The incidence of postoperative nasal deformities requiring secondary rhinoplasty varies from 5% to 12%. The etiologies of postoperative nasal deformities ( Table 7-1 ) are usually related to one or any combination of the following three problems: (1) displacement or distortion of anatomic structures, (2) underresection due to incomplete surgery, and (3) overresection due to overzealous surgery. Diagnosing these deformities and reconstructing the nasal osseocartilagenous framework form the foundation for obtaining consistent functional and aesthetic results in secondary rhinoplasty.
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While adequate results may be attained with the endonasal technique in certain circumstances, the limited dissection and exposure offered by the endonasal approach often do not permit accurate assessment, intraoperative diagnosis, and appropriate treatment of complex anatomic problems. Open rhinoplasty techniques eliminate these restrictions imposed by the endonasal approach. We present a systematic approach to secondary rhinoplasty via the external approach that helps ensure consistent aesthetic and functional results in patients with both major and minor postoperative nasal deformities.
Preoperative Assessment and Planning
A precise anatomic diagnosis is a key step to achieving optimal results in secondary rhinoplasty. The preoperative evaluation begins by defining the deformity, which is accomplished by a detailed history, physical examination, and complete aesthetic facial and nasal analysis. Starting superiorly, the nasofrontal angle height and depth are noted. The bony pyramid, upper lateral cartilages, and supratip are evaluated for their length, height, width, and symmetry. The nasal tip is evaluated in terms of its projection, rotation, symmetry, and position of the tip-defining points. The alae are inspected for increased width, collapse, or retraction. The columella is examined for increased or decreased show. The columellar-lobular and columellar-labial angles are evaluated to ascertain the desired angulation. The internal nasal examination evaluates patency of the nasal valves, position and integrity of the septum, and state of the turbinates.
After the diagnosis is determined and the deformities are defined, the goals of the surgery are established, and a treatment plan is formulated. The operative goals are individualized for each patient according to the deformity. The goals may be to augment the nasofrontal angle, straighten the nasal dorsum, lower the supratip area, correct tip asymmetry and alar collapse, decrease columellar show, etc. If the existing osseocartilagenous framework is underresected, the amount and location of further reduction are determined. If the nasal framework has been overresected, it is determined what tissues are missing and where augmentation is needed. Secondary surgery is usually deferred until 12 months after the previous rhinoplasty.
Grafting Alternatives
A key component of the operative planning includes assessment of the grafting requirements and the potential source of grafting materials that will be required. While septal cartilage is generally the preferred grafting material in both primary and secondary rhinoplasty, severe deformities or a paucity of available septal cartilage requires an alternative source of grafting material. This is particularly true in secondary rhinoplasty when structural deformities resulting from previous procedures necessitate significant numbers of grafts. Autogenous cartilage is preferred for any nasal framework replacement.
Septal Cartilage
There are several advantages to using septal cartilage. A large amount of septal cartilage and septal bone can be harvested from the same operative field without the morbidity of an additional donor site. Compared to auricular cartilage, septal cartilage is more rigid, provides better support, and does not have convolutions. It is preferably used as a columellar strut, spreader grafts between the upper lateral cartilages and the septum, and lateral crural strut grafts to support or replace parts of the lower lateral cartilage complexes. When a sufficient quantity is available, it may also be used as a dorsal onlay graft for minimal amounts of dorsal augmentation.
Auricular Cartilage
The auricle can provide a modest amount of cartilage for nasal reconstruction. Using a postauricular approach, the amount of harvested conchal cartilage can be maximized without compromising ear protrusion by preserving sufficient cartilage in three key areas: (1) the inferior crus of the antihelix, (2) the root of the helix, and (3) the area where the concha cavum transitions into the posterior-inferior margin of the external auditory canal. An incision is created longitudinally along the posterior aspect of the auricle, and dissection is carried down through the perichondrium. A 27-gauge needle dipped in methylene blue is percutaneously placed every 1 to 2 cm along the inner aspect of the antihelical fold to tattoo the cartilage along the planned excision path to ensure that sufficient antihelical contour is maintained. Dissection proceeds along both the anterior and posterior surface of the conchal bowl, and a kidney bean–shaped piece of conchal cartilage ( Figure 7-1 ) is harvested while leaving sufficient cartilage at the aforementioned key areas for support.
Because of its flaccidity and convolutions, it is best used when these characteristics are desired. It is usually used for reconstructing the lower lateral cartilage complex, for small onlay grafts, or for placement in the columella to provide tip support. However, it is a second choice to septal cartilage because of the inherent difficulty in obtaining and maintaining the desired shape and contour. While initial results of dorsal augmentation with auricular cartilage are often satisfactory, surface irregularities can become apparent with the passage of time. Furthermore, the irregular contour and limited supply of auricular cartilage often preclude its use.
Costal Cartilage
Because autogenous rib cartilage provides the most abundant source of cartilage for graft fabrication and is the most reliable when structural support or augmentation is needed, rib cartilage has been our graft material of choice for secondary rhinoplasty when sufficient septal cartilage is not available.
The choice of which rib to harvest depends on the planned uses and grafting requirements because the amount of cartilage required dictates whether the cartilaginous segment is needed from one rib, one rib and a portion of another, or two ribs. In general, the surgeon should choose the cartilaginous portion of a rib that provides a straight segment as it is often possible to construct all required grafts from a single rib. For dorsal augmentation with a dorsal onlay graft, we prefer to harvest cartilage from the fifth, sixth, or seventh rib, depending on which rib feels the longest and straightest. If additional grafts are needed, a part or the entire cartilaginous portion of an adjacent rib may be harvested.
Rib cartilage may be harvest from either the patient’s left or right side; however, harvesting from the patient’s left side facilitates a two-team approach. In female patients, the incision is marked several millimeters superior to the inframammary fold and measures 5 cm in length ( Figure 7-2 ). In males, the incision is usually placed directly over the chosen rib to facilitate the dissection.
The skin is incised with a scalpel, and the subcutaneous tissue is divided with the use of electrocautery. Once the muscle fascia has been reached, the surgeon palpates the underlying ribs and divides the muscle and fascia with electrocautery directly over the chosen rib. The dissection should be carried medially until the junction of the rib cartilage and sternum can be palpated. The most lateral extent of the dissection is demarcated by the costochondral junction. Identification of the junction is facilitated by the subtle change in color at the interface; the cartilaginous portion is generally off-white, whereas the bone demonstrates a distinct reddish-gray hue.
After exposure of the selected rib, the perichondrium is incised along the long axis of the rib. Perpendicular cuts are also made at the most medial and lateral aspects of the cartilaginous rib to facilitate reflection of the perichondrium.
A Dingman elevator is used to elevate the perichondrium superiorly and inferiorly from the cartilaginous rib. The subperichondrial dissection continues circumferentially as far posteriorly as possible until a curved rib stripper can be used to complete the posterior dissection. The curved rib stripper is slid back and forth along the rib, with care taken to remain between the cartilage and perichondrium until the undermining is complete.
The cartilaginous rib is cut near its attachment to the sternum and laterally where it meets the bony rib by making a partial-thickness incision perpendicular to the long axis of the rib using a No. 15 blade at the aforementioned junctions. The cartilaginous incision can then be completed with a Freer elevator using a gentle side-to-side movement. Once the cartilage segment is released both medially and laterally, the graft is easily removed from the wound and placed in sterile saline until the surgeon is ready to fabricate the grafts. If more grafting material is required, a portion of cartilage or the entire cartilaginous part of another rib is then harvested in a similar fashion ( Figure 7-3 ).
The donor site is checked to ensure that no pneumothorax has occurred by filling the wound with saline solution and the anesthesiologist applies positive pressure into the lungs. If no air leak is detected, a pneumothorax can be excluded. A 16-gauge angiocath catheter is inserted through the skin and placed in the bed of the wound to allow instillation of a long-acting local anesthetic at the conclusion of the procedure. The wound may then be closed in layers using 2-0 Vicryl sutures. Particular attention should be directed at reapproximating the perichondrium. It is important to close the perichondrium, muscle, and fascia layers tightly to prevent a palpable or visible chest wall deformity. A tight closure also helps “splint” the wound and reduce postoperative pain. Skin closure is carried out using deep dermal and subcuticular 4-0 Monocryl sutures.
If a pneumothorax has been diagnosed, this usually represents an injury only to the parietal pleura and not to the lung parenchyma itself. As such, this does not mandate chest tube placement. Rather, a red rubber catheter can be inserted through the parietal pleural tear into the thoracic cavity. The incision should then be closed, as previously described, in layers around the catheter. Positive pressure is then applied and the catheter is clamped with a hemostat until the surgeon is prepared for removal. At the end of the operation, the anesthesiologist applies maximal positive pressure into the lungs and holds this as the catheter is placed on suction and removed. A postoperative chest radiograph should be taken if there is any concern about the effectiveness of reestablishing negative pressure within the pleural space.
In older patients, ossification of the cartilaginous rib is a significant concern, and a limited computed tomography scan of the sternum and ribs with coronal reconstructions is recommended in those patients in whom there is a high index of suspicion. Despite appropriate preoperative screening, occasionally patients will present with premature calcification of the cartilaginous rib. Frequently, this is limited and occurs commonly at the junction of the osseous and cartilaginous portions of the rib. Small foci of calcification may also be found within the body of the rib cartilage itself. This can impair the preparation of individual grafts as well as act as a site of weakness often having a tendency to fracture during graft harvest. We have found that the use of a smooth diamond burr can also prove useful in contouring areas of calcification to salvage these uncommon circumstances. If the cartilage is unexpectedly found to be so extensively calcified at the time of the operation that it is unusable, we would then consider the use of irradiated donor cartilage, accepting the increased risks of progressive resorption over time. Irradiated homologous rib cartilage has been used successfully, but problems with infection, absorption, and warping limit its routine use in dorsal augmentation (R. O. Dingman, personal communication, 1980).
Operative Technique for Secondary Rhinoplasty
A systematic approach to the open rhinoplasty technique is helpful for obtaining consistent results. While an individualized approach is applied to each case and variations in operative steps and sequence occur, the general steps of open secondary rhinoplasty ( Table 7-2 ) proceed in the following sequence: incisions, skin elevation, intraoperative diagnosis and assessment of grafting requirements, septoplasty/septal cartilage harvest, dorsal modification, establishment of desired tip projection and reconstruction of the nasal tip complex, osteotomies, final tip cartilage positioning and shaping, wound closure, and application of splints and dressings.
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