The adenoid layer of the conjunctiva develops after 3-4 months of life. It is most developed in fornices.
The fibrous layer of the conjunctiva is very thin in tarsal conjunctiva & it contains vessels & nerves of the conjunctiva..
The mucin secretory glands are crypts of Henle present in the tarsal conjunctiva & glands of Manz present in limbal conjunctiva, apart from the goblet cells, which are most dense in the inferonasal part of the conjunctiva..
The accessory lacrimal glands are glands of Krause present in subconjunctival CT of fornix, 42 in upper & 8 in lower & glands of Wolfring along upper border of upper tarsus & loewr border of lower tarsus..
Plica semilunaris is a vestigeal structure which represents the nictitating membrane(or the third eyelid) of lower animals..
The anterior conjunctival arteries are the branches of anterior ciliary arteries.
The circumcorneal zone of the conjunctiva is supplied by the long ciliary nerves..
The lymphatic drainage of the conjunctiva is preauricular LN(lateral side) & submandibular(medial side).
Hyperaemia in conjunctivitis is maximum in fornices & minimum in limbus.
Follicles are minute lymph follicles with accessory vascularization in the adenoid layer of the conjunctiva that are most prominent in the inferior forniceal conjunctiva..
Papillae are essentially vascular structures that have been invaded by inflammatory cells which are most prominent in the upper palpebral conjunctiva..0.3-1 mm d size are micropapillae, while more than 1 mm d are giant papillae...
The most common causes of chronic blepharoconjunctivitis are staphylococcal infection & seborrhoea.
The triple-S syndrome consists of Staphylococcus, seborrhoea & sicca..
The indications for corticosteroids in chronic staphylococcal blepharoconjunctivitis are papillary conjunctivitis, toxic epitheliopathy, marginal keratitis & phlyctenulosis...
The most common organism causing acute simple conjunctivitis is staphylococcus epidermidis followed by staphylococcus aureus...
The most common organism causing acute purulent conjunctivitis in adults is gonococcus...
The most common organism causing chronic catarrhal conjunctivitis is staphylococcus aureus...
Common causes of pseudomembrane are adenoviral, vernal, streptococcal & gonococcal conjunctivitis...
The commonest cause of membranous conjunctivitis is corynebacterium diphtheriae.. & rarely virulent type of streptococcus haemolyticus...
The common organisms causing subconjunctival haemorrhage are picorna virus & adenovirus and pneumococcus & haemophilus spp.
preauricular lymphadenopathy is seen in viral & chlamydial infections, but rarely in bacterial infections...
The organism causing red eye is haemophilus influenzae(Koch-Weeks bacillus)...
The organism causing angular conjunctivitis is moraxella lacunate (Morax-Axenfeld bacillus)...
In ligneous conjunctivitis, the membrane is cast off, but recurs, Pathology
is not known.
The virus causing acute haemorrhagic conjunctivitis( epidemic haemorrhagic conjunctivitis, Apollo conjunctivitis) is enterovirus 70(picorna virus).
Epidemic keratoconjunctivitis(EKC) is caused by adenovirus types 8 & 19 & pharyngoconjunctival fever is caused by adenovirus types 3 & 7.
EKC PCF
Age any children
Systemic symptoms -- +++
Keratitis 80% 30%
Newcastle conjunctivitis is derived from contact with diseased owls...
Adult inclusion conjunctivitis(swimming pool conjunctivitis) is caused by chlamydia trachomatis serotypes D to K, the diagnostic is Halbersteadter-Prowazek bodies, basophilic cytoplasmic inclusion bodies in conjunctival scrapings...
Inclusion Viral
Incubation 4-19 days 3-7 days
Age young adults all ages
Systemic findings genitourinary respiratory
Discharge mucopurulent watery
Course chronic self-limiting
Adenopathy ++ +++
Follicles +++ +++
bulbar & limbal ++ --
Keratitis upper corneal diffuse corneal
epithelial & early-epithelial
subepithelial late-subepithelial
Cytology inclusion bodies mononuclear cells
polymorphs
Response to tetracycline + --
Response to steroids -- +
Trachoma(Egyptian ophthalmia)
It is the second most commoncause of blindness & the most common cause of preventable blindess in the world...
It is caused by chlamydia trachomatis serotypes A, B, Ba & C..., while serotypes D-K are associated with paratrachoma(oculogenital chlamydial disease)
Incubation period is 5-21 days...
Follicles are mostly seen in the upper conjunctiva & fornix as..
a) it covers more cornea
b)warmth
c) chlamydia are dormant in the tarsal plate...
Follicles on bulbar conjunctiva are pathognomonic of trachoma..
The characterisitics of follicles in trachoma to differentiate from other follicular conjunctivitis are:
a) presence of Leber cells, large multinucleated cells in central part of the follicle
b) signs of necrosis
c) follicle may assume size upto 5 mm
Arlt's line is a linear scar present in sulcus subtarsalis at the junction of lower 1/3 & upper 2/3..
Herbert follicles are follicles present in the limbal area, while Herbert pits are oval or circular pitted scars left after healing of Herbert follicles in the limbal area...
In pannus , the vessels lie b/w epithelium & Bowman's membrane..
Class 1(Blinding trachoma)
Class 2(Non-blinding trachoma)
Class 3(Paratrachoma)
WHO classification:
FISTO
Trachomatous inflammation- Follicular(TF)- atleast 5/more follicles, each 0.5 mm or more in d, must be present on the upper tarsal conjunctiva..
Trachomatous inflammation- Intense(TI)- inflammatory thickening of the upper tarsal conjunctiva must obsure more than half of the normal deep tarsal vessels..
Trachomatous Scarring(TS)- scarring in the tarsal conjunctiva..
Trachomatous Trichiasis(TT)- at least one eyelash must rub the eyeball/evidence of recent removal of inturned eyelashes..
Corneal Opacity(CO)- at least part of pupil margin must be blurred when seen through the opacity..
Ophthalmia neonatorum
Time of presentation:
Chemical- 4-6 hours
Gonococcal- 2-4 days
Chlamydia- after 7 days, 5-14 days
Other bacteria- 3-5 days
HSV II- 5-7 days
The discharge is purulent in gonococcal conjunctivitis, which is also the most common one associated with corneal perforation...
Allergic conjunctivitis
Hay fever conjunctivitis is associated with allergic rhinitis, Seasonal allergic conjunctivitis is associated with graass pollens allergy & Perennial allergic conjunctivitis is associated with house dust & mite...
Vernal heratoconjunctivitis(Spring catarrh):
It is considered to be a type 1 hypersensitivity reaction to some exogenous allergen..
Commonly seen in 4-20 years boys...
More common in summer....warm weather conjunctivitis...
Stringy(ropy) discharge is the characteristic...
Itching accentuates in warm humid atmosphere, more common in the palpebral form...
The characteristics of the palpebral form are cobble-stone or pavement fashioned arrangement of hard, flat-topped papillae, the epithelium overlying is thickened which gives bluish milky white hue...
Horner-Tranta's dots are white dots consisting of eosinophils & epithelial debris along the limbus seen in the bulbar form...
Punctate epithelial keratitis of Togby is the most common form of corneal involvement, involves upper cornea in the palpebral form, pseudogerontoxon resembles arcus senilis, is c/b a classical 'cupid's bow' outline in a previously inflamed segment, is also characterisitic...
pH of tears is alkaline in spring catarrh...
Sodium cromoglycate is most useful in those patients with atopy...
It is associated with keratoconus...
Giant papillary conjunctivitis is associated with soft hydrophilic contact lens
Phlyctenular conjunctivitis
It is type 4 hypersensitivity response to endogenous microbial proteins...
Mostly implicated are tuberculous proteins, staphylococcal proteins & proteins of Moraxella axenfeld bacillus
It is seen in 3-15 years girls...
Parinaud's oculoglandular syndrome consists of
a) unilateral granulomatous conjunctivitis(nodular elevations surrounded by follicles)
b) preauricular lymphadenopathy
c) fever
Common causes are tuberculosis, syphilis, tularemia, cat-scratch disease & LGV...
Strong sunlight, dust & wind are considered as etiological factors...
There is elastotic degeneration of collagen fibres of the substantia propria of conjunctiva, coupled with deposition of amorphous hyaline material in the substance of the conjunctiva...
It is more common on nasal side as UV rays are reflected from nose to eye on the nasal side...
It is considered to be a precursor of pterygium...
Pterygium
Neoplastic change can occur in the form of epithelioma, fibrosarcoma or malignant melanoma...
Recurrence after surgical excision is 30-50%...
McReynold's operation is for recurrent pterygium consisting of transplantation of the pterygium in the lower fornix...
Stocker's line is a deposit of iron in the corneal epithelium anterior to the advancing head of pterygium...
Concretions are accumulation of inspissated mucus & dead epithelial cell debris into the conjunctival depressions called loop of Henle...
Yellow discolouration of the conjunctiva is seen in jaundice, malaria & yellow fever...
In conjunctival epithelial melanosis , brownish pigmentation is most marked at the limbus & around the proliferating branches of the anterior ciliary nerves as they enter the sclera... no treatment is required...
In subepithelial melanosis, pigmentation looks bluish-black sa it is under epithelium.. It can be an isolated congenital anomaly- congenital melanosis oculi or associated with an ipsilateral hyperpigmentation of the skin of the face in the ditribution of the 1st & 2nd divisions of the trigeminal nerve- oculodermal melanosis or the naevus of Ota.
Dermoids are most frequently located at the limbus...
Lipodermoids are most commonly located at the limbus or outer canthus..
Fibroma are usually in the lower fornix, while papilloma at inner canthus, fornices or limbus....
Squamous cell carcinoma occurs most commonly at limbus or the lid margin..
Other ocular anomalies are microphthalmos, anophthalmos, tilted disc, optic nerve hypoplasia, macular hypoplasia & strabismus..
Mucus Fishing syndrome:
excess mucus production --> patient tries to remove the mucus --> traumatizes the conjunctival epithelium --> further increase in mucus secretion --> vicious cycle...
The most frequent underlying disease that initiates the cycle of mucus fishing is keratoconjunctivitis sicca...
The characteristic traumatic conjunctival lesions are situated over the caruncle, plica, nasal & inferior bulbar conjunctiva & inferior tarsal conjunctiva...
Floppy eyelid syndrome:
A condition typically affecting obese men in whom a rubbery tarsus & loose upper eyelid everts during sleep & exposes the upper tarsal conjunctiva & cornea to trauma...
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