anatomy of scalp layers of scalp, arterial & nerve supply. clinical application. temporal fossa To watch full video please click the link. https://youtu.be/1b40B8sgrho

1. 1
Supraorbital
margins
Zygomatic
arch
 The soft tissues covering the cranial vault from the scalp
 It is hair bearing area of the skull. The forehead, though not covered with
hair, is included in the scalp.
Anterior Supraorbital margins
Posterior External occipital protuberance
Laterally on each
side
Superior temporal lines and Zygomatic arch
Superior temporal
External occipital
protuberance
SCALP
Extent of scalp

2. 2
S - Skin
C - Connective tissue (superficial fascia)
A - Aponeurosis
L - Loose Areolar Connective Tissue (subaponeurotic layer)
P - Pericranium
Skin  The skin of scalp is characterized by plenty of hair
follicles, sebaceous glands and sweat glands.
 Firmly attached to the epicranial aponeurosis through
dense fascia
 Abundance sebaceous glands Sebaceous cyst are
common
Connective
tissue
 Binds skin to subjacent aponeurosis
 The superficial fascia is characterized by dense
connective tissue. It contains the blood vessels and
nerves of the scalp. The fibrous strands in the superficial
fascia are fixed to the walls of the blood vessels. This
The musculoaponeurotic layer consists of two parts:
i. Epicranial aponeurosis (galea aponeurotica)
ii. ii. Muscular part composed of frontal and
occipital bellies of the occipitofrontalis
muscle.
Structure

3. 3
factor prevents retraction of the blood vessels, when
injured. Hence, scalp wounds bleed profusely. The
bleeding in the scalp is controlled by application of direct
pressure of the digit or by placing the surgical sutures.
 Inflammation cause little swelling but are much painful
Aponuerosis
and muscle
 The galea aponeurotica covers the vault like a helmet.
 EPICRANIAL APONUEROSIS It is freely movable on the
pericranium along with the overlying and adherent scalp
and fascia.
 On each side it is attached to the superior temporal lines.
Anteriorly ,it receives the insertion of the frontalis.
Posteriorly ,receives insertion of the occipital bellies and
attached to the external occipital protuberance.
OCCIPITOFRONTALIS
LOOSE
AEREOLAR
TISSUE
 The subaponeurotic layer (fourth layer) forms a potential
space filled with loose areolar tissue beneath the
aponeurotic layer.
 The emissary veins, which communicate the veins of the
scalp with the intracranial venous sinuses, pass through
this space. This space is closed on all sides except
anteriorly, where it extends into the upper eyelid It is
known as the dangerous area of scalp.
 It Extends anteriorly into the eyelids.
 Posteriorly to the highest and superior nuchal lines and
on each side to the superior temporal lines.
PERICRANIUM  Loosely attached to the surface of the bones,but is firmly
adherent to the sutures where the sutural ligaments bind
the pericranium to the endocranium.

4. 4

5. 5
 Arteries supplying the scalp are branches of either the external carotid
artery or the ophthalmic artery which is a branch of the internal carotid
artery.
 External carotid arteries
o Occipital arteries
o Posterior auricular arteries
o Superficial temporal arteries
 Internal carotid arteries
o Supratrochlear arteries
o Supraorbital arteries
1. The following arteries supply the anterior quadrant:
i. Supratrochlear
ii. Supraorbital
The above two arteries are the branches of the ophthalmic artery
(a branch of internal carotid artery).
iii. Superficial temporal artery is the terminal branch of external carotid
artery.
2. The following arteries supply the posterior quadrant of scalp
i. Posterior auricular
ii. Occipital artery
The above two arteries are branches of external carotid artery.
Arterial Supply of the Scalp

6. 6
 Veins draining the scalp follow a pattern similar to the arteries.
a. The supratrochlear and the supraorbital vein unite at the medial angle
of eye to form angular vein.
b. The superficial temporal vein joins the maxillary vein to form
retromandibular vein.
c. The posterior division of retromandibular vein unites with the posterior
auricular vein to form external jugular vein.
d. The occipital vein drains into the suboccipital venous plexus. Which lies
beneath the floor of the upper part of the posterior triangle, the plexus in
turn drains into the vertebral veins or internal jugular vein.
 Of the deep parts of the scalp
o Via emissary veins that communicates with the dural sinuses
o Emissary vein connect the extracranial veins with the intracranial venous
sinuses to equalize the pressure, the veins are valveless.
o Parietal emissary vein, which passes through parietal foramen and
communicates with the superior sagittal sinus.
o Mastoid emissary vein, which passes through mastoid foramen and
communicates with the sigmoid sinus.
Venous Drainage of the Scalp

7. 7
 The lymphatics in the occipital region initially drain to occipital nodes which
drain into upper deep cervical nodes.
 lymphatics from the upper part of the scalp drain in two directions
o Posterior to the vertex of the head they drain to mastoid nodes.
o Anterior to the vertex of the head they drain to pre-auricular and
parotid nodes.
Lymphatic Drainage

8. 8
 Two main sources
o Cranial nerves :- (anterior to ear & vertex) by trigeminal nerves
o Cervical nerves:- (posterior to ear and vertex) by C2 &C3 nerves
Anterior to the ears and the
vertex
Posterior to the ears and the vertex
Sensory nerves
 Supratrochlear nerve
 Supraorbital nerve
 Zygomaticotemporal
nerve
 Auriculotemporal nerve
By branches of all four
divisions of the trigeminal
nerve
Sensory nerves
 Great auricular nerve
 Lesser occipital nerve
 Greater occipital nerve
 Third occipital nerve
By branches of all four divisions of the
spinal cutaneous nerves (C2 and C3)
Motor nerves
 Temporal branch of
facial nerve
Motor nerves
 Posterior auricular branch of
facial nerve
Nerve Supply

9. 9
 Skin of the scalp is the commonest site in the body for sebaceous cysts as it
is rich in sebaceous glands being the hairiest
 Cutaneous tissue of the second layer is divided into a number of loculi
containing fat in which infection sends to become localised and causes
severe pain.
 Wounds into the highly vascular second layer tend to bleed freely as the
walls of the blood vessels are attached to the fibrous septa so that they
cannot contract and retract to stop the haemorrhage
 A wound which cuts through the third layer gapes but the edges of a
wound which does not penetrate the aponeurosis remain together This is
because the aponeurosis is under tension because of its muscular
component and retracts only when divided
 The emissary veins which traverse the fourth layer I.e. the subaponeurotic
space connect the veins of the second layer with the intracranial venous
sinuses. A superficial infection of the scalp can spread via this system to
produce venous sinus thrombosis or meningitis
 The subaponeurontic space affords an easy plane of cleavage Blood or pus
collecting in this layer tracks freely under the first three layers but cannot
pass into either the superficial temporal region or the occipital region
because of the attachment of the occipitofrontalis muscle. Blood can,
however, spread into the upper eyelid causing a 'black eye that may form a
few hours after a severe head injury. This layer is known as the 'dangerous
layer as infection tends to spread readily within it.
 The pericranium is easily stripped up by collection of pus or blood beneath
it. The affected bone in outlined as the sutural membrane limits the spread
of collected fluid. This is particularly well seen in birth injuries involving the
skull and causing a cephalhematoma.
 Caput succedaneum is the formation of swelling in the newborn skull due to
stagnation of fluid in the scalp layers. This is a temporary swelling since it
Clinical Application

10. 10
results from the venous congestion of the scalp due to compression through
the birth canal. The swelling of caput succedaneum is diffuse because it is
not restricted to any particular bone. It disappears within 24 hours after
delivery.
 In newborn babies, there is slow accumulation of blood in this space, when
there is intracranial hemorrhage due to fracture of the bone of vault and
associated dural tear. The leakage of blood outside the cranium in the
potentially large subaponeurotic space delays the symptoms of cerebral
compression. Hence, the slow accumulation of blood in the fourth layer is
known as Safety valve hematoma.

11. 11
 The temple is the area between the temporal lines and the zygomatic arch
which must be studied in the view of the skull or norma lateralis .
 The temporal fossa is a shallow depression bounded above by the superior
temporal line on the frontal and parietal bones and below by the
zygomatic arch.
 The bones taking part in the formation of the fossa are the squamous part
of temporal (T), the greater wing of the sphenoid (S) and lower part of the
frontal (F) and perietal (P) bones. These bones articulate at an H-shaped
suture called the pterion
 The superior and inferior temporal lines are the duplication of the temporal
line on the parietal bone. The superior temporal line marks the upper limit
of the norma lateralis.
Lower part of the
Frontal
Greater Wing of the
Sphenoid
Squamous part of
temporal
Lower part of the
perietal
TEMPORAL FOSSA

12. 12
Bounded by
It contents consist of:

13. 13
There are six layers in this region.
 The first and second layers are the same as in the scalp I,e. skin and
cutaneous tissue
 The third layer is a thin expansion of the epicranial aponeurosis of
the scalp from which the auricularis anterior and superior muscles
arise
 The fourth layer is the temporal fascia (Fig 2.7) which is attached
above to the superior temporal line and below to the zygomatic arch
It is a rugged membrane. The superior temporal vessels and the
auriculotemporal nerve lie upon it, and it is perforated by the middle
temporal artery and vein .
 The fifth layer is the temporalis muscle . which arises from the whole
of temporal fossa. The large fan- shaped muscle converges towards
the coronoid process mandible .
Layers in temporal region

14. 14
 The sixth or the last layer is the same as in the scalp i.e. pericranium.
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