Nasal Anatomy
blood supply:

• ophthalmic –> anterior ethmoidal and dorsal nasal (internal carotid)
• facial –> superior labial/columellar, angular, lateral nasal (external carotid) 
  • Columellar is sacrificed in open tip rhinoplasty
  • Lateral nasal is 2-3mm above alar groove (primary blood supply to the tip when columellar is sacrificed)

Innervation

• Nose is innervated by ophthalmic and maxillary branches including supratrochlear and supraorbital
• septum is innervated by the septal branch of the anterior ethmoidal artery

Musculature

• • levator labii superioris alaque nasi –> external nasal valve patency
  • depressor septi –> shortens the lip and decrease tip projection
    • smiling deformity – when the depressor septi decreases tip projection when the patient smiles.

nasal vaults

• The upper vaults consist of the paired nasal bones. These vary in length, but are typically 2-2.5cm long, widest at the nasofrontal suture and narrowest at the nasofrontal angle.
• The middle vault includes the upper lateral cartilages and dorsal septum. The upper lateral cartilages are posterior to the nasal bones, approximately 6-8mm. This is called the keystone area and is the widest part of the nasal dorsum. The middle vault also contains the internal nasal valve.
  • internal nasal valve is bordered by the caudal edge upper lateral cartilage, the septum, anterior portion of the inferior turbinate, and nasal the floor
  • important for regulating airflow resistance. Its normal angle is 10-15 degrees and is the narrowest portion of the nasal aperture contributing up to 50% of nasal airway resistance
  • Cottle maneuver tests for internal nasal valve collapse – pulling the ipsilateral cheek laterally –> Improved air movement confirms internal nasal valve collapse
• lower vault- which is composed of the lower lateral cartilages, begins with the region of abutment between the ULC and LLCs- called the scroll area. The lower lateral cartilage is composed of the medial, middle and lateral crura. angle of divergence is between 30-60 degrees.
  • In the Asian population, the ULC and LLC lengths are similar to non-asians, but the heights are much shorter.
  • The external nasal valve is also part of the lower vault and is bounded by the lateral crus, ala, and septum. nostril collapse on inspiration –> incompetence of the external nasal valve.
  • The septum is a quadrangular piece of cartilage that articulates with perpendicular plate of ethmoid and vomer
• turbinates – paired bony structures that regulate and humidify inspired air. The majority of airflow is through the middle meatus, but the majority of airflow resistance is at the internal nasal valve. These structures can become hypertrophied in patients with septal deviation.
  • If turbinate hypertrophy is noted, afrin may be used to differentiate between bony and mucosal hypertrophy.

Approaches to rhinoplasty
closed approach uses hidden incisions

• advantages – decreased edema, operative time, recovery
• Disadvantages – poor visualization, difficult dissections.

alar incisions:

Transcartilaginous incision		Located at the level of the lower lateral cartilages
Intracartilagionous incision		Located between upper lateral cartilage and lower lateral cartilage
Marginal incision		Located in alar rim

septal incisions:

Transfixion incision		Incision made at membranous and cartilaginous junctions (more for caudal work and hanging columella)
Limited transfixion		Same, leaves attachments of medial crural footplates
Hemitransfixion		Unilateral incision at junction of caudal septum, mucocutaneous junction
Killian incision		Posterior to caudal septum (more for deviated septum)

grafts

• nasal tip is dependent on the LLC, soft tissue, and suspensory ligaments of the LLC and ULC
  • Grafts that increase tip projection – columellar strut grafts, onlay tip grafts, shield grafts, and subdomal grafts
  • Sutures that increase tip projection – medial crural sutures, interdomal sutures, and transdomal sutures.

Increasing tip projection: Grafts and sutures are aimed for tip projection and infratip/lobule definition

• Medial crural sutures: between medial crura, stabilize collumellar strut, may also use medial crural septal sutures which include septum and causes rotation of drooping nasal tip
• Interdomal sutures: placed between domes of LLC, increase projection
• Transdomal sutures: placed between medial and lateral portions of single LLC
• Columellar strut: between medial crura
• Onlay tip graft: lies horizontally over LLC and alar domes
• Shield Graft: rests on anterior middle crura
• Subdomal graft: used mainly to correct pinched nasal tip deformity –> bar shaped graft in pocket under the domes
  • Pinched nasal deformity: occurs from decreased interdomal distances
• Septal extension graft
• Inadequate projection? –> cephalic trim, columellar strut, septal extension, medial crural suture, transdomal sutures

Decreasing tip projection: may decrease soft tissue attachments of LLC as well as transection of lateral and medial crura

tip deformities of the nose

• pinched nasal tip deformity – decreased interdomal distances, corrected with subdomal grafts.
  • subdomal grafts – bar shaped grafts that go under under the dome
• Polybeak deformity – fullness of the supratip area and underprojection of the nasal tip.
  • Treatment – increasing tip projection.
• boxy tip, bulbus tip, and parenthesis tip.
• Tip rotation: increased tip rotation may be obtained with cephalic trim of LLC, caudal septum resection, columellar strut grafts. Suture techniques used to suspend the LLC to decrease tip projection release attachments of LLC and use septal extension grafts
• Tip Definition: wide angle of divergence can create variations of a boxy tip. This is usually corrected with suture techniques of the LLC as well as lateral crural strut grafts.
• Parenthesis tip:  caused by vertical orientation of LLC, corrected with lateral crural strut graft
• Bulbous tip: caused by convexity of LLC or wide angle of divergence, treated by cephalic trim and transdomal sutures, and lateral crural mattress sutures if the LLC is convex

Nasal Dorsum.

• dorsal hump –> hump reduction with a rasp prior to manipulation of the septum because an adequate strut must be left in place.
  • over zealous hump reduction –> inverted V deformity (nasal bones are separated from the ULC) and Open roof deformity (separation of the septum and the dorsal sidewalls)
• Augmentation, septal cartilage grafts are used, diced (turkish delight) or whole, auricular or costal cartilage, irradiated, or synthetic implants. Dorsal only grafts mainly improve contour, radix grafts are used typically on upper dorsal defects.
  • hydroxyapatite has been used for dorsal augmentation or “liquid rhinoplasty.” –> injection above the periosteum in in the SMAS plane (subperichondrial plane). This should only be used for nasal dorsum an sidewalls

osteotomies

• to narrow or widen the bony vault. Medial osteotomies should be performed prior to lateral osteotomies.
• primary complication of osteotomies is rocker deformity (medial osteotomies that go beyond the thick portion of the radix, causing rocking of the lateral portion distally after positioning of the proximal portion more medially)

Alae

• Grafts used for alar contour, but excisions for large alae
• alar batten grafts, rim grafts, lateral crural strut grafts, turn over grafts
  • alar batten graft for external nasal valve collapse (from the piriform aperture to the paramedian position in the alar sidewall)

 

• Nasal Alae: grafts mainly for alar contour, may be anatomic or nonanatomic grafts
  • Overresection of LLC may cause alar rim deformities
  • Alar batten graft: pocket from piriform aperture to paramedian position in alar sidewall –> used for external nasal valve collapse

• Alar rim graft: subcutaneous pocket above and parallel to alar rim, corrects retraction
• Lateral crural strut graft: placed underneath lateral crura typically after cephalic trim, extending to piriform aperatur inferior to alar groove, corrects lateral crural malposition or external nasal valve collapse, concavity of lateral crura and boxy tip
• Lateral crural turnover graft: cephalic portion of lateral crura turned over onto remaining caudal lateral crura, improves shape of lateral crura
• Wide Alae: corrected with wedge excisions

airway obstruction

• Evaluation – rhinomanomatry for dynamic evaluation, nasal endoscopy or CT scan.
• Deviated septum can cause functional airway obstruction as well as turbinate hypertrophy and alar collapse.
• Septum – resection, scoring, strut suture or graft. Spreader grafts may be placed between the dorsal septum and ULC in the sub mucoperichondreal pocket to widen the angle and improve the airway. When the septal cartilage is harvested, at least 10mm should be left to prevent septal collapse and saddle nose deformity
  • Saddle nose deformity is a collapsed dorsum from a dorsal septal fracture. typically reconstructed with cartilage spreader grafts.
  • normal internal nasal valve angle – 15 degrees
• Turbiate hypertrophy – contralateral side of septal deviation typically has compensatory turbinate hypertrophy –> outfracture or submucosal resection.
  • Empty nose syndrome results from complete removal of the inferior turbinate

complications of rhinoplasty

• CSF leak – dura may be torn from disruption of the perpendicular plate. –> watery rhinorrhea or headaches. Test for beta 2 transferrin.
  • Treatment is typically conservative with watchful waiting and antibiotics.
• septal perforation. – bilateral mucosal tears –> crusting, whistling, bleeding.
  • Treatment is with local flaps and cartilage grafts.