Epistaxis is one of the most common otolaryngologic emergencies.

Minor epistaxis usually originates from the anterior nasal septum and is often satisfactorily treated with direct pressure or anterior nasal packing.

Epistaxis that is not controlled by adequate anterior nasal packing can be pragmatically defined as posterior epistaxis. Refractory posterior epistaxis is continued hemorrhage that occurs despite placement of anteroposterior nasal packing or shortly after its removal.

Traditionally, the initial management of posterior epistaxis involved placement of anteroposterior nasal packing and inpatient observation. This procedure, however, is associated with significant morbidity. This has led to earlier intervention with a variety of means, including transarterial embolization, internal maxillary artery ligation, anterior ethmoid artery ligation, and endoscopic sphenopalatine artery (SPA) ligation.

Embolization is a nonsurgical option to controlling epistaxis. It may not be available in many institutions and is typically more costly than endoscopic surgical control.

Transantral internal maxillary artery ligation through a Caldwell-Luc antrostomy is relatively straightforward but is now rarely performed since there is decreased morbidity and increased effectiveness with surgical ligation of the SPA and the anterior ethmoid artery.

Anterior ethmoid artery ligation via an external (or even an endoscopic) approach can be performed as an adjunct to SPA ligation. Vascular supply to the nasal mucosa from this branch of the internal carotid artery is usually of secondary importance.

Endoscopic SPA ligation was first described in 1992. As rigid endoscopes have become increasingly available, this technique has been refined to require minimal dissection. Because the endoscopic technique provides excellent visualization and is associated with low morbidity, it is now the first-line surgical treatment for refractory posterior epistaxis.

SPA ligation is not intended for the treatment of epistaxis associated with the use of anticoagulants and antiplatelet drugs. Patients with this type of epistaxis are better treated with limited cauterization and placement of resorbable hemostatic packing materials.

SPA ligation is also unlikely to provide long-term improvement in epistaxis associated with hereditary hemorrhagic telangiectasia.

The lateral nasal wall is supplied by the SPA as well as the anterior and posterior ethmoid arteries ( Fig. 3.1A and Fig. 3.1B ).

(A) Drawing of the vascular supply of the nasal septum. Note that the sagittal cuts are as if the patient’s right nose had been opened like a book. The anterior and posterior ethmoid arteries arise from the ophthalmic artery and perfuse the superior septum and lateral nasal wall. The sphenopalatine artery, which comes off the internal maxillary artery, perfuses most of the lateral nasal wall and septal mucosa. The septal branch of the sphenopalatine artery crosses from the lateral nasal wall to the septum just under the sphenoid sinus ostium. (B) Drawing showing three-quarter view of the blood supply of the nose. The contents of the orbit are treated as if transparent. The ophthalmic artery enters through the optic canal and sends branches of the posterior and anterior ethmoid arteries to supply the superior portions of the nasal cavity. a., Artery.

The SPA, a terminal branch of the internal maxillary artery (IMA) from the external carotid artery, supplies blood to up to 90% of the nasal mucosa.

The anterior and posterior ethmoid arteries, branches of the ophthalmic artery from the internal carotid artery, also contribute significantly to nasal blood flow.

The anterior ethmoid artery is larger than the posterior ethmoid artery and is more clinically significant. It is the major blood supply to the anterior third of both the septum and lateral nasal wall.

The posterior ethmoid artery supplies a small area on the superior concha and adjacent septum.

The labial artery, a branch of the facial artery, also supplies the nasal vestibule. In addition, branches of the greater palatine artery supply the inferior anterior septum.

The SPA, a terminal branch of the IMA from the external carotid artery, supplies blood to up to 90% of the nasal mucosa.

The network of vessels found in the Little area on the anterior septum is known as the Kiesselbach plexus ( Fig. 3.2A and Fig. 3.2B ). It has a rich blood supply from the anterior ethmoid artery and the SPA.

(A) and (B) Endoscopic views of the Kiesselbach plexus in the Little area.

The Woodruff plexus is located at the posterior 1 cm of the nasal floor, inferior meatus, inferior turbinate, and middle meatus ( Fig. 3.3 ). It is predominantly supplied by the SPA.

Endoscopic view of the Woodruff plexus in the left nasal cavity.