Ocular: Conjunctiva Flashcards
What is the conjunctiva?
Thin, transparent mucous membrane that lines the inside of the eyelids and covers the sclera
What tissue makes up the conjunctiva
Stratified columnar epithelium
Function of conj
Provide protection and lubrication to the eye through production of mucous and tears
Is the conj vascularized?
YES, very
3 portion of the conj that are continuous with each other:
-palpebral
-bulbar
-fornix (curl-de-sac)
Palpebral portion of the conj lines the…
Inside of the eyelids
Bulbar part of the conj encases the…
Globes anterior sclera
Fornix (cul-de-sac) conj:
-connects palpebral and bulbar conj
Where is the most abundant site of conjunctival stem cells?
Fornix (cul-de-sac) conj
Each part of the conj has a ________ and a ________ but they are slightly different from one another
Epithelium and a stroma
The conjunctiva is continuous with:
-the cornea at the limbus
-the eyelid skin at the mucocutaneous junction (MC)
Plica semilunaris is…
Located in the medial cantonal region and is a half moon shape of bulbar conj
Plica semilunaris is a vestigial remnant of the _________ _________
Nictitating membrane
In lateral gaze, the Plica semilunaris ______ _______
Partially unfolds
The Plica semilunaris is rich in _______ ______
Goblet cells
Stroma of the Plica semilunaris contains _____ and _________ _________
Fat and non-striated muscle
Caruncle is a _________, located _________ to the Plica
Nodule, medial
What type of tissue is in the caruncle?
Nonkeratinized stratified squamous epithelium
What is located in the caruncle? (3 things)
-pliosebaceous unit
-accessory lacrimal gland tissue
-sebaceous glands
Where does caruncle get is vascularization?
Superior palpebral arteries
Caruncle sensory innervation comes from what?
Infratrochlear nerve
Conjunctival epithelium contain ________ protruding from them
Microvilli
Microvilli on the conj epithelium is covered with
Glycocalyx
Conjunctival epithelium cells a re joined by ____________ and ___________
Zonunla occludens and adherens (desmosomes)
Conjunctival epithelium contain _______ cells that secrete mucin layer of tear film
Goblet cells
What two other cells are located in the conj epithelium aside from the goblet cells?
-langerhan cells (immune surveillance)
-melanocytes (mostly close to limbus)
Conjunctival stroma is also called:
Substantia propria
Conj stroma contains:
-nerves
-blood vessels
-lymphatic vessels
Conjunctival lymphatics drain into the _______ lymphatics
Eyelid
Blood vessels surrounding the conj stroma are ____ cells and contain __________
Mast cells, histamine
Allergic conjunctivitis is involved with the…
Mast cells that contain histamine on the conjunctival stroma
Palpebral conj epithelium tissue
Stratified columnar that becomes stratified squamous near the lid margin.
Stroma of the palpebral conj contains _______ cells that secrete _____ as well as other lymphocytes
Plasma, IgA
Crypts of henle is apart of the ______
MALT
MALT
Mucosal associated lymphoid tissue
Crypts of henle:
-invaginations that trap bacteria and pathogens
-also contain goblet cells
Glands of wolfring are located on the…
Edge of tarsus on the fornix side
Lid wiper region of the palpebral conj:
-thickened specialized region contracting the eye during a blink
Lid wiper region of palpebral conj is made up of what tissue?
Stratified cuboidal or columnar epithelium with goblet cells
What muscle holds the lid wiper region of the palpebral conj in place against the globe?
Muscle of riolan
Lid wiper region of palpebral conj function:
Skims debris off the eye and spreads a fine consistent tear film over the globe with each blink
Mucocutaneous junction (MCJ) is also called:
Marx’s line
Does Mark’s line stain with dye?
YES
Marx’s line is a meeting of…
Keratinized squamous epithelium of eyelid epidermis and nonkeritinzed squamous palpebral epithelium of the conj
Where does Marx’s line occur?
Just posterior to meibomian gland openings
Bulbar conj is usually translucent and colorless UNLESS:
The blood vessel become engorged or melanocytes of epithelium
Tissue of bulbar conj epithelium:
Stratified cuboidal/columnar changing to stratified squamous near the limbus
Stroma of the bulbar conj is _________adherent to tissue below EXCEPT within ___mm of the cornea
Loosely, 3mm
Conjunctival fornix epithelium tissue
Stratified columnar
Conjunctival fornix consists of a lot of ______ and _______ cells
Goblet and stem cells
Which vitamin is required for goblet cell development?
Vitamin A
Where does goblet cell concentration increase?
It increases near the fornix and nasally
Where is the vitamin that forms goblet cells found in the eye?
The aqueous layer of the tear film
Which region is void of goblet cells?
Limbus
What happens in a vitamin A deficiency?
A decrease in the mucin layer which leads to keratin build-up on the conj called Bitot’s spots
Where are Bitot’s spots most commoly located ?
Lower temporal region where there is a lower concentration of goblet cells
4 Functions of the conj:
-antimicrobial/protective layer
-produces mucin of tear film
-permits pain-free blinks and globe movement
-palpebral conj vessels provide oxygen for cornea
What assists in pain free blinking and globe movement?
-Plica semilunaris
-lid wiper
What assists in providing the physical barrier in the conj?
Zonal occuldens and MALT
MACI is the:
Major arteriole circle of the iris
Anterior conjunctival arteries derive from what arteries?
Anterior ciliary arteries
What do Anterior conjunctival arteries supply?
The bulbar conj 2-3mm posterior to the limbus
Medial half of the eyelid lymphatics drain into:
Submandibular lymph node
Lateral half of the eyelid lymphatics drains into what lymph node?
Pre-auricular lymph node
Sub-conjunctival hemorrhage
Leak from ant conj artery or post conj artery
Conj veins course anteriorly with …
Anterior and posterior conjunctival arteries
Conjunctival veins drain into ______________ or ______________ and then drains into _________
Anterior ciliary veins or palpebral veins, superior or inferior ophthalmic vein
Autonomic parasympathetic conjunctival innervation is via ____________ _________
Pterygopalatine ganglion
Sensory innervation to superior palpebral conj:
Frontal and lacrimal branches of V1
Sensory innervation to inferior palpebral conj:
Lacrimal of V1 and infraorbital of V2
Sensory innervation to bulbar conj:
Nasociliary nerve of V1 via the long ciliary nerve
