Coloboma

from Wikipedia, the free encyclopedia
Classification according to ICD-10
Q10.3 Other congenital malformations of the eyelid
- eyelid coloboma
Q12.2 Lentil coloboma
Q13.0 Iris coloboma
Q14.2 Congenital malformation of the papilla
- coloboma of the papilla
Q14.8 Other congenital malformations of the back of the eye
- coloboma of the fundus
ICD-10 online (WHO version 2019)

A coloboma (from ancient Greek κολόβωμα kolóbōma , part removed when mutilated) is understood in the broadest sense as congenital or acquired cleft formation.

An ocular coloboma is a gap in the area of ​​the eye that can affect the iris , lens , retina , choroid , optic nerve papilla and / or the eyelid . The effects depend on the extent and size.

Pathogenesis

Congenital coloboma

Eyes of a one-year-old child with congenital cleft formation in the right iris ( iris coloboma )
The embryonic eye development leads via the
ocular vesicle to the eye cup (shown) and thus to a crevice that is normally closed completely later.
Iris coloboma in a 16 year old

Congenital cleft formation is the result of disturbances in the embryonic development of the eye and is assigned to inhibition malformations . Due to lack driven processes is omitted, a complete closure of the eye cup column that after the invagination ( intussusception ) of the optic vesicle regularly arises at the optic cup between the envelope folds.

Since the embryonic eye-cup gap points in the direction of the eye-cup stem and nasally below, the congenital iris coloboma is usually also found below, nasally. Depending on the severity, only a part or several parts of the eye are affected by the gap formation. Sometimes the affected eyeball is a little smaller ( microphthalmia ).

The malformation can be caused in this development phase by certain chemical substances, such as a drug such as Contergan . There are also hereditary factors (including cat's eye syndrome , CHARGE syndrome , trisomy 3 , Cohen syndrome , Lenz syndrome ) and the spontaneous occurrence of the developmental disorder .

Acquired coloboma

Acquired colobomas are usually due to external violence in accidents or operations. This can lead to a split in the eyelid or iris, for example.

therapy

Coloboma as a congenital malformation of the eye can be treated in childhood. The malformation as such cannot be corrected, but symptom-related treatment based on the severity of the coloboma is possible.

A small coloboma of the iris does not necessarily require surgery . It can be concealed with a cosmetic contact lens if the iris coloboma is subjectively perceived as an aesthetic defect. A gap that has formed can be reduced or closed by means of ophthalmic suturing. If the lens is malformed or if the lens is missing, a lens implant is used. However, colobomas, which also affect the optical part of the retina, are associated with visual field defects that can neither be corrected nor reversed.

See also

Individual evidence

  1. Ulrich Drews, Pocket Atlas of Embryology, Georg Thieme Verlag - 2006 Googlebooks preview
  2. Coloboma - Symptoms, Causes, and Management. September 13, 2013. Retrieved July 15, 2016 (American English).
  3. ^ US National Library of Medicine: Coloboma. National Institutes of Health, December 1, 2016, accessed December 4, 2016 (American English).

literature

  • Keith L. Moore, Trivedi V. Persaud, Christopher Viebahn: Embryology. Stages of development, early development, organogenesis, clinic ("The developing human"). 5th edition Elsevier Verlag, Munich 2007, ISBN 978-3-437-41112-0 , pp. 518-519.
  • Th. Axenfeld (conception), H. Pau (ed.): Textbook and atlas of ophthalmology . With the collaboration of R. Sachsenweger et al., Stuttgart: Gustav Fischer Verlag, 1980, ISBN 3-437-00255-4 , p. 294.