Unusual Anomaly of the Anterior Cerebral Artery

Infraoptic Course of the Anterior Cerebral Artery Originating From the Extradural Internal Carotid Artery Associated With Contralateral Internal Carotid Artery Agenesis and Multiple Intracerebral Aneurysms -Case Report-

“…The most common site of aneurysm formation is the ACA-AcomA complex. 2,4,6,7,9,[11][12][13] However, aneurysm formation may occur anywhere within the circle of Willis, such as the proximal MCA 2,3,6) and BA 3) as seen in the present case. Hemodynamic factors are likely contributors to the pathogenesis of the associated cerebral aneurysm.…”

“…In one case, the origin of the anomalous vessel appeared to be the intracavernous portion of the ICA based on angiography and intracranial exploration. 7) In another case, the anomalous vessel arose from the C 4 segment of the intracavernous ICA on conventional angiography. 4) In the last case, the infraoptic course of the ACA branched proximally to the OA origin on conventional angiography, possibly in an extradural location.…”

“…Only three cases of infraoptic course of the ACA originating from the extradural ICA have been reported. 3,4,7) We present a case of extradural origin of infraoptic course of the ACA identified with fusion images of magnetic resonance (MR) angiography and three-dimensional constructive interference in steady state (3D-CISS) MR imaging, and confirmed at surgery.…”

A Ruptured Aneurysm at the Infraoptic Azygous Anterior Cerebral Artery with the Contralateral Internal Carotid Artery Agenesis Treated by Y-stent Assisted Coil Embolization

“…Since the first reported case in 1959, approximately 50 cases of this anomaly have been reported during autopsy, surgery, or angiography 4)14)16)17). An infraoptic ACA originating from the extradural ICA was reported in only four of these previous cases 1)4)6)8). Various terminologies, including infraoptic ACA and carotid-ACA anastomosis, have been used 12)14).…”

A Rare Embryologic Variation: Anterior Communicating Artery Aneurysm Associated with Carotid–-Anterior Cerebral Artery Anastomosis or Infraoptic Course of the Anterior Cerebral Artery

“…Among patients with A ComA aneurysms hypoplasia of the A1 segment was reported for 80% of patients, according to Yaşargil, 1984 (Yaşargil, 1984), or 35% of patients according to Chioffi et al (Chioffi et al 1997), fenestration and duplication of the ACom A were reported for 4.4% (Chioffi et al 1997) and 22.4% (Yaşargil, 1984) of cases, and three distal ACAs were documented for 3.7% of the patients in the series of Chioffi et al (Chioffi et al 1997) and 9.6% of the surgical observations of Yaşargil (Yaşargil, 1984). An infraoptic course of the proximal anterior cerebral artery is a rare anomaly that has been reported in 32 cases to date, often in association with cerebral aneurysms (Bassett, 1949; Besson et al 1980; Bollar et al 1988; Brismar et al 1977; Chioffi et al 1997; Dawson, 1958; Gomes et al 1986; Kessler, 1979; Kwak et al 1980; Lasjaunias et al 2001; Mercier et al 1989; Yaşargil, 1984). …”