Red Eye - PowerPoint Presentation

Slide1

Red Eye

Jahangir Sadeghi MD1391Slide2

1)

Inflammation2) InfectionWe approach to RED Eye through pathology Slide3

Inflammation is a response of tissue to a noxious stimulus . This noxious stimulus may be infectious or noninfectious

Inflammation is not synonymous with infectionSlide4

A . Exogenous causes include

1: Physical-surgical 2: Trauma 3: Thermal & Radiant energies Alkali

4:

Chemical

Acid

5: Allergic

Causes of noninfectious inflammationSlide5

B – Endogenous Causes

1) Necrosis of intra ocular tumor Ischemic Immune basis

2)

unknown cause as most cases of uveitisSlide6

Infectious causes :

1) Bacterial 2) Viral 3) Rickettsial

4)

Fungal

5)

ParasiticSlide7

Phases of Inflammation : 1)

Acute “ immediate or shock ” phase 2) Subacute phase.

“

immune

process

”

3) Chronic phase Slide8

A- Five cardinal signs : 1)

Redness 2) heat 3) Tumor or mass

4)

Pain

5)

Loss of function

Acute phase of inflammationSlide9

( Acute phase )

B- Is related to histamin relase from mast cells ( lasting from 3 to 5 hours )

and maintained by chemical mediators Slide10

1- Histamine is found in granules of mast

cell & polymorphonuclear leukocyte2) Serotonin - Is found in granules of mast cell & platelates

-

Is a vasoactive agent

3)

Kinins

4)

Plasmin –An enzyme for fibrinolysis

Histamine and chemical mediatorsSlide11

5) Complement system – consists of 8 Alpha or

Bata Globulins and one gamma GlobulinsBiologic functions (C.S)A- histamin

relase

B-

facilitation of phagocytosis of foreign protein Slide12

6) Prostaglandins – Fatty Acids Function

1- contraction of smooth muscle 2- Vasodilatation 3- platelet aggregation inhibitory action Slide13

1) Immediately , arterioles contract “

abut 5 minutes ”Then they relax and dilate from the chemical mediators2) Release of heparin by mast cells helps to prevent coagulation in blood vessels “ at the area of injury “

Phisio

pathalogy

of acute phase of an injurySlide14

3) During the early period following an injury the

leukocytes “ predominantly polymorphonucleor “ (P.M.N) stick the vessel walls and prolonged and pass through vessel walls

_

PMN are the main inflammatory cells in acute

phase

_

First line of defense

_

Start to phagocytosis and lysosomal digestion

_ When PMN cell die they liberate proteolytic

enzymes

that produce tissue necrosisSlide15

Acute phase is an exudative phase

What is exudation & Transudation Exudation is passage of protein – containing fluid and cells through opened endothelial vascular cells into surrounding tissue “ inflammatory exudate in uveitis “

Transudation

is passage of fluid through intact vessel wall into surrounding tissue .

(

so protein content is low or nil

) (

Transudation of aqueous

) Slide16

1) Serous exudate – composed of protein seen

clinically in aqueous “Flare in anterior chamber “2) Fibrinous exudate - high fibrin content in

“

Plastic

irritis

“

3)

Purulent exudate – composed of PMN and necrotic products in “

Hypopyon

“4) Sanguineous exudate – is

composed of

erythrocytes as in

“

Hyphema

“

Diffrent

type of exudateSlide17

1 – Acute inflammation2 –

Subacute inflammation3 – Chronic inflammationSlide18

1 – PMN release lysosomal

enzymes lysosomal enzymes increase capillary permeability and cause tissue destruction . So (

necrosis – recurrence and chronicity is

seen in this phase

)

2 –

Monocytes “ Macrophages “

are the second line of cellular defense in this phase

Subacute

inflammationSlide19

What is lysosomal enzymes

(including collagenase ) 1: Released by - PMN

-

MN

- Epithelial cells and kerotocytes

in corneal ulcers

2: Result in tissue destructionSlide20

MN cells arrive after PMN followed by ingrowth of capillaries – New vessels leak fluid and leukocytes “

PMN . M.N “Slide21

1) Not all infectious agents are injurious 2)

certain microbes can live within tissue without damaging their host 3) The first requirement of infectious agent is that it gain entry into the host . Principal portals of entry are natural orifices

4)

Few organism can pierce the intact skin

5)

An organism my by non pathogenic in one site but

pathogenic in another

InfectionSlide22

6) Infectious agents employ one or both of two

main pathogenic mechanisms a: invasiveness b: formation of toxins7) Bacterial toxins are two main types

a:

Exotoxin

–

produced by gram

+

b:Endotoxin – produced by gram

-Slide23

Certain strains of staph.produce a deposition of fibrin on the surface of organism , forming a capsule which protect it from phagocytosis

What is Coagulase ?Slide24

_ A viscous , polysaccharide acid is present of

Intercellular ground substance of many tissues. Many bacteria produce enzymes which hydrolyze H.A_ Consequently , ground substance of interacellular becomes fluid and bacteria and toxins diffuse throughout the tissues easily

What is

Hyaluronic Acid ?Slide25

1) They have capacity to prevent or suppress the development of local

heat – redness & swelling 2) At the microscopic level they inhibit from edema – fibrin deposition – capillary dilatation migration of leukocyte's , capillary proliferation

fibroblast proliferation etc.

Anti – inflammatory properties of

cortico

steroidsSlide26

3) Underlying cause of the disease remains

USE ENOUGH SOON ENOUGH OFTEN ENOUGH LONG ENOUGH Slide27

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