Nose and paranasal sinuses

This chapter is divided into two sections, dealing with the nose and paranasal sinuses, respectively.

Nose

Core Procedures

Endoscopic ligation of the sphenopalatine artery
Septorhinoplasty

Surface landmarks

The proportions of the nose and face should be carefully evaluated ( Fig. 8.1 ). The angle of rotation and tip projection, height of the dorsum and any existing asymmetry are often key points to be addressed during surgery. A caudal septal deviation may be clearly visible on the basal view of the nose. The thickness of the soft tissue envelope is variable and is assessed; any irregularity resulting from surgery is likely to be visible and palpable in the setting of a thin overlying soft tissue envelope.

Fig. 8.1, The adult male nose. A , Basal view. B , Frontal view. The face can be divided into horizontal thirds and vertical fifths, with the nose filling the central segment in terms of both width and height. The basal view may also be divided into horizontal thirds, with the nostrils filling the lower two-thirds.

Clinical anatomy

Although the terms ‘concha’ and ‘turbinate’ are often used interchangeably, anatomists rarely use the latter term, while clinicians rarely use the former; in this chapter, turbinate is used to describe the bony structures, together with their overlying soft tissue and mucosa that are encountered during surgery. The middle turbinate acts as a useful landmark during surgery to help with orientation, and therefore is preserved where possible (see Fig. 8.15 ).

The external nose consists of paired nasal bones, and lateral (upper lateral) and major alar cartilages (lower lateral) ( Fig. 8.2 ). The paired nasal bones vary in thickness and width, which is of significance in planning osteotomies. The superior margin of the lateral cartilage inserts on to the undersurface of the nasal bones. The nasal bones, septum and lateral cartilages form the dorsum. The lateral and major alar cartilages are attached by fibrous tissue, often forming a scroll. The infra-tip break describes the profile of the nose where the inferior tip lobule turns into the columella, and the rhinion is a descriptive term for the point at the lower end of the median suture joining the nasal bones.

Fig. 8.2, The bony and cartilaginous skeletons of the nose. A , The external nose, frontal view. B , The external nose, lateral view. C , An inferior view of the cartilages. D , The nasal cavity, medial wall. E , The nasal cavity, lateral wall (left side).

The major alar cartilages and caudal cartilaginous septum determine the structure of the tip of the nose; asymmetry is common. The nasal septum is formed posteriorly by the vomer, posterosuperiorly by the perpendicular plate of the ethmoid, and anteriorly by the quadrilateral cartilaginous septum. Attachment to the anterior nasal spine, a projection of the maxillary crest, the maxilla and the vomer is important in providing stability to the nose. Deviations and deformities in these structures are common and may lead to nasal obstruction.

The perpendicular plate of the ethmoid bone (part of the bony nasal septum) articulates with the undersurface of the nasal bones and provides support to the dorsum of the nose. A midline bony spine deep to the fused nasal bone projects inwards to articulate with the perpendicular plate of the ethmoid and fuses with the fibrous tissue connecting the lateral nasal cartilages and cartilaginous septum. This is known as the keystone area and provides essential support to the nasal dorsum.

Significant nasal growth occurs from the age of 8–12 years, with a slightly longer duration in males, and is usually completed by the age of 15–16. The cartilaginous nasal septum is an important growth centre in the developing midface. Surgery in the paediatric population should therefore be delayed if possible, and should be conservative when it is performed.

Surgical approaches and considerations

Endoscopic ligation of the sphenopalatine artery

In the setting of intractable or recurrent epistaxis, arrest of haemorrhage by surgical ligation or interventional radiology is required when conservative management has failed. The majority of bleeds requiring surgery arise posteriorly, from the territory of the sphenopalatine artery; the exceptions are those complicating facial trauma, when the anterior ethmoidal artery is often involved.

The sphenopalatine artery may be approached endoscopically as it leaves the sphenopalatine foramen. The foramen transmits the vessel from the pterygopalatine fossa and is found posterior to the posterior wall of the maxillary sinus, at the posterior part of the middle turbinate. For inexperienced surgeons, a large middle meatal antrostomy, allowing clear identification of the posterior wall of the maxillary sinus, may help correct placement of the mucosal incision. More experienced surgeons may palpate the transition from the softer posterior fontanelle of the maxillary sinus to the hard palatine bone. A wide mucosal incision is made on the lateral nasal wall, posteroinferiorly to the antrostomy, on to the palatine bone. The flap is elevated in a subperiosteal plane, looking for the crista ethmoidalis, which is a reliable landmark for the artery as it emerges through the foramen. The artery may emerge as a single vessel but often has several branches. Each branch must be ligated (usually with bipolar diathermy or with vascular clips) ( Fig. 8.3 ).

Fig. 8.3, Endoscopic left sphenopalatine ligation. A wide maxillary antrostomy has been performed to expose the posterior wall of the maxillary sinus (MAX). A mucosal flap has been elevated in a subperiosteal plane. The sphenopalatine artery has been identified (light blue arrow) emerging from the sphenopalatine foramen behind the crista ethmoidalis (dark blue arrow).

Septorhinoplasty

When congenital or post-traumatic deformity of the nose results in functional obstruction of the nasal airway, this may be corrected by reshaping the septum (septoplasty) or external nose (rhinoplasty). Surgery may also be requested for aesthetic reasons.

Septorhinoplasty may be performed endonasally. An incision is made through the skin of the nasal vestibule and between the major alar and lateral cartilages in the scroll area, in order to access the nasal dorsum, and along the caudal edge of the nasal septum. The soft tissue envelope is elevated off the structures of the dorsum in a plane deep to the superficial musculo-aponeurotic system (SMAS) ( Fig. 8.4 ).

Fig. 8.4, Closed approach septorhinoplasty. The surgical plan is mapped on to the surface; a dorsal hump has been removed and the components (nasal bones, lateral cartilage and septum) are being removed in a mass, via an endonasal incision. Osteotomies will be performed, along with partial resection of the cephalic margin of the major alar cartilages, to increase tip rotation and to reduce volume in the tip.

Better access may be achieved using an open approach, making an incision through the skin of the columella and taking care not to damage the medial crura of the major alar cartilages. This affords excellent exposure of the nasal bones, septum, and lateral and major alar cartilages. The bones may be mobilized and reshaped with osteotomies, and the lateral cartilages may be repositioned to correct deviations of the dorsum. The dorsum may be reduced, removing parts of the nasal bones, lateral cartilages and septum, or augmented by graft material.

The tip may be adjusted by suturing, cutting or augmenting the shape and size of the major alar cartilages ( Fig. 8.5 ).

Fig. 8.5, Open approach septorhinoplasty. An incision has been made in the skin of the columella and the nose has been ‘degloved’ in a plane below the superficial musculo-aponeurotic system. This reveals the paired lateral and major alar cartilages. The attachment of the lateral cartilages to the septum has been divided to allow placement of a ‘spreader graft’ (arrow) that will lateralize the lateral cartilage and thereby increase internal cross-sectional area, improving the nasal airway and reducing obvious asymmetry externally.

Deviations of the septum are corrected by judicious resection of cartilage and bone, maintaining or repairing attachments to the lateral cartilages, medial crura of the major alar cartilages and anterior nasal spine. Excessive resection of cartilage may lead to a ‘saddle nose’, depression or ptosis of the tip ( Fig. 8.6 ).

Fig. 8.6, Open septoplasty. An incision has been made in the skin of the columella and the nose has been ‘degloved’ in a plane below the superficial musculo-aponeurotic system. The attachment of the medial crura of the major alar cartilages has been released, and the mucosa of the septal cartilage has been fully elevated bilaterally in a subperichondrial plane. This has allowed excellent access to the anterior cartilaginous septum.

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