Radio-frequency probe for 1H decoupled 31P MRS of the head and neck region.

For optimal performance of 31P MRS at 1.5 Tesla, the use of a double resonant probe is essential to enable the application of 1H decoupling and Nuclear Overhauser Enhancement. This note describes the design, evaluation and safety validation of a versatile and compact probe optimized for 1H decoupled 31P MRS studies of tumors close to the surface of the body, in particular the head and neck region.

Skin temperature increase during local exposure to high-power RF levels in humans.

The local temperature response of the skin on heating due to prolonged exposure to RF radiation by a surface coil was investigated in five healthy volunteers. Temperature changes induced by RF radiation were measured at the skin of the calf muscle by a fluoroptic probe. Exposure to superficial specific absorption rate (SAR) levels of 6.

Assessment of human muscle glycogen synthesis and total glucose content by in vivo 13C MRS.

Background: Obesity is often accompanied by a decreased ability of insulin to stimulate glucose uptake and glycogenesis in skeletal muscle. The aim of this study was to investigate the rate of glycogen formation and of muscular glucose content in relation to insulin sensitivity under euglycemic conditions.

Materials And Methods: We applied a hyperinsulinemic (430 pmol m-2 min-1) euglycemic clamp with infusion of 20% glucose (30% enriched with 13C-1-glucose) to 8 subjects with a wide range of insulin sensitivities.

Human prostate: multisection proton MR spectroscopic imaging with a single spin-echo sequence--preliminary experience.

The authors investigated the feasibility of a multisection proton magnetic resonance (MR) spectroscopic imaging technique for the acquisition of metabolic information in the human prostate. Multisection MR spectroscopic imaging was performed of a citrate phantom and of the prostates of eight adult volunteers. High-quality proton MR spectra and citrate metabolite maps of the prostate were obtained with this method.

Heteronuclear cross polarization for enhanced sensitivity of in vivo 13C MR spectroscopy on a clinical 1.5 T MR system.

The potential of heteronuclear ¿1H-13C¿ cross polarization was studied for optimization of the signal-to-noise ratio in in vivo 13C MR spectroscopy at the clinical field strength of 1.5 T. Experiments on the human calf showed a significant chemical-shift selective signal enhancement on triglyceride signals of 3.