GROSS ANATOMY OF RESPIRATORY SYSTEM

ANATOMY MRES
L1: GROSS ANATOMY OF THE NOSE, NASAL CAVITY AND
PARANASAL AIR SINUSES
The nose is categorized into external nose and nasal cavity.
The external nose have two parts :
I. Bony part - nasal bone, frontal process of maxilla & nasal part of
frontal bone
II. Cartilaginous part - septal, alar, lateral nasal cartilage, fibro fatty
tissue
Boundaries of nasal cavity :
- Extend from naris to choanae
- Space inside the nose separated by nasal septum
I. Floor - hard palate
II. Roof - sphenoid and ethmoid bone
III. Medial wall - septum
IV. Lateral wall – medial orbit, ethmoidal air cells, maxillary sinus
Subdivision of mucosal membrane of nasal cavity
I. Vestibule – dilated area inside naris bounded by alar cartilages & the
skin, limited above by curved limen nasi and agger nasi




II. Respiratory region – inferior 2/3rds of nasal, lined by pseudostratified
ciliated columnar epithelium with goblet cells
III. Olfactory region – superior 1/3rd of nasal mucosa above superior
conchae, lined by bipolar olfactory cell - olfactory epithelium have
bipolar neurons


Functions of the nose and nasal cavity
I. Smell – felt at the roof of the nasal cavity ( olfactory nerve )
II. Respiration
III. Filters foreign particles by the coarse hairs to protect air passages

, - Muco-ciliary barrier moves the trapped particles into the nasopharynx
and excreted out by sneezing or coughing.
Lateral wall of nasal cavity Bone forming – nasal bone, lacrimal
bone, perpendicular plate of palatine
bone, medial plate of sphenoid bone
Arterial & Nerve supply
 Anterior ethmoidal atery & nerve
( ASP )
 Terminal branches of greater
palatine artery & Anterior superior
alveolar nerve, infraorbital nerve
( AIP )
 Posterior ethmoidal artery &
Posterior superior lateral nasal
branches ( PSP )
 Branches of sphenopalatine artery

3 bony ridges
i. Superior concha – extend from ethmoid bone
ii. Middle concha – extend from ethmoid bone
iii. Inferior concha – separate bone

 These conchae covered by mucous membrane – increase
S.A for respiratory
 There are meatus ( bony opening ) below each concha –
humidification, filtering the inhaled air


NASAL PASSAGE OPENING
INFERIOR MEATUS NASOLACRIMAL DUCT
MIDDLE MEATUS FRONTAL SINUS
MAXILLARY SINUS
ANTERIOR ETHMOIDAL SINUS
MIDDLE ETHMOIDAL SINUS
SUPERIOR MEATUS POSTERIOR ETHMOIDAL SINUS
SPHENOETHMOIDAL SPHENOID SINUS
RECESS


Lymphatic drainage

, i. Anterior half of lateral wall – SUBMANDIBULAR LYMPH NODE
ii. Posterior half of lateral wall – DEEP CERVICAL LYMPH NODE




FLOOR OF NASAL CAVITY
1. Hard Palate – The palatine process of maxilla & Horizontal plate of
palatine bone
2. Soft Palate – Roof of the oral cavity, separates both cavities
ROOF OF NASAL CAVITY


-

 Nasal and frontal bone
 Cribiform plate of ethmoid
 Sphenoid body
- Lined by olfactory epithelium ( sense
of smell )