Prerhinoplasty Facial Analysis

An enormous demand for plastic and reconstructive surgery exists in the United States, with over 213,000 rhinoplasty operations being performed in this country in 2018. ^[1] As the most anterior projecting facial feature, surgical alteration of the nose is a common request in facial plastic and reconstructive surgery offices. Even small aberrations of this central facial element can lead to major disharmonies in global facial aesthetics. ^[2]

Rhinoplasty is among the most challenging of all plastic surgical operations. Countless techniques have been developed to creatively alter the size, shape, and function of the nose. The experienced rhinoplastic surgeon uses a thorough knowledge of nasal anatomy and facial aesthetics to choose the techniques best suited to each particular nose. In this regard, careful preoperative nasal and facial analysis is necessary to ensure a satisfactory result in rhinoplasty. This article outlines nasal and facial analysis as it pertains to planning for aesthetic and functional rhinoplasty.

Humans have long tried to understand the beauty of the human face. Praxiteles’ Aphrodite from 450 BCE was considered a standard for artistic beauty for several hundred years (see the image below). Ideals of beauty have changed over the last few millennia. Concepts of beauty are built on the foundations of past artists and scholars, as well as innate aesthetic preferences. With the advent of modern media, popular icons have also shaped or have been shaped by the concept of beauty.

The concepts of facial disharmony and disproportion are vital to a discussion of beauty. Disproportionate features lie outside 2 standard deviations from the mean. However, disproportionate facial features may still be harmonious with one another if the global appearance is aesthetically pleasing. In a comparison of 29 separate female nasal measurements, Farkas et al found that 70% of attractive women had nasal measurements that were within 1 standard deviation from the mean. ^[3] The author argues that the proportionate nose in particular allows for more harmonious unity with other facial features that may fall outside of normal proportion.

Interestingly, ideals of beauty are similar across cultures. Cross-cultural consistency results from an evolutionary process linking physically attractive features to biological or social fitness. In humans, estrogen-dependent characteristics of the female body correlate with health and reproductive fitness and are attractive based on several studies. ^{[4, 5]} To evaluate the strength of innate human preferences of facial attractiveness, Perrett et al digitally enhanced female human faces. ^[6] The altered photographs exaggerated the sex-hormone-related cues of youth and fertility in the female face. Subjects from different cultures consistently preferred the digitally feminized faces to the average female face. Although this preference was stronger within the culture, it was also consistent across cultures. ^[7]

Prerhinoplasty evaluation is not complete without a thorough history, which begins with a discussion about patient motivations. Understanding the patient’s perception of the defect, the patient’s motivations, and the patient’s expectations from surgery allows the surgeon to decide if this is amenable to surgical change. Properly motivated patients have a healthy self-esteem and seek restorative changes to the nose. Having realistic expectations of postoperative results as well as the postoperative recovery period sets the stage for positive results. A surgeon’s mastery of the relationship-building phase of the interview results in improved patient satisfaction, reduced legal liability, and better surgical outcomes. ^[8] In the preoperative interview, the surgeon seeks answers to the following questions ^[9] :

• What are the patient’s expectations?

• Are the expectations realistic and reasonable?

• Do I have the ability to fulfill these expectations?

• Can the patient be satisfied?

Patients seeking cosmetic changes to the nose are generally psychiatrically normal, but a brief psychiatric assessment is wise. Body dysmorphic disorder is a psychiatric condition involving preoccupation with an imagined or slight defect in appearance that leads to markedly excessive concern. This preoccupation causes significant distress or impairment in social, occupational, or other areas of functioning. ^[10] In general, cosmetic surgery patients are no more dissatisfied, critical, or preoccupied with their overall appearance than a nationwide sample of Americans. ^[11] However, patients seeking dramatic changes to the nose should be approached with caution, and a psychiatric consult may be warranted. ^[12]

A literature review by Herruer et al indicated that, aside from the presence of body dysmorphic disorder, demographic and psychosocial risk factors for patient dissatisfaction with facial cosmetic surgery include male sex, young age, unrealistic expectations, the presence of minimal deformities, disturbances in personal and family relationships, attempts to address mental issues with multiple cosmetic surgeries, and a demanding, obsessive, or narcissistic personality. ^[13]

Preoperative images of the nose are essential to rhinoplasty surgery. The 6 standard rhinoplasty views are frontal, right/left oblique, right/left lateral, and basal. The frontal, oblique, and lateral views are taken with the patient in the Frankfort horizontal position, wherein the head is positioned so that a line from the superior aspect of the external ear canal (the porion) to the inferior orbital rim is parallel with the horizon (see image below). Lighting should provide for a somewhat harsh view of the nose and should not wash out fine details or shadows. ^[14]

Frontal view

A properly oriented frontal view has the patient in the Frankfort horizontal position with both pinnae showing symmetrically. To assess symmetry, divide the face into vertical fifths and horizontal thirds (see image). The width of each sagittal fifth of the face is approximately the intercanthal distance. The width of the nasal base should also approximate the intercanthal distance.

Dividing the facial height into thirds is also useful to assess facial symmetry. The anterior-most portion of the glabella forms the division between the upper and middle thirds. The subnasale (junction of the columella with the upper lip) forms the division between the middle and lower thirds. The nose should occupy the middle facial third. See the image below.

The nose itself is also described in terms of horizontal thirds. The nasal bones form the upper third, the upper lateral cartilages and dorsal septum form the middle third, and the nasal tip forms the lower third (see image below).

Upper third (nasal bones)

The nasal bones (upper third) should be symmetrical and approximately 75% as wide as the intercanthal distance. Deviations of the bony third are typically treated with osteotomies, whereas bony asymmetries may be treated with rasping or augmentation.

Middle third (midvault)

A line connecting the club head of the eyebrow to the ipsilateral tip-defining point is known as the brow-tip aesthetic line. ^[15] This useful lines should appear gracefully curvilinear, symmetrical, and unbroken along the midvault. The brow-tip aesthetic line is best seen on frontal and oblique views. Deformities from trauma, masses, or prior surgery (eg, an inverted-V deformity) disrupt the brow-tip aesthetic line. A narrow middle third suggests the potential for nasal valve dysfunction.

Lower third (nasal tip)

The symmetry and size of the nasal tip should be recorded in the medical record. A slight supratip break is ideally present at the junction of the middle third and nasal tip. The tip shape may be characterized as normal, bulbous, narrow, bifid, boxy, or amorphous.

The concept of an aesthetic diamond is useful when visualizing the tip and was first described by Sheen. ^[15] The elegant tip forms a diamond shape composed of the 2 tip-defining points, the supratip break (vertically) and the infratip lobule break (in the midline). The domes of the medial crura should diverge from each other at 50-60º. Narrow divergence causes the tip-defining points to be too close together and gives a pinched or “unitip” appearance. The position and fullness of the lateral crura of the lower lateral cartilages is noted as it contributes to bulbosity. Finally, the nasal rims on frontal view should form a “gull-in-flight” relationship with the columella.

Lateral view

The dominant characteristics of the nasal profile are the projection and rotation of the nasal tip and the dorsal nasal contour. While there are several ways to measure it, projection generally refers to the distance of the nasal tip from the anterior facial plane. The facial plane is defined by an imaginary vertical line connecting the nasion (posterior-most bony point at the root of the nose) with the point where the alar groove intersects the nasolabial fold.

Projection is often examined in relation to the overall nasal length, which is the distance from the sellion (defined below) to the tip-defining point. The normal projection–to–length ratio is 0.55-0.60. Alternatively, the distance from the base of the columella (the subnasale) to the nasal tip should equal the length of the upper lip, if the lip height is normal. Although some surgeons make extensive measurements on preoperative photos, as a practical matter making such calculations at the initial patient encounter is difficult.

Integral to altering nasal length is an understanding of the soft-tissue starting point of the nasal dorsum, termed the sellion (as opposed to the nasion, which is the bony starting point of the dorsum). The sellion represents the soft-tissue vertex of the nasofrontal angle, which is the angle formed between the dorsum of the nose and the beginning of the forehead/glabella. The ideal nasofrontal angle is approximately 120º (see image).

Several authors have offered their opinions about the ideal position of the sellion and consequently the starting point of the nose. Sheen suggested that the sellion be placed at the supra tarsal fold, based on his personal observations over many years of clinical practice. ^[15] However, the position of the supratarsal fold in Caucasians is variable and may be absent in Asian individuals.

In 2004, Mowlavi, et al asked a group of volunteers to evaluate black and white drawings of a female profile that were identical except for the position of the sellion. ^[16] They discovered that the most preferred position differed between men and women judges, and that many different positions were chosen as attractive. However, the most commonly cited position of the sellion by rhinoplastic surgeons is the supratarsal crease. The position of the sellion on lateral view can help to determine whether augmentation of a deficient radix or resection of a dorsal hump is needed.

A straight, high dorsal profile is the currently accepted standard. A slightly scooped appearance of the dorsum in females or a slight dorsal hump in males may be acceptable.

Nasal tip rotation occurs along an arc from the tip-defining point around the porion. An indirect measure of tip rotation is the nasolabial angle, which is the angle formed between the columella and the upper lip. Angles of 90-105° for men and 95-110° for women are considered to be the aesthetic ideal. However, these angles are approximations and narrower angles are appropriate in taller patients. (A study by Sinno et al in which 98 random persons were asked their opinion on the most aesthetically pleasing nasolabial angles indicated that the range falls between 100.9 and 108.9 degrees for female noses and between 90.7 and 103.3 degrees for male noses. ^[17] )

In a female of average height, the shadows inside of the nose should be barely observed above the nasal sill when the facial plane is perpendicular to the Frankfort plane. If the entire sill cannot be viewed, the nose can tolerate rotation. Specific patient or surgeon preferences may modify these guidelines.

The well-defined nasal tip will have a "double-break" with the first break 1-3 mm above the tip-defining point and the second break is at the junction of the infratip lobule and the columella. The nasal tip should lead the nasal dorsum by 1-2 mm, creating a slight supratip break (see the image below). Some surgeons routinely perform a smiling lateral view to document the plunging tip deformity, a condition wherein the tip of the nose plunges with smiling due to contraction of the depressor septi nasi and the levator labii superioris alaeque nasi.

The relationship of the alar rims to the columella should be carefully assessed. The alar rim should arch 2-3 mm above the columella on this view. Deviations indicate alar or columellar retraction that may need to be addressed.

The chin and nose must harmonize to achieve balance of the facial profile. The nose appears more overprojected if the chin is retrusive and vice versa. The zero-meridian is a vertical line that aids in determining if the chin position is adequate. ^[18] The zero-meridian vertical line passes through the nasion perpendicular to the Frankfort horizontal line (see image below).

The pogonion of the masculine chin should approximate or lie just anterior the zero meridian. In women, the pogonion should fall just behind this line. The relationship of the chin to the lower face is assessed with a vertical line from the lower vermilion border of the lip. In men, the pogonion is tangent to this line, with the mentolabial sulcus lying 4 mm posteriorly. In women, this line should lie 2-3 mm anterior to the pogonion. Prognathia or retrognathia is defined by deviation of the pogonion from these positions. If retrognathia or microgenia is present, the patient may be offered chin augmentation.

Oblique view

The right and left oblique images are appropriately oriented when the tip of the nose is tangent to the contralateral malar eminence. These views are ideal for demonstrating the ipsilateral brow tip aesthetic lines (see image below). Further assessments can therefore be made regarding the asymmetries or prominences of the nasal dorsum.

Basal view

To assess the nasal base, the patient's head is tilted back until the nasal tip projects on the midline point between the eyebrows along the axis of the surgeon's view (see image below). The shape of the nasal base is ideally an equilateral triangle. This triangle can again be divided into thirds, with the nostrils comprising the lower two thirds. The remaining third is compose of the infratip lobule. The nostrils should be symmetrical and ovoid in shape. The flare of the medial crural footplates variably and normally causes an indentation in the silhouette of the nostrils. Asymmetry of the nostrils demands a search for an explanation. Possible causes include alar retraction from scar, prior nasal surgery, dislocation of the caudal septum off the maxillary spine, and congenital nostril asymmetry. ^[19]

The width of the alar base is best assessed on the basal view. The ideal width is precisely the intercanthal distance. The base view superimposes the lateral alar margins on the medial canthi, which makes this assessment easy. Note that decreasing tip projection intraoperatively increases alar flare and the width of the alar base, which may necessitate alar base reduction.

The contours and symmetry of the nasal tip are assessed on this view. The elegant tip has a smooth, curvilinear transition from the medial crura to the intermediate crura and tip-defining points. A wide tip is characterized by widely spaced tip-defining points, which leads to a trapezoidal shape of the nasal base. Bifidity of the nasal tip may be observed in widely divergent domal segments in thin-skinned individuals. The base view is useful for confirming impressions of tip projection and symmetry. In assessing projection, the base is visualized with the alar width set at the ideal intercanthal distance. If the triangle formed by the patient's tip position is a long isosceles triangle, the tip is probably overprojected; if shorter, the tip is probably underprojected. Deviation of the columella to one side is often caused by a more posterior caudal septal deviation.

Of the 6 standard views, skin/soft-tissue envelope thickness is best observed on the basal view, although it must always be confirmed by palpation. The lower lateral cartilages of some individuals can be visualized through nearly transparent skin. Thicker-skinned individuals often demonstrate more sebaceous gland hypertrophy and more postoperative edema.

External examination

Observation

Physical examination of the nose begins with observation of the patient during quiet respiration. Note whether the patient is breathing through the mouth or nose. When breathing quietly through the nose, document collapse of the lateral nasal sidewalls if present. The sebaceous gland concentration in the nasal skin is also noted, as are any scars or other asymmetries. The nasal valve is then observed during sniffing. The external valve is formed by the columella medially and the alar sidewalls laterally. External valve collapse may be noted in thin-skinned individuals with narrow nostrils. Collapse of the internal nasal valve is a much more common cause and is discussed below.

Palpation

While much understanding is gained by observing the nose, there is no substitute for nasal palpation. All external areas of the nose must be palpated because a wealth of important information is obtained in this way. Bony and cartilaginous irregularities are identified. The thickness of the skin is verified. Gentle ballottement of nasal tip gives information regarding its structural integrity and support. Knowledge of these characteristics obtained through visual inspection and palpation is absolutely essential for developing a surgical plan.

The thickness of the skin/soft-tissue envelope contributes significantly to postoperative results. ^[20] The final visual result in nasal contour is an interaction between the soft tissue envelope and the underlying bony and cartilaginous skeleton. Meticulous shaping of the nasal skeleton is hidden under thick skin and may result in loss of elegant tip detail. Conversely, though thin skin shows the details of the underlying skeleton, minor imperfections in tip symmetry and contour are also visible. Most patients lie on the continuum between these 2 endpoints.

Ballottement of the nasal tip gives information regarding tip support. The major tip support mechanisms include the size, strength, and resiliency of the lower lateral cartilages, the articulation of the upper with the lower lateral cartilages at the scroll region, and the connection of the medial crural footplates with the caudal septum. ^[21] Ballottement of the nasal tip provides knowledge of the summated effect of the various major and minor support mechanisms. This knowledge is used to guide decisions about surgical maneuvers that may reduce support.

Bidigital manipulation of the caudal septum and its relationship to the medial crura can be obtained by gently grasping and rotating the columella. Deviations of the caudal septum are commonly diagnosed and cause deflection of the nasal tip. If the anterior septal angle can be palpated above the nasal tip and projects above the dorsal contour, then the tension-tip nasal deformity is present. In this case, the anterior septal angle plays a major role in tip support and must be accounted for in the surgical plan.

Internal examination

Nondecongested examination

Improving nasal aesthetics while causing airway compromise or sinus dysfunction does the patient no service. Therefore, performing a speculum examination of the nasal cavity and assessing the nasal airway is important. The internal nasal valve is formed by the caudal edge of the upper lateral cartilage, septum, and the floor of the nose. This area is the single greatest contributor to airway resistance and is examined in every rhinoplasty candidate.

Often the inferior turbinate is hypertrophied and may contribute to nasal obstruction. Septal deflection, fractures, spurs, and other abnormalities are essential to surgical planning for functional rhinoplasty and should be documented. One should also rule out benign or malignant neoplasms as the cause of nasal airway obstruction. If an identifiable cause of nasal obstruction is not found anteriorly, a fiberoptic examination of the nasopharynx should be performed.

Assessing for the presence or absence of septal cartilage is also wise. This is especially important in cases of revision rhinoplasty in which septal cartilage may have been previously harvested. A paucity of septal cartilage may prompt the surgeon to harvest cartilage from other sources.

Specific tests

Superior tip rotation test: Nasal tip ptosis is a common cause of airway obstruction, especially in the older patient. Superior rotation of the tip with a finger while the patient inspires is a helpful maneuver that aids in the diagnosis of this problem. If positive, maneuvers to superiorly rotate and stabilize the nasal tip should be used.

The Cottle maneuver is performed in all patients with nasal airflow obstruction. This is performed by pulling the midfacial soft tissue laterally at the melolabial folds. Improvement in nasal airflow with this maneuver is diagnostic for internal nasal valve collapse. A modified Cottle maneuver may be performed using a cerumen loop to manually lateralize the upper lateral cartilages endonasally. Improvement in nasal airflow during this maneuver is helpful in predicting the success of nasal valve surgery.

Decongested examination

To decongest the nose, topical phenylephrine is applied using an atomizer. The inferior turbinate is examined and compared with the nondecongested state. This helps to determine the contribution of turbinate hypertrophy. With the nasal mucosa decongested, more of the posterior septum and nasal cavity is revealed. Any new septal deflections, septal spurs, or deviations of the perpendicular plate of the ethmoid are noted. The internal and external nasal valves are again examined in the manner outlined above.

Preoperative analysis of the rhinoplasty patient is exceedingly complex but comparably rewarding. Specific directed techniques must be chosen and executed expertly, with the knowledge that each maneuver usually alters several characteristics of the nose at the same time. An appropriate marriage of analysis and technique yields the greatest opportunity for achieving the most important goal of any cosmetic surgery: a satisfied patient.