EYELID

Question 1

What part of the body is the thinnest in the body and contains no fat?

Answer 1

Eyelid

Question 2

Where is subcutaneous aerolar layer located?

Answer 2

Found between outer skin and underlying the orbicularis

Question 3

What 2 parts contains in the orbicularis layer?

Answer 3

Palpebral portion / Orbital portion

Question 4

Palpebral portion is innervated by?

Answer 4

CN VII –> Facial nerve

Question 5

Paralysis of orbicularis will cause?

Answer 5

The lower lid to droop away from the globe –> AKA ECTROPION

Question 6

Function of Orbicularis portion?

Answer 6

to keep the eyelid closed

Question 7

Function of the palpebral portion is?

Answer 7

Spontaneous and Reflex tearing

Question 8

Palpebral portion have 2 parts, what are they?

Answer 8

Muscle of Riolan AKA pars ciliaris

Muscle of Horner AKA pars lacrimalis

Question 9

What is the function of M. of Riolan?

Answer 9

Keeps the lid margin tightly applied to the globe during eye movements
Also helps to rotate the eyelashes toward the eye when eyes are closing

Question 10

What is the gray line? and where do you find this?

Answer 10

Most anterior portion of the muscle riolan

Located between eyelash insertions and meibomian glands

Question 11

What is significant about Gray line?

Answer 11

This is the place you can go in surgically for lid repair by dividing anterior and posterior portions

Question 12

Whats the function of Muscle of horner?

Answer 12

These are the fibers that encircle the canaliculi and help to drain tears into the lacrimal sac

Question 13

Horner syndrome is?

Answer 13

Reverse ptosis of the lower eye lid

Why? coz you have lack of sympathetic innervation to the inferior tarsal muscle

Question 14

What are the characteristics of Horner syndrome?

Answer 14

Ptosis –> affected side due to paralysis of superior tarsal smooth muscle

Miosis –> affected side due to paralysis of pupillary dilator smooth muscle in the iris

Anhidrosis –> Loss of sweating on the affected side, due to loss of innervation by the sympathetic fibers

Flushed, warm dry skin –> Vasodilation of the subcutaneous arteries on the affected side coz since sympathetic doesnt work that means no vasoconstriction tone and sweat gland innervation

Reverse ptosis of the lower eye lid

Question 15

The function of Orbital septum?

Answer 15

It acts as a barrier, that restricts fat from falling down to the onto the lid margin and keeps infections localized to the anterior portion of the eyelid, away from the orbit

Question 16

Characteristics of Orbital septum/

Answer 16

Made out of dense irregular connective tissue
Continuous with periorbita and periosteum of the skull
Attached medially to the posterior lacrimal crest
Lacrimal sac is anterior to this attached, thts why protect the lacrimal sac from infection

Question 17

Periorbita

Answer 17

Loosely covers the orbital bones
Found in anterior to become the orbital septum
posterior to fuse the dura of the optic nerve

Question 18

Preseptal cellulitis is?

Answer 18

infections that occur anterior the orbital septum

Question 19

Orbital cellulitis is?

Answer 19

Infections occur posterior to the orbital septum