The carotid–hyoid topography is variable
A bilateral CTA study that replaces the idea of one fixed carotid–hyoid relationship with a 12-type topographic classification plus a null state.
The greater hyoid horn can relate to different segments of the carotid axis.
Twelve direct carotid–hyoid patterns were defined on CTA, and no direct relationship was present on more than half of sides. The result is a practical argument for case-by-case imaging rather than a fixed textbook template.
CTA reveals more than the textbook relationship
The study examined 147 CT angiograms bilaterally and classified direct relationships between the carotid axis and the greater horn of the hyoid bone.
Patients
Retrospective CTA sample.
Sides
Both carotid axes assessed.
Direct relationship
One of Types I–XII was identified.
Bilateral symmetry
Including the null relationship and symmetric variants.
Thirteen states: null plus Types I–XII
Choose a state to see which carotid segment lies medial or lateral to the greater horn of the hyoid bone and how often it occurred.
The common patterns are lateral, not medial
Type VI—ECA lateral to the greater hyoid horn—was the dominant direct relationship; several medial or crossed patterns were rare.