Conj (Akers) B6 Flashcards
A thin, translucent mucous membrane that runs from the limbus, over the anterior sclera, forms a cul-de-sac at the superior and inferior fornices, and turns anteriorly to line the eyelids.
Conjunctiva
What are 3 functions of Conj?
- Ensures smooth movement of the eyelids over the globe
- Helps lubricate the eye by producing mucus and tears. (smaller volume of tears than the lacrimal gland)
- Contributes to immune system and helps prevent microbes from entering eye
Conj composition?
non-keratinized, stratified squamous and stratified columnar epithelium, with interspersed goblet cells
What produces mucin? do they reproduce?
Goblet cells, no they do not regenerate
What in the conj activates immune response?
melanocytes, T and B cell pymphocytes
What are the 3 segments of the conj?
Palpebral conjunctiva: tissue lining the eyelids
Bulbar conjunctiva: covers the sclera
Conjunctival fornix: cul-de-sac connecting palpebral and bulbar sections.
Conjunctival stem cells are scattered in the _______ throughout the conj, but are more numerous in fornix region.
Basal layer
What are the dimensions of the 4 conjunctival fornices?
Under upper lid: 8-10 mm deep Under lower lid: 8-10 mm deep Lateral: 14 mm deep Medial: 7 mm deep (lacrimal apparatus is in way medially)
At the ______________________ of the lid margin, the non keratinized squamous palpebral conj epithelium is continuous with the keratinized squamous epithelium of the epidermis of the eyelid.
mucocutaneous junction
The ______________ is translucent, allowing the sclera to show through. Its colorless unless its inflammed, then its pink eye.
Bulbar conjunctiva
Mild amount of blood trapped between bulbar conjunctiva and the underlying episclera.
Sub-conjunctival hemorrhage
What is a crescent-shaped fold of conjunctiva located at the medial canthus? what is composition and function of it?
Plicae semilunaris
Composition: Epithelium 8 to 10 cells thick contains goblet cells, stroma is highly vascularized, contains smooth muscle fiber and adipose.
Function: Allows full lateral movement of the eye without tissue stretching.
A mound of tissue that overlies the medial edge of the plica semilunaris. Contains non-keratinized epithelium and accessory lacrimal glands, also has hair follicles sebaceous and sweat glands.
Caruncle
Blood supply of conjunctiva
- Palpebral conj: palpebral arcades of the lids. Anastamose together on both sides of tarsal plate.
- Fornices: branch from the palpebral arcades extend into the fornices of the lid.
- Bulbar conj: The palpebral arcades branch into the bulbar conj (tertiary branches) and anastamose with anterior conj arteries of the anterior ciliary arteries.
Conjunctival veins parallel the arteries but are more numerous. They drain into the ___________ and ____________ veins.
Palpebral
Ophthalmic
Lateral conj lymphatics empty into the ____________.
Medial conj lymphatics empty into the ________________.
Parotid lymph node
Submandibular lymph node
Bulbar conjunctiva has sensory innervation through ________________.
long ciliary nerves
Superior palpebral conj gets innervation through ____________ and ____________________.
frontal and lacrimal branches of ophthalmic (V1)
Inferior palpebral conj gets innervation through __________ and _________
lacrimal and infraorbital branch of maxillary nerve (V2) (All sensory is from V1 and V2)
Any inflammation of the conj and can be caused by a variety of factors. Bacterial, viral, or allergic reactions.
Conjunctivitis
Below the conjunctival stroma is a thin fibrous sheet called ___________. (big pocket/fascial cavity that the eyeball sits in)
Tenon’s capsule
can inject antibiotic in sub tenons space
