Imaging Biomarkers Aim to Personalize Treatment for Post-Stroke Bladder Dysfunction

These symptoms undermine independence, burden caregivers, and complicate rehabilitation and discharge planning. Clinicians often treat the bladder without targeting the brain circuits disrupted by stroke, limiting effectiveness and causing side effects. To help address this challenge, researchers have launched a brain imaging-guided study to personalize noninvasive neuromodulation for bladder control.

At the Keck School of Medicine of USC’s Mark and Mary Stevens Neuroimaging and Informatics Institute (Stevens INI), working with Rancho Los Amigos National Rehabilitation Center, investigators will map the brain networks that control continence and test whether imaging can predict who benefits from transcutaneous spinal cord stimulation (TSCS). Bladder symptoms persist in more than 30% of stroke survivors, and current medications or intravesical injections primarily address symptoms and may cause side effects. The program seeks imaging biomarkers to guide patient selection and more targeted care.

Participants, including stroke survivors with injuries in the basal ganglia, pons, or occipital lobe and healthy controls, will undergo functional magnetic resonance imaging (fMRI) while the bladder is gradually filled and monitored. fMRI will be used to observe activity and connectivity at rest and during filling and urination in regions governing sensation, decision-making, storage, and voiding. Urodynamic testing will be paired with imaging to link network behavior to specific symptoms.

The team will add diffusion MRI and tractography to reconstruct white matter pathways that carry signals between cortical areas and the brainstem. Investigators will test whether damage in these tracts explains altered brain activity and clinical severity beyond what is visible on routine structural scans. This integrative approach aims to show how discrete lesions disrupt the neural “conversation” required for bladder control.

All stroke participants will receive 12 weeks of TSCS delivered through skin-surface electrodes over the spine to influence circuits mediating bladder function. Imaging and urodynamics will be repeated after therapy to determine whether baseline networks or treatment-related connectivity changes align with improvement. Earlier pilot work by the team found reduced incontinence in many patients, but responses varied, motivating a predictive biomarker panel to reduce trial-and-error.

The study, Functional and Structural Brain Connectivity Alterations in Post-Stroke Lower Urinary Tract Dysfunction, is supported by the National Institute of Diabetes and Digestive and Kidney Diseases, part of the National Institutes of Health (R01DK144402). Insights may also inform individualized neuromodulation for bladder dysfunction linked to traumatic brain injury, neurodegenerative disease, and spinal cord injury.

“Bladder dysfunction after stroke can have a profound effect on a person’s independence, dignity, and quality of life, yet treatment is often focused on the bladder rather than the neurological injury that caused the problem. This grant gives us an opportunity to understand the condition at its source and move toward treatments selected for each patient’s individual pattern of brain injury,” said Evgeniy Kreydin, MD, adjunct assistant professor of clinical urology.

“This project reflects the promise of neuroimaging to connect what we see in the brain with meaningful improvements in patients’ lives. By identifying the biological features that influence treatment response, the team is working toward a future in which rehabilitation and neuromodulation therapies can be tailored to the individual rather than applied through a one-size-fits-all approach,” said Arthur W. Toga, PhD, director of the Stevens INI.

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