Methods
We retrospectively reviewed the medical records of patients with POP who underwent pelvic reconstructive surgical operation in our institution, a tertiary hospital, from April 2005 to March 2011. Inclusion criteria included stage 3 or stage 4 prolapse, as defined by the International Continence Society (ICS) Pelvic Organ Prolapse Quantification system. Patients who had prior incontinence surgical operation, did not undergo preoperative urodynamic and cystoscopic testing, and had no ability to complete the questionnaires were excluded. Oral or written informed consent was obtained from all patients before the operations for POP correction. The present study was approved by the ethics committee of the study hospital (no. 101-1633B).
The routine preoperative evaluation of patients with severe POP in our institute included general and obstetric histories, urine analysis and culture, voiding diary, 1-hour pad test, neurological and pelvic examinations, site-specific prolapse staging using the Pelvic Organ Prolapse Quantification system, and multichannel urodynamic testing with pessary test. Patients were interviewed regarding the presence of LUTS, as described by Liang et al, using a structured urogynecological questionnaire. In addition to the items on LUTS, we asked the patients if they experienced any pelvic symptoms, including a protruding vaginal mass, bearing-down sensation, backache, dyspareunia, vaginal bleeding, or constipation.
Urodynamic stress incontinence was defined as the involuntary leakage of urine during increased abdominal pressure in the absence of detrusor contraction on filling cystometry. Detrusor overactivity was diagnosed when a patient had involuntary detrusor contractions during filling cystometry that might or might not lead to urinary leakage. BOO was defined as a maximal flow rate of less than 12 mL/second (voided volume in excess of 100 mL), with detrusor pressure at a maximal flow rate greater than 20 cm H2O. Diagnostic urethrocystoscopy was performed by a single investigator to evaluate the bladder for the presence and severity of trabeculation during surgical operation. Using the modified grading system of El Din et al, we classified the severity of BT as 0 (none), 1 (slight), 2 (moderate), 3 (severe), and 4 (severe, with diverticula). The terminology used in this article conforms to the recommendations of the ICS, unless otherwise stated.
Statistical Analysis
LUTS, demographic, and urodynamic data were analyzed in relation to BT. The data are summarized as mean (SD) or number (percent), as appropriate. Continuous data were analyzed using Student's t test or Mann-Whitney U test, and proportions were compared using Fisher's exact test. Logistic regression was used to analyze the associations between various potential risk factors and BT. Appropriate odds ratios (95% CIs) were calculated. The potential risk factors included LUTS, pelvic floor symptoms, demographic and urodynamic data, ICS stage 3 or stage 4 prolapse, and prolapse of the anterior, apical, and posterior vaginal compartments. Probability values less than 0.05 were considered statistically significant.