Advances in the role of sacral nerve neuromodulation in lower urinary tract symptoms

Abstract

Sacral neuromodulation has been developed to treat chronic lower urinary tract symptoms, resistant to classical conservative therapy. The suspected mechanisms of action include afferent stimulation of the central nervous system and modulation of activity at the level of the brain. Typical neuromodulation is indicated both in overactivity and in underactivity of the lower urinary tract. In the majority of patients, a unilateral electrode in a sacral foramen and connected to a pulse generator is sufficient to achieve significant clinical results also on long term. In recent years, other urological indications have been explored.

Neuromodulation of Pelvic Visceral Pain: Review of the Literature and Case Series of Potential Novel Targets for Treatment

“…In 1981, Tanagho and Schmidt subsequently demonstrated that stimulation of the S3 nerve root could be applied to a variety of GU pathologies (eg, incontinence and frequency) by modulating detrusor and sphincter action. 25,54 This research paved the way for the 1997 FDA approval of epidural sacral nerve root stimulation in the treatment of urinary urgency, frequency, urge incontinence, and retention. [54][55][56] The mechanism behind sacral nerve stimulation's (SNS) ability to modulate micturition is still being elucidated.…”

“…described the first successful implantation of a SCS in the sacral spinal cord to initiate voiding in a patient with a spinal cord injury. In 1981, Tanagho and Schmidt subsequently demonstrated that stimulation of the S3 nerve root could be applied to a variety of GU pathologies (eg, incontinence and frequency) by modulating detrusor and sphincter action 25,54 . This research paved the way for the 1997 FDA approval of epidural sacral nerve root stimulation in the treatment of urinary urgency, frequency, urge incontinence, and retention 54–56 …”

“…The mechanism behind sacral nerve stimulation’s (SNS) ability to modulate micturition is still being elucidated. It may activate or reset the somatic afferents involved in sensory processing and the micturition reflex pathways in the spinal cord 54 . Additional theories surmise SNS may interfere with sympathetic signals to the bladder involved in the guarding and vesicosympathetic reflex, which control continence and filling, respectively 54,55 .…”

“…It may activate or reset the somatic afferents involved in sensory processing and the micturition reflex pathways in the spinal cord 54 . Additional theories surmise SNS may interfere with sympathetic signals to the bladder involved in the guarding and vesicosympathetic reflex, which control continence and filling, respectively 54,55 . More recent studies have revealed SNS being correlated with increased activity in the brain (via PET) at the paraventricular gray, which is involved in activation or inhibition of the micturition reflex 54,57 …”

“…SNS has shown consistent efficacy in the treatment of bladder dysfunction, incontinence, urinary retention/frequency, and even with fecal incontinence; 54,56,58–61 it has also shown great promise in treating the symptoms of IC/PBS. Hohenfellner et al 62 .…”