{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T11:07:52Z","timestamp":1779361672175,"version":"3.51.4"},"reference-count":28,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"18","license":[{"start":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T00:00:00Z","timestamp":1777852800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Neurosurg Case Lessons"],"published-print":{"date-parts":[[2026,5,4]]},"abstract":"\n BACKGROUND<\/jats:title>\n The craniovertebral junction contains critical structures such as the medulla oblongata, upper cervical spinal cord, and vertebral arteries; therefore, selecting the surgical approach is particularly important given its anatomical complexity. Various anterior approaches have been proposed for this purpose. However, in recent years, endoscopic endonasal decompression has increasingly replaced the traditional transoral approach for the treatment of upper anterior lesions.<\/jats:p>\n <\/jats:sec>\n \n OBSERVATIONS<\/jats:title>\n The authors encountered a case of ventral medullary compression caused by an inferior clival osteophyte that progressively enlarged after C1\u20132 fixation. The endoscopic endonasal approach (EEA), which provides the shortest and most direct route to the lesion, was selected for this study. Intraoperative use of the O-arm enabled precise real-time assessment of the extent of bone removal, thereby enabling complete decompression. Mechanical loading following C1\u20132 fixation is considered a possible contributing factor to osteophyte enlargement.<\/jats:p>\n <\/jats:sec>\n \n LESSONS<\/jats:title>\n Although neuronavigation is commonly used in the EEA, its reliance on preoperative imaging limits its ability to accurately assess decompression. The O-arm, which provides real-time intraoperative imaging, has proven extremely useful in overcoming this limitation.<\/jats:p>\n \n https:\/\/thejns.org\/doi\/10.3171\/CASE251039<\/jats:ext-link>\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3171\/case251039","type":"journal-article","created":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T16:15:34Z","timestamp":1778516134000},"source":"Crossref","is-referenced-by-count":0,"title":["O-arm\u2013assisted endoscopic endonasal decompression for medullary compression caused by a clival osteophyte: illustrative case"],"prefix":"10.3171","volume":"11","author":[{"given":"Yusuke","family":"Muramatsu","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Nagoya University Graduate School of Medicine, Nagoya, Aichi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kazuhito","family":"Takeuchi","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Nagoya University Graduate School of Medicine, Nagoya, Aichi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2162-2100","authenticated-orcid":true,"given":"Motonori","family":"Ishii","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Inazawa Municipal Hospital, Inazawa, Aichi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1675-319X","authenticated-orcid":true,"given":"Sho","family":"Akahori","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Inazawa Municipal Hospital, Inazawa, Aichi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8497-2373","authenticated-orcid":true,"given":"Yu","family":"Yamamoto","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Aichi Medical University, Nagakute, Aichi, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2484-1360","authenticated-orcid":true,"given":"Ryuta","family":"Saito","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Nagoya University Graduate School of Medicine, Nagoya, Aichi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masakazu","family":"Takayasu","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Inazawa Municipal Hospital, Inazawa, Aichi"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1754","reference":[{"issue":"4","key":"bib1","series-title":"Neurosurg Focus","first-page":"E8","article-title":"Evolution of transoral approaches, endoscopic endonasal approaches, and reduction strategies for treatment of craniovertebral junction pathology: a treatment algorithm update","volume":"38","author":"Dlouhy","year":"2015","unstructured":"Dlouhy BJDahdaleh NSMenezes AH.Evolution of transoral approaches, endoscopic endonasal approaches, and reduction strategies for treatment of craniovertebral junction pathology: a treatment algorithm update. 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