Objective
To evaluate the visualization of gallbladder stones on susceptibility-weighted imaging (SWI).
Materials and Methods
Imaging data from 47 patients who underwent clinically indicated cholecystectomy was reviewed. Breath-hold SWI was added to the magnetic resonance imaging protocol and magnitude and phase data was reviewed for gall-stones visualization. Phase signature, that is, diamagnetic, paramagnetic, or mixed, was also noted in the stones. Magnetic susceptibility value of surgically extracted gallstones were imaged ex vivo (n = 37).
Results
In 45 of 47 cases, gallstones were surgically confirmed. In 43 cases, gallstones were visualized in the SWI. In 1 case, although routine imaging failed, stones were visualized on SWI. In 29 diamagnetic, 7 paramagnetic and 9 cases mixed phase were seen. In an ex vivo study, magnetic susceptibility of stones was found ranging between −0.102 and −0.916 ppm for diamagnetic and 0.203 and 486 ppm for paramagnetic stones.
Conclusions
Gallbladder stones can be visualized with SWI and may be added to the routine magnetic resonance imaging protocol for its evaluation.