Applied surgical anatomy in relation to facial rejuvenation · 2021. 8. 20. · Applied surgical...
Transcript of Applied surgical anatomy in relation to facial rejuvenation · 2021. 8. 20. · Applied surgical...
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Applied surgical anatomy in
relation to facial rejuvenation
Name of the Doctor :-Dr. Manisha Nijhawan
• Points to be covered
• Introduction
• Anatomical zones of face
• Cosmetic units
• Skin tension lines
• SMAS
• Facial muscles
• Sensory nerves and vasculature
• CONCLUSION
• Introduction
surgical techniques for facial rejuvenation have
evolved tremendously over the last few
decades
proper surgical rejuvenation of the face can
restore the original anatomy , giving the face a
natural younger appearance
• Boundaries of face or Countenance
- superiorly to hair line, inferiorly to the chin &
the base of mandible & on each side of
auricle.
• Regional anatomy of the face
divided into 13 anatomic regions
• Cosmetic units of the face ( facial esthetic
units)
.these cosmetic units share similar color ,
texture , thickness and mobility of the skin
.these cosmetic units include
.forehead , the temple
cheeks , nose
periorbital area , lips , chin
.By placing incisions at the boundaries of these
subunits , final scars are visually minimized
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• NOSE
.The nose has the most subdivisions on the face.
.The horizontal root, which borders the glabella on the forehead, is positioned superiorly.
.The midnose contains the dorsum medially and is flanked by the 2 lateral sidewalls.
.The dorsum is inferiorly bordered by the tip, which ends in the columella ,the thin sliver of tissue that separates the nostrils on the underside of the nose.
.The tip is bordered by the ala nasi, or alae, on both sides, and the columella is flanked by the soft triangles, which also border the tip and the alae.
• Skin is thinnest at rhinion and thickness
increases towards the tip of nose
• Adequate antibiotic coverage must be given
when procedure done in this area
• EAR
external ear is composed of
skin and cartilage with
supporting nerves and vessels
During surgeries on the ear ,
following should be noted
1) Resection in pre and posterior auricular
areas can cause sensory denervation of ear
2) Field block of the skin around periphery of the auricle
provides adequate anesthesia
3) Deep infilteration just infront of the ear may result in
temporary paralysis of the facial nerve
• Lips
The lower part of the face is dominated by the subunits of the
lip.
Below the nose, in the moustache area, are the cutaneous
regions of the upper lip, which are separated from the cheek
by the nasolabial fold.
The middle depression below the nose, known as the philtrum,
is an important anatomic subunit, because even minimal
displacement of this structure results in significant
disfigurement.
The lips constitute the vermilion subunit. The cutaneous lower
lip, which borders the chin inferiorly and is bound by the
nasolabial fold laterally, is below the vermillion.
• Eye
The eyelid is a complex structure with multiple subunits.
The largest component of the eyelid is the orbital portion, which
borders the eyebrow superiorly and the cheek inferiorly.
Just below the eyebrow is the preseptal area and then the
pretarsal portion, where the eyelashes insert.
Additional components of the eyelid include the superior
palpebral fold, the palpebral fissure, the medial limbus, and
the medial canthus
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• The skin of the eyelids is the thinnest of the
body
• Fat is very sparse in preseptal and preorbital
skin and is absent from pretarsal skin
• S.c tissue is absent over the medial and lateral
palpebral ligaments
• Skin tension lines
.Skin tension lines (STLs) are the
result of a complex interaction
between internal and external
factors involving the skin.
.The intrinsic framework, which
consists of elastin and collagen,
progressively loosens with age.
Its interaction with the muscles
of facial expression leads to the
development of STLs.
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• Generally, STLs are perpendicular to the underlying muscles of
the face. Aging, particularly photoaging, tends to accentuate
the appearance of STLs.
• In the repair of STLs, the correct placement of the long axis of
an excision parallel to the STLs results in better scar cosmesis.
• Furthermore, flaps should be placed to allow the suture lines
to fall in STLs. nearly everyone has horizontal STLs.
• Superficial Musculoaponeurotic System
The facial musculature must work synergistically to
allow for a wide range of facial expressions. The
superficial musculoaponeurotic system (SMAS) is a
discrete fibromuscular layer that envelops and
interlinks the muscles to provide these synergies
• The SMAS is generally located beneath the subcutaneous fat
and is superficial to the muscles.
• In addition, the SMAS serves as a useful marker in assessing
the location of vital blood vessels and nerves. The superficial
portion of the SMAS generally houses the axial blood vessels
and sensory nerves, whereas the deeper levels contain the
more vital motor nerves
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• Muscles of Facial Expression
The muscles of facial expression are unique in a number of
ways.
Rather than inserting into bones or tendons, all of the muscles of
facial expression originate from or insert into the skin.
They are all derived from the second embryonic branchial arch
and are innervated by the seventh cranial (facial) nerve.
Different anatomic areas of the face have synergistic and
antagonist groups of muscles that enable individuals to make
varied facial expressions.
• Muscles affecting the forehead and eyebrow include the
frontalis muscle, which creates the horizontal wrinkles on the
forehead and assists with eyebrow elevation, and the
corrugators and procerus muscles, which are antagonistic
muscles on the forehead.
• The orbicularis oculi muscles are a complex of muscles
surrounding the eyes; these assist with closing the eye tightly.
This complex lies superficially in the eyelid skin and is
encountered with even a shallow incision.
• The dominant muscle of the nose is the nasalis muscle, which
consists of nasal and alar components. Its function is to
compress and dilate the nares.
• Mouth muscles
The mouth has the most extensive network of facial
musculature and accounts for much of an individual's
capability of facial expression.
The orbicularis oris encircles the mouth and is the major
component of the lips.
The major functions of the orbicularis oris muscle are to
pull the lips against the teeth, to draw the lips together,
to pull the corners of the mouth together, and to pucker
the mouth.
This muscle is also extremely important for the phonation
of sounds that rely on the lips, such as the pronunciation
of the letters M, V, F, and P.
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PRACTICE USING FACIAL
MUSCLES SELECTIVELY IN
FRONT OF MIRROR
Common Facial Expressions
• Smiling & Laughing: Zygomatics Major• Sadness: Levator Labii Superioris and Levator
Anguli Oris• Grief: Depressor Anguli Oris• Anger: Dilator Naris & Depressor Septi• Frowning: Corrugator Supercilii & Procerus• Horror, Terror & Fight: Platysma• Surprise: Frontalis• Doubt: Mentalis• Grinning: Risorius• Contempt: Zygomatic Minor
SMILING MUSCLES FROWNING MUSCLES
• Orbicularis Oculi: close eyelid
• Nasalis: compress/dilate nasal openings
• Levator Labii Superioris: raise upper lip
• Levator Anguli Superioris: raise angle of mouth upward
• Zygomaticus: draw angle of mouth upward
• Risorius: draw angle of mouth laterally
• Frontalis: elevate eyebrows
• Orbicularis Oris: closes mouth
• Depressor Anguli Oris: draw angle of mouth downward
• Depressor Labii Inferioris:lowers lower lip
• Mentalis: draws chin up
• Platysma: draws lower lip down & back
• Sensory Nerves
The trigeminal nerve, or cranial nerve (CN) V, is primarily
responsible for the sensory innervation of the face.
The cervical, facial, glossopharyngeal, and vagus nerves have
smaller contributions.
The sensory nerves are typically located more superficially than
the motor nerves, along the junction of the fat and the SMAS.
Transection of the sensory nerves does not result in the serious
morbidity that motor nerve damage causes, and the recovery
of sensory function after such injury is typical.
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• The trigeminal nerve is divided into 3 branches: ophthalmic
(CN V1), maxillary (CN V2), and mandibular (CN V3). Ophthalmic Ophthalmic
NerveNerve
BRANCHES:
The ophthalmic nerve contributes several branches to the
upper eyelid, the forehead and scalp, and the external nose.
EJ1
Maxillary Maxillary
NerveNerve
BRANCHES:
On the face, the infraorbital nerve breaks up into three sets
of branches.
EJ2
Mandibular Mandibular
NerveNerve
BRANCHES:
The cutaneous contribution of the mandibular nerve to the
face is fairly widespread.
EJ3
• The cervical plexus lies deep to the sternocleidomastoid
muscle.
• The plexus provides sensation to several important structures
and is derived from C2 through C4.
• These nerves include the great auricular (C2, C3), lesser
occipital (C2), greater occipital (C2), third occipital (C3),
transverse cervical (C2, C3), and supraclavicular nerves.
• They send sensory fibers to the neck, posterior part of the ear,
and postauricular scalp.
• The spinal accessory and cervical nerves emerge near the Erb
point in the posterior triangle on the neck and are easily
damaged during cutaneous surgery
• Sensory branches of the vagus, glossopharyngeal, and facial
nerves innervate the skin of the external auditory canal, the
concha, and the posterior sulcus.
• Awareness of the sensory branches of the face allows the use
of nerve blocks, which provide effective anesthesia with
minimal discomfort for the patient. Mental, infraorbital, and
supraorbital blocks are easily achieved after the identification
of their respective foramina, which lie in the midpupillary
plane
Slide 32
EJ1 • The Ophthalmic is the smallest, uppermost sensory branch from the Trigeminal n. It gives offthree branches before exiting the orbit: the nasociliary, frontal and lacrimal nerves).• The Nasociliary branch gives rise to the infratrochlear, and external nasal nn. These innervate the nose and medial canthus.• The Frontal Branch splits into the Supratrochlear, and Supraorbital nn. which together supply sensory innervation to the frontal scalp, forehead, upper eyelid.• The lacrimal n. innervates the lateral eyelid.Eric Jewell, 18-09-2013
Slide 33
EJ2 • The Maxillary branch of the trigeminal nerve forms the infraorbital, zygomaticofacial and zygomaticotemporal cutaneous sensory branches.• The infraorbital neurovascular bundle emerges from the infraorbital foramen to provide significant sensory innervation to the medial cheek, upper lip, nasal sidewall and ala, and the lower eyelid.• Lateral to the infraorbital foramen, the zygomaticofacial nerve emerges to innervate the skin of the malar eminence.• Cutaneous innervation of the temple and supratemporal scalp region is provided by a third branch of the maxillary division, the zygomaticotemporal nerve. It emerges from the lateral orbital margin at the zygomatic bone. • The superior alveolar and palatine nerves are deeper branches of V2 that provide sensory innervation to the upper teeth, palate, nasal mucosa, and gingiva.Eric Jewell, 18-09-2013
Slide 34
EJ3 • The mandibular branch (V3) is the largest division of the trigeminal nerve and the only one tocarry both cutaneous sensory and motor fibers. The auriculotemporal, buccal and inferior alveolar nerves represent the three main cutaneous branches of V3.• The auriculotemporal nerve travels up towards the lateral scalp. It provides sensory innervation to the external ear and auditory canal, temple, temporoparietal scalp, TMJ, and tympanic membrane. It also caries parasympathetic fibers to the parotid gland.• The buccal nerve runs deep to the parotid gland then pierces the upper surface of the buccinator. It innervates the cheek, buccal mucosa, and gingiva. Because the terminal branches of the buccal nerve are small and numerous, regional buccal nerve blocks are difficult.• The inferior alveolar branch of V3 innervates the mandibular teeth as it courses through the mandibular canal. Its terminal branch forms the mental nerve, which emerges from the mental foramen to innervate the skin, mucosa, and gingiva anterior to the foramen.• The lingual nerve supplies sensory innervation to the anterior two-thirds of the tongue, the floor of the mouth, and the lower gingivae. It arises from V3 and courses parallel and superior to the inferior alveolar nerve.Eric Jewell, 18-09-2013
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Main Branches of Main Branches of External CarotidExternal Carotid• SUPERFICIAL TEMPORAL ARTERY
• MAXILLARY ARTERY
• TRANSVERSE FACIAL ARTERY
• FACIAL ARTERY
• LINGUAL ARTERY
Main Branch of Main Branch of Internal CarotidInternal Carotid• OPHTHALMIC ARTERY
EJ [2]1
•• SUPERFICIAL TEMPORAL ARTERYSUPERFICIAL TEMPORAL ARTERY–– ORIGIN:ORIGIN: External Carotid Artery
–– COURSE:COURSE: Ascends anterior to ear, to temporal region and ends in the scalp.
•• MAXILLARY ARTERYMAXILLARY ARTERY–– ORIGIN:ORIGIN: External Carotid Artery
–– COURSE:COURSE: Passes anteriorly between ramus of mandible and sphenomandibular ligament within infratemporal fossa. Passes either superficial or deep to lateral pterygoid unitl reaching pterygopalatinefossa.
•• TRANSVERSE FACIAL ARTERYTRANSVERSE FACIAL ARTERY–– ORIGIN:ORIGIN: Superficial temporal artery
–– COURSE:COURSE: Crosses face external to the masseter and inferior to the zygomatic arch.
•• FACIAL ARTERYFACIAL ARTERY–– ORIGIN:ORIGIN: External Carotid Artery
–– COURSE:COURSE: Ascends deep to the submandibular gland, winds around the inferior border of the mandible and enters the face.
•• LINGUAL ARTERYLINGUAL ARTERY–– ORIGIN:ORIGIN: External Carotid Artery just inferior to facial
artery.
–– COURSE:COURSE: Passes deep to the posterior belly of the digastric and sylohyoid mm. Passes deep to the hyoglossus m. and anteriorly between the hyoglossus and genioglossus mm.
EJ4
OPHTHALMIC ARTERYOPHTHALMIC ARTERYFROM INTERNAL CAROTID ARTERY
• SUPRATROCHLEAR
• SUPRAORBITAL
• LACRIMAL
• EXTERNAL NASAL
• DORSAL NASAL
EJ5
• Venous system
• The venous network of the face parallels the arterial system.
Unlike the arteries, the veins tend to be straighter and less
tortuous.
Applied anatomy of facial vasculature
. Important while performing soft tissue augmentation using
dermal fillers , its complication include skin necrosis due to
interruption of vascular supply
. Direct arterial embolization of filler material will generally cause
immediate skin blanching ( pain)
. Venous occlusion can occur if excessive amounts of filler are
placed in a small area leading to venous congestion
• Cutaneous Anatomy of the Neck
The key cutaneous muscles of the neck are the platysma and
sternocleidomastoid muscles.
The platysma is covered by the SMAS, which is continuous with
the lower muscles of the face, and it is also considered a
muscle of facial expression.
The platysma is an extremely thin muscle that is superficial in
the neck.
The sternocleidomastoid muscle extends from the medial
clavicle to the postauricular area and divides the neck into
posterior and anterior triangles.
Slide 38
EJ [2]1 • Most of the arterial supply to the face arises from the superficial temporal artery and facial branches of the external carotid.• The maxillary branch of the external carotid supplies most areas that the superficial temporal and facial branches do not supply.• The internal carotid artery supplies the anterior portion of the forehead and dorsal surface of the nose via ophthalmic artery branches.Eric Jewell, 19-09-2013
Slide 39
EJ4 • The superficial temporal artery is 1 of 2 terminal branches of external carotid. It gives rise tothe transverse facial a. before exiting the parotid gland. The superficial temporal supplies many of the facial muscles and skin of the frontal and temporal areas.• The maxillary artery is the other terminal branch of external carotid. It has many branches, but the main branches supplying blood to the face are the infraorbital, buccal and mental arteries.• The transverse facial artery is a branch of the superficial temporal artery. It supplies branches to the parotid gland and duct, some branches to the masseter muscle, and cutaneous branches to overlying skin.• The facial artery is the major blood supply for the face (both skin and muscles of facial expression). It’s branches are the lateral nasal, superior & inferior labial, and submental arteries – and it terminates at the angular artery.• The lingual artery branches off from the external carotid just inferior to the facial artery. It supplies the tongue.Eric Jewell, 06-09-2013
Slide 40
EJ5 • The ophthalmic artery arises from the internal carotid within the middle cranial fossa. It enters the orbit thru optic foramen, and crosses the optic nerve to the medial part of orbit. Within the orbit it give rise to it's 5 major branches:• The Supratrochlear, Supraorbital, Lacrimal, External Nasal, and Dorsal Nasal branches.• These branches supply blood to the muscles of the eye, the retina, upper eyelids, external nose, forehead, anterior scalp, and lacrimal gland.Eric Jewell, 11-09-2013
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• Key components of the anterior triangle include the internal
and external carotid arteries, the internal jugular vein, and the
vagus and hypoglossal nerves.
• The important structure to consider to the posterior triangle
is the spinal accessory nerve (CN XI), which innervates the
sternocleidomastoid and trapezius muscles.
• Transection of the spinal accessory nerve results in a winged
scapula and difficulty with arm abduction.
• Also found in the posterior triangle is the superficial cervical
plexus, which has sensory, motor, and sympathetic functions.
• Skin tension lines
• STLs typically lie in a transverse direction on the neck. The
placement of excision lines in this orientation is essential,
because hypertrophic or reddened scars often result from
misplaced excisions on the neck
• Anatomic Surgical Considerations
• Free margins are located on the eyelids, helices of the ears, lips, and alar rim and columella. Unopposed tension caused by a surgical repair may distort these structures. Wound closure in these locations often require flap and/or graft placement to lessen the risk.[3]
• When designing flaps, borrow tissue from the same or adjacent cosmetic units to minimize anatomic distortion and maximize tissue match.
• A reservoir of skin for flaps or primary closure can be found on the lower and posterior part of the cheek near the angle of the mandible. In older persons, this area is the jowl. Other areas with redundant skin include the preauricular aspect of the cheek, the temple, and the neck.
• Place the suture lines along STLs and on the boundaries of the
cosmetic units whenever possible.
• Preoperatively identify the vital structures that might be
damaged in the operative field, and stay vigilant to avoid
them. Examples of vital structures include the temporal nerve
in the upper part of the cheek and temple, the marginal
mandibular nerve on the jaw line, and CN XI at the Erb point.
• Identify sensory innervation to structures in the operative
field, and perform a nerve block wherever possible to
minimize the patient's discomfort and distortion of the
operative field by using large amounts of lidocaine.
• When working in deeper planes, attempt to identify the
SMAS, which can help in locating and avoiding vital vessels
and nerves.
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