Background: Unruptured cerebral aneurysms (UCAs) might lead to a poor outcome. However, the previously reported prevalence of UCAs in Japan ranges widely.
Method: The objects of this retrospective and hospitalbased study were adult residents of Okinoerabu, a small island in Japan. We performed the examination of the brain with 1.5-Tesla MR angiography (MRA) from December 2017 to May 2018 at Okinoerabu Tokushukai Hospital. We estimated the prevalence of UCAs and investigated the characteristics of UCAs.
Results: Thirty UCAs were found in 27 of 356 persons. 3 persons had multiple UCAs. The overall prevalence was 7.6% (Men 7.3%; Women 7.8%). Except for one person, UCAs were identified in those over 50 years old and women in 5th decade showed the highest prevalence (14.3%). More than half of UCAs located in the internal carotid artery (ICA, 56.7%). Most UCAs had a maximum diameter less than 4.9 mm (93.3%).
Conclusion: The overall prevalence of UCAs in Okinoerabu was comparatively high on Okinoerabu. The characteristics of UCAs were as follows: over 5th decade, in ICA, and smaller than 4.9 mm.
Hisashi Ito, Tazuyo Kawaminami, Kayo Asano, Tomoko Fukunaga, Kiyomi Edura, Chiseko Karai, Satsuki Okuma, Sachiko Takeshita, Motokazu Tsutsumi, Yoshihiro Tokeshi and Tetsuya Itagaki