Sacral neuromodulation for treatment of overactive bladder: a review

Abstract

Sacral neuromodulation (SNM) therapy is an established third line therapeutic option for the treatment of urgency urinary incontinence, urgency-frequency and chronic non-obstructive urinary retention. The continuous stimulation of the sacral root S3 with an electrode connected to an implanted pulse generator (IPG) may influence detrusor and sphincter activity and improve lower urinary tract symptoms. The mechanism of action is not completely understood and seems to be based on the modulation of spinal cord reflexes and brain centers involved in lower urinary tract function. It is implanted with a minimally invasive technique that can be performed under local anesthesia and includes a test phase that precedes the definitive implantation of the pulse generator. When compared to the standard pharmacological therapy, neuromodulation promoted better results both in the partial improvement of overactive bladder (OAB) symptoms and total continence. Moreover, sexual function, quality of life and depressive symptoms may also improve in patients with OAB that undergo SNM. However, SNM is associated with significant rates of adverse events and need for surgical revisions, requiring continuous medical attention.