Related Experiment Video
Updated: Mar 25, 2026
05:25
Ultrasonography of the Adult Male Urinary Tract for Urinary Functional Testing
Published on: August 14, 2019
20.5K
Biomechanic characterization of normal urethra using uro-dynamic MRI during voiding.
Cody Johnson1, Juan Pablo Gonzalez-Pereira2, Maxwell Kounga1
1Department of Radiology, University of Wisconsin-Madison, Madison, USA.
International Urology and Nephrology
|March 24, 2026
Summary
Uro-dynamic MRI non-invasively assessed urethral biomechanics during voiding. The membranous urethra showed the narrowest lumen and highest resistance, correlating with flow dynamics.
Area of Science:
- Urology
- Biomedical Engineering
- Medical Imaging
Background:
- Dynamic volumetric MRI enables non-invasive assessment of urethral biomechanics.
- This study focused on a single healthy male subject during the voiding process.
Purpose of the Study:
- To evaluate the feasibility of uro-dynamic MRI for analyzing lower urinary tract (LUT) anatomy and function.
- To quantify urethral dimensions and resistance during voiding.
Main Methods:
- Volumetric LUT images acquired using uro-dynamic MRI during voiding.
- Image segmentation using MIMICS to define prostatic, membranous, penile, and bulbous urethral segments.
- Calculation of urethral diameters, length, flow phases, and instantaneous resistances.
Main Results:
- Step-by-step analysis indicated flow variations during initial and terminal phases.
- Time and length-averaged analysis revealed the membranous urethra as the narrowest segment with the highest resistance.
- Strong correlations observed between urethral diameters (prostatic and membranous) and flow rates.
Conclusions:
- Uro-dynamic MRI shows promise for non-invasive assessment of LUT anatomy.
- The technique can provide insights into urethral biomechanics during voiding.
- Further studies can validate these findings in larger cohorts.
Keywords:
Anterior urethraDynamic MRIPosterior urethraUrethral biomechanicsUrethral diameterUrethral resistanceMore Related Videos
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