Bladder outlet obstruction is a common urological condition. We aimed to summarize available evidences about bladder outlet obstruction-induced molecular and morphological alterations occurring in human bladder. We performed a literature search up to December 2017 including clinical and preclinical basic research studies on humans. The following search terms were combined: angiogenesis, apoptosis, bladder outlet obstruction, collagen, electron microscopy, extracellular matrix, fibrosis, hypoxia, histology, inflammation, innervation, ischemia, pressure, proliferation, remodeling, suburothelium, smooth muscle cells, stretch, urothelium. We identified 36 relevant studies. A three-stages model of bladder wall remodeling can be hypothesized involving an initial hypertrophy phase, a subsequent compensation phase and a later decompensation. Histological and molecular alterations occur in the following compartments: urothelium, suburothelium, detrusor smooth muscle cells, detrusor extracellular matrix, nerves. Cyclic stretch, increased hydrostatic and cyclic hydrodynamic pressure and hypoxia are stimuli capable of modulating multiple signaling pathways involved in this remodeling process. Bladder outlet obstruction leads to progressive bladder tissue remodeling in humans. Multiple signaling pathways are involved.

This is a prospective, double-blind, placebo controlled study, based on an original placebo technique, performed to evaluate the efficacy of percutaneous tibial nerve stimulation in female patients with detrusor overactivity incontinence. A total of 35 female patients presenting with detrusor overactivity incontinence that did not respond to antimuscarinic therapy were randomly assigned to percutaneous tibial nerve stimulation or to a control group. The percutaneous tibial nerve stimulation group (18 patients) was treated with 12 percutaneous tibial nerve stimulation sessions. The control group (17 patients) received an original placebo treatment using a 34 gauge needle placed in the medial part of the gastrocnemius muscle. The sessions lasted for 30 minutes and were performed 3 times weekly as percutaneous tibial nerve stimulation sessions. All patients were evaluated with bladder diaries as well as quality of life scores before and after treatment. Patients showing a reduction in urge incontinence episodes greater than 50% were considered responders. Some patients (1 in the percutaneous tibial nerve stimulation group and 2 in the placebo group) did not complete the study for reasons not related to the technique. Of 17 patients in the percutaneous tibial nerve stimulation group 12 (71%) and of 15 in placebo group 0 were considered responders according to the previously reported definition (p <0.001). Improvement in the number of incontinence episodes, number of voids, voided volume and incontinence quality of life score were statistically significant in the percutaneous tibial nerve stimulation group but not in the placebo group. Percutaneous tibial nerve stimulation can be considered an effective treatment for detrusor overactivity incontinence with 71% of patients considered responders, while none of those treated with placebo was considered a responder. The relevance of a placebo effect seems to be negligible in this patient population.

Background: Percutaneous Tibial Nerve Stimulation (PTNS) has been proposed for the treatment of overactive bladder syndrome (OAB), non-obstructive urinary retention (NOUR), neurogenic bladder, paediatric voiding dysfunction and chronic pelvic pain/painful bladder syndrome (CPP/PBS). Despite a number of publications produced in the last ten years, the role of PTNS in urinary tract dysfunctions remains unclear. A systematic review of the papers on PTNS has been performed with the aim to better clarify potentialities and limits of this technique in the treatment of OAB syndrome and in other above mentioned urological conditions. Methods: A literature search using MEDLINE and ISI web was performed. Search terms used were “tibial nerve” and each of the already mentioned conditions, with no time limits. An evaluation of level of evidence for each paper was performed. Results: PTNS was found to be effective in 37-100% of patients with OAB, in 41-100% of patients with NOUR and in up to 100% of patients with CPP/PBS, children with OAB/dysfunctional voiding and patients with neurogenic pathologies. No major complications have been reported. Randomized controlled trials are available only for OAB (4 studies) and CPP/PBS (2 studies). Level 1 evidence of PTNS efficacy for OAB is available. Promising results, to be confirmed by randomized controlled studies, have been obtained in the remaining indications considered. Conclusions: PTNS is an effective and safe option to treat OAB patients. Further studies are needed to assess the role of PTNS in the remaining indications and to evaluate the long term durability of the treatment. Further research is needed to address several unanswered questions about PTNS.