{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T18:48:26Z","timestamp":1792176506022,"version":"4.4.0"},"reference-count":18,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2025,4,30]],"date-time":"2025-04-30T00:00:00Z","timestamp":1745971200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,4,30]],"date-time":"2025-04-30T00:00:00Z","timestamp":1745971200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100005366","name":"University of Oslo","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100005366","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Acta Neurochir"],"abstract":"<jats:title>Abstract<\/jats:title>\n          <jats:sec>\n            <jats:title>Purpose<\/jats:title>\n            <jats:p>Percutaneous transoval glycerol injection (GI) has been widely used since 1981 in the treatment of patients with trigeminal neuralgia. However, outcomes have been more variable than with other percutaneous treatments. Although most authors state that they use H\u00e4rtel\u2019s technique, the variations are numerous\u2014which may explain procedural problems and most of the poor results. The aim of the present imaging-based study, therefore, was to revisit H\u00e4rtel\u2019s technique and identify optimal landmarks for guiding the needle from the cheek to Meckel\u2019s cave.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Methods<\/jats:title>\n            <jats:p>Eleven patients referred for trigeminal neuralgia were studied. We used CT- and MRI-based simulations to determine the optimal entry points in the cheek and trajectories through foramen ovale (FO) to reach Meckel\u2019s cave \u2013 and compared our findings with the results from H\u00e4rtel\u2019s original study.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Results<\/jats:title>\n            <jats:p>The optimal entry point was located at 2 mm below the horizontal plane through the angle of the mouth and just in front of the anterior edge of the mandibular ramus. From this entry point\u2014situated around 10 mm below H\u00e4rtel\u2019s preferred entry point\u2014Meckel\u2019s cave was easily accessible through the medial part of FO in 17 of 22 sides.<\/jats:p>\n          <\/jats:sec>\n          <jats:sec>\n            <jats:title>Conclusion<\/jats:title>\n            <jats:p>The findings from this study suggest that the technical results of transoval glycerol injection can be improved if we 1. Select the optimal entry point, 2. Guide the needle under fluoroscopy through the medial part of the foramen ovale, and 3. Minimize movement of the soft tissues in the cheek.<\/jats:p>\n          <\/jats:sec>","DOI":"10.1007\/s00701-025-06526-3","type":"journal-article","created":{"date-parts":[[2025,4,30]],"date-time":"2025-04-30T06:13:21Z","timestamp":1745993601000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Revisiting H\u00e4rtel\u2019s technique for percutaneous transoval glycerol injection"],"prefix":"10.1007","volume":"167","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1986-2669","authenticated-orcid":false,"given":"Haldor","family":"Sletteb\u00f8","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5954-7586","authenticated-orcid":false,"given":"Tomas","family":"Sakinis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,4,30]]},"reference":[{"key":"6526_CR1","doi-asserted-by":"publisher","first-page":"168","DOI":"10.1159\/000070830","volume":"79","author":"PC Blomstedt","year":"2002","unstructured":"Blomstedt PC, Bergenheim AT (2002) Technical difficulties and perioperative complications of retrogasserian glycerol rhizotomy for trigeminal neuralgia. Stereot Funct Neuros 79:168\u2013181. https:\/\/doi.org\/10.1159\/000070830","journal-title":"Stereot Funct Neuros"},{"key":"6526_CR2","doi-asserted-by":"publisher","first-page":"622","DOI":"10.3340\/jkns.2022.0074","volume":"65","author":"KW Chang","year":"2022","unstructured":"Chang KW, Jung HH, Chang JW (2022) Percutaneous procedures for trigeminal neuralgia. J Korean Neurosurg Soc 65:622\u2013632","journal-title":"J Korean Neurosurg Soc"},{"key":"6526_CR3","doi-asserted-by":"publisher","first-page":"1414","DOI":"10.3171\/2019.1.JNS18899","volume":"132","author":"A Elnashar","year":"2020","unstructured":"Elnashar A, Patel SK, Kurbanov A, Zvereva K, Keller JT, Grande AW (2020) Comprehensive anatomy of the foramen ovale critical to percutaneous stereotactic radiofrequency rhizotomy: cadaveric study of dry skulls. 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Given the retrospective design of this study and the use of non-identifiable images, informed consent was not necessary for the other patients involved.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent to participate"}},{"value":"The authors declare no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"126"}}