OPHTHALMOLOGY REVIEW

• History

• Past Medical History– Hipertension– Diabetes– Allergy

• Other accompanying disease

Lens

• Equatorial diameter– 6.5mm at birth– 9-10mm in late life

• AP width– 3mm at birth– 6mm at 80 yrs of age

Retina

• Layers– RPE– Rods and cones– ELM– ONL– OPL– INL– IPL– Ganglion cell layer– Nerve fiber layer– INL

MYOPIA

HYPEROPIA

ASTIGMATISM

Accomodation

• Ciliary muscle contraction– Moves ciliary muscle mass forward and

inward– Relaxes zonular tension

• Lens assume a globular shape, shortening the anterior curvature

• Lens thickening is due to change in nuclear shape

Presbyopia

• Loss of accomodative power

• Steady, is completed by age 50

• Causes:– Increased size of lens– Altered mechanical relationships– Increased stiffness of lens nucleus secondary

to changes in crystalline proteins of the fiber cytoplasm

PTERYGIUM

• Wing shaped, triangular fibrous subepithelial ongrowth of bulbar conjunctival tissue over the limbus

PATHOPHYSIOLOGY

• Strongly correlated to UV exposure• Dryness, inflammation and exposure

to wind and dust• Collagenase up-regulation and

cellular migration and angiogenesis

CLINICAL FEATURES

• Small, gray corneal opacity near the nasal limbus

• The conjunctivae overgrows the opacity and encroaches onto the cornea in a triangular fashion

• In the cornea, there is destruction of the Bowman’s layer by fibrovascular ingrowth with mild inflammatory changes

• Nearly always preceded and accompanies pingueculae

• With prevalence increasing steadily with proximity to the equator

COMPLICATIONS

• Astigmatism• Inflammation/ irritation due to

disruption of the precorneal tear film• Decrease in vision due to

involvement of the visual axis

INDICATIONS FOR EXCISION

• Cosmetic reasons• Limitation of EOMs• Progression towards the visual axis

SURGICAL TECHNIQUES

• Bare sclera• Primary conjunctival closure• Rotational flap• Conjunctival autografts• Amniotic membrane grafts• Lamellar keratoplasty

Conjunctivitis

• One of the most common nontraumatic eye complaints

• Inflammatory process that involves the conjunctiva.

• Cellular infiltration and exudation characterize conjunctivitis on a cellular level.

Classification

• Based on cause:– Viral– Bacterial– Fungal– Parasitic– Toxic– Chlamydial– Chemical– Allergic

VIRAL CONJUNCTIVITIS

Etiology

• Adenovirus is the most common cause

• Herpes simplex virus (HSV) is the most problematic.

• Less common: varicella-zoster virus (VZV), picornavirus (enterovirus 70, Coxsackie A24), poxvirus (molluscum contagiosum, vaccinia), and human immunodeficiency virus (HIV).

Signs and Symptoms

• Ocular itching

• Foreign body sensation

• Tearing

• Redness

• Photophobia

Signs and Symptoms

• Preauricular adenopathy• Epiphora• Hyperemia, chemosis, subconjunctival

hemorrhage• Follicular conjunctival reaction• Pseudomembranous or cicatricial conjunctival

reaction• Edematous and ecchymotic eyelids. • Corneal epithelial defect.

Management

• Treatment of conjunctivitis is supportive.

• Cold compresses and lubricants, such as artificial tears, for comfort.

• Topical steroids may be used for pseudomembranes or when subepithelial infiltrates impair vision

Management

• Conjunctivitis caused by HSV are treated with topical antiviral agents, including idoxuridine solution and ointment, vidarabine ointment, and trifluridine solution.

• Treatment of VZV eye disease includes oral acyclovir, 600-800 mg, 5 times daily for 7-10 days.

BACTERIAL CONJUNCTIVITIS

Etiology

• Gram-positive cocci - Staphylococcus epidermidis, Streptococcus pyogenes,Streptococcus pneumoniae

• Gram-negative cocci - Neisseria meningitidis, Moraxella lacunata

• Gram-negative rods - genus Haemophilus, family Enterobacteriaceae

• Pseudomonas aeruginosa • Chlamydia trachomatis. • Neisseria gonorrhoeae

Signs and Symptoms

• Acute onset, minimal pain, occasional pruritus, exposure history

• Chlamydial conjunctivitis: chronic onset, minimal pain level, occasional pruritus, and STD history.

Signs and Symptoms

• Preauricular adenopathy sometimes occurs; chemosis is common.

• Discharge is copious, thick and purulent.

• Conjunctival injection is moderate or marked.

Signs and Symptoms

Chamydial conjunctivitis:

• Occasional preauricular adenopathy

• Chemosis is rare.

• Minimal, seropurulent discharge

• Conjunctival injection is moderate

Management

• Antimicrobials and symptomatic therapy, including topical sulfacetamide, erythromycin, gentamicin, ciprofloxacin, or ofloxacin.

• Gonococcal conjunctivitis requires systemic treatment: norfloxacin, cefoxitin, ceftriaxone, cefotaxime, or spectinomycin.

• Treat chlamydia with tetracycline, doxycycline, azithromycin, or erythromycin

ALLERGIC CONJUNCTIVITIS

• Seasonal allergic conjunctivitis (SAC)

• Perennial allergic conjunctivitis (PAC)

• Vernal keratoconjunctivitis (VKC)

• Atopic keratoconjunctivitis (AKC)

• Giant papillary conjunctivitis (GPC)

• Seasonal and perennial allergic conjunctivitis – SAC typically have symptoms of acute

allergic conjunctivitis for a defined period of time

– In contrast, individuals with PAC may have symptoms that last the whole year

• Vernal keratoconjunctivitis – Chronic bilateral inflammation of the

conjunctiva– Associated with a personal and/or family

history of atopy.

• Atopic keratoconjunctivitis – AKC is a bilateral inflammation of conjunctiva

and eyelids, which has a strong association with atopic dermatitis.

• Giant papillary conjunctivitis – “Giant" papillae, which are typically greater

than 0.3 mm in diameter. – Immunologic reaction to a variety of foreign

bodies: contact lenses (hard and soft), ocular prostheses, extruded scleral buckles, and exposed sutures.

Signs and Symptoms

• Itching of the eyelids

• Watery discharge

• Redness

• Photophobia

• Pain

• Foreign body sensation

• Blepharospasm

Seasonal and perennial allergic conjunctivitis

– Classic signs of allergic conjunctivitis: injection of conjunctival vessels, chemosis eyelid edema.

– Milky appearance due to obscuration of superficial blood vessels by edema within the substantia propria of the conjunctiva.

Vernal keratoconjunctivitis

– Giant papillae, occur on the superior tarsal conjunctiva, assume a flattop appearance (cobblestone papillae)

– A ropy mucus discharge– Horner-Trantas dots: degenerated epithelial

cells and eosinophils. – Punctate epithelial keratopathy (PEK). – Vernal pseudogerontoxon: degenerative

lesion in peripheral cornea resembling corneal arcus.

Atopic keratoconjunctivitis

• Dry, scaly, and inflamed skin.• Meibomian gland dysfunction and keratinization. • Blepharitis, chemosis, papillary reaction• Fibrosis of conjunctiva • Punctate epithelial keratopathy,

neovascularization, stromal scarring, and possibly ulceration.

• Keratoconus, which may stem from chronic eye rubbing.

• Anterior or posterior subcapsular cataract formation

Giant papillary conjunctivitis

• Large cobblestone papillae• Mechanical ptosis of the upper lid. • 3 zones of superior tarsal conjunctiva

(Allansmith). • Soft CL: appear in zone 1 and progress toward

zone 3, while with rigid gas permeable CLexhibit a reverse pattern

• Localized irritant• Chronic bulbar conjunctival injection and

inflammation

Management

• Systemic and/or topical antihistamines

• Mast cell stabilizers

• Nonsteroidal anti-inflammatory drugs (NSAIDs)

• Corticosteroids