Progress of functional magnetic resonance imaging in the assessment of transplanted kidney function

Kidney transplantation is considered the best therapeutic option for end-stage chronic kidney disease. The dynamic evaluation of transplanted kidney function and rejection monitoring after kidney transplantation is also crucial. Currently, the definitive means of evaluating transplanted kidney function is the percutaneous renal puncture tissue biopsy. However, a biopsy is invasive and has limited sampling, so it cannot dynamically detect transplanted kidney function. Magnetic resonance imaging (MRI) is a noninvasive, high-contrast, and high-resolution soft tissue imaging method. With the advent of new functional arrays such as diffusion-weighted imaging, magnetic resonance elastography, blood oxygen level-dependent imaging, and arterial spin-labeled imaging, among others, renal function can be evaluated from multiple angles such as diffusion, morphology, oxygenation, perfusion, metabolism and microstructure changes non-invasively. In this paper, we present those mentioned functional MRI techniques to better comprehend the role and value of each technique in the assessment of functional status after kidney transplantation, and to open new avenues for future related studies.