Functional imaging (or physiological imaging) is a
medical imaging technique of detecting or measuring changes in
metabolism
Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the co ...
, blood flow, regional chemical composition, and absorption.
As opposed to structural imaging, functional imaging centers on revealing
physiological activities within a certain tissue or organ by employing medical image modalities that very often use
tracers or probes to reflect spatial distribution of them within the body. These tracers are often
analogous to some chemical compounds, like glucose, within the body. To achieve this, isotopes are used because they have similar chemical and biological characteristics. By appropriate proportionality, the
nuclear medicine physicians can determine the real intensity of certain substances within the body to evaluate the risk or danger of developing some diseases.
Modalities
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Positron emission tomography (PET)
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Fludeoxyglucose for Glucose metabolism
** O-15 as a flow tracer
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Single-photon emission computed tomography (SPECT)
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Computed tomography (CT) perfusion imaging
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Functional magnetic resonance imaging
Functional magnetic resonance imaging or functional MRI (fMRI) measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area o ...
(fMRI)
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BOLD
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Diffusion MRI
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Perfusion (blood flow)
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Arterial spin labeling MRI
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Blood volume
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Hyperpolarized carbon-13 MRI
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Functional photoacoustic microscopy (fPAM)
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Magnetic particle imaging
Magnetic particle imaging (MPI) is an emerging non-invasive Tomography, tomographic technique that directly detects Superparamagnetic Iron Oxide Nanoparticles, superparamagnetic nanoparticle tracers. The technology has potential applications in dia ...
(MPI)
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Optical imaging
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Near-infrared spectroscopy (NIRS)
See also
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Biomedical engineering
Biomedical engineering (BME) or medical engineering is the application of engineering principles and design concepts to medicine and biology for healthcare applications (e.g., diagnostic or therapeutic purposes). BME also integrates the logica ...
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Medical imaging
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PET-CT
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Radiology
Radiology ( ) is the medical specialty that uses medical imaging to diagnose diseases and guide treatment within the bodies of humans and other animals. It began with radiography (which is why its name has a root referring to radiation), but tod ...
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Functional neuroimaging
Functional neuroimaging is the use of neuroimaging technology to measure an aspect of brain function, often with a view to understanding the relationship between activity in certain brain areas and specific mental functions. It is primarily used a ...
References
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External links
Scholarpedia Functional imaging Medical imaging