Corneal degeneration

corneal degeneration

1. Corneal degeneration Dr.Rakshya Basnet 1 st year resident NAMS,LEI

2. contents Introduction Classification Peripheral corneal degenerations Central/ diffuse corneal degenerations Summary 2

3. Introduction deterioration and decrease in function aging, inflammation, or environmental insult broad spectrum of ocular abnormalities

4. 4 Features Degeneration Dystrophy Onset Presents later in life, associated with aging Present early in life, hereditary Laterality Unilateral Bilateral; May be asymmetric Bilateral & symmetric Family history Uncommon Common Vascularization Common Uncommon Location often peripherally located Centrally located Progression Progression can be very slow or rapid Progression usually slow

5. Classification No any exact classification A . According to location 1. central corneal degeneration 2.peripheral corneal degeneration B .According to ETIOLOGY 1.Involutional corneal degeneration 2.Noninvolutional corneal degeneration

6. C .According to corneal layers 1.Epithelial& subepithelial degenerations 2.Stromal degenerations 3.Endothelial degenerations

7. Classification Peripheral degenerations Corneal arcus White limbal girdle of Vogt Idiopathic furrow degeneration Post irradiation thinning Terrien’s marginal degeneration Furrow degeneration associated with systemic disease Central or diffuse degenerations Iron Lines Coat’s White Ring Lipid Degeneration Amyloid Degeneration Spheroid Degeneration/Climatic Droplet Keratopathy, keratinoid Degeneration Band Keratopathy Salzmann’s Nodular Degeneration Corneal Keloid

8. Classification Epithelial and sub epithelial degenerations

9. COAT’S WHITE RING

10. STROMAL DEGENERATION

11. SALZMANN NODULES IN PARACENTRAL CORNEA LIPID KERATOPATHY SECONDARY TO CORNEAL VASCULARISATION AMYLOID DEGENERATION CORNEAL KELOID

12. CORNEA FARINATA VOGT LIMBAL GIRDLE TYPE 2 CROCODILE SHAGREEN

13. TERRIEN MARGINAL DEGENERATION

14. Endothelial degenerations Iridocorneal endothelial syndrome Peripheral corneal guttae Melanin pigmentation IRIDOCORNEAL ENDOTHELIAL SYNDROME

15. Depending on etiology: a)Age related: Arcus senilis , Vogt’s white limble girdle Hassel- Henle bodies b) Pathological Degeneration: Fatty degeneration Hyaline degeneration Amyloidosis Calcific Degeneration Salzmann’s nodular degeneration Terrien’s marginal degeneration Pellucid marginal degeneration

16. A.Peripheral corneal degenerations

17. 1.Arcus senilis ( gerontoxon,arcus lipoides ) most common peripheral corneal degenerations

18. Band is wider in vertical than horizontal meridian A lucid interval is present between arcus and limbus This clear is about 0.3 mm wide, known as clear interval of vogt

19. 19 Prevalence- increase with age Incidence; - 60% in 50-60 years -100% in >80 years Men >women. Prevalence increase -postmenopausal period Black males have the highest incidence Arcus is almost always bilateral

20. 20 Histopathology Lipid is first deposited at Descemet's membrane and subsequently at Bowman's layer Stromal accumulations of -cholesterol esters -triglycerides -phospholipids Vascular in origin( Lipid material leaks from limbal capillaries, but central flow is limited

21. Systemic association: may be associated with dyslipidemia in under 50 years (arcus juvenilis ) Young patients who have arcus also have an increased risk for type IIa dyslipoproteinemia but a decreased risk for type IV(type 2&3) Occasionally congenital anomaly involving only a sector of peripheral cornea

22. Clinical significance < 40 years - increased risk of coronary artery disease and should be evaluated for hyperlipoproteinemia Diseases causing a rise in β- lipoproteins (nephrotic syndrome, hypothyroidism, increased cholesterol intake, obstructive jaundice, and diabetic ketoacidosis) lecithin cholesterol acyltransferase (LCAT) deficiency&tangier dz. Unilateral – carotid artery occlusion 22

23. 2.VOGT'S WHITE LIMBAL GIRDLE

24. Limbal Girdle (of Vogt) Type 1 Type I

25. VOGT'S WHITE LIMBAL GIRDLE Type I mild, early form of calcific band keratopathy chalklike opacities & scattered clear holes like swiss cheese Separated from sclera by peripheral clear zone called lucid interval degenerative change of anterior limiting membrane

26. Type 2 Type 2

27. VOGT'S WHITE LIMBAL GIRDLE Type II more common type white flecklike needlelike deposits lacks a peripheral clear zone between the arc and the limbus consists of fine, white radial lines located nasally more often than temporally. common in >45yrs,female Incidence increase with age -55% at 40-60 years

28. Histopathology Lesion is subepithelial and may have overlying epithelial atrophy Destruction and calcification of Bowman's layer (type 1) Epithelial elastotic degeneration (type 2) 28

29. 3.Senile corneal furrow degeneration Thinning of cornea in older peple in lucid interval of corneal arcus No tendency to perforate epithelium is intact Rare, true thinning with no inflammation, vascularization, or induced corneal astigmatism

30. 4.Furrow degeneration associated with systemic disease Focal or extensive ring type epithelial defect & sterile ulceration near limbus Accompany systemic dz. -rheumatoid arthritis - wegner’s granulomatosis -polyarteritis nodosa - relapsing polychondritis -SLE -collagen vascular disease

31. 5.Post irradiation thinning Non-inflammatory corneal excavation at limbus May occur after high local doses of B-radiation

32. 6.Terrien marginal degeneration: Terrien disease is an uncommon idiopathic slowly progressive thinning of peripheral cornea

33. Signs Begins superiorly,spreads circumferentially, rarely central cornea or inferior limbus Central wall is steep & peripheral wall slopes gradually Epithelium remains intact,& fine vascular pannus traverses area of stromal thinning Rupture in Descemet membrane can result in interlamellar fluid or even corneal cyst Perforation may rarely occur either spontaneously or following blunt trauma

34. Begins superonasally Fine punctate opacities in the anterior stroma Superficial vascularization Gutter forms between the opacity and limbus Stroma progressively thins Overlying epithelium remains intact 34

35. types 35 quiescent More common Older patients Asymptomatic Inflammatory Younger age Recurrent inflammation( episcleritis , scleritis )

36. Gradual visual deterioration occurs as a result of increasing corneal astigmatism Fuchs superficial marginal keratitis ( children young adults)

37. Histopathology Fibrillar degeneration of collagen Epithelium may be normal, thick, or thinned Bowman's layer is fragmented or absent Breaks in Descemet's membrane may be seen in thinned area 37

38. treatment large astigmatism impending perforation perforation lamellar or eccentric penetrating grafts 38

39. B.Central or diffuse degeneration

40. 1.Iron lines Chronic abnormalities of tear flow Hudson- stahli line: Normal aging Ferry’s line: Adjacent to filtering bleb Stocker’s line: Head of pterygium Fleischer’s ring: Base of Keratoconus

41. 2.Coats’ White Ring Small corneal opacity usually located in an area that previously harbored foreignbody

42. Coats’ White Ring <1 mm ring,circle or oval granular ring in s/ l,grey -white dots Represent iron containing fibrotic remnants of metallic FB The condition causes no symptoms & require no therapy

43. 3.Lipid degeneration primary secondary More common Occurs in vascularized cornea No prior history of: Trauma Family history of similar conditions Corneal vascularization No known disorders of lipid metabolism 43

44. Lipid degeneration Accumulation of yellow or cream colored crystalline material in corneal stroma which may be thick or thin Lipid keratopathy may be peripheral, central, or diffuse

45. Increased vascular permeability of limbal vessels Release of fatty material into the stroma from dying cells cholesterol, triglycerides, and phospholipids (extracellular space) 45

46. treatment Only If – For cosmesis and decrease vision Argon laser treatment with or without fluorescein photodynamic therapy with verteporfin Subconjunctival & topical bevacizumab

47. 4.Spheroidal degeneration Climatic droplet keratopathy Bietti's nodular corneal degeneration Labrador keratopathy Corneal elastosis Fisherman's keratitis Keratinoid corneal degeneration Chronic actinic keratopathy Eskimo’s corneal degeneration Proteinaceous corneal degeneration 47

48. Clear to yellow-gold spherules oily appearing are seen in subepithelium,bowman layer or superficial stroma 0.1 to 0.4 mm. 48

49. 49

50. Etiologies Ultraviolet radiation Microtrauma (sand, dust, wind, and drying) Type 1 ,3 Secondary degeneration is caused by multiple disease entities Associated with corneal neovascularization 50

51. Clinical grading Grade I – fine shiny droplets  present only peripherally without symptoms Grade II – central cornea is involved: vision ≥ 20/100 (6/30) Grade III – there are large corneal nodules: vision ≤ 20/200 (6/60). 51

52. pathogenesis Secreted by corneal and conjunctival fibroblasts Interaction between UV light and plasma proteins within stroma has been proposed to result in abnormal deposits 52

53. treatment Aphakic/ pseudophakic /clear lens ---excimer laser PTK cataractous condition a)cataract extraction with or without addressing opacity b) combined penetrating keratoplasty &cataract extraction c) combined lamellar keratoplasty &cataract extraction d)PTK

54. 5.Salzmann's nodular degeneration Superficial stromal opacitie s pannus Unilateral/ bilateral Female>male 54 Elevated Blue–grey nodular lesions Round or elongated Separated by clear zone

55. Etiologies Idiopathic corneal inflammatory disease, especially meibomian gland dysfunction Vernal keratoconjunctivitis Interstitial keratitis Contact lens wear Dry eye keratoconus 55

56. Histopathology Dense collagen plaques with hyalinization are located between epithelium and Bowman's layer Bowman's layer is absent under lesion Overlying epithelium may be atrophic or absent 56

57. treatment Lubrication – epithelial erosions Superficial keratectomy Lamellar or penetrating keratoplasty 57

58. 6.calcific Band keratopathy Deposition of calcium salts in the Bowman layer, epithelial basement membrane and anterior stroma 58

59. 59 Gray  white and chalky Begins at corneal periphery in 3 and 9 o’clock positions Centrally in cases of chronic ocular inflammation Periphery- sharply demarcated edge separated from limbus by a lucent zone Lucent holes are scattered throughout the opacity and represent penetrating corneal nerves

60. etiology Ocular Chronic ocular disease esp. inflammatory Silicone oil in anterior chamber Chronic exposure to mercurial vapors or mercurial preservatives Others Age-related Metabolic- hypercalcemia -elevated serum phosphous level Hereditary 60

61. Histopathology Fine basophilic granules (first at the level of Bowman's layer) Calcium deposits (intra/ extracellular) Hyaline-like material is deposited in subepithelial tissue around calcific depositions 61

62. investigations Serum calcium Phosphorus Uric acid Renal function measurements Parathyroid hormone (PTH) Angiotensin-converting enzyme (ACE) 62

63. treatment Topical EDTA 0.05 molar concentration after removal of epithelium PTK 63

64. 7.Corneal keloids White nodules  may extend deep into stroma Appear following trauma, surgery, or inflammatory processes 64

65. Histopathology Fibroblastic proliferation( myofibroblast ) intermixed with hyalinized collagen bundles Bowman's layer may be fragmented or absent 65

66. CROCODILE SHAGREEN Mosaic pattern resembling cobblestone or crocodile skin Usually bilateral Gray to white ‘cracked ice’ opacities with central lucent zones 66

67. 67 Anterior  May be seen as a senile change  K eratoconus patients with hard contact lenses  T rauma, band keratopathy, hypotony , juvenile X-linked megalocornea Posterior  A ge-related degeneration

68. CORNEA FARINATA Incidental finding Asymptomatic Very fine, dust-like dots (white or gray)  central stroma (just anterior to Descemet's membrane) idiopathic 68

69. Dellen / Fuchs’ dimples Saucer-like depressions in corneal surface Commonly adjacent to elevated areas May last only 24 to 48 hours Most commonly in temporal peripheral cornea (adjacent to a paralimbal elevation) 69

70. Cornea verticillata Lysosomal deposits in epithelium ( amiodarone ) Whorl- like pattern Other drugs- chloroquine, chlormazipine, indomethacin Usually dose not result in reduction of vision 70

71. summary Secondary deterioration or deposition in cornea, distinct from dystrophies Occurs in later life Dose not reduce visual acquity Not inherited May be age-related ( white limbal girdle, arcus senilis , crocodile shagreen , cornea farinata ) May be post inflammatory ( Salzmann nodular degeneration, corneal keloid, lipid keratopathy, calcific band keratopathy) Idiopathic (furrow degeneration, Terrien marginal degeneration) 71

72. references Krachmer , Mannis , Holland. Cornea- fundamentals, diagnosis and management. 2 nd edition . Vol 1 AAO. External disease and cornea. 2013-2014 Kanski Clinical ophthalmology. 8th edition Albert and jacobiec’s principles and practice of ophthalmology. 3 rd edition . Vol 1. 72