MRI evaluation of distance between tonsillary fossa and internal carotid artery in children

Objectives: The presence of the internal carotid artery (ICA) near tonsils can also cause severe bleeding during a tonsillectomy. We investigated the relationship between tonsil width and volume; and superior, middle and inferior tonsil-ICA distances in 5-9 and 10-15 years of age children.

Methods: Cranial MRI images of 200 children between 5 and 15 years of age were evaluated retrospectively. There were 100 children in group 1 (5-9 years of age) and 100 children in group 2 (10-15 years of age). Palatine tonsil width and volume; and superior, middle and inferior tonsil-internal carotid artery (ICA) measurements were performed bilaterally.

Results: Our results showed that bilateral tonsil width and volume; and left superior, middle and inferior tonsil-ICA distance of 5-9 years of age group were lower than those of the 10-15 year-of age group (p < 0.05). The nearest distance between ICA and palatine tonsil is at the inferior tonsil-ICA distance side in both age groups. Especially mean inferior and middle tonsil-ICA distances were lower than 8 mm in 5-9 years of age group and lower than 9 mm in 10-15 years of age group. Minimum middle tonsil-ICA distances were 2.0-2.50 mm in smaller children and 2.0-3.50 mm in older children. Similarly, the minimum inferior tonsil-ICA distances were 2.00 mm in smaller children and 2.20-3.00 mm in older children. There were positive correlations between tonsil width, volume, and superior tonsil-ICA distance; and middle and inferior tonsil-ICA distances (p < 0.05).

Conclusion: In younger children, lower tonsil width; and in all children, lower tonsil volume can be a warning sign in terms of lower tonsil superior-ICA distance. During tonsillectomies, working at the middle and inferior tonsillary fossa, maximum attention must be performed for the possibility of the ICA being very closer to the tonsil to avoid unwanted bleedings.