钆贝葡胺 (Multihance)

概览

Gadobenic acid is a gadolinium compound used as a contrast agent in MRIs.

作用机制

Based on the behavior of protons when placed in a strong magnetic field, which is interpreted and transformed into images by magnetic resonance (MR) instruments. Paramagnetic agents have unpaired electrons that generate a magnetic field about 700 times larger than the proton's field, thus disturbing the proton's local magnetic field. When the local magnetic field around a proton is disturbed, its relaxation process is altered. MR images are based on proton density and proton relaxation dynamics. MR instruments can record 2 different relaxation processes, the T1 (spin-lattice or longitudinal relaxation time) and the T2 (spin-spin or transverse relaxation time). In magnetic resonance imaging (MRI), visualization of normal and pathological brain tissue depends in part on variations in the radiofrequency signal intensity that occur with changes in proton density, alteration of the T1, and variation in the T2. When placed in a magnetic field, Gadobenate Dimeglumine shortens both the T1 and the T2 relaxation times in tissues where it accumulates. At clinical doses, Gadobenate Dimeglumine primarily affects the T1 relaxation time, thus producing an increase in signal intensity. Gadobenate Dimeglumine does not cross the intact blood-brain barrier; therefore, it does not accumulate in normal brain tissue or in central nervous system (CNS) lesions that have not caused an abnormal blood-brain barrier (e.g., cysts, mature post-operative scars).

适应症

Gadobenate dimeglumine is indicated for use in magnetic resonance imaging (MRI) of the central nervous system in adult and pediatric patients in order to visualize lesions with abnormal blood-brain barrier or abnormal vascularity of the brain, spine, and associated tissues. It is also indicated for use in magnetic resonance angiography (MRA) to evaluate adults with known or suspected renal or aorto-ilio-femoral occlusive vascular disease.

• Vascular Occlusion