Karl-Erik Andersson led the peer-review process as the Associate Editor responsible for the paper.
High-frequency micro-ultrasound: A novel method to assess external urethral sphincter function in rats following simulated birth injury
Version of Record online: 16 JAN 2014
© 2014 Wiley Periodicals, Inc.
Neurourology and Urodynamics
Volume 34, Issue 3, pages 264–269, March 2015
How to Cite
Hakim, L., Endo, M., Feola, A., Soebadi, D. M., Deprest, J., De Ridder, D., Albersen, M. and Van der Aa, F. (2015), High-frequency micro-ultrasound: A novel method to assess external urethral sphincter function in rats following simulated birth injury. Neurourol. Urodyn., 34: 264–269. doi: 10.1002/nau.22555
Conflict of interest: None of the authors have conflict of interests, except Doddy M. Soebadi who is involve in trials and receives speaker honorarium from Astellas Pharma, Glaxo Smith Kline, Bayer, and Pfizer.
- Issue online: 12 MAR 2015
- Version of Record online: 16 JAN 2014
- Manuscript Accepted: 2 DEC 2013
- Manuscript Received: 23 MAY 2013
- Fonds Wetenschappelijk Onderzoek Vlaanderen. Grant Number: 1.8.012.07.N.02
- European Commission. Grant Number: PIAP-GA-2009-251356
- external urethral sphincter;
- high-frequency ultrasound;
- stress urinary incontinence;
- vaginal distension
We evaluated external urethral sphincter (EUS) function using high-frequency micro-ultrasound (US) in rats that were either uninjured (Control, C) or underwent vaginal distension (VD) as a substitute for vaginal birth injury induced stress urinary incontinence (SUI).
Thirteen female nulliparous Sprague–Dawley rats of 12 weeks were divided into two groups, either C (n = 6) or VD (n = 7). Vaginal balloon distension was performed under pentobarbital anesthesia for 4 hours. Five days after the injury, all animals underwent US assessment of the urethra during high-rate bladder filling and urine leakage/voiding. Urinary leakage, the presence, absence, and pattern of EUS bursting during the voiding phase were registered, and pre-determined parameters of intercontraction interval (ICI), length of contraction (LOC), and rate of contraction (ROC) were registered.
Our ultrasound findings consistently showed the presence of rhythmic EUS bursting in all of the C rats (6/6), which were absent in all VD rats (0/7). The mean of ROC, ICI, and LOC in C group were 3.02 ± 0.12 contractions/sec, 471.43 ± 17.9 msec, and 103.41 ± 3.28 msec, respectively.
Pre-determined parameters of LOC, ICI, and ROC during US provide objective and measurable data on EUS function. US showed the total disappearance of EUS bursting in the VD group as compared to the C group. These results indicate that ultrasound testing may become a valuable non-invasive tool in future translational studies to investigate SUI/urethral function in rat models. Neurourol. Urodynam. 34:264–269, 2015. © 2014 Wiley Periodicals, Inc.