Cavusoglu, M., Pfeuffer, J., Ugurbil, K., Uludag, K.
Arterial spin labeling (ASL) using magnetic resonance imaging (MRI) is a powerful noninvasive technique to investigate the physiological status of brain tissue by measuring cerebral blood flow (CBF)....
Mishra, R., Su, W., Pohmann, R., Pfeuffer, J., Sauer, M.G., Ugurbil, K., ...
Molecular imaging of cells and cellular processes can be achieved by tagging intracellular targets such as receptors, enzymes, or mRNA. Seeking to visualize the presence of specific mRNAs by magnetic...
The effect of labeling parameters on perfusion-based fMRI in nonhuman primates (2008)
Zappe, A.-C., Pfeuffer, J., Merkle, H., Logothetis, N.K., Goense, J.B.M.
Juchem, C., Logothetis, N.K., Pfeuffer, J.
A pronounced characteristic of the microcircuits of the primary visual cortex (striate cortex or area V1) in primates is the strong recurrent excitation and the tight balance between excitation and...
Su, W., Mishra, R., Pfeuffer, J., Wiesmüller, K.H., Ugurbil, K., Engelmann, J.
In order to image mRNA transcription by in vivo magnetic resonance imaging (MRI), two intracellular MR contrast agents were developed, which are composed of a Gd-DOTA complex, a peptide nucleic acid...
Zappe, A.-C., Reichold, J., Burger, C., Weber, B., Buck, A., Pfeuffer, J., ...
Noninvasive absolute quantification of cerebral blood flow (CBF) with high spatial resolution is still a challenging task. Arterial spin labeling (ASL) is a promising magnetic resonance imaging (MRI)...
Keliris, G.A., Shmuel, A., Ku, S.-P., Pfeuffer, J., Oeltermann, A., Thomas, S., ...
Zappe, A., Merkle, H., Pfeuffer, J., Logothetis, N.K.
Perfusion-based imaging in the monkey primary visual cortex was performed at 7 T applying continuous arterial spin labeling (CASL). Increased perfusion sensitivity and SNR at high magnetic field (due...
Combined Passive and Active Shimming for In Vivo MR Spectroscopy at High Magnetic Field (2006)
Juchem, C., Mueller-Bierl, B., Schick, F., Logothetis, N.K., Pfeuffer, J.
Zappe, A.C., Merkle, H., Logothetis, N.K., Pfeuffer, J.
CASL experiments in the monkey brain were performed at 4.7 T and 7 T using a separate labeling coil. Increased sensitivity and SNR were achieved by a custom-made three-coil setup and high magnetic...
Juchem, C., Schick, F., Logothetis, N.K., Pfeuffer, J.
High magnetic fields increase the sensitivity and spectral dispersion in magnetic resonance spectroscopy (MRS). In contrast, spectral peaks are broadened in vivo at higher field strength due to...
Pfeuffer, J., Merkle, H., Logothetis, N.K.
The first high-resolution CBF maps in the Macaca mulatta are shown that were obtained with 500 m in-plane resolution (single-shot GE-FAIR). High sensitivity was achieved by using a 7 T system...
Design, synthesis and characterization of new smart MR contrast agents sensitive to pH (2005)
Mishra, A.K., Pfeuffer, J., Mishra, A., Logothetis, N.K.
New gadolinium-based MR contrast agents Gd-DO3A-EP (-phosphono-ethyl) and Gd-DO3A-EPE (diethyl-phosphano-ethyl) were designed and synthesized to trace physiological changes of pH and calcium...
Mishra, A., Pfeuffer, J., Mishra, R., Logothetis, N.K., Mishra, A.K.
Smart MR contrast agents are chelated paramagnetic molecules, whose relaxivity changes as a function of their chemical environment (e.g. changes in pH, calcium or neurotransmitter concentration). The...
Localized 1H MR spectroscopy in the alert monkey at 7 Tesla (2005)
Pfeuffer, J., Juchem, C., Merkle, H., Logothetis, N.K.
Localized 1H MRS in alert monkeys was performed in a vertical 7T/60cm MR system utilizing increased sensitivity and spectral dispersion gained at high field. Refinements of acquisition and correction...
High-resolution 1H chemical shift imaging in the monkey visual cortex (2005)
Juchem, C., Logothetis, N.K., Pfeuffer, J.
Functionally distinct anatomic subdivisions of the brain can often be only a few millimeters in one or more dimensions. The study of metabolic differences in such structures by means of localized in...
Zappe,A.C., Merkle,H., Logothetis,N.K., Pfeuffer,J.
Arterial spin labeling is commonly used to measure cerebral blood flow (CBF) in the brain. Since CBF signal is intrinsically low, optimization of the signal-to-noise ratio (SNR) is critical. CASL...
Pfeuffer,J., Merkle,H., Logothetis,N.K.
Obtaining functional CBF maps with high spatial resolution is challenging, because the CBF signal is intrinsically low and the signal-to-noise is critical. Here we report the first high-resolution...
Localized 1H spectroscopy in the primary visual cortex V1 (2004)
Juchem,C., Merkle,H., Logothetis,N.K., Pfeuffer,J.
The primary visual cortex V1 is the elementary target, when visual function and cortical reorganization are investigated. The study demonstrates that online analysis of field distributions is helpful...
In vivo CSI of glutamate in the monkey brain (2004)
Juchem,C., Merkle,H., Logothetis,N.K., Pfeuffer,J.
CSI studies of metabolites in the human brain typically suffer from poor spatial resolution or they are restricted to substances with strong peaks that are visible at longer echo times. In this...
Pfeuffer,J., Steudel,T., Merkle,H., Logothetis,N.K.
Functional MR imaging in monkeys promises to build a bridge between brain research in humans and the large body of systems neuroscience work in animals. Simultaneous fMRI and electrophysiology was...
High-field localized 1H NMR spectroscopy in the anaesthetized and in the awake monkey (2004)
Pfeuffer,J., Juchem,C., Merkle,H., Nauerth,A., Logothetis,N.
On the Nature of the BOLD fMRI Contrast Mechanism (2004)
First developed about fifteen years ago, functional magnetic resonance imaging (fMRI) has become the leading research tool for mapping brain activity. The technique works by detecting the levels of...
Juchem,C., Merkle,H., Schick,F., Logothetis,N., Pfeuffer,J.
High magnetic fields increase the sensitivity and spectral dispersion in magnetic resonance spectroscopy (MRS). In contrast, spectral peaks are broadenedin vivo at higher field strength due to...
Zappe, A.C., Merkle, H., Logothetis, N.K., Pfeuffer, J.
Arterial spin labeling is commonly used to measure cerebral blood flow (CBF) in the brain. Since CBF signal is intrinsically low, optimization of the signal-to-noise ratio (SNR) is critical. CASL...
Pfeuffer, J., Merkle, H., Logothetis, N.K.
Obtaining functional CBF maps with high spatial resolution is challenging, because the CBF signal is intrinsically low and the signal-to-noise is critical. Here we report the first high-resolution...
Localized 1H spectroscopy in the primary visual cortex V1 (2004)
Juchem, C., Merkle, H., Logothetis, N.K., Pfeuffer, J.
The primary visual cortex V1 is the elementary target, when visual function and cortical reorganization are investigated. The study demonstrates that online analysis of field distributions is helpful...
In vivo CSI of glutamate in the monkey brain (2004)
Juchem, C., Merkle, H., Logothetis, N.K., Pfeuffer, J.
CSI studies of metabolites in the human brain typically suffer from poor spatial resolution or they are restricted to substances with strong peaks that are visible at longer echo times. In this...
Pfeuffer, J., Steudel, T., Merkle, H., Logothetis, N.K.
Functional MR imaging in monkeys promises to build a bridge between brain research in humans and the large body of systems neuroscience work in animals. Simultaneous fMRI and electrophysiology was...
High-field localized 1H NMR spectroscopy in the anaesthetized and in the awake monkey (2004)
Pfeuffer, J., Juchem, C., Merkle, H., Nauerth, A., Logothetis, N.
On the Nature of the BOLD fMRI Contrast Mechanism (2004)
First developed about fifteen years ago, functional magnetic resonance imaging (fMRI) has become the leading research tool for mapping brain activity. The technique works by detecting the levels of...
Juchem, C., Merkle, H., Schick, F., Logothetis, N., Pfeuffer, J.
High magnetic fields increase the sensitivity and spectral dispersion in magnetic resonance spectroscopy (MRS). In contrast, spectral peaks are broadenedin vivo at higher field strength due to...
Functional MR imaging of the awake monkey in a novel vertical large-bore 7 Tesla setup (2003)
Pfeuffer,J., Pauls,J., Augath,M.A., Steudel,T., Merkle,H., Logothetis,N.K.
First fMRI results in the awake trained monkey (Macaca mulatta) using a novel vertical 7T/60cm MR system are reported. The setup was custom-designed for MR imaging of monkeys in upright position and...
Proton MR Spectroscopy at 7 Tesla in the Macaque monkey (2003)
Pfeuffer,J., Juchem,C., Merkle,H., Logothetis,N.K.
First MR spectroscopy results in the anaesthetized and the awake trained monkey (Macaca mulatta) are reported using a novel vertical bore 7T/60cm MR system. The setup was custom-designed for MR...
In vivo CSI of glutamate in Macaca mulatta brain (2003)
Juchem,C., Merkle,H., Logothetis,N.K., Pfeuffer,J.
Glutamate is the main excitatory neurotransmitter in the CNS and plays together with glutamine an important role in brain physiology. A quantitative spatially resolved analysis of glutamate separate...
Spatial Dependence of the Nonlinear BOLD response at Short Stimulus Duration (2003)
Pfeuffer,J., McCullough,J.C., De Moortele,P.-F., Ugurbil,K., Hu,X.
Functional MR imaging of the awake monkey in a novel vertical large-bore 7 Tesla setup (2003)
Pfeuffer, J., Pauls, J., Augath, M.A., Steudel, T., Merkle, H., Logothetis, N.K.
First fMRI results in the awake trained monkey (Macaca mulatta) using a novel vertical 7T/60cm MR system are reported. The setup was custom-designed for MR imaging of monkeys in upright position and...
Proton MR Spectroscopy at 7 Tesla in the Macaque monkey (2003)
Pfeuffer, J., Juchem, C., Merkle, H., Logothetis, N.K.
First MR spectroscopy results in the anaesthetized and the awake trained monkey (Macaca mulatta) are reported using a novel vertical bore 7T/60cm MR system. The setup was custom-designed for MR...
In vivo CSI of glutamate in Macaca mulatta brain (2003)
Juchem, C., Merkle, H., Logothetis, N.K., Pfeuffer, J.
Glutamate is the main excitatory neurotransmitter in the CNS and plays together with glutamine an important role in brain physiology. A quantitative spatially resolved analysis of glutamate separate...
Spatial Dependence of the Nonlinear BOLD response at Short Stimulus Duration (2003)
Pfeuffer, J., McCullough, J.C., De Moortele, P.-F., Ugurbil, K., Hu, X.
Pfeuffer,J., De Moortele,P.-F., Ugurbil,K., Hu,X., Glover,G.H.
To decrease noise from respiration induced phase and frequency fluctuations, a simple correction of the "Dynamic Off-Resonance in K-space" (DORK) was developed. The correction uses phase information...
Spatial Dependence of the Nonlinear BOLD Response at Short Stimulus Duration (2002)
Pfeuffer,J., McCullough,J.C., Van De Moortele,P.-F., Ugurbil,K., Hu,X.
Non-linearities in the measured BOLD data were found for the response integral and width. With the high sensitivity at 7T, a voxel-based analysis was feasible and was used to investigate the spatial...
Perfusion-based High-Resolution Functional Imaging in the Human Brain at 7 Tesla (2002)
Pfeuffer,J., Adriany,G., Shmuel,A., Yacoub,E., De Moortele,P.-F., Hu,X., ...
In this paper, CBF-based functional imaging is reported at sub-millimeter resolution (0.9 mm) in humans for the first time. High sensitivity was made possible by signal-to-noise gains at the high...
Pfeuffer,J., De Moortele,P.-F., Ugurbil,K., Hu,X., Glover,G.H.
In functional magnetic resonance imaging, a rapid method such as echo-planar (EPI) or spiral is used to collect a dynamic series of images. These techniques are sensitive to changes in resonance...
Pfeuffer,J., De Moortele,P.-F., Yacoub,E., Shmuel,A., Adriany,G., Andersen,P., ...
Functional neuroimaging in the human brain using non-invasive magnetic resonance methods has the potential of providing highly resolved maps of neuronal activation. Decreasing the voxel size and...
Perfusion-based High-Resolution Functional Imaging in the Human Brain at 7 Tesla (2002)
Pfeuffer,J., Adriany,G., Shmuel,A., Yacoub,E., De Moortele,P.-F., Hu,X., ...
Perfusion-based magnetic resonance imaging measures cerebral blood flow (CBF) at the capillary level and can be used for functional studies based on the tight spatial coupling between brain activity...
Pfeuffer, J., De Moortele, P.-F., Ugurbil, K., Hu, X., Glover, G.H.
To decrease noise from respiration induced phase and frequency fluctuations, a simple correction of the "Dynamic Off-Resonance in K-space" (DORK) was developed. The correction uses phase information...
Spatial Dependence of the Nonlinear BOLD Response at Short Stimulus Duration (2002)
Pfeuffer, J., McCullough, J.C., Van De Moortele, P.-F., Ugurbil, K., Hu, X.
Non-linearities in the measured BOLD data were found for the response integral and width. With the high sensitivity at 7T, a voxel-based analysis was feasible and was used to investigate the spatial...
Perfusion-based High-Resolution Functional Imaging in the Human Brain at 7 Tesla (2002)
Pfeuffer, J., Adriany, G., Shmuel, A., Yacoub, E., De Moortele, P.-F., Hu, X., ...
In this paper, CBF-based functional imaging is reported at sub-millimeter resolution (0.9 mm) in humans for the first time. High sensitivity was made possible by signal-to-noise gains at the high...
MR Spectroscopy at large diffusion weighting can specifically look at intracellular components of tissue that are characterized by restricted diffusion and a small apparent diffusion coefficient....
Pfeuffer, J., De Moortele, P.-F., Ugurbil, K., Hu, X., Glover, G.H.
In functional magnetic resonance imaging, a rapid method such as echo-planar (EPI) or spiral is used to collect a dynamic series of images. These techniques are sensitive to changes in resonance...
Pfeuffer, J., De Moortele, P.-F., Yacoub, E., Shmuel, A., Adriany, G., Andersen, P., ...
Functional neuroimaging in the human brain using non-invasive magnetic resonance methods has the potential of providing highly resolved maps of neuronal activation. Decreasing the voxel size and...
Perfusion-based High-Resolution Functional Imaging in the Human Brain at 7 Tesla (2002)
Pfeuffer, J., Adriany, G., Shmuel, A., Yacoub, E., De Moortele, P.-F., Hu, X., ...
Perfusion-based magnetic resonance imaging measures cerebral blood flow (CBF) at the capillary level and can be used for functional studies based on the tight spatial coupling between brain activity...
Water diffusion in rat brain in vivo as detected at very large b values is multicompartmental (1999)
Pfeuffer, J., Provencher, S. W., Gruetter, R.
The diffusion-weighted signal attenuation of water in rat brain was measured with pulsed-field gradient nuclear magnetic resonance methods in a single voxel under in vivo and global ischemic...
Pfeuffer, J., Tkac, I., Provencher, S. W., Gruetter, R.
Localized in vivo H-1 NMR spectroscopy was performed with 2-ms echo time in the rat brain at 9.4 T, Frequency domain analysis with LCModel showed that the in vivo spectra can be explained by 18...