Cornea

1. DISEASES OF THE CORNEA

2. Viral keratitis
 Herpes simplex keratitis
 Herpes Zoster keratitis
 Adenoviral keratitis

3. Herpes simplex virus
 DNA Virus
 Infection is common upto 90% of the population- most
of it is subclinical
 Humans are the only natural reservoirs
 Source of infection –
Direct contact with the lesions,
By salivary droplets
Fomites
By asymptomatic virus shedding carriers

4.  HSV-1 causes infection over face,lips and
eyes (mucocutaneous distribution of
trigeminal nerve)
 HSV-2 causes genital herpes
 Infection can be
- Primary
- Recurrent

5. HSV infection
 Congenital ocular herpes
- skin vesicles
- eye ds
- microencephalopathy
 Neonatal HSV keratitis
- 2 days to 2 weeks
 Primary ocular herpes
 Recurrent ocular herpes

6. Primary infection
 Occurs in early childhood
 Uncommon during first 6 months
 Transmission through droplet infection or
direct innoculation
 May be subclinical or fever,malaise and
URTI

7. VIRAL KERATITIS
HERPES SIMPLEX KERATITIS
Primary

Vesicular blepharitis
 Follicular conjunctivitis
 Keratitis Punctate
keratitis
Dendritic ulcer

8. Recurrent infection
 36% at 5 yrs
 63% at 20 years
 Activated by various trigger factors
- fever
- surgery
- systemic illness
- immunosupression etc

9. RECURRENT
HERPES SIMPLEX KERATITIS

10. PUNCTATE EPITHELIAL KERATITIS
 Fine or coarse
superficial punctate
lesions

11. DENDRITIC ULCER
FLOURESCEIN STAIN ROSE BENGAL STAIN
Ulcer –irregular,zigzag linear
branching-knobbed at the end

12. Geographic ulcer
-Geographical or amoeboid
configuration

13.  A,B-PEK
 C,D-Dendritic ulcer
 E,F-Geographical ulcer
 G,H-Disciform keratitis

14. TREATMENT
 Topical antivirals Acyclovir eye oint. 3%
Ganciclovir gel 0.15%
Triflurothymidine drops 1%
Vidarabine oint. 3%
 Cycloplegics
 Debridement of ulcer edges
 Systemic Antivirals Acyclovir 400mg tid/bd
Valacyclovir 500 mg bd
 Supportive measures
 Topical steroids ×××
HERPES SIMPLEX
EPITHELIAL KERATITIS

15.  Recurrent form- 25% of ocular herpes
 Delayed hypersensitivity reaction to HSV
antigen
 Stromal inflammation
+
Endothelial damage
corneal edema, KP’s
Descemets folds
corneal sensations
IOP +/_
 Topical steroids + antivirals
 Supportive measures
HERPES SIMPLEX STROMAL KERATITIS
Disciform Stromal endothelitis

16. DISCIFORM ENDOTHELITIS

17.  Active viral invasion
+
Tissue destruction
 Necrotic cheesy white infiltrates
 Mild iritis,KP’s(herpetic keratouveitis)
 Stromal vascularization
 Treatment topical steroids
antivirals
cycloplegics
HERPES SIMPLEX STROMAL KERATITIS
STROMAL NECROTIC KERATITIS

18. Metaherpetic keratitis /
Neurotrophic epithelial keratitis
 Occurs in patient with previous HSV
epithelial disease
 Due to impared corneal innervation
 Nonhealing sterile ulceration
 Round ,oval ulcers with grey thickenned
rolled up margins
 Complication – scarring , neovascularization,
necrosis , perforation, 2̊ bacterial infection

19. Metaherpetic keratitis / Neurotrophic
epithelial keratitis

20. Treatment
 Bandage soft contact lens
 Topical antibiotics
 Tear substitutes
 PK
 Lid closure (tarsorrhaphy)

21. HERPES ZOSTER OPHTHALMICUS
 Varicella-zoster virus
 Latency - Gasserian ganglion
 Ophthalmic div. of 5th nerve
 50% have ocular lesions
 Unilateral
 Systemic features
 Cutaneous lesions
 Ocular lesions

22.  Seen more in older age group - >75yrs
 Systemic – fever , malaise and eruptions
preceded by sever neuralgic pain
 Ocular manifestations are uncommon

23.  Ocular lesions-Acute phase
Lids Keratitis
Conjunctivitis SPK
Episcleritis & Scleritis Dendritic
Iridocyclitis Nummular
Secondary glaucoma Disciform
Acute retinal necrosis
Motor nerve palsies
Optic neuritis
Encephalitis

24.  A,B-PEK
 C,D-
microdendritic
epithelial ulcer
 E,F-nummular
keratitis
 G,H-disciform
keratitis

25. NUMMULAR KERATITIS

26. Ocular lesions-chronic
 Neurotrophic keratitis
 Scleritis-scleral atrophy
 Mucous plaque keratitis
 Lipid degeneration
 Lipid granulomata
 Eyelid scarring-entropion/extropion

27. TREATMENT OF HZO
SYSTEMIC THERAPY
 Oral antivirals Acyclovir -
800mg x10days
Valciclovir
 Analgesics
 Systemic steroids
 Amitryptyline
 Cimetidine
LOCAL THERAPY
Ocular lesions
Topical acyclovir
Topical steroids
Cycloplegics
Anti glaucoma drugs
Artificial tears
Tarsorrhaphy
Keratoplasty

28. Protozoal kerititis
 Acanthamoeba
 Microsporidia

29. ACANTHAMOEBA KERATITIS
Free lying amoeba soil, sewage, air
fresh, well, sea water
Ocular infection CL wearers using home made saline
Swimming in contaminated water
Mild trauma
Opportunistic infection
Orthokeratology

30. Life cycle
 2 stages
- Trophozoit stage
- Cyst stage - dormant

31.  Symptoms:
- foreign body sensation
- photophobia
- severe pain

32. ACANTHAMOEBA KERATITIS
SEVERE PAIN disproportional to signs
SIGNS
Epithelial stippling with
microcystic edema
Dendritiform appearance of
epithelium
Radial Keratoneuritis
Ring infiltrate

33. Stromal infection – overlying epithelium may
be intact
Stromal neovascularization is never seen even
in sever and longstanding cases
Scleritis

34. ACANTHAMOEBA
CYSTS KERATITIS

35. ACANTHAMOEBA KERATITIS
Diagnosis Treatment
 High index of suspicion
 KOH wet mount
 Calcofluor white stain
 Culture on E.coli enriched
non nutrient agar
 Confocal microscopy
 PCR of corneal biopsy
specimens
 Neomycin drops 1%
 Propamidine isethionate0.1%
drops
 Polyhexamethyl biguanide
0.02% drops
 Chlorhexidine 0.02%
 Penetrating keratoplasty

36. Fungal keratitis
 Most common organism is Aspergillus
 Infections are more common when there is
high humidity
 Incidence increased in recent years d/t
injudicious use of antibiotics & steroids

37. Classification
 Filamentous
1. Septate
- Nonpigmented – Fusarium
Aspergillus
Penicillium
- Pigmented - Curvularia
Alternaria
2. Nonseptate
Rhizopus
 Yeast
Candida

38. FUNGAL (MYCOTIC)
CORNEAL ULCERS
 Etiology Trauma with organic matter
Injury with animal tail
Systemic/ local immune suppresion
 Causative agent Aspergillus , Fusarium
Candida , Cryptococcus
Curvularia, Alternaria
 Indolent course
 Symptom – foreign body sensation , photophobia , blurred
vision and discharge

39. SIGNS MORE THAN
SYMPTOMS
SIGNS
Soft creamy raised exudates
Dry looking
Feathery margins
Satellite lesions
Sterile Immune ring of
Wesseley
Hypopyon +/-
Endothelial plaque
Posterior abscess

44. DIAGNOSIS TREATMENT
 History Organic
matter
 Typical clinical picture
 Corneal scrapings
KOH wet mount
Gram, Giemsa staining
Calcoflour white
Culture on SDA
 Topical antifungals
Natamycin 5%
Itraconazole 1%
Fluconazole 0.2%
Amphotericin B 0.1-0.2%
 Intracameral &
intracorneal/intrastromal
voriconazole
 Systemic antifungals
 Cycloplegics
 Anti inflammatory drugs
 Therapeutic PK in unresponsive
cases

45. THANK YOU!