2. - Peripheral corneal ulceration or thinning
- Affects peripheral rather than central
cornea and spreads around the margins
PATHOGENESIS :
Peripheral cornea :
- Arbitrary central limit beginning around
3.5mm. to 4.5mm. from visual axis and
extending to junction of transition between
limbus and sclera or conjunctiva
3. - Anatomically greater thickness (0.7mm.)
- Tight collagen bundle packing
- Vascular arcade originating from anterior
ciliary arteries extend up to 0.5mm into clear
cornea
- Lymphatics drain into regional lymph nodes
INFLAMMATORY MEDIATORS :
- Presence of more Langerhans cells , high
concentration of IgM and C1
- Adjacent conjunctival vessels are source of
inflammatory cells and cytokines
4. - These are involved in production of
collagenase and proteoglycanase which
cause corneal degradation
8. Ocular manifestations – hallmark :
- Epithelial loss demonstrated with
fluorescein
- Stromal inflammatory infiltration
- Thinning caused by keratolysis with or
without clear zone from limbus
9. 1. Marginal keratitis :
- Hypersensitivity reaction against
staphylococcal exotoxins and cell wall
proteins
- May also be caused by Moraxella and
Hemophilus
Antigen from tear film Antibody from vessel
Antigen antibody complexes
associated with lymphocytic infiltration
10. - Lesions are culture negative
- S.aureus is frequently isolated from lid
margins
Symptoms :
- Mild discomfort , redness and lacrimation
- May be bilateral
Signs :
- Chronic blepharitis seen
- Seen commonly at the point of contact of
eyelids with cornea(4,7,10,2’o clock)
- Inferior punctate epitheliopathy
11. - Subepithelial marginal infiltrates separated from
limbus by a clear zone associated with
conjunctival hyperemia
- Epithelial defect smaller than area of infiltrate
- Heals rapidly and recurs rapidly
- Coalescence and circumferential spread
- No AC reaction even with larger infiltrates
Treatment :
- Low dose steroids ( FML/Lotepred) QID for 1-2
weeks with topical antibiotic
12. - Blepharitis is treated
- Recurrence is treated with oral
Tetracycline course
Outcome :
- Resolution occurs in 1-4 weeks
- Residual superficial scarring and slight
thinning with mild pannus
- Iris new vessels may develop but resolves
13.
14. Moorens ulcer :
- Chronic serpiginous or Rodent ulcer
- Rare degenerative autoimmune disease
due to release of collagenolytic enzymes
- Progressive circumferential peripheral
stromal ulceration with later central spread
- Precipitating factors – Corneal insult due to
surgery or infection
- Associated systemic autoimmune disease
15. Less aggressive More aggressive
Affects elderly Young (malignant)
Unilateral Bilateral with severe pain
Responds well Systemic immunosuppression
To medical therapy needed
Pathogenesis : Ischemia due to limbal
vasculitis
16. Symptoms :
- Pain(neuralgia) , photophobia , blurred
vision
Signs :
- Peripheral ulceration involving superficial
1/3 rd stroma with variable epithelial loss
- Ulcer has undermined infiltrated whitish
overhanging leading edge
17. - Vascularization involving bed of ulcer upto
leading edge but not beyond
- Progressive circumferential and central
stromal thinning
- Limbitis present but scleritis rare
- Healing stage – thinning , vascularization
and scarring
- Iritis may occur
- Mainly diagnosis of exclusion
18. Complications :
- Severe astigmatism
- Corneal perforation following minor
trauma(spontaneous rare)
- Secondary bacterial infection
- Cataract
- Glaucoma
19. Treatment :
- Difficult as ischemia is underlying cause
- Topical steroids hourly + Antibiotic
- Topical cyclosporin
- Artificial tears
- Collagenase inhibitors – acetylcysteine
- Systemic immunosuppressants – IV MTX
- If medical treatment not useful then
conjunctival resection with
keratoepithelioplasty done to avoid
collagenases and proteoglycanases
20.
21. TERRIEN MARGINAL DEGENRATION :
- Uncommon idiopathic peripheral thinning
- Associated with scleritis and episcleritis
- 75 % - males are affected and bilateral
Symptoms :
- Usually asymptomatic
- Visual disturbance due to astigmatism
- Sometimes episodic pain and inflammation
22. Signs :
- Fine yellow white (lipid) refractile stromal
opacities with superficial vascularization
(pannus)
- Starts superiorly and spreads overall
- Separated from limbus by a clear zone
- No epithelial defect
- May look like Arcus Senilis
23. Peripheral circumferential thinning
Peripheral gutter
Outer slope shelves gradually and inner
(central)rises sharply with band of lipid
- Perforation rare(spontaneous or traumatic)
- Pseudopterygium may occur
24. Treatment :
- Spectacles
- Contact lenses
- Surgery – Crescentic or annular excision
of gutter with lamellae with full thickness
replacement
25.
26. DELLEN :
- Drying of localized area of cornea due to
pingecula or SCH
- Saucer like thinning with intact epithelium
- Fluorescein pools but does not stain
Treatment : Lubricants and treating cause
Complications : Perforation , descematocele
27.
28. SYSTEMIC AUTOIMMUNE
DISEASES:
•May precede or follow
onset of systemic features
Pathology :
•Immune complex
deposition in peripheral
cornea
•Episcleral and
conjunctival capillary
occlusion
•Secondary cytokine
release and inflammatory
cells recruitment
•Upregulation of
collagenases and
reduced inhibitors
29. - Most common – RA – 30% bilateral
- 2nd most common – Wegener
granulomatosis – ocular signs initial in 50%
- Others – PAN, relapsing polychondritis,SLE
Clinical features :
- Crescentic ulceration with epithelial defect
, thinning and stromal infiltration at limbus
- Extension into sclera seen
- Limbitis,scleritis and episcleritis seen
- No separation between ulcer and limbus
31. - Surgical – conjunctival resection with
keratoepithelioplasty
Rheumatoid paracentral ulcerative keratitis :
- Punched out centrally located lesion with
little infiltrate in a quiet eye
- Perforation occurs rapidly
Treatment :
Topical cyclosporin + Bandage contact lens +
Tissue glue application
32. Corticosteroids usage :
- Mild case of RA – Topical CS
- In GPA,Wegeners,Microscopic
polyangitis,Churg Strauss,PAN topical
corticosteroids may enhance perforation
- So cyclosporin A with systemic therapy used
Systemic steroids :
Acute - Oral prednisolone – 1mg/kg/day
If progression is present – Methyl prednisolone
pulse therapy (0.5 to 1gm.)for 3 days
33. - Severe cases(perforation chance)-
Prednisolone 100mg/day with
immunosuppressants
Immunosuppressants :
- Initial choice – cyclosporin
A(2.5mg/kg/day) if no nephrotoxicity
- GPA associated PUK with necrotizing
scleritis – cyclophosphamide + CS
- Maintenance – Oral /SC MTX
34. Biological agents :
- Anti TNF,Anti B cell monoclonal antibodies
Systemic therapy continued for 6 months to 1
year after subsiding of inflammation
35.
36. OCULAR ROSACEA :
- Common chronic idiopathic dermatosis
- Involves skin exposed to sun – face and
upper neck
- Ocular complications – 6 to 10%
- Facial telangiectasia,papule,pustule
formation and rhinophyma occur
37. Etiology :
- Multifactorial
- Vascular factors + abnormal response to
commensal skin bacteria and Demodex
follicularis mites
- H.pylori exacerbation may also be present
Symptoms :
- Irritation and lacrimation
38. Signs :
Lid – Marginal telangiectasia, posterior
blepharitis, Recurrent meibomian cyst
formation
Conjunctiva – Hyperemia(bulbar),cicatricial
conjunctivitis, conjunctival granuloma and
phlyctenules
Cornea – keratitis at inferior cornea with broad
spade shaped pannus with vessels extending
into stroma with subepithelial infiltrates at
leading edge
39. Treatment :
- Lubricants
- Lid hygiene
- Topical antibiotics ( Azithromycin E/O
QID )
- Steroids for exacerbations
Systemic therapy :
- Tetracyclines(Doxy 100mg. Once daily
for 4 weeks then 50mg.daily)
- Azathioprine for severe disease
- Retinoids may be useful
42. PELLUCID MARGINAL DEGENERATION :
- Type of corneal ectasia
- Progressive peripheral thinning mostly inferior(4
to 8’oclock)
- Bilateral and in adults
Symptoms :
Progressive blurring of vision due to astigmatism
43. Signs :
- Crescenteric 1- 2 mm. band of inferior
corneal thinning 1mm. From limbus
- Epithelium intact – cornea above thinned
area ectatic and flickered
- Myopia and against the rule astigmatism
- Fleischer ring and Vogts striae are rare
- Topography – Butterfly pattern