Flashcards in Fundamentals Vol. 3 Deck (35)
How many tarsal meibomian gland orifices are located in the upper eyelid? Lower eyelid?
Upper eyelid - 30 to 40 Lower eyelid - 20 to 30
Where is the marginal arterial arcades of the eyelids located?
3 mm from the eyelid margin
Where does the pretarsal portion of the venous system of the eyelid drain? Posttarsal system?
Pretarsal- internal and external jugular veins Posttarsal - cavernous sinus
Where do the medial group of eyelid lymphatic vessels drain? Lateral group?
Medial groups- Submandibular lymph nodes Lateral group - Preauricular lymph nodes
What type of epithelium covers the caruncle?
Nonkeratinized, stratified squamous epithelium
What does the caruncle contain?
What does the epithelium of the plica semiluminaris contain?
What does the stroma of the plica semiluminaris contain?
Fat and nonstriated muscle
What structure divides the main lacrimal gland into two parts?
What are the two lobes of the lacrimal gland?
Orbital and palpebral lobe
How many ducts drain into the conjunctival fornix from the main lacrimal gland?
Where do the ducts from the main lacrimal gland drain in the conjunctival fornix?
Approx. 5 mm above the superior margin of the tarsus
On what lobe the main lacrimal gland is biopsy typically performed?
Orbital lobe (in order to spare the drainage ducts of the lacrimal gland)
What are the 2 main type of cells located within the lacrimal glands?
1. Acinar cells 2. Myoepithelial cells
Which type of cells line the lumen of the lacrimal glands?
Acinar cells (surrounded by myoepithelial cells)
What artery supplies the main lacrimal gland?
Lacrimal artery (branch of ophthalmic artery)
What is the sensory innervation of the lacrimal gland?
Lacrimal nerve (CN V1)
What is the average diameter of the lacrimal puncta?
Where is the inferior lacrimal punctum located?
6.5 mm from the medial canthus
Where is the superior lacrimal punctum located?
6.0 mm from the medial cantus
What type of epithelium lines the lacrimal puncta and canaliculi?
Stratified squamous, nonkeratinized epithelium
Where does epithelium of the lacrimal drainage system separate into 2 layers?
Near the lacrimal sac
What are the 2 layers of the epithelium of the lacrimal sac?
1. Superficial columnar layer 2. Deep, flattened cell layer
What are the 3 portions of the conjunctiva?
1. Palpebral 2. Fornical 3. Bulbar
What is the blood supply to the bulbar conjunctiva?
Anterior ciliary arteries
Where is the vascular watershed of the conjunctiva located?
Approx. 3 to 4 mm from the limbus
Where are the goblet cells of the conjunctiva concentrated?
Inferior and medial portions of the conjunctiva (esp. near the caruncle)
Where on the conjunctiva are goblet cells absent?
Limbal region of the conjunctiva
What is the anterior attachment of Tenon capsule?
Intramuscular septum (3 mm posterior to limbus)