Non-invasive methods to evaluate voiding dysfunction in men are extremely limited. We report here a non-invasive, MRI-based protocol to characterize urethral biomechanics during voiding. All four subjects were able to void in the scanner with high-fidelity, 3D images of the urethra. These images were successfully analyzed for anatomy, function, and biomechanics. Future work will be aimed at furthering these methods and resulting metrics so that they may be applied clinically.

qRT-PCR and Western blot analysis. Functional and morphological changes in mitochondria were examined. In vivo, forty SD rats (6 wks of age) were divided into four groups and bred until twenty weeks: control (CON), High Fat Diet (HFD), HFDþ300 mg/kg/d NAC (HFDþLNAC), and HFDþ900 mg/kg/d NAC (HFDþHNAC)}. At the end of the 20 weeks, blood and bladder smooth muscle samples were collected, and OS and contractile levels were examined.RESULTS: In vitro, high glucose significantly enhanced oxidative stress, inflammation and fibrosis in BSMCs. Moreover, the increase in cytokine expression was accompanied by enhanced NLRP3 expression and the phosphorylation of NF-kB. However, N-acetylcysteine had an inhibitory effect on the expression of ROS/NLRP3/NF-kB and the dissolution of mitochondria in HG-treated BSMCs. In vivo, compared to those in the control group, the mean contractility and frequency of bladder smooth muscles in the HFD group was significantly decreased (p<0.01). The mean contractility in the LNACþHFD group was significantly higher than that in the HFD group (p<0.01). Interestingly, the HNACþHFD group did not show any recovery in muscle contractility but exhibited significantly reduced bladder contractile frequency (p<0.01).CONCLUSIONS: Our findings indicated that high glucoseinduced oxidative stress, inflammation and fibrosis are mainly mediated by the ROS/NLRP3/NF-kB signaling pathways and mitochondrial changes in BSMCs. NAC ameliorated these changes by blocking the ROS/NLRP3/NF-kB signaling pathways and protecting mitochondrial function and morphology.

Studying common urinary conditions such as BPH/LUTS require measuring urine flow in the urethra by invasive techniques. We present a method that uses real-time MR images of the bladder and urethra to quantify urine flow dynamics. Images of the urethra define the anatomical geometry, while images of the bladder inform the flow rate inside the urethra. Coupling MRI with CFD allows the urinary flow simulation inside the urethra providing information about urine velocity, pressure, and wall shear stress non-invasively.

Multi-channel urodynamics is an invasive diagnostic method used to assess bladder biomechanics. MRI-based CFD has shown high potential as a clinical tool primarily focused on cardiovascular flows. In this pilot study, we demonstrate MRI-based CFD as a tool to study urodynamics. Real-time MRI on one subject provided bladder wall surfaces at multiple time points during voiding. We developed a surface mapping algorithm that processes the bladder geometries before inputting them into a CFD simulation. Coupling MRI with CFD successfully visualized and quantified urine flow dynamics. This provides a non-invasive tool to investigate urodynamics in common urological conditions such as BPH/LUTS.

Lower urinary track symptoms (LUTS) affect many older adults. Existing methods to evaluate the lower urinary tract are invasive and provide limited information about changes in bladder anatomy and detrusor muscle function. Use of non-invasive methods for the study of lower urinary tract anatomy and function has been limited. This pilot study demonstrates the feasibility of MRI urodynamics in healthy subjects and in LUTS patients. Future advancements in this study will be aimed at using the data acquired to further deepen the comprehension of the bladder voiding cycle.