Abstract
Magnetic resonance angiography (MRA) is pivotal for diagnosing panvascular diseases. However, single-modality MRA falls short in diagnosing diverse vascular abnormalities. Thus, contrast agents combining T(1) and T(2) effects are sought for multiparameter MRA with clinical promise, yet achieving a balance in T(1) and T(2) contrast enhancement effects remains a scientific challenge. Herein, we developed a hypersensitive multiparameter MRA strategy using dual-modality NaGdF(4) nanoparticles. Because of the longer tumbling time (τ(R)), NaGdF(4) nanoparticles can improve the longitudinal relaxivity (r(1)), brightening vessels in T(1)-weighted sequences. Simultaneously, the regular arrangement of Gd(3+) in the crystal induces magnetic anisotropy, creating local static magnetic field heterogeneity and generating negative signals in T(2)-weighted sequences. Consequently, the efficacy of NaGdF(4)-enhanced high-resolution multiparameter MRA has been validated in diagnosing ischemic stroke and Alzheimer's disease in rodent models. In addition, the dual-contrast imaging has been realized on swine with a clinical 3.0-T magnetic resonance imaging scanner, highly emphasizing the clinical translation prospect.