OPHTHALMOLOGY REVIEW. History Past Medical History –Hipertension –Diabetes –Allergy Other...
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Transcript of OPHTHALMOLOGY REVIEW. History Past Medical History –Hipertension –Diabetes –Allergy Other...
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