Reconstruction of significant saddle nose deformity using autogenous costal cartilage graft with incorporated mirror image spreader grafts

Authors


INTRODUCTION

The classical term “saddle nose” is used to describe a number of nasal deformities of the lower two thirds of the nose resulting from loss of septal height and tip support. These deformities include underprojected cartilaginous dorsum, underprojected and over-rotated nasal tip, retracted columella, acute nasolabial angle, broad nasal tip, wide alar base, and an infratip:columella ratio of 1:1. Congenital causes are rare, but previous septoplasty or rhinoplasty, facial trauma, and septal abscess account for most saddle nose problems.1 Cocaine abuse and granulomatous disorders may result in the same type of deformities.1–3 From a practical point of view saddle nose deformities can be classified as minimal, moderate, and major.4 Minimal saddle nose deformities can be camouflaged using cartilage filler grafts. The majority of moderate deformities with reasonable septal support can be successfully treated with dorsal onlay grafts in combination with a columellar strut and tip graft shaped from the remaining septal and/or conchal cartilage. However, major saddle nose deformities, often devoid of septal cartilage, require significant structural restoration to resupport the lower two thirds of the nose. Conchal cartilage lacks both the strength and volume, in contrast to rib costal cartilage, which fulfils these requirements. Autogenous rib costal cartilage does rarely get infected or extrude.5 Moreover, resorption is less as compared to homologous irradiated rib cartilage grafts.6, 7 However, warping of the costal cartilage, whether autogenous or homologous in origin, is an established major problem that can lead to obvious postoperative deformities of the nose. We report a technique that may overcome the potential of warping when rib grafts are used to reconstruct the lower two thirds of the nose (major and moderate saddle nose deformity).

SURGICAL TECHNIQUE

The nasal cartilages and bones are skeletonized via a standard external rhinoplasty approach with particular attention to preserving the remaining septal mucosa. Only if insufficient septal cartilage remains, a graft is taken from the sixth rib with an incision length of 4 to 5 cm. The entire circumference of the cartilaginous rib may be dissected out from its perichondrial envelope. Alternatively, a strip of cartilage may be left inferiorly to maintain the continuity of the rib. The costal graft should have a length of at least 4 cm. The midportion of the costal cartilage is shaped as a neoseptum by carving the cartilage equally on each side. These outer slices will warp away from the central component by the nature of released interlocked stresses. Both outer aspects of the costal cartilage, which were shaved off as longitudinal strips, can now be sculptured symmetrically to form two spreader grafts.

The caudal end of the septal part of the reconstruction is secured onto the anterior nasal spine (ANS) by drilling two small burr holes tangentially through the ANS and one burr hole in the caudal protruding edge. A stable fixation of the neoseptum is created by suturing the neoseptum to the ANS using 3/0 Vicryl, which is passed through the burr holes. The inferior part of the neoseptum that will come to rest on the ANS, and the maxillary crest can be beveled so that the free caudal border will be positioned in between the medial crura at 120°. The more ventral part of the graft is used for medial crural support. In all cases, the septal graft extends caudally to be able to reproject the tip by fixing the medial crura to the septal graft in a tongue-in-groove fashion.

The longitudinal costal cartilage strips are placed in a mirror image fashion in between the septum and the separated upper lateral cartilages and suture-fixated to the costal cartilage neoseptum using 4/0 polidioxanone (PDS) mattress sutures. Using these warped costal cartilage strips in a mirror image fashion neutralizes their warping tendencies. The superior ends of the spreader grafts are attached on both sides of a remaining dorsal septal strut near to the keystone area. The spreader grafts are fixed in a position so that they project above the free edges of the collapsed alar cartilages aiming to give more height to the middle third of the nose. Caudally, the two spreader grafts slightly overlap the reconstructed neoseptum (Fig. 1). Thus, a strong laminated longitudinal midline structure results, providing strong midline support for the entire lower two thirds of the nose.

Figure 1.

(A) Composite structure of neoseptum and two mirror image spreader grafts. The exact size of the graft will be shaped when secured inside the nasal mucosal envelope and fixed to the remaining structures. The high spreader grafts will project above the upper lateral cartilages to correct the under projected middle third. (B) The warped spreader grafts are secured to the neoseptum in a mirror image fashion. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]

Subsequently, the dorsal aspect of the composite neoseptum + spreader grafts is aligned with a 27-g needle and secured with 4/0 PDS sutures to the upper lateral cartilages. The septal mucosa is secured to the neoseptum with 4/0 Vicryl Rapide (Ethicon, Somerville, NJ) mattress sutures. Any minor dorsal deformities are camouflaged with shaped and bruised cartilage grafts or soft tissue grafts, such as perichondrium or temporalis fascia. Further tip refinement is done as required at this stage. The incisions are closed and the neoseptum is supported with light nasal packs and an external nasal splint is applied. Figure 2 demonstrates the surgical outcome of this technique.

Figure 2.

Preoperative (A, B, and C) and 18-months postoperative views (D, E, and F) of patient with significant collapse of the lower two thirds of the nose with inadequate remaining septal cartilage. The under projection of the lower two thirds of the nose was corrected with autogenous costal cartilage graft with incorporated mirror image spreader grafts. Bruised extremely thin rib was placed in the nasofrontal angle and K areas. Supratip contour enhanced with perichondrial grafts taken from the concomitantly harvested conchal cartilage. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]

DISCUSSION

Depression of the lower two thirds of the nose is predominantly due to the loss of septal height and support.1, 2 Septal integrity is essentially dependent on a strong L-shaped dorsal and caudal cartilage strut with adequate attachments to the nasal bones and maxilla. Tip position is largely dependent on adequate support. Reconstruction of a major saddle nose deformity requires structural replacement—a common indication for rib grafting. This involves reconstruction of dorsal and caudal support structure with two articulated pieces of rib8 or a single unit costal cartilage graft.9 Alternatively, the rib graft can be used to create a stable midline septum.10 The main problem with rib costal cartilage used for dorsal augmentation is its tendency for warping.11–13 Hence, to address this problem principally, alternative osseocartilaginous grafts in various configurations have been described.14–17 Our technique involves reconstructing a stable midline extended septal structure that also provides support to the cartilaginous vault and addresses the problem of cartilage warping.

Although the complete pathogenesis of warping is not fully understood, inhibition of protein polysaccharide complexes appears to lead to reduction of interlocking stresses leading to warping.12 The technique of balanced cross-sectional carving of rib costal cartilage to minimize warping is well established.11 However, a curved rib cannot be modified into a straight dorsal or columellar graft without violating the principles set forth by Gibson and Davis.11 Allowing time for the initial warping to occur following harvesting of the cartilage before carving is another routine practice, as studies have shown that 90% of warping occurs within 60 minutes of harvesting13, 18; however, warping may continue over a 4-week period.18

Internal stabilization of rib cartilage with Kirschner wires to prevent warping has been described, but prevention of warping is not always guaranteed.19 The use of dorsal cartilage in a laminated fashion has been reported recently.20 This seems a good idea, but the laminated graft still needs asymmetric shaping to exactly conform to the dorsum.

In the technique that we describe, the neoseptum is reconstructed using the central part of the graft (to minimize warping effect) and has a stable fixation point to the ANS. The dorsum is reinforced with the mirror image costal cartilage spreader grafts. The moment these strips are shaved off from the central portion of the costal graft, the released interlocked stresses cause these strips to bend. The natural warping appearance is prevented by applying them in a mirror image fashion. The extended septal plate and spreader grafts interdigitate to produce a strong midline structure to which further rhinoplasty techniques can be applied. These spreader grafts also provide additional support in preventing collapse of the cartilaginous vault and indeed can address the concomitant collapsed nasal valve. The newly created strong middle third of the nose acts as a strong bar to counter rotate the often over-rotated tip, and the neoseptum does provide support for increased nasal projection. The tongue-in-groove technique helps recreate the nasal tip support mechanisms so that adequate tip position and shape can be achieved.

In our experience we have not had any exposure of the graft even when there is minimal septal cartilage present as careful and extensive dissection of the septal mucosal flaps is performed. If there is a concomitant septal perforation present, then careful and more extensive mucosal dissection onto the nasal floor and upstanding wall allows mobilization of the mucosal flaps and approximation of the perforation edges. In such cases the costal cartilage graft can act as an interposed scaffold as an aid in closure of the perforation.21

While using this technique in 14 patients, we have not had any incidences of postoperative deformity due to graft warping, resorption, visibility, or displacement. One must be aware that although the tendency might be to provide the best possible support, the neoseptum and the caudal attachments of the extended spreader grafts must be thinned down so as not to leave too much bulk in the caudal nasal septum and valve area. Our experience has reinforced the concept of harnessing the warping forces inherent to shaped rib grafts so as to produce a strong L-shaped midline support for saddle nose deformities.

Ancillary