Mickey Mouse sign (anencephaly)
Last revised by Reabal Najjar ◉ on 13 Nov 2022
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Citation:
Botz B, Najjar R, Mickey Mouse sign (anencephaly). Reference article, Radiopaedia.org (Accessed on 03 Jun 2023) https://doi.org/10.53347/rID-99323
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99323
Article created:
26 Apr 2022, Bálint Botz ◉
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At the time the article was created Bálint Botz had no recorded disclosures.
View Bálint Botz's current disclosuresLast revised:
13 Nov 2022, Reabal Najjar ◉
Disclosures:
At the time the article was last revised Reabal Najjar had no recorded disclosures.
View Reabal Najjar's current disclosuresRevisions:
2 times, by 1 contributor - see full revision history and disclosures
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The Mickey Mouse sign in obstetric ultrasound denotes the characteristic "floating appearance" of the fetal cerebral lobes due to the absence of the cranium due to anencephaly.
Radiographic features
The sign is best seen in the coronal plane (in relation to the fetal head), where the cerebral lobes are seen floating in the amniotic fluid above the orbits (like the ears of the mouse). According to one study this sign was present in 5 out of 6 anencephalic fetuses diagnosed between 12-14 weeks of gestation 1,2.
References
- 1. Chatzipapas I, Whitlow B, Economides D. The 'Mickey Mouse' Sign and the Diagnosis of Anencephaly in Early Pregnancy. Ultrasound Obstet Gynecol. 1999;13(3):196-9. doi:10.1046/j.1469-0705.1999.13030196.x - Pubmed
- 2. Hall J, Denne N, Minardi J, Williams D, Balcik B. Check the Head: Emergency Ultrasound Diagnosis of Fetal Anencephaly. West J Emerg Med. 2016;17(4):460-3. doi:10.5811/westjem.2016.5.30326 - Pubmed
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