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Updated: Feb 25, 2026

Detrusor Underactivity Model in Rats by Conus Medullaris Transection
Published on: August 28, 2020
Are patients with bladder oversensitivity different from those with urodynamically proven detrusor overactivity in
Sung-Lang Chen1, Soo-Cheen Ng2, Yu-Hui Huang3
1School of Medicine, Chung Shan Medical University, Taichung, Taiwan, ROC; Department of Urology, Chung Shan Medical University Hospital, Taichung, Taiwan, ROC.
Background:
To determine if there are clinical and urodynamic (UD) differences between female overactive bladder (OAB) patients with bladder oversensitivity (BO) and detrusor overactivity (DO) via a much lower filling rate.
Methods:
In total, 205 patients with OAB symptoms were recruited for this study. During filling cystometry, the bladder was filled at a more "physiological" rate of 20 ml/min. All patients underwent a complete urogynecological evaluation including detailed history, physical examination, urinalysis, pad test for quantification of urine leakage, 3-day frequency-volume chart (FVC) documentation, and completion of a UD study.
Results:
The overall incidence of BO was 34.2% and that of DO was 65.8%. The first desire to void (FDV) in patients with BO and DO were at filling of 117.47 ± 21.68 ml and 135.23 ± 22.88 ml, respectively (p < 0.05). Maximal cystometric capacities (MCC) in patients with BO and DO were recorded at 259.44 ± 33.87 ml and 265.32 ± 44.05 ml (p > 0.05). A receiver operating characteristic (ROC) curve was used to find the cut-off values of FDV for sensitivity and specificity in patients diagnosed with DO. Area under the curve (AUC) was 0.702 (p < 0.005, 95% confidence interval: 0.626-0.779) if FDV was determined as more than 127 ml. Patients with BO experienced significantly increased daytime urinary frequency and nocturia symptoms (<0.05). Patients with DO had a significantly higher prevalence of urgent urinary incontinence (p < 0.05). In this study, a higher FDV and higher body mass index (BMI) were correlating factors for OAB patients with DO after multiple logistic regression analysis.
Conclusion:
Patients with BO seemed to be on a different spectrum compared to those with DO and also had different symptom-specific and associative factors. It was also found that FDV could be good predictive indicator for detecting DO at a low filling rate.
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