Anatomy of Lateral wall of Nose

Anatomy of the Lateral Wall of Nose

The lateral wall of the nose is a critically important structure in ENT anatomy, often asked as a long question in theory exams.

It houses a complex arrangement of turbinates, meatuses, and sinus drainage pathways, which are essential to understand nasal physiology and various pathologies.

🌀 Overview

The lateral nasal wall includes:

• 3 (occasionally 4) turbinates: Inferior, Middle, Superior (± Supreme)

• 3 meatuses: Inferior, Middle, Superior (beneath corresponding turbinates)

📍 Inferior Turbinate and Meatus

• Inferior turbinate: A separate bone.

• Inferior meatus: Lies between inferior turbinate and lateral wall.

Which duct opens into the Inferior Meatus?

What is Hasner's Valve?

Why does the nose water during crying?

📍 Middle Turbinate and Meatus

• Part of ethmoid bone.

• Attached via the ground/basal lamella in an S-shaped course.

How is the basal lamella attached to the lateral nasal wall? Mention the planes and it's attachments.

What is pneumatisation of Middle turbinate called as?

🔄 Osteomeatal Complex (OMC)

A key area in middle meatus involved in drainage of:

• Frontal sinus
• Maxillary sinus
• Anterior ethmoidal air cells

Components of Osteomeatal Complex (OMC):

1- Uncinate process - anterior sickle-shaped bone

What is the attachment of Uncinate process?

How does variation in uncinate process attachment affects frontal sinus drainage?

What is the surgical importance of uncinate process?

2- Bulla ethmoidalis - Most consistent anterior ethmoidal air cell

What is Sinus Lateralis of Grunwald? What are it's boundaries?

3- Hiatus semilunaris inferior - space between 1 & 2

4- Ethmoidal infundibulum - 3D space leading to sinus ostia

What are the boundaries of Ethmoidal infundibulum?

📍 Frontal Recess

• Space draining frontal sinus via frontal ostium.

• Bordered by:

  • Anterior: Agger nasi cell
  • Posterior: Bulla ethmoidalis
  • Medial: Middle turbinate
  • Lateral: Lamina papyracea

What is Frontal Infundibulum?

Which structures form the hour glass configuration of Frontal Recess?

What is the surgical importance of Frontal Recess?

📍 Other Middle Meatus Features

• Agger nasi cell: Pneumatized ethmoidal cell anterior to middle turbinate.

What is the surgical importance of enlarged agger nasi cell?

• Atrium: Shallow depression in front of middle turbinate, above vestibule.

• Hiatus semilunaris superior: Connects sinus lateralis of Grunwald to middle meatus.

When is Hiatus semilunaris superioris absent?

📍 Superior Turbinate and Meatus

• Superior turbinate: Ethmoidal, lies above & posterior to middle turbinate.

  • Landmark for sphenoid sinus ostium.

• Superior meatus: Space below the Superior Turbinate.

Which sinus drains into Superior Meatus?

📍 Supreme Turbinate

• Supreme turbinate (occasional): May lie above superior turbinate with narrow meatus.

📍 Sphenoethmoidal Recess

• Located above superior turbinate.

• Sphenoid sinus opens into this space.

What is the location of the Sphenoid sinus ostium?

🩸 Blood Supply of the Lateral Wall

Internal Carotid System:

• Anterior & Posterior Ethmoidal arteries

External Carotid System:

• Sphenopalatine artery (posterolateral nasal branches)
• Greater palatine artery
• Facial artery (vestibule)
• Anterior superior dental artery (nasal branch)

What is Woodruff’s Plexus?

What is the most common site for posterior epistaxis in adults?

📝 Final Notes

The lateral nasal wall is not just an anatomical curiosity — it’s the hub of sinus drainage, airflow regulation, and common disease origins. Understanding its complex architecture is essential for mastering ENT.

📚 Commonly Tested Points:

• Osteomeatal complex components
• Sinus lateralis of Grunwald
• Frontal recess boundaries
• Uncinate process attachment variations
• Woodruff’s and Kiesselbach’s plexuses