CORNEAL DYSTROPHIES

CORNEAL DYSTROPHIES

we will discuss very briefly about

corneal dystrophies. we will discuss the corneal lactasias particularly the keratoconus the learning objectives of this lecture.

we want to know and have an overview of

different corneal dystrophies

 we want to know about corneal lactasias

particularly symptoms signsdiagnosis and treatment of keratoconus

what are the corneal dystrophies

the corneal dystrophies are a group of

progressive

usually bilateral mostly genetically

determined

non-inflammatory opacifying disorders

age of onset is usually first to four

decades depending upon the type of

dystrophy

but most of the dystrophies presented in

first and second decade

 different layers of the cornea at each layer is having its own dystrophy and outermost layer is the epithelium which is stratified squamous non-keratinized epithelium

multi-layered the basal cells

are conumnular

then comes the bowman layer which is

acellular superficial layer of stroma

and stroma is a regularly arranged layer

of collagen fibers

and spacing is maintained by

proteoglycans

and desmet's membrane is a thin basement

layer of endothelium

and the endothelium is a single layer of

hexagonal cells

which cannot resonate once

they are designated

so the different layers have

corneal dystrophies and the epithelial

dystrophies

are epithelial basement membrane

dystrophy and measurement dystrophy

and different dystrophies of the

government layers

are the most important is the raised

buckler dystrophy

the stromal dystrophies are less

dystrophy which further divided into

type 1 to 3

macular dystrophies and granular

dystrophy

and in the endothelial layer the folks

endothelial dystrophy is most

important

what is the epithelial basement membrane

dystrophy

it is also known as cogn microcystic map

dot fingerprint

dystrophy onset is usually in the second

decade

and few patients develop recreate

coronal erosions

in the third decade which is very very

painful

and patient is uncomfortable and unable

to perform the day-to-day working

here you can appreciate the different

presentation of this

dystrophy dot like

figures epithelium says

fingerprints like

maps and map like editions

in epithelial basement membrane

dystrophy you can also appreciate

block-like capacities

here you can appreciate in this picture

dot glycoprostration and epithelial

microces

and the sub-epithelial map-like patterns

in the lower

figure

and the other type of epithelial

dystrophy is the amazement dystrophy it

is autosomal dominant

inheritance onset usually in the second

year of life

and in this case you can appreciate

intra epithelial cys

maximal in the central region

and the bowmen layer rhys buckler

dystrophy is the autosomal dominant

inheritance

onset is usually in early childhood with

recruited audience

you can also appreciate

polygonal opacities in bowman's layer

and the sensation of the cornea is

reduced

and usually visual impairment is there

due to scarring

at bowman's membrane level

the stromal dystrophy is the most

important is the lattice dystrophy

in this case inheritance is autosomal

dominant

presentation is in first to third decade

here you can appreciate finds padre

branching lattice lines best seen

on retro illumination.

we briefly discussed the macular

dystrophy

this type of dystrophy is least common

dystrophy

but it is visual impairment is

more serious in this case

of dystrophy there is systemic inborn

error of keratin sulfate metabolism

and inheritance is autosomal recessive

usually presentation is first decayed

with gradual

deterioration of vision

in this picture you can appreciate

macular you can see the focal poorly

delineated spots

in the anterior stroma

with irregular cordial surface may be

present

and opacification of the cornea it

increases with the passage of time

and ultimately full thickness normal

involvement.