30 - 203 - EXCISIONAL SURGERY AND REPAIR, FLAPS AND GRAFTS Flashcards
What characteristics does each major cosmetic units share?
color, thickness, texture, sebaceous quality and hair density
What are the major cosmetic units of the face?
forehead, periorbital area, nose, lips and perioral area, chin, and cheeks
What is the optimal lengthto-width ratio of a simple ellipse?
3.5:1
- to minimize the formation of redundant tissue at the apices, otherwise known as “dog-ears” or “standing tri-cones.”
- The ratio may be increased to 4:1 or greater in locations with less tissue distensibility and in convex surfaces
What is the lengthto-width ratio of ellipse in locations with less tissue distensibility and in convex surfaces?
4:1 or greater
What is the lengthto-width ratio of ellipse in concave surfaces or in areas where the tissue is more lax and a lower tendency to produce cones?
3:1 or less
The apical angle between the 2 arciform incisions ranges from ? depending on the length-to-width ratio
37° to 74°
with the angles used in excisional surgery, the arcs are roughly how many percent longer than the straight line drawn down the middle of the ellipse
20%
A wound gains only how many percent of its final strength after 2 weeks?
7%
In settings where wound healing may be impaired due to the patient’s advanced age or underlying disease, what is the preferred type of closure?
interrupted sutures may be preferred, as interrupted sutures may have, with all other factors being equal, greater tensile strength and less potential to pull through thin skin or impair microcirculation
ROS of face and ears
5 - 7 days
ROS of neck
7 days
ROS of scalp
7 - 10 days
ROS of trunk and extremities
10 - 14 days
what do you call the freed cone after a dog ear repair?
burow’s triangle
- straight lines radiating in opposite directions connect the tips
- This leads to the formation of 2 triangles that enclose the defect and form a rhombic shape
- advantage: simpler design, easier excision for the surgeon, and removal of less healthy tissue
- disadvantage: notching or a gap can develop in the center of the defect where the 2 triangles peak
RHOMBIC/TANGENT-TO-CIRCLE EXCISION
- repair that is useful on the cheek and around the chin
- created by intentionally designing it with one side longer than the other.
- wound is closed by the rule of halves.
CURVED ELLIPSE
useful on **convex surfaces **such as the extremities where a linear repair may result in persistent standing cones or indentations
S-PLASTY
allows the length of a scar to be shortened
M-PLASTY
- Rather than extending the end of an ellipse or removing a Burow’s triangle, the redundant tissue may be excised inward, forming a M-shaped scar
- long axis of the incision is reduced by the length equivalent to the inverted triangle that makes the center of the M
*
This technique is useful for confining a scar to a single cosmetic unit or when an incision approaches a free margin.
M-PLASTY
- The scar may be camouflaged in locations where rhytides bifurcate, such as the crow’s feet in the periorbital area or around the lips.
- It is important to advance the inverted triangle up into the rest of the ellipse to take full advantage of the scar-shortening effect.
- A half-buried horizontal mattress suture, also known as a tip stitch, may help prevent necrosis of the central tip.
This closure is used when more extensive repairs are limited by lack of local tissue reservoirs or the patient’s health or coagulation status
PARTIAL CLOSURE
- The wound is closed from the ends toward the center. When wound tension prevents further closure, the area remains open to heal by second intention.
- The final scar is usually linear and may resemble a spread scar in the middle.
This is typically used to minimize the length of the final scar in large circumference neoplasms that are benign or low risk.
SERIAL EXCISION
Used when the length of an ellipse required to excise a lesion with a 3 or 4:1 ratio is too long for an acceptable cosmetic or functional outcome
SERIAL EXCISION
- A partial excision is performed, ideally an ellipse that accommodates the full length of the lesion, with primary linear closure.
- During the following months, the surrounding tissue stretches and the tension in the area decreases.
- Additional excisions are performed in a similar manner, removing the remaining lesion as well as the scar or scars created from the first steps of the procedure.
areas that heal well with secondary intention
Wounds located in concave areas such as the medial canthus, ear concha, alar crease (if small), temple region, and postauricular sulcus lend themselves well to healing by secondary intention
contributes to approximately 50% to 70% of the final wound closure and scar tissue fills out the remaining wound
Contraction
most important factor for cosmetic result
scar location, specifically contour of the lesion location
portion of full-thickness skin and subcutaneous tissue transferred from an adjacent donor site into the surgical defect
local skin flap
This flaps depend on a named artery for their blood supply
Axial pattern flaps
Flaps that is most widely used in dermatologic surgery. They are supported by the small arterioles and capillaries of the subdermal vascular plexus found in the mid-to-superficial fat.
random pattern flaps
The maximal flap length is determined by what?
vascular supply, not simply pedicle width
arrange the types of flaps from greatest to least perfusion pressure
- Axial pattern flaps
- Musculocutaneous flaps
- Fasciocutaneous flaps
- Random pattern flaps
n general, random pattern flaps on the face should have a maximal length-to-width ratio of?
3:1
This is however only a rough guideline, and individual patient characteristics such as tobacco use, sebaceous nature of skin, prior radiation or surgical procedures, and precise location all affect vascular perfusion.
To help ensure flap survival, the pedicle length-to-width ratios should not exceed what ratio on the trunk and extremities?
2:1
what type of flap are advancement flaps
All advancement flaps are random-pattern flaps; they do not rely on a specific named vessel, but rather adequate tissue laxity, for survival
double, parallel incisions are made tangential to what is most often a round defect
U-plasty
The flap is undermined, advanced into the defect, and secured with sutures, creating a U-shaped scar
single tangent flap where an incision is made at one end of a defect extending outward for some length, and the tissue mobilized is then advanced into the defect
L-plasty or A-to-L or O-to-L advancement
- used to repair medium-to-large defects of the medial cheek and/or lateral nose
- incision may be placed in the alar crease or nasolabial fold by removing tissue above and below the defect to allow the cheek to advance into the nasofacial sulcus
cheek advancement flap
2 sets of parallel incisions are made symmetrically on both edges of the defect, a bilateral advancement flap
H-plasty
This flap is essentially a bilateral U-plasty and is occasionally used on the forehead, eyebrow, glabella, and upper lip to hide incision lines along relaxed skin tension lines and cosmetic unit junctions.
This flap is essentially a bilateral O to L flap
O-to-T flap/ A-to-T or a T-plasty
The standing cone is removed from one end of the defect, creating a triangle, or transforming an “O” into an “A.” Single incisions extend from the base of this triangular defect, and the 2 sides of the triangle slide together along this baseline. This flap allows for redistribution of tension to 2 advancing edges.
best performed with the broad base along a free margin or cosmetic unit junction (eg, lip, eyebrow)
O-to-T flap/ A-to-T or a T-plasty
utilizes the removal of a small crescent of tissue along an advancement flap to either better hide the scar line or increase the length of the line to prevent distortion
CRESCENTIC ADVANCEMENT FLAP
This flap is particularly useful for the repair of upper lip and perialar defects.
CRESCENTIC ADVANCEMENT FLAP
may be considered as a variation of an advancement flap that has had all of its connections to the epidermis and dermis severed, maintaining its blood supply through a subcutaneous tissue pedicle
V-TO-Y FLAP (FORMERLY REFERRED TO AS AN ISLAND PEDICLE FLAP)
advancement flap used for small to medium-sized defects (up to 1.5 cm) of the lateral nasal supratip
EAST-WEST FLAP
- Two triangles are removed in the vertical axis.
- The superior one is adjacent to the defect and parallel to the long axis of the nose.
- The inferior triangle is midline, toward the columella.
- Removal of both triangles allows for an easy lateral sliding movement and closure.
superior based advancement flap for large defects on the nasal dorsum
Rintala flap
- A rectangular flap from the nasal dorsum and glabella is elevated in the supraperiosteal plane and advanced downward to cover the defect.
- Burrows triangles are created proximal to the alar groove or on the forehead.
- Thorough undermining must be performed to avoid nasal tip elevation.
skin moves into the defect by rotating around a pivot point
rotation flap
This is classically used to close relatively large defects on the cheek, temple, or scalp.
The ideal arc of a rotation flap extends up to how many times the width of the defect and makes up approximately one-quarter of the circumference of a circle?
5x
this flap is employed to repair nasal defects involving the distal dorsum or tip
DORSAL NASAL ROTATION FLAP AKA RIEGER FLAP
- The tissue reservoir of the nasal root and glabella allows for the movement of the dorsal nasal skin superior to the defect.
- A long, sweeping arc is created that extends into the nasofacial sulcus and terminates in the glabella.
- A back cut in the glabella improves the rotational mobility of this flap and is termed a hatchet flap
tissue is rotated into a defect from 2 opposite sides
BILATERAL ROTATION FLAP
- The vectors of rotation may be mirror images of each other, recapitulating the premise of the A–T advancement flap.
- This may be utilized for large defects on the scalp and larger defects on the lower lip
rotation flaps that can help prevent ectropion
Mustarde flap and the modified Tenzel flap
rotation flap useful for larger defects on the lower lid/periorbital cheek
Mustarde flap
- The flap extends laterally from the defect, arches superiorly to the lateral canthus and temple and ends in the preauricular area.
- The flap is undermined extensively and transposed over the defect.
semicircular flap for a lower lid defect that rotates the skin and orbicularis muscle from the lateral canthal area
Tenzel flap
- Additionally, the lateral canthal tendon is cut for increased tissue mobility.
- Both of these flaps must be anchored to the periosteum at the lateral orbital rim to help minimize downward tension on the eyelid and risk of ectropion
shown to be effective for the reconstruction of small to medium-sized partial thickness defects of the nasal ala and inferior nasal sidewall
SPIRAL FLAP
- It is a modified rotation flap with a 180° arc.
- The tip is advanced and rotated into the wound and sutured into the proximal aspect of the wound, the body of the flap follows creating a spiral
- With this flap, the cosmetic unit is preserved, there is no shortening of the nasal ala, and a standing cone does not form, therefore decreasing the risk of alar distortion
It is a modified rotation flap with a 180° arc.
SPIRAL FLAP
a random pattern flap, which borrows skin laxity from an adjacent area to fill a defect in an area with little or no skin laxity
transposition flap
Their primary function is to redistribute and redirect tension
Transposition flaps
This is useful in the closure of defects which would otherwise close under high tension or distort a nearby anatomical structure leading to functional or aesthetic impairment
Transposition flaps
One of the major advantage of these flaps is that they utilize adjacent skin and provide an excellent color and textural match.
Transposition flaps
most common transposition flaps in cutaneous surgery
rhombic flaps (and their variations), bilobed flaps, and banner flaps such as the nasolabial flap
designed by conversion of the primary defect into a 4-sided parallelogram with each side of equal length and tip angles of 60° and 120°
Rhombic flap
- designed to create a secondary defect perpendicular to the primary defect
- When closed, it would not only provide tissue to the primary defect, but also redirect the tension vector by 90°
- This rhombus forms the recipient site for the flap as well as the template on which to plan the flap incisions.
This modification differs from the classic rhombic transposition flap in that it utilizes a narrower flap tip angle and a shorter arc of rotation, allowing easier closure of the secondary defect, and some sharing of the tension between the primary and secondary defects.
DuFourmentel Flap
- modification of the classic rhombic flap utilizes a more acute angle than other rhombic transposition flaps, allowing for even greater tension sharing between the primary and secondary defects
- distal tip angle is designed to be 30°
30o-Angle Webster Flap
- This modification is used in situations where a fair amount of laxity exists in the horizontal axis of the rhombic shaped defect.
- The most common areas they are employed include the nasal dorsum, nasal sidewall, medial and lateral canthus, lateral forehead, temple, cheek, perioral region, inferior chin, and the dorsal hand.
This flap is most commonly planned as a melolabial transposition to repair defects of the nasal ala or from the pre- or postauricular area to close defects on the ear.
THE BANNER FLAP
more complex repairs that import pedicle-based tissue from a site distant to the defect
INTERPOLATION FLAPS
They are typically used on defects that are either too wide or too deep to reconstruct with local flaps or grafts
what artery is paramedian forehead flap based on?
Supratrochlear artery
Tissue is mobilized from the forehead, based on one of the supratrochlear arteries, and transposed to repair large distal nasal defects with the pedicle remaining attached in the glabellar region
PARAMEDIAN FOREHEAD FLAP
This flap is used to repair complex defects of the ala, particularly in instances when cartilage grafting is also required to restore the structural integrity of the alar rim.
The flap is harvested from the medial cheek and nasolabial fold and is based on branches of the angular artery
NASOLABIAL INTERPOLATION FLAP
what artery is NASOLABIAL INTERPOLATION FLAP based on?
branches of the angular artery
- employed when the defect involves the entire ala
- The motion of this flap is an upward rotation, opposite of the traditional nasolabial interpolation flap
reverse nasolabial flap, also known as a Spear’s flap
- reserved for repair of large, deep defects, typically of the upper lip
- It is particularly useful for defects that involve up to half of the lip without crossing the midline and those that penetrate into the muscularis.
Abbé flap is also known as the lip-switch flap
- harvested from the ipsilateral lower lip and is based on the inferior labial artery
what artery is Abbé flap/ lip-switch flap based on?
inferior labial artery
the pedicle of interpolation flaps remain in place for how long?
3 weeks
interpolation flaps are what type of flaps?
Axial flaps
This flap is a 2-staged interpolation flap useful for large defects of the helix
Retroauricular flap
- This flap is considered a random flap as it is not based on a large named artery.
- It is harvested from the richly vascularized skin of the postauricular scalp and is advanced over intervening intact skin to fill the helical defect; the pedicle remains attached to the posterior scalp
transplanted skin from a donor to recipient site with the goal of closing a surgical defect or wound
Skin grafts
what are the 3 basic types of skin grafts
- full-thickness skin grafts (FTSG),
- split-thickness skin grafts (STSG),
- composite grafts
These grafts consist of epidermis with full-thickness dermis and preserved adnexa
full-thickness skin grafts (FTSG)
These graft consist of epidermis with partialthickness dermis with loss of adnexa
split-thickness skin grafts (STSG)
full-thickness skin grafts with cartilage attached to the graft
Composite grafts
what are the classification of skin grafts according to donor origin
- autografts (donor = recipient)
- allografts (human to human)
- xenografts (animal to human)
What are the stages of wound healing in grafts?
- ** Plasma Imbibition:** First 24 hours—plasmatic imbibition or ischemia: the graft affixes to the recipient bed via fibrinous material
- Inosculation: 48 to 72 hours—anastomosis and proliferation of preexisting vessels of the graft and recipient wound base
- Revascularization: 4 to 7 days—growth and proliferation of vessels from the base. Blood and lymphatic flow begin, leading to the reestablishment of full circulation.
- Reinnervation: 2 weeks to 1 year—sensory reinnervation occurs from the periphery to the center of the graft, and may never be fully restored.
Identify the stage of healing in skin graft.
First 24 hours—plasmatic imbibition or ischemia: the graft affixes to the recipient bed via fibrinous material
Plasma Imbibition
Identify the stage of healing in skin graft.
48 to 72 hours—anastomosis and proliferation of preexisting vessels of the graft and recipient wound base
Inosculation
Identify the stage of healing in skin graft.
4 to 7 days—growth and proliferation of vessels from the base. Blood and lymphatic flow begin, leading to the reestablishment of full circulation.
Revascularization
Identify the stage of healing in skin graft.
2 weeks to 1 year—sensory reinnervation occurs from the periphery to the center of the graft, and may never be fully restored.
Reinnervation
Type of graft useful for defects in which complex linear closures or a flap would not be suitable, where close monitoring of the site is advisable, and in certain areas where they provide optimal aesthetic reconstruction
FULL-THICKNESS SKIN GRAFTS
When possible, FTSGs are chosen over STSGs because of their similarity in thickness and texture to surrounding skin and their relative lack of significant wound contraction.
generally result in a depressed, hypopigmented, scar without normal epidermal texture, they are reserved for larger wounds that cannot be covered with FTSGs
STSGs
grafts coming from this area can be used to repair most nasal defects
Preauricular skin
It has similar sun exposure and skin quality, and heals with minimal scar visibility
grafts coming from this area are particularly well matched for **nasal tip and alar defects **because of the similarity in texture and concentration of sebaceous glands as well as the ability to allow the donor site to heal by secondary intention
Conchal bowl
Common donor sites for larger defects on the scalp and forehead
supraclavicular region, lateral neck, or inner arm.
determines the chance of survival of the graft on a poor vascular bed
amount of dermis present
main advantage of an STSG
survives even in locations with poor vascularization, such as over bone or cartilage
It also allows for early detection of tumor recurrence. Cosmetically, the final outcome of this graft is suboptimal with absent appendages, poor color match, and frequent wound contracture under the graft.
Donor sites for composite grafts
helix and conchal bowl
composite grafts should remain less than how many cm2 , as a larger graft will not receive sufficient nutrients to allow its central portion to survive
2 cm2
These grafts have the highest metabolic demand and therefore the highest rate of failure
Composite grafts
Free cartilage grafts consist of?
cartilage and perichondrium
These grafts are commonly used to reconstruct defects on free margins such as the nasal tip, nasal ala, ear, and eyelid
Free cartilage grafts
Tissue that has been cultured or processed prior to grafting
skin substitute
