2. Kiesselbach plexus

uncomplicated epistaxis (nosebleed) following facial trauma. The most common source of bleeding in patients with uncomplicated epistaxis is the Kiesselbach plexus–an area found in the anterior third of the nose. Anastomosis of the following blood vessels occurs in this region:
1. Septal branch of the anterior ethmoidal artery
(internal carotid--> ophthalmic-->ant.eth.art)
2. Lateral nasal branch of the sphenopalatine artery
(external carotid -> maxillary art. ->sphenopalatine art)
3. Septal branch of superior labial artery
( external carotid-> facial. art-> sup.lab.art)
Posterior epistaxis, on the other hand, occurs from bleeding in the Woodruff plexus–a collection of arteries in the posteroinferior nasal cavity formed by the anastomoses of the sphenopalatine artery (branch of the maxillary artery) and pharyngeal artery. Posterior epistaxis often presents as difficult to control bleeding from the bilateral nostrils or hemoptysis. Posterior epistaxis is highly associated with brisk bleeding into the posterior pharynx and thus a higher risk of airway compromise or aspiration.