Lobule, alar rim and nostrils — The lower third of the tip
Pinched infratip, discontinuous lobule and lobule-ala imbalance; unsupported rim, weak border and alar collapse; and why the nostrils are addressed last.
Content intended for healthcare professionals. It does not replace clinical assessment and is not written as patient information.
Key points
- The pinched infratip goes unnoticed unless sought: frontally it shows as an exaggerated distance between nostrils and the most caudal lobule, with a triangular shape.
- An unsupported rim and a weak alar border are not the same, though often confused: in the first the problem is border position; in the second, cartilage quality.
- Alar rim weakness is common in unoperated noses: described in around 20 % of primary rhinoplasties.
- On reducing projection, the nostrils widen and round out. Hence the base is addressed last, once the tip’s final shape is known.
- Base resection is limited to skin; mucosa is removed only when unavoidable and extremely conservatively.
Pinched infratip lobule
This alteration frequently goes unnoticed and deserves to be sought deliberately. On frontal view there is an exaggerated distance between the nostril level and the most caudal part of the lobule, with a characteristic triangular shape: as though the lower part of the tip lobule had been pinched. The mechanism lies in very long intermediate crura with a marked upward rotation angle, which verticalise the whole and leave the soft triangle unsupported, flaccid and close to the columella. Soft triangle collapse is therefore not an isolated finding but the visible consequence of intermediate crural geometry.
Discontinuous lobule and lobule-ala imbalance
The discontinuous lobule is a break in surface continuity presenting, according to severity, as bilobed, bifid or cleft. Correction scales with grade: from a crushed cartilage fill graft in mild cases, to a tip shaping graft or intradomal and interdomal sutures when the shape must be rebuilt. Lobule-ala imbalance is different: a disproportion between lobular projection and alar length that can reach absence of lobule. It is recognised in profile because the anterior end of the nostril finishes almost at the front of the nose, as if the lower portion of the lobule were missing.
Lobule-ala imbalance has three causes and a two-part solution
The disproportion may arise from very short or absent intermediate crura, a minimal or absent soft triangle, or lack of an infratip lobule — often all three at once. Correction is not only additive: one must increase projection with predomal grafts and simultaneously reduce the length of the columella or the alae. Acting on only one side of the imbalance leaves the problem half solved, because what is perceived is the relationship between the two, not the absolute measurement of either.
The alar rim: what holds it up
The alae extend laterally from the lobule to meet the face, and their caudal border — the alar rim — begins at the columella and describes a gentle arc. That arc is maintained by the support of the alar cartilages, to which the rim is firmly attached. When that attachment is weak, or the cartilage has a primary deformity, or is weakened after previous surgery, or is simply malpositioned — more posterior or more superior than it should be — the rim loses consistency: it separates from the cartilage or sinks at the lobule-to-ala transition. And what begins as a contour problem becomes functional, because it compromises the external valve.
The three grades of alar rim alteration
| Alteration | What is seen | Cause |
|---|---|---|
| Unsupported alar rim | Only the nostril border is retracted or below the caudal alar border: a linear shadow beneath the cartilage is seen | Alar malposition, congenital hypoplasia, or over-resection at a previous rhinoplasty |
| Alar rim weakness | The cartilage itself is flimsy: unsupported, rounded or flattened nostrils. Present in around 20 % of primary cases | Intrinsic cartilage quality, not its position. A primary finding, not a sequela |
| Alar collapse | The lateral wall collapses on forced inspiration. A serious functional alteration | Always implies severe damage to tip support. Primary from lateral wall weakness, or secondary — including chronic cocaine inhalation |
Telling position from quality changes the graft
The difference between an unsupported rim and border weakness is not academic: it determines which graft is needed. If the problem is positional — the border sits below a cartilage that is itself fine — an alar rim or contour graft suffices, sitting in a pocket just above the border and supporting it without needing fixation to the cartilage. If the problem is cartilage quality, that graft is not enough: the crus itself must be reinforced with a strut or onlay graft. And in established collapse a rigid graft may be required: ethmoid bone or costal cartilage. The ladder runs from supporting the border to replacing the structure.
The nostrils and the base
The nostrils are the openings formed between the alae and the columella, and constitute the external nasal valve. The columella is formed by the medial crura, usually straight, which diverge at the footplates and rest on the anterior nasal spine and caudal septum. All these alterations are studied on the basal view, and may be primary or sequelae of previous surgery. In the columella what usually fails is position and size; in the alae, an excessive arc giving dilated nostrils, deficient border consistency, or excessive thickness; and at the base, excess or thickening of the alae themselves.
Why the base is addressed last
Nostril treatment is the last step of the operation, for a concrete reason: reducing tip projection widens and rounds the nostrils. Deciding beforehand how much base to resect means deciding on an anatomy that will change during the surgery itself. Hence the correct sequence: finish the tip, assess how the nostrils have turned out, and only then measure. With two precautions: mark with callipers before infiltrating, since infiltration distorts, and limit resection to skin; if mucosa must be removed, do so extremely conservatively, because vestibular stenosis is far worse than a slightly large nostril.
Nasal base: what to resect and where
With the tip finished, is the excess at the alar base or at the nostril base?
References
- 1.Arquero P. Alteraciones nasales: lóbulo, borde alar y narinas. rinoplastia.eu.
- 2.Constantian MB. Four common anatomic variants that predispose to unfavorable rhinoplasty results: a study based on 150 consecutive secondary rhinoplasties. Plast Reconstr Surg. 2000;105(1):316-331.
- 3.Rohrich RJ, Raniere J Jr, Ha RY. The alar contour graft: correction and prevention of alar rim deformities in rhinoplasty. Plast Reconstr Surg. 2002;109(7):2495-2505.
- 4.Gunter JP, Friedman RM. Lateral crural strut graft: technique and clinical applications in rhinoplasty. Plast Reconstr Surg. 1997;99(4):943-952.
- 5.Daniel RK, Palhazi P. Rhinoplasty: An Anatomical and Clinical Atlas. Cham: Springer; 2018.
Related specialty: Rhinoplasty