Endovascular treatment of an “anterior cerebral artery” aneurysm in a patient with “embryonic unfused middle cerebral artery” anomaly: a case report

Abstract

We report a unique case of an anterior cerebral artery aneurysm in a patient with embryonic unfused middle cerebral artery anomaly. The arterial twigs of the middle cerebral artery supply the entire middle cerebral artery territory including the lenticulostriate branches. There was a vessel incorporated into the aneurysm, which was referred to as an accessory middle cerebral artery and it gave rise to a lenticulostriate branch. The aneurysm was occluded with detachable coils using a remodeling technique. After successful occlusion of the aneurysm the so-called accessory middle cerebral artery including its lenticulostriate branch started to fill from the anomalous middle cerebral artery network and the patient did not experience any ischemic injury.

Unfused or twig-like middle cerebral artery

“…Cekirge et al [3] reported one case and named this variation as unfused MCA, despite that Liu et al [16] reported two cases and named them as twig-like MCA. In 2011, Rodríguez-Hernández et al [17] Ipsilateral cingulate gyrus AVM (n = 1) * Four of these 15 cases were termed as probable Uf/Tw MCA by the author.…”

“…Later these twigs coalesce and form a more prominent large single branch [2,9]. Early interruption during the coalescing period results in a plexiform arterial network appearance [3]. ACA is the terminal branch of ICA and embryologically, a group of lateral striate arteries develop from the proximal ACA to supply the growing telencephalon.…”

“…Variations in the middle cerebral artery (MCA) territory seems to be less frequent than the other intracranial arteries. Variations of MCA are rare although early branching, duplication, fenestration and accessory middle cerebral artery are the well defined variations of MCA with an incidence of 0.17-4% in angiographic and postmortem studies [3][4][5][6][7][8]. Many comprehensive studies about the variations of the intracranial vasculature did not reveal the embryologic unfused or twig-like (Uf/Tw) variation of the MCA [1,2,[4][5][6][10][11][12].…”

“…1). The pattern is also defined as aplastic or unfused MCA in the literature [3,13]. Our aim is to define and evaluate the angiographical features of Uf/Tw MCA.…”

Anomalies of the Middle Cerebral Artery

“…In 2005, Cekirge et al reported one case of an occluded MCA trunk with collateral plexiform arterial network and named this variation as embryonic unfused MCA, 9) and Liu et al reported two cases and named them as twig-like MCA. 8) In 2012, Seo et al reported the largest series with 15 cases and named the finding as aplastic or twig-like MCA.…”