Abstract：This paper briefly introduces the principles and influence factors of diffusion weighted MRI(DW MRI), and multi-b values in clinical application of DWI. The challenges exist in using traditional simple water diffusion to interpret the principle of clinical DW MR imaging were also discussed. The theory of aquaporin and its recent research status, as well as the relationship between apparent diffusion coefficient(ADC) under pathological and physiological condition and water channel protein(aquaproins, AQPs) expression were focused on. Until now, no result was acquired through using molecular imaging technique for direct access of the relationship between ADC and AQP expression. Finally, the new prospect of the water channel protein molecular imaging was introduced. From the aspect of molecular biology, molecular medicine and molecular imaging to renew knowledge and upgrade the point of view in recognizing water diffusion MR imaging and its potential clinical application is urgent and important.
2013, Vol. 24 
