MP RAGE: a three-dimensional, T1-weighted, gradient-echo sequence--initial experience in the brain.

Abstract

The authors evaluated a recently developed sequence for magnetic resonance imaging of the brain. The three-dimensional, Fourier-transformed acquisitions require magnetization-prepared 180 degrees radio-frequency pulses and rapid gradient-echo (MP RAGE) sampling. The resulting T1-weighted images were compared with T1-weighted spin-echo (SE) images; both were obtained after paramagnetic contrast material was administered to 33 patients with known or suspected focal brain lesions. Image quality and contrast between gray and white matter were superior with the MP RAGE sequence compared with the T1-weighted SE sequence. The time for obtaining contiguous thin-section (1.3-2.5-mm) images was also comparable, with readily acquired multiplanar reformations obviating additional images. MP RAGE imaging depicted more focal lesions than did T1-weighted SE imaging and matched the number seen with T2-weighted SE imaging. Demonstration of paramagnetic contrast enhancement of lesions was comparable in most cases; however, three lesions showed greater enhancement on T1-weighted SE images and two others were seen only on the T1-weighted SE images. Thus, the MP RAGE sequence may provide an alternative to T1-weighted SE imaging.

Transient and sustained components of the sensorimotor BOLD response in fMRI

“…A T1-weighted anatomical scan was acquired using the magnetization prepared 180° radiofrequency pulses and rapid gradientecho [30] sequence with repetition time (TR)/echo time (TE)/flip/field of view (FOV)/ matrix/bandwidth of 2 s/2.63 s/9°/25.6 cm/256×192/ 180 Hz/pixel in 6/8 partial Fourier mode. To improve the fitting performance of the GLM regression, temporal sampling of the BOLD time course was increased at the cost of a reduced FOV.…”

The morphology of articular cartilage assessed by magnetic resonance imaging (MRI)

“…MPRAGE, a Tl-weighted gradient-echo sequence [3] that can be optimized for the delineation of articular cartilage [29], does not seem to improve the demonstration of cartilage thickness. The articular surface and the cartilage volume were significantly underestimated.…”

Contrast-enhanced, three-dimensional, whole-brain, black-blood imaging: Application to small brain metastases

“…Among them, CE T 1 -weighted two-dimensional spin echo (SE) imaging has gained widespread clinical acceptance for the detection of brain tumors with permeable vessels, providing high signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), but has limitations in detecting the small size of metastases due to partial-volume effects. To overcome this problem, magnetizationprepared rapid-gradient-echo (MP-RAGE) imaging (7,8), which is the most widely used three-dimensional (3D) T 1 -weighted imaging sequence, can be used to acquire high-resolution, isotropic whole-brain data in a clinically acceptable imaging time. Despite these advantages, a potential confound is the distribution of contrast agents within blood vessels and the tumor parenchyma resulting in the simultaneous enhancement of both regions, thereby impairing the accuracy of metastatic lesion detection.…”