Author: Deepali Jain, M.D. (see Authors page)

Revised: 27 April 2018, last major update March 2013

Copyright: (c) 2003-2018, PathologyOutlines.com, Inc.

PubMed Search: Cyclopia [title] eye

Cite this page: Jain, D. General: cyclopia. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/eyecyclopia.html. Accessed October 15th, 2018.
Definition / general
  • Rare (1 per 100K births) congenital abnormality with one medial eye (either single eye or 2 fused eyeballs) and proboscis (tubular appendage) superior to the orbit
  • Incompatible with life
  • Most severe facial expression of holoprosencephaly
  • Due to impaired midline cleavage of embryonic forebrain causing doubling of intrinsic ocular structures; may be associated with malfunction of sonic hedgehog protein
  • Female predominance (58%)
  • Associated with trisomy 13, trisomy 18, triploidy; also other chromosomal abnormalities (Am J Med Genet C Semin Med Genet 2011;157C:344)
Case reports
Clinical images

Images hosted on other servers:
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Single orbit with 2 fused eyes

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Trisomy 13 - cyclopia with proboscis