Layers of Scalp Question And Answers

Platysma

• Platysma is one of the muscle of neck

Platysma Origin:

• Upper part of pectoral & deltoid fascia
• Fibres run upwards and medially

Platysma Insertion:

• Anterior fibres, to the base of the mandible
• Posterior fibres to the skin of the lower face and lip & may be continuous with the risorius

Platysma Action:

• Releases pressure of skin on the subjacent veins
• Depresses mandible
• Pulls the angle of the mouth downwards as in horror or surprise

Platysma Nerve Supply:

• Cervical branch of facial nerve

Platysma Examination:

• Forcible pulling of the angles of the mouth downwards & backward forming prominent vertical folds of skin on the side of neck

Facial expression associated with It:

• Horror, terror, fright

 

 Zygomatic major

Zygomatic major Origin:

• From the surface of the zygomatic bone lateral to zygomatic minor muscle

Facial expression associated with it: Smiling & laughing

Nerve Supply: Buccal branch of facial nerve

 Orbicularis oris

Orbicularis oris Parts:

1. Intrinsic part

• It is very thin sheet
  Origin:
• Superior incisivus from maxilla
• Inferior incisivus from mandible
  Insertion:
• Angle of mouth

2. Extrinsic part.

• It has two strata formed by converging muscles
  Origin:
• Thickest middle stratum from buccinators
• Thick superficial stratum from elevator & depressor of lip & their angles
  Insertion:
• Lips & the angle of the mouth
  Action:
• Closes & purses the mouth
  Nerve Supply:
• Temporal branch of facial nerve
  Examination:
• Whistling & pursing the mouth

 Orbicularis oculi

Orbicularis oculi Parts:

Orbicularis oculi Actions:

1. Orbital part

• It closes the eye tightly, wrinkling
• Protects eye from bright light

2. Palpebral part

• Closes the eye gently in sleep or in blinking

3. Lacrimal part

• Draws the lacrimal papillae medially
• Dilates lacrimal sac
• Supports lower lid

Orbicularis oculi Examination:

• Tight closure of the eyes

Orbicularis oculi Applied Anatomy:

• Paralysis of this muscle leads to
  1. Drooping of lower eyelid
  2. Spilling of tears

Sensory and motor nerve supply of scalp

1. Sensory nerve supply

• In front of auricle: branches are
  1. Supratrochlear nerve
     • It is branch of frontal nerve which in turn is branch of ophthalmic division of trigeminal nerve
  2. Supraorbital Nerve
     • Branch of frontal nerve which in turn is branch of ophthalmic division of trigeminal nerve
  3. Zygomaticotemporal nerve
     • Branch of zygomatic nerve which is branch of maxillary division of trigeminal nerve
  4. Auriculotemporal nerve
     • It is branch of mandibular division of trigeminal nerve
• Behind the auricle
  1. Posterior division of great auricular nerve
     • Branch from cervical plexus C2, C3
  2. Lesser occipital nerve
     • Branch from cervical plexus C2
  3. Greater occipital nerve
     • Branch from C2, dorsal ramus
  4. Third occipital nerve
     • Branch from C3, dorsal ramus

2. Motor nerves

1. In front of auricle
   1. Temporal nerve
      • Branch of facial nerve
2. Behind the auricle
   1. Posterior auricular
      • Branch of facial nerve

Thus Scalp has got its sensory nerve supply from branches of trigeminal nerve and cervical plexus while motor nerve supply is from facial nerve

Loose areolar tissue of scalp and its applied anatomy

4th layer of scalp is loose areolar tissue

• Loose areolar tissue contains emissary veins devoid of valves
• This communicates the veins of scalp with intracranial venous sinuses

Loose Areolar Tissue  Extent:

• Anteriorly eyelids
• Posteriorly Highest and superior nuchal lines
• Each side superior temporal lines

Loose Areolar Tissue Applied Anatomy:

• Loose Areolar Tissue is referred as dangerous area of scalp
• This is because of opening of emissary veins here
• If blood is collected in this layer, it may lead to generalised swelling

 Levator Palpebrae Superioris

• Levator Palpebrae Superioris is dilator of palpebral fissure
• Levator Palpebrae Superioris has radial arrangement
• They are better develop around the eyes

Levator Palpebrae Superioris Origin:

• Inferior surface of lesser wing of sphenoid
• Orbital surface of the body of sphenoid anterior to the optic foramen

Levator Palpebrae Superioris Insertion:

• Orbital septum and palpebral ligaments
• Superior tarsal plate
• Skin of upper eyelid

Levator Palpebrae Superioris Nerve supply:

• Upper division of oculomotor nerve
• Sympathetic chain from T₁ segment of the spinal cord

Levator Palpebrae Superioris Applied anatomy:

• Paralysis of this muscle causes drooping of upper eyelid called ptosis

 Layers of scalp with its applied aspects

Layers of scalp:

 Facial nerve in face

• The facial nerve leave the skull by passing through stylomastoid foramen
• Next it crosses the lateral side of the base of the styloid process
• Enters the posteromedial surface of the parotid gland
• Crosses the retromandibular vein and external carotid artery
• Behind the neck it divides into five terminal branches which emerges along the anterior border of the parotid gland

Facial nerve in face Branches:

• Within the facial canal
  • Greater petrosal nerve
  • Nerve to the stapedius
  • Chorda tympani nerve
• At its exit from stylomastoid foramen
  • Posterior auricular
  • Digastric
  • Stylohyoid
• Terminal branches
  • Temporal
  • Zygomatic
  • Buccal
  • Marginal mandibular
  • Cervical
• Communicating branches with adjacent cranial and spinal nerves

 Retromandibular vein

Retromandibular vein Formation:

• Retromandibular vein is formed by the union of the superfical temporal and maxillary vein

Retromandibular vein Course:

• Descends in substance of parotid gland superficial to external carotid artery
• Runs between ramus of mandible and sternocleidomastoid muscle

Retromandibular vein Branches:

1. Anterior branch
   • Joins anterior facial vein to form common facial vein
   • Drains into internal jugular vein
2. Osterior branch
   • Joins posterior auricular vein to form external jugular vein

Retromandibular vein Applied Anatomy:

• Parrot’s sign
  • Retromandibular vein  is sensation of pain when pressure is applied to the retromandibualr vein

 Venous drainage of face

Venous Drainage:

Veins of the face communicates with the cavernous sinus.

 Occipitofrontalis muscle

Occipitofrontalis muscles have two bellies

1. Occipital or occipitalis
2. Frontal or frontalis

Actions:

• Raises the eyebrows
• Causes horizontal wrinkles in the skin of the forehead.

Question 20. Bell’s palsy
Answer:

Idiopathic paralysis of the facial nerve of sudden onset

Etiology 5 HYPOTHESIS:

• Rheumatic
• Cold
• Ischaemia
• Immunological
• Viral

Bell’s palsy Clinical Features:

• Pain in post auricular region
• Sudden onset
• Unilateral loss of function
• Loss of facial expression
• Absence of wrinkles on forehead
• Loss of wrinkles
• Crocodile tears
• Inability to close the eyean effort to do so causes roung or eyeball upwards
• Watering of eye
• Inability to blow the cheek
• Nasolabial fold disappears
• Tip of nose is deviated

• Loss of taste sensation
• Hyperacusis
• Slurring of speech

Deep facial vein

• Deep connection of facial vein include a communication between supraorbital & pterygoid plexus through deep facial vein, which passes backward over buccinators
• The facial vein communicates with cavernous sinus through these connections

Deep facial vein Applied Anatomy:

• Infections from the face specially from upper lip & in the lower part of face can spread in retrograde direction & cause thrombosis of cavernous sinus
• This area is, therefore, called dangerous area of the face

 Secretomotor supply to lacrimal gland.

 Palpebral ligament

• The palpebral fascia of the two lids forms the orbital septum
• Its thickening from tarsal plates of tarsi in the lids & palpebral ligaments at the angles

 Dangerous area of scalp.

Loose areolar tissue

• Loose areolar tissue is fourth layer of scalp
• Loose areolar tissue is known as “Dangerous area of scalp” as emissary vein open here
• If blood is collected in this layer, it leads to generalized swelling

Question 25. Palatine aponeurosis
Answer:

The posterior border of the hard palate provides attachment to the palatine aponeurosis

Levator palpebrae superioris

• Levator palpebrae superioris is dilator of palpebral fissure
• Levator palpebrae superioris has radial arrangement
• They are better develop around the eyes

Levator palpebrae superioris Origin:

• Inferior surface of the lesser wing of sphenoid
• Orbital surface of the body of the sphenoid anterior to the optic foramen

Levator palpebrae superioris Insertion:

• Orbital septum & palpebral ligaments
• Superior tarsal plate
• Skin of the upper eyelid

Levator palpebrae superioris Nerve Supply:

• Upper division of the oculomotor nerve
• Sympathetic chain from T₁ segment of the spinal cord

Levator palpebrae superioris Applied Anatomy:

• Paralysis of this muscle causes drooping of the upper eyelid called ptosis

 

cervical branches of facial artery

• Ascending palatine nerve
• Tonsillar nerve
• Glandular nerve Submental nerve

formation & termination of anterior facial vein

• Supratrochlear & supraorbital veins unite at medial angle of eye
• It forms angular vein
• This continues and forms facial vein
• Then, facial vein alongwith anterior division of retromandibular vein forms common facial vein
• This drains & terminates as internal jugular vein

 Facial vein

• Facial vein is largest vein of the face with no valves

Facial vein Origin:

• At medial angle of eye as angular vein

Facial vein Course:

• Angular vein is formed by union of supraorbital & suprattrochlear vein
• Facial vein runs downward & backward behind facial artery
• Facial vein crosses anteroinferior angle of masseter, pierces deep fascia, crosses submandibular gland
• Facial vein joins anterior division of retromandibular vein below the angle of mandible to form common facial vein

Facial vein Terminates:

• Facial vein drains into internal jugular vein.

Branches of facial artery in face

1. Anterior branches

2. Posterior branches

• They are small and unnamed

 Branches of facial artery in neck

 Retromandibular vein

Retromandibular vein  Formation:

• Retromandibular vein is formed by the union of the superfieal temporal and maxillary vein

Retromandibular vein  Course:

• Descends substance of parotid gland superficial to external carotid artery
• Runs between ramus of mandible and sternocleidomastoid muscle

Retromandibular vein  Branches:

1. Anterior branch
   • Joins anterior facial vein to form common facial vein
   • Drains into internal jugular vein
2. Posterior branch
   • Joins posterior auricular vein to form external jugular vein

Nasolacrimal duct

• Nasolacrimal duct is 18 mm long membranous passage
• Valve of Hasner, a fold of mucous membrane forming imperfect valve is present at the lower end of nasolacrimal duct

Nasolacrimal duct Course:

• Begins at lower end of lacrimal sac
• Runs downwards, backwards and laterally
• Opens into inferior meatus of nose

Applied anatomy:

Epiphora a condition where there is excessive secretion of lacrimal fluid overflowing on the cheeks may occur due to the obstruction in the lacrimal fluid pathway at the level of nasolacrimal duct

Galea aponeurotica

• Galea aponeurotica is third layer of scalp
• Galea aponeurotica is freely movable

Galea aponeurotica Attachments:

• Anteriorlyinsertion of frontalis
• Posteriorlyinsertion of occipitalis
• In between occipital belliesexternal occipital protuberance and highest nuchal lines
• Each sideattached to superior temporal line

Galea aponeurotica  Applied anatomy:

• Wounds of the scalp donot gape unless this layer is divided transversely

 structures constituting lacrimal apparatus

1. Lacrimal gland and its dud
2. Conjunctival sac
3. Lacrimal puncta and canaliculi
4. Lacrimal snc
5. Nasolacrimal duct

Dangerous area of face

• The facial vein communicates with the cavernous sinus through its deep connections
• The facial vein is devoid of valves and rests directly on the facial muscles
• The movements of facial muscles facilitates the spread of emboli from the infected area of upper lip and lower part of the nose in retrograde direction and causes thrombosis of cavernous sinus
• Hence the area between the upper lip and lower part of nose is consider as dangerous area of face

Nerve supply of scalp

Name any six muscles of facial expressions.

cutaneous innervation of anterior quadrant of scalp.

Lacrimal gland

• Lacrimal gland is serous J shaped structure

Lacrimal gland Site:

• In the lacrimal fossa on the anterolateral part of the roof of the bony orbit and partly on the upper eyelid.

Lacrimal gland Parts:

• Orbital part larger and deeper
• Palpebral part smaller and superficial