Micturition by functional magnetic stimulation in dogs: a preliminary report

The effectiveness of functional magnetic stimulation (FMS) technology on bladder contraction and bladder emptying was evaluated in ten normal neurologically intact male dogs. In seven animals, FMS of the bladder was performed by using a commercially available magnetic coil (non-water-cooled) for stimulating the sacral nerves or over the suprapubic region. With sacral stimulation, the mean change in bladder pressure (Pves) was 68.0 +/- 12.96 cm H2O; with suprapubic stimulation, the mean change in Pves was 40.7 +/- 8.08 cm H2O. This change in Pves by sacral stimulation was higher than suprapubic stimulation (P < 0.01). In three additional animals, voiding was demonstrated by using a specialized water-cooled magnetic coil and by stimulating the sacral nerves with an intermittent stimulation sequence. Voiding occurred in all three animals and was reproducible. In summary, FMS of the bladder has the potential to be a useful non-invasive technology for bladder emptying and bladder training in patients with neurogenic bladder.