By:

Dr. Pratima Jaiswal

HOD, Dept. of Anatomy

Govt. Medical College, Kota

Rajasthan, INDIA

Outline of the presentation is as follows

External anatomy of nose

Bony pyramid of nose

Cartilaginous vault of nose

Soft tissue covering

Nasal musculature

Nasal septum

Lateral wall

Nerve supply

Blood supply

• Consists of: – External Nose

– Nasal cavity

• The external nose :– Is a pyramidal projection

of face

– tip

– Root

– dorsum

– ala of nose bounding inferiorly a pair of nostrils

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T H E N O S E

• glabella: upper narrowed end of nose joins with forehead

• nasion: Upper end of internasal suture

• rhinion: Lower end

• nasofrontal angle: A depression at nasion while rolling down finger from glebella

• Limen vestibuli: jn. Between upper and lower cartilages

• Nasolabial angle : b/w columella and upper lip

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Osteocartilaginousframework:

• Bony pyramid –upper 1/3rd

• Cartilaginous part – lower 2/3rd (Upper & lower cartilaginous vault)

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E x t e r n a l n o s e

• Formed by Nasal bones and frontal process of maxilla

• Paired nasal bones, each one is tapered, thin and bevelled below but gradually thickens upwards encroaching upon the nasal cavity – Two nasal bones form a crest in midlineArticulates – Upwards with nasal spine of frontal &

perpendicular plate of ethemoid – Laterally with frontal process of maxilla (is

thick below n thin above) by nasomaxillarysuture

– Variation in size ,shape or asymmetry of nasal bones seen, small nasal bones pose problem in rhinoplasty must be recognized preoperatively

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B o n y p y r a m i d

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Cartilaginous vault

• Paired, Triangular ULC and part of septal cartilages enclosed in common perichondrial sheath

• Base at septum, Apex at pyriform fossa

• Cephalic attachment to nasal bones– Nasal bones overlap over ULC 1cm– Held in place with intimate fusion b/w

perichondrium and periostium

• Medial borders are thick and continuous with dorsal border of septal cartilage.

• Laterally ULC are short of pyriform edge of maxilla, the gap is filled by dense fibrofatty tissue (empty triangle)

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Upper Cartilaginous vault-cont

• Inferiorly caudal edge is rolled outwards & upwards forming a scroll which widens dorsal and lateral walls

• K area-– junction b/w nasal

bones,ULC, septalcartilage & vertical plate of ethemoid ,

– is centre of support of nasal roof

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Upper Cartilaginous vault-cont

• Lowermost part of nasal fossae, bounded superiorly by caudal edge of ULC is vestibule.

• Lined by thin skin having coarse hairs and sebaceous , sweat glands.

• Internal nasal valve-triangular area bounded lat by caudal edge of ULC ,septum medially, nasal cavity floor inf,is narrowest part of nasal cavity

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Upper Cartilaginous vault-cont

• Paired alar cartilages (few sesamoid cartilages)

• can move freely over ULC and septal

• Contribute to formation of lobule, columella and ala.

• Each one made up of single piece of C-shaped cartilage ,having parts medial, middle and lateral crura

• Lateral crus - 1 mm in thickness

Starts at domal segment and arch outwardly convex

• Middle crus-

from columella to lateral crus

Divided into domal and lobular segment

• Medial crus-

It starts at footplate and extends into columella

lies under the thin skin of columella and two med crura are attached by fibrous tissue and to lower end of septum by membranous septum

Lower cartilaginous vault

• Soft triangles- area of soft tissue infront of nares, consist of external skin, vestibular skin with scanty areolar tissue and regarded as sign of beauty in a feminine nose.

• Laterally extend towards pyriform edge to variable extent

• the contour of ala are rounded due to fibrofatty tissue, adherent to smaller alar cartilages.

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Lower cartilaginous vault- cont

• Anderson has compared Lower Lateral Cartilage to a tripod

1. two long legs of lateral crura,

2. A short leg of medial crurajoined to each other

• Tripod is supported by ULC, septal cartilage,soft tissue at base of columella & membranous septum

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Lower cartilaginous vault- cont

• Lateral crural complex

• Thickness of overlying skin

• Ligaments and fibrous attachments of nasal tip structures

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Factors affecting shape & position of nasal tip

• Extends between upper lip and tip of the nose

• Divided into three almost equal parts , upper –lobular, middle and basal part –wider

• Consist of paired medial crura with covered skin, variable length of crura may produce projecting or depressed tip

• Anteriorly- diverging crura form an angle of 30 degrees for tip formation.

• Posteriorly - also diverge to receive post septal angle, adjoining septal cartilage and anterior nasal spine.

• Shape of columella depends on size and shape of medial crura. 15

Columella

• Nasal skin : thick over-nasion, supratiparea and thin at rhinion– over lower part is thicker , firmly adherent

to cartilages

– over nasal bones and ULC is mobile

• Subcutaneous tissue covering thickens gradually downwards from rhinion

: has 4 layers

1. Superficial panniculus

2. Fibromuscular layer

3. Deep fatty layer

4. Periosteum/ perichondrium

• Incisions in rhinoplasty are given deep to all these layers since blood vessels run in deep fatty layer.

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Soft tissue covering

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Elevators:• Procerus• Levator labii

superioris alaquenasi

Depressors:• Alar part of nasalis• Depressor septiCompressor:• Tranverse part of

Nasalis• Compressor narium

minor Dilators:

dilator naris

Nasal Musculature

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• Bony :– perpendicular plate of

ethemoid– vomer postcontribution from – sphenoidal crest n rostrum – nasal spine of frontal bone– nasal crest by maxillae and

palatines

• Septal cartilage : – quadrilateral cartilage ,is – unossified part of vertical plate

of ethemoid– is mobile permits side to side

movements– Is major support mechanism of

nose

Nasal septum

• A small contribution from ULC and LLC to ant nasal septum

• Dorsal border of septum is expanded ,extends upwards under nasal bones to variable distance.

• Caudal part effects position of columella.

• Ant septal angle-jn of dorsal & caudal borders.(supratip)

• Post septal angle-jn bet caudal &inf border,is anchored to ant nasal spine.

• Subperichondreal &subperiostealplanes are not continuous hence attempt to join these planes may tear mucous memb. 19

Nasal septum-contNasal septum-cont

Membranous septum • Between septal cartilage &

columella ,consist of vestibular skin with intervening areolar tissue.

• post diverging ends of medial crura receive post part of caudal edge of septal cartilage ,columella can be retracted easily from septum along entire length.

• In septoplasty integrity of the memb septum should be preserved.

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Nasal septum-cont

• Formed by sup, middle &inf turbinates and their meatuses• Middle and inferior turbinate are imp surgically• Middle turb is extension of ethemoid

bone,hypertrophy/malposition can cause nasal obstruction,headache.

• Inf turb ,separate bonecovered with ciliated epithelium,erectiletissue and venous sinuses. 21

Lateral wall

Sensory supply:• By branches of ophthalmic

and maxillary div. Of trigeminal

• infra trochlear branch-skin of root and adjacent sides of nose

• infra orbital, external nasal nerve- skin of lower half of nose

• terminal branches of palatine nerves – skin of base of columella

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Nerve supply- external

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Nerve supply- internal

• Dorsal and external nasal branch of ophthalmic artery

• Infra orbital br. of maxillary artery

• Lateral nasal and angular br. of facial artery

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Arterial supply- external nose

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Plane of dissection to mobilise soft tissue should be closer to bone or cartilage to avoid injury to muscles and superficial vessels

Arterial supply

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Venous drainage

•External veins of nose drain to angular and opthalmic veins

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