Frog eye sign
Last revised by Bálint Botz on 27 Apr 2022
Citation, DOI, disclosures and article data
Citation:
Botz B, Frog eye sign. Reference article, Radiopaedia.org (Accessed on 19 Apr 2024) https://doi.org/10.53347/rID-99322
Permalink:
rID:
99322
Article created:
26 Apr 2022,
Bálint Botz ◉
Disclosures:
At the time the article was created Bálint Botz had no recorded disclosures.
View Bálint Botz's current disclosures
Last revised:
27 Apr 2022,
Bálint Botz ◉
Disclosures:
At the time the article was last revised Bálint Botz had no recorded disclosures.
View Bálint Botz's current disclosures
Revisions:
1 time, by
1 contributor -
see full revision history and disclosures
Systems:
Sections:
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
Incoming Links
Articles:
Related articles: Malformations of the central nervous system
-
malformations of cortical development
- abnormal cell proliferation or apoptosis
- abnormal brain size
-
microcephaly
- with normal to simplified cortical pattern
- microcephaly with lissencephaly
- microcephaly with extensive polymicrogyria
- macrocephalies (megalencephaly/macrocephaly)
-
microcephaly
- abnormal cell proliferation
- non-neoplastic
- cortical hamartomas of tuberous sclerosis
- hemimegalencephaly
-
focal cortical dysplasia (Type I and Type IIb)
- Palmini classification (2004)
- Barkovich classification (2005)
- Blumcke classification (2011)
- neoplastic
- non-neoplastic
- abnormal neuronal migration
- lissencephaly
- lissencephaly type I: subcortical band heterotopia spectrum (band heterotopia): undermigration
- lissencephaly type II (cobblestone complex)
- heterotopia: ectopic migration
- subependymal heterotopia
- subcortical heterotopia (not including band heterotopia)
- marginal glioneuronal heterotopia
- lissencephaly
- abnormal cortical organization
- mild malformations of cortical development (previously microdysgenesis)
-
polymicrogyria and schizencephaly
- bilateral polymicrogyria syndromes
- schizencephaly
- focal cortical dysplasia (Type IIa)
- abnormal brain size
- not otherwise classified
- malformations secondary to inborn errors of metabolism
- mitochondrial and pyruvate metabolic disorders
- peroxisomal disorders
- other unclassified malformations
- malformations secondary to inborn errors of metabolism
- abnormal cell proliferation or apoptosis
-
midline abnormalities of the brain
- absent septum pellucidum
- cephaloceles
-
midline nasal region lesions
- nasal dermoid
- nasal glioma
- nasal dermal sinus
- cerebral hemispheres
-
holoprosencephaly/septo-optic dysplasia spectrum
- septo-optic dysplasia
- lobar holoprosencephaly
- semilobar holoprosencephaly
- alobar holoprosencephaly
- middle interhemispheric variant/syntelencephaly
-
holoprosencephaly/septo-optic dysplasia spectrum
- corpus callosum
- intracranial lipoma
-
malformations of the cerebellum
- cerebellar hypoplasia
- focal hypoplasia
- generalized hypoplasia
- with enlarged fourth ventricle
- normal fourth ventricle
- with normal pons
- with small pons
- normal foliation
- pontocerebellar hypoplasias of Barth, types I and II
- cerebellar hypoplasias, not otherwise specified
- normal foliation
- cerebellar dysplasia
- focal dysplasia
- isolated vermian dysplasia
- molar tooth malformations including Joubert syndrome
- rhombencephalosynapsis
- isolated hemispheric dysplasia
- focal cerebellar cortical dysplasias/heterotopia
- dysplastic cerebellar gangliocytoma
- isolated vermian dysplasia
- generalized dysplasia
- congenital muscular dystrophies
- cytomegalovirus
- lissencephaly with RELN mutation
- lissencephaly with agenesis of corpus callosum and cerebellar dysplasia
- associated with diffuse cerebral polymicrogyria
- diffusely abnormal foliation
- focal dysplasia
- cerebellar hypoplasia
- malformations of the brainstem
Unable to process the form. Check for errors and try again.