Proboscis is a rare congenital anomaly where an anterior appendage-like structure is seen projecting from the midline fetal face/forehead. Depending on the exact location, this has further been classified into various subtypes (e.g. interorbital proboscis).
The presence of a proboscis can be associated with several anomalies which include:
- trisomy 13
- ethmocephaly 3
- cyclopia: often below the level of the proboscis
A proboscis is best seen on a longitudinal facial profile view as a snout-like protrusion from the face/forehead.
History and etymology
'Proboscis' is derived from the Ancient Greek προβοσκις (proboskis), itself derived from the words πρό (pro) meaning: "forth/forward/before" and βόσκω (bosko) meaning: "to feed".
- proboscis lateralis: considered a different entity
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