What is diffusion weighted MRI imaging?
Diffusion-weighted imaging (DWI) is a form of MR imaging based upon measuring the random Brownian motion of water molecules within a voxel of tissue. In general simplified terms, highly cellular tissues or those with cellular swelling exhibit lower diffusion coefficients.
What is whole body diffusion MRI?
Whole-body diffusion-weighted magnetic resonance imaging (WB-DWI-MRI) is an emerging tool that has an increasing role in the diagnosis of metastasis and lymphoma. This is a longitudinal study in actual clinical settings designed to assess WB-DWI-MRI in detection of tumor spread.
What does diffusion weighted imaging measure?
Diffusion weighted imaging (DWI) is based on measuring the Brownian motion of water molecules, which is restricted in highly cellular tissue such as tumor tissue compared with water motion in normal and low cellular benign tissue.
What does Diffusion MRI measure?
Diffusion MRI (dMRI) is a MRI method that measures molecular diffusion in biological tissues. As molecules interact with many different obstacles as they diffuse throughout tissues, dMRI provides insight into the microscopic details of tissue architecture.
What is diffusion weighted?
Diffusion weighted imaging (DWI) is a method of signal contrast generation based on the differences in Brownian motion. DWI is a method to evaluate the molecular function and micro-architecture of the human body.
What is magnetic resonance spectroscopy used for?
Magnetic resonance spectroscopy (MRS), also known as nuclear magnetic resonance (NMR) spectroscopy, is a non-invasive analytical technique that has been used to study metabolic changes in brain tumors, strokes, seizure disorders, Alzheimer’s disease, depression and other diseases affecting the brain.
HOW IS MR spectroscopy performed?
MR spectroscopy is conducted on the same machine as conventional MRI. The MRI scan uses a powerful magnet, radio waves, and a computer to create detailed images. Spectroscopy is a series of tests that are added to the MRI scan of your brain or spine to measure the chemical metabolism of a suspected tumor.
What are weighted images?
T1 weighted image (also referred to as T1WI or the “spin-lattice” relaxation time) is one of the basic pulse sequences in MRI and demonstrates differences in the T1 relaxation times of tissues. A T1WI relies upon the longitudinal relaxation of a tissue’s net magnetization vector (NMV).
What is called diffusion?
diffusion, process resulting from random motion of molecules by which there is a net flow of matter from a region of high concentration to a region of low concentration.
How does diffusion imaging work?
In simplified terms, diffusion imaging works by introducing extra gradient pulses whose effect “cancels out” for stationary water molecules, and causes a random phase shift for molecules that diffuse. Due to their random phase, signal from diffusing molecules is lost.
What is magnetic resonance?
Magnetic resonance imaging (MRI) is a medical imaging technique that uses a magnetic field and computer-generated radio waves to create detailed images of the organs and tissues in your body. Most MRI machines are large, tube-shaped magnets.
What are the types of magnetic resonance?
Types of Magnetic Resonance Imaging (MRI) Exams
- Functional MRI (fMRI)
- Breast scans.
- Magnetic resonance angiography (MRA)
- Magnetic resonance venography (MRV)
- Cardiac MRI.