IV. CLINICAL APPLICATION OF CARTILAGE GRAFTS IN FACIAL PLASTIC SURGERY

Cartilage autografts have been utilized to augment various areas of the face. By far, the most common site for cartilage grafting is in nasal reconstruction. The present trend in nasal contouring is to produce a natural sculptured appearance. This has greatly increased the utilization of cartilage grafts. These grafts are used to augment, contour, and support the nasal structure. Each application produces specific effects. Familiarity with the nature of the grafts and the effect of their clinical application is necessary if the surgeon wishes to make full use of these wonderfully accessible and inexpensive materials.

A) DORSAL AUGMENTATION

Lack of projection of the nasal dorsum can occur as a congenital abnormality, a racial characteristic, and secondary to trauma or prior surgery. The use of cartilage autografts to correct this problem is a safe, reliable, and permanent method of correction. Grafts augmenting the nasal dorsum may he inserted through an endonasal or external approach. The advantage of the external approach to placement of these grafts is accuracy in positioning and suture fixation of the grafts. Septal cartilage is most frequently used as a single or multiple layered graft (Figure 3A to F).

FIGURE 3C to F

When septal cartilage is not available, auricular cartilage or rib may be used. Although auricular cartilage is curved, some relatively straight segments can he obtained and sutured together with 5.0 Nylon. This layered graft can he carved to the appropriate size and shape and the edges can he beveled with a knife or an abrasive (Figure 4A and B).

FIGURE 4. Preparation of double-layered cartilage autograft for dorsal augmentation. (A) Side view; (H) top view illustrating position of sutures.

B. NASAL CONTOUR DEFECTS

Small nasal contour defects can he corrected utilizing appropriate sized grafts taken from the nasal septum or the concha of the ear. These can be inserted endonasally into small exactly placed pockets or through an external approach, in which case the grafts are sutured into the proper position and retained permanently (Figure 5A to C).

FIGURE 5. Correction of alar defects with contour grafts. (A) Illustration of placement of graft over deficient alar cartilages; (B) photograph of alar cartilage defect exposed through the external approach; (C) conchal cartilage autograft (arrow) sutured in place to recontour alar.

The curved conchal cartilage conforms to the nasal contour. When straight septal cartilage is used, light morsalization or scoring may be needed to soften and increase its flexibility. This is particularly true when dealing with alar deformities. In addition to correcting asymmetries or irregularities of the nasal base, these grafts can he inserted anywhere along the nasal dorsum to correct filling defects (Figures 6 and 7).

FIGURE 6. Correction of defect of region of upper lateral cartilage. (A) Illustration of graft placement which may be lateral or medial to upper lateral cartilage; (B) photograph of graft placement.

FIGURE 7. Example of use of cartilage autograft to correct contour defects of alar and lateral nasal regions. Photographs of: (A) Frontal and (C) lateral preoperative views of patient with marked deficits of alar and lateral nasal regions: (B) frontal and (D) lateral views 3 years after correction, utilizing septal cartilage autografts to recontour nose as described in text.

When there is excessive narrowing of one or both sides of the nose, a cartilage strip (spreader graft) can be inserted medial to the nasal bones and/or the upper lateral cartilage. This will position the hone or upper lateral cartilage laterally. A piece of cartilage can also be contoured and layered on the outside of the bone to fill in the defect.

C. NASAL BASE GRAFTING

The nasal base is the most frequent site for cartilage grafts in the nose. The grafts inserted in the nasal base assist in tip projection, rotation, and contouring, particularly of the columella and the nasolabial angle. The various positions of nasal base grafts produce specific sup-porting and contouring effects which are discussed below. The columella strut, as originally advocated by Anderson, was inserted through a vertical incision at the inner margin of the columella. A pocket is created intercrurally from the premaxilla to the top of the columella without entering the lobule (Figure 5A and B).

FIGURE I. A and B. Septal cartilage autograft accessed through the external approach. (A) Septal cartilage incision leaving adequate anterior and dorsal supporting segments; (B) removal of a large septal cartilage autograft through external approach.

	FIGURE 9. Illustration of columella strut augmenting the length of the medial crura.

The strut is rectangular and usually tapered at each end for ease of insertion into the intercrural pocket (Figure IC). It extends down to the premaxilla, so that it is situated on a firm base, thus supporting the lobule. This same intercrural columella strut can be inserted through an external approach which is now Anderson's preferred route and achieves the same effect. An intercrurally inserted columella strut supports or increases tip projection by maintaining or elongating the columella length (Figure 9).

As it increases tip projection, it rotates the lobule in a cephalic direction reducing the nasal length. This effect on the lobule also produces an angulation or curvature at the columella lobule junction. It produces little effect on the nasolabial angle (Figure 10A and B).

	FIGURE 10. Clinical example of the effects of an intercrural columella strut placed through an external approach. (A) Preoperative lateral view; (B) 2-year postoperative lateral view. Note the elongation of the columella which projects and rotates the lobule. Tip definition improves and an angle is created at the columella-lobule junction.
FIGURE 11. Photographs of IA) twisted medial crura exposed through the external approach; B) columella strut sutured between medial crura straightening and sup-porting them.

It will also correct a distorted columella (Figure 11 A and 13).

	FIGURE 13. Use of graft confined to lobule. (A) Illustration of ideal placement of lobule graft. Photographs of BI preoperative view of under-projected and poorly defined tip; (C) I year after correction with tip graft increasing tip projection and definition.

A columella supporting and contouring graft may also be placed in a precrural position. From a similar lateral columella incision, rather than inserting the graft between the medial crura, the graft is inserted anterior to the medial crura. This places the graft directly beneath the skin of the columella. The length of the graft should extend from the premaxilla up to the columella lobule junction, without entering the lobule. This produces the same effect on tip projection and lobule rotation as when placed intercrurally. In addition, it adds a If extended too far inferiorly (into the columella), projection will also be lost and the inferior point of the graft will he visible on the columella. The purpose of the shield graft is to project and improve tip definition. Ideally, it elongates and narrows the lobule and defines the end point of the tip. It will appear to rotate the tip in a cephalic direction and produce an angulation at the columella-lobule junction. It does not change the columella or the nasolabial angle (Figure 13A to C).

It is actually replacing and not altering the structural components of the lobule. Accurate placement of this graft through the endonasal approach is difficult. In this author's experience, graft shifting and tip asymmetries occurred in a great many cases. This problem can be eliminated by the external approach. This exposure allows proper placement and suture fixation of the graft. Suture fixation of the short tip graft confined to the area of the lobule is very time consuming.

	FIGURE 14. Precrural columella-lobule graft (versatile tip re-placement graft). Illustration of position of graft which can effectively replace the columella and lobule cartilage components creating a new tip.

A much simpler technique for achieving increased tip projection and narrowing, utilizes a longer graft inserted through the external approach, extending the length of the lobule and the columella. It is placed anterior to the columella. Inferiorly, a pocket created in front of the feet of the medial crura accepts the tapered bottom portion of the graft. Superiorly, the graft extends above the existing height of the alar cartilage creating a new tip defining point.

If extended too far inferiorly (into the columella), projection will also be lost and the inferior point of the graft will he visible on the columella. The purpose of the shield graft is to project and improve tip definition. Ideally, it elongates and narrows the lobule and defines the end point of the tip. It will appear to rotate the tip in a cephalic direction and produce an angulation at the columella-lobule junction. It does not change the columella or the nasolabial angle (Figure 13A to C).

It is actually replacing and not altering the structural components of the lobule. Accurate placement of this graft through the endonasal approach is difficult. In this author's experience, graft shifting and tip asymmetries occurred in a great many cases. This problem can be eliminated by the external approach. This exposure allows proper placement and suture fixation of the graft. Suture fixation of the short tip graft confined to the area of the lobule is very time consuming.

	FIGURE 15. Placement of columella-lobule graft. Photographs of (A) tip position prior to graft placement after an external incision has been made; (B) base view of positioning of graft; (C) lateral view of graft sutured in place projecting above the dorsal nasal line; II)) skin repositioned and graft in place. Notice increased tip projection as compared to (A).

Superiorly, the graft extends above the existing height of the alar cartilage creating a new tip defining point (Figure 14).

The graft can be moved in a vertical direction to increase or decrease desired tip projection. Once placed in the inferior pocket, it is relatively easy to place a suture through the medial crura and then tie this suture in front of the graft. The graft is thus firmly fixed in position. The superior portion can then be further trimmed if desired (Figure 15A to D).

The graft is ideally made from a segment of septum which has some flexibility so that there will be a curve to the columella lobule complex. Auricular cartilage may be used when septa] cartilage is not available. As tip projection is increased with this graft, there is a tendency towards cephalic rotation. This occurs because there is a limit to the degree of stretch in the skin of the columella and the lobule. Tip blunting, which can occur with a shield graft, will not happen with this graft. Once this graft is in place and positioned, redraping of the skin will show the exact placement and position of the new tip. Because of the firm fixation, this will not tend to change postoperatively (Figure 16A to C).

	FIGURE 16. Clinical effect of precrural columella lobule grail. Photographs of (A) preoperative view short columella and weak lobule structure; (B) I-year postoperative insertion of columella-lobule graft with resultant increase in columella and lobule length and improved tip projection, definition, and cephalic rotation.
		FIGURE - 16C The same patient 17 years postoperative. Clinical effect is maintained.
	FIGURE 17. Use of columella-lobule graft to correct tip ptosis. Photographs of IA) postoperative tip ptosis with almost complete absence of tip-supporting structure; B) 2-year postoperative replacement of absent tip structure with columella-lobule septal cartilage autograft.

This graft allows the surgeon to accurately create a new tip contour without depending on the patient's own structural components. It is an important concept for surgical correction of difficult tips of any variety. This includes amorphous or thick-skinned tips in both caucasian and noncaucasian patients. It is invaluable in revision surgery, particularly when there is very little alar cartilage left. It can effectively substitute for an entirely absent tip structure (Figure I 7A and B).

It will also correct asymmetries in the lobule by replacing the existing asymmetric components.

The use of onlay grafts to augment the lobule and increase tip projection produces no change in the columella lobular profile line. A single- or double-layered cartilage graft taken from the septum or concha can be placed above the existing domes. This will increase the height of the nasal tip. These can be inserted through an endonasal or external approach.

The external approach is a more accurate method of positioning this as well as any other type of graft. In addition, one can combine this with an intercrural columella strut. This produces a T-shaped graft and serves to fix the position of the underlying support for the onlay graft.

D. PREMAXILLARY GRAFTS

Although the premaxilla is not part of the nose, it is the foundation for nasal tip projection. It forms part of the nasolabial angle which is important in nasal aesthetics. Deficiencies of the premaxillary region contribute to an acute nasolabial angle and a retracted upper lip.

Premaxillary deficiency may also contribute to poor columella-tip support resulting in a depressed tip. The premaxilla can be augmented by various means. In the past, multiple small bits of cartilage and/or bone taken from areas removed during rhinoplasty were placed in the premaxilla through an incision in the floor of the nasal vestibule. These produced very little change. In order to produce an appropriate effect, larger grafts are necessary. Conchal cartilage, either layered or rolled, layers of septal cartilage sutured together, and solid segments of rib cartilage are excellent grafts. These grafts can be inserted through the floor of the nasal vestibule or through a sublabial incision (Figure 18A and B).

The premaxilla acts more like the rest of the face than the nose as a recipient site for grafting material. Therefore, silastic or other alloplasts can be utilized for premaxillary augmentation without the same fears one encounters in the nose.

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