CC BY-NC-ND 4.0 · Asian J Neurosurg 2023; 18(01): 201-205
DOI: 10.1055/s-0043-1764119
Case Report

Fenestrated Anterior Communicating Artery Complex Mimicking an Unruptured Aneurysm: Diagnostic Pitfall

Atsushi Tsukada
1   Department of Neurosurgery, Tsukuba Memorial Hospital, Kaname, Tsukuba, Ibaraki, Japan
Kiyoyuki Yanaka
1   Department of Neurosurgery, Tsukuba Memorial Hospital, Kaname, Tsukuba, Ibaraki, Japan
Hayato Takeda
1   Department of Neurosurgery, Tsukuba Memorial Hospital, Kaname, Tsukuba, Ibaraki, Japan
Kuniyuki Onuma
1   Department of Neurosurgery, Tsukuba Memorial Hospital, Kaname, Tsukuba, Ibaraki, Japan
Maya Takada
1   Department of Neurosurgery, Tsukuba Memorial Hospital, Kaname, Tsukuba, Ibaraki, Japan
Kazuhiro Nakamura
1   Department of Neurosurgery, Tsukuba Memorial Hospital, Kaname, Tsukuba, Ibaraki, Japan
Eiichi Ishikawa
2   Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, Japan
› Author Affiliations


Anatomical variations often occur in the anterior communicating artery (AComA) complex, and a careful preoperative evaluation is required before repair of this lesion. We report a case of a fenestrated AComA complex mimicking an unruptured cerebral aneurysm. A 49-year-old woman was referred to our hospital under suspicion of unruptured aneurysms of the AComA and the left middle cerebral artery on magnetic resonance angiography (MRA). Additional three-dimensional computed tomographic angiography (CTA) showed the lesion arising from the AComA complex with a maximum diameter of 4.2 mm. Intraoperative findings showed that the putative aneurysm was actually a fenestrated AComA complex as the blood vessels that formed the AComA complex were dilated and meandering. After the operation, MRA and CTA three-dimensional images were reviewed again but we could still not diagnose the lesion as a fenestrated AComA complex rather than an aneurysm. However, in the MRA source image, a secant line in the lesion was the only finding suggestive of a fenestration. The AComA complex is often associated with various vascular malformations, and it is essential to consider this association in the preoperative evaluation. The interpretation of source images may be helpful for accurate diagnosis and surgical planning.

Authors' Contributions

Substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work: Atsushi Tsukada and Kiyoyuki Yanaka. Drafting the work: Atsushi Tsukada. Revising it critically for important intellectual content: Kiyoyuki Yanaka, Hayato Takeda, Kuniyuki Onuma, Maya Takada, Kazuhiro Nakamura, and Eiichi Ishikawa. Final approval of the version to be published: Eiichi Ishikawa and all other coauthors. Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved: Eiichi Ishikawa.

Publication History

Article published online:
31 March 2023

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