MRIModalitäten

MRIModalitäten refers to the various techniques and pulse sequences used in Magnetic Resonance Imaging (MRI) to generate images of the body. Different MRI modalities highlight different tissue properties, allowing for a comprehensive evaluation of anatomy and pathology.

One of the most fundamental modalities is T1-weighted imaging, which is excellent for visualizing anatomy and detecting fat. T2-weighted imaging, on the other hand, is sensitive to water content and is therefore crucial for identifying edema, inflammation, and tumors. FLAIR (Fluid Attenuated Inversion Recovery) is a variation of T2-weighted imaging that suppresses the signal from free fluid, making it particularly useful for detecting lesions in the brain that are close to cerebrospinal fluid.

Diffusion-weighted imaging (DWI) measures the random motion of water molecules within tissues. It is highly sensitive to subtle changes in tissue microstructure and is invaluable for the early detection of stroke, as well as for characterizing tumors and assessing tissue viability. Apparent Diffusion Coefficient (ADC) maps are derived from DWI and provide quantitative information about diffusion.

Contrast-enhanced MRI utilizes an intravenous contrast agent, typically gadolinium-based, to improve the visualization of blood vessels and abnormal tissues that have increased vascularity, such as tumors and areas of inflammation. Sequences like Gradient Echo (GRE) are often used in conjunction with contrast to highlight these areas.

Other specialized MRI modalities include MR angiography (MRA) for visualizing blood vessels, MR venography (MRV) for veins, and functional MRI (fMRI) for assessing brain activity by detecting changes in blood flow. The choice of MRI modality depends on the clinical question being asked and the specific anatomical region being examined.