Quantitative Changes in Cerebral Perfusion during Urinary Urgency in Women with Overactive Bladder

PURPOSE To quantitatively measure changes in cerebral perfusion in select regions of interest in the brain during urinary urgency in women with overactive bladder (OAB) using arterial spin labeling (ASL). METHODS Twelve women with OAB and 10 controls underwent bladder filling and rated urinary urgency (scale 0-10). ASL fMRI scans were performed (1) in the low urgency state after voiding and (2) high urgency state after drinking oral fluids. Absolute regional cerebral blood flow (rCBF) in select regions of interest was compared between the low and high urgency states. RESULTS There were no significant differences in rCBF between the low and high urgency states in the control group. In the OAB group, rCBF (mean ± SE, ml/100 g/min) increased by 10-14% from the low to the high urgency state in the right anterior cingulate cortex (ACC) (44.56 ± 0.59 versus 49.52 ± 1.49, p < 0.05), left ACC (49.29 ± 0.85 versus 54.02 ± 1.46, p < 0.05), and left insula (50.46 ± 1.72 versus 54.99 ± 1.09, p < 0.05). Whole-brain analysis identified additional areas of activation in the right insula, right dorsolateral prefrontal cortex, and pons/midbrain area. CONCLUSIONS Urinary urgency is associated with quantitative increase in cerebral perfusion in regions of the brain associated with processing emotional response to discomfort.