Introduction and Anatomy

The nose is arguably the most prominent feature of the face. It is made up of a fixed part (formed by the frontal notch, parts of the zygomatic and nasal bones, the upper lateral cartilage and the septum) and a mobile part (formed by the lower lateral cartilage and the lower part of the upper lateral cartilage). When planning aesthetic enhancement procedures, we must consider the nose as a stand-alone unit with its specific volumes as well as a part of the face with specific ratios that have to be respected to achieve overall facial harmony.

The two key angles that are crucial in achieving this harmony are: 

  1. Nasofrontal angle: This is assessed on profile view and reflects the angle between the glabella and the dorsum of the nose. Ideally, this should be between 115-135 degrees (Fig. 1) 
  2. Nasolabial angle: This angle, also assessed on profile view, is formed between the columella and the upper lip. This should be between 90-105 degrees in men and 105-115 degrees in women. (Fig. 1) 

Fig 1: Nasofrontal and nasolabial angles. 

In addition, enhancement of the lips and chin with dermal fillers can also help us achieve overall facial harmony. In certain cases, the nose may appear smaller or less protruding when balanced correctly with chin and lips enhancements (medical profilopasty). 

The layers of the nose, from superficial to deep include: 

  1. Skin – the skin is thin at the nose bridge and gets progressively thicker towards the tip. In the mobile part, the skin also has more dense sebaceous glands. 
  2. Cellular Subcutaneous Tissue this layer is relatively underdeveloped and forms a clear layer with very little fat in the mobile part of the nose.  
  3. Muscles this layer contains elevator, depressor, compressor and dilator muscles for the nostrils.  
  4. Perichondro-Periosteal Envelope this layer is made up of interconnected fibres and holds together the structures of the nasal pyramid.  
  5. Vessels and Nerves – vessels are generally small and located at the sides of the nose. Motor branches of the facial nerve are interconnected through the nasal SMAS to supply the muscles. 

The vascular network of the nose originates from both the external and the internal carotid arteries via the facial artery and ophthalmic artery, respectively. The facial artery and its course along the nasolabial fold are categorized as 1 of 3 types, as described by Saban and colleagues. In their study using cadavers and ultrasound imaging, they found that in 80% of the cases the artery coursed medial to the nasolabial fold (type I). In 15% of the cases, the artery coursed into the cheek, lateral to the nasolabial fold (type II). In 5% of cases, they found the facial artery terminated in the parasymphyseal region, with the contralateral facial artery providing vascular supply to both sides of the nose (type III).

There are 4 constant arteries:

  • The subnasal artery
  • Angular artery
  • Dorsal nasal artery
  • Lateral nasal artery

The subnasal artery branches at the alar-facial recess and courses medially to the lower columella, where it extends superiorly to the nasal tip as the columellar artery (anastomosis with philtral artery from the superior labial artery). The marginal artery is a terminal branch of the facial artery (83%) or lateral nasal artery coursing along the caudal border of the lower lateral cartilage (LLC). The marginal artery shares multiple anastomotic arcades with the lateral nasal artery over the lateral crus of the LLC. The lateral nasal artery, as described by Toriumi and colleagues, courses along the cephalic border of the LLC and anastomoses with the columellar arteries at the nasal tip. The angular artery runs vertically toward the medial canthus, where it anastomoses with the ophthalmic arterial system. The internal carotid system gives rise to the ophthalmic artery, and therefore, the dorsal nasal artery anastomotic arcade. The dorsal nasal artery runs vertically along the dorsum of the nose, whereas the radix artery is oriented horizontally, with branches anastomosing to the contralateral system. Saban and colleagues simplify the arterial supply to the nose into a polygonal system based on 4 transfacial arcades. The intercarotid anastomosis of the angular and dorsal arteries provides the vertical systems with the radix, lateral nasal, marginal, and subnasal artery providing the horizontal or transfacial anastomoses (Fig. 3).

Fig. 3. Polygonal system. (From Saban Y, Andretto Amodeo C, Bouaziz D, et al. Nasal Arterial Vasculature: medical and surgical applications. Arch Facial Plast Surg 2012;14(6): 429-36;)

In the nose, fillers with a higher G’ tend to be more effective than those with a lower G’. G’ is known as the elastic modulus, and it is a representation of the ability of a filler to resist deformation. Stiffer fillers, such as a high G’ , large-particle HA gel, more closely mimic natural bone and cartilage, yielding results that are more defined, precise, and sharp. Softer, more pliable fillers can provide width to the placement areas without as much height or definition.

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