This page covers the other types of corneal disease that have not been discussed yet.
Neurotrophic Keratopathy
This is corneal ulceration caused by denervation.
Pathology
Pathomechanism
- Loss of trigeminal innervation to cornea → intracellular oedema, loss of goblet cells → dry eye → ulceration.
Causes
- Stroke.
- Diabetes.
- Herpes.
Presentation
- Reduced corneal sensation (painless).
- Persistent epithelial defect with stromal oedema and melting.
Management
- Topical lubrication.
- Anti-collagenase agents such as tetracyclines.
- Cenegermin.
- Ocular surface protection as discussed in 'dry eye'.
Cenegermin - A topical recombinant human nerve growth factor which has shown some benefit in studies.
Exposure Keratopathy
If the cornea is exposed to the external environment for a prolonged period, it becomes dry and ulcerated.
The cornea is extremely sensitive, if you keep your eyes open now, the burning sensation is mostly from the cornea.
Pathology
Pathomechanism
- Lagophthalmos (inability to close the lids) leads to drying of the ocular surface and eventual ulceration.
Causes
- Facial Nerve (CN7) Palsy.
- Conjunctival cicatrix.
- Ectropion.
- Exophthalmos.
Presentation
- Dry gritty eye.
- Foreign body sensation.
Management
- See 'dry eye'.
Metabolic Keratopathies
This is a collection of diseases which involve characteristic deposits in the cornea.
Pathology |
Diagnostics |
Management |
|
|---|---|---|---|
Wilson’s disease |
Autosomal recessive deficiency of serum ceruloplasmin, leads to systemic deposition of copper. |
Presentation:
Characteristic Kayser–Fleischer rings - Yellow copper deposition in descemet's membrane |
Penicillamine (chelating agent) |
Band keratopathy |
Calcium deposition in Bowman's layer Typically idiopathic but is associated with hypercalcemic states. |
Often asymptomatic |
Chelation with EDTA |
Fabry disease |
X-linked lysosomal storage disorder. Caused by deficiency in alpha-galactosidase enzyme A. |
Presentation:
|
