BCSC Plastics Flashcards

1
Q

Are capillary hemangiomas in children benign or malignant?

A

Benign, but may cause mass effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

When do capillary hemangiomas usually present?

A

birth to first few weeks of life, enlarging over first 6-12 months

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What percent of capillary hemangiomas resolve within the first 4-5 years of life?

A

75%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Is CVS a risk factor for capillary hemangioma?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How can MRI be used to distinguish capillary hemangiomas from other vascular malformations?

A

MRI will show fine vascular channels and high blood flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What part of the orbit do capillary hemangiomas have a propensity for?

A

superonasal quadrant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the major complications of capillary hemangiomas?

A

Amblyopia, strabismus, and anisometropia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are possible treatments for capillary hemangiomas?

A

topical or systemic beta blockers, steroids, surgical excision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the most common benign neoplasm of the orbit in adults?

A

Cavernous hemangioma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the histology of the cavernous hemangioma?

A

The lesions are encapsulated and composed of large cavernous spaces containing RBCs. The walls contain smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Are arteriography and venography useful in evaluation of cavernous hemangiomas?

A

No, there is little communication with the systemic circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the management of cavernous hemangioma?

A

Surgical excision after imaging if there is compromise of ocular function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Are hemangioperictyomas common?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the histology of the hemangiopericytoma?

A

Plump pericytes surround a rich capillary network

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

When do lymphatic malformations (lymphangiomas) generally present?

A

Within the first decade of life in the orbit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the histology of the lymphatic malformation?

A

They generally contain both lymphatic and venous components and are characterized by large, serum-filled channels that are lined by flat endothelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Are lymphatic malformations technically neoplasms?

A

No, because their endothelial cells do not proliferate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the features of lymphatic malformations on MRI?

A

multiple grape-like cystic lesions with fluid-fluid layering of the serum and red blood cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How can a venous malformation be diagnosed?

A

With demonstration of engorgement on spiral CT during a Valsalva maneuver (decreasing venous return)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the management oforbital venous malformations?

A

Conservative, with surgical excision only if there is vision-threatening compressive optic neuropathy; embolization with coils may also be employed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are arteriovenous fistulas?

A

acquired lesions caused by abnormal direct communication between an artery and a vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the possible causes of an AV fistula?

A

Trauma or degeneration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the 2 forms of AV fistula?

A

Carotid cavernous fistula (typically occurs after a basal skull fracture) and Spontaneous Dural Cavernous Fistula (degenerative process in older pts with HTN and atherosclerosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Do carotid cavernous fistulas have high blood flow?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are findings associated with carotid cavernous fistula?

A

Tortuous epibulbar vessels, audible bruit, pulsatile proptosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How does a carotid cavernous fistula cause damage?

A

Bypass of the capillary network results in ocular ischemia; Direct passage of blood into the venous system results in venous outflow obstruction –> increased IOP, choroidal effusions, blood in Schlemm canal, nongranulomatous iritis, increased cavernous sinus pressure leading to CN III, IV, and VI palsies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How do Dural Cavernous Fistulas occur?

A

small meningeal arterial branches communicate with venous drainage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How does chronic red eye occur in Dural Cavernous Fistula?

A

Arterialization of the conjunctival vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How is embolization of AV fistulas usually accomplished?

A

endovascular transarterial route

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the types of neural tumors of the orbit?

A

optic nerve gliomas, neurofibromas, meningiomas, and schwannomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Are optic nerve gliomas benign or malignant?

A

They are benign in the first decade of life, but can be malignant if onset is in the adult male

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the prognosis for malignant optic nerve gliomas?

A

Very poor – usually death within 6-12 months even with treatment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What percent of optic nerve gliomas are associated with neurofibromatosis?

A

50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are the clinical findings of optic nerve glioma?

A

gradual, painless, unilateral axial proptosis associated with loss of vision and an afferent pupillary defect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the gross pathology of the optic nerve glioma?

A

Smooth, fusiform intradural lesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Where do optic nerve gliomas in patients with NF usually proliferate?

A

the subarachnoid space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are the findings of optic nerve glioma on CT or MRI?

A

fusiform enlargement of the optic nerve with sterotypical kinking of the nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What are the possible treatment options for optic nerve glioma?

A

Observation only, surgical excision, radiation therapy, radiation therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Of what are neurofibromas composed?

A

proliferating Schwann cells within nerve sheaths with occasional axons, endoneural fibroblasts, and mucin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are the two types of neurofibromas?

A

PlexiformNeurofibromas and Discrete Neurofibromas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Which type of neurofibroma (plexiform or discrete) is easier to excise surgically?

A

Discrete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

In which form of neurofibromatosis do plexiform neurofibromas usually occur?

A

NF 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is the inheritance of NF 1?

A

autosomal dominant with incomplete penetrance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What are the clinical findings in NF 1?

A

Plexiform neurofibromas of the lateral aspect of the upper eyelid (S-shaped contour of lid), pulsating proptosis, optic nerve glioma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What are meningiomas?

A

Invasive tumors arising from the arachnoid villi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What are the findings of meningioma on neuroimaging?

A

diffuse tubular enlgargement of the optic nerve with contrast enhancement. On CT, calcification may be seen within the meningioma referred to as tram-tracking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What is the most common primary orbital malignancy of childhood?

A

Rhabdomyosarcoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is the average age of onset of rhabdomyosarcoma?

A

8-10 yrs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What is the common clinical picture of rhabdomyosarcoma?

A

child with sudden onset, rapidly-progressive unilateral proptosis with discoloration of the eyelids; ptosis and strabismus may also be present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

From what do rhabdomyosarcomas arise?

A

Undifferentiated pluripotential mesenchymal elements of the orbital soft tissues (not from the extraocular muscles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What are the 4 categories of rhabdomyosarcoma?

A

Embryonal, Alveolar, Pleomorphic, Botryoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is the common management of rhabdomyosarcoma?

A

Biopsy via anterior orbitotomy, surgical excision if there is a pseudocapsule, chemo and radiation, possible exenteration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is the most common form of rhabdomyosarcoma?

A

Embryonal (80%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Which form of rhabdomyosarcoma has the worst prognosis?

A

Alveolar, 10-year survival rate 10%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Which form of rhabdomyosarcoma has the best prognosis?

A

Pleomorphic, 97% survival rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What portion of orbital tumors are lymphoproliferative neoplasms?

A

20%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is the most common type of orbital lymphoproliferative disease?

A

Malignant non-Hodgkin B-cell lymphoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What percent of orbital lymphomas are MALT lesions?

A

40%-50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What percent of patients with orbital MALT will develop systemic disease at 10 years?

A

50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What is the classic clinical presentation of a lymphoproliferative lesion?

A

Gradually progressive painless mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is the classic clinical appearance of a lymphoproliferative lesion?

A

Salmon patch underneath the conjunctiva or located anteriorly in the orbit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What type of biopsy is preferred for lymphoproliferative lesions?

A

Open biopsy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What percent of orbital lymphoproliferative lesions have on diagnosis or will have associated systemic disease within 5 years?

A

50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What is the treatment of choice for localized orbital lymphoproliferative lesions?

A

Radiation, with a dose of 2000 to 3000 cGy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What is the most common presentation of Langerhans cell hystiocytosis in the orbit?

A

A lytic lesion of the superotemporal orbit with associated orbital inflammation (which may be confused initially for infectious orbital cellulitis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What are the 4 types of adult xanthogranuloma of the orbit (in order of frequency)?

A

1) Necrobiotic xanthogranuloma (NBX), 2) Adult-onset asthma with periocular xanthogranuloma (AAPOX), 3) Erdheim-Chester disease (ECD), 4) Adult-onset xanthogranuloma (AOX)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What do most lacrimal gland masses represent?

A

Non-specific inflammation of the lacrimal gland (dacryoadenitis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What is a common dichotomy of lacrimal gland tumors?

A

Epithelial origin vs. non-epithelial origin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What is the most common epithelial tumor of the lacrimal gland?

A

The pleomorphic adenoma (benign mixed tumor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What is the common clinical presentation of a pleomorphic adenoma of the lacrimal gland?

A

Patient in the 4th or 5th decade of life presenting with slowly progressive, painless downward displacement of the globe with axial proptosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Should a suspected pleomorphic adenoma of the lacrimal gland be biopsied?

A

No, it should be completely excised surgically maintaining an intact pseudocapsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What is the most common malignant tumor of the lacrimal gland?

A

The adenoid cystic carcinoma (cylindroma)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What percent of patients with orbital neuroblastoma survive?

A

90% if diagnosed before age 1, 10% if diagnosed after age 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What is the most common type of leukemia to metastasize to the orbit?

A

Acute lymphoblastic leukemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What are the two most common metastases to the orbit?

A

Breast and lung tumors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What is the most common orbital metastasis in women?

A

Breast carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What is the most common orbital metastasis in men?

A

Bronchogenic carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

What part of the face do Le Fort fractures involve?

A

the maxilla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What is a Le Fort I fracture?

A

a low transverse maxillary fracture above the teeth with no orbital involvement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

What is a Le Fort II fracture?

A

a pyramidal fracture involving the nasal, lacrimal, and maxillary bones, as well as the medial orbital floor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What is a Le Fort III fracture?

A

craniofacial disjunction with involvement of the orbital floor and medial and lateral orbital walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

What is craniofacial disjunction?

A

A condition in which the entire facial skeleton is completely detached from the base of the skull and suspended only by soft tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What are the sites of fracture in a tripod fracture of the zygomaticomaxillary complex (ZMC)?

A

the lateral orbital rim, inferior orbital rim, zygomatic arch, lateral wall of the maxillary sinus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

Are orbital roof fractures more common in adults or children?

A

Children. Since the frontal bone has not pneumatized yet in children, frontal trauma is more likely to extend to the orbital roof in children, whereas in adults, the frontal sinus acts as a crumple zone and dissipates energy of frontal impacts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What is another name for a direct medial orbital fracture?

A

A naso-orbital-ethmoidal fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What are the common clinical characteristics of a nas-orbital-themoidal fracture?

A

Depressed bridge fo the nose and traumatic telecanthus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

What is an indirect medial orbital fracture?

A

A fracture of the medial orbit resulting from a blowout fracture of the orbital floor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

What are the common physicial sings of an orbital floor fracture?

A

Eyelid edema and ecchymosis; diplopia with limitation of upgaze, downgaze, or both; enophthalmos and ptosis of the globe; hypoesthesia in the distribution of the infraorbital nerve; orbital and eyelid emphysema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What is an exception to initial observation of an orbital floor fracture?

A

Inferior rectus trapping beneath a trapdoor fracture (IR in maxillary sinus on CT) in pediatric patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

In which situations is surgery advisable in the case of an orbital floor fracture?

A

1) Diplopia with limitation of upgaze and/or downgaze within 30 degrees of primary position with positive forced ductions 7-10 days after injury and with radiologic confirmation; 2) Enophthalmos that exceeds 2mm and is cosmetically unacceptable to the patient; 3) Large fractures involving at least half of the orbital floor, particularly when associated with large medial wall fractures (determined by CT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

Can MRI be safely performed with a BB in the orbit?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

Should BBs be removed from the orbit when found?

A

Usually, they are best left in place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

What are the 5 surgical spaces within the orbit?

A

1) subperiorbital (subperiosteal) space (a potential space); 2) extraconal space (outside the muscle cone, between the cone and the periorbita); 3) episcleral (sub-Tenon) space (between Tenon capsule and globe); 4) intraconal space (inside muscle cone); 5) subarachnoid space (between optic nerve and nerve sheath)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

Which type of orbitotomy incision provides the best cosmetic result when attempting to access the supraorbital rim?

A

An upper eyelid crease incision (rather than an incision directly over the superior orbital rim)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

What approach is now usually used to perform an orbital decompression?

A

Transconjunctival incision with lateral cnatholysis to disinsert and evert the lower eyelid for exposure of the inferior and lateral orbital rims. This incision can be extended superonasally with a transcaruncular approach to access the medial orbital wall for bone removal and decompression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

If used in orbital surgery, how long is a drain generally kept in place

A

no more than 24-36 hours

97
Q

Should visual acuity be checked frequently after orbital surgery?

A

Yes, especially in the first 12 hours after surgery

98
Q

Should patching of the operative site be performed after orbital surgery?

A

No, since this can delay diagnosis of postoperative hermorrhage

99
Q

In which situations is enucleation the anophthalmic surgery of choice?

A

If the nature of intraocular pathology is unknown or if ocular tumor is suspected

100
Q

What is a benefit of enucleation over evisceration?

A

Lower likelihood of sympathetic ophthalmia, particularly with severely traumatized eyes

101
Q

Which are the ocular tumors that most commonly require enucleation?

A

Retinoblastoma and choroidal melanoma

102
Q

What are common indications for enucleation?

A

1) intraocular malignancy not amenable to alternative modes of therapy such as external-beam radiation or episcleral plaque brachytherapy; 2) blind eyes with opaque media and no known cause of ocular disease; 3) blind painful eyes; 4) severely traumatized eyes without hope for visual recovery

103
Q

What surgical approaches can be used for obtaining exposure for enucleation?

A

lateral canthotomy or superomedial approach

104
Q

What are the components of an acceptable enucleation?

A

1) orbital implant of sufficient volume; 2) socket lined with conjunctiva or other mucous membrane; 3) eyelids with normal appearance and adequate tone; 4) good transmission of motility from implant to prosthesis; 5) comfortable ocular prosthesis that looks similar to the normal eye

105
Q

What is the value of a dermis-fat graft for an enucleation performed in a child?

A

The dermis-fat graft grows in children providing necessary pressure to promote orbital growth

106
Q

What are the advantages of evisceration?

A

1) less disruption of orbital anatomy; 2) good prosthesis motility (EOMs remain attached to sclera); 3) preferred treatment in some cases of endophthalmitis; 4) technically simpler than enucleation; 5) lower rates of migration, extrusion, and reoperation than enucleation

107
Q

What are the disadvantages of evisceration when compared to enucleation?

A

1) not indicated if ocular tumor suspected or in patients with severe pthisis; 2) theoretically increased risk of sympathetic ophthalmia; 3) provides less complete pathologic specimen than does enucleation

108
Q

What are the functions of an orbital implant?

A

1) replace lost orbital volume; 2) maintain structure of the orbit; 3) impart motility to the overlying ocular prosthesis

109
Q

What are the different classes of spherical orbital implants?

A

Inert (glass, silicone, MMA) and Biointegrated (hydroxyapatite, porous polyethylene)

110
Q

What are possible locations for orbital implants?

A

Within the Tenon capsule or behind the posterior Tenon capsule in the muscle cone

111
Q

When is an ocular prosthesis usually fitted after anophthalmic surgery?

A

4-8 weeks

112
Q

What are common complications of anophthalmic surgery?

A

1) deep superior sulcus due to decreased orbital volume; 2) contracture of fornices; 3) exposure and extrusion of the implant; 4) contracted socket; 5) anophthalmic ectropion; 6) anophthalmic ptosis; 7) lash margin entropion

113
Q

What are circumstances in which exenteration may be appropriate?

A

1) destructive tumors extending into the orbit; 2) intraocular melanomas or retinoblastomas extending outside the globe but without distant metastases; 3) malignant epithelial tumors of the lacrimal gland; 4) sarcomas not responding to nonsurgical therapy; 5) fungal infection (orbital zygomycosis)

114
Q

What are the types of orbital exenteration?

A

Subtotal, Total, and Extended

115
Q

What are the 5 structural planes of the face?

A

1) Skin; 2) Subcutaneous tissue; 3) Superficial musculoaponeurotic system (SMAS) and mimetic muscles; 4) deep facial fascia; 5) plane containing the facial nerve, parotid duct, and buccal fat pad

116
Q

How are the mimetic muscles divided?

A

Upper face and lower face (superficial and deep)

117
Q

Which muscles animate the forehead and glabella?

A

frontalis, corrugator, and procerus

118
Q

Which muscle depresses the eyebrows and closes the eyelids?

A

orbicularis oculi

119
Q

Which muscle elevates the eyebrows?

A

frontalis

120
Q

Which muscles are the superficial mimetic muscles?

A

platysma, zygomaticus major, zygomaticus minor, risorius

121
Q

Which muscles are the deep mimetic muscles?

A

buccinator, mentalis, levator anguli oris

122
Q

What are the 5 major branches of the facial nerve (CN VII)?

A

Temporal, zygomatic, buccal, marginal mandibular, cervical

123
Q

What are the 7 structural layers of the eyelids?

A

1) skin and subcutaneous tissue; 2) muscles of protraction; 3) orbital septum; 4) orbital fat; 5) muscles of retraction; 6) tarsus; 7) conjunctiva

124
Q

What defines the upper eyelid crease?

A

The attachments of the levator aponeurosis to the pretarsal orbicularis bundles and skin

125
Q

What defines the upper eyelid fold?

A

the loose preseptal skin and sucutaneous tissues above the confluence of the levator aponeurosis and orbital septum

126
Q

What are the divisions of the orbicularis oculi muscle?

A

Orbital, pre-septal, and pre-tarsal

127
Q

Which divisions of the orbicularis oculi muscle are involved in involuntary movement of the eyelids?

A

Pre-septal and pre-tarsal

128
Q

Where does the orbital septum fuse with the levator aponeurosis in the upper eyelid?

A

2-5 mm above the superior tarsal border in non-Asians

129
Q

Where does the orbital septum fuse with the capsulopalpebral fascia in the lower eyelid?

A

At or below the inferior tarsal border

130
Q

What conditions can lead to anterior herniation of the orbital fat in the aging eyelid?

A

Thinning of the orbital septum and laxity of the orbicularis

131
Q

How many orbital fat pockets are there in the upper and lower lids, respectively?

A

2 in the upper lid and 3 in the lower lid.

132
Q

Where does the orbital fat lie in the upper and lower lids?

A

posterior to the orbital septum and anterior to the levator aponeurosis (upper lid) or the capsulopalpebral fascia (lower lid)

133
Q

What are the retractors of the upper lid?

A

Levator muscle (with levator aponeurosis) and superior tarsal muscle (Muller muscle)

134
Q

What are the retractors of the lower lid?

A

Capsulopalpebral fascia and inferior tarsal muscle

135
Q

Where is the peripheral arterial arcade found?

A

between the levator aponeurosis and the Muller muscle, just above the superior tarsal border

136
Q

How tall are the superior and inferior tarsal plates?

A

10-12mm (superior) and 4mm (inferior)

137
Q

How are the tarsal plates connected to the periosteum of the orbit?

A

Via the medial and lateral canthal tendons

138
Q

Where is the mucocutaneous junction of the eyelid located?

A

Just posterior to the meibomian gland orifices on the eyelid margin

139
Q

When do most congenital anomalies of the eyelids occur?

A

During the second month of gestation

140
Q

What are the components of Blepharophimosis Syndrome?

A

Blepharophimosis, telecanthus, epicanthus inversus, severe ptosis.

141
Q

What are the common associations of congenital ectropion?

A

Blepharophimosis syndrome, Down syndrome, and icthyosis

142
Q

What is euryblepharon?

A

From the Greek eurus, meaning “wide” – unilateral or bilateral horizontal widening of the palpebral fissure, sometimes associated with blepharophimosis syndrome

143
Q

What is ankyloblepharon?

A

From the Greek prefix ankyl, meaning “stiff, unmovable, adhesion” – partial or complete fusion of the eyelids by webs of skin

144
Q

What is epicanthus?

A

a medial canthal fold that may result from immature midfacial bones or a fold of skin and subcutaneous tissue

145
Q

What are the 4 types of epicanthus?

A

tarsalis (upper eyelid), inversus (lower eyelid), palpebralis (equal between upper and lower eyelids), supraciliaris (arising from the eybrow region running to the lacrimal sac

146
Q

What is epiblepharon?

A

A condition in which the lower eyelid pretarsal muscle and skin ride above the lower eyelid margin to forma horizontal fold of tissue, causing the lashes to assume a vertical position.

147
Q

What is congenital distichiasis?

A

A rare, sometimes hereditary condition in which an extra row of lashes is present in place of meibomian gland orifices

148
Q

Which skin is usually used for grafting eyelid defects?

A

Contralateral eyelid or pre-auricular or post-auricular skin

149
Q

Should hair-bearing skin grafts be used around the eye?

A

No, they should be avoided if possible

150
Q

Which is preferred in eyelid reconstruction – full-thickness or split-thickness grafts?

A

Full-thickness grafts. Split-thickness grafts should be used only when adequate full-thickness skin is not available

151
Q

Under what condition can direct closure of an upper eyelid defect be performed?

A

<= 33% of the eyelid margin is involved.

152
Q

What procedure can be performed in a patient in whom extensive sacrifice of the canaliculi has occrred in the resection of a tumor?

A

A conjunctivodacryocystorhinostomy with a Jones tube can be performed, but only after an observed recurrence-free period often lasting up to 5 years.

153
Q

How many days prior to elective periocular surgery is warfarin generally stopped?

A

2-5 days, if approved by PCP

154
Q

How many days prior to elective periocular surgery is aspirin generally stopped?

A

5 days, if approved by PCP

155
Q

How many days prior to elective periocular surgery are NSAIDs generally stopped?

A

3 days, if approved by PCP

156
Q

What are the five classes of ectropion?

A

1) congenital; 2) involutional; 3) paralytic; 4) cicatricial; 5) mechanical

157
Q

What is the most common cause of ectropion?

A

Involutional ectropion (which is itself most often due to horizontal eyelid laxity either in the medial or lateral canthal tendons)

158
Q

Does involutional ectropion usually affect the upper or lower lid?

A

Lower lid

159
Q

What are the 3 most commonly used surgical procedures in treating involutional ectropion?

A

Medial spindle procedure, Tarsal strip proceudre, and Reinsertion of the lower eyelid retractors

160
Q

What are the steps in surgically treating cicatricial ectropion of the lower eyelid?

A

1) surgical release of vertical cicatricial traction; 2) horizontal tightening with a lateral tarsal strip operation; 3) vertical lengthening of the anterior lamella via a midface lift or full-thickness skin graft

161
Q

What are the 4 types of entropion?

A

1) congenital; 2) acute spastic; 3) involutional; 4) cicatricial

162
Q

What is the most common situtation in which acute spastic entropion develops?

A

Postoperative development due to ocular irritation and inflammation sustained during intraocular surgery in a patient with unrecognized or mild involutional eyelid changes

163
Q

How is horizontal laxity of the eyelid detected?

A

1) Poor eyelid tone (snapback test) or 2) ability to pull the eyelid more than 6mm from the globe (distraction test)

164
Q

What are the clinical signs that may indicate disinsertion of the eyelid retractors?

A

1) a white subconj line several millimeters below the inferior tarsal border caused by the leading edge of the detached retractors; 2) deeper than normal inferior fornix; 3) lower eyelid margin sitting higher than normal; 4) little or no inferior movement of the lower eyelid on downgaze (limited lower lid excursion)

165
Q

What are the three types of procedures for repair of involutional entropion?

A

1) Temporizing measures, 2) Horizontal tightening procedures, 3) repair of the retractors

166
Q

What are common temporizing measures for repair of involutional entropion?

A

Quickert sutures and thermal cautery

167
Q

What are the three etiologic factors in involutional entropion?

A

1) disinsertion of the eyelid retractors, 2) overriding orbicularis, 3) horizontal laxity

168
Q

How quickly can trichiasis recur after mechanical epilation?

A

3-8 weeks

169
Q

What are the therapies available for trichiasis?

A

Mechanical epilation, electrolysis, radiofrequency ablation, cryotherapy, argon laser, full-thickness pentagonal resection with primary closure

170
Q

What are the five etiologic variants of ptosis (blepharotosis)?

A

1) myogenic, 2) aponeurotic, 3) neurogenic, 4) mechanical, 5) traumatic

171
Q

What is the most common etiology of congenital ptosis?

A

poorly developed levator muscle (myogenic cause)

172
Q

What is the most common etiology of acquired ptosis?

A

stretching or disinsertion of the levator aponeurosis (aponeurotic cause)

173
Q

What are the 5 clinical measurements used to evaluate ptosis?

A

1) margin-reflex distance, 2) vertical interpalpebral fissure height, 3) upper eyelid crease position (distance from UL crease to UL margin), 4) levator function (upper eyelid excursion), 5) presence of lagophthalmos

174
Q

What is MRD1?

A

the distance from the upper eyelid margin to the corneal light reflex in primary position (may be zero or negative)

175
Q

What is MRD2?

A

the distance from the corneal light reflex to the lower eyelid margin

176
Q

What does the sum of MRD1 and MRD2 represent?

A

The vertical interpalpebral fissure height

177
Q

How is levator function measured?

A

By fixating the brow to eliminate frontalis contributions and measuring the distance moved by the upper eyelid margin from downgaze to upgaze (ULE or upper lide excursion)

178
Q

What are conditions in which synkinesis of the lid and EOM or jaw occurs?

A

Marcus Gunn jaw-wink, aberrant regeneration of CN III or CN VII, certain forms of Duane sydnrome

179
Q

Does ptosis tend to improve or worsen in downgaze when congenital?

A

Congenital ptosis improves in downgaze, unlike acquired ptosis, which worsens.

180
Q

Is the crease in the typical Asian eyelid higher or lower than in the typical Caucasian eyelid?

A

lower

181
Q

What percent of patients with congenital ptosis develop amblyopia?

A

20%

182
Q

What congenital conditions involve both EOM dysfunction and ptosis?

A

1) combined superior rectus/levator muscle maldevelopment; 2) congenital oculomotor palsy

183
Q

What acquired conditions involve both EOM dysfunction and ptosis?

A

1) ocular or systemic myasthenia gravis; 2) Chronic progressive external ophthalmoplegia (CPEO); 3) oculopharyngeal dystrophy; 4) oculomotor palsy with or without aberrant regeneration

184
Q

What conditions involve both ptosis and pupillary abnormalities?

A

1) Horner syndrome, 2) CN III palsy

185
Q

How is functional visual impairment assessed in patients with ptosis?

A

Visual field testing with the eyelids untaped (natural state) and taped (approximating post-surgical state)

186
Q

What is the most common etiology of congenital myogenic ptosis?

A

dysgenesis of the levator muscle

187
Q

What are common causes of acquired or late-onset myogenic ptosis?

A

muscular dystrophy, chronic progressive external ophthalmoplegia, oculopharyngeal dystrophy

188
Q

What is the most common form of ptosis?

A

Acquired aponeurotic ptosis

189
Q

What is the mechanism of aponeurotic ptosis?

A

stretching or dehiscence of the levator aponeurosis or disinsertion from its normal position

190
Q

Is the upper eyelid crease usually higher or lower than normal in acquired aponeurotic ptosis?

A

higher

191
Q

What are the causes of congenital neurogenic ptosis?

A

Congenital CN III palsy, congenital Horner syndrome, Marcus-Gunn jaw-winking syndrome

192
Q

What is the cause of ptosis in Horner syndrome?

A

an innervational deficit to the sympathetically innervated Muller muscle (an eyelid elevator second in importance to the levator)

193
Q

What is the analog of the Muller muscle in the lower lid?

A

The inferior tarsal muscle

194
Q

What effect does Horner syndrome have on the inferior tarsal muscle?

A

since the inferior tarsal muscle, like the Muller muscle, has sympathetic innervation, decreased retraction of the lower lid occurs, resulting in a higher than normal lower lid (sometimes called a lower eyelid reverse ptosis)

195
Q

What are the two common causes of acquired oculomotor nerve palsies?

A

1) Ischemic (can be self-limited, especially if pupil-sparing) and 2) Compressive

196
Q

What percent of myasthenia gravis patients have thymomas?

A

10%, thus warranting consideration of chest CT scanning at time of diagnosis

197
Q

What are the tests available for myasthenia gravis?

A

1) edrophonium test; 2) ice-pack test (which exploits inhibition of acetylcholinesterase at low temperatures); 3) sleep/rest test; 4) acetylcholine receptor antiody test

198
Q

What are the common medical treatments for myasthenia gravis?

A

acetylcholinesterase inhibitors and steroids

199
Q

What surgical intervention is sometimes performed for myasthenia gravis after medical treatments are attempted?

A

frontalis suspension

200
Q

What is dermatochalasis?

A

a condition in which excess upper eyelid skin overhangs the eyelid margin, transects the pupil, and gives the appearance of a true ptosis of the eyelid margin

201
Q

What are the 3 categories of surgical procedures commonly used in ptosis repair?

A

1) External (transcutaneous) levator advancement; 2) internal (transconjunctival) levator/tarsus/Muller muscle resection approaches; 3) frontalis muscle suspensions

202
Q

What are the most common causes of eyelid retraction?

A

1) Thyroid eye disease, 2) recession of the vertical rectus muscles, 3) overly aggressive skin excision in blepharoplasty, 4) overcompensation for a contralateral ptosis

203
Q

What histological changes are seen in the eyelid retractors in TED?

A

inflammatory infiltration and fibrotic contraction of the sympathetically innervated retractors (Muller muscle and inferior tarsal muscle)

204
Q

What is the most common cause of paralytic ectropion?

A

CN VII paralysis or palsy

205
Q

What is the most commonly performed procedure for treatment of paralytic lagophthalmos?

A

gold weight loading of the upper eyelid

206
Q

Is neuroimaging indicated in the workup of blepharospasm?

A

usually not

207
Q

What are the clinical features of Benign Essential Blepharospasm?

A

increased blinking, involuntary spasm of the eyelid protractor muscles; may progress to intermittent episodes of inability to open the eyelids

208
Q

What is the treatment of choice for Benign Essential Blepharospasm (BEB)?

A

repeated periodic injection of botulinum toxin A

209
Q

What are the kinetics of botulinum toxin A injections?

A

Onset: 2-3 days, Peak effect: 7-10 days, Duration of action: 3-4 months

210
Q

Is the onset of action of botulinum toxin B faster or slower than that of botulinum toxin A?

A

faster

211
Q

What are the complications associated with botulinum toxin injection for BEB?

A

bruising, belpharoptosis, ectropion, epiphora, diplopia, lagophthalmos

212
Q

What are the clinical features of hemifacial spasm?

A

intermittent synchronous gross contractures of an entire side of the face

213
Q

What is the most common cause of hemifacial spasm?

A

vascular compression of the facial nerve at the brain stem

214
Q

What is blepharochalasis?

A

A rare familial variant of angioneurotic edema, commonly occurring in young females, that is characterized by episodes of inflammatory edema of the eyelids

215
Q

What are three complications of blepharoplasty?

A

Loss of vision (may be due to orbital hemorrhage), diplopia (due to injury of inferior oblique, inferior rectus, or superior oblique), and excessive removal of eyelid skin

216
Q

What are procedures for treating brow ptosis?

A

Browpexy, direct brow lift, and endoscopic or pretrichial brow lift

217
Q

What 2 of the most important characteristics in evaluating a child with congenital tearing?

A

1) Frequency of tearing (constant vs. intermittent) and 2) Presence or absence of mucopurulent discharge

218
Q

What does constant tearing with minimal mucopurulence in a child with congenital tearing suggest?

A

upper nasolacrimal system block caused by punctal or canalicular dysgenesis

219
Q

What does constant tearing with frequent mucopurulence in a child with congenital tearing suggest?

A

complete obstruction of the NLD

220
Q

What does intermittent tearing with mucopurulence in a child with congenital tearing suggest?

A

Intermittent obstruction of the NLD, consistent with impaction of a swollen inferior nasal turbinate, as might be expected with a URI

221
Q

What is the most important maneuver in examining a child with congenital tearing?

A

digital pressure over the lacrimal sac

222
Q

What does complete absence of the punctum and canalicular system necessitate?

A

conjunctivodacryocystorhinostomy (CDCR)

223
Q

What percent of all congenital NLD obstructions resolve in the first year of life?

A

90%

224
Q

What are conservative measures for NLD obstruction?

A

observation, lacrimal massage, topical antibiotics

225
Q

What is referred to as the “hard stop” in NLDP?

A

encountering the nasal aspect of the lacrimal sac and the adjacent lacrimal bone

226
Q

In what percent of patients under 13 months of age is NLDP successful at relieving obstruction?

A

90%

227
Q

Is NLDP performed in adults?

A

No, probing is generally limited to the canalicular system, and does not extend to the NLD as it is potentially traumatic and rarely successful in adults at relieving obstruction

228
Q

Into what two categories can patients with true epiphora be grouped?

A

1) hypersecretion of tears, 2) impairment of drainage

229
Q

What are the tests involved in evaluation of the lacrimal drainage system?

A

1) Dye disappearance test, 2) Jones I test, 3) Jones II test, 4) Lacrimal drainage system irrigation, 5) NLDP 6) Nasal endoscopy, 7) contrast dacryocystography or dacryoscintigraphy

230
Q

What are the potential etiologies of canalicular obstruction?

A

1) lacrimal plugs, 2) chemotherapeutic meds (5-FU, docetaxel, idoxuridine), 3) Infection, 4) inflammation, 5) trauma, 6) neoplasm

231
Q

What does conjunctivodacryocystorhinostomy (CDCR) involve?

A

A bypass of the lacrimal drainage system with a glass tube (Jones tube) placed through a new opening in the caruncle, through an osteotomy, and into the middle nasal meatus

232
Q

What are the potential etiologies of acquired NLD obstruction?

A

1) Involutional stenosis, 2) dacryolith, 3) Sinus disesase, 4) trauma, 5) inflammatory disease (sarcoid), 6) lacrimal plugs, 7) radioactive iodine for thyroid malignancy, 8) Neoplasm

233
Q

What does a dacryocystorhinostomy (DCR) involve?

A

The creation of an anastomosis between the lacrimal sac and the nasal cavity (to bypass the NLD) through a bony ostium, either by intranasal or transcutaneous approach.

234
Q

Why do most surgeons recommend repair of all canalicular lacerations?

A

50% of patients with one functional canaliculus will still experience epiphora and primary repairs have a much higher likelihood of success than secondary reconstructions

235
Q

How soon after injury should a canalicular repair be performed?

A

As soon as possible, preferably within 48 hours

236
Q

What is the most common pathogen involved in canaliculitis?

A

Actinomyces israelii

237
Q

Should irrigation or probing of the canalicular system be performed in acute dacryocystitis?

A

No, irrigation and probing should be avoided until the infection subsides

238
Q

Are topical antibiotics effective in treating acute dacryocystitis?

A

No, not usually. Oral or parenteral antibiotics are usually required.