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T. Quinn and S. Ch’ng
dermis and subcutaneous fat and stronger ligaments, which retrain fat pads in their original
locations. The resulting fuller cheeks and
smoother face make scars more difcult to disguise. With age, the volume of skin, fat and even
bone decreases and the subcutaneous fat herniates over lax ligaments and fascia. The increased
prominence of rhytids and increased skin and soft
tissue laxity lend exibility to surgical planning
and tissue manipulation.
7.4.2 SMAS
The supercial musculoaponeurotic system
(SMAS), described by Mitz and Peyronie in 1976
[3], is a layer of brous tissue that invests the
underlying facial muscles and connects them
with the dermis, translating muscle movement
into visible facial expressions. It is continuous
inferiorly with the platysma, laterally with
parotid fascia, in the temple region with the
supercial temporal fascia and with the galea
aponeurotica over the scalp. Crucially for the surgeon, it acts as a barrier between skin and the
branches of the facial nerve. A surgeon who stays
supercial to the SMAS is unlikely to injure this
crucial structure. Tumours invading through
SMAS clinically appear xed and relatively
immobile, and the excision of such lesions should
not be undertaken without a sound understanding
of the anatomy of the facial nerve. Equally,
examination of the function of the facial nerve
should be a part of the assessment of these
tumours.
7.4.3 Facial Muscles
The muscles of facial expression are all supplied
by the facial nerve, which runs within the substance of the parotid. With the exception of the
deepest layer of facial muscles (buccinator, levator anguli oris, and mentalis), the muscles are all
supplied from their deep surface. As stated earlier, the pull of the facial muscles determines the
orientation of the rhytids. As such, an understanding of the location and orientation of the
facial muscles will aid in determining the placement of incisions.
7.4.4 Blood Supply
There are two important concepts to understand.
First is the anatomy of the major vessels of the
head and neck. These vessels form a complex
anastomotic network, which makes the head and
neck a uniquely well-vascularised region. A
sound knowledge of not only the course of the
arterial supply of the head and neck, but also the
layer in which it runs, is crucial to success.
The second concept is that of the angiosome,
as described by Taylor etal. [4], which states that
a given area of skin is supplied by a perforating
vessel. When raised, a ap can capture the adjacent angiosome, and so a random pattern ap
with a 2:1 length-to-width ratio can be raised
with some condence. However, if this is to be
exceeded, such as in a transposition ap of the
scalp, then the ap must incorporate a named
vessel or be delayed to ensure complete ap
survival.
Professor Taylor also described the concept of
delay, which describes a technique of temporary
incomplete division of a ap’s blood supply,
which allows vasodilation of ‘choke vessels’
between angiosomes, thus allowing the capture
of the territory of a third angiosome [5]. Delay
refers to waiting at least 72hours, though often
closer to a week, before completion of ap division to ensure that these choke vessels are completely and permanently dilated. The delay allows
for a longer, larger ap to be raised when it is not
possible to incorporate a named vessel within the
ap.
7.4.5 Nerves
The sensory supply of the face comes from
branches of the trigeminal nerve, whereas the
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95
motor supply comes from the facial nerve. An
understanding of the sensory supply is extremely
useful when administering local anaesthetic.
Many local ap procedures can be done under
local anaesthetic, with or without sedation. Not
only does this allow for quick surgical turnover, it
is, more importantly, a safe technique for skin
cancer patients who, in general, are elderly and
may have multiple comorbidities. It is possible to
anaesthetise large areas of the head and neck with
only a few injection sites. For example, the entire
nose can be blocked with three injections– the
infratrochlear nerve, the external branch of the
anterior ethmoidal nerve and the infraorbital
nerve.
A three-dimensional understanding of the
anatomy of the facial nerve is absolutely crucial
in order to avoid inadvertent injury to its many
branches. The facial nerve is deep to the SMAS
layer, and staying above this plane is generally
safe. However, the SMAS can be surprisingly
supercial in certain areas, particularly in the
temple region and over the mandible where the
frontal branch and the marginal mandibular
branch of the facial nerve are at risk of injury.
Care should also be taken not to inject longacting anaesthetics in these areas as even a temporary facial paralysis can cause signicant
anxiety to both patient and surgeon.
7.5 Non-Surgical Management
Oncologically, non-surgical management should
only be used for the treatment of supercial
lesions such as supercial BCC or solar keratoses
and in situ SCC. The choice of surgery versus
non-operative management should be a joint
decision between the clinician and the patient as
they can be labour-intensive and potentially less
effective than surgery. All lesions should be biopsied prior to non-surgical treatment in order to
conrm the diagnosis. It is not unheard of that
metastatic melanomas have been diagnosed with
the only evidence of a primary lesion being one
that had been previously treated topically by a
well-meaning but misguided clinician.
7.5.1 Topical Creams
Topical therapies included 5% 5-uorouracil
(5-FU) ointment, approved for use in solar keratoses and SCC in situ, and 5% imiquimod ointment, which is used for supercial BCCs. These
ointments require daily to twice daily application
for up to 6weeks.
Imiquimod stimulates innate and cellmediated immune responses to tumour antigens,
which activate cytokines such as tumour necrosis
factor-alpha (TNF-a), interleukins and interferonalpha (IFN-a). This inhibits angiogenesis and
promotes apoptosis in tumour cells. 5-FU is an
antimetabolite, which blocks thymidine synthesis
and induces cell cycle arrest and apoptosis.
Both cause signicant inammation during
the course of treatment, which improves following cessation of application. Follow-up is recommended at least 4–6 weeks after treatment is
complete so that settling inammation is not confused with residual tumour. Lesions that are
resistant to topical therapy should be excised.
7.5.2 Cryotherapy
Cryotherapy can be used in similarly supercial
lesions and involves the application of liquid
nitrogen. It can be applied either via a cotton
swab dipped in liquid nitrogen or, preferably, in
spray form. Depending on the lesion, the liquid
nitrogen is applied for 15–30s and should include
the lesion and an additional 1–2mm margin. The
extent of tissue injury is proportional to the rate
of freezing and thawing. In some cases, a second
application is recommended in which case the
area should be allowed to thaw completely before
liquid nitrogen is reapplied. Repeated freeze–
thaw cycles produce greater tissue damage due to
increased conductivity and impaired circulation
of previously frozen tissue. The mechanism of
damage comes from the physical damage of cellular components by ice crystals and osmotic
damage during thawing. Additionally, there is
immunologic stimulation due to the release of
antigenic components.
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T. Quinn and S. Ch’ng
Similarly, to other burn injuries, the area will
become inamed and may blister following treatment. The area then heals by secondary intention.
As with topical therapies, if the lesion has not
resolved by the time the area has healed, then surgical excision should be undertaken.
7.5.3 Photodynamic Therapy
Photodynamic therapy (PDT) is another option
for the treatment of supercial lesions. It is especially useful in cosmetically sensitive or extensive areas of disease where other surgical or
non-surgical options may not be suitable.
Photosensitising agents such as methyl aminolevulinic (MAL) cream are applied to the
lesion plus a 5 mm margin and an occlusive
dressing is applied and the cream is left in place
for three hours. The cream is then wiped clean
and light is then used to activate the photosensitising agent, resulting in the formation of cytotoxic reactive oxygen species. Various light
sources such as intense pulse light (IPL) or LED
light can be used. Peak absorption occurs at 410–
620 nm with longer wavelengths, resulting in
greater tissue penetration.
7.5.4 Radiotherapy
desquamation to skin or mucosal surfaces, swelling and inammation. Later effects, which can
occur months to years after treatment, include tissue brosis, dryness, alopecia, lymphoedema and
cancer. Younger patients in particular should be
counselled against radiotherapy due to the risk of
additional long-term consequences such as the
difculty in surgically managing an irradiated
eld in the case of recurrence and radiationinduced cancers such as angiosarcoma.
7.6 Surgical Management
7.6.1 Excision
Skin cancers need to be excised with an adequate
margin, which will depend on the type of malignancy. At a minimum, the full thickness of the
dermis and some underlying subcutaneous tissue
should be excised as a part of the specimen.
Excising the lesion to the next tissue plane is
oncologically indicated in most cases, and if
there are any signs that the lesion is more deeply
invasive, the next plane should be taken with the
specimen to ensure clearance. The lesion should
then be adequately oriented, conventionally with
a silk suture at 12 o’clock, so that the pathologist
can clearly state the margin of excision. This will
make re-excision, if it is required, more targeted.
Radiotherapy is another option, particularly for
patients who are not candidates for surgical
resection, either because the disease is too extensive or because their comorbidities preclude surgery. Additionally, patients who do not wish to
have surgery in order to avoid scars can elect to
undergo radiotherapy though the potential cosmetic outcomes such as skin discolouration and
alopecia should not be underestimated.
Ionising radiation works by causing DNA
damage and thus inducing cell death. Depending
on the extent of the skin lesion being treated, the
dose (measured in greys, Gy) and fractions (number of sessions required) are adjusted by the radiation oncologist. Side effects of radiotherapy are
divided into acute and late. Acute effects include
7.6.2 Direct Closure
If there is adequate skin laxity following excision, then the wound can be directly closed. The
lesion should then be excised as an ellipse so that
the nal wound is a straight line. Alternatively, if
it is uncertain whether or not the wound can be
closed, the lesion can be excised with an appropriate margin and then the dog ears excised secondarily. To excise a dog ear, the edge of the
wound is elevated with a skin hook, or ne forcep, and the excess, triangular piece of skin is
excised in the desired direction. The nal incision
should lay parallel to a rhytid for the best cosmetic result.
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7.6.3 Skin Grafts
Almost any defect is amenable to skin grafting,
either split or full thickness. Grafts will take on
any bed with the exception of bare bone, cartilage
or tendon. Grafts are a good option for large
defects, where local aps are not possible or
where the cosmetic results are less obvious such
as in the conchal bowl or posterior ear. The main
disadvantage of a skin graft is that it is cosmetically less favourable than a local ap as the
colour match and the soft tissue contour are often
inferior than when using skin immediately adjacent to the defect.
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7.7 Local Flaps
Local aps can be classied depending on their
patterns of blood supply, the type of movement or
descriptive based on the design. For the sake of
simplicity, this section will focus on the aps
based on the location on the head and neck for
which they are most suited, either because of the
availability of tissue laxity or because the nal
scar sits within, or parallel to, existing rhytids.
There are myriad ways of reconstructing facial
defects with local aps, limited only by ones’
imagination but more importantly by the blood
supply. Described below are the most commonly
used aps for each anatomic subunit of the head
and neck.
7.7.1 Scalp
The scalp has a rich blood supply (Fig. 7.1)
thanks to ve pairs of vessels that anastomose
with each other. These vessels include the supraorbital, supratrochlear, supercial temporal, posterior auricular and occipital arteries. The galea
aponeurotica is a brous tissue layer, which is
continuous with the SMAS.Because of the density, it often acts as a good barrier to skin cancers
and forms a sound oncologic plane to all but the
thickest or deeply ulcerating tumours. Beneath
this, the pericranium is an excellent recipient bed
for grafting due to its rich blood supply. However,
Fig. 7.1 Blood supply of scalp
if the pericranium is excised as a part of the resection or if a hairless patch of skin on the scalp is
cosmetically unacceptable, various local aps
should be a part of any skin cancer surgeon’s
reconstructive armamentarium. All local aps of
the scalp are raised deep to the galea aponeurotica in a plane, which is relatively bloodless. The
underlying pericranium is left behind so that if
the secondary defect is unable to be closed, it can
still be grafted.
Ungraftable defects up to 3cm can be closed
with a rotation ap (Fig. 7.2). Slightly larger
defects may require a second rotation ap from
the opposite direction to close the defect. Rotation
aps work by redistributing the tension across a
longer incision. The incisions are all closed primarily, thus preserving hair, though it may be
thinned along the scar due to stretching of the
skin. A back cut may be required if the tension is
too great though this should be avoided due to the
potential risk of compromising the blood supply.
Ahuja etal. [6] described a modication of the
rotation ap using the principles of the transposition ap to minimise the need for this back cut.
The modication takes on some elements of a
transposition ap where the tip of the ap extends
beyond the edge of the defect, increasing the arc
of rotation and thus further reducing the tension.
Defects up to 6cm in size will usually require a
scalp transposition ap with grafting of the
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Fig. 7.2 Scalp rotation
ap
Fig. 7.3 Scalp
transposition ap
T. Quinn and S. Ch’ng
secondary defect (Fig.7.3). Because the length-towidth ratio exceeds 2:1, these need to be based on
at least one of the named vessels of the scalp. To
design the ap, the lesion is triangulated and this
whole area is excised to minimise the resultant dog
ear. The width of the ap must at least equal the
size of the defect and the tip of the ap extend
beyond the tip of the defect to ensure comfortable
closure of the defect without undue tension.
Larger defects of the scalp will require alternative approaches such as free tissue transfer, tissue expansion or the use of acellular dermal
matrixes.
7.7.2 Forehead
Advancement aps, which have incisions parallel
to the horizontally oriented rhytids of the forehead, are a good option for small defects of the
forehead that cannot be directly closed. If there is
insufcient laxity, then a second advancement
ap from the other side of the defect, also called
a H-ap due to the resulting scar, can be raised.
Defects immediately above the eyebrow can be
closed with an A-T ap, with the resulting horizontal limb of the scar laying parallel to the eyebrow thus preserving its shape (Fig.7.4).
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Fig. 7.4 Forehead
advancement and A-T
ap
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Fig. 7.5 Forehead
rotation aps 1 and 2
Larger defects can be closed with either a single large rotation ap or two rotation aps
(Fig. 7.5). These are incised along the hairline,
thus preserving this important anatomical land-
mark. The disadvantage is that these necessarily
cut the supraorbital and supratrochlear nerves,
resulting in numbness of the anterior scalp
(Fig.7.6).
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Fig. 7.6 Forehead
rotation aps 1 and 2
Fig. 7.7 Cross section
of temporal fascia
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7.7.3 Temple
When undertaking a resection of a lesion in the
temple region, it is absolutely crucial to have a
good understanding of the anatomy (Fig. 7.7).
Pitanguy’s line describes the surface landmark of
the frontal branch of the facial nerve. It is a line
that runs 0.5 cm below the tragus to a point
1.5cm above and lateral to the eyebrow. However,
this describes the course of the nerve in only one
plane. A favourite question of examiners is to
describe the fascial layers of this area and the
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way in which the frontal branch relates to it. In
the preauricular region, the SMAS splits to
encompass the parotid gland. These two layers
then coalesce over the zygomatic arch, to which
it is rmly adherent, to form the innominate fascia. The frontal branch is immediately deep to
this fascia and supercial to the periosteum of the
arch. Above the zygoma, the fascia splits into the
supercial temporal fascia, also known as the
temporoparietal fascia, and the deep temporal
fascia, which itself has two layers, supercial and
deep, which encase the temporal fat pad. These
two deep temporal fascial layers then merge and
become the fascia overlying the temporalis muscle. The supercial temporal fascia, being part of
the SMAS, continues into the forehead as the
frontalis muscle and into the scalp as the galea
aponeurotica.
The frontal branch of the facial nerve lies
immediately deep to the supercial temporal fascia and care should be taken not to breach this
layer when resecting a tumour. If there are suspicions that the tumour invades the fascia, then the
patient needs to be counselled that the nerve may
need to be sacriced in order to ensure oncological clearance, thus resulting in a brow palsy that
can be corrected at a later stage with a brow lift.
Even if the fascia is not breached, administration
of local anaesthetic into the area can cause a temporary nerve palsy, which the patient needs to be
warned about in order to minimise anxiety for the
patient and phone calls/questions to the surgeon.
There is often a reasonable amount of laxity in
the temple region, depending on the age and skin
of the patient and lesions up to 1–1.5cm can be
closed directly. The workhorse local ap for this
area is the rhomboid ap, a type of transposition
ap that borrows from the relatively abundant
transverse laxity to close moderately sized
defects. In choosing a rhomboid ap to close the
defect, the surgeon must ensure there is adequate
laxity from the donor site to close primarily. If
there is not, then an alternative such as a skin
graft should be considered, which, in this natural
hollow, can be cosmetically acceptable. With the
rhomboid ap (Fig.7.8), a transversely oriented
diamond is marked around the tumour and the
required margins. The obtuse angles should equal
120 degrees and the acute 60. The perpendicular
line is then marked extending from point C (see
diagram below), the length of which should be
equal to the distance between points A and B.The
ap is then raised supercial to the SMAS and
transposed into the defect. The donor site is then
closed primarily, resulting in a scythe-shaped
scar.
7.7.4 Nose
Being centrally located within the face, the nose
is particularly suited to ap reconstruction in
order to preserve cosmesis. Hatchet aps, which
are a combination of rotation and V-Y advance-
Fig. 7.8 Rhomboid ap
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T. Quinn and S. Ch’ng
ment, are a good option for closure of defects of
the nasal dorsum (Fig.7.9). Bilobed aps utilise
laxity available in the nasal dorsum and sidewall
to close defects of the relatively immobile nasal
ala (Fig.7.10).
Complex defects of the ala or tip may require
staged reconstruction with either nasolabial or
paramedian forehead aps. The nasolabial ap
(Fig.7.11) can be superiorly or inferiorly based
and rely on blood supply from the angular artery,
the continuation of the facial artery. The paramedian forehead ap, the rst description of which
dates back to around 700 BC when it was
described by the Indian physician Sushruta, is
based on either the supraorbital or more com-
monly the supratrochlear artery (Fig.7.12). The
nasolabial ap needs to be thick enough to capture the angular artery. The paramedian forehead
ap is typically raised in the subcutaneous plan in
the distal third, submuscularly in the central third
and subperiosteally in the proximal third to
ensure that the artery is captured within the ap.
Both nasolabial and paramedian forehead
aps require at least two procedures. The rst
stage involves raising and insetting the aps into
the defect. Once the blood supply is established
at the site of the defect, the pedicle can be divided,
usually 2–3weeks after the rst stage. Often, a
third stage is required to thin or rene the ap
prior to division, a process that is risky to do in
the rst stage as the already compromised blood
supply can be further threatened by thinning out
the tissue on which the skin depends for its survival. This intermediate stage should be at least
2–3 weeks after the rst stage to maximise the
blood supply. If the nasal defect is full thickness,
the ap can be folded on itself or its undersurface
grafted to reconstruct the mucosal surface of the
nose.
Fig. 7.9 Nose hatchet ap
Fig. 7.10 Nose bilobed ap
7.7.5 Lip
Defects between the nose and the upper lip are
usually best reconstructed with a full-thickness
graft as local aps will cross and disrupt the cosmetic subunits. Lesions involving the vermilion
are best excised as a full-thickness wedge, which
can be used for defects involving up to 30% of
either the upper or lower lip. Defects involving
up to 60% of the upper or lower lip can be reconstructed using a lip-sharing technique. The
advantage of this reconstruction is that the orbicularis can be reconstituted, thus ensuring its
continuity and function. For central defects, the
Abbe ap (Fig.7.13) can be based either medially or laterally. The contribution from the donor
lip should be half that of the defect, ideally no
more than 30% to ensure that the donor site can
be primarily closed. The Abbe ap is necessarily
a two-stage operation with ap division occurring 2–3weeks after the ap is inset. During this
time, mouth opening is restricted and the patient
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Fig. 7.11 Nasolabial ap
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Fig. 7.12 Paramedian forehead ap
will need to be on a liquid diet so consultation
with dietetics and speech therapy is crucial. The
Estlander ap (Fig.7.14) is for defects involving
the commissure and is always medially based. It
is theoretically a single-stage operation, but the
resulting blunting of the commissure may need to
be corrected with a commissuroplasty at a separate operation.
Large defects (75–100%) of the lip are challenging to reconstruct. The main issue is that of
microstomia and potential loss of oral compe-
tence due to disruption of the continuity of orbicularis oris. The Karapandzic ap involves
semicircular incisions extending down from the
nasolabial folds, which are then rotated in to
close the defect (Fig.7.15). Care is taken to preserve the neurovascular bundle of the lip to preserve both function and sensation. The
Bernard–Burrow–Webster ap uses laxity from
the cheek to reconstruct up to a total lower lip
defect (Fig.7.15). Burrow’s triangles are excised
from the nasolabial fold to allow advancement.
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