Tined Lead Electrode Research Articles

Comparison of surgical techniques for optimal lead placement in sacral neuromodulation: a cadaver study

BackgroundSacral neuromodulation (SNM) is a common treatment for patients with urinary and faecal incontinence. A close contact of the tined lead electrode with the targeted nerve is likely to improve functional outcome.The aim of this study was to compare the position of the SNM lead in relation to the sacral nerve by comparing different implantation techniques.MethodsThis cadaver study was conducted at the Division of Anatomy of Vienna's Medical University in October 2020. We dissected 10 cadavers after bilateral SNM lead implantation (n = 20), using two different standardized implantation techniques. The cadavers were categorized as group A (n = 10), representing the conventional guided implantation group and group B (n = 10), where SNM implantation was conducted with the novel fluoroscopy-guided “H”-technique. The primary goal was to assess the distance between the sacral nerve and the lead placement.ResultsThe electrodes were inserted at a median angle of 58.5° (46–65°) in group A and 60° (50–65°) in group B, without reaching statistical significance. In 8 cadavers, the lead entered the S3 foramen successfully.The median distance of the lead to the nerve did not show a significant difference between both groups (E0: Group A: 0.0 mm vs. Group B: 0.0 mm, p = 0.969; E1: Group A: 0.0 mm vs. Group B: 0.5 mm p = 0.754; E2: Group A: 2.5 mm vs. Group B: 2.5 mm p = 1.000; E3: Group A: 3.5 mm vs. Group B: 4.0 mm p = 0.675). In 2 cases (20%) of the conventional group A, the lead was misplaced and located at the gluteal muscle.Perforation of the presacral fascia was observed in one lead placement in group A and in two placements in group B.ConclusionsBoth standardized implantation techniques may ensure close electrode proximity to the targeted nerve. Misplacement of the electrode was more often observed with the conventional implantation technique.

Sacral neuromodulation for faecal incontinence – 10 years experience and long-term outcomes of a specialized centre

Sacral neuromodulation/sacral nerve stimulation (SNM/SNS) has become the most successful method for treatment of faecal incontinence (FI) in the last 10 years. The high efficiency of SNM is based on the electrical stimulation of the external anal sphincter and moreover the mechanism of action of SNS can be explained by the modulation of somatovisceral reflexes and perceptions of afferent information. Therefore the mechanism of action is more complex in contrast to other methods of treatment. In the Czech Republic, the SNM was implemented for the first time in 2010 with the financial support of the IGA grant of the Ministry of Health of the Czech Republic. Since 2018, two specialized centres for the treatment of FI using the SNM method have been established in the Czech Republic. In the years 20102020, 35 patients were indicated for SNM. The ratio of women to men was 34:1. The mean age at implantation was 62 years (range 4675). Most patients were in the 6th and 7th decade. Two diagnostic procedures were performed in all patients, percutaneous evaluation of the S2S4 sacral nerves, implantation of the Medtronic 3889 28cm stimulation tined lead electrode and its connection to an external stimulator and subsequent subchronic stimulation for 24 weeks. The criteria for permanent neurostimulator implantation were a minimum 50% reduction in the number of FI episodes per week or a 50% reduction in incontinence score. Patients were then implanted with a Medtronic InterStim II 3058 permanent neurostimulator. A permanent neurostimulator was implanted in 33 of 35 patients (94%). No patient died. The complication rate was 11.4%. In 2 patients it was an infectious complication. In one patient malposition of the stimulator occurred after falling down and in one patient we observed lead breakage with subsequent malfunction of the stimulator after falling down. All complications were successfully resolved by reoperation. The longterm effect of SNM was evaluated in the group of the first 15 implanted patients from 20102011. Of these, 9 patients were available, in whom a new neurostimulator was reimplanted due to loss of battery power in 20182020. The mean length of follow-up was 112 months (99124). The mean number of FI episodes per week was 1.9 (013) after neurostimulator implantation compared to 13.6 (325) before implantation. The Cleveland Clinic Incontinence Score (CCIS) was 8.3 (316) after neurostimulator implantation compared to CCIS 18.8 (1520) before implantation. Both FI episode counts and CCIS scores were significantly lower (p.

Pelvic Floor Muscle Electromyography as a Guiding Tool During Lead Placement and (Re)Programming in Sacral Neuromodulation Patients: Validity, Reliability, and Feasibility of the Technique

To assess the validity, reliability, and feasibility of electromyography (EMG) as a tool to measure pelvic floor muscle (PFM) contractions during placement and (re)programming of the tined lead electrodes in sacral neuromodulation (SNM) patients. Single tertiary center, prospective study conducted between 2017 and 2019 consisting of three protocols including a total of 75 patients with overactive bladder (wet/dry) or nonobstructive urinary retention. PFM EMG was recorded using the multiple array probe (MAPLe), placed intravaginally. All stimulations (monophasic pulsed square wave, 210 μsec, 14 Hz) were performed using Medtronic's standard SNM stimulation equipment. During lead implantation, all four lead electrodes were stimulated with fixed increasing stimulation intensities (1-2-3-5-7-10 V). During lead electrode (re)programming, five bipolar lead electrode configurations were stimulated twice up to when an electrical PFM motor response (EPFMR), sensory response, and pain response were noted (i.e., the threshold), respectively. Additionally, amplitude and latency of the EPFMRs were determined. Validity, reliability, and feasibility were statistically analyzed using the intraclass correlation coefficient, weighted Cohen's kappa and linear regression, respectively. Validity: EPFMRs were strongly associated with visually detected PFM motor responses (κ = 0.90). Reliability: EPFMR amplitude (ICC = 0.99) and latency (ICC = 0.93) showed excellent repeatability. Feasibility: linear regression (EPFMR threshold = 0.18 mA + 0.76 * sensory response threshold) showed an increase in the sensory response threshold is associated with a smaller increase in EPFMR threshold, with the EPFMR occurring before or on the sensory response threshold in 83.8% of all stimulations. Measuring PFM contractions with EMG during placement and (re)programming of lead electrodes in SNM patients is valid, reliable, and feasible. Therefore, the use of PFM EMG motor responses could be considered as a tool to assist in these procedures.

A rare case of tined lead migration of InterStim device into the rectum with subsequent novel combined surgical-endoscopic removal technique.

After the introduction of self-anchoring tined leads in 2002, lead migration after sacral neuromodulation (SNM) in the form of InterStimTM (Medtronic, Minneapolis, MN) has been reduced; however, it remains a considerable complication of this otherwise low-risk procedure. As intestinal perforation through lead migration or primary incorrect positioning portrays a rarity and has been scarcely reported in the literature, no algorithm for explantation in such cases has been determined. We present a case of a young man with an SNM device implant (InterStim II®) because of neurogenic urinary retention, who was admitted with inflammation, localized at the sacral lead insertion site. Our diagnostic algorithm revealed a tined lead electrode protruding into the rectum without concomitant abscess. We performed an interdisciplinary surgical approach combining regular incisions over the sacrum and buttocks for dissection of the lead and the implanted pulse generator, respectively, with an endoscopic transanal lead extraction. This method prevented further bacterial seeding in the surrounding tissues of the colon and, therefore, presacral abscess formation or sacral osteomyelitis. Combined surgical-endoscopic removal of the InterStim device is an effective and safe procedure that should be included in the armamentarium of urologists performing neuromodulation surgery in cases of intestinal perforation.

Development of a CT-guided standard approach for tined lead implantation at the sacral nerve root S3 in minipigs for chronic neuromodulation.

PurposeThe aim of this study was to develop a controlled approach for sacral neuromodulation (SNM) to improve both nerve targeting and tined lead placement, for which a new computed tomography (CT)-guided implantation technique was analyzed in minipigs.Materials and methodsThis study included five female, adult Göttingen minipigs. In deep sedoanalgesia, the minipigs were placed in an extended prone position. Commercially available SNM materials were used (needle, introduction sheath, and quadripolar tined lead electrode). Gross anatomy was displayed by CT, and the nerves were bilaterally identified. The optimal angles to puncture the S3 foramen, the resulting access path, and the site for the skin incision were defined subsequently. The needle puncture and the tined lead placement were followed by successive CT scans/3D-reconstruction images. Once proper CT-guided placement of the needle and electrode was established, response to functional stimuli was intraoperatively checked to verify correct positioning.ResultsSuccessful bilateral tined lead implantation was performed in four out of five minipigs. Implantation was different from the clinical situation because the puncture was done from the contralateral side at a 30° angle to the midline and 60° horizontal angle to ensure both passage through the foramen and nerve access. Surgery time was 50–150 minutes. Stimulation response comprised a twitch of the perianal musculature and tail rotation to the contralateral side.ConclusionWe have established a new, minimally invasive, highly standardized, CT-guided SNM electrode implantation technique. Functional outcomes are clearly defined and reproducible. All procedures can be performed without complications. Future chronic stimulation studies in minipigs can thereby be conducted using a controlled and highly standardized protocol.

Number of active electrodes at time of staged tined lead interstim implant does not impact clinical outcomes.

To determine: (1) if obtaining motor response on <4 tined lead electrodes at time of placement affects subjective and objective clinical outcome and (2) voltage requirements to elicit motor response at implant and first postoperative visit number based on number of responding electrodes. We reviewed our prospective neuromodulation database to identify patients with unilateral S3 lead placement and motor response (bellows ± toe flexion) on stimulation of 1-4 electrodes, then grouped by number of active electrodes at lead placement. Stage 1 success, reoperation and reprogramming rates, mean voltage at implant and first postoperative visit, and Interstitial Cystitis Symptom/Problem Indices (ICSI-PI) were analyzed using Pearson's Chi-square, Fisher's exact, Kruskal-Wallis or Wilcoxon rank tests. Two hundred forty four patients met inclusion criteria, categorized into 1-2 (n = 25), 3 (n = 48), and 4 active electrodes (n = 171). There were no significant differences between groups in terms of age, indications for neuromodulation, or stage 1 success. At implant, patients with <4 active electrodes required higher mean voltages for motor responses (5.9, 4.9, and 3.9 volts for each group respectively; P < 0.0001). Mean voltages for sensory threshold at first postoperative programming were 1.5 ± 1.5, 0.9 ± 1.0, and 0.8 ± 1.0, respectively (P = 0.08). Overall reoperation rates, and reprogramming sessions at 24 months did not differ (P = 0.72 and P = 0.50). ICSI-PI scores improved similarly in all groups. Motor response on four electrodes is not necessary for successful stage 1 trial. Despite higher voltage requirements in those with <4 active electrodes at implant, this difference was not observed at initial postoperative programming. Neurourol. Urodynam. 35:625-629, 2016. © 2015 Wiley Periodicals, Inc.

MP89-11 CT-GUIDED SACRAL NEUROMODULATION S3 - A NEW TARGETED APPROACH AFTER INITIAL TREATMENT FAILURE: THE FIRST 10 PATIENTS

You have accessJournal of UrologyUrodynamics/Incontinence/Female Urology: Non-Neurogenic Voiding Dysfunction1 Apr 2015MP89-11 CT-GUIDED SACRAL NEUROMODULATION S3 - A NEW TARGETED APPROACH AFTER INITIAL TREATMENT FAILURE: THE FIRST 10 PATIENTS Sophina Trubel, Elena Esra Foditsch, Günter Janetschek, and Reinhold Posch-Zimmermann Sophina TrubelSophina Trubel More articles by this author , Elena Esra FoditschElena Esra Foditsch More articles by this author , Günter JanetschekGünter Janetschek More articles by this author , and Reinhold Posch-ZimmermannReinhold Posch-Zimmermann More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1810AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Insertion of tined lead electrodes through the neuroforamen to the sacral root S3 under fluoroscopy is established for Sacral Neuromodulation (SNM). This approach is not feasible in some patients due to anatomic abnormalities. Our trial is to evaluate a Computed tomography (CT) - guided SNM procedure as a more targeted approach for electrode placement in patients who fail with the standard procedure. METHODS We included 10 patients (7 female, 3 male, mean age 47a). Indications for SNM were overactive bladder (3), retention (4), retention due to meningomyelocele (3). In 5 patients conventional puncture failed primarily, one patient was considered to be not accessible for conventional SNM due to trauma and in four patients an intraoperative positioning control was required due to electrode dislocation after initially successful SNM. The individual anatomy and the subsequent “roadmap” were figured out by an initial planning CT. CT- guided S3 approach itself was conducted in local anaesthesia by sequential scanning of the needle insertion. Once the nerve was reached according to CT criteria, the clinical response was evaluated. If an adequate stimulation result was confirmed, the electrodes were implanted again under CT guidance using the standard tools via guide wire. Further clinical evaluation was according to our standard protocol. RESULTS Bilateral S3 nerve root could be well identified by CT in all cases. CT-guided S3 access and an adequate clinical response could be obtained. The needed stimulation parameters were comparatively low. All patients were implanted bilaterally due to the specific clinical set up. Operation time was between 45 – 90 minutes. All but one patients underwent definitive IPG implantation after a successful clinical trial according to our standard criteria. No short/long term complications were observed. CONCLUSIONS CT-guided sacral neuromodulation (S3) offers a reliable and safe option for patients who are not suitable for or fail SNM under fluoroscopy due to anatomical complexity like menigomyelocele, narrow neuroforamina or following a trauma. The precise imaging might increase response rate and improve clinical effects. Long term SNM efficiacy might be increased by lower stimulation parameters needed after CT SNM. It might even be considered for patients with SNM failure after initial effectiveness. We will evaluate the stimulation parameters closely on the long run and evaluate more patients not suitable for the conventional SNM to prove this approach for new indications. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e1104 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sophina Trubel More articles by this author Elena Esra Foditsch More articles by this author Günter Janetschek More articles by this author Reinhold Posch-Zimmermann More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Laparoscopic placement of a tined lead electrode on the pudendal nerve with urodynamic monitoring of bladder function during electrical stimulation: an acute experimental study in healthy female pigs.

PurposeThe aim of this study was to develop a method for standard laparoscopic access to the pudendal nerve in pigs to implant an electrode for chronic neuromodulation studies.MethodsUsing routine laparoscopic surgical techniques, the pudendal nerve was located in 10 female pigs using standardized anatomical landmarks. A tined lead electrode was placed in parallel to the exposed pudendal nerve, and acute unilateral electrical stimulation was performed consecutively on both pudendal nerves. Bladder pressure and perineal skeletal muscle response was monitored during stimulation.ResultsStandard access to the pudendal nerve was successfully established in the pig model with surgical times of approximately 45 minutes for bilateral electrode placement. Acute unilateral stimulation did not evoke bladder responses but resulted in reliable stimulation-dependent activity of the perineal skeletal muscles. The structural integrity of the pudendal nerves was confirmed in all cases.ConclusionsThese results illustrate the effectiveness of laparoscopy for standardised, safe nerve localisation and electrode implantation at the pudendal nerve in pigs. Laparoscopic implantation represents an alternative approach for performing electrode implantation under optical guidance versus the standard approach of percutaneous, neuro-physiological monitored implantation. In the future, pudendal neuromodulation may be used as a supplement to sacral neuromodulation or as a standalone therapeutic approach, depending on the underlying bladder dysfunction.

Sacral nerve stimulation lead implantation using the o-arm

BackgroundSacral neuromodulation operations have usually been performed based on 2D fluoro images. However, sacral nerve stimulation lead implantation may be challenging when the normal anatomy is confused by obesity or congenital anomalies. Thus the surgical navigation and intraoperative imaging methods could be helpful as those same methods have proven to be feasible methods for guiding other surgical operations. Our recent knowledge about the O-arm in trauma pelvic operations encouraged us to evaluate the usefulness of O-arm guided navigation in sacral neuromodulation. Similar navigation would be useful for complex sacral nerve stimulation lead implantations.MethodsIn this preliminary article we report our experience of utilizing the orthopedically optimized O-arm to implant the S3 stimulation electrode in a patient. The 3D O-arm imaging was performed intraoperatively under surgical navigation control. General anesthesia was used. The obtained 3D image dataset was registered automatically into the patient’s anatomy. The stimulation needle was guided and the tined lead electrode was implanted using navigation.ResultsThe bony sacral structures were clearly visualized. Due to automatic registration, the navigation was practicable instantly after the O-arm scanning and operation could be performed successfully under navigation control.ConclusionsTo our knowledge, this is the first published tined lead implantation which was guided based on the surgical navigation and intraoperative O-arm images. In this case, the applied method was useful and helped the surgeon to demarcate the region of surgical interest. The method is slightly more invasive than the formal technique but could be an option in anatomically challenging cases and reoperations. However, further evaluation with larger patient series is required before definitive recommendations can be made.

Sakrale Neuromodulation in der Urologie – Entwicklung und aktueller Stand

Sacral neuromodulation (SNM) in urology is employed to treat refractory lower urinary tract dysfunction as well as chronic pelvic pain. Electrical stimulation of the sacral afferents (S2 - S4) causes activation and conditioning of higher autonomic and somatic neural structures and thereby influences the efferents controlling the urinary bladder, the rectum and their related sphincter systems. It is therefore possible to treat overactivity as well as hypocontractility and functional bladder neck obstruction. SNM treatment is conducted biphasically. Initially, test electrodes are placed to evaluate changes in micturition and pain parameters. If, in this first phase - called peripheral nerve evaluation (PNE test) - sufficient improvements are observed, the patient progresses to phase two which involves implantation of the permanent electrodes and impulse generator system. In recent years, the "two stage approach" with initial implantation of the permanent electrodes has been favoured as it increases treatment success rates. Long-term success rates of SNM vary significantly in the literature (50 - 80 %) due to heterogeneous patient populations as well as improved surgical approaches. With the introduction of "tined lead electrodes" (2002), tissue damage is reduced to a minimum. Technical innovation, financial feasibility (reimbursed in Germany since 2004) and wider application, especially in otherwise therapy-refractory patients or complex dysfunctions of the pelvis, have established SNM as a potent treatment option in urology.

Factors affecting the outcome of temporary sacral nerve stimulation for faecal incontinence. The value of the new tined lead electrode

Sacral nerve stimulation (SNS) is an effective but expensive treatment for faecal incontinence. About 50% of the patients are unresponsive for unknown reasons, hence knowledge of any factors predictive of success would be highly desirable. The aim of this study was to analyse the potential factors associated with a successful outcome of the temporary test of electrostimulation. Eighty-five patients with faecal incontinence were tested for SNS. The cause was idiopathic in 45, iatrogenic or obstetric in 28, spinal lesion or neurological diseases in nine and anal malformation in three patients; 43 were tested with a unipolar electrode and 42 with a quadripolar electrode. The severity of faecal incontinence was evaluated using the American Medical System (AMS) score and Wexner's score. A positive response was obtained in 45 patients (53%); 40 (47%) were implanted with a permanent pulse generator. Responders and nonresponders were comparable in age, duration of incontinence, anal manometry, pudendal nerve terminal motor latency and diabetes. Unipolar electrode test (PNE test) was able to elicit positive responses in 18 of 43 (42%) and the quadripolar in 27 of 42 patients (P < 0.001). Type of incontinence and gender did not affect the success rate. Patients with idiopathic incontinence had a significantly higher response rate (P =0.022). Multivariate regression analysis indicated use of a quadripolar electrode as the only independent variable predicting the success of SNS (OR = 5.58, P = 0.009). Use of the quadripolar electrode is the only factor significantly related to the success of SNS.

Cost-Effectiveness of Sacral Neuromodulation Versus Intravesical Botulinum A Toxin for Treatment of Refractory Urge Incontinence

We determined the cost-effectiveness of sacral neuromodulation vs intravesical botulinum toxin A for the treatment of refractory urge incontinence. We developed a Markov decision model using a societal perspective to compare costs (2008 U.S. dollars) and effectiveness (quality adjusted life-years) of sacral nerve stimulation and botulinum toxin A. Our primary outcome was the incremental cost-effectiveness ratio, which was defined as (sacral nerve stimulation cost - botulinum toxin A cost)/(sacral nerve stimulation quality adjusted life-year - botulinum toxin A quality adjusted life-year). Sensitivity analyses were performed to assess the impact of varying efficacy, costs and adverse event rates over the range of reported values. In the base case scenario sacral nerve stimulation was more expensive ($15,743 vs $4,392) and more effective (1.73 vs 1.63 quality adjusted life-years) than botulinum toxin A during a 2-year period. The incremental cost-effectiveness ratio was $116,427 per quality adjusted life-year. Using conventional incremental cost-effectiveness ratio thresholds of $50,000 and $100,000 per quality adjusted life-year, sacral nerve stimulation was not cost-effective. In sensitivity analyses intravesical botulinum generally remained cost-effective. During a 2-year period botulinum toxin A was cost-effective compared to sacral neuromodulation for the treatment of refractory urge incontinence. Additional data regarding time to failure after botulinum toxin A injections, long-term efficacy with repeat botulinum toxin A injections and long-term complications with both therapies will be helpful for future cost-effectiveness studies.

Failure of Sacral Nerve Stimulation Due to Migration of Tined Lead

Stimulation of the sacral nerves is a commonly used treatment for frequency, urgency, urge incontinence, retention and other types of voiding dysfunction. Minimally invasive placement of a percutaneous permanent quadripolar tined lead into the sacral foramen has been described. No lead migration has been reported. We report on our experience with lead migration and the subsequent failure of InterStim in a large cohort of patients with a focus on possible diagnostic and salvage techniques. Between February 2002 and April 2005 tined lead electrodes were implanted in the S3 foramen in 235 patients using the InterStim system. Patients with a good response during the testing phase (greater than 50% improvement) underwent placement of an implantable pulse generator. Position was confirmed by radiographic evaluation intraoperatively. Sacral radiographs were obtained at the first postoperative visit, after IPG placement and whenever there was a change in symptomatic response. There were 5 patients (2.1%) in whom treatment failed after a successful trial of stimulation due to lead migration. This was seen as early as 3 weeks and as late as 8 months. Migration of the lead occurred between first and second stage implantation in 1 of the 5 cases, and occurred after the second stage in 4 of 5. Anterior migration was noted in 4 patients and posterior migration was noted in 1. Lead migration after placement of the tined lead can occur and thus sacral radiographs should be routinely used. This complication can be easily resolved without significant morbidity to the patient.

New Tined Lead Electrode in Sacral Neuromodulation: Experience from a Multicentre European Study

New Tined Lead Electrode in Sacral Neuromodulation: Experience from a Multicentre European Study

New tined lead electrode in sacral neuromodulation: experience from a multicentre European study

The use of a new tined lead electrode for sacral neuromodulation (SNS) was evaluated in a European study including 127 patients with chronic voiding dysfunction. The tined lead can be implanted during the first stage of the SNS procedure, which makes a longer test period possible before implanting the pulse generator in a second stage. Implantation of the tined lead was performed under local anaesthesia in 89% of patients. Screening lasted on average 30 days. Screening with the tined lead was considered successful by the physicians in 77% of patients (n=72). In 74% of first stage patients (n=70), at least 50% improvement in the main symptoms versus baseline was obtained. This was sustained for up to 6 weeks. All of these patients received the pulse generator in a second stage. The outcome of this study supports the use of the tined lead electrode as a screening tool in SNS therapy.

New screening technique for sacral nerve stimulation under local anaesthesia

The purpose of this study was to assess the influence of the type of anaesthesia (local vs. general) and of the electrode used (test electrode vs. tined lead) on a successful screening period. Between May 2001 and January 2004, we performed 25 percutaneous nerve evaluation (PNE) tests in 20 patients (11 women). The first 15 PNE tests were followed by introducing a conventional electrode, and since 2003 by a tined lead electrode. Success was defined as reduction of symptoms by more than 50%. A stimulator was implanted in 13 (68%) patients, including 4 of 14 screened with the conventional electrode and 9 of 10 screened with tined lead electrode (p=0.005). Eleven (44%) of the PNE tests were done under local anaesthesia, but the success rate was not influenced by the type of anaesthesia (local 46% vs. general 61%, p=0.682). PNE testing and implantation of the tined lead electrode can be easily performed at the same time under local anaesthesia. The use of the new tined lead electrode significantly increased the success rate for the screening phase.