MP52-12: Predicting Response to Transcutaneous Electrical Spinal Cord Neuromodulation Based on Pre-Treatment Micturition-Associated Brain Activity in Stroke Survivors.
Introduction: Stroke patients often develop lower urinary tract symptoms (LUTS) due to disruption in the brain centers that control micturition. Transcutaneous spinal cord stimulation (TSCS) is a novel neuromodulation approach that has been previously shown to improve LUT function in these patients. However, the characteristics of responders to TSCS have not been previously identified. In this study, we assessed micturition-related brain activity as a biomarker of responsiveness to TSCS therapy for LUT dysfunction secondary to stroke. Methods: Twelve patients with stroke-related LUTS were enrolled to receive 12 weeks (24 sessions) of TSCS in a prospective cohort study. Patients underwent simultaneous blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) and urodynamics during their baseline evaluation. LUTS were assessed using the International Consultation on Incontinence Overactive Bladder(ICIQ-OAB) questionnaire before and after completing TSCS. Responders were defined as those who reported >= 60% reduction in the ICIQ-OAB score. BOLD signal during maximal urgency (defined as 10 seconds preceding a detrusor contraction) was compared between responders and non-responders using statistical parametric mapping (p < 0.01, cluster size > 25 voxels). Models were controlled for age, sex, and time since stroke. Results: Of 12 patients enrolled in the study, six were defined as responders to therapy, reporting a mean decrease in ICIQ-OAB by 8.6±0.91 points (p < 0.01). Responders exhibited significantly higher BOLD signals in 16 clusters, including left insula, left middle cingulate cortex, bilateral cuneus, left precuneus, left precentral gyrus, left inferior frontal gyrus, and right temporal gyrus. Nonresponders exhibited significantly higher BOLD signals in 7 clusters centered in the corpus callosum and the basal ganglia. Conclusions: TSCS is a promising novel neuromodulation modality for the mitigation of neurogenic LUTS (NLUTS). Here we demonstrate that micturition-related brain activity may be a useful biomarker for predicting response to TSCS in patients with NLUTS secondary to stroke. Responders demonstrated higher BOLD signals in several cortical areas than non-responders, suggesting that a baseline level of brain activity may be necessary in order to have a successful outcome with TSCS. SOURCE OF Funding: Urology Care Foundation
