Corneal degenerations

eye disease

1. CORNEAL DEGENERATIONS Dr. K. Vasantha M.S., F.R.C.S. Director RIO Chennai ( Rtd )

2. Bilateral, symmetrical Mostly central cornea Non-inflammatory, hereditary disorders, little or no relationship to systemic or environmental factors Not accompanied by vascularisation Mostly AD Unilateral,asymmetric Mostly peripheral cornea D/t aging,trauma, inflammation or systemic diseases Accompanied by vascularisation Deterioration or change in a normal tissue that renders the tissue less functional Corneal dystrophies Corneal degenerations

3. Arcus senilis Bilateral-type 2 hyper- lipoproteinemia Gray/white/yellow band separated from limbus by a clear zone of 0.2-0.3 mm clear zone called lucid interval of Vogt. This may get thinned-senile furrow Diffuse central & sharp peripheral border

4. In arcus senilis there is deposition of cholesterol, cholesterol esters, neutral fats and phospholipids in the extra cellular spaces of the peripheral stroma. First appears in the inferior stroma and the posterior layers and then spreads

5. Hyperlipoproteinemia Type 2 &3 Increased β lipo proteins – Nephrotic syndromes, hypothyroidism, high cholesterol intake, obstructive jaundice, diabetic keto acidosis If it is unilateral think of carotid artery disease Also in lecithin cholesterol acyltransferase def. and Tangier disease2 Arcus juvenilis or anterior embryotoxon

6. Hudson- Stahli line : occurs in the inferior third of the cornea in old age without any pathology Fleischer’s ring : epithelial iron deposit at the base of the keratoconus Ferry’s line: corneal margin of the filtering bleb Stocker’s line : proximal to the advancing edge of the pterygium Corneal pigmentations

7. Argyrosis : if silver containing drops are used gets deposited in the DM Chalcosis : deposition of copper Chrysiasis : deposition of gold in patients with arthritis using gold compounds Topical epinephrine can cause deposition of adrenochrome , which are brown or black in color

8. Iron deposition at level of bowman’s layer Associated with previous corneal foreign body Coat’s ring

9. Vogt’s white limbal girdle White crescent like line along nasal & temporal limbus Type1-seperated from limbus by a clear zone Type 2-no clear zone between it & limbus HPE: subepithelial lesion with hyperelastosis & mild hyaline degeneration

10. Area within interpalpebral fissure is affected. Centre of band will be slightly inferior to the centre of cornea Swiss-cheese like appearance: clear circular areas within the band is seen where nerve endings perforate Bowman’s layer Calcific band keratopathy

11. Primary Band keratopathy

12. Non crystalline deposition of ca phosphate, hydroxyapatite, and calcium carbonate in Bowman’s membrane & superficial stroma starts in periphery leaving a clear zone between limbus & opacity. Involves interpalpebral area just below the centre Von Kossa stain is used to detect calcium deposit BAND KERATOPATHY

13. ASSOCIATED WITH Chronic Uveitis Pthysis bulbi Absolute glaucoma Juvenile rheumatoid arthritis Interstitial keratitis Trauma If secondary

14. Sarcoidosis, Fanconi’s syndrome, hypophosphataemia , multiple myeloma, lupus, vit.D toxicity, lung and bone disease with increased calcium, ichthyosis In gout deposition of urate crystals can be seen In primary band keratopathy (hypercalcaemia) the deposits will be intracellular In secondary it will be extracellular Treatment: chelation with EDTA (0.4%), PTK Secondary band keratopathy

15. Secondary Band Keratopathy

16. Atheromatous ulcer Sometimes in long standing opacities calcium deposits will occur. If the deposit falls off it disrupts the epithelium forming an ulcer called atheromatous ulcer

17. Unlike band keratopathy it involves deeper layers of cornea also. Seen in grossly distorted globes and leucomas Maybe associated with intraocular bone formation Atheromatous degeneration

18. Salzmann’s nodular degeneration In corneas that had been inflamed many years earlier E.g.: phlyctenular keratitis, trachoma, vernal keratitis etc., Elevated blue-grey, fibrous nodules in superficial stroma, just beneath epithelium Base of nodule maybe surrounded by iron deposition HPE: mound of dense collagenous tissue

19. Common characteristics of both Pellucid and Terrien’s are Non inflammatory Slowly progressive Epithelium and endothelium are normal Stromal thinning Bowman’s will be disrupted Defective vision due to against the rule astigmatism Marginal degenerations

20. Pellucid marginal degeneration

21. Bilateral, narrow band of thinning in periphery with normal tissue between limbus & degenerated cornea in the inferior quadrant Typical kissing birds sign with topography High astigmatism, keratoconus or keratoglobus can be seen in other members of the family Treatment – C shaped lamellar or full thickness graft Hybrid or scleral lenses Very rarely hydrops can occur Pellucid Marginal Degeneration

22. Unilateral or asymmetrically bilateral Fine, punctate stromal opacity with a lucid zone is seen in the superior cornea Lucid zone becomes superficially vascularised and can form a pseudo pterygium The thinning is parallel to limbus Lipid deposits are seen in the lower margin which is steep but no over hanging edge as in Mooren’s Terrien’s marginal degeneration

23. Spheroidal degeneration Corneal elastosis, Labrador keratopathy, climatic droplet keratopathy, Bietti nodular dystrophy etc., Predisposing factor: UV-exposure Clusters of fine, yellow, gray, amber or gold colored droplets are seen beneath epithelium of cornea Begins peripherally & advances towards the centre Dark red proteinaceous deposits are seen in the anterior stroma replacing BM

24. Type 1. bilateral without other ocular pathologies Type 2. Secondary to other ocular pathology Type 3. with conjunctival deposits either with type one or two Types of Spheroidal degeneration

25. The deposits contain tryptophan, tyrosine and other sulphur containing amino acids. Immunoflorescence techniques show presence of IgA and IgG

26. If the lesion is superficial without involvement of the Bowman’s, simple scraping or PTK can be done If it is deeper lamellar keratoplasty is done Ocular surface disorders like dry eye must be looked for as it is prevalent in these patients Treatment

27. Lipid keratopathy Can occur primarily in normal cornea Secondary to other chronic inflammations Treat the vascularisation first Keratoplasty

28. Discrete, tiny, gray/white opacities, scattered throughout deep corneal stroma -FLOUR DUST APPEARANCE HPE: lipofuscin like material-due to ageing, wear & tear Cornea farinata

29. Punctate and filamentous opacities; appear transparent and glassy on retro illumination Lesions are axial and posteriorly located Polymorphic amyloid degeneration of cornea

30. SENILE FURROW DEGN : in the lucid interval between an arcus & limbus CORNEA GUTTATA : common, bilateral, t iny dark spots on central endothelium rarely progress to Fuchs’ dystrophy HASSAL-HENLE BODIES/WARTS : localized areas of nodular thickening in peripheral cornea

31. Filamentary keratitis K.F. ring Important non degenerative lesions

32. Filamentary keratopathy

33. Seen in severe dry eye – to be treated with cyclosporine and artificial tear drops Superior limbic kerato conjunctivitis Mucus strands attached to the cornea are surrounded by epithelium. These have to be sometimes removed and anterior stromal puncture done to prevent recurrence Filamentary keratopathy

34. Deposition of copper in the Descemet’s membrane Starts in the periphery. So if a patient is referred to rule out K.F. ring one must see with a gonioscope also Seen in chronic liver damage due to Wilson’s disease Kaiser Fleischer ring

35. In Wilson’s disease it is usually starts at the age of around ten . It is also seen in primary biliary cirrhosis and familial cholestatic disease Diffuse deposits are seen in pulmonary carcinoma and multiple myeloma

36. Kaiser Fleischer ring

37. Bilateral Present at birth, with uniform thinning Familial association with keratoconus has been noticed Seen in Ehlers- Danlos also Spectacle correction will yield reasonable vision Large diameter lamellar or penetrating keratoplasty can be tried KERATOGLOBUS

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