Distance Between the Tonsillar Fossa and Internal Carotid Artery in Children

Abstract

OBJECTIVE: Obtain normative data on the distance from the tonsillar fossa to the internal carotid artery in children, and relate this distance to age and weight parameters. DESIGN: A prospective study of 100 children undergoing magnetic resonance imaging studies for pathology unrelated to the upper aerodigestive tract. The torus tubarius corresponds to the lateral extent of the tonsillar fossa and was used as the reference site for measurements. One hundred children (aged 7 days to 18 years; median, 6 years) were consecutively entered into the study. Exclusion criteria included any preexisting abnormalities of the upper aerodigestive tract. The study defined the distance from the tonsillar fossa to the internal carotid artery. Relationships of this distance were defined for both age and weight parameters. RESULTS: With increasing age and weight, the distance between the tonsillar fossa and the internal carotid artery increases in a regular fashion to a value approaching 25 mm. Both relationships are exponential with asymptotes being achieved by 56 kg (correlation coefficient, 0.8616; R2 value, 0.7423) or 12 years of age (correlation coefficient, 0.8452; R2 value, 0.7143). CONCLUSION: Age and weight parameters can be used to predict the distance from the tonsillar fossa to the internal carotid artery in children.