Biomedical subjects

A V Barger

Publications and source records attributed to A V Barger.

2 recordsLinked to original sources

PubMed2000

Phase-contrast with interleaved undersampled projections.

MR phase-contrast techniques provide velocity-sensitive angiograms and quantitative flow measurements but require long scan times. Recently it has been shown that undersampled projection reconstruction can acquire higher resolution per unit time than Fourier techniques with acceptable artifacts when used in contrast-enhanced MR angiography. Undersampled projection reconstruction has similar potential for phase-contrast acquisitions. Flow sensitization gradients are used with projection trajectories to acquire velocity-dependent phase information. An acquisition scheme that acquires three flow encoding directions on three sets of angular-interleaved projections is introduced. Depending on the resolution, acquisition times for 3D datasets can decrease by factors of two to four.

Artifacts↗

PubMed2000

Single breath-hold 3D contrast-enhanced method for assessment of cardiac function.

Cardiac MRI function measurements are typically performed using 2D sequences and require multiple breath-holds to image the entire heart. A single 3D acquisition using a T(1)-shortening agent has many potential advantages over techniques that acquire multiple 2D images, including more consistent contrast and precise slice coverage. However, 3D techniques currently require much longer than a single breath-hold to complete. It has been shown that for MR angiography undersampled projection reconstruction can acquire much higher resolution per unit time than Fourier imaging with acceptable artifacts. By employing a gated, undersampled projection technique, high-resolution 3D multiphase volumes of the heart can be acquired in a single breath-hold. Short repetition times result in good myocardial suppression and a temporal aperture of 60 ms.

Contrast Media↗