Cornea -immune mediated disorders

phlycten, chronic serpiginous ulcer, interstitial keratitis, desciform keratitis

1. Cornea syllabus- corneal pathology Opacity Edema Keratic precipitates hypopyon

2. Corneal ulcer Bacterial Viral Fungal Pasasitic

3. Immunologically mediated corneal diseases Phlylenctnular keratitis Chronic serpenginous ulcer Interstitial keratitis Disciform keratitis

4. Miscelaneous Vitamin A deficiency Exposure keratitis Neurotropic keratopathy Photophthalmia

5. Corneal degeneration dystrophy and ectatic conditions Eyebanking including eye donation and keratoplasty (basic) Basic refractive surgeries

6. sclera Scleritis Episcleritis including DD, investigation and treatment Staphyloma Blue sclera

7. Immunologically mediated corneal diseases Phlylenctnular keratitis Chronic serpenginous ulcer Interstitial keratitis Disciform keratitis

8. Phylectenular keratoconjuncitivitis Phylecten (bleb of vessels) Symptoms Phylectenulosis Endogenous T b allergen, tonsils and adenoids Limbal location Grey nodule, yellowish ulcer Infiltration Corneal margin

9. Conjunctival phylecten

10. Phylectenular keratoconjunctivitis

11. Fate of a phylecten Absorption but no scar Staphylococcol secondary bacterial infection Treatment – phlecten stage and ulcer stage Topical steroids: treatment of choice

12. Chronic serpenginous ulcer (rodent ulcer, mooren’s ulcer) Definition : mostly immunomediated , autoimmune Etiology: collagenolytic enzyme release Severe pain Start at corneal margin, spread circumferentially

13. It commences as one or more grey infiltrates, which break down, forming small ulcers that spread and sooner or later coalesce . The ulcer undermines the epithelium and superficial stromal lamellae at the advancing border, forming a whitish overhanging edge which is characteristic, while the base quickly becomes vascularized . It rarely perforates, but progresses with intermissions for months until eventually a thin nebula is formed over the whole cornea and sight is greatly diminished . Bilateral involvement with severe pain and relentless progression (‘malignant’) is more common in young adults, while a milder, usually unilateral, less painful form is seen in elderly patients.

14. Mooren’s ulcer

15. Progression of mooren’s ulcer

16. Progressive form and non-progressive form Diagnosis: PUK like, overhanging edge Diagnosis of exclusion Treatment: Peritomy topical steroids Contact lens AMT Conjunctival hooding Lamellar keratoplasty Scleral patch grafts Medical management

17. Interstitial keratitis Stromal type due to infection of allergy Measels , typhoid, syphillis , TB or idiopathic Syndromic: C ogans syndrome deafness vertigo tinnitus Syphilitic ( leutic ) interstitial keratitis: inherited and delayed Affects children and adults

18. symptoms Salmon patch

19. Radiating lines and Ground glass appearance

20. Signs Stromal haziness Neovascularisation Salmon patch : scarlet color Spontaneous resolution Cloudiness disappears Vessels obliterated (ghost vessels) Uveitis, cyclitis , choroiditis, KPs are seen Bilateral Acute stage 6 weeks

21. Diagnosis Evidence of congential syphilis Positive serological reaction

22. Treatment Penicillin Lubricants Topical steroids Cycloplegics for uveitis Later stages: corneal grafting Good prognosis

23. Disciform keratitis Seen in adults Unilateral Virus etiology Herpes ? Immune mediated response Not due to direct invasion Similar to syphilitic interstitial keratitis

24. Clinical features Central greyish disc stromal Corenal thickening DM folds Immune ring of wessliy . Corneal anaesthetic No ulcer Vision impaired Uveitis associated

25. Disciform keratitis: slit lamp view

26. Bilateral circumscribed disc of stromal keratitis showing increased corneal thickness in the slit section and keratic precipitates at the back of cornea (arrows).

27. Treatment Difficult Topical steroids Systemic antiviral