Conjunctiva And Sclera Flashcards
What is midnit used for? What does it stand for?
-to find origin Metabolic Inflammation Degenerative Neoplasm Infection Trauma
Conjunctiva is in the inner surfaces of the eyelids and the front surface of the eyeball except
Cornea
Palpebral conjunctiva
Posterior surface of the eyelids: thicker
Bulbar conjunctiva
Anterior portion of the eyeball: thinner , goblet cells, palisades of Vogt
Fornix
Junction of the palpebral and bulbar. The plica takes the place of a fornix nasally. Also included are the caruncle, and plica semilunaris at the medial canthus
Bulbar conjunctiva is ___ attached to ___ and can become swollen or chemotic
Loosely attached to tenons capsule
Chemosis is
The swelling of the tissue that lines the eyelids and surface of the eye
Chemosis can lead to
Poor lid eye contact, desiccation (dryness) of the conjunctiva and dweller
Dellen is
Thinning of cornea that occurs from dehydration looks like blood or clear fluid build up in conjunctiva
Palpebral conjunctiva shares blood supply with
Lids
Bulbar conjunctiva’s blood supply is from
anterior ciliary arteries
Sensory innervation of conjunctiva
V1 (ophthalmic branch)
Barrier mechanism of conjunctiva
Microbiologic (pathogens), physical (curl-de-sac)
What helps protect conjunctiva
Lymphatic tissue, extra tissue and curl-de-sac
Extensive scarring an contraction of the conjunctiva may lead to
Motility restriction and diplopia
Pemphigoid
Progressive scarring and shrinkage of the conjunctiva with opacification of the cornea
Mechanical functions of the conjunctiva
Barrier, lubrication, facilitates eye movement
The conjunctiva is nutritional metabolic support to adjacent tissues like ___. Because it is __.
The sclera, cornea, iris, and ciliary body.
It is highly vascular and helps non vascularized areas
When there’s inflammation in the conjunctiva, you will see
VD of superficial vessels, mostly in periphery, away from the limbus
Inflammation of cornea, iris, and CB: will VD
Deeper vessels, towards the limbus: ciliary flush at the limbus
What contributes to the episcleral arterial circle
Both the anterior ciliary and long posterior ciliary arteries (anastomosis)
Blood flow of the conjunctiva
Oscillates rather than flows between rectus muscle insertion sites (stagnation of flow)
Stagnation of flow of the conjunctiva leads to
Greater risk of inflammatory disease in this region in the patients with autoimmune disease
Conjunctiva has the small role of maintenance of IOP
Aqueous veins drains from anterior chamber
Conjunctiva discharge is made of
Exudate, debris, mucus and tears
Serous
Allergic conjunctivitis
Mucoid
VKC and KCS (dry eyes )
Purulent
Severe acute bacterial conjunctivitis
Mucopurulent
Mild bacterial conjunctivitis and chlamydial conjunctivitis
Acute conjunctivitis
Pus and mucus
Exudate
Protein and cells
Inflammation papillae
Dilates, telangiectatic vessels: dot- like changes to enlarged tufts surrounded by edema and cells
Mild papillae
Smooth, velvety appearance
Chronic/progressive papillae
Elevates POLYGONAL, hyperemic mounds, with a central red dot (dilated capillary)
Papillae are associated with
- bacterial/ allergic reactions
- chronic blepharitis
- floppy eyelid syndrome (sleep apnea)
- SLKC ( superior limbic keratoconjunctivitis)
- contact lens wear
What are follicles
Focal lymphoid nodule with accessory vascularization, round, or oval clusters of lymphocytes like grains of rice
Small follicles are often visible where
Normal lower fornix
Clusters of enlarged, non inflammed follicles in the inf. Fornix of children and adolescents
Benign lymphoid folliculosis
What is follicular conjunctivitis: Redness and new or enlarged follicles is caused by
CHAT: chlamydia, herpes, adenovirus, toxic
Viral & toxic/irritive
Focal or diffuse dilation of the sub-epithelial plexus of conjunctival vessels
Hyperemia
Conjunctival edema caused by transudate from conjunctival capillaries. Often associated with acute allergic conjunctivitis
Chemosis
Laxity of conjunctiva, sometimes with prolapse over the inferior eyelid margin. Often associated with chronic inflammation, blepharitis and dry eye
Chalasis
The 2 mechanisms of chronic epiphora are
- interference with inferior tear meniscus
- occlusion of inferior punctum
Coagulated exudate adhered to inflamed epithelium
Pseudomembrane (inflammation of conjunctiva)
Easily peeled off
(Adenovirus infection, Steven Johnson syndrome, gonococcal conjunctivitis)
Infiltrate superficial layers of conjunctival epithelium
Membrane (inflammation of conjunctiva)
(Diphtheria, beta hemolytic streptococcus)
-cannot remove
Conjunctival scarring severity ranges from
Subepithelial fibrosis to symblepharon with eyelid distortion
Chronic inflammation in ocular surface epithelium
Keratinization
Yellow-white, amorphous subepithelial deposits in the inter palpebral zone adjacent to the limbus
Pinguecula
Pinguecula may have recurrent ___.
Inflammation and ocular irritation
Pinguecula treatment
Lubrications therapy or surgical excision
Common degenerative lesion as a result of the effects of UV radiation
Pinguecula
Strongly associated with UV exposure, dryness, inflammation, exposure to wind, dust, or other irritants
Pterygium
Upregulation of cytokines (VEGF), cellular migration and angiogenesis
Petrygium
Wing shaped fold of conjunctival and fibrovascular tissue invades the superficial cornea with destruction of bowmans layer
Pterygium
What is stocker’s line
Iron line at the head if a pterygium seen by cobalt blue light
A connective tissue composed of fibroblasts embedded in an extra cellular matrix (ECM) of collagen and elastics fibers interspersed with several types of peptidoglycans
Sclera
Opaqueness of the sclera is due to
It’s water constant and the less uniform orientation of the collagen fibers
Function of the sclera
Maintains the shape and size of the eye
Sclera is a vascular except for
The superficial vessels of the episclera and the intrascleral vascular plexus
Although the sclera is devoid of innervation it
Allows for the passage of nerves (optic and ciliary nerves )
Episclera vessels attachment to sclera
Firmly attached
A layer of dense vascular connective tissue, superimposed on the sclera and merges with the scleral stroma below
Episclera
Mechanisms of emmetropization include regulation of axial elongation via active control of
- The scleral extracellular matrix
- choroidal thickness
Jaundice is
Yellow conjunctiva and sclera secondary to accumulation of bilirubin
Jaundice can be due to
- liver, gallbladder, or pancreas disease
- infections, drugs, cancer, blood disorders, birth defects
Age elated scleral degeneration
- scleral rigidity increases
- scleral hydration decreases + mucopolysaccharide content
- subconjunctival deposition of fat gives the sclera a yellow color
- calcium plaques are visible as ovoid or rectangular zones of grayish transluncency surface
Scleritis is caused by
Immune mediated vasculitis - frequently leads to destruction of the sclera.
Treatment of scleritis
Systemic corticosteroids and immunosuppressants
Episclera this treatment
Resolves spontaneously. Topical or oral nonsteroidal anti inflammatory drugs (NSAIDS) may be prescribed for pain
Chieftain complain of Episcleritis
Ocular redness and mild tenderness, typically in only one sector of the globe. Pain worsens by palpating of the globe
Episcleritis is
Common, self limited, generally benign inflammation of the episcleral tissues. It can be diffuse or nodular
