Hypothesis / aims of study
The main challenging urological goals in children with neurogenic bladder dysfunction are to protect the upper urinary tract from the effect of high-pressure reflux and to achieve urinary continence. [1,2] Management should focus on ensuring bladder empting, attaining safe bladder storage pressure and capacity, and adequate sphincteric outlet resistances. [1,2] Surgical therapy could be considered when non-surgical therapy such as anticholinergic medication and intermittent catheterization fails. In the past twenty-five years our institution has built experience in bladder outlet procedures (BOPs) such as bladder neck sling (BNS) and bladder neck reconstruction (BNR). This study aimed to evaluate the long-term outcome on continence of BOPs in children with urinary incontinence secondary to neurogenic sphincteric incompetence.
Study design, materials and methods
We retrospectively reviewed all children who underwent a BOP between 1992 and 2017 in our institution. The principles of Helsinki Declaration were followed in lieu of formal ethics committee approval. A BOP was combined with bladder augmentation if a low compliant bladder and/or a small capacity insufficiently responsive to anticholinergics was seen. Often the BOP was combined with the creation of a continent urinary conduit, most commonly an appendicovesicostomy. We divided the BOPs in two types: BNR and BNS. A BNR was performed using one of the three techniques described by Mitchell, Pippi Salle or Young-Dees. The choice of technique depended on the preference of the surgeon. We chose to merge the results of those techniques, because they all increase the bladder outlet resistance by lengthening and narrowing the urethra with tubularization of the trigone. The BNS procedure was based on co-aptation, elevation and narrowing the urethra by suspension of the bladder neck with an autologous fascial strip to the pubic symphysis. Continence at the end of follow up was the primary endpoint, defined as ‘dry’ when there was an interval of a minimum of 4 hours without urinary leakage. Secondary outcomes were continence within 1 year postoperative, and reinterventions. Non-parametric tests were used for statistical analysis (significance p<0.05).
Results
A total of 60 children underwent a BOP, at a median age of 11.6 (IQR 7.8-13.9) years. The etiologies of neurogenic urinary incontinence were myelomeningocele, VACTERL-associated cause, and sacrococcygeal teratoma. Forty-three (71.7%) patients underwent a BNS and in 17 (28.3%) a BNR. In Table 1 the patient characteristics are shown. Dry rate within one year was 38.3%. After a median follow up of 10.4 (IQR 6.5-15.5) years, 76.7% of all children were dry. Twenty-five children (41.7%) needed reintervention(s) after a median follow-up of 1.0 (IQR 0.7-3.5) years, including redo of the BOP, other type of outlet procedure, bulking agents, bladder augmentation and bladder neck closure (Figure 1).
Interpretation of results
Although techniques and insights have changed over the years, achieving continence in children with neurogenic sphincteric incompetence is still a challenge. The choice of a BOP with or without concomitant surgery such as bladder augmentation and continent urinary conduit is influenced by the patient’s needs, gender, bladder function, and the surgeon’s preference. Because it concerns a young patient population, awareness of the outcome on the long term is important, but unfortunately reports are sparse. Those long-term results are valuable for patient counseling and to create awareness in patients and parents about what to expect. Future studies should use a clear definition of urinary incontinence and add validated patient-reported outcome measurements to evaluate the effect on symptoms and quality of life.