Purpose: We reviewed the literature on the application of various devices and techniques for the electrical stimulation treatment of lower urinary tract dysfunction with respect to mechanism of action and clinical outcome.
Materials and methods: A systematic review was done in PubMed of publications on intravesical stimulation, direct bladder stimulation, stimulation of the pelvic and pudendal nerves, transcutaneous-electrical nerve stimulation, stimulation of the sacral spine and roots, and lower limb stimulation.
Results: It is difficult truly to compare different treatment modalities because there are hardly any randomized placebo controlled studies. Also, there is considerable variety in treatment parameters and schedules reported as well as in criteria for success. Nevertheless, it can be said that electrical neurostimulation and neuromodulation result in a 30% to 50% clinical success on an intent to treat basis. Influencing lower urinary tract innervation at the level of sacral roots seems successful in neurological and nonneurological cases. It has the advantage of pretesting possibilities to improve patient selection and treatment outcome with the obvious drawback of invasiveness. Noninvasive techniques lack screening tests, making patient selection a matter of trial and error, and when there is success patients almost always need maintenance therapy.
Conclusions: Randomized clinical trials to compare different techniques and evaluate placebo effects are urgently needed, as are further studies to elucidate modes of action to improve stimulation application and therapy results. The introduction of new stimulation methods may provide treatment alternatives as well as help answer more basic questions on electrical neurostimulation and neuromodulation.