Introduction

The human nose is a structure used primarily for inhalation and exhalation. The nose is a midline structure — cartilage from both sides of the face form the framework of the nose. Parts of the maxilla bones and palatine bone create the bony structure of the base of the nasal canal. The vomer, ethmoid, and nasal bone make up the roof and walls of the nose and the bony framework. The external appearance of the nose is formed predominately from cartilage.

Since the nose lays in the middle of the face, it has an extensive blood supply. The blood that perfuses the nose is mainly from branches of the facial artery. The branches of the facial artery and the superior labial artery perfuse the nose via the septal branches, the angular artery, the external nasal artery, the dorsal nasal artery, and the lateral nasal artery. The nose also receives blood from arterial anastomoses adjacent to the nose. The lateral nasal artery predominately perfuses the structures that make the external appearance of the nose.

Structure and Function

The facial artery is responsible for perfusing the middle face region, including the nose — the facial artery branches into the lateral nasal artery. The lateral nasal artery is one of the arteries responsible for perfusing the nose. The lateral nasal artery branches from the facial artery and ascends the nose parallel to the ala of the nose. The lateral nasal artery travels toward the tip of the nose. The lateral nasal artery forms anastomoses with the septal branches of the superior labial artery, the angular artery, the ophthalmic artery, the internal maxillary artery, and some of the smaller arteries on the surface of the nose. The lateral nasal artery also provides perfusion to deeper structures of the nose, such as the cartilage.

The lateral nasal artery perfuses the skin on the surface of the nose. The lateral nasal artery also perfuses the cartilage that makes up the nose. The lateral nasal artery forms anastomose with the contralateral lateral nasal artery. The structures that surround the nose receive perfusion from the lateral nasal artery via the anastomoses. The lateral nasal artery provides collateral blood flow to the lip via the anastomosis with the columellar artery and the septal branches of the superior labial artery. The anastomoses form a network around the region of the nose and the bordering cheek. This network is a way the facial artery can provide collateral blood supply to the contralateral facial artery.

Embryology

During embryology, the brachial apparatus will form the structures in the face and neck. The aortic arches will form in parallel with the brachial apparatus. The aortic arches will develop into arteries in the face, neck, and chest. The third aortic arch will form the common carotid artery. The common carotid artery ascends the face and branches into the external carotid artery and the internal carotid artery. The internal carotid artery will ascend into the cranial valve to perfuse the brain. The external carotid artery ascends and perfuses the face via its branches. The external carotid artery branches into the facial artery around the mouth. The facial artery gives rise to the lateral nasal artery. The lateral nasal artery will eventually ascend the nose to perfuse the nose region.[1]

Blood Supply and Lymphatics

The lateral nasal artery will predominately perfuse the nose. The skin on the nose and the cheek bordering the nose also received blood from the lateral nasal artery. The muscles on the nose and the muscles adjacent to the cheek will receive blood from the lateral nasal artery. The extensive network of anastomoses perfuses the middle face region.

The lymph drainage around the nose will drain into facial lymph nodes. These facial lymph nodes will either drain toward the preauricular lymph nodes or the submandibular lymph nodes. Then the lymph will eventually drain back into the central circulation via the right lymphatic duct or the thoracic duct. The right lymphatic duct will drain the right half of the face while the thoracic duct drains the left.

Nerves

The blood supply from the lateral nasal artery provides blood to the distal parts of the cranial nerve I (olfactory nerve).[2] The ophthalmic branch of the cranial nerve V (trigeminal nerve) gives off the nasociliary nerve. The nasociliary nerve branches of the ophthalmic nerve will descend along the roof of the nasal cavity and derive its blood supply from the lateral nasal artery.

Muscles

The lateral nasal artery perfuses the muscles on the nose and the muscles bordering the nose directly. The nasalis muscle and the levator labii superioris alaeque nasi muscle receives blood from the lateral nasal artery directly.[3] The other muscles in the cheek region close to the nose may be perfused by the lateral nasal artery indirectly. The lateral nasal artery may provide blood to the other muscles in the face also via the anastomoses.

Physiologic Variants

The branching of the facial artery into the lateral nasal artery is variable. In the majority of individuals, the lateral nasal artery will come from the bifurcation of the facial artery into the superior labial artery and the lateral nasal artery close to the corner of the vermillion border. The lateral nasal artery sometimes is a direct branch of the superior labial artery instead of the facial artery. If the lateral nasal artery is a branch of the superior labial artery, it will ascend the face parallel to the nose until it reaches the ala. At the region of the ala, the lateral nasal artery will then ascend the nose.[4] 

The network of arterial connections around the nose region and bordering cheek varies greatly. 

Surgical Considerations

The knowledge of the blood vessel and anastomoses around the nose can be used to reconstruct this region if it becomes damaged. The anastomoses system in the nose is important to know when it comes to rhinoplasties. Since the compression or compromise of one artery in the nose will most likely result in no deficits. The reason there are no deficits is because of the network of collateral blood flow.[5] This knowledge can be expanded and used in facial fillers. The injection of fillers may result in damage or compromise blood vessels around the nasal region. But the collateral circulation rescues the tissue that would have suffered if their main blood supply is lost.[6] 

The columellar reconstruction uses the pedicle of skin and tissue in the nasolabial fold. The nasolabial fold that is perfused by the lateral nasal artery can be used to reconstruct the columella. The tissue flap that is perfused by the lateral nasal artery can be reversed and rotated into the columellar region.[7] 

The lateral nasal artery perforator flap can also be used to reconstruct the nasal walls. The flap of tissue that contains the perforated arteries from the lateral nasal artery can be dissected and rotated to create a new nasal wall if needed.[8][9][10]

Clinical Significance

The blood supply to the nose and nasolabial fold region is from a network of arteries. If these vessels were to become damaged from trauma and result in bleeding, the compression time to achieve hemostasis could be longer. The reason that hemostasis is prolonged is due to collateral blood flow. But a key benefit in the collateral blood flow is that the damaged tissue will heal faster due to the extensive blood supply.

Other Issues

Since the lateral nasal artery is a branch of the facial artery, if there were to be any damage or compromise of the facial artery or the more proximal blood supply, the lateral nasal artery will become affected. If the lateral nasal artery suffers compromise, there could be potential for ischemia of the nose. Ischemia affects the nose region if the collateral blood supply is inadequate.