In its simplest and most often used form, InterStim® Therapy, applies electrical stimulation unilaterally to the sacral spinal nerve (SN, S3) as an established clinical treatment modality for patients with overactive bladder [1]. Scheepens and colleagues [2] reported that bilateral stimulation was superior to unilateral sacral neuromodulation in only 2 out of 25 patients. Retrospective studies, however, have also suggested that patients receiving bilateral stimulation are more likely to show a significant symptomatic improvement [3–5]. Preclinical testing is consistent with this clinical finding. Bilateral stimulation results in a stronger bladder inhibition than unilateral stimulation when tested in cats [6,7] and pigs [8].
In the present study we attempt to define and characterize responses to several forms of bilateral SN neuromodulation using end-points related to bladder control. We characterize the effectiveness of three stimulation modalities: 1) bilateral stimulation...
