Smaller caliber of the internal carotid artery in patients with ipsilateral aplasia of the A1 segment of the anterior cerebral artery: a study with CTA

Abstract

To measure the diameter and the transsectional area of the internal carotid arteries (ICA) on CT Angiography (CTA) in patients with aplasia of the A1-segment of the ACA (A1) and in patients with symmetrical A1, the mean diameter and area of the ICA on both sides were measured at a level of 2 cm below the skull base with a commercially available CT software in 41 consecutive patients with aplasia of A1 observed during a 12-month period on CTA and in 41 control patients with symmetrical A1. The mean diameter of the ipsilateral ICA was 3.83 ± 0.60 mm versus 4.86 ± 0.60 mm as mean diameter of the contralateral ICA and versus 4.40 ± 0.60 mm as mean diameter of both ICAs in the control group of patients. The mean area of the ipsilateral ICA was 11.58 ± 3.80 mm versus 18. 82 ± 7.39 mm as mean area of the contralateral ICA and versus 15.29 ± 4.42 mm as mean area of both ICA in the control group of patients. These differences are statistically highly significant. In patients with symmetrical A1, there was no statistical difference between the diameter or area of both internal carotid arteries. In conclusion, in patients with aplasia of A1, the ipsilateral diameter and area of the cervical ICA is smaller than the diameter and area of the contralateral ICA and smaller than the diameter and area of both internal carotid arteries in patients with symmetrical A1.

Two cases of combined anatomical variations: maxillofacial trunk, vertebral, posterior communicating and anterior cerebral atresia, linguofacial and labiomental trunks

“…This is a rare finding, but the most frequently observed variation of the anterior cerebral artery [37]. Lippert and Pabst indicated this variant to occur in 10% of cases [20], Carels et al found it in 10.5% [6], but Uchino et al (2006) observed it in just 5.6% of cases [37].…”