The nose should be assessed from the 1) frontal, 2) lateral, and 3) basal views.
Symmetry – A lack of symmetry of the nose may be a sign of a deviated septum (the cartilage that separates the right and left nostrils). A deviated septum is often associated with difficulty breathing.
Dorsal Aesthetic Lines (DAL) – Ideally, the bridge of the nose should be contoured by two slightly curved lines that are symmetric and smooth.
Nasal length – Generally, the length of the nose should be roughly equal the height of the forehead and the lower portion of the face.
Width of Alar Base (Distance between the outer edges of the nostrils) – The width of the alar base should be equal to the distance between the two inner corners of the eyes.
Width of Bony Base (Width of the bone in your nose) – The width of the bony base should be 75-80% of the alar base width.
Alar Rims (Outline of nostrils) – The alar rims should have a slight outward flare and take on the shape of seagull wings with a gentle curve.
Tip Shape – The tip of the nose can be marked using four landmarks at the supratip break (the point where the bridge and tip meet), right below the nose, and on either side of the tip. Straight lines that connect these four points should resemble two equilateral triangles that face opposite directions. This analysis can reveal a bulbous or pinched nose.
Nasofrontal Angle – The angle is formed at the juncture where the line from the glabella (forehead) to the nasion (bony depression between the eyes) crosses the line from the nasion to the tip. This angle should be between 115-130 degrees and is usually greater in females than males. A large nasofrontal angle can give an illusion of a long nose, while a small nasofrontal angle may create the illusion of a short nose.
Dorsal Profile – The dorsal profile can be smooth, convex (humped), or concave (scooped-out). In females, a slight concavity is often preferred, whereas, in males, a minor dorsal hump may be acceptable or even desirable.
Supratip Break (point where the nasal bridge and tip meet) – A slight supratip break enhances nasal definition and distinguishes the dorsum from the tip. A supratip break is often preferred in women but not in men.
Tip Projection - To assess nasal tip projection, a line is drawn from the base of the nostril to the tip of the nose. Tip projection is considered adequate when 50-60% of the nasal projection is in front of the most projected part of the upper lip. If it is greater than 50-60%, the tip may be over-projected and require reduction.
Tip Rotation - The nasolabial angle is measured at the juncture between the columella (the tissue between the nostrils) and the upper lip and can be used to assess tip rotation. The ideal nasolabial angle is between 90-120 degrees. A more obtuse angle within this range is preferred in women, while an angle closer to 90 degrees is preferred in men.
Columellar-Lobular Angle - The columellar-lobular angle, which is formed at the juncture between the columella (the tissue between the nostrils) and the bottom-most part of the tip is considered normal at 45 degrees An acute columellar-lobule angle is often associated with a long upper lip.
Relationship with chin and lips - The upper lip should project about 2mm beyond the lower lip and in most women, the chin will be slightly posterior to the lower lip (2-3mm). In men, the chin may be slightly longer.
Symmetry – Signs of asymmetry or buckling can indicate a deviated septum or signal abnormalities in the underlying cartilage.
Shape – The outline of the nasal base should form a triangle with a slightly tapered apex that is not boxy or bulbous. The ideal tip lobule-to-columella ratio is 1:2.
Nostril Size and Shape – the ideal nostril shape is that of a teardrop with the long axis extending from the base to the apex angled 30 to 45 degrees toward the midline.