Frog eye sign
Last revised by Dr Bálint Botz ◉ on 27 Apr 2022
Citation, DOI & article data
Citation:
Botz, B. Frog eye sign. Reference article, Radiopaedia.org. (accessed on 26 May 2022) https://doi.org/10.53347/rID-99322
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rID:
99322
Article created:
26 Apr 2022 by Dr Bálint Botz ◉
Revisions:
2 times by 1 users - see full revision history
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Synonyms:
The frog eye sign is seen when the orbital structures show a characteristic protrusion due to fetal anencephaly. The term is particularly used in point of care ultrasound (POCUS) 1.
Radiographic features
On obstetric ultrasound the frog eye sign is best appreciated in the coronal plane (in relation to the fetal head). The protruding orbital structures is due to the absence of the fetal calvarium and cerebral tissues cephalad to the orbits. This sonographic appearance is best seen from the second trimester 1,2.
References
- 1. 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
- 2. 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
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