{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T04:04:56Z","timestamp":1789790696658,"version":"4.0.1"},"reference-count":10,"publisher":"Springer Science and Business Media LLC","issue":"5","license":[{"start":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T00:00:00Z","timestamp":1781740800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T00:00:00Z","timestamp":1781740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Vet Res Commun"],"published-print":{"date-parts":[[2026,10]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    Computational modelling of the electrical fields generated by helical electrodes surrounding the vagus nerve suggested a current of 1.0\u00a0mA should depolarise enough axons to give a therapeutic effect in epilepsy. An assumption that fibrous tissue formation would form between the electrodes and the nerve in implantable vagus nerve stimulators (VNS) led to the recommendation that 1.5\u00a0mA should be used to account for the increased impedance this would cause. This increase in impedance has not been documented, meaning that the higher current might not be necessary and could produce avoidable adverse effects such as coughing. To test the hypotheses that impedance does not always increase following VNS implantation and that more adverse effects might be seen with lower impedance circuits, circuit impedance was measured in dogs with implantable VNS at implantation and compared to impedance at 3\u20136 months post-implantation and at non-standardised time points thereafter. Dogs were grouped by severity of their coughing and the impedance between groups at 3\u20136 months was compared. Mean impedance at first implantation (2219\u2126, 95% CI 1894\u20132544) was no different from impedance at 3\u20136 months post implantation (2257\u2126, 95%CI 1944\u20132570,\n                    <jats:italic>p<\/jats:italic>\n                    \u2009=\u2009.80). Only 2 of 17 dogs showed a\u2009&gt;\u200950% increase in impedance (one at 3\u20136 and one at 7\u201312 months). Coughing severity was not influenced by impedance value despite similar stimulation currents. This work shows impedance does not consistently increase post implantation in dogs with VNS, suggesting that currents\u2009&gt;\u20091.0\u00a0mA might not be routinely needed to achieve a therapeutic effect.\n                  <\/jats:p>","DOI":"10.1007\/s11259-026-11362-6","type":"journal-article","created":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T03:29:43Z","timestamp":1781753383000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Impedance changes in chronic vagus nerve stimulator implantation in epileptic dogs"],"prefix":"10.1007","volume":"50","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5980-472X","authenticated-orcid":false,"given":"Thomas R.","family":"Harcourt-Brown","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,18]]},"reference":[{"key":"11362_CR1","doi-asserted-by":"publisher","unstructured":"Cukiert A, Cukiert C, Guimaraes RB et al (2023) Vagus nerve stimulation electrode impedance over time in children with lennox-gastaut syndrome. Neuromodulation. https:\/\/doi.org\/10.1016\/j.neurom.2023.06.006","DOI":"10.1016\/j.neurom.2023.06.006"},{"key":"11362_CR3","doi-asserted-by":"publisher","first-page":"1017","DOI":"10.1046\/j.1528-1157.2001.0420081017.x","volume":"42","author":"CM DeGiorgio","year":"2001","unstructured":"DeGiorgio CM, Thompson J, Lewis P et al (2001) Vagus nerve stimulation: analysis of device parameters in 154 patients during the long-term XE5 study. Epilepsia 42:1017\u20131020. https:\/\/doi.org\/10.1046\/j.1528-1157.2001.0420081017.x","journal-title":"Epilepsia"},{"key":"11362_CR2","doi-asserted-by":"publisher","first-page":"317","DOI":"10.1212\/01.wnl.0000168899.11598.00","volume":"65","author":"C DeGiorgio","year":"2005","unstructured":"DeGiorgio C, Heck C, Bunch S et al (2005) Vagus nerve stimulation for epilepsy: randomized comparison of three stimulation paradigms. Neurology 65:317\u2013319. https:\/\/doi.org\/10.1212\/01.wnl.0000168899.11598.00","journal-title":"Neurology"},{"key":"11362_CR4","doi-asserted-by":"publisher","first-page":"23","DOI":"10.1007\/BF02368219","volume":"22","author":"WM Grill","year":"1994","unstructured":"Grill WM, Mortimer JT (1994) Electrical properties of implant encapsulation tissue. Ann Biomed Eng 22:23\u201333. https:\/\/doi.org\/10.1007\/BF02368219","journal-title":"Ann Biomed Eng"},{"key":"11362_CR5","doi-asserted-by":"publisher","first-page":"2350","DOI":"10.1111\/jvim.16226","volume":"35","author":"TR Harcourt-Brown","year":"2021","unstructured":"Harcourt-Brown TR, Carter M (2021) Implantable vagus nerve stimulator settings and short-term adverse effects in epileptic dogs. J Vet Intern Med 35:2350\u20132358. https:\/\/doi.org\/10.1111\/jvim.16226","journal-title":"J Vet Intern Med"},{"key":"11362_CR6","doi-asserted-by":"publisher","first-page":"S31","DOI":"10.1212\/wnl.59.6_suppl_4.s31","volume":"59","author":"C Heck","year":"2002","unstructured":"Heck C, Helmers SL, DeGiorgio CM (2002) Vagus nerve stimulation therapy, epilepsy, and device parameters: scientific basis and recommendations for use. Neurology 59:S31\u2013S37. https:\/\/doi.org\/10.1212\/wnl.59.6_suppl_4.s31","journal-title":"Neurology"},{"key":"11362_CR7","doi-asserted-by":"publisher","first-page":"336","DOI":"10.1111\/j.1600-0404.2012.01656.x","volume":"126","author":"SL Helmers","year":"2012","unstructured":"Helmers SL, Begnaud J, Cowley A et al (2012) Application of a computational model of vagus nerve stimulation. Acta Neurol Scand 126:336\u2013343. https:\/\/doi.org\/10.1111\/j.1600-0404.2012.01656.x","journal-title":"Acta Neurol Scand"},{"key":"11362_CR8","doi-asserted-by":"publisher","first-page":"705","DOI":"10.1111\/aor.14500","volume":"47","author":"MR Horn","year":"2023","unstructured":"Horn MR, Vetter C, Bashirullah R et al (2023) Characterization of the electrical properties of mammalian peripheral nerve laminae. Artif Organs 47:705\u2013720. https:\/\/doi.org\/10.1111\/aor.14500","journal-title":"Artif Organs"},{"key":"11362_CR9","doi-asserted-by":"publisher","first-page":"71","DOI":"10.1111\/vsu.12427","volume":"45","author":"V Martl\u00e9","year":"2016","unstructured":"Martl\u00e9 V, Van Ham LML, Boon P et al (2016) Vagus Nerve Stimulator Placement in Dogs: Surgical Implantation Technique, Complications, Long-Term Follow-Up, and Practical Considerations. Vet Surg 45:71\u201378. https:\/\/doi.org\/10.1111\/vsu.12427","journal-title":"Vet Surg"},{"key":"11362_CR10","doi-asserted-by":"publisher","first-page":"977","DOI":"10.2460\/javma.2002.221.977","volume":"221","author":"KR Mu\u00f1ana","year":"2002","unstructured":"Mu\u00f1ana KR, Vitek SM, Tarver WB et al (2002) Use of vagal nerve stimulation as a treatment for refractory epilepsy in dogs. J Am Vet Med Assoc 221:977\u2013983. https:\/\/doi.org\/10.2460\/javma.2002.221.977","journal-title":"J Am Vet Med Assoc"}],"container-title":["Veterinary Research Communications"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s11259-026-11362-6.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s11259-026-11362-6","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s11259-026-11362-6.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T03:55:01Z","timestamp":1789790101000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s11259-026-11362-6"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,18]]},"references-count":10,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2026,10]]}},"alternative-id":["11362"],"URL":"https:\/\/doi.org\/10.1007\/s11259-026-11362-6","relation":{"has-preprint":[{"id-type":"doi","id":"10.21203\/rs.3.rs-9780401\/v1","asserted-by":"object"}]},"ISSN":["0165-7380","1573-7446"],"issn-type":[{"value":"0165-7380","type":"print"},{"value":"1573-7446","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,18]]},"assertion":[{"value":"21 May 2026","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"14 June 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"18 June 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"This study was conducted with institutional ethical approval from the University of Bristol Animal Services Unit (VIN-24-021).","order":1,"name":"Ethics","label":"Statement of animal ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"THB is a scientific advisor to Auxilium who manufacture a canine-specific VNS system.","order":2,"name":"Ethics","label":"Competing interests","group":{"name":"EthicsHeading","label":"Declarations"}}],"article-number":"403"}}