{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:08:29Z","timestamp":1760234909593,"version":"build-2065373602"},"reference-count":44,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,6,29]],"date-time":"2021-06-29T00:00:00Z","timestamp":1624924800000},"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>The increased awareness of discrepancies between self-reporting outcome measurements and objective outcome measurements within the field of neuromodulation has accelerated the search towards more objective measurements. The aim of this study was to evaluate whether an electronic nose can differentiate between chronic pain patients in whom Spinal Cord Stimulation (SCS) was activated versus deactivated. Twenty-seven patients with Failed Back Surgery Syndrome (FBSS) participated in this prospective pilot study. Volatile organic compounds in exhaled breath were measured with electronic nose technology (Aeonose\u2122) during SCS on and off states. Random forest was used with a leave-10%-out cross-validation method to determine accuracy of discriminating between SCS on and off states. Our random forest showed an accuracy of 0.56, with an area under the curve of 0.62, a sensitivity of 62% (95% CI: 41\u201379%) and a specificity of 50% (95% CI: 30\u201370%). Pain intensity scores were significantly different between both SCS states. Our findings indicate that we cannot discriminate between SCS off and on states based on exhaled breath with the Aeonose\u2122 in patients with FBSS. In clinical practice, these findings imply that with a noninvasive electronic nose, exhaled breath cannot be used as an additional marker of the effect of neuromodulation.<\/jats:p>","DOI":"10.3390\/jcm10132921","type":"journal-article","created":{"date-parts":[[2021,6,29]],"date-time":"2021-06-29T10:52:46Z","timestamp":1624963966000},"page":"2921","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Exhaled-Breath Testing Using an Electronic Nose during Spinal Cord Stimulation in Patients with Failed Back Surgery Syndrome: An Experimental Pilot Study"],"prefix":"10.3390","volume":"10","author":[{"given":"Lisa","family":"Goudman","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"},{"name":"STIMULUS Consortium (reSearch and TeachIng neuroModULation Uz bruSsel), Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"},{"name":"Center for Neurosciences (C4N), Vrije Universiteit Brussel, 1090 Brussels, Belgium"},{"name":"Pain in Motion International Research Group, 1090 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Julie","family":"Jansen","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"},{"name":"STIMULUS Consortium (reSearch and TeachIng neuroModULation Uz bruSsel), Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nieke","family":"Vets","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"},{"name":"STIMULUS Consortium (reSearch and TeachIng neuroModULation Uz bruSsel), Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ann","family":"De Smedt","sequence":"additional","affiliation":[{"name":"STIMULUS Consortium (reSearch and TeachIng neuroModULation Uz bruSsel), Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"},{"name":"Center for Neurosciences (C4N), Vrije Universiteit Brussel, 1090 Brussels, Belgium"},{"name":"Department of Physical Medicine and Rehabilitation, Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0577-5449","authenticated-orcid":false,"given":"Maarten","family":"Moens","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"},{"name":"STIMULUS Consortium (reSearch and TeachIng neuroModULation Uz bruSsel), Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"},{"name":"Center for Neurosciences (C4N), Vrije Universiteit Brussel, 1090 Brussels, Belgium"},{"name":"Pain in Motion International Research Group, 1090 Brussels, Belgium"},{"name":"Department of Radiology, Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"E33","DOI":"10.36076\/ppj\/2016.19.E33","article-title":"Effectiveness of Spinal Cord Stimulation in Chronic Spinal Pain: A Systematic Review","volume":"19","author":"Grider","year":"2016","journal-title":"Pain Physician"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1421","DOI":"10.1093\/pm\/pnz353","article-title":"A Systematic Literature Review of Spine Neurostimulation Therapies for the Treatment of Pain","volume":"21","author":"Deer","year":"2020","journal-title":"Pain Med."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Hofmeister, M., Memedovich, A., Brown, S., Saini, M., Dowsett, L.E., Lorenzetti, D.L., McCarron, T.L., MacKean, G., and Clement, F. 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