Abstract：Objective: To study the mechanism and method of molecular imaging of aquaporin by DWI-MRI with multi-b-values. Materials and Methods: On 3T MRI, multi-b-value(0~4 500 s/mm2) DWI was performed for water, contrast agent, whole blood, plasma and red blood cells using acetazolamide as an inhibitor of water channel protein on red cell membrane. Effects of the inhibitor on red blood cell morphology and signal variation of different tissues in multi-b-value imaging were observed. Results: Acetazolamide increased the diameter of red blood cell by more than 10%. B value in the range of 0~200 s/mm2 could distinguish different tissues. B value in the range of 300~1 500 s/mm2 couldn’t distinguish different tissues. When b value was greater than 1 700 s/mm2, it showed the information of water channel protein on red cell membrane. Conclusion: In DWI-MRI with multiple b values, low b value imaging has tissue specificity, but high b value can achieve aquaporin molecular imaging.
2014, Vol. 25 
