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15
Dorsal Augmentation: Onlay Graing
Using Shaped Autologous Septal Cartilage
C. Spencer Cochran Jack P. Gunter Rod J. Rohrich
Autologous septal cartilage dorsal onlay gras are appropriate in primary and
secondary rhinoplasty patients in whom a minimal to moderate amount of dorsal augmentation is desired. Depending on the degree of augmentation required,
gras can be single layered or multilayered in the form of a V-frame, A-frame,
or U-frame gra. e dorsal elevation is thus tailored to t the imperfection at
hand, resulting in a smooth, natural-looking nasal contour. e indications for
each type of gra will be reviewed and the surgical technique described.
Autologous septal cartilage dorsal onlay gras are appropriate in primary and
secondary rhinoplasty patients in whom a minimal to moderate amount of dorsal augmentation is desired.
BACKGROUND
As the aesthetic evaluation of the nose has become more sophisticated, the need
for dorsal augmentation in rhinoplasty has become increasingly apparent.
the past, surgeons performing augmentation rhinoplasty were largely frustrated
in their attempts to attain a natural-looking nasal dorsum using onlay gras.
Synthetic materials seem to give satisfactory results but have not been universally accepted because of the ever-present dangers of exposure and infection.
Irradiated homologous rib cartilage has been used successfully, but problems
with warping, absorption, and infection limit its application in the nose. Autologous costal, iliac, and cranial bones have all been used to augment the nasal
Chapter adapted from Gunter JP, Rohrich RJ. Augmentation rhinoplasty: dorsal onlay graing using
shaped autogenous septal cartilage. Plast Reconstr Surg :-, .
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In
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275
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dorsum.
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Unfortunately, bone onlay gras are dicult to shape and oen undergo an unpredictable degree of absorption by the surrounding tissues. ese
sources are therefore reserved for the more severe nasal deformities when other
gra materials are deemed unsatisfactory.
Recently there has been considerable interest in the role of diced cartilage gras
for dorsal augmentation (see Chapter ), but controversy exists as to the longterm viability of the diced cartilage and the predictability of molding it into
the desired shape.
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Although diced cartilage may represent a viable means of
contour restoration, at present structural graing and moderate to large dorsal
augmentations are better corrected with a more substantial graing alternative.
Autologous rib cartilage, on the other hand, is easily carved and rarely resorbs,
but it does have a tendency to warp and must be obtained from a distant donor
,
site.
Similarly, autologous auricular cartilage must be harvested through a
separate incision, and its peculiar contour renders it dicult to carve into the
desired shape. Although the initial contour of the augmented dorsum may be
good when auricular cartilage is used, surface irregularities oen become apparent with the passage of time.
Autologous septal cartilage can be harvested from the same operative eld with
little increase in morbidity and is the tissue of choice for nasal augmentation if
it can be shaped into the desired contour. When autologous septal cartilage is
available, we have used it as a gra source for primary and secondary rhinoplasty
patients requiring minimal to moderate dorsal augmentation.
INDICATIONS AND CONTRAINDICATIONS
e aesthetics of the nasal dorsum and the patient’s preferences and goals must
be considered to determine whether dorsal augmentation is necessary.
Dorsal onlay graing is indicated in patients with a low nasofrontal angle, diminished dorsal height or an excessive concavity of the dorsal prole on lateral view.
Dorsal augmentation to widen the dorsum should also be considered in short
nasal bone syndrome, as dened by Sheen and Sheen. is condition is said
to be present when the bony pyramid is less than one third the distance from
the nasofrontal angle to the septal angle. It is accompanied by a narrow upper
vault and bilateral concavities of the cartilaginous vault. Sheen recommended
spreader gras to support the middle vault area, but if the nasal valves are not
compromised, an alternative to spreader gras is a dorsal onlay gra to widen
the dorsum and improve the aesthetic results.
Chapter Dorsal Augmentation: Onlay Graing Using Shaped Autologous Septal Cartilage 277
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Although there are no absolute contraindications to dorsal augmentation, it
should be performed with caution in thin-skinned patients, because the edges
of the dorsal onlay gra may become visible as a step-o or ridge over time as
the so tissue envelope contracts.
PREOPERATIVE ASSESSMENT AND PLANNING
A key component of operative planning in rhinoplasty includes assessment of
the overall graing requirements and determination of the potential source of
graing materials that will be required. Patients in whom there is little septal
cartilage available or in whom multiple gras will be required in other areas of
the nose may require alternative sources of graing material.
Analysis begins with the lateral view of the patient’s preoperative photograph to
determine the position of the nasofrontal angle. In white patients, the nasofrontal angle should lie between the superior lash line and the supratarsal crease on
lateral view. In Asian and black patients, the nasofrontal angle should lie between
the midpupillary line and the superior lash line. If the nasofrontal angle is below
these levels, nasal-dorsal augmentation to raise the position of the angle should
be considered. Ideally, men have a higher nasal bridge than women, and the criteria for dorsal augmentation are adjusted accordingly.
On the prole view in women, the dorsum should lie parallel and approximately
mm posterior to a straight line drawn from just above the nasofrontal angle
to the tip-dening points, if the tip projection is normal. If a distance of more
than mm separates the nasal dorsum and this line or if the dorsum appears
overly concave, dorsal augmentation should be considered. If the tip projection
requires an increase or decrease, this should be factored into the evaluation of
dorsal height.
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On the frontal view, the nasal dorsum should be outlined by two slightly curved,
divergent lines that extend from the medial supraciliary ridges to the tip-dening
points. ese are the dorsal aesthetic lines. e dorsum should be of sucient
height to create a distinct anatomic separation of the eyes and give a third dimension to that portion of the face.
OPERATIVE TECHNIQUE
e septal cartilage is harvested through a standard septoplasty approach. Aer
the desired length and width of the onlay gra are determined, the cartilage is
cut into an oval or fusiform shape, and any irregularities of the surfaces resulting from dierences in thickness are shaved. e edges of the gra should be
beveled at approximately a -degree angle to avoid the appearance of a step-o
postoperatively.
e edges of the gra should be beveled at approximately a 45-degree angle to
avoid the appearance of a step-o postoperatively.
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To aid in the dorsal onlay gra conforming to the contour of the dorsum, a
partial-thickness longitudinal incision can be made on the surface of the gra.
Digital pressure is applied along the incision until a greenstick fracture occurs.
DORSAL ONLAY GRAFTS
A-frameInverted U-frameInverted V-frame
is results in the cartilage assuming an upside-down V conguration. Alternatively, two or three partial-thickness incisions can be made to form a U-frame
gra, or a piece of cartilage can be placed under a V-frame gra to form an
A-frame gra. Since they are only one layer thick, however, their application is
limited to patients requiring minimal augmentation.
e V-frame and U-frame gras t better over the arched contour of the dorsum
and are more stable than a at piece of septal cartilage.
For patients who require more nasal dorsal augmentation, a second layer of cartilage can be placed on the undersurface of the original dorsal onlay gra. If
more augmentation is needed at one end of the gra than the other, short strips
of cartilage are placed under that end only. is procedure can be used in primary as well as secondary rhinoplasty patients.
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Alternatively, one or more crossbars of cartilage can be placed under the V-frame
gra between the arms of the V and be suture-stabilized to them, resulting in
an A-frame gra. is increases the amount of dorsal augmentation that can
be obtained, and if needed, the degree of angulation of the vertical limbs of the
A-frame gra can be controlled by varying the width of the cartilage crossbar.
is technique has proved useful in patients with a moderately low nasal dorsum,
as is oen seen aer overzealous rhinoplasty.
Once the dorsal onlay gra has been fabricated, the gra is placed beneath the
so tissue envelope to conrm the desired amount of augmentation. e gra
should be stabilized to the osteocartilaginous framework to prevent it from shiing. Superiorly the gra can be xated with a temporary .inch K-wire placed
percutaneously through the gra and nasal bones; to mm of the temporary
K-wire is le exposed above the dorsal skin and is easily removed with a wire
twister aer week. Inferiorly, the gra should be suture-xed to the cartilaginous dorsum.
CASE ANALYSES
is Asian patient presented for primary rhinoplasty. She desired dorsal augmentation and tip renement.
e operative goals included the following:
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Rene the tip.
■
Augment the dorsum by mm.
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Reposition the radix more superiorly.
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Surgical Plan
1. Use an open approach with a stair-step transcolumellar incision and bilateral
infracartilaginous extensions.
2. Harvest septal cartilage.
3. Augment the dorsum with a double-layered U-frame dorsal onlay gra.
4. Perform a cephalic trim of the lower lateral crura leaving a mm alar rim
strip.
5. Place a columellar strut gra with medial crural−columellar strut sutures.
6. Place alar contour gras.
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e patient is shown months postoperatively. On frontal view, the improvement of her dorsal aesthetic lines is evident. e prole view shows the repositioning of her nasofrontal angle from the lower lash line to the superior lash line
and dorsal augmentation.
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is primary rhinoplasty patient desired minimal dorsal augmentation and tip
renement.
e operative goals included the following:
■
Rene the tip.
■
Create a more balanced dorsum with augmentation of the upper two
thirds.
■
Reposition the radix more superiorly.
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Inverted-V-frame
Surgical Plan
1. Use an open approach with a stair-step transcolumellar incision and bilateral
infracartilaginous extensions.
2. Reduce the lower third of the dorsum.
3. Augment the upper two thirds of the dorsum using an inverted-V-frame gra.
4. Perform a cephalic trim of the lateral crura leaving a mm alar rim strip.
5. Place a columellar strut gra with medial crural−columellar strut sutures.
6. Rene the tip with transdomal sutures.
7. Perform lateral osteotomies.
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