SU-G-IeP1-10: Permeability Evaluation of Interstitial Cystitis by DCE-MRI of the Bladder.
PURPOSE
Interstitial cystitis (IC) is a chronic and painful condition that can lead to bladder pain syndrome (BPS) in women. IC and BPS have been known to manifest after physiological changes after giving birth. In this project, we pioneered and advanced a new clinical utility using DCE-MRI to assess bladder permeability. At first IC/BPS perfusion methods were with ratio signal evaluation, we now incorporate pharmacokinetics techniques to allow for further assessment.


METHODS
In this pilot study, female patients and volunteers (IC=4, Control=3) underwent imaging with a clinical GE 3T 750W MRI system. This project was approved by the OUHSC IRB. Multiple TR Images series were acquired. Images were analyzed in the coronal plane at 0-, 3-, 6-, 9-, 12-, 15-, 20-, 25-, and 30-minute intervals. We used a three-compartmental pharmacokinetic model with these data. The compartments included: a) bladder interior site of injection, b) bladder wall, and c) external psoas muscle. The signal was transformed and corrected for T1-relaxation based on a multi-TR exponential regression before pharmacokinetic analysis.


RESULTS
Significant differences (p<0.05) were detected with relative means for T1 concentration changes (IC/BPS=0.0107, control=0.616) on the outflow between the k13 transfer coefficient, which represents the injection leakage to the external parenchyma. Trend differences (p<0.1) were found in permeability between the bladder injection site to the rim. We also found changes in the kurtosis of the histograms of regional perfusion. No detectable changes were found in the reverse directions for the above compartments (k21, k31).


CONCLUSION
We report clinical changes in this pilot study. This study illustrates early detectable evidence for a possible DCE-MRI tool that can detect permeability differences with pharmacokinetics measurement of k13. These techniques are intended to advance quantitative imaging methods for IC/BPS, per the goals/objectives of the Quantitative Imaging Biomarker Alliance (QIBA) and other AAPM and RSNA initiatives.