Joe D Mobley

Incidence and Predictors of Complications With Sacral Neuromodulation

OBJECTIVES To determine the incidence and predictors of complications with sacral nerve stimulation (SNS). METHODS A prospective, longitudinal analysis of all patients treated with SNS was performed to define the incidence of complications and identify the predictors of these adverse events (AEs). All patients underwent staged SNS placement with the InterStim device for treatment of refractory voiding dysfunction. The patients were followed up for evidence of AEs and device efficacy. The patient and device variables were examined statistically for evidence of predictive value. RESULTS From September 2001 to March 2008, 221 patients with a mean age of 48.8 years underwent SNS lead placement for the treatment of intractable urinary urgency/frequency (n = 121), urge incontinence (n = 63), or urinary retention (n = 37). Of this group, 202 patients (91.4%) experienced a >50% improvement in symptoms and underwent implantable pulse generator placement. At a mean follow-up of 36.9 months, 67 patients (30.3%) had experienced AEs (pain in 6, elective removal in 10, lack of efficacy in 11, trauma in 18, infection in 7, hematoma in 3, and lead migration in 12) requiring 44 lead revisions and 47 implantable pulse generator revisions. The significant predictors of AEs included a history of trauma (P < .001), a change in body mass index class (P < .001), enrollment in a pain clinic (P = .008), the duration of follow-up (P = .002), and a history of AEs (P < .001). CONCLUSIONS The results of our study have shown that SNS is an effective treatment for patients with intractable voiding dysfunction. Complications are not uncommon but can be minimized with better patient selection.

Sacral Nerve Stimulation for Refractory Overactive Bladder in the Elderly Population

PURPOSE We determined the long-term outcome of sacral nerve stimulation for refractory overactive bladder in the elderly population. MATERIALS AND METHODS We performed a prospective longitudinal study to better characterize the outcome of sacral nerve stimulation in female patients 70 years old or older with refractory overactive bladder. Demographic and perioperative data were recorded. Patients were followed postoperatively for evidence of successful stage conversion, device durability and efficacy, and postoperative complications. Patients were retrospectively compared to a cohort of female patients younger than 70 years with refractory overactive bladder. Statistical analysis was performed. RESULTS Between July 2001 and February 2008, 19 elderly female patients with refractory overactive bladder underwent stage 1 lead placement. Of the patients 17 (90%) who reported greater than 50% improvement in symptoms based on a 1-week followup voiding log underwent implantable pulse generator placement. No intraoperative or immediate postoperative complications were noted. At a mean followup of 48.5 months 11 patients (65%) had a functional implantable pulse generator with greater than 50% objective improvement over baseline. Compared to matched patients younger than 70 years elderly patients had a similar conversion rate and adverse events but were significantly more likely to undergo device removal (p = 0.018). CONCLUSIONS Based on our experience elderly patients have a high conversion rate, few adverse events, and a high level of device efficacy and durability with sacral nerve stimulation. Although more mature multicenter data are needed, it appears that sacral nerve stimulation in geriatric patients is safe and efficacious, and should be judiciously offered to those with refractory voiding symptoms.

SACRAL NEUROMODULATION FOR THE TREATMENT OF REFRACTORY VOIDING DYSFUNCTION IN THE ELDERLY POPULATION

urodynamic and immunohistochemical effect in acetic acid (AA) induced bladder hyperactivity in rats. METHODS: LPs (1 ml), BoNT-A (20 unit/1 ml saline), or BoNT-A encapsulated in LPs (Lipotoxin; 20 unit BoNT-A/1 ml LPs) were administered into the bladder and retained for 1 hour on day 1 after baseline cystometrograms (CMGs). Continuous CMGs were performed on day 1 by filling the bladder with saline, and day 8 by filling the bladder with saline followed by 0.3% AA. The bladder was then harvested. CMGs parameters, histology, SNAP25 and CGRP expression by western blotting or immunostaining were measured. RESULTS: Intercontraction interval (ICI) was 57.2% and 56.0% decreased after intravesical instillation of AA in the LPs and BoNT-A pretreated rats, respectively. However, rats which received Lipotoxin showed a significantly reduced response (ICI 21.1 % decrease) to AA instillation. In addition, Lipotoxin pretreated rats had a significant decrease in inflammatory reaction and SNAP-25 expression and increase in CGRP immunoreactivity compared with LPs or BoNT-A pretreated rats. CONCLUSIONS: Intravesical Lipotoxin administration cleaved SNAP-25 and inhibited CGRP release from afferent nerve terminals, and blocked the cystometric changes induced by acetic acid induced irritation. These results support the LPs as an efficient vehicle for delivering BoNT-A without the need for injection and avoid effect on the detrusor.