embryotoxon

embryotoxon

 [em″bre-o-tok´son]
anterior embryotoxon arcus corneae.
posterior embryotoxon Axenfeld's anomaly.

em·bry·o·tox·on

(em'brē-ō-tok'sŏn),
Congenital opacity of the periphery of the cornea, a feature of osteogenesis imperfecta.
[embryo- + G. toxon, bow]

embryotoxon

/em·bryo·tox·on/ (em″bre-o-tok´son) a ringlike opacity at the margin of the cornea.
anterior embryotoxon  embryotoxon.
posterior embryotoxon  a developmental anomaly in which there is a ringlike opacity at Schwalbe's ring, with thickening and anterior displacement of the latter; it is seen in Axenfeld's syndrome and Rieger's syndrome.

em·bry·o·tox·on

(em'brē-ō-tok'son)
Congenital opacity of the periphery of the cornea, caused by thickening and anterior displacement of the Schwalbe line.
Synonym(s): Axenfeld anomaly.
[embryo- + G. toxon, bow]
References in periodicals archive ?
1) He referred to this abnormality as embryotoxon corneae posterius.
DISCUSSION: Posterior embryotoxon is a congenital anomaly, considered to be a relatively mild disorder and can occur as an isolated defect.
As the trabecular meshwork is also derived from the neural crest, it stands to reason that patients with posterior embryotoxon are predisposed to open-angle glaucoma.
SUMMARY: This case is unique of its own kind due to rare association of bilateral posterior embryotoxon in the cornea with cardiac anomalies consisting of VSD, PA, PDA and maxillary hypoplasia.
Posterior embryotoxon may not be a forme fruste of Axenfeld-Rieger's syndrome.
Axenfeld anomaly also called posterior embryotoxon, is a congenital anomaly in which Schwalbe's line is anteriorly displaced and is associated with iris bands that extend to the cornea.
Axenfeld characterized the anomaly which bears his name when he described posterior embryotoxon and iris strands adherent to the anteriorly displaced Schwalbe's line (1920).
Posterior embryotoxon is a clinical and histological term referring to displacement of Schwalbe's line.
DISCUSSION: Anterior segment dysgenesis is a group of rare autosomal dominant condition including posterior embryotoxon, Axenfeld-Rieger syndrome, Peter's anomaly and aniridia.
In 1920, axenfeld characterised the anomaly which bears his name when he described posterior embryotoxon and iris strands adherent to the anteriorly displaced schwalbe's line (1).
1), eye changes in the form of iris hypoplasia, polycoria (multiple pupils), corectopia (eccentrically placed pupil), posterior embryotoxon (white rim of cornea), which refers to displacement of schwalbe's line anterior to limbus in the cornea.
The iris strands adherent to posterior embryotoxon can range from thin strands to broad bands.