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Short echo 1H in-vivo brain MR spectra are difficult to quantify for several reasons: low signal to noise ratio, the severe overlap of spectral lines, the presence of macromolecule resonances beneath the resonances of interest, and the effect of resonances adjacent to the spectral region of interest (SRI). This paper outlines several different(More)
OBJECTIVE It is likely that the corpus striatum is involved in obsessive-compulsive disorder (OCD). Prior studies have inconsistently found alterations in caudate volumes in patients with OCD. This study was undertaken in the hope that N-acetylaspartate and volumetric measures together would elucidate the presence and nature of corpus striatum volumetric(More)
Precise quantification of human in vivo short echo time (1)H spectra remains problematic at clinical field strengths due to broad peak linewidths and low signal-to-noise ratio (SNR). In this study, multiple STEAM spectra (TE = 20 ms, volume = 8 cm(3)) were acquired in a single individual at 1.5 T and 4 T to compare quantification precision. Test-retest(More)
OBJECTIVE This in vivo (1)H magnetic resonance spectroscopy study examined levels of glutamate, glutamine, and N-acetylaspartate in patients experiencing their first episode of schizophrenia. METHOD Localized in vivo (1)H spectra were acquired at 4.0 T from the left anterior cingulate and thalamus of 21 never-treated patients with schizophrenia and 21(More)
BACKGROUND Volumetric studies have reported reductions in the size of the corpus callosum (CC) in autism, but the callosal regions contributing to this deficit have differed among studies. In this study, a computational method was used to detect and map the spatial pattern of CC abnormalities in male patients with autism. METHODS Twenty-four boys with(More)
In order to clarify the relationship between coronary artery disease (including myocardial infarction) and image contrast in gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA)-enhanced MRI it was decided to model the myocardial tissue distribution and clearance of Gd-DTPA using the modified Kety equation. Using a canine model, myocardial tissue Gd-DTPA(More)
A technique for the simultaneous measurement of three vascular parameters: blood flow (Frho), blood volume (v(b)), and the capillary permeability-surface area product (PSrho) in breast tumors using dynamic contrast-enhanced magnetic resonance imaging (MRI) is presented. Features of the technique include measurement of precontrast tumor T(1), rapid temporal(More)
OBJECTIVE To use functional magnetic resonance imaging (fMRI) to investigate functional connectivity, and hence, underlying neural networks, in never-treated, first-episode patients with schizophrenia using a word fluency paradigm known to activate prefrontal, anterior cingulate, and thalamic regions. Abnormal connectivity between the prefrontal cortex(More)
BACKGROUND Although brain imaging studies have reported neurobiological abnormalities in autism, the nature and distribution of the underlying neurochemical irregularities are unknown. The purpose of this study was to examine cerebral gray and white matter cellular neurochemistry in autism with proton magnetic resonance spectroscopic imaging (MRSI). (More)
Lineshape distortion due to residual eddy currents and magnetic field inhomogeneities are often present in short echo time (1)H spectroscopic data. Lineshape correction methods such as QUALITY deconvolution and eddy current correction (ECC), which use a separate reference spectrum for lineshape correction, have shortcomings when unsuppressed water is chosen(More)