spatial displacement of long T1 species in segmented inversion recovery prepared imaging.

Using inversion recovery steady-state free precession segmented k-space imaging for the detection of myocardial infarction, we noticed that some structures appeared in the wrong locations of the image. In this work, the spatial displacement is demonstrated and explained from both theoretical and experimental points of view. The effect is due to a change in phase from segment to segment of the detected magnetization from species with long T1's such as cysts, fluid collections, and cerebrospinal fluid.

Adaptation of the attention network in human immunodeficiency virus brain injury.

Human immunodeficiency virus (HIV)-positive patients commonly have attention and concentration problems. However, it remains unclear how HIV infection affects the attention network. Therefore, blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) was performed in 36 subjects (18 HIV and 18 seronegative [SN] controls) during a set of visual attention tasks with increasing levels of attentional load.

k-Space based summary motion detection for functional magnetic resonance imaging.

Functional MRI studies are very sensitive to motion; head movements of as little as 1-mm translations or 1 degrees rotations may cause spurious signals. An algorithm was developed that uses k-space MRI data to monitor subject motion during functional MRI time series. A k-space weighted average of squared difference between the initial scan and subsequent scans is calculated, which summarizes subject motion in a single quality parameter; however, the quality parameter cannot be used for motion correction.