Lens dislocation

Classification according to ICD-10
H27.1	Dislocation of the lens
ICD-10 online (WHO version 2019)

Lens dislocation in humans: The lens is dislocated downwards. The normally invisible ciliary body fibers are visible above.

Lens dislocation in a cat. The lens can be seen as a whitish structure in the lower third of the eye.

The Linsenluxation or ectopia of the lens is a shift ( ectopia ) of the crystalline lens in the anterior chamber or into the vitreous cavity . This can be done partially ( subluxatio lentis ) or completely.

Emergence

In the event of a traumatic lens dislocation, the lens leaves its original place due to the impact of force. If the dermis tears , it can slip under the conjunctiva . After such trauma, there is usually blood in the eye - often associated with secondary glaucoma.

Lens dislocation can also occur spontaneously in large eyes with high myopia , advanced cataracts or a tumor in the ciliary body .

Congenital lens dislocation ( Latin : Ektopia lentis congenita ) usually occurs on both sides. They occur because the zonular fibers are too weak to hold the lens in place. This is the case with Marfan syndrome and Ehlers-Danlos syndrome , as well as with some hereditary bone malformations ( chondrodysplasia punctata ). Lens dislocation also occurs very early in Weill-Marchesani syndrome , homocystinuria or Walker-Dyson syndrome . See also ectopia lentis syndrome .

Symptoms

A slight, incomplete dislocation can remain symptom-free. However, higher astigmatism is the rule. In the case of larger shifts, the patient notices double monocular images that do not disappear even when the other eye is closed.

diagnosis

The lens is reduced in size and rounded due to the lack of tension in the zonular fibers. It is no longer centered in relation to the optical axis and the center of the pupil. In syndromes (Marfan or Marchesani) it may be displaced upwardly, in primary Zonulainsuffizienz (particularly Pseudoexfoliation ) rather downward. In the absence of zonular fibers z. B. through trauma (particularly typical cow tail injuries) there are tremors (phakodonesis). If the lens is completely luxated, there is an aphakic state with hyperopia (with normal eyeball length between 10 and 16 dioptres). The lens can then be found in the vitreous space , more rarely in the anterior chamber.

therapy

In the event of complications or in the event of unsatisfactory correction options using glasses or contact lenses, the lens is removed and replaced with an artificial one. However, this only works if the ectopia is not very pronounced. In the case of larger ectopias, after the entire lens has been removed, an artificial lens must be sewn in (sclera-fixed IOL) or iris-assisted enclave.

Complications

More frequent complications are the deterioration of eyesight and secondary glaucoma , with complete dislocation of the lens into the vitreous space there is a risk of retinal detachment.

Lens dislocation in animals

Lens dislocation is more common in some dog breeds. This is especially true for terriers .

Individual evidence

1. ↑ A. Burk, R. Burk .: Checklist ophthalmology. 4th edition. Syndromes, p. 521.
2. ↑ Kirk N. Gelatt (Ed.): Veterinary Ophthalmology. 3. Edition. Lippincott, Williams & Wilkins, 1999, ISBN 0-683-30076-8 .
3. ^ Simon M. Petersen-Jones: Conditions of the Lens. In: Proceedings of the 28th World Congress of the World Small Animal Veterinary Association. 2003. (online at: vin.com )

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !