Topography of the Anatomical Landmarks of Carotid Bifurcation and Clinical Significance

Abstract

Objective: Carotid bifurcation (CB) and its terminal branches are the most common sites of atherosclerotic plaques. In surgical treatment, these plaques can be reached by an endarterectomy technique. The success of the technique can be achieved with good anatomical knowledge of these arteries and their relationships with surrounding structures.Materials and methods: The study was performed retrospectively on archived images of patients with computed tomography angiography (CTA). Two hundred forty-seven patients who met the criteria were included in this study. Three-dimensional (3D) reconstructions of two-dimensional CTA images were made automatically using the open-source software Horos v.4.0.0. The distance between the transverse plane passing through the bifurcation point (BP) and the defined planes of the surrounding structures was evaluated.Results: CB was observed below the mastoid process, gonion point, and hyoid bone. CB was observed above the thyroid cartilage. Carotid bifurcation was seen at 15 levels in total, the lowest in the upper 1/3 of the C6 vertebral body and the highest in the lower 1/3 of the C2 vertebral body. In all cases, the most common level was the C3 lower level. Conclusion: All these values, which emerged as a result of the study, provide general information about the topography of the CB according to the neighboring structures. Estimating the location of the CB according to the gonion and hyoid bone will give a more accurate result. The vertebral level on the right side increased in direct proportion to age; there was no similar relationship on the left side. It is necessary to be aware of these anatomical variations in order to prevent various iatrogenic complications.

The vertical topography of the carotid bifurcation – original study and review

“…Different vertical locations of the CB were found in the present study and others [ 1 , 3 – 5 , 9 , 11 , 12 , 14 , 17 , 19 , 21 , 24 , 25 , 27 – 37 ]. As presented in Table 7 , different studies observed only the vertebral level of the CB; other authors studied the CB in relation to different anterior cervical landmarks, while a few authors observed both vertebral and anterior cervical landmarks.…”

“…Our results converge with the conclusions of a previous study of the anterior and posterior landmarks of the CB. Cihan and Deveci (2022) concluded that estimating the CB’s location according to the gonion and hyoid bone will give a more accurate result [ 11 ]. Cobiella et al (2021) used the body of the hyoid bone level as a single landmark for the CB [ 12 ].…”

“…Chalise et al (2021) studied the vertebral level of CB in 18 cadavers; it ranged from C2/C3 to C4 [ 9 ]. Cihan and Deveci (2022) found the highest vertebral level of CB in the lower 1/3 of the C2 vertebra and the lowest level in the upper 1/3 of the C6 vertebra [ 11 ].…”

The Axial Spin of the Carotid Bifurcation

“…However, the anatomy of the CB is highly variable concerning its vertical position [11][12][13][14][15], its relationship with the hyoid bone [16], and its axial spin. In previous studies, the vertical position of the CB was referred to vertebral landmarks, anterior cervical landmarks, or both [17][18][19][20][21][22][23][24][25][26]. The twisted carotid artery (TCA)-or ECA and ICA transposition, or twisted CB-is a variant in which the ICA is medial to the ECA [27,28].…”