Evidence-Based Nasal Analysis for Rhinoplasty

The 10-7-5 Method

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


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

In This Article

Basal View (5 Key Areas)

Nasal Projection

On basal view, the nose should create an equilateral triangle with a columella-to-lobule ratio of 2:1.[7,8,57] Nasal tip refinement, using both suture modification of existing cartilage and soft cartilage grafts instead of rigid visible grafts, has been recommended for correction of poorly defined tip-defining points and nasal over or under-projection.[57]


The nostrils should be symmetric and have a teardrop shape with a long axis extending from the base to apex.[7,8] The ideal nostril-tip relationship should be ~2:1.[43] A relationship imbalance can result in a long and narrow nostril, or inversely in a short and wide one. In ideal basal view, the alar rims fall within an equilateral triangle.[29,58] A concave ala may result in alar collapse or a pinched tip secondary to weak lateral crura, which is often a consequence of inappropriate interruption or excessive resection of the lower lateral cartilage, improper tip graft placement extending laterally to existing dome, or a transdomal suture too tight.[29,58] A convex ala is usually caused by an excessive convexity of the lower lateral cartilage or alar thickness.[58]


The ideal columella requires a smooth concave shape bridging the nasal tip and nasolabial junction.[59] Columella primary (intrinsic) deformities originate from malpositioned medial crura or excessive soft tissue.[59] Most commonly, a widened or asymmetric columella results from premature or excessive medial crura flaring.[59] Secondary deformities are often the result of caudal septum deviation, pushing the medial crura and soft tissue into the nostril.[59]

Alar Base and Alar Flaring

Proper assessment of nasal base width requires a clear distinction between the width of the alar base and the degree of alar flare. Ideal nasal width approximates the intercanthal distance (normal, 31–33 mm).[31,60] Alar flare is defined as the greatest width of the ala, which convexity should not exceed 2–3 mm lateral to the alar-facial crease.[30,31] Three types of alar flare were described.[3,31] Flare was classified according to where the most lateral point along the alar rim occurs relative to the level of the sill-base junction on basal view (below, at, or above this level).[31] Alar base wedge excision is designed to address alar flare only.[3,31] Correction of other horizontal alar base disharmonies may require wedge excision of the nostril sill, narrowing the base laterally, reduction of the alar base thickness, or a combination of these techniques.[60]