Eyelids

Question 1

Describe skin of eyelids?

Answer 1

fat free, thin, elastic

Question 2

Describe benign and malignant growths in eyelids?

Answer 2

Both upper and lower eyelids have equal amounts of benign growths; malignant are more than 4x likely to develop in lower eyelid because the eyebrow protects upper lid from sun

Question 3

Levator Palpebrae Superioris

Answer 3

elevates upper lid; striated muscle; becomes tendinous as it enters the lid; innervated by oculomotor nerve 3

Question 4

Obicularis Oculi? Innervated by?

Answer 4

closes lids; striated voluntary muscle; helps in spreading tears and flushing away waste products; innervated by cranial nerve 7; paralysis leads to dry eye syndrome, lagopthalmus

Question 5

Muller Muscle Fibers

Answer 5

modulate position of lids of the open eye; sympathetic innervation (damage leads to droopy eye); found in both lids; lines levator internally; contraction aids in action of levator; wide eyed expression of fear

Question 6

Insertion of Levator Palpebrae Superioris

Answer 6

crease marked between the palpebral and orbital parts of eyelid

Question 7

Lack of fold means?

Answer 7

Ptosis; levator did not enter correctly

Question 8

Submuscular Areolar Tissue

Answer 8

loose connective tissue between muscle and tarsal plate; fat free

Question 9

Fibrous Layer

Answer 9

dense fibrous tissue that gives shape and firmness; known as tarsal plate; collagen more developed in upper lid than lower (eversion)

Question 10

Floppy Eyelid Syndrome

Answer 10

upper lid can be everted more than usual ; decreased tarsal elastin; genetic abnormalities of collagen or elastin
eyes burn and irritated, contact with eyelid and pillow ; poor apposition of eyelid to globe inadequate spreading of tear film; meibomian gland dysfunction

associated with sleep apnea

Question 11

Cilia

Answer 11

upper= 100-150; lower 50-75; lifespan 3-5 months; forcibly removed will grown back in 2 months (leprocy, psych disorders)

Question 12

What is chief secretion and what is it secreted by?

Answer 12

sebum; meibomian glands. forms superficial layer over precorneal tear film that slows evaporation of aqueous

Question 13

Arterial Supply

Answer 13

Facial system; orbital system

Question 14

Venous Drainage

Answer 14

superficial (pre) and deep (post)

Question 15

Lymphatic System

Answer 15

deep and superficial

Question 16

Damage of CN 7

Answer 16

causes brow to droop down on side affected

Question 17

Paralysis of CN 3

Answer 17

Ptosis of upper eyelid; complete closure of lid; frontalis works harder

Question 18

Paralysis of Sympathetic Nerve (Muller’s Muscle)

Answer 18

causes minor ptosis; associated with Horner’s syndrome; can be reversed by weak epinephrine (topical)

Question 19

What are the muscles of the eyebrow?

Answer 19

Frontalis, Obicularis Oculi, Corrugator supercilli

Question 20

Frontalis

Answer 20

Raises eyebrows; oriented radially over forehead

Question 21

Obicularis Oculi

Answer 21

found in eyelid; has orbital, palpebral, and ciliary portions ; muscle fibers oriented concentrically; sphincter action closes eyelids

Question 22

Corrugator supercili

Answer 22

pulls eyebrows together; frowning

Question 23

Bell’s phenomenom

Answer 23

Turns globe upward as lids are forcefully closed / does not occur with reflex blinking (cornea turns upward to avoid drying or becoming opaque)

Question 24

Sensory modalities stimulated during reflex blinking (3)?

Answer 24

Tactile, optic, and auditory sensations; touch, Strong lights, Approaching objects, loud noise

Question 25

Reflex blinking

Answer 25

Reflex blinking is a rapid closure movement of short duration

Question 26

What quantifies corneal reflex?

Answer 26

Aesthesiometer

Question 27

Corneal reflex diminished in?

Answer 27

contact lens wearers

Question 28

What are common reflexes that initiate reflex blinking?

Answer 28

Dazzle reflex and menace reflex

Question 29

Blephoraspasm

Answer 29

Slow sustained closure to painful stimuli An idiopathic disorder of neuromuscular control (orbicularis muscle) Results in simultaneous bilateral, symmetrical, progressive, involuntary closure of both eyes Raises IOP; Temporary relief with botulinum-A toxin

Question 30

Spontaneous Blinking

Answer 30

blinking that occurs on regular bases withput external stimuli

Question 31

Name conditions in which spontaneous blinking can change?

Answer 31

Can change secondary to level of visual activity, emotional states, and environmental conditions (Clinical point – Computer users, any activity that involvesincreased attention)

Question 32

Spontaneous Blinking in Infants?

Answer 32

low or absent

Question 33

Spontaneous Blinking in Blind

Answer 33

present; does not depend on optical stimulation

Question 34

Spontaneous Blinking motion

Answer 34

most motion occurs in upper lid; lower lid stationary; palpebral fissure closes laterally to medially flushing tears through puncta

Question 35

Rate of Spontaneous Blinking

Answer 35

Spontaneous blink rate is ≈ 15x per min; Duration of blink is 300-400 msec; Average time between blinks is 2.8 sec

Question 36

Voluntary Blinking

Answer 36

consciously initiation of closure of one eye. Most ppl blink freely with left eye

Question 37

Myokymbia and causes of aggravation?

Answer 37

fibrillary twitching ; fatigue, psychological stress, and thyrotoxicosis

Question 38

Lagophthalmos

Answer 38

incomplete closure of eyes during sleep; results in desiccation and excessive exposure of lower portions of cornea

Question 39

Ectropian

Answer 39

falling away of the lower eyelid away from globe; droopiness

Question 40

What causes ectropian?

Answer 40

weakness of obicularis

Question 41

Results of ectropian?

Answer 41

poor blink closure and epiphora

Question 42

Senile Ectropian

Answer 42

loss of tone and loss of orbital fat

Question 43

Entropian

Answer 43

turning in of eyelid

Question 44

Results of Entropian?

Answer 44

Trichiasis (turning in of eye lashes) ; trachoma (Chlamydia infection) and ocular pemphigoid; Loss of transparency or cornea (cause it to get opaque) Autoimmune reaction causes conjunctiva to shrinkScarring and shrinking

Question 45

Palpebral Fissure

Answer 45

8-11 mm wide; 27-30mm long Proptosis or large eye with shallow pits= larger fissure Recession of globe= narrow fissure

Question 46

Exophthalmos

Answer 46

Seen in Thyroid Disease Retraction of the upper eyelids causes a widening of the palpebral fissure Thyroid eye disease: Exophthalmometry measurements are remarkably similar to normal patients Vertical fissure measurements are better

Question 47

Exopthalmos Measure

Answer 47

Measurements range from 12 to 21 mm -normal subjects mean of 16 mm thyroid eye disease yield values ranging from 12 to 24 mm mean of 18 mm. Measurements of greater than 19 mm however, were found in only about 5% of normals, while 32% of those with thyroid eye disease fell above this level.