Pd59-06 a Prospective Feasibility Study to Differentiate Sacral Neuromodulation Lead Contacts Using Motor and Sensory Thresholds and Locations of Sensation During, Immediately After, and Up to One Month Following Implantation

You have accessJournal of UrologyUrodynamics/Lower Urinary Tract Dysfunction/Female Pelvic Medicine: Neuromodulation (PD59)1 May 2024PD59-06 A PROSPECTIVE FEASIBILITY STUDY TO DIFFERENTIATE SACRAL NEUROMODULATION LEAD CONTACTS USING MOTOR AND SENSORY THRESHOLDS AND LOCATIONS OF SENSATION DURING, IMMEDIATELY AFTER, AND UP TO ONE MONTH FOLLOWING IMPLANTATION Tianyu He, Christopher Hornung, Michael D. Evans, Dwight E. Nelson, and Nissrine Nakib Tianyu HeTianyu He , Christopher HornungChristopher Hornung , Michael D. EvansMichael D. Evans , Dwight E. NelsonDwight E. Nelson , and Nissrine NakibNissrine Nakib View All Author Informationhttps://doi.org/10.1097/01.JU.0001009544.34256.8a.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Proper positioning of sacral neuromodulation (SNM) leads relies on pelvic floor motor thresholds (PFMT), sensory thresholds (ST), and the location of sensation (LOS). This clinical feasibility study aims to gauge the functional utility of these physiomarkers for differences between lead contacts and changes over time. METHODS: We enrolled 8 participants with Axonics SNM devices. PFMT was tested post-SNM implantation under anesthesia. ST was tested at 3 time points: immediately post-op (PO); pre-release from hospital (PR); and during follow-up (FU, 1-4 weeks post-op). All thresholds were tested using 210 us pulse width and 14 Hz bipolar stimulation at therapy contacts: 0-, 3+; 1-, 3+; 2-, 0+; and 3-, 0+. ST and PFMT were compared by contact and time period using linear mixed-effects models. LOS was assessed after each ST as in Vaganée (2018) by patients marking coordinates on a pelvic map. Our primary hypothesis was that PFMT, ST, and LOS across contacts would differ and change over time, addressing the question: Are these measurements useful to differentiate the quality of lead locations? RESULTS: Significant differences were found in PFMT across contacts. Distal contact stimulation (0-, 3+; mean=1.0 mA) had higher PFMT than proximal stimulations (2-, 0+; 3-, 0+; mean=0.5 mA and 0.5 mA, respectively; p<0.05). In contrast, ST showed no differences across contacts or time (PO to PR and FU). LOS was highly variable both across patients and time. Within-patient LOS for a lead spanned large areas (max=9 map units, mean=1.8, SD=2.0). LOS showed large changes after surgery (PO vs PR) with identical coordinate in only 12% of tests (7/60) and within one adjacent coordinate in only 33% of tests (20/60). LOS changes continued from PR to FU, remaining the same in only 13% of tests (4/32) and within one adjacent coordinate in only 22% (7/32). CONCLUSIONS: Results affirm the utility of PFMT using bipolar stimulation in distinguishing therapy contacts. ST showed no differences over time or across contacts. The large variability in LOS suggests limited use in identifying differences across contacts or time immediately post-surgery. It is premature to attribute differences in LOS to differences in lead position. Contributing factors to the lack of ST or LOS effects may include the small sample size, patient unfamiliarity with novel paresthesias, use of bipolar stimulation, and the absence of efficacy outcome-based data analysis. Source of Funding: Sponsored in part by funds from the Dr. Gerald W. Timm Endowed Professorship in Neurourology and Urologic Engineering. Disclosures: Authors have no conflict of interest to declare © 2024 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 211Issue 5SMay 2024Page: e1223 Advertisement Copyright & Permissions© 2024 by American Urological Association Education and Research, Inc.Metrics Author Information Tianyu He More articles by this author Christopher Hornung More articles by this author Michael D. Evans More articles by this author Dwight E. Nelson More articles by this author Nissrine Nakib More articles by this author Expand All Advertisement PDF downloadLoading ...