{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T02:34:15Z","timestamp":1789094055558,"version":"build-2803163510"},"reference-count":37,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T00:00:00Z","timestamp":1768348800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: Patients with deep brain stimulation (DBS) require regular follow-up. When a sudden loss of therapeutic effect occurs, impedance abnormalities are often the underlying cause. If reprogramming cannot restore clinical benefit, revision surgery may be necessary to replace defective hardware. Since all three major manufacturers are used at our center, we analyzed our patient cohort to determine the incidence and causes of impedance abnormalities. Methods: All 601 patients who underwent de novo DBS implantation in Hamm between 2009 and 2025 were evaluated for impedance abnormalities. In cases requiring revision surgery, the specific cause was identified. The manufacturer, electrodes, and contacts involved were systematically analyzed. Results: A total of 25 of 601 patients required revision surgery. Revision rates were 2.67% in patients with Parkinson\u2019s disease, 6.19% in those with a tremor, and 5.71% in those with dystonia. Across manufacturers, 7.6% of patients with a Medtronic system required revision surgery, compared with 3.4% of patients with an Abbott system and no patients with a Boston Scientific system. The primary causes of revision were electrode-related problems (19\/25), followed by extension defects (6\/25), connector issues (4\/25), and, in one case, a generator defect (1\/25). Conclusions: Only 4.16% of patients required revision surgery due to impedance abnormalities. Patients with a tremor and non-segmented electrodes showed a higher incidence than those with Parkinson\u2019s disease or dystonia. Predominantly older Medtronic systems had the highest revision rate, whereas no Boston Scientific systems required revision. In most cases, the electrodes were the primary source of impedance abnormalities. A total of 52% of revisions were performed within two years and 92% were performed within six years of implantation.<\/jats:p>","DOI":"10.3390\/jcm15020683","type":"journal-article","created":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T15:47:37Z","timestamp":1768405657000},"page":"683","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Impedance Problems and Their Causes\u2014A Single-Center Analysis of 601 Patients with De Novo Deep Brain Stimulation"],"prefix":"10.3390","volume":"15","author":[{"given":"Thomas","family":"Fortmann","sequence":"first","affiliation":[{"name":"Department of Stereotactic Neurosurgery, St. Barbara Hospital Hamm, 59073 Hamm, Germany"},{"name":"Faculty of Medicine, University of Witten\/Herdecke, 58455 Witten\/Herdecke, Germany"},{"name":"Department of Neurosurgery, St. Barbara Hospital Hamm, 59073 Hamm, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9592-3881","authenticated-orcid":false,"given":"Samer","family":"Zawy Alsofy","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Witten\/Herdecke, 58455 Witten\/Herdecke, Germany"},{"name":"Department of Neurosurgery, St. Barbara Hospital Hamm, 59073 Hamm, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4242-4197","authenticated-orcid":false,"given":"Antonio","family":"Santacroce","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Witten\/Herdecke, 58455 Witten\/Herdecke, Germany"},{"name":"Department of Neurosurgery, St. Barbara Hospital Hamm, 59073 Hamm, Germany"},{"name":"European Radiosurgery Center Munich, 81377 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Makoto","family":"Nakamura","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Witten\/Herdecke, 58455 Witten\/Herdecke, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Ewelt","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, St. Barbara Hospital Hamm, 59073 Hamm, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ralph","family":"Lehrke","sequence":"additional","affiliation":[{"name":"Department of Stereotactic Neurosurgery, St. Barbara Hospital Hamm, 59073 Hamm, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"131","DOI":"10.4103\/2152-7806.85473","article-title":"The importance of testing deep brain stimulation lead impedances before final lead implantation","volume":"2","author":"Nazzaro","year":"2011","journal-title":"Surg. Neurol. Int."},{"key":"ref_2","first-page":"e21518","article-title":"Elevated Electrode Impedances During Deep Brain Stimulation Surgery May Be Due to Peri-Electrode Air Collections","volume":"14","author":"Klassen","year":"2022","journal-title":"Cureus"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1111\/ner.12123","article-title":"Investigation of deep brain stimulation mechanisms during implantable pulse generator replacement surgery","volume":"17","author":"Swan","year":"2014","journal-title":"Neuromodulation"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"E264","DOI":"10.1093\/ons\/opz035","article-title":"Intraoperative High Impedance Levels During Placement of Deep Brain Stimulating Electrode","volume":"17","author":"Lyons","year":"2019","journal-title":"Oper. Neurosurg."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"542","DOI":"10.5334\/tohm.401","article-title":"Longitudinal Follow-up of Impedance Drift in Deep Brain Stimulation Cases","volume":"8","author":"Wong","year":"2018","journal-title":"Tremor Other Hyperkinetic Mov."},{"key":"ref_6","first-page":"e15539","article-title":"Characterizing Complications of Deep Brain Stimulation Devices for the Treatment of Parkinsonian Symptoms Without Tremor: A Federal MAUDE Database Analysis","volume":"13","author":"Bennett","year":"2021","journal-title":"Cureus"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Darie, L., Lumsdon, G., and Ellenbogen, J. (2025). Deep brain stimulation lead fracture with normal impedances: Case report and review of literature. Br. J. Neurosurg., 1\u20135.","DOI":"10.1080\/02688697.2025.2516813"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"765","DOI":"10.1016\/j.parkreldis.2012.03.014","article-title":"Hardware complications in deep brain stimulation: Electrode impedance and loss of clinical benefit","volume":"18","author":"Guridi","year":"2012","journal-title":"Park. Relat. Disord."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1799","DOI":"10.2147\/NDT.S86120","article-title":"Sudden loss of the deep brain stimulation effect with high impedance without macroscopic fracture: A case report and review of the published literature","volume":"11","author":"Yang","year":"2015","journal-title":"Neuropsychiatr. Dis. Treat."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1077","DOI":"10.1007\/s00701-020-04246-4","article-title":"DBS dysfunction mimicking transient ischemic attacks-a case report","volume":"162","author":"Allert","year":"2020","journal-title":"Acta Neurochir."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"467","DOI":"10.1016\/j.pjnns.2015.10.004","article-title":"Twiddler syndrome in a patient with tremor dominant Parkinson\u2019s disease. A case report and literature review","volume":"49","author":"Sobstyl","year":"2015","journal-title":"Neurol. Neurochir. Pol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"951","DOI":"10.1007\/s10143-021-01636-9","article-title":"A systematic review of Twiddler\u2019s syndrome: A hardware-related complication of deep brain stimulation","volume":"45","author":"Liu","year":"2022","journal-title":"Neurosurg. Rev."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"568","DOI":"10.1111\/ner.12785","article-title":"DBS Electrodes with Single Disconnected Contacts: Long-Term Observation and Implications for the Management","volume":"21","author":"Allert","year":"2018","journal-title":"Neuromodulation"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"562","DOI":"10.1111\/ner.12709","article-title":"Long-Term Stability of Short Circuits in Deep Brain Stimulation","volume":"21","author":"Allert","year":"2018","journal-title":"Neuromodulation"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1123","DOI":"10.1007\/s10143-021-01673-4","article-title":"Prevalence of distinct types of hardware failures related to deep brain stimulation","volume":"45","author":"Cabral","year":"2022","journal-title":"Neurosurg. Rev."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"625","DOI":"10.1080\/02688697.2021.1935727","article-title":"Complications associated with deep brain stimulation for Parkinson\u2019s disease: A MAUDE study","volume":"35","author":"Ward","year":"2021","journal-title":"Br. J. Neurosurg."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2343","DOI":"10.1007\/s00701-011-1187-y","article-title":"Electrode dysfunctions in patients with deep brain stimulation: A clinical retrospective study","volume":"153","author":"Allert","year":"2011","journal-title":"Acta Neurochir."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"955","DOI":"10.3171\/2012.8.JNS112073","article-title":"Short circuit in deep brain stimulation","volume":"117","author":"Samura","year":"2012","journal-title":"J. Neurosurg."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Sarica, C., Iorio-Morin, C., Aguirre-Padilla, D.H., Najjar, A., Paff, M., Fomenko, A., Yamamoto, K., Zemmar, A., Lipsman, N., and Ibrahim, G.M. (2021). Implantable Pulse Generators for Deep Brain Stimulation: Challenges, Complications, and Strategies for Practicality and Longevity. Front. Hum. Neurosci., 15.","DOI":"10.3389\/fnhum.2021.708481"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"108404","DOI":"10.1016\/j.clineuro.2024.108404","article-title":"PET imaging for a very early detection of rapid eye movement sleep behaviour disorder and Parkinson\u2019s disease\u2014A model-based cost-effectiveness analysis","volume":"243","author":"Fezeu","year":"2024","journal-title":"Clin. Neurol. Neurosurg."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1159\/000358014","article-title":"Variation in deep brain stimulation electrode impedance over years following electrode implantation","volume":"92","author":"Satzer","year":"2014","journal-title":"Stereotact. Funct. Neurosurg."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Satzer, D., Yu, H., Wells, M., Padmanaban, M., Burns, M.R., Warnke, P.C., and Xie, T. (2020). Deep Brain Stimulation Impedance Decreases Over Time Even When Stimulation Settings Are Held Constant. Front. Hum. Neurosci., 14.","DOI":"10.3389\/fnhum.2020.584005"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"746","DOI":"10.1016\/j.brs.2013.03.010","article-title":"Longitudinal impedance variability in patients with chronically implanted DBS devices","volume":"6","author":"Cheung","year":"2013","journal-title":"Brain Stimul."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1247","DOI":"10.1016\/j.parkreldis.2015.07.019","article-title":"Long-term evaluation of impedance levels and clinical development in subthalamic deep brain stimulation for Parkinson\u2019s disease","volume":"21","author":"Hartmann","year":"2015","journal-title":"Park. Relat. Disord."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"816","DOI":"10.1136\/jnnp-2013-306066","article-title":"Temporal macrodynamics and microdynamics of the postoperative impedance at the tissue-electrode interface in deep brain stimulation patients","volume":"85","author":"Lungu","year":"2014","journal-title":"J. Neurol. Neurosurg. Psychiatry"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Olson, J.W., Gonzalez, C.L., Brinkerhoff, S., Boolos, M., Wade, M.H., Hurt, C.P., Nakhmani, A., Guthrie, B.L., and Walker, H.C. (2022). Local anatomy, stimulation site, and time alter directional deep brain stimulation impedances. Front. Hum. Neurosci., 16.","DOI":"10.3389\/fnhum.2022.958703"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"447","DOI":"10.1016\/j.clinph.2005.10.007","article-title":"Sources and effects of electrode impedance during deep brain stimulation","volume":"117","author":"Butson","year":"2006","journal-title":"Clin. Neurophysiol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1093\/ons\/opaa326","article-title":"The Active Electrode in the Living Brain: The Response of the Brain Parenchyma to Chronically Implanted Deep Brain Stimulation Electrodes","volume":"20","author":"Evers","year":"2021","journal-title":"Oper. Neurosurg."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1159\/000090433","article-title":"Deep brain stimulation inactivity can produce unexpected high electrode impedances when reactivated, leading to a false conclusion of wire fracture","volume":"83","author":"Jaggi","year":"2005","journal-title":"Stereotact. Funct. Neurosurg."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3171\/CASE23349","article-title":"Impedance trend from a symptomatic perielectrode cystic cavity following deep brain stimulation: Illustrative case","volume":"6","author":"Elberson","year":"2023","journal-title":"J. Neurosurg. Case Lessons"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1733","DOI":"10.1016\/j.neurom.2022.04.047","article-title":"Impedance Characteristics of Stimulation Contacts in Deep Brain Stimulation of the Anterior Nucleus of the Thalamus and Its Relationship to Seizure Outcome in Patients with Refractory Epilepsy","volume":"26","author":"Peltola","year":"2023","journal-title":"Neuromodulation"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"493","DOI":"10.5334\/tohm.370","article-title":"Management of Elevated Therapeutic Impedances on Deep Brain Stimulation Leads","volume":"7","author":"Deeb","year":"2017","journal-title":"Tremor Other Hyperkinetic Mov."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Whitestone, J., Salih, A., and Goswami, T. (2023). Investigation of a Deep Brain Stimulator (DBS) System. Bioengineering, 10.","DOI":"10.3390\/bioengineering10101160"},{"key":"ref_34","first-page":"409356","article-title":"Lead Fractures in Deep Brain Stimulation during Long-Term Follow-Up","volume":"2010","year":"2010","journal-title":"Park. Dis."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"296","DOI":"10.1016\/j.neurom.2021.12.011","article-title":"Surgical and Hardware-Related Adverse Events of Deep Brain Stimulation: A Ten-Year Single-Center Experience","volume":"25","author":"Ackermans","year":"2022","journal-title":"Neuromodulation"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"108702","DOI":"10.1016\/j.clineuro.2024.108702","article-title":"Delayed postoperative impedance issues in patients treated with deep brain stimulation: A single-center retrospective study","volume":"249","author":"Sturgill","year":"2025","journal-title":"Clin. Neurol. Neurosurg."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"2485","DOI":"10.1007\/s00701-018-3658-x","article-title":"Unstable impedance of a single electrode contact resulting in loss of DBS therapy-a case report","volume":"160","author":"Allert","year":"2018","journal-title":"Acta Neurochir."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/2\/683\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T15:51:21Z","timestamp":1768405881000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/2\/683"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,14]]},"references-count":37,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,1]]}},"alternative-id":["jcm15020683"],"URL":"https:\/\/doi.org\/10.3390\/jcm15020683","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,14]]}}}