viral corneal ulcer

short presentation of viral corneal ulcers from textbook of A.K.Khurana Ophthalmology
by myself Dr.shanmugasundaram 2014 batch in KFMSR coimbatore

1. VIRAL CORNEAL ULCER Dr.Shanmuga sundaram Ref.A.K.Khurana of Ophthalmology

2. Common viral infections Includes Herpes simplex virus (HSV) Herpes zoster ophthalmicus Adeno virus keratitis

3. HERPES SIMPLEX KERATITIS Extremely common Constitute herpetic keratoconjunctivitis and iritis ETIOLOGY:- Herpes simplex virus- - DNA virus

4. HSV types :-  HSV - I – above waist  HSV – II – below waist Mode of infection :- HSV – I – acquired by kissing or close contact with herpes labialis patient HSV – II – transmitted to eyes of neonate from affected genitalia

5. 0ccular lesions of herpes simplex Primary herpes - skin lesions - acute follicular conjunctivitis - cornea - fine epithelial punctate keratitis - coarse epithelial punctate keratitis - dendritic ulcer

6. B. Recurrent herpes 1.active epithelial keratitis - punctate epithelial keratitis - dendritic ulcer - geographical ulcer 2.stromal keratitis - disciform keratitis - diffuse stromal necrotic keratitis 3.trophic keratitis 4.herpetic iridicyclitis

7. Primary occular herpes Non-immune person Typically occurs in children of age 6 months to 5 years and teenagers CLINICAL FEATURES 1.systemic features Mild fever , malaise , non suppurative lymphadenopathy

8. 2.Skin lesions Vesicular lesions over face , lips , periorbital region and lid margins 3.Occular lesions - acute follicular conjunctivitis - keratits (coarse punctate or diffuse branching epithelial keratitis )

9. Recurrent occular herpes occurs due to periodical reactivation and replication of virus in trigeminal ganglion Predisposing stimuli - fever , malaria , flu - exposure to UV rays - general ill health , mild trauma - steriod and immunosuppresent administration

10. 1.Epithelial keratits SYMPTOMS redness , pain , photophobia , tearing and decreased vision SIGNS three dinstinctive patterns 1. punctate epithelial keratitis - initial epithelial lesion - fine or coarse superficial punctate lesion

11. 2. dendritic ulcer - typical lesion - irregular , zig zag linear branching shape - branches knobbed at ends

12. 3.Geographical ulcer branches of dendritic ulcer enlarges and coalesces to form ‘ amoeboid ‘ or ‘geographical’ configuration steroid use in dendritic ulcer also lead to geographical ulcer

13. TREATMENT A. specific treatment 1.antiviral drugs - Acycloguanosine (Acyclovir) 3% ointment 5 times a day for 14-15 days - Ganciclovir (0.5% gel) 5 times a day untill ulcer heals and then 3 times a day for 5 days - Triflurothymidine - Adenine arabinoside ( vidarabine )

14. 2.mechanical debridement removal of virus laden cells along with a rim of surrounding healthy epithelium 3.systemic antiviral drugs for a period of 10-21 days - acyclovir 400mg p.o tid to bid - famcyclovir 250mg - valacyclovir 500mg p.o bid

15. 2.Stromal keratitis a.disciform keratitis pathogenesis:- - delayed hypersensitivity reaction to HSV antigen - primarily endothelitis occurs - endothelial damege leads to disciform corneal stromal oedema

16. SYMPTOMS:- - Photophobia , mild to moderate occular discomfort , reduction in visual acuity SIGNS:- focal disc shaped patch of stromal oedema folds in descemet’s membrane keratic precipitates ring of stromal infiltrate ( wessely immune ring) Dinminished corneal sensations IOP may be raised

17. TREATMENT:- - diluted steroid eye drops instilled for 4-5 times a day with an antiviral cover twice a day - non specific and supportive treatment b. stromal necrotic keratitis :- caused by active viral invasion and tissue destruction symptoms:- pain , photophobia , redness

18. signs :- 1. corneal lesion include necrotic ,blotchy , cheesy white infiltrates 2. mild iritis & keratic precipitates Treatment:- - systemic antiviral drugs - keratoplasty

19. 3.Metaherpatic keratitis Not an active viral disease Mechanical healing problem due to persistent defect in basement membrane Occurs at a site of previous herpetic ulcer Clinical features:- indolent linear or ovoid epithelial defect margins-grey and thickened Treatment:- aimed to promote healing by use of lubricants , bandage soft contact lens and lid closure

20. HERPES ZOSTER OPHTHALMICUS acute infection of gasserian ganglion of fifth nerve by varicella zoster virus ETIOLOGY:- - varicella zoster virus PATHOGENESIS:- infection manifest as chicken pox and the child develops immunity virus remains in sensory ganglion of trigeminal nerve

21. diminished immmunity reactivation and replication of dormant virus virus then travels down along the branches of ophthalmic division of trigeminal nerve causes cutaneous and occular lesions

22. CLINICAL FEATURES:- - frontal nerve is more affected - occular complications - Hutchinson’s rule occular involvement is frequent , if vesicles where present over side or tip of the nose - lesions are strictly limited to one side of the head

23. CLINICAL PHASES:- 1. Acute phase lesions 2. Chronic phase lesions 3. Relapsing phase lesions 1.ACUTE PHASE LESIONS A. general features:- fever , malaise , severe neurologic pain B. cutaneous lesions:- area of distribution is area where the affected nerve distributed - red and oedematous (mimicking erysipelas), followed by vesicular formation - pustules  crusted ulcers  permanent pitted scars - last for 3 weeks - severe neuralgic pain

24. C. Occular lesions:-  conjunctivitis – mucopurulent with petechial heamorrhages or acute follicular with regional lymphadenopathy  zoster keratitis fine or coarse punctate epithelial keratitis – followed by micro dentritic keratitis

25. Nummular keratitis tiny multiple granular deposits surrounded by halo of stromal haze heal- nummular scar Disciform keratitis preceded by nummular keratitis

26.  episcleritis and scleritis  Iridocyclitis  acute retinal necrosis  secondary glaucoma  anterior segment necrosis and phthisis bulbi D. associated neurological complications - motor nerve palsies - optic neuritis - encephalitis

27. 2. CHRONIC PHASE LESIONS  post-herpetic neuralgia persistent pain even after subsidence of eruptive phase of zoster pain : mild to moderate , worsens at night , aggrevated by touch and heat aneasthesia dolorosa : aneasthesia of skin associated with continued postherpetic neuralgia  lid lesions – ptosis , trichiasis , entropian and notching

28.  conjunctival lesions – mucuos secreting conjunctivitis  corneal lesions - neuroparalytic ulceration - exposure keratitis - mucous plaque keratitis sudden development of elevated mucous plaque stains brilliantly with rose bengal  scleritis and uveitis

29. 3.RELAPSING PHASE LESIONS recurs even after 10 years of acute phase include nummular keratitis , mucous plaque keratitis , episcleritis , scleritis , secondary glaucoma TREATMENT aimed at preventing severe devasting ocular complications and promoting rapid healing of skin lesions resulting in scarring of the nerves and postherpetic neuralgia

30. 1.Systemic therapy Oral antiviral drugs started immediately after onset of rash * Acyclovir 800 mg 5 times a day – 10 days or * valaciclovir 500 mg TDS  Analgesics combination of mephanic acid and paracetamol or pentazocin or pethidine

31. Systemic steroids apear to inhibit postherpetic neuralgia when given in high doses consider also the complications of high dose steroids Cimetidine – 300 mg QID for 2-3 wks starting within 48-72 hrs of onset – to reduce pain Amitriptyline – releive accompanying depression

32. 2.Local theraphy FOR SKIN LESIONS:-  antibiotic-corticosteroid skin ointment or lotions : 3 times a day till skin lesion heals  No calamine lotion : as it promotes crust formation FOR OCCULAR LESIONS:-  for zoster keratitis , iridocyclitis , scleritis * topical steroid eye drops - 4 times * cycloplegics – cyclopentaloate , atropine * topical acyclovir

33. Topical antibiotics to prevent secondaary infections For secondary glaucoma timolol , betaxolol , accetazolamide 250 mg QID For mucous plaques – topical mucolytics – accetyl cysteine 3 times a day for persistent epithelial defects * lubricating artificial tear drops * bandage soft contact lens

34. 3.Surgical treatment Lateral tarsorrhaphy Amniotic membrane transplantation tissue adhesive with bandage contact lens keratoplasty

35. PROTOZOAL KERATITIS ACANTHAMOEBA KERATITIS Etiology:- causative organism- acanthamoeba castellani mode of infection - contact lens wearers using home made saline - mild trauma associated with contaminated vegetables - oppurtunistic infection

36. Clinical features  Symptoms foreign body , mild to moderate pain , watering , photophobia , blepharospasm , blurred vision Signs - epithelial lesions * epithelial roughening and ridges * pseudodendritis * epithelial and subepithelial curvilinear opacities

37. - stromal lesions * radial keratoneuritis * patchy and satellite stromal infiltrates * ring infiltrates * ring abscess - limbal and scleral lesions * limbitis * scleritis

38. Differential diagnosis 1.viral keratitis 2.fungal keratitis 3.suppurative keratitis Diagnosis:- difficult and usually made out by exclusion with strong suspicion of non responsive patients  confocal microscopy – allows direct visualisation of cyst

39. Laboratory diagnosis:- - KOH mount – reliable for experienced hands - calcofluor white stain – bright apple green - lactophenol cotton blue stained film - culture on non nutrient agar – show trophozoites within 48 hours - PCR – amoebic DNA - corneal biopsy

40. treatment Topical anti amoebic agents - diamidines - biguanides - aminoglycosides , imidazoles - multiple drug theraphy - propamidine or hexamidine + PHMB - chlorhexidine + neomycin - oral ketoconazole 200 mg BID - long term prophylactic treatment with PHMB twice a day for 1 year - penetrating keratoplasty