Skin type

The native skin quality influences the operative plan and subsequent techniques performed.

First, skin type, thickness, and texture are assessed.

Thicker skin will tend to camouflage changes to the underlying osseocartilaginous framework, and may therefore allow a more ‘aggressive’ surgery to demonstrate an appreciable change. Patients who have thicker skin that has a more sebaceous character tend to have more postoperative edema, especially in the tip or lobule area.

Thinner skin tends to reveal even minor changes to the underlying framework. Therefore patients who have thinner skin can be more challenging because there is less margin for error.

Systematic analysis of the nose and face

Next, a systematic analysis of the nose and face is undertaken.

Look for potential anomalies of the underlying facial skeleton

Initially we evaluate potential anomalies of the underlying facial skeleton, including the maxillomandibular relationship.

We divide the face into thirds using horizontal lines adjacent to the:

The upper one-third is the least important because it is the most variable.

The lower one-third of the face is then subdivided into thirds by visualizing a horizontal line between the oral commissures (stomion):

If there are disproportions, the patient may have underlying craniofacial anomalies (e.g. vertical maxillary excess) that necessitate correction.

The nasal length (radix to tip [RT]) should be equivalent to the stomion-to-menton distance (SM), as described by Byrd and Hobar.

A natural horizontal facial plane is determined by drawing a line perpendicular to a plumb line superimposed over the head in repose and the eyes in straightforward gaze. This will serve as a future point of reference (Fig. 11.2).

Fig. 11.2 A natural horizontal facial plane. This is determined by drawing a line perpendicular to a plumb line superimposed over the head in repose and the eyes in straightforward gaze.

The lip-chin relationship is assessed by dropping a vertical line from a point one-half the ideal nasal length tangential to the vermillion of the upper lip. The lower lip should lie no more than 2 mm behind this line (Fig. 11.3). The ideal chin position is gender dependent. The female chin should be slightly posterior to the lower lip, but equal to the lower lip in men. Discrepancies in these relationships may warrant orthodontics, orthognathic surgery, or a chin implant.

Fig. 11.3 The lip-chin relationship. This is assessed by dropping a vertical line from a point one-half the ideal nasal length tangential to the vermillion of the upper lip. The lower lip should lie no more than 2 mm behind this line.

Nasal features

Frontal view

Nasal deviation is evaluated by drawing a line from the mid-glabellar area to the menton, bisecting the nasal ridge, upper lip, and Cupid’s bow. This line will also pass between the central incisors when occlusion is normal. Any deviation of the nose from this line will likely require septal surgery.

The nasal dorsum is then assessed. The curvilinear dorsal aesthetic lines are traced from the origin at the supraorbital ridges to the tipdefining points, slightly diverging from each other along the dorsum during their course. Ideally, the width of the dorsal aesthetic lines should match the width of either the tip defining points or the interphiltral distance.

A relationship between the bony base width and the alar base is then assessed. The bony base width should be 80% of the normal alar base width, and a normal alar base width 2 mm wider than the inter-canthal distance, or the width of one eye (Fig. 11.4A&B). If the bony base is greater than 80% of the alar base width (assuming the alar base width is normal), osteotomies will be required to narrow the dorsum. Males tend to have a wider bony base than females and it is important not to over-narrow the male dorsum creating a feminized result.

Fig. 11.4 The width of the bony base relative to the alar base is then assessed.

A, The bony base width should be 80% of the normal alar base width. B, A normal alar base width is equal to the intercanthal distance or the width of one eye.

Next the alar base and alar rim are analyzed. If the alar base width is over 2 mm and greater than the intercanthal distance, it must be determined whether the cause is a narrow intercanthal distance, a true increased interalar width, or alar flaring:

• if the intercanthal distance is smaller than one eye width, it is better to maintain a slightly wider alar base;

• if there is true increased interalar width, a nostril sill resection may be indicated;

• if the increase in width is secondary to alar flaring (>2–3 mm outside the alar base), an alar base resection should be considered.

The alar rims should also be assessed for symmetry, and should flare slightly outward in the inferolateral direction.

The tip is assessed to determine:

• the supratip break;

• the tip-defining points;

• the columellar-lobular angle (Fig. 11.5).

Fig. 11.5 Frontal view of the nose. The tip is assessed to determine the supratip break, the tip-defining points, and the columellar-lobular angle. These points serve as landmarks to draw two equilateral triangles with their bases opposed.

These points serve as landmarks to draw two equilateral triangles with their bases opposed. If these triangles are asymmetric, the underlying reason should be investigated, and the patient will likely require tip modification.

The final assessment on frontal view is of the outline of the alar rims and the columella, which should resemble a seagull in gentle flight, with the columella lying just inferior to the alar rims. If the curve is too steep, the patient likely has an increased infratip lobular height, which will need correction. If, on the other hand, the curve is flattened, it is likely the patient has decreased columellar show which may require columellar augmentation or alar rim modification.

Basal view

The basal view of the nose is addressed next, with the outline of the nasal base describing an equilateral triangle with a lobule-to-nostril ratio of 1 : 2 (Fig. 11.6). The nostril itself should have a teardrop-like geometry, with the long axis from the base to the apex oriented in a slight medial direction.

Fig. 11.6 Basal view of the nose. The outline of the nasal base describes an equilateral triangle with a lobule-to-nostril ratio of 1 : 2. The nostril itself should have a teardrop-like geometry, with the long axis from the base to the apex oriented in a slight medial direction.

Lateral view

The lateral view is then analyzed, beginning with the position and depth of the nasal root at the nasofrontal angle (radix). This angle connects the brow and the dorsum through a soft concave curve. The apex of this angle should lie between the upper lid eyelashes and the supratarsal fold, with the eyes in natural horizontal gaze. Although this angle can vary from 128 to 140 °, it is ideally 134 ° in females and 130 ° in males. Other important reference measurements from this view include:

• the nasion-medial canthal distance, which should be approximately 15 mm;

• the nasion-corneal plane distance, which is approximately 11 mm.

While still concentrating on the lateral view, it is important to remember that the perceived nasal length and tip projection can be altered by the position of the nasofrontal angle. For instance, if the nasofrontal angle is positioned more anteriorly and superiorly than normal:

• the nose will appear elongated;

• the nasofacial angle will be decreased;

• the tip projection will appear diminished (Fig. 11.7).^14,15

Fig. 11.7 The nasofrontal angle. If the nasofrontal angle is positioned more anteriorly and superiorly than normal, the nose will appear elongated, the nasofacial angle will be decreased, and the tip projection will appear diminished (yellow line). If the nasofrontal angle is too posteriorly and/or inferiorly positioned, the nose will appear shorter, and the tip more projecting (red line).

On the other hand, if the nasofrontal angle is too posteriorly and/or inferiorly positioned, the nose will appear shorter, and the tip more projecting. Ideally, the nasofacial angle (as defined by the junction of the nasal dorsum with the vertical facial plane) should measure 32–37 °.

Tip Projection

Tip projection is addressed on the lateral view. We describe two methods to accomplish this.

• For the patient with normal upper lip projection, a line is drawn from the alar-cheek junction to the tip of the nose. Tip projection is considered normal if 50–60% of the tip lies anterior to a vertical line adjacent to the most projecting part of the upper lip. The tip is considered to be overprojecting if greater than 60% of the tip lies anterior to this reference line, and may require reduction. If less than 50% of the tip lies anterior to the line, the projection may need to be augmented (Fig. 11.8).

• The second method we use to help assess tip projection is by comparison with the alar base width (which should be equal), as well as by comparing the ratio of nasal length (RT) to the tip projection (alar base-to-tip); ideal tip projection is 0.67 × RT (Fig. 11.9A&B).

Fig. 11.8 Tip projection. Draw a line from the alar-cheek junction to the tip of the nose. Tip projection is considered normal if 50-60% of the tip lies anterior to a vertical line adjacent to the most projecting part of the upper lip. The tip is considered to be overprojecting if greater than 60% of the tip lies anterior to this reference line, and may, therefore, require reduction. If less than 50% of the tip lies anterior to the line, the projection may need to be augmented.

Fig. 11.9 Other methods for assessing tip projection. A, A second method we use to help assess tip projection is by comparing it to the alar base width – they should be equal. B, When comparing the ratio of nasal length (radix-to-tip [RT]) to the tip projection (alar base-to-tip), the ideal tip projection is 0.67 × RT.

Dorsum

The dorsum is then analyzed. The ideal nasal dorsum should lie approximately 2 mm behind and parallel to a line from the radix to the tip-defining points in women, but should be slightly higher in men to avoid feminizing the nose (Fig. 11.10).

Fig. 11.10 Analyzing the dorsum. The aesthetic nasal dorsum should lie approximately 2 mm behind and parallel to a line from the radix to the tip-defining points in women, but in men it should be slightly higher to avoid feminizing the nose.

Supratip Break

The degree of supratip break is appraised when the nasal tip projection and dorsum are evaluated. A slight supratip break is preferred in women but not in men. This gives the nose more definition and distinguishes the dorsum from the tip.

Tip Rotation

The nasolabial angle is used to determine the degree of tip rotation. This angle is obtained by measuring the angle between a line coursing through the most anterior and posterior edges of the nostril and a plumb line dropped perpendicular to the natural horizontal facial plane. This angle should be between 103–105 in women and 95–100 in men (Fig. 11.11).

Fig. 11.11 Tip rotation. The nasolabial angle is used to determine the degree of tip rotation. This angle is obtained by measuring the angle between a line coursing through the most anterior and posterior edges of the nostril and a plumb line dropped perpendicular to the natural horizontal facial plane. This angle should be between 95 and 100 ° in women and between 90 and 95 ° in men.

Do not confuse the nasolabial angle with the columellar-labial angle, which is formed at the junction of the columella with the infratip lobule. This angle is normally 30–45 ° (Fig. 11.12). Increased fullness in this area is usually caused by a prominent caudal septum giving the illusion of increased rotation, even though the nasolabial angle is normal.

Fig. 11.12 Illusion of increased tip rotation. Do not confuse the nasolabial angle with the columellar-labial angle, which is formed at the junction of the columella with the upper lip/infratip lobule. Increased fullness in this area is usually caused by a prominent caudal septum and gives the illusion of increased rotation, even though the nasolabial angle is normal. This angle is normally between 30 and 45 °.

Alar-columellar relationship (lateral and frontal views)

The alar-columellar relationship is then assessed.

A line is drawn through the long axis of the nostril, and a perpendicular line drawn from alar rim to columellar rim that bisects this axis. The distance from the alar rim (point A) to the long axis line (point B) should equal the distance between the long axis line to the columellar rim (point C) if the alar-columellar relationship is normal (Fig. 11.13).

Fig. 11.13 Alar-columellar relationship. A line is drawn through the long axis of the nostril, and a perpendicular line drawn from alar rim to columellar rim that bisects this axis. The distance from the alar rim (point A) to the long axis line (point B) should equal the distance between the long axis line to the columellar rim (point C) if the alar-columellar relationship is normal (AB = BC−2 mm).

If these measurements are not normal, nasal dismorphology can be categorized into six classes:^16,17

• classes I-III describe increased columellar show;

• classes IV-VI demonstrate decreased columellar show (Figs 11.14A-F).

Fig. 11.14 Abnormal alar-columellar relationships. A-C, Classes I-III describe increased columellar show. D-F, Classes IV-VI demonstrate decreased columellar show.

Differences between male and female noses

The proportions given above generally apply to Caucasian women. Generally, the male face tends to have a squarer, less rounded appearance, with stronger more pronounced features. The key differences in males are summarized in Box 11.2.⁷

Box 11.2 Key features of male noses (compared with female noses)*

• Dorsum tends to be straighter and wider with decreased concavity at the superciliary ridges

• Nasal dorsal profile (a line drawn from the radix to the tipdefining points) should approach 1 mm or less, instead of falling 2 mm behind and parallel to this line in women

• No supratip break

• Tip rotation slightly less (95–100 ° vs 103–105 ° in females) because less nostril show secondary to a longer nasal dorsum

• Stronger chin abutting the plumb line drawn tangential to the upper lip (vs 2–3 mm posterior to this line in women)

• Broader, more bulbous, nasal tip, in general

• Skin is usually thicker, masking the amount of change that can be perceived.

^* These proportions are general guidelines and vary between gender and racial origin. They are only meant to be used as a systematic method of analysis with general proportions and relationships. Each nose should be individualized to the patient’s facial structure and tempered by their desires to create nasofacial harmony and balance.

Skin

The thickness, mobility, and sebaceous character of the nasal skin vary along its length, with the upper two-thirds being thinner, more mobile, and less sebaceous than the inferior one-third.¹⁸

The nasal dorsum thickness averages approximately 1300 μm, whereas the lobule skin thickness averages 2400 μm. A straight dorsum actually has a slight underlying convexity of its osteocartilaginous framework in the cephalic area; therefore a straight dorsal profile is actually produced by the combination of this convexity in the osteocartilaginous framework with the variation in dorsal skin thickness.

Some ethnic subgroups, such as Africans, Hispanics, and those of Mediterranean descent, can have thicker, more sebaceous skin. These differences are important because the skin over the underlying nasal framework can either reveal or mask changes depending on its characteristics. For instance, it is advisable to err on the conservative side when operating on a Caucasian woman with thin skin compared with a man of African descent who has thick, sebaceous skin. More dramatic changes to the underlying framework are tolerated in the patient who has thick skin to obtain an appreciable change in the external appearance.

Muscles

Two muscles, in particular, are important in rhinoplasty:

Fig. 11.15 Levator labii alaeque nasi and the depressor septi nasi. These two muscles are important in rhinoplasty.

Evaluation of the depressor septi nasi is routine in our preoperative assessment. Its effect on depressing the nasal tip and shortening the upper lip can be appreciated in some patients on animation (especially when smiling). In the subgroup of patients in whom this muscle significantly alters the nasal appearance, we dissect and transpose the muscle. By doing so, several goals are achieved:

Blood supply

The vascular supply to the nose is derived from branches of the ophthalmic and facial arteries (Fig. 11.16).

Fig. 11.16 Vascular supply to the nose. This is derived from branches of the ophthalmic and facial arteries.

It is important to note the vascularity to the nasal tip because an open rhinoplasty approach using a transcolumellar incision will transect the columellar vessels (when present), leaving the lateral nasal and dorsal nasal arteries as the remaining blood supply.

In our 1995 study,²¹ we found the lateral nasal arteries to be present (either singularly or bilaterally) in 100% of cases, with the columellar branches present 68.2% of the time.

The lateral nasal vessels are found approximately 2–3 mm above the alar groove, so extended alar resections to this level are prohibited because injury to these vessels after the transcolumellar approach would severely compromise blood flow to the nasal tip. Furthermore, be cautious when debulking the nasal tip after an open approach because the subdermal vascular plexus connecting the dorsal nasal and lateral nasal blood supplies may be damaged, leading to a similarly disastrous result.

Toriumi et al.²² studied the vascular and lymphatic anatomy of the nose and determined that the transcolumellar incision itself did not compromise major venous or lymphatic outflow. Furthermore, they recommend dissection just above the perichondrium in the deep areolar plane, leaving the musculoaponeurotic layer intact, which preserves the major arterial vascular supply and avoids damage to the venous and lymphatic vasculature that lies in a more superficial (subcutaneous) plane. In this way, bleeding and postoperative edema are minimized.

Nasal vaults

The osteocartilaginous nasal framework can be subdivided into three separate vaults: bony, upper cartilaginous and lower cartilaginous.

Bony vault

The bony vault (Fig. 11.17) constitutes the upper one-third to one-half of the nose and is made up of the paired nasal bones and the ascending frontal process of the maxilla. It is important to note that the nasal bones are narrowest and thickest above the canthal level. As a result, osteotomies are rarely indicated above this level.

Fig. 11.17

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