Increased BOLD sensitivity in the orbitofrontal cortex using slice-dependent echo times at 3 T.

Functional magnetic resonance imaging (fMRI) exploits the blood oxygenation level dependent (BOLD) effect to detect neuronal activation related to various experimental paradigms. Some of these, such as reversal learning, involve the orbitofrontal cortex and its interaction with other brain regions like the amygdala, striatum or dorsolateral prefrontal cortex. These paradigms are commonly investigated with event-related methods and gradient echo-planar imaging (EPI) with short echo time of 27 ms.

Imaging of lamination patterns of the adult human olfactory bulb and tract: in vitro comparison of standard- and high-resolution 3T MRI, and MR microscopy at 9.4 T.

Purpose: Neurological and smelling disorders (e.g. Alzheimer's disease, sinonasal disease) negatively affect the microstructural integrity of the olfactory bulb's (OB) cortical layers.

Chemical shift sodium imaging in a mouse model of thromboembolic stroke at 9.4 T.

Purpose: To estimate changes in the (23)Na density and in the (23)Na relaxation time T(2) * in the anatomically small murine brain after stroke.

Materials And Methods: Three-dimensional acquisition weighted chemical shift imaging at a resolution of 0.6 × 0.

Two-dimensional radial acquisition technique with density adaption in sodium MRI.

Conventional 2D radial projections suffer from losses in signal-to-noise ratio efficiency because of the nonuniform k-space sampling. In this study, a 2D projection reconstruction method with variable gradient amplitudes is presented to cover the k-space uniformly. The gradient is designed to keep the average sampling density constant.

Comparison of selective arterial spin labeling using 1D and 2D tagging RF pulses.

Generic arterial spin labeling (ASL) techniques label all brain feeding arteries. In this work, we used two different selective ASL (SASL) methods to show the perfusion of one single artery. A slice selective inversion of an area including the desired vessel was compared to a multidimensional RF pulse with Gaussian profile to label only the artery of interest.

Artifact free T2*-weighted imaging at high spatial resolution using segmented EPI sequences.

The aim of this work was the development of novel measurement techniques that acquire high resolution T2*-weighted datasets in measurement times as short as possible without suffering from noticeable blurring and ghosting artifacts. Therefore, two new measurement techniques were developed that acquire a smoother k-space than generic multi shot echo planar imaging sequences. One is based on the principle of echo train shifting, the other on the reversed gradient method.