Coloboma
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
![](https://upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Augenentwicklung-2.jpg/220px-Augenentwicklung-2.jpg)
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
- Collie Eye Anomaly : Coloboma in the dog breed Collie
Individual evidence
- ↑ Ulrich Drews, Pocket Atlas of Embryology, Georg Thieme Verlag - 2006 Googlebooks preview
- ↑ Coloboma - Symptoms, Causes, and Management. September 13, 2013. Retrieved July 15, 2016 (American English).
- ^ 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.