Search results
Results From The WOW.Com Content Network
Perfusion MRI or perfusion-weighted imaging (PWI) is perfusion scanning by the use of a particular MRI sequence [which? The acquired data are then post-processed to obtain perfusion maps with different parameters, such as BV (blood volume), BF (blood flow), MTT (mean transit time) and TTP (time to peak).
Ventilation/perfusion scans, sometimes called a VQ (V=Ventilation, Q=perfusion) scan, is a way of identifying mismatched areas of blood and air supply to the lungs. It is primarily used to detect a pulmonary embolus. The perfusion part of the study uses a radioisotope tagged to the blood which shows where in the lungs the blood is perfusing.
In CT perfusion, a contrast media injection is given, and then the scan is taken. The acquired data are post-processed to obtain perfusion maps with different parameters, such as BV (blood volume), BF (blood flow), MTT (mean transit time), and TTP (time to peak).
CT Perfusion scan of the brain. CT perfusion imaging is a specific form of CT to assess flow through blood vessels whilst injecting a contrast agent. [21] Blood flow, blood transit time, and organ blood volume, can all be calculated with reasonable sensitivity and specificity. [21]
The two scanners are located in the same machine, but they do not perform scans at the same time. A CT scan is typically done first, followed by a PET scan. [22] For cardiac scans, combining CT cardiac data with PET metabolic or perfusion data from PET/CT machines may be of clinical value.
MRI does not involve X-rays or the use of ionizing radiation, which distinguishes it from computed tomography (CT) and positron emission tomography (PET) scans. MRI is a medical application of nuclear magnetic resonance (NMR) which can also be used for imaging in other NMR applications, such as NMR spectroscopy. [1]
Diffusion imaging is an MRI method that produces in vivo magnetic resonance images of biological tissues sensitized with the local characteristics of molecular diffusion, generally water (but other moieties can also be investigated using MR spectroscopic approaches). [15] MRI can be made sensitive to the motion of molecules.
Computed tomography (CT) perfusion imaging; Functional magnetic resonance imaging (fMRI) BOLD; Diffusion MRI; Perfusion (blood flow) Arterial spin labeling MRI; Blood volume; Hyperpolarized carbon-13 MRI; Functional photoacoustic microscopy (fPAM) Magnetic particle imaging (MPI) Optical imaging. Near-infrared spectroscopy (NIRS)