Anatomy:
① External Nose — pyramidal structure
Formed by a bony part and a cartilaginous part
Bone Part 1/3ʳᵈ of nose
- Nasal Bones: These are paired bones that form the bridge of the nose, contributing to its overall structure and shape.
- Nasal process of frontal bone: articulates with the nasal bones and helps form the upper part of the nasal bridge
Innervation:
- Olfactory CN I
- Sensory innervation from terminal branches of the CN V1 & V2 Ophthalmic & Maxillary
- Motor- Mimetic muscles = CN V3
- Autonomic- Sympathetic / parasympathetic
- Masticatory muscles = mandibular nerve branch from the trigeminal nerve CN V3
Cartilaginous Part 2/3ʳᵈ of nose - contributing to its appearance and structure.
- Upper Lateral Cartilages
- Lower Lateral Cartilages
- Lateral Crus
- Medial Crus
- Septal Cartilage - single, flexible cartilage located in the center of the nose, forming the nasal septum and providing support to the nose structure. Deviation may Interfere w/ air flow → must be surgically corrected
- Columella - btw 2 nostrils – skin + cartilaginous
- Alar Cartilages
- Greater Alar Cartilages
- Lesser Alar Cartilages
- Nares: which are the external openings of the nasal cavity
Innervation:
- Olfactory CNI
- Sensory innervation from terminal branches of the CN V1 & V2 Ophthalmic & Maxillary
- Motor- Mimetic muscles = CN VII
- Autonomic- Symphatetic / parasymphatetic
- Masticatory muscles = mandibular nerve branch from the trigeminal nerve CN V3
Vascular supply:
External Nose:
- Facial artery (arising from external carotid a.)
- Ophthalmic artery (arising from internal carotid a.)
Internal Nose:
- Sphenopalatine artery (arising from external carotid a.)
- Anterior + Posterior ethmoid arteries (arising from internal carotid a.)
Venous supply:
- Facial vein, retromandibular vein, internal jugular vein
② Internal Nose – The nasal cavity
Roof is narrow, Base is wide
Air-conditioning chamber that houses the Septum and Turbinates (conchae) with rigid walls and floors that measures: Oval openings that open into nasopharynx
- irregular spaces between them which form the ”Flues” for the flow of air
- Superior wall / Roof - Ethmoid & Frontal bone
- Inferior wall / Floor - Hard palate - made from 2 palatine process of maxilla and horizontal laminae of palatine bone + Sinus ostia
- Lateral wall - Ethmoid, lacrimal, Inferior nasal concha & Maxilla bone. Turbinates (Nasal Conchae) Superior Middle Inferior
- Functional importance = Middle turbinate: Most of the drainage tracts from surrounding paranasal sinuses open into it
- Medial wall – Septum. (Septal cartilage & Process) Bones: Ethmoid & Vomer