A pilot study of bladder voiding with real-time MRI and computational fluid dynamics

Abstract

Lower urinary track symptoms (LUTS) affect many older adults. Multi-channel urodynamic studies provide information about bladder pressure and urinary flow but offer little insight into changes in bladder anatomy and detrusor muscle function. Here we present a novel method for real time MRI during bladder voiding. This was performed in a small cohort of healthy men and men with benign prostatic hyperplasia and lower urinary tract symptoms (BPH/LUTS) to demonstrate proof of principle; The MRI urodynamic protocol was successfully implemented, and bladder wall displacement and urine flow dynamics were calculated. Displacement analysis on healthy controls showed the greatest bladder wall displacement in the dome of the bladder while men with BPH/LUTS exhibited decreased and asymmetric bladder wall motion. Computational fluid dynamics of voiding showed men with BPH/LUTS had larger recirculation regions in the bladder. This study demonstrates the feasibility of performing MRI voiding studies and their potential to provide new insight into lower urinary tract function in health and disease.

Why upright standing men urinate more efficiently than in supine position: A morphological analysis with real‐time magnetic resonance imaging

“…Furthermore, only luminal images are obtained, which do not allow for visualization of movements of pelvic anatomical structures. On the other hand, rtMRI is considered to be an ideal tool to capture dynamic changes of pelvic floor muscles, intestines, and soft tissues around organs with little burden to the subject 5,6 . However, previous studies that utilized rtMRI were done in the supine position, which may not reflect physiological human micturition.…”

“…Real-time magnetic resonance imaging (rtMRI) is a powerful modality to visualize movements of muscular structures in a noninvasive manner. 5,6 Hocaoglu et al 7 reported about anatomical changes in the lower urinary tract (LUT) that occured during urination in a supine position, whereas Nishio et al 8 conducted a similar study on patients in a lateral lying position using rtMRI. Unfortunately, those studies utilized a conventional MRI system, which could only perform examinations with the subject in a resting position.…”

Triboelectric Nanogenerators for Therapeutic Electrical Stimulation

“…Action potentials travel down the pelvic nerve from the CNS, and stimulate the contraction of the detrusor muscles comprising the bladder walls, which induces micturition. [ 280,281 ] The pelvic nerve is the main parasympathetic nerve that runs through the lower urinary tract, and it controls many functions in this area as well as innervates a number of muscles. It has been shown that through pelvic nerve ES, certain muscles controlling bladder function can be activated, thus enabling researchers to control bladder function.…”

MRI Evaluation of Patients Before and After Interventions for Benign Prostatic Hyperplasia: An Update

“…At present, dedicated prostate MRI is not indicated in the preprocedural assessment of BPH [18] in the absence of a clinical suspicion for prostate cancer that may otherwise warrant performing prostate MRI [19]. However, real-time MRI has recently been described as an alternative to urodynamic evaluation [20] and holds potential for the workup of patients with BPH.…”