Quantitative Mri
Quantitative Mri - Related Videos
15:10
A Dual Tracer PET-MRI Protocol for the Quantitative Measure of Regional Brain Energy Substrates Uptake in the Rat
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Cited by 2 •
2013
Small-animal positron emission tomography enables the assessment of the brain's two main energy substrates: glucose and ketones. In the present method, 11C-acetoacetate and 18F-fluorodeoxyglucose are injected sequentially in each animal, and their uptake is measured quantitatively in specific brain regions determined from the magnetic resonance images.
06:06
Optogenetic Functional MRI
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Cited by 15 •
2016
This protocol describes the steps and data analysis required to successfully perform optogenetic functional magnetic resonance imaging (ofMRI). ofMRI is a novel technique that combines high-field fMRI readout with optogenetic stimulation, allowing for cell type-specific mapping of functional neural circuits and their dynamics across the whole living brain.
12:27
Noninvasive In Vivo Small Animal MRI and MRS: Basic Experimental Procedures
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Cited by 9 •
2009
This work describes basic procedures of noninvasive small animal MRI and MRS in vivo.
08:20
MRI-guided dmPFC-rTMS as a Treatment for Treatment-resistant Major Depressive Disorder
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Cited by 31 •
2015
Here we outline the procedure for MRI-guided repetitive transcranial magnetic stimulation to the dorsomedial prefrontal cortex as an experimental treatment for major depressive disorder.
06:58
Synthesis of an In vivo MRI-detectable Apoptosis Probe
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Cited by 3 •
2012
Early detection of apoptosis may identify at-risk cell populations in a variety of diseases. Here we demonstrate a method to link an early apoptosis-detection protein (Annexin V) to a MRI-detectable iron oxide nanoparticle (SPIO). This method may be extended to other proteins of interest to generate MRI-detectable molecular imaging probes.
FAQs
Controlled changes in repetition time or echo time produce multiple measurements of the same tissue signal under different conditions. qMRI then examines how that signal changes across the acquisition rather than relying on one image appearance. Fitting the observed behavior to a relaxation or related model converts those changes into numerical estimates that can be compared across regions or examinations.
A signal model links measured changes in MRI signal to a property of the tissue. During analysis, the acquired values are fitted to that model, allowing the resulting map to represent a measurable characteristic rather than an unprocessed signal intensity. This modeling step makes the measurements interpretable and supports consistent numerical comparisons between tissue regions or examinations.
Conventional MRI primarily supports visual assessment of anatomy, whereas qMRI adds numerical measurements derived from signal behavior. That distinction can make tissue differences easier to express as measurable values instead of descriptive appearance alone. In research and medicine, the resulting numbers can support comparisons across patients or time points, complementing rather than replacing image interpretation.
The workflow starts by acquiring MRI data with planned variations in sequence parameters, such as repetition or echo times. The signal measurements are then fitted to an appropriate relaxation or other tissue-property model, producing numerical maps. Investigators can examine those maps within tissue and compare values across subjects or repeated examinations when acquisition and analysis remain consistent.
Medical users may apply qMRI to characterize tissue composition, investigate disease-related changes, and evaluate treatment response. Its measurements can supplement anatomical images when the research question concerns how tissue properties differ, not only where structures appear. The same quantitative framework also supports comparisons among patients, helping studies assess patterns across groups rather than relying solely on visual impressions.
Repeated qMRI examinations can provide numerical values for comparing tissue at different time points. This makes the approach relevant to longitudinal research, where investigators may ask whether disease-related properties change or whether tissue responds to treatment. Because the maps express measurements rather than only appearance, they can help organize objective comparisons over time while complementing clinical interpretation.