{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T15:53:21Z","timestamp":1793894001961,"version":"4.8.0"},"reference-count":20,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JNS"],"published-print":{"date-parts":[[2007,11]]},"abstract":"<jats:sec>\n<jats:title>Object<\/jats:title>\n<jats:p>In this study, the authors aimed to identify the factors that would predict the operative distance between the trigeminal nerve (fifth cranial nerve) and the acousticofacial nerve complex (seventh\u2013eighth cranial nerves) preoperatively when approaching the cerebellopontine angle (CPA) through the suboccipital retrosigmoid approach.<\/jats:p><\/jats:sec>\n<jats:sec>\n<jats:title>Methods<\/jats:title>\n<jats:p>In 40 consecutive patients who underwent microvascular decompression of the trigeminal nerve via a sub-occipital retrosigmoid approach for trigeminal neuralgia, the following three parameters were assessed on preoperative magnetic resonance images: 1) the angle between the tentorium and the line drawn from the hard palate (tentorial angle); 2) the angle between the lines drawn along the petrous bones ventral to the internal auditory canals (petrous angle); and 3) the angle between the tentorium and the line connecting the opisthion to the inion (occipital angle). The distance between the trigeminal nerve and the acousticofacial nerve complex (referred to as \u201cdistance\u201d) was measured intraoperatively. Statistical analysis was performed using the Pearson correlation test.<\/jats:p><\/jats:sec>\n<jats:sec>\n<jats:title>Results<\/jats:title>\n<jats:p>The mean values were 50.9 \u00b1 11.5\u00b0 for the tentorial angle, 102.5 \u00b1 13.1\u00b0 for the petrous angle, 83.4 \u00b1 9.7\u00b0 for the occipital angle, and 3.1 \u00b1 1.5 mm for distance. There was a strong inverse correlation between the tentorial angle and distance (r = \u22120.228, p = 0.08). The mean distance was 3.5 \u00b1 1.9 mm for a tentorial angle less than 51\u00b0 and 2.7 \u00b1 1.1 mm for a tentorial angle of at least 51\u00b0. No correlation existed between either the petrous or occipital angles and distance.<\/jats:p><\/jats:sec>\n<jats:sec>\n<jats:title>Conclusions<\/jats:title>\n<jats:p>The distance between the trigeminal nerve and acousticofacial nerve complex decreases in the presence of a steep tentorial angle. This limits the operating field between these cranial nerves when reaching the petroclival or the superior CPA regions through the retrosigmoid approach. Awareness of such anatomical features at the time of pre-operative planning is of paramount importance in selecting the optimum surgical approach and minimizing operative complications.<\/jats:p><\/jats:sec>","DOI":"10.3171\/jns-07\/11\/0932","type":"journal-article","created":{"date-parts":[[2007,12,13]],"date-time":"2007-12-13T18:48:13Z","timestamp":1197571693000},"page":"932-936","source":"Crossref","is-referenced-by-count":13,"title":["Significance of the tentorial alignment in approaching the trigeminal nerve and the ventral petrous region through the suboccipital retrosigmoid technique"],"prefix":"10.3171","volume":"107","author":[{"given":"Burak","family":"Sade","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joung H.","family":"Lee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"key":"b1-1070932","series-title":"Neurosurgery","doi-asserted-by":"publisher","first-page":"813","DOI":"10.1227\/00006123-199211000-00001","article-title":"Microsurgical removal of petroclival meningiomas: a report of 33 patients","volume":"31","author":"Bricolo","year":"1992"},{"key":"b2-1070932","series-title":"J Neurosurg","doi-asserted-by":"publisher","first-page":"20","DOI":"10.3171\/jns.1996.84.1.0020","article-title":"Petro-clival meningiomas: surgical experience in 109 cases","volume":"84","author":"Couldwell","year":"1996"},{"issue":"2","key":"b3-1070932","series-title":"Neurosurg Focus","first-page":"E7","article-title":"Surgical management of petroclival meningiomas: factors determining the choice of approach","volume":"19","author":"Erkmen","year":"2005"},{"key":"b4-1070932","series-title":"Surg Neurol","doi-asserted-by":"publisher","first-page":"332","DOI":"10.1016\/j.surneu.2003.12.008","article-title":"Conventional posterior fossa approach for surgery on petroclival meningiomas: a report on an experience with 28 cases","volume":"62","author":"Goel","year":"2004"},{"key":"b5-1070932","series-title":"Neurosurgery","doi-asserted-by":"publisher","first-page":"1436","DOI":"10.1227\/01.NEU.0000093431.43456.3B","article-title":"Microvascular decompression for treatment of trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia: three surgical approach variations. Technical note","volume":"53","author":"Hitotsumatsu","year":"2003"},{"key":"b6-1070932","series-title":"J Hum Evol","doi-asserted-by":"publisher","first-page":"263","DOI":"10.1016\/j.jhevol.2003.08.002","article-title":"Brain expansion and comparative prenatal ontogeny of the non-hominoid primate cranial base","volume":"45","author":"Jeffery","year":"2003"},{"key":"b7-1070932","series-title":"J Neurol Neurosurg Psychiatry","doi-asserted-by":"publisher","first-page":"532","DOI":"10.1136\/jnnp.62.5.532","article-title":"Computed tomographic analysis of hemifacial spasm: narrowing of the posterior fossa as a possible factor for neurovascular compression","volume":"62","author":"Kamiguchi","year":"1997"},{"key":"b8-1070932","series-title":"Acta Neurochir (Wien)","doi-asserted-by":"publisher","first-page":"165","DOI":"10.1007\/s007010200020","article-title":"Morphometric measurements of the cranium in patients with Chiari type I malformation and comparison with the normal population","volume":"144","author":"Karagoz","year":"2002"},{"key":"b9-1070932","series-title":"Neurosurgery","doi-asserted-by":"publisher","first-page":"890","DOI":"10.1227\/00006123-198906000-00016","article-title":"The microsurgical anatomy of the infratentorial lateral supracerebellar approach to the trigeminal nerve for tic douloureux","volume":"24","author":"Matsushima","year":"1989"},{"key":"b10-1070932","series-title":"J Neurosurg","doi-asserted-by":"publisher","first-page":"1","DOI":"10.3171\/jns.1999.90.1.0001","article-title":"Microvascular decompression of cranial nerves: lessons learned after 4400 operations","volume":"90","author":"McLaughlin","year":"1999"},{"key":"b11-1070932","series-title":"Neurosurgery","doi-asserted-by":"publisher","first-page":"1005","DOI":"10.1097\/00006123-199905000-00042","article-title":"Chairi I malformation redefined: Clinical and radiolographic findings for 364 symptomatic patients","volume":"44","author":"Milhorat","year":"1999"},{"key":"b12-1070932","series-title":"J Neurosurg","doi-asserted-by":"publisher","first-page":"40","DOI":"10.3171\/jns.1997.86.1.0040","article-title":"Pathogenesis of Chiari malformation: a morphometric study of the posterior cranial fossa","volume":"86","author":"Nishikawa","year":"1997"},{"key":"b13-1070932","series-title":"Surg Neurol","doi-asserted-by":"publisher","first-page":"8","DOI":"10.1016\/S0090-3019(01)00479-7","article-title":"Posterior fossa meningiomas: Surgical experience in 161 cases","volume":"56","author":"Roberti","year":"2001"},{"key":"b14-1070932","series-title":"J Neurosurg","doi-asserted-by":"publisher","first-page":"711","DOI":"10.3171\/jns.1995.82.5.0711","article-title":"Surgical treatment of trigeminal schwannomas","volume":"82","author":"Samii","year":"1995"},{"key":"b15-1070932","series-title":"J Clin Neurosci","doi-asserted-by":"publisher","first-page":"27","DOI":"10.1016\/S0967-5868(99)90598-2","article-title":"Resection of large petroclival meningiomas by the simple retrosigmoid route","volume":"6","author":"Samii","year":"1999"},{"key":"b16-1070932","series-title":"J Neurosurg","doi-asserted-by":"publisher","first-page":"235","DOI":"10.3171\/jns.2000.92.2.0235","article-title":"Retrosigmoid intradural suprameatal approach to Meckel's cave and the middle fossa: Surgical technique and outcome","volume":"92","author":"Samii","year":"2000"},{"key":"b17-1070932","series-title":"Neurosurgery","doi-asserted-by":"publisher","first-page":"553","DOI":"10.1097\/00006123-199903000-00065","article-title":"Suprameatal extension of the retro-sigmoid approach: Microsurgical anatomy","volume":"44","author":"Seoane","year":"1999"},{"key":"b18-1070932","series-title":"Pain","doi-asserted-by":"publisher","first-page":"269","DOI":"10.1016\/0304-3959(80)90072-X","article-title":"Petrous angle and trigeminal neuralgia","volume":"8","author":"Smith","year":"1980"},{"key":"b19-1070932","series-title":"J Neurosurg","doi-asserted-by":"publisher","first-page":"719","DOI":"10.3171\/jns.1995.82.5.0719","article-title":"Comparison of conventional and skull base surgical approaches for the excision of trigeminal neurinomas","volume":"82","author":"Taha","year":"1995"},{"key":"b20-1070932","series-title":"J Clin Neurosci","doi-asserted-by":"publisher","first-page":"168","DOI":"10.1016\/j.jocn.2003.06.004","article-title":"Surgical procedure \u201cSimplified retrosigmoid approach\u201d for C-P angle lesions","volume":"11","author":"Yamashima","year":"2004"}],"container-title":["Journal of Neurosurgery"],"original-title":[],"link":[{"URL":"https:\/\/thejns.org\/view\/journals\/j-neurosurg\/107\/5\/article-p932.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/thejns.org\/downloadpdf\/journals\/j-neurosurg\/107\/5\/article-p932.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/thejns.org\/downloadpdf\/journals\/j-neurosurg\/107\/5\/article-p932.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,4,13]],"date-time":"2023-04-13T01:13:59Z","timestamp":1681348439000},"score":1,"resource":{"primary":{"URL":"https:\/\/thejns.org\/view\/journals\/j-neurosurg\/107\/5\/article-p932.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2007,11]]},"references-count":20,"journal-issue":{"issue":"5"},"URL":"https:\/\/doi.org\/10.3171\/jns-07\/11\/0932","relation":{},"ISSN":["0022-3085","1933-0693"],"issn-type":[{"value":"0022-3085","type":"print"},{"value":"1933-0693","type":"electronic"}],"subject":[],"published":{"date-parts":[[2007,11]]}}}