• Andrei F Joaquim, Evangelista Santos BarcelosAlécio CristinoACDivision of Neurosurgery, Hospital Municipal Santa Isabel, Joao Pessoa, Paraíba, Brazil., Jefferson Walter Daniel, and Ricardo Vieira Botelho.
• Department of Neurology, Discipline of Neurosurgery, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil. Electronic address: andjoaquim@yahoo.com.
• World Neurosurg. 2023 May 1; 173: e364e370e364-e370.

ObjectiveTo compare the measured odontoid tip violation above Chamberlain's line described in the literature to diagnose basilar invagination (BI) and to establish the normal placement of the dens tip defining individuals without BI (normal subjects).MethodsA systematic literature review was performed to identify clinical or radiological studies that expressed the amount of odontoid violation above Chamberlain's line in patients with a BI diagnosis. In addition, a meta-analysis was performed to evaluate normal subjects' values of Chamberlain's line violation (CLV).ResultsThere were 23 studies included (13 radiological and 10 clinical). Most studies used computed tomography and/or magnetic resonance imaging. Eight different cutoff values were used to measure dislocated odontoid apexes above Chamberlain's line regardless of the radiological modality. The mean measured amount of CLV was 3.95 mm (median 5 mm; range, 0-9 mm). The meta-analysis included 8 studies (1233 patients) with a normal sample population with a mean normal CLV of -0.63 mm (below the line) (95% confidence interval [-0.8, 1.18 mm], random effects model).ConclusionsDifferent values were found in the assessed studies used for CLV in BI diagnosis. This variability is especially important for type B BI, as type A BI has other craniocervical diagnostic parameters. Considering the results obtained in this meta-analysis, BI should be diagnosed in the case of any dens violation >1.18 mm.Copyright © 2023 Elsevier Inc. All rights reserved.

14 keywords...

hide…