ABSTRACT
Objective Objective To evaluate the effects of a new type of tibial nerve microstimulator on the micturition reflex in cats.Methods From March to May in 2017,the implantable wireless driver micro-stimulator was implanted around the tibial nerve in 9 α-chloralose anesthetized domestic shorthairs cats (2.5-3.5 kg,6-12 months old).The stimulator was placed near the neurovascular bundle parallel to the tibial nerve and its cathode perpendicular to the cushion.The intensity which can induce toe movement was defined as threshold (T).The ureters were isolated via an abdominal incision.The ureters were cut and drained externally.The bladder was inserted via a double lumen catheter through the urethra.The catheter was then secured by a ligature around the urethra.One lumen of the catheter was used to infuse the bladder with either 0.9％ normal saline (NS) or 0.25％ AA at a rate of 1 to 2 ml/min after connecting to a pump.The other lumen was connected to a pressure transducer to measure the bladder pressure.The bladder capacity was used to test the inhibitory effect of the stimulator.After the appearance of the first large-amplitude (＞ 30 cmH2O) bladder contraction,the bladder infusion was stopped.First,after emptying the bladder,2 or 3 cystometrograms with NS were performed without stimulation to obtain the control bladder capacity.After the bladder was stabilized,TNS (6 Hz,1-2 T) was applied during 2 sequential cystometrograms.Second,after emptying the bladder,0.25 ％ AA was infused into the bladder to irritate and induce bladder overactivity.After the bladder stabilized,TNS (6 Hz,1-2 T) was applied again during 2-3 sequential cystometrograms.If bladder capacity increased significantly,the stimulationhad an inhibitory effect on the micturition reflex.Results During normal saline infusion,the bladder baseline was (17.03 ± 4.10) ml.TNS at 1T did not change the bladder capacity [(18.56 ±0.81)ml] (P ＞0.05).TNS at 2T significantly increased the bladder capacity [(25.05 ± 1.19) ml] (P ＜ 0.05).Compared to normal saline infusion,bladder overactivity was irritated by the intravesical infusion of 0.25％ acetic acid,which significantly reduced the bladder capacity [(9.34 ± 0.75) ml] (P ＜ 0.05).Compared to acetic acid infusion,TNS at 1T did not change the bladder capacity [(11.32 ± 0.82) ml] (P ＞ 0.05).TNS at 2T significantly increased the bladder capacity [(14.82 ± 1.15) ml] (P ＜ 0.05).Conclusions The implantable wireless driver tibial nerve micro-stimulator appears to be effective in inhibiting the micturition reflex during physiologic and pathologic conditions.The implantable wireless driver tibial nerve microstimulator was excepted to be used to treat overactive bladder (OAB).
ABSTRACT
PURPOSE: The goal of this study was to establish typical value ranges (TVRs) and to analyze typical signal patterns (TSPs) of the initial cough (cough before bladder filling) for quality control in urodynamic studies. METHODS: A total of 539 urodynamic traces from patients with neurogenic bladder obtained over the course of a year were retrospectively reviewed. The TVRs for cough amplitude in measurements of the intravesical pressure (P(ves)), abdominal pressure (P(abd)), and detrusor pressure (P(det)) during the initial cough were established. We used the 95% range as a reference range for all parameters. Cough spikes in P(det) were described and classified, and the reasons for different patterns of cough spikes were established. The quality of all the cystometry traces was checked, and we also present remedial actions for inappropriate cough spikes. RESULTS: The cough amplitudes in the measurements of P(ves) and P(abd) were similar, with 95% of measurements falling within the following ranges: 4–62 cm H2O and 3–70 cm H²O, respectively, in supine position and 9–95 cm H²O and 8–98 cm H²O, respectively, in sitting position. For Pdet, the cough amplitude ranged from −38 to 25 cm H²O in supine position and from −44 to 41 cm H²O in sitting position. The cough spikes for P(det) were classified as follows: type I, P(det) pressure exhibited a minimal change (5 cm H²O) was observed for P(det); and type III, biphasic spikes were observed for P(det). Type I coughs were found to have more high-quality traces (P<0.01). CONCLUSIONS: TVRs for the initial cough test among neurogenic patients were established in order to provide guidelines for quantitative quality control. The TSPs for the initial cough signal were described, and the presence of a high-quality cough signal may be recommended as a component of quality control in urodynamic measurements.