INTRODUCTION AND SCALP

INTRODUCTION AND SCALP

Main areas of the head and neck region

• Cranium: The upper part of the skull that encloses the brain
• Face: The front part of the skull that includes the maxilla, zygoma, and mandible
• Neck: The region below the skull that connects the head to the rest of the body
• Scalp: The outermost layer of the head that covers the cranium
• Face and neck muscles: Various muscles that control facial expressions, mastication, and neck movements

Layers of the scalp

1. Skin
2. Connective tissue
3. Aponeurosis (galea aponeurotica)
4. Loose connective tissue
5. Periosteum

Blood supply to the scalp

• Arterial supply:
  • Supratrochlear artery (branch of the ophthalmic artery)
  • Supraorbital artery (branch of the ophthalmic artery)
  • Occipital artery
  • Posterior auricular artery
  • Anterior auricular artery
  • Frontal branches of the superficial temporal artery
• Venous drainage:
  • Supratrochlear vein
  • Supraorbital vein
  • Occipital veins
  • Posterior auricular vein
  • Anterior auricular veins

Nerve supply to the scalp

• Sensory innervation:
  • Supraorbital nerve (V1)
  • Supratrochlear nerve (V1)
  • Auriculotemporal nerve (V3)
  • Greater occipital nerve (C2)
• Motor innervation:
  • Frontalis muscle
  • Occipitalis muscle
  • Auricular muscles

Applied anatomy of the scalp

• Scalp is a common site for surgical procedures
• Scalp flaps are used in reconstructive surgery
• Scalp incisions should be made at least 1.5 cm away from the midline to avoid the sagittal sinus
• Scalp lacerations can be a source of infection

Diagram: Layers of the scalp

+---------------------------------------+ | Skin | +---------------------------------------+ | Connective tissue | +---------------------------------------+ | Aponeurosis (galea | | aponeurotica) | +---------------------------------------+ | Loose connective tissue | +---------------------------------------+ | Periosteum | +---------------------------------------+

Flowchart: Blood supply to the scalp

Arterial supply → → Supratrochlear artery (ophthalmic artery) → Supraorbital artery (ophthalmic artery) → Occipital artery → Posterior auricular artery → Anterior auricular artery → Frontal branches of the superficial temporal artery