An excess vessel in the posterior part of the human cerebral arterial circle (CAC): a case series

Abstract

BackgroundAs a continuation of the previous findings in human fetuses, accidental finding of an accessory vascular component in the posterior part of CAC of human adult cadavers inspired the authors to present and compare its posterior part configuration.Case presentationExamination was carried out on brains of 48 human adult cadavers, routinely dissected at the Institute of Forensic Medicine. The aberrant vessel in the posterior part of four CACs was discovered.Vascular components of the posterior segment of CAC or of the whole CAC were described and photographed. A comparison between fetal and adult cases was also presented.ConclusionsBased on the fact that the age of the four presented cases ranged from 73 to 84 and based on the causes of their death, we concluded that the angioarchitecture of the posterior part of the CAC is a consequence of the embryonic or primitive arterial stabilization and interaction with normal adult vessels.

Types and Subtypes of the Posterior Part of the Cerebral arterial Circle in Human Adult Cadavers

“…The "typical" circle of Willis was defined with respect to its components as a closed circuit in which fluid may circulate from any entrance point back to the same point with all vessels more than 1 mm in external diameter and with no excess vessels (Kayembe et al, 1984). Variable five vascular components in the circle posterior part are previous described in fetuses and adults (Vasović, 2004;Vasović et al, 2010). Many authors wide world have studied about the length, diameter and anomalies in the origin of vascular components of the circle of Willis and found that the parameters in different geographical limits were different.…”

“…The integrity of the circle of Willis may be critical because anomalies and hypoplasia of the circle of Willis are frequent (Merkkola et al, 2006). Anomalies found in a pattern of the posterior part of the circle of Willis result due to persistence of vessels that normally disappear or disappearance of normal vessels (Vasović, 2004;Kapoor et al, 2008;Vasović et al, 2010). Although the association of variations and aneurysms had been used as an argument in favor of a congenital theory of aneurismal development, it should be interpreted in terms of the hemodynamic stress caused by variations (Kayembe et al, 1984).…”

Association of two primitive carotid-basilar anastomoses and cerebrovascular abnormalities on the brain base: a case report

“…According to this opinion, we considered that ICoA is a CVBA. The presence of this supernumerary vessel in the CAC was proved in 7/200 fetuses (16), and 4/48 adult cadavers (17). The coexistence of the PPTA and ICoA in this and previous cases (18), or the PPTA and another CVBA (14,24), could be related to an underlying embryologic dysgenesis or a common insult resulting in vascular maldevelopment during the first several gestational weeks.…”

“…In this, as well as in previous cases (16)(17)(18), the cerebral arterial circle (CAC) with an ICoA connecting two right PCAs can be compared with a decagon. We think that the right PCA of basilar origin is a continuation of primitive longitudinal neural artery on this side, while the PCA of carotid origin and ICoA were branches of a caudal end of primitive ICA.…”

The vascular patterns of the posterior part of the circulus arteriosus cerebri (Willisi)

“…This plexus may persist postnatally as the single intermediate communicating artery, which explains the origin of the vascular anastomosis joining the doubled PCA. The persistence of the vestigial vessels of the internal carotid and vertebrobasilar systems or the carotid-basilar anastomoses explains the cases of vascular duplication and fenestration (14,16).…”