Conjunctiva
Diseases and disordersConjunctiva
Thin transparent layer, joins the eyelids with the eyeball. Composed of three parts Bulbar Palpebral FornicealHistology of conjunctiva
Epithelium Stroma (substantia propria) a- Superficial adenoid layer: b- Deep thicker fibrous tissue. Mucin secretor cells: Accessory lacrimal glands:Conjunctivitis: Inflammation of the conjunctiva
Microbial AllergicRedness F. B. sensation discharge Itching Significant pain Photophobia
Symptoms
Hyperemia
SignsDilatation of blood vessels of the conjunctiva, it is a non-specific sign and can be seen in any type of microbial or allergic inflammation.
Chemosis
Swelling of the bulbar and fornix conjunctiva due to transudation of fluid from the damaged blood vessels into the sub-conjunctiva. It is a non-specific sign.Papillae
Mosaic like multiple, translucent, hyperemic elevations of inflamed conjunctiva. Papillae are non-specific sign, composed of hyperplasia of epithelium and edema of stroma with central core of blood vessel.Causes bacterial conjunctivitis Allergic conjunctivitis Contact lens wear
Folliclesmultiple, solid, nodular elevations that push blood vessels aside. It consists of hyperplasia of lymphoid tissue within the stroma. Follicles are a more specific sign
Causes Viral Chlamydial Hypersensitivity to topical medication
MembraneOccurs in inflammation of the conjunctiva with profuse secretion. It is coagulated exudates adherent to inflamed conjunctiva. True membrane; firmly adherent to inflamed conjunctiva, e.g. diphtheria. Pseudo-membrane; loosely adherent to inflamed conjunctiva, e.g. gonococcal conjunctivitis
Subconjunctival hemorrhage ocular trauma, viral conjunctivitis or spontaneously.
Type of Discharge:Watery in viral and allergic conjunctivitis Purulent in severe bacterial conjunctivitis Muco-purulent in mild bacterial conjunctivitis Mucinous in severe allergic conjunctivitis
Regional Lymphadenopthy
(sub-mandibular and pre-auricular L.N.) May be a sign of viral, Chlamydia or gonococcal conjunctivitisLaboratory investigations
Taking smears for Grams’ and Giemsa staining Indicated in :Severe purulent conjunctivitisChronic.Ophthalmia neonatorum conjunctivitisBacterial Conjunctivitis
Most common causative bacteria are Staph. aurous, Staph. epidermidis, Strep sp. Symptoms 1-Foreign body sensation 2-Redness 3-purulent or mucopurulent discharge, morning stickiness of the eyelids Signs Hyperemic conjunctiva, muco-purulent secretion and papillary reaction Treatment Local antibiotic eye-drops and/or ointments e.g. ciprofloxacin, fucithalmic eye-drops, gentamicin ointmentGonococcal Conjunctivitis
Causative agent: Nisseria gonorrhea Affects newborn (Ophthalmia neonatorum), or young adults Severe conjunctivitis with profuse purulent discharge, eyelids swelling, chemosis and pseudo-membrane formation. The infection can rapidly spread to the cornea causing corneal ulceration and perforation within 48 hours.Management 1- Admission to the hospital 2- Topical antibiotics; e.g. gentamicin eye-drops. Initially topical antibiotics eye-drops must be given frequently (every 5 minutes) with gradually reducing the frequency of instillation. 3- Systemic antibiotics e.g. third generation cephalosporin (Cefotaxime).
Viral conjunctivitis
Most common viral infection is adenovirus Symptoms 1-Foreign body sensation 2-Redness 3-Lacrimation Signs Hyperemic conjunctiva, chemosis, sub-conjuntival hemorrhage, watery discharge, follicular reaction, and regional lymphadenopathy. Sometimes inflammation of the cornea occurs (keratitis) as multiple intraepithelial gray granular dots (punctuate epithelial keratitis).
Clinically two ocular syndromes caused by adeno-virus: 1-Pharyngoconjunctival fever; caused by sero-type 3 and 7. Typically affects children with upper respiratory tract infection. 2-Epidemic keratoconjunctivitis; caused by sero-type 8 and 19. Not associated with systemic symptoms and keratitis occurs more common. Management Self limiting disease. This is highly contagious infection, and transmission of the virus is by respiratory or ocular secretions and contaminated towels or instruments. Precautions must be taken to avoid transmission following examination of patients, by washing of hands and disinfection of ophthalmic instruments.
Chlamydia infection of the eye: 1-Trachoma 2-Adult inclusion conjunctivitis 3-Ophthalmia Neonatorum
Trachoma
Causative agent is Chlamydia trachomatis serotype A, B, and C. Leading cause of preventable blindness in the world Common in communities with poor hygiene Common fly is the main vector in transmitting the disease Affects more than 500 million people It is endemic in the Middle East regionClinical features
Presentation: the disease presented in the first decade of life, as bilateral redness, foreign body sensation and mucopurlent secretion. Follicles: There is follicular reaction especially in the upper palpebral conjunctiva, and upper limbus. Intense inflammatory reaction with papillary reaction Keratitis (inflammation of the cornea): starts with minutes gray depressions that can be stained with fluorescein [called punctate epithelial erosions (PEE)] in the upper cornea. Pannus is a sub-epithelial fibro-vascular ingrowth invading the cornea from above toward the center. After a chronic coarse active inflammation subside with scaring.Scaring: follicles in the upper palpebral conjunctiva disappear with scar formation as a stellate or horizontal lines (Arlet’s lines). Follicles in the upper limbus replaced by depressions (Herbet’s pits).Complications: scarring causes distortion of the lids as trichiasis (misdirection of the eye lashes), entropin (inward inversion of the lid). Scarring of the conjunctiva causes destruction of the accessory lacrimal glands and goblets cells, this leads to dry eye. Cicatricial trachoma predisposes to microbial keratitis
Stages of trachoma according to WHO classification:
TF; follicles TI; Intense inflammatory reaction; TS; ScaringTT; trichiasis TCO; corneal opacification
Treatment:
Local and systemic antibiotics Topical tetracycline ophthalmic ointment twice daily for 6 weeks. Systemic tetracycline or doxycycline. In young children systemic erythromycin is given. Azithromycin 20mg/kg as a single oral doze.Adult inclusion conjunctivitis Causative agent is Chlamydia trachomatis serotype D to K. It is sexually transmitted disease Typically affects young adults Presented with acute bilateral mucopurulent follicular conjunctivitis, with regional lymphadenopathy. Keratitis; Superior pannus may also occur. Treatment Local and systemic antibiotics Topical tetracycline ophthalmic ointment twice daily for 6 weeks. Systemic tetracycline or doxycycline. In pregnant women systemic erythromycin is given. Azithromycin 20mg/kg as a single oral doze.
Ophthalmia neonatorum
Causes: 1- Chemical Typically occurs within the first day after delivery, due to allergy to antiseptic eye-drops instilled in the eye of the new born by the midwife. 2- Gonococcal conjunctivitis Causative agent: Nisseria gonorrhea Short incubation period presented 1-2 days after birth. Severe conjunctivitis with profuse purulent secretion, eyelids swelling, chemosis and pseudo-membrane formation. The infection can rapidly spread to the cornea causing corneal ulceration and perforation within 48 hours. Management - Admission to the hospital - Topical antibiotics; e.g. gentamicin eye-drops. Initially topical antibiotics eye-drops must be given frequently (every 5 minutes) with gradually reducing the frequency of instillation. - Systemic antibiotics e.g. third generation cephalosporin (Cefotaxime).3- Bacterial conjunctivitis Causative agent: Staphylococcus sp., Streptococcus sp. Presented 3-5 days after birth. Red eye with muco-purulent secretion, eyelids stickiness, Management Topical antibiotics; e.g. chloramphenicol eye-drops every few hours ,fusidic 4-Viral conjunctivitis. Causative agent: Herpes simplex type II Presented 5-7 days after birth. Eyelids vesicles, red eye with watery secretion, local lymphadenopathy. Papillary conjunctivitis with no follicles because adenoid layer of the conjunctiva formed at age of 3 months. Management; topical acyclovir ointment five times per day. .
5-Inclusion conjunctivitis. Causative agent: Chlamydia trachomatis Presented 5-15 days after birth. Red eye with papillary mucopurulent conjunctivitis, and local lymphadenopathy. No follicules because adenoide layer of the conjunctiva formed at age of 3 months. Management; topical tetracycline ointment and systemic erythromycin
Allergic conjunctivitis
Symptoms: Redness of the eye, itching sensation, lacrimation and in severe cases mucous secretion. Types: Hay fever conjunctivitis; Clinical features; Transient attacks during the hay fever season Treatment; local vasoconstrictor, antihistamines and mast cells stabilizing drugs (sodium cromoglycate). Acute allergic conjunctivitis; Predisposed by contact with allergen e.g. grass, eye-drops, and cosmetics. Clinical features; sudden onset of red eye, itching sensation, lacrimation and in severe cases chemosis and swelling of the eyelids. Treatment; Resolve spontaneously after stop contact with the allergen, local vasoconstrictor, and antihistamines.Vernal keratoconjunctivitisHypersensitivity reaction (mixed anaphylactic and cell mediated)Bilateral, affect young children usually with exacerbation during hot seasons and remission during cold seasons Clinical featuresThere is papillary reaction especially in upper palpebral conjunctiva with large flat-topped papillae called cobblestone. Sometimes limbal area (junction between the cornea and the conjunctiva) becomes hyperemic and edematous with small white spots called Trantas’ dots (composed of aggregation of esoinphils)
Keratitis; In severe cases there is inflammation of the cornea (keratitis); as minutes gray depressions that can be stained with fluorescein [called punctate epithelial erosions(PEE)], corneal epithelial defect (erosion), and mucous plaque. Treatment; - Corticosteroids: In exacerbation give short coarse of topical corticosteroids. In resistant cases sub-conjunctival injection above tarsal plate (supra-tarsal) of corticosteroids (triamcinolone acetate 40mg/ml). -Topical cyclosporin in corticosteroids resistant cases -Mast cells stabilizing drugs (sodium cromoglycate), given during remission period to prevent or decrease the severity of the following attacks.
Phlyctenular keratoconjunctivitis Delayed hypersensitivity to microbial protein ( e.g. Staphylococcus exotoxin) Clinical features; small yellowish nodule in the conjunctiva near the limbus surrounded with congested blood vesssels. Treatment; short course of topical corticosteroids under cover of topical antibiotics.
Chemical burn
Acidic; causes superficial damage because these chemical coagulate proteins in the tissue and prevent further penetration of the chemical to inside the eye. Alkaline ; causes deep damage because these chemical dissolve proteins in the tissue and penetrate to inside the eye. Management: -Copious irrigation with tape water for 15-30 min espically in alkaline burn -Removal of any chemical particles from the conjunctival sac. -Use of topical antibiotics, corticosteroids and mydriatics (atropine). - Management of late complications; dry eye with lubricants eye-drops, and corneal opacity by corneal graftPinguecule
PterygiumDegenerations of the conjunctiva Pinguecula; is yellow-white elevated area in the conjunctiva adjacent to nasal or temporal limbus, caused by solar degeneration. Pterygium; is wedge shape conjunctival tissue advancing across the nasal side of the limbus into the superficial cornea. It is caused by solar degeneration.