{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T18:47:37Z","timestamp":1792176457212,"version":"4.4.0"},"reference-count":32,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2020,5,22]],"date-time":"2020-05-22T00:00:00Z","timestamp":1590105600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2020,5,22]],"date-time":"2020-05-22T00:00:00Z","timestamp":1590105600000},"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":["Radiat Oncol"],"published-print":{"date-parts":[[2020,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n<jats:title>Background<\/jats:title>\n<jats:p>Stereotactic radiosurgery (SRS) is an effective treatment for trigeminal neuralgia (TN). Nevertheless, a proportion of patients will experience recurrence and treatment-related sensory disturbances. In order to evaluate the predictors of efficacy and safety of image-guided non-isocentric radiosurgery, we analyzed the impact of trigeminal nerve volume and the nerve dose\/volume relationship, together with relevant clinical characteristics.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Methods<\/jats:title>\n<jats:p>Two-hundred and ninety-six procedures were performed on 262 patients at three centers. In 17 patients the TN was secondary to multiple sclerosis (MS). Trigeminal pain and sensory disturbances were classified according to the Barrow Neurological Institute (BNI) scale. Pain-free-intervals were investigated using Kaplan Meier analyses. Univariate and multivariate Cox regression analyses were performed to identify predictors.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Results<\/jats:title>\n<jats:p>The median follow-up period was 38\u2009months, median maximal dose 72.4\u2009Gy, median target nerve volume 25\u2009mm<jats:sup>3<\/jats:sup>, and median prescription dose 60\u2009Gy. Pain control rate (BNI I-III) at 6, 12, 24, 36, 48, and 60\u2009months were 96.8, 90.9, 84.2, 81.4, 74.2, and 71.2%, respectively. Overall, 18% of patients developed sensory disturbances. Patients with volume\u2009\u2265\u200930\u2009mm<jats:sup>3<\/jats:sup> were more likely to maintain pain relief (<jats:italic>p<\/jats:italic>\u2009=\u20090.031), and low integral dose (&lt;\u20091.4\u2009mJ) tended to be associated with more pain recurrence than intermediate (1.4\u20132.7\u2009mJ) or high integral dose (&gt;\u20092.7\u2009mJ; low vs. intermediate: log-rank test, \u03c7<jats:sup>2<\/jats:sup>\u2009=\u20095.02, <jats:italic>p<\/jats:italic>\u2009=\u20090.019; low vs. high: log-rank test, \u03c7<jats:sup>2<\/jats:sup>\u2009=\u20096.026, <jats:italic>p<\/jats:italic>\u2009=\u20090.014). MS, integral dose, and mean dose were the factors associated with pain recurrence, while re-irradiation and MS were predictors for sensory disturbance in the multivariate analysis.<\/jats:p>\n<\/jats:sec><jats:sec>\n<jats:title>Conclusions<\/jats:title>\n<jats:p>The dose to nerve volume ratio is predictive of pain recurrence in TN, and re-irradiation has a major impact on the development of sensory disturbances after non-isocentric SRS. Interestingly, the integral dose may differ significantly in treatments using apparently similar dose and volume constraints.<\/jats:p>\n<\/jats:sec>","DOI":"10.1186\/s13014-020-01535-1","type":"journal-article","created":{"date-parts":[[2020,5,22]],"date-time":"2020-05-22T11:02:56Z","timestamp":1590145376000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Factors affecting outcome in frameless non-isocentric stereotactic radiosurgery for trigeminal neuralgia: a multicentric cohort study"],"prefix":"10.1186","volume":"15","author":[{"given":"Alfredo","family":"Conti","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gueliz","family":"Acker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Pontoriero","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juliane","family":"Hardt","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne","family":"Kluge","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Cacciola","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Iat\u00ec","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Markus","family":"Kufeld","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Volker","family":"Budach","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Vajkoczy","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giancarlo","family":"Beltramo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefano","family":"Pergolizzi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Achille","family":"Bergantin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Franziska","family":"Loebel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvana","family":"Parisi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carolin","family":"Senger","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pantaleo","family":"Romanelli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2020,5,22]]},"reference":[{"key":"1535_CR1","doi-asserted-by":"publisher","first-page":"201","DOI":"10.1136\/bmj.39085.614792.BE","volume":"334","author":"L Bennetto","year":"2007","unstructured":"Bennetto L, Patel NK, Fuller G. Trigeminal neuralgia and its management. BMJ. 2007;334:201\u20135.","journal-title":"BMJ."},{"key":"1535_CR2","doi-asserted-by":"publisher","first-page":"677","DOI":"10.1097\/00006123-198605000-00028","volume":"18","author":"PJ Jannetta","year":"1986","unstructured":"Jannetta PJ. Trigeminal neuralgia. Neurosurgery. 1986;18:677.","journal-title":"Neurosurgery."},{"key":"1535_CR3","first-page":"331","volume":"44","author":"PJ Jannetta","year":"1997","unstructured":"Jannetta PJ. Outcome after microvascular decompression for typical trigeminal neuralgia, hemifacial spasm, tinnitus, disabling positional vertigo, and glossopharyngeal neuralgia (honored guest lecture). Clin Neurosurg. 1997;44:331\u201383.","journal-title":"Clin Neurosurg"},{"key":"1535_CR4","doi-asserted-by":"publisher","first-page":"818","DOI":"10.1016\/j.jocn.2014.11.028","volume":"22","author":"A Nanda","year":"2015","unstructured":"Nanda A, Javalkar V, Zhang S, Ahmed O. Long term efficacy and patient satisfaction of microvascular decompression and gamma knife radiosurgery for trigeminal neuralgia. J Clin Neurosci. 2015;22:818\u201322. https:\/\/doi.org\/10.1016\/j.jocn.2014.11.028.","journal-title":"J Clin Neurosci"},{"key":"1535_CR5","doi-asserted-by":"publisher","first-page":"26","DOI":"10.1016\/j.wneu.2016.06.097","volume":"94","author":"F Tomasello","year":"2016","unstructured":"Tomasello F, Esposito F, Abbritti RV, Angileri FF, Conti A, Cardali SM, et al. Microvascular decompression for trigeminal neuralgia: technical refinement for complication avoidance. World Neurosurg. 2016;94:26\u201331.","journal-title":"World Neurosurg"},{"issue":"S1","key":"1535_CR6","doi-asserted-by":"publisher","first-page":"153","DOI":"10.1007\/s10072-019-03814-6","volume":"40","author":"Marcello Marchetti","year":"2019","unstructured":"Marchetti M, Pinzi V, De Martin E, Ghielmetti F, Fariselli L. Radiosurgery for trigeminal neuralgia: the state of art. Neurol Sci. 2019. https:\/\/doi.org\/10.1007\/s10072-019-03814-6.","journal-title":"Neurological Sciences"},{"key":"1535_CR7","doi-asserted-by":"publisher","first-page":"1023","DOI":"10.1093\/neuros\/nyx571","volume":"83","author":"P Romanelli","year":"2018","unstructured":"Romanelli P, Conti A, Bianchi L, Bergantin A, Martinotti A, Beltramo G. Image-guided robotic radiosurgery for trigeminal neuralgia. Neurosurgery. 2018;83:1023\u201330.","journal-title":"Neurosurgery."},{"key":"1535_CR8","doi-asserted-by":"publisher","first-page":"733","DOI":"10.3171\/2017.9.JNS17545","volume":"130","author":"C Tuleasca","year":"2018","unstructured":"Tuleasca C, Regis J, Sahgal A, De Salles A, Hayashi M, Ma L, et al. Stereotactic radiosurgery for trigeminal neuralgia: a systematic review. J Neurosurg. 2018;130:733\u201357. https:\/\/doi.org\/10.3171\/2017.9.JNS17545.","journal-title":"J Neurosurg"},{"key":"1535_CR9","doi-asserted-by":"publisher","first-page":"758","DOI":"10.3171\/2009.7.JNS09694","volume":"112","author":"D Kondziolka","year":"2010","unstructured":"Kondziolka D, Zorro O, Lobato-Polo J, Kano H, Flannery TJ, Flickinger JC, et al. Gamma knife stereotactic radiosurgery for idiopathic trigeminal neuralgia. J Neurosurg. 2010;112:758\u201365.","journal-title":"J Neurosurg"},{"key":"1535_CR10","doi-asserted-by":"publisher","first-page":"566","DOI":"10.1227\/NEU.0b013e3182320d36","volume":"70","author":"K Marshall","year":"2012","unstructured":"Marshall K, Chan MD, McCoy TP, Aubuchon AC, Bourland JD, McMullen KP, et al. Predictive variables for the successful treatment of trigeminal neuralgia with gamma knife radiosurgery. Neurosurgery. 2012;70:566\u201372.","journal-title":"Neurosurgery."},{"key":"1535_CR11","doi-asserted-by":"publisher","first-page":"597","DOI":"10.3171\/jns.2004.100.4.0597","volume":"100","author":"N Massager","year":"2004","unstructured":"Massager N, Lorenzoni J, Devriendt D, Desmedt F, Brotchi J, Levivier M. Gamma knife surgery for idiopathic trigeminal neuralgia performed using a far-anterior cisternal target and a high dose of radiation. J Neurosurg. 2004;100:597\u2013605.","journal-title":"J Neurosurg"},{"key":"1535_CR12","doi-asserted-by":"publisher","first-page":"448","DOI":"10.1016\/j.wneu.2010.08.008","volume":"74","author":"BE Pollock","year":"2010","unstructured":"Pollock BE. Fitting radiosurgery into the trigeminal neuralgia management puzzle. World Neurosurg. 2010;74:448\u201350.","journal-title":"World Neurosurg"},{"key":"1535_CR13","doi-asserted-by":"publisher","first-page":"913","DOI":"10.3171\/jns.2006.104.6.913","volume":"104","author":"J Regis","year":"2006","unstructured":"Regis J, Metellus P, Hayashi M, Roussel P, Donnet A, Bille-Turc F. Prospective controlled trial of gamma knife surgery for essential trigeminal neuralgia. J Neurosurg. 2006;104:913\u201324.","journal-title":"J Neurosurg"},{"key":"1535_CR14","doi-asserted-by":"publisher","first-page":"766","DOI":"10.3171\/2009.8.JNS081706","volume":"112","author":"RI Riesenburger","year":"2010","unstructured":"Riesenburger RI, Hwang SW, Schirmer CM, Zerris V, Wu JK, Mahn K, et al. Outcomes following single-treatment gamma knife surgery for trigeminal neuralgia with a minimum 3-year follow-up. J Neurosurg. 2010;112:766\u201371.","journal-title":"J Neurosurg"},{"key":"1535_CR15","doi-asserted-by":"publisher","first-page":"434","DOI":"10.3171\/jns.2005.102.3.0434","volume":"102","author":"J Sheehan","year":"2005","unstructured":"Sheehan J, Pan H-C, Stroila M, Steiner L. Gamma knife surgery for trigeminal neuralgia: outcomes and prognostic factors. J Neurosurg. 2005;102:434\u201341.","journal-title":"J Neurosurg"},{"key":"1535_CR16","doi-asserted-by":"publisher","first-page":"442","DOI":"10.3171\/jns.2005.102.3.0442","volume":"102","author":"RG Tawk","year":"2005","unstructured":"Tawk RG, Duffy-Fronckowiak M, Scott BE, Alberico RA, Diaz AZ, Podgorsak MB, et al. Stereotactic gamma knife surgery for trigeminal neuralgia: detailed analysis of treatment response. J Neurosurg. 2005;102:442\u20139.","journal-title":"J Neurosurg"},{"key":"1535_CR17","doi-asserted-by":"publisher","first-page":"181","DOI":"10.3171\/2012.8.GKS121015","volume":"117","author":"C Tuleasca","year":"2012","unstructured":"Tuleasca C, Carron R, Resseguier N, Donnet A, Roussel P, Gaudart J, et al. Patterns of pain-free response in 497 cases of classic trigeminal neuralgia treated with gamma knife surgery and followed up for least 1 year. J Neurosurg. 2012;117:181\u20138. https:\/\/doi.org\/10.3171\/2012.8.GKS121015.","journal-title":"J Neurosurg"},{"key":"1535_CR18","doi-asserted-by":"publisher","first-page":"203","DOI":"10.1007\/s00701-011-1184-1","volume":"154","author":"A Conti","year":"2012","unstructured":"Conti A, Pontoriero A, Arpa D, Siragusa C, Tomasello C, Romanelli P, et al. Efficacy and toxicity of CyberKnife re-irradiation and \u201cdose dense\u201d temozolomide for recurrent gliomas. Acta Neurochir. 2012;154:203\u20139. https:\/\/doi.org\/10.1007\/s00701-011-1184-1.","journal-title":"Acta Neurochir"},{"key":"1535_CR19","doi-asserted-by":"publisher","DOI":"10.3171\/2013.2.FOCUS12414","volume":"34","author":"A Conti","year":"2013","unstructured":"Conti A, Pontoriero A, Ricciardi GK, Granata F, Vinci S, Angileri FF, et al. Integration of functional neuroimaging in CyberKnife radiosurgery: feasibility and dosimetric results. Neurosurg Focus. 2013;34:E5. https:\/\/doi.org\/10.3171\/2013.2.FOCUS12414.","journal-title":"Neurosurg Focus"},{"key":"1535_CR20","doi-asserted-by":"publisher","first-page":"A84","DOI":"10.1227\/01.NEU.0000341631.49154.62","volume":"64","author":"JRJ Adler","year":"2009","unstructured":"Adler JRJ, Bower R, Gupta G, Lim M, Efron A, Gibbs IC, et al. Nonisocentric radiosurgical rhizotomy for trigeminal neuralgia. Neurosurgery. 2009;64:A84\u201390.","journal-title":"Neurosurgery."},{"key":"1535_CR21","doi-asserted-by":"publisher","first-page":"A91","DOI":"10.1227\/01.NEU.0000340795.87734.70","volume":"64","author":"JD Borchers 3rd","year":"2009","unstructured":"Borchers JD 3rd, Yang HJ, Sakamoto GT, Howes GA, Gupta G, Chang SD, et al. Cyberknife stereotactic radiosurgical rhizotomy for trigeminal neuralgia: anatomic and morphological considerations. Neurosurgery. 2009;64:A91\u20135.","journal-title":"Neurosurgery."},{"key":"1535_CR22","doi-asserted-by":"publisher","first-page":"647","DOI":"10.1227\/01.neu.0000317313.46826.dc","volume":"62","author":"AT Villavicencio","year":"2008","unstructured":"Villavicencio AT, Lim M, Burneikiene S, Romanelli P, Adler JR, McNeely L, et al. Cyberknife radiosurgery for trigeminal neuralgia treatment: a preliminary multicenter experience. Neurosurgery. 2008;62:647\u201355.","journal-title":"Neurosurgery."},{"key":"1535_CR23","doi-asserted-by":"publisher","first-page":"452","DOI":"10.3171\/2016.10.JNS16747","volume":"128","author":"SH Mousavi","year":"2018","unstructured":"Mousavi SH, Niranjan A, Akpinar B, Monaco EA, Cohen J, Bhatnagar J, et al. A proposed plan for personalized radiosurgery in patients with trigeminal neuralgia. J Neurosurg. 2018;128:452\u20139. https:\/\/doi.org\/10.3171\/2016.10.JNS16747.","journal-title":"J Neurosurg"},{"key":"1535_CR24","doi-asserted-by":"publisher","first-page":"891","DOI":"10.3171\/2016.12.JNS161862","volume":"128","author":"A Wolf","year":"2018","unstructured":"Wolf A, Tyburczy A, Ye JC, Fatterpekar G, Silverman JS, Kondziolka D. The relationship of dose to nerve volume in predicting pain recurrence after stereotactic radiosurgery in trigeminal neuralgia. J Neurosurg. 2018;128:891\u20136. https:\/\/doi.org\/10.3171\/2016.12.JNS161862.","journal-title":"J Neurosurg"},{"key":"1535_CR25","doi-asserted-by":"publisher","first-page":"1013","DOI":"10.1016\/S0360-3016(00)00513-7","volume":"47","author":"CL Rogers","year":"2000","unstructured":"Rogers CL, Shetter AG, Fiedler JA, Smith KA, Han PP, Speiser BL. Gamma knife radiosurgery for trigeminal neuralgia: the initial experience of the Barrow neurological institute. Int J Radiat Oncol Biol Phys. 2000;47:1013\u20139.","journal-title":"Int J Radiat Oncol Biol Phys"},{"key":"1535_CR26","doi-asserted-by":"publisher","first-page":"1074","DOI":"10.1111\/tri.13463","volume":"32","author":"T Dziodzio","year":"2019","unstructured":"Dziodzio T, Jara M, Hardt J, Weiss S, Ritschl PV, Denecke C, et al. Effects of expanded allocation programmes and organ and recipient quality metrics on transplant-related costs in kidney transplantation - an institutional analysis. Transpl Int. 2019;32:1074\u201384. https:\/\/doi.org\/10.1111\/tri.13463.","journal-title":"Transpl Int"},{"key":"1535_CR27","doi-asserted-by":"publisher","first-page":"e6014","DOI":"10.7759\/cureus.6014","volume":"11","author":"P Romanelli","year":"2019","unstructured":"Romanelli P, Conti A, Redaelli I, Martinotti AS, Bergantin A, Bianchi LC, et al. Cyberknife radiosurgery for trigeminal neuralgia. Cureus. 2019;11:e6014. https:\/\/doi.org\/10.7759\/cureus.6014.","journal-title":"Cureus."},{"key":"1535_CR28","doi-asserted-by":"publisher","first-page":"1079","DOI":"10.3171\/2015.2.JNS142144","volume":"124","author":"J Regis","year":"2016","unstructured":"Regis J, Tuleasca C, Resseguier N, Carron R, Donnet A, Gaudart J, et al. Long-term safety and efficacy of gamma knife surgery in classical trigeminal neuralgia: a 497-patient historical cohort study. J Neurosurg. 2016;124:1079\u201387. https:\/\/doi.org\/10.3171\/2015.2.JNS142144.","journal-title":"J Neurosurg"},{"key":"1535_CR29","doi-asserted-by":"publisher","first-page":"105","DOI":"10.1159\/000075112","volume":"81","author":"P Romanelli","year":"2003","unstructured":"Romanelli P, Heit G, Chang SD, Martin D, Pham C, Adler J. Cyberknife radiosurgery for trigeminal neuralgia. Stereotact Funct Neurosurg. 2003;81:105\u20139.","journal-title":"Stereotact Funct Neurosurg"},{"key":"1535_CR30","doi-asserted-by":"publisher","first-page":"702","DOI":"10.1016\/j.wneu.2017.04.102","volume":"103","author":"A Conti","year":"2017","unstructured":"Conti A, Pontoriero A, Iati G, Esposito F, Siniscalchi EN, Crimi S, et al. Frameless stereotactic radiosurgery for treatment of multiple sclerosis-related trigeminal neuralgia. World Neurosurg. 2017;103:702\u201312.","journal-title":"World Neurosurg"},{"key":"1535_CR31","doi-asserted-by":"publisher","first-page":"225","DOI":"10.1016\/j.ijrobp.2010.05.058","volume":"81","author":"ZA Smith","year":"2011","unstructured":"Smith ZA, Gorgulho AA, Bezrukiy N, McArthur D, Agazaryan N, Selch MT, et al. Dedicated linear accelerator radiosurgery for trigeminal neuralgia: a single-center experience in 179 patients with varied dose prescriptions and treatment plans. Int J Radiat Oncol Biol Phys. 2011;81:225\u201331.","journal-title":"Int J Radiat Oncol Biol Phys"},{"key":"1535_CR32","doi-asserted-by":"publisher","first-page":"24","DOI":"10.1159\/000443529","volume":"94","author":"J Regis","year":"2016","unstructured":"Regis J, Tuleasca C, Resseguier N, Carron R, Donnet A, Yomo S, et al. The very long-term outcome of radiosurgery for classical trigeminal neuralgia. Stereotact Funct Neurosurg. 2016;94:24\u201332. https:\/\/doi.org\/10.1159\/000443529.","journal-title":"Stereotact Funct Neurosurg"}],"container-title":["Radiation Oncology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s13014-020-01535-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1186\/s13014-020-01535-1\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s13014-020-01535-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,5,21]],"date-time":"2021-05-21T23:11:05Z","timestamp":1621638665000},"score":1,"resource":{"primary":{"URL":"https:\/\/ro-journal.biomedcentral.com\/articles\/10.1186\/s13014-020-01535-1"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,5,22]]},"references-count":32,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2020,12]]}},"alternative-id":["1535"],"URL":"https:\/\/doi.org\/10.1186\/s13014-020-01535-1","relation":{},"ISSN":["1748-717X"],"issn-type":[{"value":"1748-717X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,5,22]]},"assertion":[{"value":"13 February 2020","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"13 April 2020","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"22 May 2020","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"The retrospective analysis was approved by the Ethics Committee Campus Charit\u00e9 Mitte (EA1\/233\/18) and by Comitato Ethico Interaziendale Messina (80\/19). Consent to participate is not applicable for a retrospective study.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"There is no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper. Dr. Conti and Dr. Romanelli received research and travel grants from Accuray Inc., Sunnyvale, CA, USA.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"115"}}