Anatomy W11 - The Eye

Question 1

What is the pupil of the eye?

Answer 1

An opening where light enters the eye to reach the retina

Question 2

What is the iris of the eye?

Answer 2

A diaphragm that regulates the diameter of the pupil and controls the amount of light entering the eye.

Question 3

In health, how should the eyelid appear in relation to the iris?

Answer 3

The eyelid should cross the upper iris (no sclera seen above the iris)

Question 4

In disease i.e. hyperthyroidism, how does the eyelid appear in relation to the iris?

Answer 4

Sclera can be seen all the way around the iris giving a staring look.

Question 5

What is the lacriminal caruncle? Where is this found?

Answer 5

This is a fleshy papilla found at the medial end of the eye.

Question 6

What is sclera?

Answer 6

The white outermost coating of the eye - covered by conjunctiva (mucous membrane).

Question 7

What is conjunctivitis?

Answer 7

Red and itchy eyes caused by Infection of the conjunctiva, mucous membrane covering the eye.

Very contagious

Question 8

What is the purpose of the curvature of the hairs of the eyelashes?

Answer 8

Prevents the upper and lower eyelashes from sticking together when eyes are closed.

Question 9

Where are the follicles of the eyelashes situated on the eyelid?

Answer 9

The outer square of the eyelid.

Question 10

What is a stye?

Answer 10

An infection of the eyelash follicle

Question 11

What are meibomian glands?
What is there purpose?

Answer 11

Exocrine glands on the eyelid that produce oily secretions

Maintains tears within the eye and prevent tears spilling out.
Prevents the film of tears from evaporating

Question 12

What is a mebomian cysts?

Answer 12

Where the meibomian gland on the eyelid gets blocked by the oily secretions and forms a cyst.

Question 13

Where is the lacrimal gland situated?

Answer 13

above the lateral end of the eye

Question 14

How many ducts does the lacrimal gland have?

Answer 14

Many - into the teens

Question 15

Where do tears from the lacrimal gland drain into?

Answer 15

The conjunctival sack (sack between the front of the eyelid and the eye)

Question 16

What is the lacrimal punstum?

Answer 16

An opening to the lacrimal canaliculus ducts on the upper and lower eyelid facing into the tears

Question 17

Describe the course of excess tears from the conjunctival sack.

Answer 17

Tears enter the lacrimal canaliculus via the lacrimal punstrum.

From the canaliculus the tears enter the lacrimal sac

The lacrimal sac then enters a canal in the bone called the nasolacrimal duct

The nasolacrimal duct opens up into the inferior meatus of the nasal cavity.

Tears drain from the nose

Question 18

What can happen in trauma to the medial end of the eye?

Answer 18

Damage to the lacrimal canaliculus which creates a fistula where tears can escape into the surrounding structures.

Question 19

What is the purpose of the blink reflex?

Answer 19

Ensures that there is a film of tears covering the front of the eye and that the cornea is always moist.

Question 20

List pathology of the eyelid.

Answer 20

Stye

Meibomian cyst

Cyst of moll

Question 21

What is a cyst of moll?

Answer 21

Where there is a blockage of the apocrine sweat gland of moll.

Question 22

How do you differentiate between a meibomian cyst and a cyst of moll?

Answer 22

Cyst of moll appears like a watery bag

Meibomain gland appears as if its deeper within the tissues and NOT watery looking

Question 23

What lymph nodes will be enlarged in infection i.e. stye of the eyelids?

Answer 23

The parotid lymph nodes