عليرضا امينيان

The Lower urinary tract has two responsibilities: storing and voiding urine. Underactive bladder syndrome causes urine retention and incomplete voiding, which cause infections and liver failure. The main problem of pudendal nerve trunk stimulation is the co-activation of the external sphincter muscle, which is innervated directly by the motory fibers of the pudendal nerve. This research aimed to investigate selective stimulation methods in order to activate the bladder contraction reflex and not activate the external sphincter muscle. This thesis investigated the possibility of selective stimulation of sensory fibers of the pudendal nerve trunk by functional electrical stimulation using different pulse shapes and measurements of intravesical and EUS pressure. Cats were used because of their high functional similarity in the lower urinary tract compared to humans. Examined pulse shapes were quasi-trapezoidal, prepulse and slowly rising pulse. Effects of parameters such as amplitude, pulse width and exponential order in pulse shapes in efficiacy of selective stimulation were investigated. Using statistical tests, the bladder and EUS pressure responses to stimulations were eva‎luated and compared. Results of the one-way unpaired t-test test showed significant differences in effects of amplitude, pulse width and exponential order of pulse shape in activation of EUS muscle in three cats (P-value<0.05). Stimulation using Quasi-trapezoidal, prepulse and slowly rising pulses evoked 24.86%, 16.92% and 24.20% less EUS pressure AUC than stimulation using rectangular pulse, respectively. All three examined pulse shapes showed promising results in selective stimulation of sensory fibers of the pudendal nerve trunk with the correct amplitude, pulse width and exponential order.

كنترل مثانه , تحريك الكتريكي عملكردي , عصب پودندال , تحريك انتخابي , پالس تحريك انتخابي

‌Bladder Control , Functional Electrical Stimulation , Pudendal Nerve , selective Stimulation , , Pulse shape Based selective Stimulation

Alireza Aminian

Abbas Erfanian Omidvar