What is the primary blood supply to the nasal septum?

Blood Supply of the Nasal Septum

Primary Arterial Supply

The nasal septum receives its blood supply from four main arteries that converge to form Kiesselbach's plexus (Little's area) in the anterior septum: the sphenopalatine artery (posterior septal branch), anterior ethmoidal artery, superior labial artery, and greater palatine artery. 1

Anatomical Organization

Anterior Septum - Kiesselbach's Plexus

• Kiesselbach's plexus is located in the anteroinferior nasal septum and represents the convergence point of multiple arterial sources 1
• This plexus receives contributions from:
  • Sphenopalatine artery (posterior septal branch) - the dominant contributor 1, 2, 3
  • Anterior ethmoidal artery (septal branch) 1, 2, 3
  • Superior labial artery (septal branch) 1, 2, 3
  • Greater palatine artery (ascending septal branch) 1, 3

Posterior Septum

• The posterior septal artery (terminal branch of the sphenopalatine artery) supplies the posterior nasal septum 3, 4
• This artery exits through the sphenopalatine foramen and typically bifurcates on the sphenoid rostrum into superior and inferior branches, with the inferior branch being dominant in 61.5% of cases 3, 4

Superior Septum - S-Point Area

• The S-point (corresponding to the medial projection of the middle turbinate axilla) is surrounded by arterial anastomotic arches formed by branches of the anterior and posterior ethmoidal arteries superiorly and the posterior septal artery inferiorly 5
• These anastomotic arches have larger caliber vessels than their feeding branches, explaining why this area is a frequent source of severe epistaxis 5

Arterial Anastomotic Triangle

Microdissection studies demonstrate that the anterior septum contains a consistent large arterial anastomotic triangle rather than a random vascular network, with major contributions from the sphenopalatine, anterior ethmoidal, and superior labial arteries forming large, thin-walled vessels 2

Clinical Significance

• The majority of nosebleeds (>90%) originate from the anterior nasal septum, specifically from Kiesselbach's plexus, due to the superficial location and convergence of multiple arterial sources 1, 6
• Posterior epistaxis accounts for only 5-10% of nosebleeds but is more difficult to control and occurs more commonly in elderly patients 1
• Understanding this vascular anatomy is essential for surgical arterial ligation procedures, as failure to identify and ligate the sphenopalatine artery specifically will leave an important component of posterior nasal circulation unaddressed 7