Ideal Nose
Revision Beauty remains a subjective perception influenced by numerous societal and interpersonal factors, and the recognized or unrecognized assessment of facial proportions. For example, the Greeks sought to describe beauty according to a collection of mathematical lines or angles. This Grecian philosophy has led to the development of the general principle that human faces judged to be attractive possess greater degrees of symmetry. The perception of beauty is further enhanced by interpersonal factors, such as age and personality. This multidimensional nature of beauty creates a significant challenge for facial plastic surgeons to provide patients with a satisfactory perception of attained personal beauty. As such, facial plastic surgeons must rely not only on technical skills, but also on the complementary integration of artistry to achieve symmetry, harmony, balance, and proportion.
Proportions of the Aesthetic Face
Universally accepted guidelines and measurements of facial proportions exist, but represent only basic standards for facial evaluation and analysis. The facial plastic surgeon must be aware of these proportions and their mathematical values, and also understand their limitations in the clinical setting. The primary goal of aesthetic surgery is to create a non surgical, natural appearance for any given patient. Rigid adherence to calculated proportions may limit success in achieving this goal.
Reference Points
A basic knowledge of standard reference points, measurements, and their normative values for computer imaging, record keeping, photography, and for communication with colleagues is invaluable. These have been standardized by Powell and Humphreys. The definition of key points for analysis is listed in Table 1. The Frankfort horizontal plane is the standard reference used for patient evaluation and photography. It represents a line drawn from the superior aspect of the external auditory canal to the most inferior point on the infra orbital rim while the patient’s eyes are parallel to the floor (Fig. 2). A soft tissue definition for the inferior point on the infra orbital rim is the point of transition between lower eyelid and cheek skin.
Facial Analysis
The initial assessment of the face evaluates facial symmetry. When comparing facial symmetry between the halves through a midsagittal plane, minor asymmetries are noted in most people. Facial width is evaluated by dividing the face into fifths. The width (fig. 3). Lines dropped from the lateral canthus should approximate the width of the neck.
Facial height can be assessed in two ways. The first method is to divide the face into three equal parts (Fig. 4). Measurements are made in the midline from the trichion (Tr) to the glabella (G), G to the subnasale (Sn), and Sn to the menton (Me). The second method excludes the upper third of the face. This method disregards forehead height, because it varies with secondary changes in hairline position. Measurements are made from the nasion (N) to Sn, representing the midfacial or nasal height (43%) and from Sn to Me, representing the lower facial height (57%) (Fig. 5).
The face is then subdivided into the following major aesthetic units for further analysis: forehead, eyes, nose, lips, chin, ears, and neck.
Nose
The nose is the central aesthetic unit of the face; creating a high demand for nose surgery. It can be divided into five topographic subunits: (1) dorsum, (2) sidewalls, (3) tip, (4) ala, and (5) soft triangles (fig. 8). The borders of the subunits allow for scar camouflage when reconstructing nasal defects. If incisions lie along the margins of these anatomic subunits, the scar is less noticeable.
When examining the nose and its relationship to the other facial structures, one must consider numerous factors. These include age, gender, race, body habitus, facial contours, hair, lip support, dentition, cephalometrics, facial deformities, symmetry, skin character, and effects of contour changes. These factors have a direct impact on nasal evaluation and aesthetics.
Naso facial Relationships
Powell and Humphreys formulated relationships between the nose and face. They include the nasofrontal angle, nasolabial angle, nasofacial an angle, and nasomental angle. The nasofrontal angle is created at the transition between the forehead and nose. The angle is formed between a line tangent to G through N that intersects with a line tangent to N and the nasal dorsum (Fig. 9). The range for this angle should be 115 to 130 degrees. The nasolabial angle defines the angular inclination of the columella as it meets the upper lip. The angle is formed between the intersection of a line tangent to the labrale superius (Ls) and Sn and a line tangent to Sn and the most anterior point on the columella (Fig. 10). This angle should measure 95 to 110 degrees in women and 90 to 95 degrees in men. The nasofacial angle is the incline of the nasal dorsum in relation to the facial plane. The nasofacial angle ideally measures 36 degrees with a range of 30 to 40 degrees. It represents the angle formed from a vertical line tangent to the forehead at G to the pogonion (Pg), named the anterior facial plane, intersecting a tangential line from N to the nasal tip (Fig. 11). The nasomental angle describes the angle between a tangent line from N to the nasal tip intersection with one from the tip to Pg. The range for this angle is 120 to 132 degrees (Fig. 12). The nasomental angle correlates nasal tip, chin, and forehead projection.
Nasal projection and Rotation
Nasal projection and rotation are measurements or illusions of measurements that go hand in hand. One must understand these concepts together when evaluating the nasal complex. Tip rotation generally occurs along an arc produced by a radius based at the external auditory canal (Fig. 13). In tip rotation, the radius line moves superiorly or inferiorly as the tip is raised or lowered. An illusion of the tip rotation may be gained by removing a dorsal hump.
More than one method can be used to quantify nasal projection. Simons measures tip projection in relation to the length of the upper lip. Nasal projection is approximately equal to the length of the upper lip, giving a ratio of 1:1. The upper lip is measured from Ls to the base of the columella at Sn. The length of the nasal tip is measured from Sn to the most anterior point on the columella (Fig. 14). Goode’s method uses a vertical line drawn from N to the alar groove to the nasal tip, and a line from N to the nasal tip. The ratio comparing the length of the perpendicular line (alar groove to tip) with that of the nasal length (N to tip) should be 0.55 to 0.60 (Fig. 15). When these ratios are observed, the nasofacial angle is approximately 36 degrees.
Nasal Length
Nasal length has been discussed utilizing numerous methods, such as the nasofacial angle, Goode’s nasal projection, and in its relationship to facial proportions.
Nasal Width
The nasal width is approximately one eye width at the base. Vertical lines drawn from the medial canthus down the face to the ala should approximate the nasal width in a well-proportioned nasal base (see Fig. 3). An alternative method for determining nasal width is to measure lateral ala to lateral ala. This value should be approximately 70% of the nasal length (N to tip).
Basal View
The nares are ovoid and obliquely slanted toward the nasal tip. The nasal base can be described as an equilateral triangle with the columella at its centermost portion. On frontal view, the nares should be barely visible when the head is in a neutral position. The contour of the nasal tip and nares on frontal view has been described as a gull-in-flight (Fig. 16). The tip and nares represents about one third and two thirds of the total height of the nasal base, respectively.
Lateral View
On lateral view, the ala-to-tip lobular complex ratio is considered optimal at 1:1 (see Fig. 16). Columellar show of 3 to 5 mm is considered acceptable (see Fig. 16). The supratip break is described as a depression just cephalic to the nasal tip where the lobule meets the caudal cartilaginous dorsum. This subtle break is considered aesthetically pleasing and is more pronounced in women. Additionally, the nasal tip has a double break produced by the tip-defining point of the lobule interiorly and the lobular-columellar junction inferiorly.
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