cornea by fazlu muhammed

1. OPTOM FASLU MUHAMMED
CORNEA

2. HERPES ZOSTER OPTHALMICUS
 Varicella zoster virus causes chicken pox(varicella )
&shingles (herpes zoster )
 HZO discribes shingles involving the dermatome
supplied by the opthalmic division of the 5 th cranial
nerve
 Mechanism of involvement :
1. Direct invasion : causing conjuctivits& keratitis
2. Secondry inflammation : Scleritis , uveitis
3. Reeactivation : causes necrosis & inflammof the
sensory ganglia leading to cornal anasthesia &
neurotropic ulcers

3. RISK OF OCULAR INVOLVEMENT
1. Hutchinson sign : invovlment of the skin suppliued
by external nasal nerve , a branch of nasocillary
nerve, supply the lip and side & root of the nose –
strong corelation with ocular involvemnt
2. Age : 6 -7 th decade
3. AIDS :
if affected in children r/o immunocomp/malignancy

4.  ACUTE SHINGLES
Skin lesions in the dermatomes , varies accrding to
age of the lesions –vesicles-> crusting-> scar
 Eye disease
1)Acute 2)Chronic
1)Acute :
a)Acute epithelial keratitis :
In 50% of cases within 2 days of onset of rashes
Resolve sponatneously
Characterised by dendritic lesions
Rx: Topical antiviral

5. b) Conjuctivitis
Follicular /pappilary
On Rx
c)Episcleritis :
Reslove spontaneously
Mild NSAIDS
d) Scleritis :
e)Nummular keratitis :
10 days after onset of rash
Characterised by fine grandular sub epithelial
depositis surrounded by halo of stromal haze

6. f) Disciform keratitis
g)Anterior uveitis
h)Monitor IOP
i)Neurological complications
CN palsies 3 ,4 6
Encephalitis

7.  CHRONIC EYE DISEASES
1) Neurotropic keratitis
2) Scleritis -scleral atrophy
3) Mucous plaque keratitis : sudden appearance
4) Lipid degenration
5) Lipid granulomata
6) Eyelid scarring-entropion /extropion

8. INTERSTICIAL KERATITIS
 Inflammtion of the corneawithout primary
involvement of the epithelim or endothelium
 Immune mediated process
 Etiology : syphillis / herpetic keartitis , cogans
syndrome
SYPHYLLITIC IK
 CONGENITAL / AQUIRED
CONGENITAL :
 Transplacentally
 Causes anterioir uveitis , IK, dislocation of the lens ,
optic atropy, retinopathy

9. AQUIRED
uveitis , IK, optic neuritis , madarosis
SYPHILITIC IK
1)Presentation:
 If congenital : 5 – 25 yrs
Anterior uveitis , b/l
 If aquired : unilateral
2)Signs :
 limbitis , deep stromal vascularization – salmon patch
apperence
 Granulaomamtous anterior uveitis
 After months the vessels become non –perfused : Ghost
vessals
 If the cornea later becomes inflammed , vessels are refilled
and bleeds
 Scarring

10.  Rx: systemic antibiotics (pencillin)
 Steroids and clyclopegics

11. PROTOZOAN KERATITIS
ACANTHAMOEBA
 Commonly found in URT
 Cystic form –highly resilent & infective in
favourable environmental condition , also produce
enzymes for tissue penetration
 Symptoms :
 Blurred vision & Severe pain out proportion to the
lesions

12.  SIGNS :
 Early : irregular epithelial surface
 Epithelial psuedodentrites
 Limbitis with stromal infiltration
 Gradual enlargement of infitrate and coalescence
to form a ring abscess
 Scleritis
 Stromal opacification and vascul
 Corneal melting

13.  INVESTIGATIONS :
1. Staining of the corneal scraping (PAS / calcofluor
white )
Gram and Gimesa
2. Cultures :
3. Others :
RX:
 Suspected if the patient do not respond well with
antibiotics
1. Debridment :
2. Topical Amoebicides : polyhexamethylene biguanide
0.02%
And/ chlorhexidien digluconate 0.02%
3. Pain control

14.  ONCHOCERCIASIS
 River blindness
1. Caused by oncecerca volvulus
2. Second most common infectious cause of
blindness
3. Sign:
 L ive microfilariae can be seen in the cornea
/aqeous /vitreous in 50 %
 Anterior Uveitis
 Punctate keratitis and sclerosing keratitis initally in
3 and 9 o clock postion , later on extending on to
the whole cornea and scarring
1. Rx: systemic Ivermectin and steroids ( for acute
inflammation )

15. XEROPHTHALMIA
 Defficency of vit . A
 Vit . A: Functions
1. Epithelial surfaces
2. Immune function
3. Retinal photorecetops
CAUSES :
1. MAL ABSR/ NUTRI
2. ALCOHOL
3. SELECTIVE DIET

16. DIAGNOSIS
 SYMPTOMS:
1. Night blindness/ nyctalopia
2. Loss of vision
CONJUCTIVA
1. XEROSIS:
Dryness in interpalpbral zone
Loss of globlet cells
Squamous metaplasia, keratinization

17. 2.BITOTS SPOTS :
Keratinised epithelium in the interp…---
cornybacterium xerosis
CORNEA
1. Lusterless- due to second xerosis
2. B/L punctate epithelial erosions epitheliad
defects
3. Keratinization
4. Corneal melting (liqufactive necrosis) –perforation

18. RETINA
Retinopathy –yellowish peripheral dots
Rx:
Kearatolamalacia –indicated severe vitm defficency –
medical emergency – risk of death
SYSYTEMIC
ORAL: 2 lkh IU
IM : 1 lakh IU
Dietary supplements

19.  Local
Lubricants
Retinoic acid – promote Healing
Corneal perforation – Sx

20. WHO Grading of Xeropthalmia
XN- Night blindness
X1-conjuctival xerosis (X1A), Bitots Spots ( X1B)
X2- corneal xerosis
X3 – corneal ulceration
X3A< 1/3 rd
X3 B > 1/3 rd
XS corneal ulcer
XF-xeropthlamic fundus