What are the blood supplies and anatomical borders of the nasal septum?

Blood Supply and Anatomical Borders of the Nasal Septum

The nasal septum receives blood supply from multiple arteries including the anterior ethmoidal artery, posterior ethmoidal artery, sphenopalatine artery, greater palatine artery, and superior labial artery, which form an anastomotic network at Kiesselbach's plexus. 1

Blood Supply of the Nasal Septum

Arterial Supply

1. Anterior Ethmoidal Artery

   • Branch of the ophthalmic artery
   • Supplies the anterosuperior portion of the septum
   • Contributes to Kiesselbach's plexus 1, 2

2. Posterior Ethmoidal Artery

   • Branch of the ophthalmic artery
   • Supplies the superior portion of the septum 1

3. Sphenopalatine Artery

   • Terminal branch of the maxillary artery
   • Enters the nasal cavity through the sphenopalatine foramen
   • Divides into posterior septal branches on the sphenoid rostrum 3
   • Bifurcates in most cases (observed in 7/7 cadaveric dissections) 3
   • Supplies the posterior and inferior portions of the septum 1, 4

4. Greater Palatine Artery

   • Branch of the maxillary artery
   • Supplies the inferior portion of the septum 1, 2

5. Superior Labial Artery

   • Branch of the facial artery
   • Supplies the anteroinferior portion of the septum
   • Contributes to Kiesselbach's plexus 1, 2

Kiesselbach's Plexus (Little's Area)

• Located on the anterior nasal septum
• Forms an anastomotic triangle receiving contributions from:
  • Sphenopalatine artery
  • Anterior ethmoidal artery
  • Superior labial artery 2
• This is not a random network but a consistent arterial anastomotic triangle consisting of large, thin vessels 2
• Common site of epistaxis (nosebleeds) 1

Anatomical Borders of the Nasal Septum

Superior Border

• Formed by the nasal bones and the perpendicular plate of the ethmoid bone
• Connects to the cribriform plate of the ethmoid bone 1

Inferior Border

• Formed by the maxillary crest and the palatine bone
• Connects to the nasal floor 1

Anterior Border

• Formed by the columella externally
• Connects to the nasal spine of the maxilla 5

Posterior Border

• Formed by the vomer bone
• Connects to the sphenoid rostrum 4

Lateral Borders

• Connect to the lateral nasal walls
• Form the internal nasal valve (the narrowest portion of the anterior nose)
• Responsible for more than 2/3 of airflow resistance produced by the nose 1

Clinical Significance

The vascular anatomy of the nasal septum is clinically significant for several reasons:

1. Epistaxis Management

   • Most nosebleeds originate from the nasal septum, particularly Kiesselbach's plexus 1
   • Understanding the vascular supply is crucial for effective treatment of epistaxis 6

2. Surgical Considerations

   • Important for septoplasty and other nasal surgeries 1, 5
   • The septal valve (space between anterior tip of inferior turbinate and septum) is the area most commonly associated with subjective perception of obstruction 1
   • Septal deviation occurs in approximately 80% of the general population, with clinically significant deviation in 26% of patients with nasal obstruction 1

3. Endoscopic Approaches

   • Knowledge of the arterial anatomy is crucial for endoscopic procedures and flap development 3, 7
   • The sphenopalatine foramen serves as an important landmark, located at the transition between superior and middle nasal meatus in 95% of cases 4

Understanding this complex vascular network is essential for clinicians managing epistaxis, performing nasal surgeries, or developing endoscopic approaches to the nasal cavity.