Spontaneous disappearance of an intracranial small unruptured aneurysm on magnetic resonance angiography: Report of two cases

Yu Akimoto; Kiyoyuki Yanaka; Kuniyuki Onuma; Kazuhiro Nakamura; Nobuyuki Takahashi; Eiichi Ishikawa

doi:10.4103/ajns.AJNS_281_20

Asian Journal of Neurosurgery, Table of Contents

CC BY-NC-ND 4.0 · Asian J Neurosurg 2020; 15(04): 1055-1058
DOI: 10.4103/ajns.AJNS_281_20

Case Report

Spontaneous disappearance of an intracranial small unruptured aneurysm on magnetic resonance angiography: Report of two cases

Yu Akimoto

Department of Neurosurgery, Tsukuba Memorial Hospital, Tsukuba, Ibaraki

,

Kiyoyuki Yanaka

Department of Neurosurgery, Tsukuba Memorial Hospital, Tsukuba, Ibaraki

,

Kuniyuki Onuma

Department of Neurosurgery, Tsukuba Memorial Hospital, Tsukuba, Ibaraki

,

Kazuhiro Nakamura

Department of Neurosurgery, Tsukuba Memorial Hospital, Tsukuba, Ibaraki

,

Nobuyuki Takahashi

¹Department of Radiology, Tsukuba Memorial Hospital, Tsukuba, Ibaraki

,

Eiichi Ishikawa

²Department of Neurosurgery, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki

› Author Affiliations

Abstract

Spontaneous radiographic disappearance of cerebral aneurysms is often observed under special conditions such as giant aneurysms. However, spontaneous disappearance of an unruptured and nongiant intracranial saccular aneurysms is rare. We describe two cases of this rare vascular phenomenon. The first patient is a 64-year-old female diagnosed with a small unruptured aneurysm arising from the distal anterior cerebral artery. Spontaneous disappearance of the aneurysm on magnetic resonance angiography (MRA) was observed 5 years after the initial diagnosis. Continuous imaging surveillance also revealed spontaneous reappearance of the aneurysm 2 years later. The second patient is a 57-year-old female harboring a small unruptured saccular aneurysm arising from the M1–M2 bifurcation of the middle cerebral artery. The aneurysm showed spontaneous disappearance on MRA 13 years after the initial diagnosis. These cases provide a new insight into this natural dynamic process even in cases of a small unruptured intracranial saccular aneurysm.

Key-words:

Spontaneous disappearance - thrombosis - unruptured cerebral aneurysm

Full Text

References

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