Denervation techniques

The bladder can be denervated at several levels: centrally, at the level of the sacral nerves; peripherally, on the pelvic nerves; or in the bladder, by cutting the relevant structures, by injecting substances toxic to nerves, or by hyperbaric bladder distension. These procedures target the sensory or motor nerves to weaken or to interrupt the detrusor reflex arc. Most of the procedures introduced previously, e.g. bladder trans-section by open operation, endoscopic or transvesical phenolization, hyperbaric bladder distension, and peripheral denervation of the bladder, have now been abandoned. Although some of these techniques had a high initial success rate in abolishing detrusor overactivity and in controlling incontinence, the relapse rate within 18 months approached 100%. In the early 1950s, much of the denervation surgery was performed on sacral roots and nerves. Nowadays, sacral de-afferentiation of the bladder by dorsal sacral root rhizotomy of S2-S5, using specialized techniques, either intradurally or at the conal level, has proved to be a very effective procedure for patients with spinal cord injuries and detrusor hyper-reflexia, functional low compliance and reflex incontinence, which cannot be managed by any other means. In conclusion, although in approximately 90% of patients the symptoms of an overactive bladder will be eliminated or improved by conservative methods of treatment, bladder denervation procedures still have a place in the management of these patients. In particular, with these procedures a low-pressure bladder system can be obtained and urinary continence restored in patients with complete suprasacral spinal cord lesions.