====== Magnetic resonance ====== ====== Techniques ====== Magnetic resonance techniques are non-invasive methods based on nuclear magnetic resonance (NMR) principles. They are widely used in medical diagnostics, neuroscience, and research. ===== ๐Ÿง  Magnetic Resonance Imaging (MRI) ===== **Purpose:** Non-invasive imaging of soft tissues. **Principle:** Uses magnetic fields and radiofrequency pulses to align and perturb hydrogen nuclei. see [[Magnetic resonance imaging]] ==== Common MRI Sequences ==== * **T1-weighted (T1W)** โ€“ Good for anatomy. * **T2-weighted (T2W)** โ€“ Highlights pathology (e.g. edema). * **FLAIR** โ€“ Suppresses CSF signal to detect periventricular lesions. * **DWI/ADC** โ€“ Detects diffusion restriction (e.g. acute stroke). * **SWI** โ€“ Sensitive to hemorrhage and calcification. * **fMRI** โ€“ Functional mapping based on BOLD signal. * **MRA (MR Angiography)** โ€“ Vascular imaging without catheterization. ===== ๐Ÿงฌ Magnetic Resonance Spectroscopy (MRS) ===== **Purpose:** Quantifies brain metabolites (e.g., NAA, choline, creatine). **Use:** Brain tumors, metabolic disorders, epilepsy. ===== ๐Ÿ’จ Diffusion Imaging ===== * **DWI (Diffusion-Weighted Imaging):** Highlights areas with restricted water diffusion (e.g. stroke). * **DTI (Diffusion Tensor Imaging):** Maps white matter tracts using diffusion anisotropy. ===== ๐Ÿฉธ Perfusion Imaging (PWI) ===== **Purpose:** Evaluates tissue perfusion and vascular integrity. **Methods:** * **DSC (Dynamic Susceptibility Contrast)** * **DCE (Dynamic Contrast-Enhanced)** * **ASL (Arterial Spin Labeling)** โ€“ Contrast-free perfusion method. ===== ๐Ÿงฌ Magnetic Resonance Fingerprinting (MRF) ===== **Innovative method** for simultaneous mapping of multiple tissue properties (T1, T2, etc.). **Advantages:** Faster scan, reproducible quantitative data. ===== ๐Ÿงฒ Susceptibility-Weighted Imaging (SWI) ===== **Purpose:** Highlights paramagnetic substances such as deoxyhemoglobin and iron. **Use:** Microbleeds, cavernomas, venous anatomy. ===== ๐Ÿงช Functional MRI (fMRI) ===== **Purpose:** Detects brain activation based on blood oxygenation (BOLD signal). **Applications:** Language and motor mapping, especially in presurgical planning. ---- **Tags:** {{tag>mri radiology neurology imaging techniques}}