The middle nasal vault is a sensitive region of the nose from both an esthetic and a functional perspective. It is critical for the rhinoplasty surgeon to properly evaluate and identify abnormalities of the middle vault when considering patients for primary or secondary surgery. This article addresses the surgical management of the cosmetic deformities and functional deficits of the middle vault and provides guidance for avoiding complications in this structurally critical region of the nose.
Key points
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The middle nasal vault is a critical region of the esthetics and function of the nose.
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Internal valve collapse is associated with abnormalities that arises in the middle vault.
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The thinnest nasal skin is over the middle third, and irregularities are often not well masked.
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Proper resuspension of the upper lateral cartilages during rhinoplasty will prevent postoperative cosmetic deformities and nasal obstruction.
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Dorsal hump reduction may unmask underlying middle vault abnormality and should be accompanied by appropriate grafting when indicated.
Introduction
Successful rhinoplasty is contingent on the appropriate evaluation of matching anatomic deformities to surgical strategies. The surgeon must understand the structurally sensitive regions of the nose and the implications of surgical alteration to both cosmesis and nasal function. The middle nasal vault is a critical anatomic region for the esthetics of the middle third of the nose as well as for maintaining nasal airflow. In patients evaluated for secondary rhinoplasty, middle third visual deformity and obstruction account for 2 of the 3 most common findings. In both primary and revision rhinoplasty, special consideration must be dedicated to addressing deformities and preserving supporting structures of the middle vault because this is an important point in the prevention of postoperative complications.
Introduction
Successful rhinoplasty is contingent on the appropriate evaluation of matching anatomic deformities to surgical strategies. The surgeon must understand the structurally sensitive regions of the nose and the implications of surgical alteration to both cosmesis and nasal function. The middle nasal vault is a critical anatomic region for the esthetics of the middle third of the nose as well as for maintaining nasal airflow. In patients evaluated for secondary rhinoplasty, middle third visual deformity and obstruction account for 2 of the 3 most common findings. In both primary and revision rhinoplasty, special consideration must be dedicated to addressing deformities and preserving supporting structures of the middle vault because this is an important point in the prevention of postoperative complications.
Anatomy
The middle nasal vault is difficult to understand because of its complex 3-dimensional anatomy and dynamic alteration with nasal airflow. The middle vault is also referred to as the cartilaginous vault and comprises cutaneous tissue, a musculoaponeurotic layer, upper lateral cartilages (ULC), dorsal septum, and intranasal mucosa.
The cutaneous tissue is often the thinnest over the middle third of the nasal envelope. The superficial musculoaponeurotic system (SMAS) over the nose contains the transverse nasal and levator alaeque nasi and has fascial insertions inferiorly along the anterior septum, the lower lateral cartilages (LLCs), and the columella. The paired ULC are deep to the SMAS and anchored superiorly to the undersurface of the nasal bones in the so-called K-area. Inferiorly, they are attached to the LLCs in the scroll region, and laterally, the soft tissue of the sidewall connects them to the piriform aperture. The ULC medially articulates with the dorsal edge of the cartilaginous septum, where the dorsal septum is often wider, forming a T- or Y-shaped orientation. When progressing toward the caudal aspect of the ULC, the angle between the septum and sidewall becomes more and more acute, narrowing the nasal airway. At this level, the reported normal angle in Caucasians is 10 to 20°. Intranasal mucosa is fixed to the undersurface of the ULC and is continuous with the septal mucosa.
The internal nasal valve is bound by the caudal aspect of the ULC anterolaterally, septum medially, and inferior turbinate posterolaterally ( Fig. 1 ). Because of its low cross-sectional area, nasal airflow is physiologically subject to the highest resistance in this area, as dictated by Poiseuille’s law. When accounting for Bernoulli effect, the high air velocity causes collapse at the internal valve, which can be pathologic if there is a lack of adequate structural support. In fact, approximately 1 in 6 patients with chronic nasal obstruction will have collapse of the internal nasal valve. When considering that the cross-sectional area of the internal nasal valve decreases by 25% after reduction rhinoplasty, it is not surprising that many patients have postoperative obstruction. Therefore, it is essential to address the middle vault effectively to avoid causing iatrogenic weakening of the nasal valve or exacerbating stenosis in patients with unfavorable anatomy.
Preoperative planning and preparation
Evaluation of the rhinoplasty patient is paramount before any surgical intervention is planned. The surgeon should be thorough in inquiry of desires and expectations of the patient and differentiate functional and cosmetic concerns. The patient should relay which specific esthetic features are bothersome and the anticipated change. Surgery should be avoided if the patient’s expectations are unrealistic or there is any indication of significant psychological abnormality suggesting body dysmorphic disorder. Preoperative photographs should be taken and reviewed with the patient to facilitate discussion and education of the areas of concern. Morphing imaging software can be additionally helpful in demonstrating a reasonable result and if that is an acceptable outcome for the patient.
A detailed history should be taken regarding nasal obstruction with laterality, alleviating or exacerbating factors, prior interventions, and any concomitant sinonasal disease. Prior nasal surgery, facial trauma, history of severe diabetes, granulomatous or bleeding/clotting diseases, smoking, and intranasal drug use are also important to document. The surgeon should always inquire regarding anticoagulation use, including supplements that alter the clotting cascade and heavy nonsteroidal anti-inflammatory drug use. In the case of revision surgery, review of prior operative reports is beneficial if records are available.
Physical examination should include facial and nasal esthetics as well as a functional analysis. The middle vault correlates externally with the middle third of the nose and is best viewed from the frontal and lateral views. General observation should include patient height, facial proportions, overall skin quality and thickness, scars, and obvious deformities. Special consideration is given to the skin overlying the middle vault because it is often the thinnest of any region of the nose. The frontal view will reveal a narrow or wide middle vault, or asymmetry/deviation of the middle third that could indicate dorsal septal deviation or twisting ( Fig. 2 ). A lack of appropriate shadowing along the dorsum would suggest underprojection. In patients with prior surgery, the hourglass or inverted V deformity is visible from the frontal view and would create an interruption of the smooth brow-tip line, indicating poor middle vault support.
The lateral view shows projection and shape of the middle third. Ideally, the nasal dorsum should be a straight line from the radix to the tip in male patients and in females, a very slight concavity present for the supratip break. Overprojection is often a result of a dorsal hump, essentially overdevelopment of the cartilaginous dorsal septum, especially the anterior septal angle ( Fig. 3 ). Tip rotation/projection and radix height should be noted because tip ptosis and a low radix produce a pseudohump ( Fig. 4 ). Inadequate chin projection can have a similar effect in creating the illusion of a larger nose. Pollybeak deformity is also apparent on lateral view and refers to the situation when the supratip projects farther than the tip. This can be a result of addressing the bony but underresection of the cartilaginous portion of a dorsal hump and can also be due to fibrous tissue formation at the supratip after cartilaginous dorsal hump and anterior septal angle overresection. Underprojection of the middle third can be a result of prior overaggressive dorsal hump reduction, dorsal cartilage resection during septoplasty, or a septal perforation causing a saddle nose deformity ( Fig. 5 ). Palpation of the nose provides adjunctive information to the visual examination, including skin quality, dorsal hump composition, nasal bone length, and lateral nasal wall support. Also, placement of a gloved thumb and second finger on either side of the intranasal dorsal septum can give additive information about intrinsic septal deviation.
The functional examination focuses on the intranasal static and dynamic aspects of inspiratory airflow. A static examination should include identification of septal deviation or perforation, ULC collapse, inferior turbinate hypertrophy, as well as any nasal bone or external valve/intervalve abnormality ( Fig. 6 ). While occluding the contralateral naris, the surgeon asks the patient to inhale through the nose with mild force to evaluate for dynamic collapse. Inadequate force may not unmask collapse, whereas an overly forceful inhalation will cause there to be collapse that may not be pathologic. Careful assessment of the true location of obstruction is critical to addressing the correct level of collapse with the appropriate surgical strategy. In lieu of the Cottle maneuver, the surgeon places a small-tipped instrument (eg, cerumen loop) to support specifically the area of objective collapse while the patient repeats the inhalation to assess for subjective improvement.
Procedural approach
Although endonasal approaches exist for certain aspects of middle vault surgery, the surgical exposure is best optimized with the external rhinoplasty approach. For the purposes of this article, the open technique is highlighted, as are the areas where an endonasal approach is feasible.
Preparation
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Patients undergo induction of general anesthesia and endotracheal intubation. The head is placed in a neuro headrest in a neutral position. The endotracheal tube is sewn to the precise midline mentum to facilitate intraoperative visual assessments of symmetry and to avoid pulling the nose to one side. The surgical lights are also placed in the midline so as not to cast asymmetric shadows.
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Lidocaine 1% with 1:100,000 epinephrine is injected into the nasal soft tissue envelope and septal mucosa with a portion submucosally for hydrodissection. Pledgets soaked in 1% tetracaine/0.05% oxymetazoline are placed in the nasal cavity. Mineral oil/petrolatum ophthalmologic lubricant is placed in the eyes.
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The face and neck are prepared with Poloxamer 188–containing wash and povidone-iodine 10% solution, and a head wrap is placed with a sterile towel. Appropriate sterile draping is performed.
External Approach
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An inverted V columellar incision is carried out with a number-15-c blade midway between the alar base and anterior aspect of the naris, taking care not to injure the medial crura of the LLC. Vertical columellar incisions are performed. While retracting the ala with a skin hook and everting the lateral crus, marginal incisions are performed at the caudal aspect of the lateral crura. The marginal and columellar incisions are joined while maintaining 3-point countertraction, and the nasal envelope is dissected from the LLCs in a submuscular plane.
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The anterior septal angle is identified, and the submuscular dissection is carried out over the dorsal septum where the ULC and the middle vault are exposed. The dissection plane should be just superficial to the cartilage to ensure adequate thickness of the overlying soft tissue.
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Standard open septoplasty can be performed at this point for resection of deviated septal elements and cartilage harvest for grafting.
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If a bony hump is to be reduced, a Joseph periosteal elevator is used to create a subperiosteal pocket. In the case that osteotomies are expected, this dissection should not be carried out laterally to preserve soft tissue support of the nasal bones.
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At the termination of the case, closure is performed with a single 5-0 polydioxanone (PDS) deep stitch in the midline columella, 6-0 fast absorbing gut interrupted stitches for the skin of the inverted V incision, and 5-0 chromic for marginal incisions when grafts are placed.
Widening of the Narrow Middle Vault
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Spreader grafts are the mainstay of widening the middle vault. Using septal cartilage either from open septoplasty or via a hemitransfixion incison, unilateral or bilateral grafts are created in a long rectangular shape with beveled ends. These grafts should be 1 to 2 cm in length, 1 to 4 mm in width, and no more than 5 mm in height so as not to impinge on the nasal airway.
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Mucosa is elevated from the dorsal septum and the undersurface of the ULC, wherein the ULC are carefully disarticulated from the dorsal septum with a Freer or Cottle periosteal elevator. The graft or grafts are placed between the anterior aspect of the ULC and the dorsal septum ( Fig. 7 ). These grafts can be held in place with either Brown-Adson forceps or a 27-gauge needle placed through all 3 structures. Several 5-0 nylon sutures are then used to secure the graft in place ( Fig. 8 ).
