Morphological characteristics of the external carotid artery

The morphological characteristics at the level of the bifurcation of the common carotid artery were studied on 46 cases, finding that the most frequent, in 52.17% of cases, the common carotid bifurcation appear as the letter “V”, with two possible variations: a wide “V”, in 43.48% of cases and narrow “V” in 8.7% of cases. In 30.43% of cases, the two carotids showed an ascending traject, united for 1-2 cm up to their crossing; in 13,04% of the cases the two arteries were superimposed, the external located anteriorly. In only in two cases on the right side (4.35% of cases and 8.33% of right samples) we found a peculiar aspect of a “U” shaped bifurcation. Regarding the caliber of the external carotid artery, we found that in 43.33% of the cases the external carotid artery had a similar diameter to the internal carotid, also in 43.33% of the external carotid artery have a higher caliber than internal one and the remaining 13.33% of the cases, the external carotid artery had a smaller diameter than the internal one, with all cases on the left (16.67% of left carotid arteries). The caliber of the right external carotid artery was between 4 to 5.6 mm and the one of the left was between 3.6 to 5 mm. When the external carotid was more voluminous than the internal, the differences were 0.5 to 1.2 mm and when the internal carotid was more voluminous than the external, the differences were smaller, 0.2 to 0.8 mm. In relation to the common carotid, the external carotid had a smaller caliber from 0.6 to 1.1 mm. Regarding the external carotid traject, most commonly, from the bifurcation of the common carotid, the external carotid artery showed a vertical trajectory, in 50% of cases; in 40% of cases, the traject was oblique superomedially and in 6.67% of cases the external carotid artery described a curve with the convexity facing laterally, with all cases on the right (11.76% of right carotid arteries); in 3.33% of cases, both on the left (7.69% of the left carotid arteries), the external carotid artery traject described an inverted italic “S”