Tailoring Stress Incontinence Surgery : “How to install proper diagnostic work-up and individualised treatment”

Abstract

In this thesis a different principle to determine the value of diagnostic parameters and to install the proper, individualized, surgical treatment for stress urinary incontinence is presented. The aim of the first part of this thesis was to evaluate the value of urodynamic investigation (UDI) in the pre-operative work-up of mid-urethral sling (MUS) surgery and to identify risk factors for failure after three different MUS procedures. Mixed urinary incontinence (MUI), previous incontinence surgery and detrusor overactivity (DO) were significantly related to failure of MUS procedures. However there were no predictive urodynamic parameters for failure in patients with MUI or previous incontinence surgery. Then a comparison was made between the risk factors for failure of Tension-free Vaginal Tape (TVT) and Transobturator Tape (TOT) procedures (Monarc and TVT-O). Risk factors for failure were MUI and DO at urodynamics in the TVT group compared to a history of previous incontinence surgery and a low (<20 cm H2O) mean urethral closure pressure at urodynamics in the TOT group. Therefore results of medical history and pre-operative urodynamics can aid in selecting the proper MUS procedure. Decision rules were developed based on medical history and physical examination to predict a high probability group of women with DO and/or a low mean urethral closure pressure (urodynamic risk factors found in the previous studies). The following decision rules could be formulated: women are likely to benefit from pre-operative urodynamics if they: 1) are 53 years of age or older; or 2) have a history of prior incontinence surgery and are at least 29 years of age; or 3) have nocturia complaints and are at least 36 years of age. If pre-operative urodynamics would be omitted in women in the low probability group, in our population, pre-operative urodynamics could be reduced by 29%. Before implementation in clinical practice, these rules should be validated. The concept of the Surgical Therapeutic Index (STI) is introduced to compare TVT and TOT procedures. The STI is defined as the ratio between the cure- and complication rate. Two months after surgery the STI is significantly higher after TOT whereas 12 months after surgery results of STI’s are equal. The explanation is more durable cure rates and declining long-term side effects after TVT procedures. To determine patient expectations regarding wanted and unwanted sequels of MUS procedures a patient preference study (40 patients) combined with a questionnaire study (20 experts) was conducted. Seventeen different sequels were evaluated. Patients and physicians agreed on the most important sequels like cure, improvement and functional complications. Time to resume work after the operation and dyspareunia were among the highest rated sequels in the patient group and should be regarded in pre-operative counselling and future clinical trials. At last the importance of long-term follow-up of surgical procedures is recognized. Therefore a prospective cohort study was performed to compare outcome and quality of life after 2-4 years of two TOT procedures, Monarc and TVT-O. No significant differences were observed in cure rate, complications and quality of life.