21 Endonasal Rhinoplasty
Key Concepts
The endonasal approach to rhinoplasty allows the surgeon to perform many of the same maneuvers as the open rhinoplasty approach.
Excellent visualization of the nasal tip structures can be achieved with the cartilage delivery technique.
Because there is no columellar incision, there is no risk of problems with the healing of the columellar incision or columellar scarring.
Because there is less dissection with the endonasal approach, there may be less swelling.
Introduction
During the past decade, the external approach to rhinoplasty has been widely popularized. As is well documented in the literature, this is a useful approach for the procedure and offers distinct visualization advantages for teaching the procedure to residents.
Yet the endonasal approach to rhinoplasty also has some distinct advantages, including less surgical dissection, potentially more rapid execution, and the lack of a visible incision. Furthermore, the endonasal approach avoids the risk of a columellar scar or columellar healing problems, which can uncommonly include partial loss of the columella, requiring secondary reconstruction. Healing time may be reduced because there is less dissection and, in the authors’ experience, frequently less swelling.
To perform an endonasal approach, it is important for the surgeon to have a thorough understanding of the underlying anatomy. Some surgeons will mark the underlying anatomy on the skin surface. As for all rhinoplasty approaches, it is important to have a diagnosis of the underlying issues before starting the surgical procedure. It is also important to have a complete procedural plan before making any incisions. However, one must be prepared to amend the initial plan depending on the findings at surgery.
Background: Basic Science of Procedure
Sushruta Ayuveda was the first known person to describe external nasal surgery for reconstruction, around 600 BC in India. Rhinoplasty was described in the nineteenth century by Orlando Roe1 and Franz Joseph. Subsequently, rhinoplasty techniques were further refined and popularized by physicians such as Aufricht, Fomon, and Goldman.2,3 The endonasal approach, with the use of transfixion incisions, became the primary approach through most of the 1960s and 1970s. More recently, external rhinoplasty has become more popular than endonasal rhinoplasty. Despite this, many surgeons advocate for the use of the endonasal approach. For many patients the benefits of the endonasal approach are clear.
With both primary and revision cases, those that offer limited challenges are sometimes the most appropriate to address endonasally.4 Before performing a rhinoplasty procedure, it is important to have an understanding of nasal anatomy that includes osseous, cartilaginous, and ligamentous structures. Endonasal rhinoplasty can be used to improve the nasal tip, dorsum, or both. Incising, suturing, or excising portions of the tip cartilages can be used to alter the shape, projection, and rotation of the tip. Struts, tip grafts, and alar batten grafts can also be employed.
Pertinent Anatomy
An understanding of the anatomy of the nose is crucial when one is evaluating the rhinoplasty patient. The paired nasal bones provide the bony framework of the upper nose.5 Their attachments to the frontal bone and nasal processes of the maxillary bone complete the bony vault. The paired upper lateral cartilages and lower lateral cartilages, with their fibrocartilaginous support, provide the framework of the middle third of the nose, in addition to the septum and nasal bones. Specifically, the lower lateral cartilages form a fibrocartilaginous arch supporting the nasal lobule and nostrils.5 The nasal septum supports the nose along its entire length. It supplies the dorsal profile between the nasal bones and nasal tip.5 The caudal septum influences the appearance of the columella. To describe the dynamics of the tip, Anderson analogized nasal tip support to a tripod, with the lateral crura representing two legs and the conjoined medial crura the third leg.5 Other authors have likened tip dynamics to a cantilevered spring model.6
Tip support is dependent upon the relationship of the lower lateral cartilages to the soft tissue and their intrinsic strengths. Male and female noses differ with respect to nasolabial angles and the incidence of dorsal humps. The ideal nasolabial angle ranges from 90 to 115 degrees.7 In general, the angle is more acute in men and more obtuse in females.
Aesthetically, the nose should be symmetrical, proportioned, and balanced. The well-balanced nose is in harmony with the surrounding structures of the face. On analysis, one should be able to divide the face into equal horizontal thirds and vertical facial proportions equal to five eye widths across when viewed frontally.7
Patient Selection
Appropriate patient selection is critical for successful outcomes in endonasal rhinoplasty. Depending on the surgeon′s level of expertise, the endonasal approach can be used for both primary and revision rhinoplasty procedures. Patients with excessive asymmetry or scarring due to multiple prior procedures may benefit more from an open approach. Ideal candidates for an endonasal approach are those that may be more symmetrical, have less challenging goals for correction, and have limited diagnostic uncertainties. In contrast, even complex patients whose goals are met with limited resection or grafting might be best benefited by an endonasal approach.
It is important to obtain preoperative photographs. These should include at least frontal, lateral, base, and oblique views. Lateral photos with and without smiling are at times important to analyze possible changes in the nasal tip with smiling and should be taken so that the patient′s face is positioned in line in the Frankfort horizontal plane. Frontal, base, and oblique views provide the best way to assess side-to-side symmetry and reflect the views most seen by others in the day-to-day life of a patient.4
Technical Aspects of Procedure
Endonasal rhinoplasty can be used to address aesthetic issues in all aspects of the nose. Using the cartilage delivery technique, there is excellent visualization of the alar cartilages. Several types of maneuvers can be performed on the cartilages when exposed via delivery or closed technique. Portions of the lateral crura can be conservatively removed, incised, or reshaped with sutures. Tip grafts and struts can be placed and stabilized with absorbable sutures as needed. The nasal dorsum can also be managed through the same intercartilaginous incisions that are used in cartilage delivery.8,9
These and other maneuvers can be used to alter the nasal tip, including reshaping, narrowing, rotating, augmenting, and altering projection.
Surgical Instruments
A basic rhinoplasty set includes a sharp no. 15 blade scalpel, a no. 11 blade, nasal speculum, double ball retractors, single-prong hook, double-prong skin hooks, elevators, rasps, osteotomes, morselizer, crusher, Aufricht retractor, Fomon scissors, Stevens tenotomy scissors, Cottle-Neivert retractor(s), and sponges ( Fig. 21.1 ).
Patient Preparation
Patient preparation for the procedure starts with a prior discussion about the procedure, potential results, limitations and variations, risks, and the typical recovery course. Patients should also be instructed to avoid any medications or supplements that can predispose them to bleeding for the 2 weeks leading up to the procedure.
Endonasal rhinoplasty can be performed with general anesthesia, local anesthesia with intravenous sedation, or local anesthesia with oral sedation. Epinephrine within the local facilitates hemostasis. It is prudent for the physician to select the optimal anesthesia agents for the individual patient. Skin and intranasal markings should be completed before local anesthesia is injected.
Nasal Anesthesia
If the procedure is performed with oral sedation, it is particularly important to achieve adequate anesthesia by local infiltration or local blocks or both. The authors’ preference for local anesthesia is 1% lidocaine with 1:100,000 epinephrine. When injecting local anesthesia, it is important to avoid distorting key structures, as well as not to exceed a safe total dose of local anesthesia. Overinjection of local anesthesia can also distort the patient′s nasal anatomy or create avoidable swelling.
Surgical Approach
The incisions used to approach an endonasal rhinoplasty are varied, but the ones to be covered in this chapter will equip the surgeon for adequate management of the anatomy Video 21.1. Endonasal rhinoplasty is started by approaching either the nasal dorsum or the nasal tip. The marginal and intercartilaginous incisions are made adjacent to the endonasal proximal and distal edges of the lateral crura of the lower lateral cartilages. The marginal incision, combined with an intercartilaginous (IC) incision, provides delivery of the tip cartilage into the surgical field. The retrograde IC and cartilage-splitting approaches are nondelivery techniques.2 The IC incision is useful for trimming relatively small cephalic portions of the lobular cartilage,2 whereas the cartilage-splitting incision is used when there are more changes needed in tip rotation and supratip definition. Preservation of alar support, with integrity of the caudal lateral crus, is possible with both.10
The Marginal Incision
The marginal incision is made in the vestibular skin along the caudal margin of the lower lateral cartilage with a no. 15 blade scalpel ( Fig. 21.2a–f ). When making this incision, it is important to have a finger on the external skin so the depth of the scalpel can be palpated.