Colorectal Dis. 2020 Oct 3. doi: 10.1111/codi.15390. Online ahead of print.

Charles Knowles ¹, Stefan de Wachter ², Stefan Engelberg ³, Paul Lehur ⁴, Klaus E Matzel ⁵, Lance Zirpel ⁶, European SNM Expert group

• European SNM Expert group: 

Maria Paola Bertapelle, Emmanuel Chartier-Kastler, Tom Dudding, Karel Everaert, Philip van Kerrebroeck, Charles H Knowles, Paul A Lehur, Lilli Lundby, Klaus E Matzel, Arantxa Muñoz-Duyos, Mona B Rydningen, Michael Sørensen, Stefan de Wachter

Author information

• ¹Centre for Neuroscience, Surgery & Trauma, Blizard Institute, Queen Mary University of London & Barts Health NHS Trust London, UK.
• ²Department of Urology, University Hospital Antwerpen; Faculty of health sciences, University Antwerpen, Belgium.
• ³Medtronic Intl Sarl, Tolochenaz, Switzerland.
• ⁴Coloproctology Unit. Ospedale Regionale di Lugano, Lugano, Switzerland.
• ⁵Chirurgische Klinik, Universität Erlangen, Germany.
• ⁶Global Neuromodulation Research, Medtronic Inc, Minneapolis, Minnesota, USA.

Abstract

Aim: Sacral neuromodulation (SNM)is a widely adopted treatment for overactive bladder, non-obstructive urinary retention and faecal incontinence. In the majority, it provides sustained clinical benefit. However it is recognized that even for these patients, stimulation parameters (such as amplitude, electrode configuration, frequency and pulse width) may vary at both initial device programming and at reprogramming, the latter often being required to optimize effectiveness. Although some recommendations exist for SNM programming, the scientific data to support them are understood by few clinicians.

Methods: Narrative review of literature covering some of the science behind stimulating a mixed peripheral nerve and available preclinical data in the field of SNM. The review covers electrode configuration, amplitude, frequency, pulse width and cycling considerations. The review is targeted at clinicians with an interest in the field and does not seek to provide exhaustive detail on basic neuroscience.

Results & conclusions: Knowledge of the science of neuromodulation provides some guiding principles for programming but these are broad. These principles are not refuted by preclinical data but specific parameters in clinical use are not strongly supported by animal data, even after the limitations of small and large animal models are considered. The review presents a shortlist of programming principles on a theoretical basis but acknowledges that current practice is as much derived from evolved experience as science.