Diseases and Disorders
- Cataracts are opacities of the lens. While some are small and do not require any treatment, others may be large enough to block light and obstruct vision. Cataracts usually develop as the aging lens becomes more and more opaque, but cataracts can also form congenitally or after injury to the lens. Diabetes is also a risk factor for cataract. Cataract surgery involves the removal of the lens and insertion of an artificial intraocular lens.
- Presbyopia is the age-related loss of accommodation, which is marked by the inability of the eye to focus on nearby objects. The exact mechanism is still unknown, but age-related changes in the hardness, shape, and size of the lens have all been linked to the condition.
- Ectopia lentis is the displacement of the lens from its normal position.
- Aphakia is the absence of the lens from the eye. Aphakia can be the result of surgery or injury, or it can be congenital.
- Nuclear sclerosis is an age-related change in the density of the lens nucleus that occurs in all older animals.
Read more about this topic: Lens (anatomy)
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