Introduction to Eye diseases

Hasan Mohidat MDVitreoretinal diseases and surgery,

JUST

Structures

• Eyelids• Lacrimal system• Conjunctiva• Cornea• Glaucoma• Lens• Retina• Strabismus• Trauma• Neuro ophthalmology

Upper lid

Lower lid “similer structure to upper eye lid but its shorter and less mobile”

Entropion“its interning of the eye lid toward the globe it will cause erosion in the corneal epithelium and if it left untreated

will form scars”

the cause is conjunctival scaring the scar will contract interning of the eye lid

must be corrected surgically otherwise blindness

Ectropion ”opposite to entropion the eye lid is hanging down happens in the lower lid more bcz of gravity effect most commonly due to senile changes in the eye lid tissues , or due to facial nerve palsy which will lead to loss of innervations in the orbicularis oculi muscle the complaining will be excessive lacrimation , and bcz of the closing of the eye lid is from temporal side to

the nasal side like a zipper then it will squeze the tears to the nasal side where we have lacrimal drainage system. surgical correction

Ptosis “it’s a congenital form which is the most common form”

Ptosis 3rd nerve

The right eye deviated not bcz of pathological reasons but bcz the right eye will receive Equal innervation to the left eye so when you ask the pt to look toward you using the left Eye the right eye will deviate

Hordeolum and Chalazion “infection of one of the glands in the eye lids one of them is meibomian gland”

Internal VS external

TT by topical antibiotics or surgical

Internal hordeolum bcz its infecting the Meibomian gland

When its infecting the eye lash follicles its called external hordeolum

Xanthelasma due to hyperlipidemia , or it can be just senile changes has no effects on the eye just cosmetic تجميلي so if the pt complains about it we just

excise it .

Malignancy, basal cell CA

Lacrimal system

Jones dye test

Stenosis

This represent the inferior nasal meatus

Positive test the die will go out through nose

Dacryocystogramits radio opaque technique

to assess the drainage to the inferior nasal meatus .

Probingfor tt and dx. The dr striating the eye lid by pulling laterally and upward bcz the canal is

going vertically first then lateraly

Dr said just lateraly

Acute dacryocystitis infection of the lacrimal sac due to occlusion of the nasolacrimal duct usually lower part infection which is painful and may cause fever tt with systeminc antibiotics , sometimes abscess will form

here you need to drain it once the infection subside then you have to solve the problem by a procedure called Dacryocystorhinostomy create a new opening to the lacrimal sac and the nose

The pt will present with excessive lacrimation

Congenital NLD “nasolacrimal duct” obstruction

Due to failure of canalization of the lacrimal duct the treatment is just by massage this area by the mother while feeding the baby squeezing down by the age of one year the canal will be opened

Conjunctiva

Chemosis edema of the conjunctiva most commonly due to allergic reactions

Bacterial conjunctivitis

Mild conjunctivitis tt by simple antibiotics drops “chloramphenicol” dose not affect the vision

Gonococcal conjunctivitis its STD so you have to treat the partner associated with keratitis. systemic Antibiotics usually 3rd Generation cephalosporin “ceftriaxone”

Tt by antibiotics.

Can cause blindness if left untt

Viral conjunctivitis

Conjunctivitis with subconj. hemorrhageCorneal involvement

*Usually bilateral , starts in one eye then in one or 2 days will move to the other eye , *tt is supportive , give artificial eye drops , anti-histamine , steroids to reduce the inflamation*The pt will complain from itching and watery discharge.

Chlamydial conjunctivitisTrachomaInclusion conjunctivitis

Cause : sterotypes D-K sterotypes A,B,C

mode of transmission : STD tick borne

tt: tetracycline for both , erythromycin for children

notes : most common cause of blindness worldwilde

Vernal catarrh “very common”

Moderate papillary reaction Giant papillae

Cause : allergy

treatment : steroids and antihistamine , symptomatic only

notes : also called الربيعي very common , causes PAPILLARY reaction in the , االلتهابeye

Degenerations Pterygium pinguiculum

Definition : fibrovasuclar growth

difference : apex toward the center , base is away from center vise versa

complications : cover the pupil and impair vision X (no growth on pupil)

treatment : surgical excition ( has high reoccurrence rate ) X ( no need to treat) t.t with micomycin C ( antimetabolite

notes : both may get inflamed every now and then , treat with anti-inflammatory drugs > Pterygium starts usually from the nasal side of the eye

The CorneaCornea :

> has 5 layers

> stromal layer makes 90% of the thickness

> endothelial layer :

one cell layer

functions to pump fluid from the cornea keeping it dehydrated and clear

never regenerate

number of cells per cm square :

> 3000 : starting number>1000 : risk for edema

we have critical number below which blindness happens

Myopia

Image fall in front of the retina

corrected by concave lens

hyperopia

Image fall behind the retina

corrected by convex lens

Fluorescein stain • A stain that is widely used in

ophalmology , it absorbs blue light and omits yellow and green light .

It stains :

1. water : found in the aqueous humor of the eye

2. Collagen : found in the connective tissue of the eye

> normal cornea is composed of epithelium , so no stain should appear on it

> cornea with erosions and defects allows the stain to reach the basement membrane , so it will be stained .

Corneal vascularization

May occur in :

recurrent irritationinfection intropium

Microbial keratitisEarly

Advanced

Definition : infection of the cornea

risk factor : contact lens

causes : bacterial fungal viral and protozoal

management : > scraping the eye for gram stain

> start the patient on 45 topical antibiotics

HSV(1) keratitis

Typical HSV presentation .

Typical findings in florescence stain :

> dendritic ulcer

management : acyclovir , triflordim

Arcus Senilis

Definition :

opacification on the peripheral coroners of the cornea

causes :

>Aging > hyperlipidemia

* affects the stroma

* doesn’t affect vision

KeratoconusDefinition : progressive thinning and bulging of the cornea due to weak collagen .

management :

> early in the disease ,

* collagen cross linking by riboflavin or UV light

* hard contact lenses

* Ring implantation

>late in the disease ,

* corneal graft .

Keratoplasty : قرنية زراعةNotes about the procedure :

> no need for tissue cross matching between donor and recipient .

> cornea must be tested for infections and “blood born malignances ! “

> implantation for parts “ layers” of the cornea instead of the whole cornea can be done .

LAser In situ Keratomiluesis ( LASIK)

Procedure :

> keratom is used to cut a superficial layer – flap - of the cornea , usually 100 micron layer ( thickness of the center of the cornea is 500 micron ) .

> laser is used to correct the refractive error by melting parts of the cornea

> flap is then sutured back .

Notes : for people with thin cornea we scrap the cornea directly without talking a flap away , this will cause pain for the patient and vision will be blurry for a weak . This method is called PRK (photo refractive keratectomy )

Wilson’s disease

The Lens

Phakia = natural lens

aphakia : absence of the lens

pseduphakia : presence of artificial lens

Subluxation

Cataract

Early

Advanced

Opacification of the lens that can be congenital or acquired .

Management :

* past : remove the lens and give large glasses

- glasses are called aphakik glasses .

*present : replace the lens with a thin artificial lens

- no suturing for the lens

Congenital Cataract

Phacoemulsification

Intraocular lens

Past and present

GlaucomaDefinition : progressive loss of optic neurons around the optic disc , mostly caused by increased IOP

normal IOP : 10 – 21

The Angle

Intraocular pressure

Optic nerve

Temporal retina

Horizontal raphe

Papillomacular bundle

Nasal retina

Optic nerve head

Normal Glaucomatous

In glaucoma , we have enlargement of the optic cup ( the center of the optic disc ) on the expense of the optic neurons present on the rim of the disc.

Progression of VF loss

Angle closure glaucoma

Can be caused by growth of blood vessels ! .

Neovascular glaucoma

Congenital glaucoma

Congenital glaucoma can cause Increase in the size of the eye , because the sclera is still stretchable , it can accommodate for the increased IOP , this results in what is called MEGALOCORNEA.

Treatment

• Drops: B- blockers, prostaglandin analogue, alpha2 agonists, Carbonic anhydrase inhibitors, Cholinergic agonists..

• Systemic: carbonic anhydrase inhibitors, Mannitol.

• Surgery: Trabeculectomy, Tube shunts..

Trabeculectomy

Tube shunt

Retina

Histology

vitreous

Retinal breaks

Definition : peripheral retinal pathology that is considered as a risk factor for retinal detachment .

Retinal detachment, rhegmatogenous

Definition : separation between the photoreceptors and the pigmented layer

Detachment, tractional

Fibrous tissue that grows on the retina most commonly caused by diabetic retinopathy leading to traction and detachment , tt by surgary

Vitrectomy surgery

Diabetic retinopathy

nonproliferative proliferative

No growth of new blood vessels , management is by better control of glucose levels

Growth and hemorrhage of blood vessels , management is by laser photocoagulation .

Risk factors :

> duration of diabetes ( most important)

> control of blood sugar

Laser photocoagulation

Retinal vein occlusion

Branch Central

Done by : shadi jraisat & hussam asslayem

good luck ^^