Kreydin Evgeniy I, Abedi Aidin, Morales Luis, Montero Stefania, Kohli Priya, Ha Nhi, Chapman David, Abedi Armita, Ginsberg David, Jann Kay, Harvey Richard L, Liu Charles Y
Department of Urology (E.I.K., L.M., S.M., D.C., D.G., C.Y.L.), Keck School of Medicine of the University of Southern California, Los Angeles.
USC Neurorestoration Center (E.I.K., Aidin Abedi, C.Y.L.), University of Southern California, Los Angeles.
Stroke. 2025 Jun;56(6):1516-1527. doi: 10.1161/STROKEAHA.124.048057. Epub 2025 Apr 10.
Urinary incontinence after a stroke significantly affects patient outcomes and quality of life. It is commonly associated with uninhibited detrusor contractions, but the underlying neural mechanisms remain poorly understood. This study aimed to explore the brain activity patterns associated with volitional and involuntary bladder contractions in stroke survivors.
This cohort study enrolled 15 stroke survivors with documented urinary incontinence and 9 healthy controls. Participants underwent simultaneous blood oxygen level-dependent functional magnetic resonance imaging of the brain and urodynamics, capturing 25 involuntary and 23 volitional bladder emptying events in patients with stroke and 35 volitional voiding events in healthy individuals. We used general linear modeling in functional magnetic resonance imaging analysis to discern neural activity patterns during these events and in the phases leading up to them, aiming to identify neural mechanisms underlying involuntary versus volitional urinary control. Statistical significance for neuroimaging analyses was set at <0.005 with a minimum cluster size of 25 voxels.
During volitional emptying events, both healthy controls and stroke survivors exhibited increases in activation in regions implicated in sensorimotor control and executive decision-making, such as the brainstem, cingulate cortex, prefrontal cortex, and motor areas. In contrast, involuntary emptying events were associated with minimal changes in brain activity, suggesting minimal cortical involvement. Bladder filling preceding volitional contractions was associated with activity in the salience network (insula, anterior cingulate gyrus) in stroke survivors and healthy controls. Conversely, although there was an increase in overall blood oxygen level-dependent signal, activation of the salience network was conspicuously absent during bladder filling preceding involuntary contractions.
The findings suggest that the salience network plays an important role in maintaining urinary continence in stroke survivors. The inability to activate the salience network may underpin the pathophysiology of poststroke urinary incontinence. Interventions aimed at modulating this network could potentially ameliorate lower urinary tract symptoms in this patient population.
URL: https://www.clinicaltrials.gov; Unique identifier: NCT05301335.
中风后尿失禁显著影响患者的预后和生活质量。它通常与逼尿肌无抑制性收缩有关，但其潜在的神经机制仍知之甚少。本研究旨在探讨中风幸存者中与自主性和非自主性膀胱收缩相关的脑活动模式。
本队列研究纳入了15名有尿失禁记录的中风幸存者和9名健康对照者。参与者同时接受了基于血氧水平依赖性功能磁共振成像的脑部检查和尿动力学检查，记录了中风患者的25次非自主性和23次自主性膀胱排空事件，以及健康个体的35次自主性排尿事件。我们在功能磁共振成像分析中使用一般线性模型来识别这些事件及其前期阶段的神经活动模式，旨在确定非自主性与自主性排尿控制的潜在神经机制。神经影像学分析的统计学显著性设定为<0.005，最小聚类大小为25体素。
在自主性排空事件期间，健康对照者和中风幸存者在涉及感觉运动控制和执行决策的区域，如脑干、扣带回皮质、前额叶皮质和运动区，激活均增加。相比之下，非自主性排空事件与脑活动的最小变化相关，表明皮质参与最少。中风幸存者和健康对照者在自主性收缩前的膀胱充盈与突显网络（脑岛、前扣带回）的活动有关。相反，尽管整体血氧水平依赖信号增加，但在非自主性收缩前的膀胱充盈期间，突显网络的激活明显缺失。
研究结果表明，突显网络在维持中风幸存者的尿失禁中起重要作用。无法激活突显网络可能是中风后尿失禁病理生理学的基础。旨在调节该网络的干预措施可能会改善该患者群体的下尿路症状。
