{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T14:17:16Z","timestamp":1791209836183,"version":"4.1.0"},"reference-count":11,"publisher":"Cambridge University Press (CUP)","issue":"3","license":[{"start":{"date-parts":[[2014,12,2]],"date-time":"2014-12-02T00:00:00Z","timestamp":1417478400000},"content-version":"unspecified","delay-in-days":1311,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Can. J. Neurol. Sci."],"published-print":{"date-parts":[[2011,5]]},"abstract":"Purpose:<\/jats:title>To determine if there is a correlation between cerebellar tonsillar descent in patients with and without Chiari I malformation and three skull morphometric measurements: clivus length, anteroposterior diameter of the foramen magnum, and Boogard's angle.<\/jats:p><\/jats:sec>Methods:<\/jats:title>Cerebellar tonsillar descent, clivus length, anteroposterior diameter of the foramen magnum, and Boogard's angle were measured in mid-sagittal T1-weighted magnetic resonance images of 188 patients. The study included 81 patients with Chiari I malformations (CMI). Without identifiable pathology, 107 patients served as a comparison group. Two-sample t-tests were used to assess for significance. A Pearson correlation matrix was constructed to assess the strength of linear dependence between measured parameters for the study population.<\/jats:p><\/jats:sec>Results:<\/jats:title>A negative correlation was found between tonsillar herniation and clivus length (r = -0.30, P<\/jats:italic> < 0.001), while a positive correlation was found between tonsillar herniation and foramen magnum size (r = 0.15, P<\/jats:italic> = 0.0431), and Boogard's angle (r = 0.23, P<\/jats:italic> = 0.0014). Clivus length was shorter (P<\/jats:italic> = 0.0009) in CMI patients (4.02 cm \u00b1 0.45) than comparison patients (4.23 cm \u00b1 0.42). In addition, the anteroposterior diameter of the foramen magnum was wider (P<\/jats:italic> = 0.0412) (3.74 cm \u00b1 0.40 compared to 3.63 \u00b1 0.30) and Boogard's angle was larger (P<\/jats:italic> = 0.0079) (123.58 degrees \u00b1 8.27 compared to 120.62 degrees \u00b1 6.79) with CMI.<\/jats:p><\/jats:sec>Conclusion:<\/jats:title>A greater degree of cerebellar tonsillar herniation is associated with a shorter clivus length, a wider anteroposterior diameter of foramen magnum, and a wider Boogard's angle.<\/jats:p><\/jats:sec>","DOI":"10.1017\/s0317167100011860","type":"journal-article","created":{"date-parts":[[2014,12,12]],"date-time":"2014-12-12T10:10:13Z","timestamp":1418379013000},"page":"452-455","source":"Crossref","is-referenced-by-count":46,"title":["Posterior Fossa Measurements in Patients With and Without Chiari I Malformation"],"prefix":"10.1017","volume":"38","author":[{"given":"John A.","family":"Dufton","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Syed Yaser","family":"Habeeb","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manraj K. S.","family":"Heran","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David J.","family":"Mikulis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Omar","family":"Islam","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"56","published-online":{"date-parts":[[2014,12,2]]},"reference":[{"key":"S0317167100011860_ref004","doi-asserted-by":"publisher","DOI":"10.1186\/1743-8454-2-11"},{"key":"S0317167100011860_ref010","doi-asserted-by":"publisher","DOI":"10.3171\/2009.2.JNS08284"},{"key":"S0317167100011860_ref001","first-page":"795","article-title":"Significance of cerebellar tonsillar position on MR","volume":"7","author":"Barkovich","year":"1986","journal-title":"Am J Neuroradiol"},{"key":"S0317167100011860_ref005","doi-asserted-by":"publisher","DOI":"10.1016\/0022-510X(87)90018-9"},{"key":"S0317167100011860_ref006","doi-asserted-by":"publisher","DOI":"10.1016\/0022-510X(90)90150-L"},{"key":"S0317167100011860_ref008","doi-asserted-by":"publisher","DOI":"10.1007\/s007010200020"},{"key":"S0317167100011860_ref009","doi-asserted-by":"publisher","DOI":"10.1016\/j.surneu.2005.02.021"},{"key":"S0317167100011860_ref011","doi-asserted-by":"publisher","DOI":"10.1007\/BF00593966"},{"key":"S0317167100011860_ref002","doi-asserted-by":"publisher","DOI":"10.1097\/00006123-199905000-00042"},{"key":"S0317167100011860_ref003","doi-asserted-by":"publisher","DOI":"10.3171\/jns.2000.92.6.0920"},{"key":"S0317167100011860_ref007","doi-asserted-by":"publisher","DOI":"10.3171\/jns.1997.86.1.0040"}],"container-title":["Canadian Journal of Neurological Sciences \/ Journal Canadien des Sciences Neurologiques"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0317167100011860","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,4,11]],"date-time":"2019-04-11T17:01:01Z","timestamp":1555002061000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0317167100011860\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2011,5]]},"references-count":11,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2011,5]]}},"alternative-id":["S0317167100011860"],"URL":"https:\/\/doi.org\/10.1017\/s0317167100011860","relation":{},"ISSN":["0317-1671","2057-0155"],"issn-type":[{"value":"0317-1671","type":"print"},{"value":"2057-0155","type":"electronic"}],"subject":[],"published":{"date-parts":[[2011,5]]}}}