2. VIRAL KERATITIS
The most common viruses - Herpes simplex,
Herpes zoster, Adeno viruses and
Chlamydia trachomatis.
Rarely - measles, vaccinia, infectious
mononucleosis and mumps
immunoinflammatory disorders - Behcet
syndrome and Reiter syndrome may affect
the cornea.
Secondary keratitis - viruses of molluscum
contagiosum and warts(verrucae)
3. Superficial keratitis - mostly of viral.
Types of lesions produced by viral
infections of cornea:
-Punctate epithelial
erosions(multiple superficial erosions)
-Punctate epithelial
keratitis(superficial punctate keratitis)
4. HERPES SIMPLEX KERATIITIS
Etiology:
Herpes simplex virus (HSV)- DNA virus
HSV is epitheliotropic , neurotropic .
HSV two types,type-I - infection above
the waist and HSV type II below the
waist(herpes genitalis).
HSV-II can cause ocular lesions.
5. Modes of infection:
HSV-I infection - by kissing or in close
contact with a patient of herpes labialis.
HSV-II infection - through infected
genetalia of mother,STD
6. Ocular lesions of herpes simplex:
It occurs in two forms,primary and recurrent
A.primary herpes
1.skin lesions
2.conjunctiva-acute follicular conjunctivitis
3.cornea
i. Fine epithelial punctate keratitis
ii. Coarse epithelial punctate keratitis
iii. Dendritic ulcer
B. Recurrent herpes
1.Active epithelial keratitis
i. Punctate epithelial keratitis
ii. Dendritic ulcer
iii. Geographical ulcer
7. 2.Stromal keratitis
i. Disciform keratitis
ii. Diffuse stromal keratitis
3.Trophic keratitis(meta herpetic keratitis)
4.herpetic irido cyclitis
A.Primary ocular herpes
primary infection involves a non immune person
/ children under 5 years and teenagers.
8. Clinical features
Skin lesions: vesicular lesions on skin of
lids,periorbital region and lid margin(vesicular
blepharitis).
Acute follicular conjunctivitis with regional
lymphadenitis .
Keratitis: punctate or diffuse branching
epithelial keratitis
primary infection - self limiting and the virus
travels to trigeminal ganglion and
establishes the latent infection.
9. B. Recurrent ocular herpes
The virus lie dormant in the trigeminal
ganglion,periodically reactivates and causes
recurrent infection.
The predisposing stimuli -
malaria,flu,menestrual stress.emotional or
physical exhaustion.
1.Epithelial keratitis
Symptoms
redness,pain,photophobia,tearing and
decreased vision.
Signs
Three distinct patterns of epithelial keratitis
are seen
10. i.Punctate epithelial keratitis:
Initial epithelial lesions of recurrent herpes
resembles primary herpes
ii.Dendritic ulcer:
This is the pathognomic feature of
recurrent epithelial keratitis.
The ulcer is irregular,zig zag linear
branching shape.
11. The branches extend into one or more
directions and knobbed at their ends so
that a dendritic figure.
Floor stains with fluroscein and the virus
laden cells at the margin take up rose bengal
marked diminution of corneal sensation.
12. iii.Geographical ulcer:
branches of dendritic ulcer enlarge and
coalesce to form a large epithelial ulcer
with geographical or amoeboid configuration.
The use of steroids in dendritic ulcer
hastens the formation of geographical ulcer.
13. Treatment:
1.Antiviral drugs are the first choice presently
Commonly used antiviral drugs are
i. Acycloguanosine(Acyclovir)3% ointment:
5 times a day until ulcer heals and then 3
times a day for 5 days.
It is least toxic and most commonly used
antiviral drug,it penetrates intact corneal
epithelium and stroma achieving therapeutic
levels in aqueous humour.
ii. Ganciclovir(0.15% gel), 5 times a day until
ulcer heals and then 3 times a day for 5 days.
It s more toxic than acyclovir.
14. iii. Trifluoro thymidine one percent drops:
Two hourly until ulcer heals and then 4 times a
day for 5 days.
iv. Adenine arabinoside(vidarabine)3% ointment:
5 times a day until ulcer heals and then 3 times
a day for 5 days.
2.Mechanical debridement of the involved area
along with rim of surrounding healthy epithelium
with the help of sterile cotton applicator under
magnification helps by removing the virus laden
cells.
3.systemic antiviral drugs for a period of 10-21
days are increasingly being considered for
recurrent and even acute cases in the following
doses:
15. Acyclovir 400 mg p.o. tid to bid, or
Famcyclovir 250 mg p.o. bid, or
Valacyclovir500 mg p.o. bid
Non specific supportive therapy and
physical and general measures are same as
for bacterial corneal ulcer.
2.stromal keratitis
i.Disciform keratitis
It is due to delayed hypersensitivity
reaction to the HSV antigen .
Primarily there occurs endothelitis and the
endothelial damage results in disciform
corneal stromal oedema due to imbibition of
aqueous humour.
16. Signs
Focal disc shaped patch of stromal oedema
without necrosis ,usually with an intact
epithelium.
Folds in descemet’s membrane.
Keratic precipitates.
Ring of stromal infilterate(wessely immune
ring)may be present surrounding the stromal
oedema.
Corneal sensations are diminished
IOP may be raised despite only
mild anterior uveitis.
During active stage diminished corneal
sensations and keratic precipitates are the
differentiating points from other causes of
stromal oedema.
17. Treatment
Consists of diluted sterile eye drops
instilled 4-5 times a day with an antiviral
cover(acyclovir 3%) twice a day.
Steroids should be tapered over a period
of several weeks.
When disciform keratitis is present with
an infected epithelial ulcer, antiviral drugs
should be started 5-7days before the
steroids.
ii. Necrotising interstitial keratitis: caused
by active viral invasion and tissue
destruction.
Symptoms: pain, photophobia and redness.
18. Signs:
Corneal lesions include necrotic, blotchy,
cheesy white infiltrates that may lie under
the epithelial ulcer or under the intact
epithelium.
Mild iritis and keratic precipitates are usually
associated(herpetic keratouveitis)
Stromal vascularization may occur.
Treatment:
Systemic antiviral drugs for 10to21 days are
being considered in recurrent cases and in
those with associated herpetic uveitis
Keratoplasty should be deferred until the eye
has been quiet with little or no steroidal
treatment for several months.
19. 3.Metaherpetic keratitis:
It is not an active viral disease but is a
mechanical healing problem due to persistent
defects in the basement membrane of the
corneal epithelium.
Presents as an indolent linear or ovoid
epithelial defect, margin of the ulcer is grey
and thick due to heaped up epithelium.
Treatment is aimed to promote healing by use
of lubricants(artificial tears) and bandage
soft contact lens and lid
closure(tarsorrhaphy).
20. HERPES ZOSTER
OPHTHALMICUS
Acute infection of gasserian ganglion
varicella zoster virus-chicken pox in children
DNA virus ,neurotropic in nature.
Pathogenesis:
childhood - chicken pox
virus remains dormant -Gasserian ganglion
21. elderly people , depressed immunity -
reactivates
travels along branches of fifth nerve
Clinical features
Frontal nerve - frequently effected than
lacrimal ,nasociliary nerves.
50% of HZO - ocular complications
Hutchinsons rule - ocular involvement
Vescicles on side or tip of nose (cutaneous
involvement of naso ciliary nerve)
22. Lesions limited to one side of midline
Clinical phases
I.Acute- totally resolve with in few weeks
II.Chronic- persist for years
III.Relapsing- acute or chronic lesions
reappear sometimes years later.
I. Acute phase lesions
A. General features
Sudden illness- fever ,malaise, sever
neuralgic pain along course of affected
nerve.
23. B.Cutaneous lesions:
area of ditribution of the involved nerve
3-4 days of the onset of disease.
The skin is red and
Oedematous - vesicular
formation.
vesicles- pustules- crusting ulcers-
permanent pitted scars
24. active eruptive phase - 3 weeks
severe neuralgic pain - diminishes with
subsidence of eruptive phase.
C. Ocular lesions:
appear at subsidence of skin eruptions
1.Conjunctivitis - mucopurulent
conjunctivitis, acute follicular conjunctivitis
with regional lymphadenopathy.
25. 2. Zoster keratitis:
Epithelial keratitis fine or coarse punctate
epithelial keratits
micro dendritic epithelial ulcers peripheral
and stellate
tapered ends ,no bulbs in contrast to HSV
dendrites.
26. Anterior stromal infiltrates- nummular
keratitis
multiple tiny granular deposits
Disciform keratitis - 50% of cases .
3.Episcleritis , scleritis- at the onset of the
rash.
28. II.Chronic phase lesions
sequelae of acute phase- persist ten years
a)Post herpetic neuralgia - mild or moderate
pain
worsens by touch and heat.
anaesthesia with post herpetic neuralgia -
anaesthesia dolorosa.
b)Lid lesions - ptosis ,trichiasis,entropion and
notching.
c)Conjunctival lesions - chronic mucous
secreting conjunctivitis.
29. d)Corneal lesions are:
Neuroparalytic ulceration -sequelae of acute
infection , gasserian ganglion destruction.
e) Exposure keratitis - facial palsy.
f)Mucous plaque keratitis - 5% of cases.
g) Scleritis and uveitis
III.Relapsing phase lesions- nummular
keratitis,episcleritis,scleritis and secondary
glaucoma.
30. Treatment
prevent severe devestating ocular complications
,promting the healing of skin lesions
I. Systematic therapy
i. Oral antiviral drugs
Acyclovir 8OOmg 5 times a day for ten days or
Valacyclovir - 500 mg TDS
These drugs decrease the pain,curtail
vesiculation, stop viral progression and reduce
the severity of keratitis and iritis.
ii. Analgesics
first two weeks - very severe , treated by
analgesics by combination of mephanemic acid
and paracetmol or pentazocin or pethidine.
31. 3.Systemic steroids
inhibit development of post herpetic
neuralgia.
in cases developing neurological complications -
third nerve palsy and optic neuritis.
4.Cimetidine 300 mg QID for 2-3 weeks withi in 2-
3 days 0f onset reduces pain and pruritis .
5.Amitryptyline relieves depression.
II. Local therapy for skin lesions
1.antibiotic corticosteroid skin ointement or
lotion
2.No calamine lotion as it promotes crust
formation.
32. III. Local therapy for ocular lesions
1. zoster keratitis ,iridocyclitis and scleritis
i.topical steroid eye drops 4 times a day
ii.cycloplegics such as cyclopentolate(BD) or atropine
eye ointment(OD)
iii.topical acyclovir(3%) 5 times a day for 2 weeks.
2. Topical antibiotics - prevent secondary infection
3.To prevent secondary glaucoma
i. Timolol 0.5% or betaxolol 0.5% BD
ii.Acetazolamide 250mg QID.
4. mucous plakes- acetylcysteine 5-10% three times a
day.
33. 5.For persistent epithlial defects:
i.lubricating artificial tear drops
ii.bandage soft contact lens
6.For neuroparalytic corneal ulcer
Lateral tarsorraphy should be performed.
Amniotic membrane transplantation(AMT)
or conjunctival flap - non healing cases
7.Keratoplasty
for visual rehabilitation of patients with
dense scarring.
