Plastic And Reconstructive Surgery Flashcards
1
Q
In using GAN for facial nerve reinnervation, what length of the GAN can be harvested?
Sural nerve?
Medial antebrachial cutaneous nerve?
A
10cm
70cm
20cm
2
Q
How many epineural sutures in nerve-nerve anastomosis?
A
4, with 8-10mm of extra length for each anastamosis
3
Q
Most common smile form dominated by action of zygomaticus major muscle. Corners of mouth move laterally and superiorly
A
Mona lisa smile
4
Q
Smile type dominated by levator labii superioris muscle. Vertical elevation of the upper lip, lateral elevation of the upper mouth.
A
Canine smile.
5
Q
Smile type with simultaneous elevation of the elevators and depressors of the lips and angles of the mouth.
A
Full denture smile/toothy smile
6
Q
When to perform EMG prior to performing reanimation?
A
12 mos after
7
Q
Most desired neural source for rejuvination of the paralyzed face?
A
Ipsilateral facial nerve
8
Q
Single most important test to determine type of operative procedure to be performed?
A
EMG
9
Q
Type of EMG pattern in reinnervation?
A
Polyphasic potentials
10
Q
EMG pattern where normal denervated muscles exist?
A
Denervation or fibrillation potentials
11
Q
EMG pattern when there is atrophy or congenital absence of muscle, provided there is proper electrode positioning.
A
Electrical silence.
12
Q
Order of priority of reinnervation of nerve.
A
Buccal and zygomatic
Marginal mandibular
Temporal
Cervical
13
Q
Pinna is composed of what type of cartilage?
A
Fibrocartilage
14
Q
Bowl of the ear has 3 concavities?
A
Cavum concha
Cymba concha
Fossa triangularis
15
Q
Sensory innervation if the ear?
A
CN 5 (auriculotemporal nerve)
CN 7
CN X (arnolds nerve)
C2 and c3
16
Q
Cartilagenous protuberance at the helix?
A
Darwins tubercle
17
Q
Otic placode arises at what week aog?
A
3rd
18
Q
Six hillocks arise at how many weeks aog?
A
6weeks aog
19
Q
Hillocks fuse at how many weeks?
A
12th week. Failure to do so will result in pre auricular sinuses.
20
Q
Cartilage formation begins at how many weeks aog? (Ear)
A
7 weeks
21
Q
Helix furls at how many weeks aog? Antihelix?
A
8-12 weeks, 12-16weeks
22
Q
Normal auriculocephalic angle?
A
25-35 degrees
23
Q
What auriculocephalic angle is considered abnormal?
A
> 40-45 degrees
24
Q
Pinna is positioned how many mm from the scalp?
A
15-20mm
25
Otoplasty done at what age?
5-6
26
What age does ear attain 85% of adult size?
Fully adult size?
3 years old
5-6 years old
27
Another name for V-Y pushback palatoplasty?
Oxford method
28
What is Sutherland's classification for nerve injury?
1st degree: reversible nerve block
2nd degree: Wallerian degeneration occurs but endoneurium stays intact and recovery is usually complete.
3rd degree: Endoneurium is destroyed but perineurium stays intact and recovery is incomplete.
4th degree: All is destroyed except for the epineurium; recovery is poor.
5th degree: Complete nerve transection; untreated recovery is not expected.
29
What is Hering's Law?
Unilateral ptosis with contralateral lid retraction-if you cover the ptotic eye with a patch for 30-60 minutes, the retracted eye will settle into the normal position and the ptotic eye will reveal itself.
30
What are the 4 strategies in the correction of a deviated septum?
1. Septum straightening
2. Complete osteotomies, including intermediate osteotomies
3. Long and wide spreader grafts for cartilaginous dorsal deviation
4. Strategic camouflage
31
Average epidermal thickness.
0.1 mm
32
Melanocytes are derived from?
Neural crest cells.
33
Epidermis is derived from?
Ectoderm
34
Dermis is derived from?
Endoderm.
35
Contains ground substance with highly developed microcirculation?
Papillary dermis
36
Contains thick bundles of collagen and elastic fibers?
Reticular dermis
37
Classification of flaps? (4) (FARM)
Free microvascular flaps
Arterial cutaneous (axial) flaps
Random cutaneous
Myocutaneous and fasciocutaneous flaps
38
Vascular supply of random cutaneous flaps?
Subdermal plexus. Plane of dissection subcutaneous fat. Survival of flaps depend on perfusion pressure and not length to width ratio.
39
Blood supply of acial flaps?
Septocutaneous aa.
40
Needs microvascular anastamosis of artery and vein.
Free microvascular flaps.
41
Flap can tolerate ___of complete avascularity and survive.
13 hours
42
Pressure at which there is no longer enough intravascular pressur to maintain capillary blood flow.
Critical closing pressure.
43
Neovascularization, which begins 3-4days after flap transposition, occurs at what rate?
0.2mm/day
44
New capillaries join preexisting flap vessels.
Inosculation.
45
Is a vasodilator and inhibitor of platelet aggregation.
PGI 2.
46
Tissues tolerate short periods of ischemia fairly well but exhibit histologic injury after return of perfusion. May be due to free radicals or lactic acid.
Reperfusion injury.
47
Principal structural framework of extracellular matrix?
Collagen 1 and 2.
48
Increase in strain seen when a constant stress is applied to th skin.
Creep
49
Decrease in stress when skin is held under tension in constant strain.
Stress relaxation.
50
Force required to counteract the attachment between the dermis and the underlying tissue.
Shearing force
51
Reduction of shearing force and wound tension is decreased with undermining of up to?
4cm
52
Most common intrinsic factor affecting flap survival is?
Inadequate blood flow
53
Improves blood flow, conditions tissue to ischemia, closes AV shunts.
Delay
54
How many hours delay to be effective?
At least 24 hours.
55
Vasodilators to increase flap viability?
```
Phenoxybenzamine
Phentolamine
Lidocaine
Isoflurane
Verapamil
Nitroglycerin (venous>arterial)
```
56
Leaching/hyperbaric oxygen improves what zone of viability?
Zone 1.
57
How long is the inflammatory phase?
2-5 days.
58
After ____ days, lymphocytes (-> Langerhans cells) become the dominating leukocyte subset.
14days
59
Nitric oxide greatest during?
Inflammatory phase.
60
How long is inflammatory phase in wound healing?
2-5 days
61
In day one, what are the predominant cells in the wound?
50% neutrophils -> chemokines
62
When do macrophages in the wound peak?
Day 3. Monocytes -> macrophages - central role im inflammatory phase.
63
How long is proliferation phase?
5 days to 3 weeks.
64
Proliferation phase recruits which cells?
Keratinocytes
Fibroblasts
Epithelial cells
65
3 aspects of proliferation phase?
1. Re epithelialization
2. Formation of granulation tissue
3. Wound contraction
66
How many days post op keratinocyte proliferation?
1-2 days
67
When does granulation tissue form?
3-4 days after injury, this replaces fibrin clot. Dermal matrix mostly fibroblasts. Angiogenesis starts.
68
Wound contraction happens when?
2nd week. Fibronectin plays a role in wound contraction by binding to fibrin and providing a scaffold for fibroblast and keratinocyte migration and tissue support.
69
When does remodeling phase in wound healing occur?
3rd week.
70
Wound strength at one week? 3 weeks? 3 months/12weeks?
3%, 20%, 80%
71
How many organisms/gram of tissue is infected?
10 power of 5 microorganisms/gram
72
Name 5 fasciocutaneous flaps. RULLS
```
Radial forearm
Ulnar forearm
Lateral arm
Lateral thigh
Suprascapular-parascapular
```
73
Radial forearm flap avn?
Radial artery
Vena comitantes
Medial and lateral antebrachial cutaneous
74
Ulnar forearm flap avn?
Ulnar aa
Vena comitantes
Medial and lateral antebrachial cutaneous
75
Lateral arm flap avn?
Posterior radial collateral
Posterior radial collateral
Posterior cutaneous nerve of the forearm
76
Lateral thigh flap avn?
Deep femoral
Vena comitantes
Lateral femoral cutaneous
77
Suprascapular-parascapular flap avn?
Subscapular
Subscapular
None
78
Name 2 muscle or myocutaneous flaps.
Rectus abdominis and latissimus.
79
Rectus abdominis flap avn?
Deep inferior epigastric
Same
Thoracodorsal
80
Latissimus flap avn?
Subscapular
Same
Thoracodorsal
81
Name 4 osteocutaneous flaps
Fibula (25 cm)
Iliac crest (14-16cm)
Radius
Scapula (10-14 cm)
82
Fibula osteocutaneous flap avn?
Peroneal
Peroneal
Lateral sural cutaneous
83
Radius osteocutaneous flap avn?
Radial
Vena comitantes
Medial or lateral antebrachial cutaneous
84
Scapular osteocutaneous flap avn?
Subscapular
Same
None
85
Iliac crest osteocutaneous flap avn?
Deep circumflex iliac
Same
None
86
Most versatile and reliable soft tissue flap?
Radial forearm fasciocutaneous. 12% of people have poor communication between deep and superficial arches.
87
Mainstay of mandibular recon. Most donatable bone in the body with up to 25cm of bone available for harvest.
Fibula
88
To avoid pathologic fracture, get only this % of radius?
40%
89
Highest quality of bone for osteointegration for dental implantation?
Iliac crest flap
90
Microsurgical technique: donor recipient vessel mismatch is?
3:1
91
When the anterior vessel wall is not lifted from the posterior vessel wall.
Back walling.
92
Two smooth forceps under sliding compression can confirm flow across the anastamosis.
Strip testing
93
Three common mechanisms of thrombosis?
Stasis
Hypercoagulability
Vessel injury
94
Most rapid method of anticoagulation?
Chewing
95
Most reliable monitoring technique and should be the end all test that determines the status of the flap.
Post op pin prick and visual inspection.
96
Most free flap anastamotic ischemic complications occur within?
48-72hrs
97
Need to re exploration and revision occurs (for flaps)?
8-9%
98
In venous anastamosis thrombosis. In arterial anastamosis thrombosis?
Only venous anastomosis should be explored; both arteeial and venous component explored.
99
3 variables that can be controlled in surgical lasers?
Power
Spot size
Exposure time
100
Co2 causes protein denaturation at what temperature?
60-65c; at 100c causes carbonization, disintegration, smoke and gas generation.
101
Among iv induction agents, can cause drop in bp?
Propofol
| Thiopental
102
Can be given im, but causes tachycardia and hypertension (iv induction)?
Ketamine
103
Mc benzodiazepene? Onset 2-4 mins.
Midazolam.
104
Depolarizing agent which raises K by 0.5 meq/l. Onset 60 seconds and duration 5mins.
Succinylcholine.
105
Cause of "purse string" appearance of the mouth in the elderly?
Resorption of the mandibular and maxillary bone
106
What is the Lyon's hypothesis for genetic disease?
Inactivation of one X chromosome in females.
107
Ideal nasofrontal angle
115-135 deg
108
Ideal nasolabial angle?
F: 95-110 degree
M: 90 - 95 degree
109
Ideal nasofacial angle?
30 - 40 degree (36)
110
Ideal nasomental angle?
120 - 132 degree (4mm, 2mm)
111
Ideal mentocervical angle?
80 - 95 degree
112
Ideal position of the medial eyebrow?
10mm above medial canthus
113
Normal intercanthal distance?
M: 26.5-38.7mm
F: 25.5-37.5mm
114
Normal palpebral opening?
10-12mm height
| 28-30mm width
115
Upper lid crease measurement?
7-15mm (11mm)
116
Tip projection measurement?
0.55-0.60
117
Lines of Blashko refers to:
Epidermal nevus
118
Milia measurement?
<3 mm
119
R/f for BCC?
Intermittent and intense sun exposure
120
R/f for SCC?
Cumulative sun exposure
121
Increased risk for melanoma?
Size >6mm
122
Picket fence histology?
Bcc
123
Aggressive form of bcc?
Ulcus terebrans
124
Aggressive bcc?
>6 mm face
| > 10mm forehead, scalp, and neck
125
Nevoid BCC otherwise known as?
Gorlin's tumor
126
Treatment for BCC?
Vismodegib - Sonic Hedgehog pathway
127
Causative for scc?
Hpv 16, 18 (31, 33, 38)
128
Aggressive scc?
>2 cm in diameter
| >4 mm depth
129
Worst prognostic indicator for scc?
Perineural invasion
130
Usually begin at 4th decade of life. Do not occur in palms and soles. Sharply demarcated and slightly raised, with keratotic plugs, flesh color to deep black. No malignant potential.
Seborrheic keratosis
131
Hundreds of this, associated with adenoca.
Lesser-trelat sign
132
Usually in adolescents. Looks like seborrheic keratosis but smaller.
Dermatosis papulosa nigra
133
Common wart is caused by what strain of hpv?
Hpv 2 and 3.
134
Dome like non pigmented papillomas, usually resolve spontaneously. Histologically with molluscum bodies.
Molluscum contagiosum.
135
Aka solar keratosis, precancerous lesion in which 5-20% develop scca after the 2nd decade of life. No sharp demarcation, spread peripherally.
Actinic keratosis.
136
Treatment for actinic keratosis?
Best removed and not watched. Usually by cryosurgery. If diffuse, can do dermabrasion, chemical peel, or laser resurface
137
Most common malignancy in humans
Bcca
138
_____of bcca occur in the head and neck?
86%, mostly on the nose
139
Genetic syndromes associated with bcca?
AD nevoid bcca
| Xeroderma pigmentosum
140
Is keratoacanthoma a variant of scca?
Yes. It proliferates, plateaus, then involutes
141
2 forms of keratoacanthoma?
Giant (reaching 5cm) and eruptive (hundreds of papules)
142
Can be used to induce involution in keratoacanthoma?
Methotrexate
143
3rd mc skin ca
Melanoma
144
2 growth phases of melanoma?
Radial
| Vertical
145
Mode of transmission for protruding ears?
AD, 5%. Insufficient helical furl and misshapen conchal bowl.
146
Mustarde's suture for protruding ears?
Multiple horizontal mattress
147
How does hyperbaric oxygen help flaps?
Increase by 20% o2 carrying capacity
148
Weight loss of ____ will decrease wound healing.
10%
