The assessment of a novel electrical stimulation waveform recently introduced for the treatment of overactive bladder

Transdermal amplitude modulated signal (TAMS) is a novel electrical stimulus which has been recently introduced for the treatment of overactive bladder (OAB) syndrome. It has been suggested that it has advantages over conventional waveforms by providing more effective penetration of the skin to enhance the efficacy of therapy. As there is no literature which supports this, we performed this study to evaluate potential advantages of the TAMS signal for electrical stimulation of subcutaneous nerves as compared to conventional stimuli. The stimuli were applied on forearms of ten healthy volunteers and electrical parameters of stimuli and sensation measurements were recorded. None of the recorded electrical parameters showed significant differences (paired t-test p ≥ 0.250) between the TAMS and conventional waveforms. Similarly, the mean sensation recorded at motor threshold level and at 50% of maximal motor response level showed no differences (paired t-test p = 0.242 and p = 0.687 respectively). It is unlikely, based on the results of this study, that TAMS provides any enhancement of the efficacy of conventional stimuli. We would recommend that further studies are carried out to clearly demonstrate in man what, if any, advantages the TAMS waveform has over conventional stimulation before it is widely deployed into clinical practice.