In vivo magnetic resonance spectroscopy

As magnetic resonance spectroscopy (MRS ) is a system based on the magnetic resonance imaging method is known in the medicine and biochemistry, spatially resolved with the biochemical observations can be performed in a volume element. So that different chemicals (→ metabolites) can be identified and quantified in the living tissue due to their chemical shift.

Basics

Magnetic resonance spectroscopy (MRS) is derived from the NMR and commonly referred to in vivo method for the measurement of metabolite concentrations in different tissues. Most commonly it by NMR measurements on the most accessible and present in biological tissues in great abundance hydrogen (1H)- cores are performed less frequently in phosphorus ( 31P) or carbon ( 13C). ( More Basics for NMR spectroscopy there.)

With the help of 1H -MRS in a clinical magnetic resonance imaging system, N- acetylaspartate be detected as cell membrane markers as markers of neuronal or choline -containing molecules. Also lactate and citrate, as well as the CH2 and CH3 groups of lipids and other macromolecules can be detected. The 31P -MRS is mainly used for the investigation of cellular energy metabolism, while the 13C -MRS provides an insight into the cellular glucose metabolism. Clinical studies have been performed mainly in brain, skeletal muscle, heart, liver and prostate. In recent years, clinical MRS studies have increased significantly in oncology.

Technology

The MRS allows to represent biochemical properties of tissue and to detect differences of the physiological norm. So benign prostate tissue contains more citrate, choline but less than the Degenerate. In the living brain, it allows to represent the metabolism of phospholipids and high-energy phosphates.

In MRS, a certain volume that is previously positioned in overview images are measured in a tissue. This method is also referred to as single-voxel spectroscopy ( SVS ). It is also possible to measure a plurality of voxels at the same time, a larger localized volume is divided by a plurality of phase encoding in small volumes. This method is called multivoxel spectroscopy or chemical shift imaging and can be performed in two or three dimensions.

Areas of application

Prostate cancer: Combined with a magnetic resonance imaging the three-dimensional MRS point of both methods with a probability of about 90% for the presence of malignant degenerated prostate tissue in matching results. The combination of both methods can be useful both in the planning of biopsies and therapies of the prostate, as well as for monitoring the success of a therapy.

In the context of schizophrenia research, it is also used.