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Chapter Basic Nasal Tip Surgery: Anatomy and Technique 325
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Anatomic variations of the lateral crural complex may have a direct impact on
tip support and rotation. To elaborate, the rigidity of the connection between
the lateral crus and accessory cartilages is directly related to the amount of tip
support provided and resistance to posterior movement of the nasal tip. Also, if
the abutment is high on the piriform aperture, there can be resistance to upward
tip rotation.
Medial Crural Attachments to the Caudal Septum
e medial crura of each lower lateral cartilage approximate one another in the
columella. Position, shape, and strength of the medial crura inuence tip support
and rotation. e medial crura approximate the caudal septum and anterior nasal
spine with broelastic tissue attachments providing support but allowing mobility. Posterior movement of the medial crura is possible to some extent, since the
caudal ends of each footplate ank the more midline septum and anterior nasal
spine. Disruption of these so tissue attachments, such as with a transxion incision, allows greater posterior displacement of the medial crura and decreased
tip projection. When the brous attachments from the medial crura to the caudal
septum are violated, the only support remaining is that of so tissue interposed
between the footplates and nasal spine. is tissue is compressible, and the support it supplies is solely dependent on its density. Medial crural length also inuences the support provided, because the closer the footplates are to the anterior
nasal spine and premaxilla, the less so tissue will be available for compression
and the greater the resistance to posterior movement.
In addition, ample so tissue, including collagen bers, adipocytes, and muscle
bers of the depressor septi nasi and orbicularis oris muscles, is found between
the opposing medial crura. Disruption of these so tissues during open rhinoplasty will also inuence tip projection.
Open rhinoplasty provides optimal exposure to the nasal framework. Such exposure allows comprehensive diagnosis and greater accuracy in surgical execution.
Suspensory Ligament of the Nasal Tip
Although some controversy exists regarding the nomenclature of the suspensory ligament of the nasal tip that is located in the interdomal region, its clinical relevance is not disputed. e ligament serves as a connection between the
cephalic margins of the lateral crura as they diverge in the supratip region. e
suspensory ligament rests over the anterior septal angle, in turn providing additional tip support. Clinically, when the dorsal septum is reduced or this ligament
is violated, support is reduced.
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Fibrous attachments of the lower lateral cartilages to the upper lateral cartilages,
piriform aperture, and caudal septum are responsible for nasal tip support and
position.
Surgical maneuvers including transxion incision, intercartilaginous incision,
cephalic trim, and lower lateral cartilage division will violate support structures
and change the position of these cartilages. Minor contributions to nasal tip support include the brous attachments of the lower lateral cartilages to the dorsal
septum, the membranous septum, and lower lateral cartilage attachments to the
overlying skin. e skin of the nose adheres to the tip cartilages, stabilizing the
tip and resisting movement of the tip cartilages. Freeing the skin from the cartilages eliminates this resistance. e overlying skin may play a more vital role in
tip support than previously thought.
THE TRIPOD CONCEPT
e tripod concept proposed by Anderson remains a useful means of understanding the relationship between tip rotation and projection.
upright, the tripod lies on its side, with one lower leg and two upper legs. e
lateral crura represent two upper lateral legs, and the abutting medial crura produce the central lower leg. e lower tripod leg is also inuenced by the caudal
septum. Shortening the medial crura or violating the related so tissue support,
as mentioned previously, leads to a decrease in nasal tip projection and rotation. Shortening of the upper legs or violation of associated so tissue leads to
decreased projection and increased rotation. Augmentation with gras or struts
that alter tripod leg length will also inuence tip position.
,
With the patient
Chapter Basic Nasal Tip Surgery: Anatomy and Technique 327
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Shortening (or violating support) of the lower leg leads to decreased projection
and rotation.
Shortening of the upper tripod legs will result in decreased projection and increased rotation.
Shortening of all three tripod legs will result in decreased projection, with minimal inuence on tip rotation.
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Lengthening the lower tripod leg should result in increased tip projection and
rotation.
Lengthening the upper tripod legs and shortening the lower leg should accentuate upward tip rotation.
e tripod concept facilitates an understanding of how surgical modications to
the medial and lateral crura inuence tip position.
Although the tripod concept provides a foundation for understanding surgery
of the nasal tip, it is apparent that subtleties in tip dynamics preclude total reliability. e tripod concept provides a basis for diagnosing abnormalities and
guiding surgical planning.
MODIFICATIONS OF THE TIP CARTILAGES
Modied tip cartilages are commonly used for the following purposes:
1. To alter tip projection
2. To alter tip rotation
3. To improve tip denition
4. To reduce tip fullness
5. To create a supratip break
6. To improve the alar-columellar relationship
Chapter Basic Nasal Tip Surgery: Anatomy and Technique 329
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Many techniques to achieve such goals have been described, including the following:
■
Cephalic trim of the lateral crura
■
Suture reshaping of the cartilages
■
Suture repositioning of the cartilages
■
Vertical transection and overlapping of the lateral crura
■
Vertical transection and overlapping of the medial crura
■
Excision of the medial crura caudal margins
■
Resection of the caudal septum
■
Placement of tip gra(s)
■
Placement of a columellar strut gra
■
Placement of lateral crural strut gras
■
Placement of alar spreader gra(s)
■
Placement of extended alar contour gra(s)
Altering Tip Projection
Increasing Tip Projection
Increasing projection of the nasal tip can prove quite challenging.
-
When there is moderate aring of the medial crura as they transcend the dome
area, suturing the medial aspect of the domes together can provide a slight increase in tip projection. us suturing straightens the are of the anterior medial
and middle crura.
Suturing ared medial crura together provides a small increase in nasal tip projection.
Placement of a columellar strut gra may provide some increase in
is is particularly true when using a xed
-
acteristics. If the columellar strut is insucient to expand the nasal
tip or the skin envelope restricts projection, there will be little or no
ment helps to maintain tip projection and is used to unify the tip to
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nasal tip projection.
,-
strut and less so when using a oating strut. e increase in projec
tion is relative to strut size and is inuenced by skin envelope char
increase in tip movement. In this case, columellar strut gra place
allow tip reshaping.
e amount of tip projection achieved with columellar strut gra placement also
varies depending on the surgical approach. With the closed approach, a minimal
increase in tip projection can be accomplished. In a closed approach the strut is
placed through a vertical incision at the base of the columella. A pocket is created between the medial crura to the level of the anterior nasal spine. A so tissue
interface is preserved on the anterior nasal spine to prevent direct abutment of
the strut on the ridge inferior to the anterior nasal spine. Contact at this area can
lead to clicking or lateral displacement of the strut. Placement of the columellar
strut gra into the pocket is accomplished by passing it through the vertical incision while using a double-pronged skin hook secured in each vestibular apex
to maintain the tip in the desired position. Use of a Brown-Adson forceps allows
pushing the strut rst toward the pocket base and then into its anterior position.
Pocket size should extend to mm beyond the anterior end of the incision to
allow projection of the strut past the incision edge.
Chapter Basic Nasal Tip Surgery: Anatomy and Technique 331
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Columellar strut placement using an open approach allows a greater increase in
tip projection, given the ability to release the lower lateral cartilages and reestablish them in a more projecting position on the strut. Following elevation of
the nasal skin envelope, a pocket is created between the feet of the medial crura.
Again, a so tissue layer is preserved on the premaxilla to avoid having the strut
seated directly on nasal spine bone. e columellar strut can be placed in an invisible position by dissecting the pocket closer to the caudal septum superiorly. If
changes in the shape of the columella, alteration of the alar-columellar relationship, and/or columellar-labial transition are desired, this pocket can be dissected
closer to the columellar skin.
If changes in the shape of the columella, alteration of the alar-columellar relationship, and/or columellar-labial transition are desired, this pocket can be dissected closer to the columellar skin.
e columellar strut is placed into the pocket with Brown-Adson forceps and
pushed toward the anterior nasal spine to ensure that it is resting in the bottom
of the pocket. Double-pronged skin hooks secured in each vestibular apex are
used to maintain the tip in the desired position during placement of the medial
crural−columellar strut sutures. A -gauge needle can be used to align the strut
during suturing by placing it through the medial crus and columellar strut, then
through the opposite medial crus.
Open approach placement of a columellar strut provides superior control and a
greater increase in tip projection.
If additional projection is needed, a shield-shaped tip gra is used. e
original Sheen description used a at shield-shaped gra from septal
e blunted cartilage
remained to mm apart to create the two tip-dening points. Gra
length varied, depending on the projection needed, but on average
was to mm. Gra placement using the closed approach occurred
through an infracartilaginous incision extending along the caudal rim
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When additional strength and rigidity are needed for the columellar strut gra,
a mm wide and mm long piece of harvested septal cartilage is required. A
midline longitudinal partial-thickness incision is created on one side of the cartilage. e cartilage is then folded on itself toward the intact side. e cartilage will
bend and break, but the intact surface serves as a hinge keeping the two pieces
together. is makes the strut easier to handle and obviates the need to suture
the two pieces together. However, this two-layered columellar strut may result
in an excessively wide columella.
If additional tip projection is required, the lateral crura may be advanced medially. is maneuver is termed the lateral crural steal and is performed with
horizontal mattress sutures, resulting in the creation of new tip-dening points
on each lateral crus. Suture placement is performed so that the medial vertical
segment of the suture lies on the same vertical plane as the original tip-dening
point. e lateral vertical segment of the suture then lies to mm lateral to
the tip-dening point. e suture knot lies medially. Adson-Brown forceps are
used to crimp the cartilage halfway between the vertical suture segments. e
suture is tightened and tied to secure the position of the manipulated cartilage.
Suturing of the medial surfaces to the columellar strut stabilizes the tip. Finally,
the anteriormost aspect of the columellar strut is cut ush with the tip-dening
points. Lateral crural steal is easier when the convexity of the domes is a gentle
curve and is not more acutely angulated.
Lateral crural steal involves advancing the lateral crura medially and using horizontal mattress sutures to create new tip-dening points on each lateral crus.
cartilage with one end notched in the center.
of the medial crura to the anterior columella.
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Chapter Basic Nasal Tip Surgery: Anatomy and Technique 333
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Placement of the shield gra through the open approach was popularized by
Johnson and Wyatt and allowed a more accurate xation. e degree of tip projection required determines gra thickness and possible placement of multiple
stacked gras.
Over time the tip gra can become visible, with thinning of the overlying skin,
distortion of the gra, or displacement of the gra. Visibility is primarily a problem when gra edges are appreciated through the skin. To circumvent such outcomes, using blended tip gras such as anatomic cap gras from the cartilage
removed during cephalic trim or morselized septal cartilage can alter tip shape
while having imperceptible edges. Additionally, meticulous carving of the gra
edges is important. Also, using cartilage pieces or additional gras in a stacking
manner to obviate dead space behind the gra will create a more camouaged
tip if the skin thins.
A graduated approach to increasing tip projection includes placement of a columellar strut gra, followed by lateral crural steal with xation to the strut, and
if necessary, tip graing may also be used to achieve greater tip projection.
Septal extension gras may also be used to increase tip projection.
,
Various
types of septal extension gras exist (see Chapter ).
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When the increase in tip projection exceeds mm, autologous rib is used for
strut fabrication. Rib cartilage is inherently rigid and can be harvested to any re
quired length. Initially, columellar struts were carved with a notch on one end.
is end was then placed so that the notch seated directly on the anterior nasal
spine. Tip projection of to mm could be gained with this method, but the strut
placed in this plane led to signicant widening of the columella and was subject to warping forces. Evolution of the technique led to the use of a .-inch
threaded K-wire placed through the strut with one end xed to the premaxilla.
Although use of the K-wire evaded warping, it was not without complications.
Some authors reported that wires became infected and/or suered extrusion. Because of these problems, K-wires are not commonly used in the columella today.
-
Carving balanced cross-sections of cartilage should be practiced when creating
struts from rib cartilage to minimize warping. Furthermore, these long columellar struts can be used with extended spreader gras for additional support and tip
projection. Problems with the use of large columellar strut gras include excessive widening of the columella and limited mobility of the nasal tip. Such factors
must be considered when using a columellar strut gra.
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