64 articles
Magnetization transfer imaging
Magnetization transfer imaging is an MRI technique, introduced by Wolff and Balaban in 1989, that measures macromolecular content such as myelin and is mainly applied to multiple sclerosis.
Magnetization transfer MRI
Magnetization transfer MRI is an MRI technique that uses off-resonance radiofrequency pulses to probe invisible macromolecular protons, providing one of the main measures of myelin content in vivo.
Magnetization-prepared rapid gradient echo MRI
Magnetization-prepared rapid gradient echo (MPRAGE, also written MP-RAGE) is a 3D MRI pulse sequence producing high-resolution T1-weighted brain volumes, widely used clinically since its 1990 introduction.
MR elastography
MR elastography (MRE) is an MRI technique that measures soft tissue stiffness in kilopascals by imaging shear waves from mechanical vibration, and is a clinical standard for staging liver fibrosis.
Multiparametric magnetic resonance imaging
Multiparametric MRI (mpMRI) combines several MRI sequences, typically T2-weighted anatomy with diffusion-weighted and dynamic contrast-enhanced imaging, and is the standard for diagnosing clinically significant prostate cancer.
Myelin water imaging
Myelin water imaging (MWI) is an MRI technique that measures the fraction of tissue water trapped within myelin sheaths, giving a specific index of myelin content.
Myocardial T1 mapping
Myocardial T1 mapping is a cardiac magnetic resonance technique that measures T1 relaxation times of heart muscle pixel by pixel, detecting fibrosis, edema, and infiltrative disease that late gadolinium enhancement can miss.
Parallel imaging (MRI)
Parallel imaging is an MRI acceleration technique that uses receiver coils with different spatial sensitivities to reduce scan time, with SENSE and GRAPPA the main reconstruction methods.
Parametric magnetic resonance imaging
Parametric magnetic resonance imaging is a medical imaging approach that maps relaxation times such as T1, T2, and T2 pixel by pixel in absolute units, detecting diffuse disease conventional MRI misses.
Perfusion Magnetic Resonance Imaging
Perfusion MRI measures capillary-level blood delivery (ml/100 g/min) using four techniques: DSC and DCE with gadolinium contrast, and non-contrast ASL and IVIM; used for stroke, brain tumors, and dementia.
Phase-contrast magnetic resonance imaging
Phase-contrast magnetic resonance imaging, also known as phase-contrast MRI, is an MRI technique that measures blood flow noninvasively by encoding fluid velocity into the signal phase.
Proton magnetic resonance spectroscopy
Proton magnetic resonance spectroscopy is an MRI technique measuring hydrogen signals from metabolites in tissue instead of water, used to diagnose brain and prostate tumors through characteristic metabolite changes.
Pseudo-continuous arterial spin labeling
Pseudo-continuous arterial spin labeling (pCASL) is an MRI technique that labels arterial blood water with radiofrequency pulses to map brain blood flow without contrast agents, recommended for clinical use.
Quantitative magnetic resonance imaging
Quantitative magnetic resonance imaging (qMRI) is a family of MRI techniques that measure tissue properties such as relaxation times and diffusion as numerical values in physical units.
Quantitative susceptibility mapping
Quantitative susceptibility mapping (QSM) is an MRI post-processing technique that converts gradient-echo phase images into maps of tissue magnetic susceptibility, quantifying iron, hemorrhage, and calcification.
Real-time MRI
Real-time MRI is magnetic resonance imaging fast enough to capture moving structures, such as the beating heart or vocal tract during speech, as a continuous movie without breath-holding or ECG gating.
Sensitivity encoding (MRI)
Sensitivity encoding (SENSE) is a parallel MRI technique, introduced in 1999 by Pruessmann and colleagues, that uses receiver coil sensitivities to shorten scan times and remains widely used clinically.
Single-voxel spectroscopy
Single-voxel spectroscopy (SVS) is a magnetic resonance spectroscopy technique that acquires a metabolite spectrum from one small, precisely defined tissue volume, applied mostly to the brain.
Steady-state free precession imaging
Steady-state free precession (SSFP) is an MRI pulse sequence that uses rapid repeated radiofrequency pulses to maintain steady transverse magnetization, producing high-signal images with bright-fluid contrast.
Susceptibility weighted imaging
Susceptibility weighted imaging (SWI) is an MRI technique using phase images to highlight blood, iron, and calcium, developed from 1997 venography work by Reichenbach and Haacke.
T1-weighted imaging
T1-weighted imaging is a magnetic resonance imaging technique in which tissue contrast is set mainly by T1 relaxation times, with fat bright, fluids dark, and gadolinium contrast agents best seen.
T1-weighted MRI
T1-weighted MRI, also known as 3D T1-weighted MRI, is a magnetic resonance imaging technique whose contrast is set by T1 relaxation times, making fat bright and water-rich tissue dark.
T2 mapping
T2 mapping is an MRI technique that converts tissue T2 relaxation times into pixel-by-pixel maps, used to measure heart muscle edema and knee cartilage degeneration.
T2 relaxometry
T2 relaxometry is a quantitative MRI technique measuring tissue T2 relaxation times in milliseconds instead of contrast images, used for myocardial edema, iron overload, myelin, and cartilage.
T2-weighted FLAIR MRI
T2-weighted FLAIR MRI is an MRI sequence that suppresses cerebrospinal fluid signal so white matter lesions, edema, and subarachnoid blood stand out, notably in multiple sclerosis.
T2-weighted MRI
T2-weighted MRI is a magnetic resonance imaging technique using long repetition and echo times so that fluid, edema, and many lesions appear bright against darker solid tissue.
Three-dimensional magnetic resonance imaging
Three-dimensional magnetic resonance imaging (3D MRI) excites a slab of tissue as a whole and reconstructs a continuous block of voxels rather than separate slices, allowing reformatting in arbitrary orientations.
Time-dependent diffusion MRI
Time-dependent diffusion MRI (TDDMRI or TDD-MRI) is a diffusion MRI technique that varies diffusion time to map microstructure like cell size and density, used mainly in oncology.
Ultra-low-field MRI
Ultra-low-field MRI (ULF MRI) is magnetic resonance imaging at field strengths far below conventional clinical scanners, trading image resolution for lower cost, portability, and use outside shielded rooms.
Ultrafast MRI
Ultrafast MRI is a magnetic resonance imaging technique that acquires images in tens of milliseconds to a few minutes, enabling sedation-free pediatric scans and stroke triage.