Topography of carotid bifurcation: considerations for neck examination

Abstract

Clinical examination and surgical procedures require the knowledge of anatomical structures of such a complex area as neck, especially the developmental anomalies in vascular drainage may occur. The aim of this study was to describe the common carotid artery bifurcation to its surrounding structures to locate it properly by using external and internal landmarks. Measurements were performed on 43 Thai cadavers by the direct inspection method. Carotid bifurcation level was compared to the level of cervical vertebra, isthmus of thyroid cartilage, angle of mandible and origins of superior thyroid artery, and lingual artery. Most of carotid bifurcations were found at the level of C3, between C3 and C4, and C4 vertebra, as well as the tendency to lower position in men was noted. Measurements to the angle of mandible on the left sides were significantly different in studied groups (P = 0.02), also with lower position of bifurcation in men. The mean level of carotid bifurcation was approximately 6 mm above ITC, which literally is at the level of the superior border of thyroid cartilage. Moreover, in four cases, common carotid artery did not bifurcate bilaterally, and in four cases, no bifurcations were found at the right side of neck. Further, many superior thyroid arteries originated from common carotid artery. To sum up, during the clinical procedures, the level of thyroid cartilage is mostly advised to follow to locate the carotid sinus. Further, the described variations in topography of carotid bifurcation and arteries origins may have important clinical implications.

Morphological variation of carotid artery bifurcation level in digital angiography

“…A lower location of the CB may obviate some manipulations during anterior cervical approach such as placement of an artificial disc or cage to the intervertebral space on account of its wider transverse diameter. The information on CB is also important for the interventions performed in the CS [12,14]. In individuals that display superior or inferior CB position, the internal pressure transmission at CS region changes and an external neck pressure stimulus causes an attenuated response in those people when compared to the individuals with a CS located in the middle part of the neck [18].…”

“…In individuals that display superior or inferior CB position, the internal pressure transmission at CS region changes and an external neck pressure stimulus causes an attenuated response in those people when compared to the individuals with a CS located in the middle part of the neck [18]. Therefore, it is important to know the location of CS during cervical lymph node palpation due to likelihood of syncope during this examination [12].…”

“…The bifurcation level was above C4 level in 9.4% of the female and 5.9% of the male, when both sides were taken into account. A bifurcation level above C4 level was reported in 2.4% of the patients in Klosek and Rungruang's [12], in 1% of the patients in Gluncic et al's [6], and in 10% of the patients in Anu et al's [2] studies.…”

“…Ito and associates reported a high common CB in 25 (31.2%), a standard bifurcation (C4) in 46 (57.5%), and low bifurcation in 9 (11.3%) patients in their series of 80 cases [9]. Klosek and Rungruang [12] performed a study on 43 cadavers, and found the absence of ECA unilaterally in 4, and bilaterally in 4 cases. Bregman et al [3] also reported the absence of ECA.…”

Variation in the Caudal Branches of the External Carotid Artery: Comparison of Sex and Side

“…Previous studies have shown that multiple ECA branching patterns exist (Gupta et al 2014, Hayashi et al 2005, Kamenskiy et al 2012, Kitagawa 1993, Klosek and Rungruang 2008, Lo et al 2006, LuČev et al 2000, Natsis et al 2011, Ozgur, Govsa, and Ozgur 2008, Sanjeev et al 2010, Shintani et al 1999, Toni et al 2004, Vázquez et al2009, Yonenaga et al 2011, Zümre et al 2005. Classic textbook representations of the ECA and the origins of its eight branches vary significantly depending on source (Drake, Vogl, and Mitchell 2005, Gilroy et al 2008, Moore, Dalley, and Agur 2009, Netter 2010.…”