BACKGROUND: Despite rapid advances in cardiac computed tomography (CT), a strategy for optimal visualization of perfusion abnormalities on CT has yet to be validated.
OBJECTIVE: We evaluated the performance of several postprocessing techniques of source data sets to detect and characterize perfusion defects in acute myocardial infarctions with cardiac CT.
BACKGROUND: Perfusion defects (PDs) detected with cardiac magnetic resonance (CMR) imaging predict the functional recovery of myocardial function after acute myocardial infarction.
OBJECTIVE: We evaluated the ability of cardiac computed tomography (CCT) to predict the recovery of regional left ventricular (LV) systolic function after ST elevation myocardial infarction (STEMI).
OBJECTIVES: This study aimed to test the hypothesis that metabolic activity within periodontal tissue (a possible surrogate for periodontal inflammation) predicts inflammation in a remote atherosclerotic vessel, utilizing (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging.
BACKGROUND: Several lines of evidence establish periodontal disease as an important risk factor for atherosclerosis. FDG-PET imaging is an established method for measuring metabolic activity in human tissues and blood vessels.
BACKGROUND: Myocardial delayed enhancement (MDE) by gadolinium-enhanced cardiac MRI is well established for myocardial scar assessment in ischemic and non-ischemic heart disease. The role of MDE by cardiac CT (CT-MDE) is not yet defined.
Bexarotene (Targretin) is a retinoid X receptor (RXR) agonist that has applications for treatment of T cell lymphoma and proposed mechanisms of action in Alzheimer's disease that have been the subject of recent controversy. Carbon-11 labeled bexarotene ([(11)C-carbonyl]4-[1-(3,5,5,8,8-pentamethyltetralin-2-yl)ethenyl]benzoic acid) was synthesized using a Cu-mediated cross-coupling reaction employing an arylboronate precursor 1 and [(11)C]carbon dioxide under atmospheric pressure in 15 ± 2% uncorrected radiochemical yield (n = 3), based on [(11)C]CO2.
The ability to trigger functional magnetic resonance imaging (fMRI) acquisitions related to the occurrence of EEG-based physiologic transients has changed the field of fMRI into a more dynamically based technique. By knowing the temporal relationship between focal increases in neuronal firing rates and the provoked focal increase in blood flow, investigators are able to maximize the fMR-linked images that show where the activity originates.
Here, we combine magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) to detect the dynamic brain responses to 3D-SFM. We manipulated the coherence of randomly moving dots to create different levels of 3D perception and investigated the associated changes in brain activity. Results of the fMRI analysis were used to impose plausible constraints on the MEG inverse calculation to improve spatial resolution of the spatiotemporal activity estimates. Time-frequency analysis was also employed to elucidate spatiotemporal dynamic changes in the spontaneous brain activities.
Obtaining high quality electroencephalogram (EEG) data simultaneously with functional MRI (fMRI) recordings is increasingly relevant for the study of cognitive and clinical brain states - as EEG-fMRI offers uniquely high spatiotemporal resolution imaging of brain activity. However, the utility of this technique is limited by ballistocardiogram (BCG) artifacts induced in the EEG by cardiac pulsation and head movement inside the magnetic field. In this paper, we introduce a novel model-based harmonic regression technique to remove BCG artifacts from EEG recorded in the MR scanner.
It has been long appreciated that anesthetic drugs induce stereotyped changes in electroencephalogram (EEG), but the relationships between the EEG and underlying brain function remain poorly understood. Functional imaging methods including positron emission tomography (PET) and functional magnetic resonance imaging (fMRI), have become important tools for studying how anesthetic drugs act in the human brain to induce the state of general anesthesia. To date, no investigation has combined functional MRI with EEG to study general anesthesia.