The multiple slice SL imaging technique was introduced in 1993. MT based tissue contrast may even more effectively be generated with the spin lock (SL) technique which probes tissue relaxation processes at very low magnetic field strengths while maintaining the high signal-to-noise ratio provided by the polarizing magnetic system In a SL experiment, a preparation or locking pulse is applied before the signal collecting conventional imaging sequence. The signal of tissues with a high macromolecular content is reduced on MT images in comparison to the standard images. The method is based on saturating macromolecular spins with a dedicated irradiation radiofrequency (RF) -pulse, and observing the effects of the subsequent exchange processes.

The magnetization transfer (MT) technique in MRI was introduced in 1989 (Wolff and Balaban, 1989). Therefore, the determination of liver lesion count, and the nature of the lesion are important.ДЄt present, the most accurate noninvasive method for the assessment of liver lesion count is magnetic resonance imaging (MRI).

Modern operative techniques and local therapies such as radiofrequency (RF) ablation are effective methods to treat liver metastases or primary hepatic malignancies. 3 PRINCIPIILE FIZICE IN REZONANTA MAGNETICA NUCLEARAДЈ.2 MAGNETIZAREA LONGITUDINALA SI TRANSVERSALAД¤.1 AGENTI DE CONTRAST PARAMAGNETICICU DISTRIBUTIE INTROVASCULARA EXTRACELULARД¤.4 AGENTI DE CONTRAST AI FLUIDELOR EXTRACELULAREД¤.6 AGENTII DE CONTRAST GASTROINTESTINALIДҐ ARTEFACTELE IN REZONANTA MAGNETICA NUCLEARAДҐ.1 ARTEFACTELE CAMPULUI DE RADIOFRECVENTAДҐ.3 ARTEFACTELE IN DIRECTIA DE CODARE A FRECVENTEIДҐ.4 ARTEFACTELE IN DIRECTIILE DE CODARE A FAZEI SI FRECVENTEIДҐ.5 ARTEFACTELE INDEPENDENTE DE DIRECTIA DE CODAREД¦.1.5 SECVENTELE FSE-IR, FLAIR (FLUID ATTENUATED INVERSION RECOVERY) SI STIR (SHORT TI INVERSION RECOVERY)Д¦.1.6 SECVENTELE DE PULS GRE (COHERENT GRADIENT ECHO) SI SPGR(SPOILED GRADIENT ECHO)Д¦.1.8 SECVENTELE DWI (DIFFUSION WEIGHTED IMAGING)Д¦.1.9 SECVENTELE MRA (MAGNETIC RESONANCE ANGIOGRAPHY)Д¦.1.9.1 IMAGINI DINAMICE (DYNAMIC IMAGING)Д¦.1.9.2 IMAGINI FUNCTIONALE ( FUNCTIONAL IMAGING - FMRI )Д¦.2 PUNEREA IN PRACTICA A SECVENTELOR DE PULS

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