Lateral nasal wall

LATERAL NASAL WALL    

• Has 3 bony projections called as turbinates or conchae.
• Irregular due to pressence of 3 conchae.
• Seperates the nose from:

1. Above orbit
2. Below maxillary sinus
3. Front Lacrimal groove & naolacrimal canal

Subdivided into:

1. Vestibule small depressed area in ant. 
2. Atrium of middle meatus in middle
3. Posterior contains conchae

Bony part:

1. Nasal
2. Frontal process of maxilla
3. Lacrimal
4. Labryinth of ethmoid with superior & middle conchhae
5. Inferior conchae
6. Palatine bone (perpendicular plate, Orbital & sphenoidal process)
7. Medial pterygoid Plate

Cartilagenous part:

1. Superior nasal 
2. Inferior nasal
3. 3 to 4 from ala

CONCHAE/ TURBINATES:

• Curved paired bony projection directed downward & medially:

1. Inferior conchae (Largest): Independant bone.
2. Middle conchae:  projects from medial surface of ethmoidal labyrinth
3. Superior conchae (smallest): projects from medial surface of ethmoidal labyrinth.

→ The inferior turbinate is a separate bone, while rest of the turbinates are a part of ethmoidal bone.

→ Sometimes fourth turbinate is also present just above superior turbinate known as Supreme turbinate.

→ The middle , superior & supreme turbinates are part of erhmoidal complex, they may be called as “ethmoidal turbinates”. 

 → Atrium is a shallow depression in front of the middle turbinate.

MEATUS:

• Passage beneath overlying conchae
• Communicates with nasal cavity proper

1. Inferior meatus (largest): Under inferior conchae

• Give opening to nasolacrimal duct (at junction of ant.1/3 & post. 2/3) guarded by Hasner’s valve or lacrimal fold.

2. Middle meatus: Under middle conchae.

Structures present in it: 

1. Ethmoidal bulla: round elevation produced by underlying ethmoidal sinus. Gives opening to middle ethmoidal air sinus.
2. Hiatus semilunaris: semicircular sulcus below bulla. Gives opening to:

• Ant.: frontal air sinus
• Post. maxillary sinus(2 openings)
• Anterior ethmoidal sinus

1. Infundibulum: Passage at ant. end of hiatus
2. Uncinate process of ethmoid: It partly covers the opening of maxillary sinus.

3. Superior meatus (shortest & shallowest): under superior conchae.                                                         

• Recives opening of posterior ethmoidal air sinus.

4. Sphenoethmoidal Recess:

• Triangular Fossa above superior conchae that recieves opening of sphenoidal air sinus.

BLOOD SUPPLY:

ARTERIAL SUPPLY:

• Anterosuperior: Anterior ethmoidal , posterior ethmoidal & facial arteries
• Anteroinferior: Facial & greater palatine
• Posterosuperior: Sphenopalatine
• Posteroinferior: Greater palatine

VENOUS DRAINAGE:

• Forms a venous plexus that drains
• Ant. Facial vein
• Post. Pharyngeal plexus of vein
• Middle: Pterygoid plexus of vein

NERVE SUPPLY:

  1. General sensory:

1. Anterosuperior: Anterior ethmoidal of opthalmic nerve
2. Anteroinferior:  Anterior superior alveolar of maxillary nerve
3. Posterosuperior: Posterior superior lateral nasal from pterygopalatine gangalion
4. Posteroinferior:Ant. or greater palatine from pterygopalatine ganglion

  2. Special sensory:

• Olfactory from upper part below cribriform plate of ethmoid to superior concha

LYMPHATIC DRAINAGE:

• Anterior half: Submandibular nodes
• Posterior half: Retropharyngeal & upper deep cervical nodes

Exam Question

LATERAL NASAL WALL 

CONCHAE/ TURBINATES:

•  Curved paired bony projection directed downward & medially:

1. Inferior conchae (Largest): Independant bone.
2. Middle conchae:  projects from medial surface of ethmoidal labyrinth
3. Superior conchae (smallest): projects from medial surface of ethmoidal labyrinth.

→ The inferior turbinate is a separate bone, while rest of the turbinates are a part of ethmoidal bone.

→ Sometimes fourth turbinate is also present just above superior turbinate known as Supreme turbinate.

→ The middle , superior & supreme turbinates are part of erhmoidal complex, they may be called as “ethmoidal turbinates”. 

MEATUS:

• Passage beneath overlying conchae
• Communicates with nasal cavity proper

1. Inferior meatus (largest): Under inferior conchae

• Give opening to nasolacrimal duct (at junction of ant.1/3 & post. 2/3) guarded by Hasner’s valve or lacrimal fold.

2. Middle meatus: Under middle conchae.

Structures present in it: 

1. Ethmoidal bulla: round elevation produced by underlying ethmoidal sinus. Gives opening to middle ethmoidal air sinus.
2. Hiatus semilunaris: semicircular sulcus below bulla. Gives opening to:

• Ant.: frontal air sinus
• Post. maxillary sinus(2 openings)
• Anterior ethmoidal sinus 

1. Infundibulum: Passage at ant. end of hiatus
2. Uncinate process of ethmoid: It partly covers the opening of maxillary sinus.

 → Atrium is a shallow depression in front of the middle turbinate.

3. Superior meatus (shortest & shallowest): under superior conchae.

•  Recives opening of posterior ethmoidal air sinus. 

4. Sphenoethmoidal Recess:

• Triangular Fossa above superior conchae that recieves opening of sphenoidal air sinus.