Evidence-Based Nasal Analysis for Rhinoplasty

The 10-7-5 Method

Íris M. Brito, MD; Yash Avashia, MD; Rod J. Rohrich, MD

Disclosures

Plast Reconstr Surg Glob Open. 2020;8(2):e2632 

In This Article

Lateral View (7 Key Areas)

Nasofrontal Angle

Two lines tangent to the glabella and to the nasal dorsum, intersecting at nasion, define the nasofrontal angle.[15,35] The degree of nasofrontal angle, vertical position of the radix, and horizontal location of nasion are important profile measures. The nasofrontal angle (radix) should lie between the superior lash line and the supratarsal crease, with the nasion ~15 mm anterior to the medial canthus.[8,15,36] The ideal nasofrontal angle varies by gender, with 130 degrees considered acceptable in White men versus 134 degrees in women.[15,35] Ethnic variability exists as well.[8,15,35] Optimal female noses present a horizontally and vertically lower nasion with concave to straight profile, while optimal male noses have a higher nasion and straight profile.[36]

Nasal Length, Dorsum, and Supratip

The ideal nasal length (nasofrontal angle to the tip-defining points) is equivalent to two-thirds of midfacial height, the stomion-to-menton distance, or to chin vertical.[7,8,37,38] The perceived nasal length and projection can be influenced by the position of the nasofrontal angle.[15] The nose will appear more elongated (with less tip projection) if the angle position is more superior and anterior, versus shorter (more projecting tip) if the angle is more inferior and posterior.[15] Techniques for shortening or lengthening the nose were reported.[22,37,39]

The nasal dorsum should be smooth, with a slight supratip break in women roughly 2–3 mm above the tip-defining points.[8] In male patients, the dorsum should follow a line drawn from the radix to the tip-defining points, while in women, it should be along a parallel line ~2 mm more posterior.[7,15] This evaluation will indicate if dorsum reduction or augmentation is needed.[7] Any dorsal hump and its location should be noted (strictly osseous, osseocartilaginous, or cartilaginous only).[15] Dorsal overresection of these components will result in a scooped out deformity on nasal profile. The anterior septal angle defines the gateway to safely approach the dorsum,[40] and performing the dorsal reduction or augmentation maneuvers required for each patient.[15,41,42]

Balance between the nasal dorsum and the tip-defining points determine the supratip break.[43] A supratip break is accomplished through creating tip-defining points with good projection and reducing the dorsum to the desired effect. The pollybeak (or supratip) deformity is defined as excessive supratip fullness.[44,45] The most important predisposing factor for pollybeak deformity development after primary rhinoplasty is heavy thick skin.[45] Other structural factors may contribute to this deformity, whereas supratip sutures and/or skin excision techniques can be employed to prevent it.[44,45]

Tip Projection

Projection is considered ideal when 50%–60% of the tip lies anterior to a vertical line adjacent to the upper lip or represents 0.67 times the ideal nasal length.[8,38,43,46] The tip can be over or under-projected if it stands above or below to this values. Specific surgical procedures were recommended to control, decrease or increase tip projection.[38,46,47]

Tip Rotation

Tip rotation is determined by the nasolabial angle and should equal ~90 to 95 degrees in men and 95 to 100–110 degrees in women.[7,8] The intersection of a line drawn through the nostril aperture midpoint and other perpendicular to the Frankfort horizontal plane, defines the nasolabial angle.[7,48] Fullness at the columellar-labial angle (curved junction of the columella with upper lip) caused by a prominent caudal septum creates a pseudorotation appearance.[7] Rotation of nasal tip can be achieved by means of several methods, mainly addressing the lower lateral cartilages or caudal septum.[3,48,49]

Alar-columellar Relationship

The ideal alar-columellar relationship is 2–3 mm of columellar show in the lateral view.[50] Excess columellar show is associated with a hanging columella or a retracted ala.[50,51] The distance from the long axis of the nostril to either the alar rim or the columella roll should be 1–2 mm.[50,51] A longer distance to the superior half of the nostril is suggestive of alar retraction, whereas a decreased distance suggests a hanging ala.[50] Similarly, a longer distance to the inferior half suggests a hanging columella and a decreased distance represents columellar retraction.[50] Correction can be achieved by cephalocaudal repositioning of the ala, columella, or both.[50,51]

Periapical Hypoplasia

Volume deficiency in the central midface impacts nasal aesthetics.[52] A skeletal (maxillary) or soft tissue deficiency may produce periapical hypoplasia. Augmentation of the pyriform aperture can decrease the apparent size of the nose, increase the nasal tip and base projection, and widen the nasolabial angle.[52] This and other adjunctive procedures such as orthognathic surgery or malar augmentation may be considered along with rhinoplasty.[7] Furthermore, rhinoplasty can be a useful adjunct to restore the ideal nasomaxillofacial relationship following skeletal changes after orthognathic surgery.[53]

Lip-chin Relationship

Chin projecting surface should lie approximately at (preferred in men) or up to 3 mm posterior (in women) to a vertical line drawn from the half-distance point of the ideal nasal length and tangential to the upper lip vermillion anteriormost point.[54,55] Most rhinoplasty patients with chin disharmony have inadequate chin projection, either alone or in combination with inadequate chin vertical dimension.[54,56] A small chin may enlarge the apparent size of the nose and vice versa.[43,55,56]

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