Changes in brain response to urgency before and after treatment of urgency urinary incontinence with onabotulinumtoxin A

Abstract

Introduction: To better understand the role of the brain in urgency urinary incontinence (UUI), we used onabotulinumtoxin A (BoNTA) as a probe to evaluate changes in the brain's response to urgency in successful and unsuccessful treatment. Because BoNTA acts peripherally, brain changes observed should represent a reaction to changes in bladder function caused by BoNTA, or changes in the brain's compensatory mechanisms, rather than a direct effect of BoNTA on the brain. Methods:We recruited 20 women aged over 60 years with nonneurogenic UUI who were to undergo treatment with onabotulinum A toxin injected intravesically. We performed a baseline evaluation which included a 3-day bladder diary and functional magnetic resonance imaging with an urgency provocation task; we repeated this evaluation 6 weeks posttreatment. We performed an analysis of variance on a priori selected regions of interest and post hoc voxel-wise analysis on responders and nonresponders to treatment.Results: We found a significant interaction in the right insula [F(1,18) = 5.5, p = 0.031]; activity was different during urgency provocation in responders and non-responders to therapy, before and after therapy. The supramarginal gyrus (SMG) and inferior frontal gyrus (IFG) also displayed significant interactions (p < 0.005). Activity in the periaqueductal gray and prefrontal cortex was correlated with number of leakage episodes (p < 0.05). Conclusion:The changes seen in the brain control mechanism after therapy likely reflect reduced bladder sensation caused by BoNTA's peripheral action. We ascribe the SMG and IFG changes to a coping mechanism for urgency which is reduced in those who respond well to treatment.

Quantification of Aging-Related Decreases in Sensory Innervation of the Bladder Trigone in Rats

“…Neuroimaging studies incorporating manipulation of bladder volumes and assessment of bladder sensations with brain activity and connectivity patterns may help to further understand the impact of aging-associated changes in bladder sensory innervation. Recent neuroimaging developments in the field of neuro-urology highlight the added value of interdisciplinary approaches to improve our understanding of the central control of the lower urinary tract [ 27 - 29 ].…”