periorbital region board Flashcards
What is analogous to the levator palpebrae superioris aponeurotica in the lower eyelid?
Capsulopalpebral fascia
What is the cause of senile ptosis?
Attenuation of the levator aponeurosis.
What is the cause of classic congenital ptosis?
Inadequate/nonexistent levator function
What is the most appropriate procedure for congenital ptosis?
Frontalis sling
In senile ptosis, what happens to the supratarsal crease?
The crease becomes cephalically displaced because of adhesion between the levator aponeurosis and dermis. The
superior crease moves with attenuation of the aponeurosis.
What is the classic treatment of senile ptosis?
Levator advancement/reinsertion
What is the most common cause of postsurgical lower ectropion?
The combination of lower eyelid laxity with scarring/traction on the capsulopalpebral fascia-septum interface
What is the preferred treatment of lower eyelid ectropion?
Canthoplasty with capsulopalpebral spacer graft (AlloDerm, autologous dermis, palate mucosa, etc).
What is the most commonly injured muscle in a blowout fracture?
Inferior oblique muscle, the only extraocular muscle to insert into bone directly
Where is the apex of the brow?
The lateral limbus of the eye in forward gaze.
What is considered an abnormal Schirmer’s test?
Less than 10 mm
What does correction of ptosis in one eye do in a bilateral case?
Correction will make the noncorrected side more ptotic, due to dual innervation—Hering’s law
How much of the eyelid can be sacrificed and primarily closed?
Up to 25% total lid loss can be primarily closed
What nerve travels in the floor of the orbit?
Infraorbital nerve
What muscles are responsible for medial brow retraction?
Corrugator, depressor supercili, and, to lesser extent, orbicularis oculi.
How many fat compartments are in the upper lid?
Two
How many fat components are in the lower eyelid?
Three
What separates the lower eyelid central and nasal fat pads?
Arcuate extension of Lockwood’s ligament.
What nerve opens the eye?
Cranial nerve III
What nerve closes the eye?
Cranial nerve VII
What findings make up Horner syndrome?
Blepharoptosis, pupil miosis, and facial anhidrosis
What is lagophthalmos?
Inability to close the eye
What is chemosis?
Edema of the conjunctiva
What is the mucous spot test?
A subjective measure of dry eye, absence of a film layer on the eye surface indicating chronic dry eye.
What nerve can be found adjacent to the sentinel vein?
Temporal branch of the facial nerve
Should the lacrimal gland be excised if ptotic?
No
What reconstructive technique is typically used for a central (full-thickness) upper eyelid with 50% defect?
Semicircular skin/muscle flap rotation or Tenzel flap
What flap is commonly used for total lower eyelid loss?
Mustarde flap—large skin muscle cheek rotation flap
What is the most common skin cancer on the eyelid?
Basal cell cancer
What is a Hughes flap?
A tarsoconjunctival flap from the upper eyelid, used to reconstruct >50% lower lid defects, for posterior lining
only
What is the second most common eyelid cancer?
Squamous cell cancer
What is the third most common eyelid cancer?
Sebaceous cell carcinoma
What is the recovery rate for Bell palsy?
Approximately 84%
What is the arcus marginalis?
Periosteal thickening at the orbital rim, where the orbital septum attaches
What is the lymphatic drainage for the eyelid?
Medial—submaxillary lymph nodes, lateral—parotid lymph nodes
What is the function of the procerus?
The muscle is continuous with the frontalis and inserts into the nasal bone to create horizontal wrinkles of the glabella
What are the oil-secreting glands of the eyelid?
Meibomian and zeis
What produces the aqueous layer of the eyelid?
Lacrimal gland
What is the anterior lamellae?
The skin and orbicularis
What is the posterior lamellae?
Conjunctiva and Mueller’s muscle in the upper eyelid. Conjunctiva and capsulopalpebral fascia in the lower
eyelid
What branches of the external carotid artery supply the lid?
Facial, internal maxillary, and superficial temporal
What is the vascular supply to the eyelid, from the internal carotid system?
Dorsal nasal, supratrochlear, supraorbital, lacrimal, and terminal branch of the ophthalmic artery
What is SOOF?
Suborbicularis oculi fat pad
What is ROOF?
Retro-orbicularis oculi fat pad
What autologous structure is useful in reconstruction of the posterior lamellae?
Hard palate mucosal graft
What fascia is commonly used to perform frontalis sling?
Tensor fascia lata
How many bones make up the orbit?
Seven
What is the distance from the orbit rim to the apex?
40 to 45 mm
Where does the nasolacrimal duct drain?
Beneath the inferior turbinate.
What is the globe malposition associated with orbital blowout?
Enophthalmos
What sites are involved in a zygomaticomaxillary complex (ZMC) fracture?
(1) Zygomaticofrontal, (2) zygomaticomaxillary, (3) zygomatic arch, (4) inferior orbital floor, and (5) anterior wall
of the maxilla
What is an entropion?
Inward rotation of the eyelid margin
What is a cause of pseudoptosis?
Enophthalmos
If myasthenia gravis is suspected, what test should be ordered?
Tensilon test—edrophonium injection leading to short-term improvement of ptosis
When are symptoms of ptosis worse in myasthenia?
Later in the day
