Anatomy of nose

NOSE

1. ANATOMY OF NOSE DR PRIYANKA

2. EMBRYOLOGY

3. OSTEOLOGY OF NOSE MAXILLA FRONTAL ( UNPAIRED ) ETHMOID ( “ ) SPHENOID ( “ ) INFERIOR TURBINATE LACRIMAL PALATINE NASAL BONES

4. Sphenoid bone Bone spanning the width of middle cranial fossa Consists of central body and three processes; greater and lesser wings and pterygoid process (pos. view)

5. 7 Sphenoid Bone (Floor of Cranium) (Green Colored Bone)

6. 8 Maxilla The largest bones of the face, except for the mandible and form, by their union, the whole of the upper jaw. Each assists in forming the boundaries of three cavities, namely, the roof of the mouth, the floor and lateral wall of the nose, and the floor of the orbit. Zygomatic , frontal, palatine and alveolar process Landmarks: Infra Orbital foramen : hole below the orbit, for blood vessels and nerves Alveolar process : arch of the maxilla containing the upper teeth Palatine process : horizontal projection of the maxilla forming the anterior ¾ of the hard palate.

7. 9 Maxilla

8. Lacrimal canal : groove posterior to frontonasal process, lacrimal bone and lacrimal process of inferior turbinate Infraorbital foramen Greater palatine canal

9. 11 Ethmoid Bone An irregularly shaped, spongy bone that provides the floor of the front part of the skull and the roof of the nasal cavity. The ethmoid consists of two masses of thin plates enclosing air cells and looks like a sieve. Landmarks: Lateral masses : form most of the wall between the nasal cavity and the orbits Perpendicular plate : forms the superior portion of the nasal septum Cribiform plate : forms the roof of the nasal cavity Olfactory foramina : small holes within the cribiform plate for passage of the first cranial nerve (for smell) Crista galli : upward extension of bone above the cribiform plate, acts as an anchoring point for one of the coverings of the brain. Nasal concha (turbinates) : two scroll-shaped projections with a mucus membrane on either side of the nasal septum. Function to cause air turbulence and trap inhaled particles.

10. Ethmoid bone - landmarks Cribiform plates Forms roof of nasal cavity, fits into the notch in frontal bone, foramina : olfactory nerve Horizontal and vertical lamella lamella Crista galli Attachment of the dura mater which secures brain in cavity

11. 14 Nasal Bones Bridge of nose Internal surface : groove for anterior ethmoidal nerve Superior border articulates with frontal bone Lateral border : frontonasal process of maxilla

12. 15 Lacrimal Bones Smallest and most fragile bone of the face Contains the lacrimal sac and the naso - lacrimal duct. Orbital surface : posterior lacrimal crest Btwn anterior and posterior lacrimal crest : lacrimal sac Lacrimal bone

13. 16 Palatine bones Fragile L shaped bone It contributes to the walls of three cavities: the floor and lateral wall of the nasal cavity, the roof of the mouth, and the floor of the orbit

14. Horizontal plate Posterior section of hard palate Perpendicular plate Part of the posterolateral walls of nasal cavity Greater palatine canal Orbital surface Part of inferior medial aspect of orbit Processes : Orbital process Sphenoid process Between the two : sphenopalatine notch Pyramidal process

15. 18 Inferior Nasal Conchae Extends horizontally along the lateral wall of the nasal cavity and consists of a lamina of spongy bone, curled upon itself like a scroll. Inferior Nasal Conchae

16. NOSE 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 19

17. EXTERNAL NOSE Osteocartilaginous framework: Bony pyramid –upper 1/3 rd Cartilaginous part – lower 2/3 rd (Upper & lower cartilaginous vault) 20

18. BONY VAULT 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 midline Articulates Upwards with nasal spine of frontal & perpendicular plate of ethemoid Laterally with frontal process of maxilla (is thick below n thin above) by nasomaxillary suture 22

19. 23 Cartilaginous vault

20. UPPER CARTILAGENOUS 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) 24

21. 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 25

22. LOWER CARTILAGENOUS VAULT 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

23. COLUMELLA 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 . 27

24. SOFT TISSUE COVERING Nasal skin : thick over- nasion , supratip area and thin at rhinion over lower firmly adherent to cartilages over nasal bones and ULC is mobile Subcutaneous tissue covering thickens gradually downwards from rhinion : has 4 layers Superficial panniculus Fibromuscular layer Deep fatty layer Periosteum / perichondrium Incisions in rhinoplasty are given deep to all these layers since blood vessels run in deep fatty layer. 28

25. NASAL MUSCULATURE Elevators: Procerus Levator labii superioris alaque nasi Depressors: Alar part of nasalis Depressor septi Compressor: Tranverse part of Nasalis Compressor narium minor Dilators: dilator naris 29

26. ARTERIAL SUPPLY Dorsal and external nasal branch of ophthalmic artery Infra orbital br. of maxillary artery Lateral nasal and angular br. of facial artery 30

27. 31

28. 32 Venous drainage External veins of nose drain to angular and opthalmic veins

29. NERVE SUPPLY TO EXTERNAL NOSE 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 33

30. NERVE SUPPLY TO INTERNAL NOSE 34

31. NASAL SEPTUM NASAL SEPTUM HAS 3 PARTS : COLUMELLAR :   Columellar septum. It is formed of columella Containing the medial crura of alar cartilages united together by fibrous tissue and covered on either side by skin . Membranous septum. It consists of double layer of skin with no bony or cartilaginous support. It lies between the columella and the caudal border of septal Cartilage. Both columellar and membranous parts are freely movable from side to side.

32. Septum proper. It consists of osteocartilaginous framework, covered with nasal mucous membrane. Cartilagenous portion composed of quadrilateral cartliage, contributions from lower and upper lateral cartilages.

33. Bony septum : mainly by perpendicular plate of ethmoid and vomer Minor contributions : crest of nasal bone nasal spine of frontal bone rostrum of sphenoid crest of palatine bone crest of maxilla anterior nasal spine of maxilla

34. Bony septum: perpendicular plate of ethmoid forms the superior and anterior bony septum, which is continuous above with the cribriform plate and crista galli. Vomer defined as keel shaped bone, extends anteriorly from spenoid and superiorly from nasal crest of maxilla and palatine bone. forms the posterior and inferior nasal septum and articulates by its two alae with the rostrum of sphenoid creating vomerinovaginal canals which transmit pharyngeal branches of maxillary artery.

35. The upper margin expands which is connected to the upper lateral cartilages. Bound firmly by collagenous fibres to the nasal bones And to the perpendicular plate of the ethmoid and vomer Inferior border of vomer articulates with nasal crest formed by maxillae and palatine bones. Anterior border articulates with perpendicular plate of ethmoid and septal cartilage inferiorly. Posterior border forms the free edge

36. LATERAL WALL OF NOSE The lateral wall of nose: Maxillary bone Ethmoid bone Sphenoid bone Inferior turbinate Lacrimal bone Palatine bone

37. The nasal turbinates are embryologically derived from a series of outgrowths from the foetal lateral nasal wall. The outgrowths form a series of ridges, referred to as “ ethmoturbinals ” which are separated by furrows. Each ridge has an anterior ascending portion and a posterior descending portion. The uncinate process develops from the descending portion of the first ridge, which is also known as the “ nasoturbinal ”

38. The agger nasi develop from its ascending portion. The second ridge forms the bulla lamella, or the bulla ethmoidalis when pneumatized . The middle turbinate develops from the third ridge, which is the first permanent ethmoturbinal . The fourth ridge, the second permanent ethmoturbinal , forms the superior turbinate. Based upon this, variations in development and pneumatization of the ethmoturbinals may lead to anatomical variations within the bony structures of the ethmoidal complex.

39. Nasal turbinates : The turbinates are the most prominent feature of the lateral nasal wall . They are usually three or sometimes four in number. These turbinates appear as scrolls of bone, delicate, covered by ciliated columnar epithelium. These turbinates sometimes may contain an air cell, in which case it is termed as a concha .

40. Inferior turbinate, meatus Largest turbinate and largest meatus Highest at the jnctn of ant and middle 3 rd (1.6-2.3 cm) Separate bone covered by thick mucous membrane Nasolacrimal opening in anterior portion of lateral wall of inferior meatus Slit like opening is protected by fold of mucous membrane, the plica lacrimalis or valve of Hasner

41. Middle turbinate/ meatus Portion of ethmoid bone It recieves drainage from the frontal, maxillary and antethmoidal cells hiatus semilunaris and ethmoid infundibulum . maxillary hiatus. ant and post fontanelles recesses terminalis

42. MIDDLE MEATUS Infundibulum – Air passage connecting the maxillary sinus ostium to middle meatus Hiatus Semilunaris – Gap between the uncinate process and bulla ethmoidalis . Medially it communicates with middle meatus. Laterally & inf it communicates with infundibulum

43. Middle turbinate  3 parts Anterior 1/3 rd : saggital plane : cribriform plate at the junction of medial and lateral lamella Middle 1/3 rd : coronal plane; lamina papyracea : ground lamella / basal lamella Posterior 1/3 rd : horizontal plane : lamina papyracea and perpendicular plate of palatine bone.

44. OSTEO MEATAL COMPLEX  The osteomeatal complex is the key anatomic area addressed by endoscopic sinus surgeons. Blockage of the osteomeatal complex prevents effective mucociliary clearance, thus leading to a stagnation of secretions and therefore leading to recurrent or chronic sinusitis.

45. OSTEO MEATAL COMPLEX The OMC is bounded medially by the middle turbinate, posteriorly and superiorly by the basal lamella, and laterally by the lamina papyracea . Inferiorly and anteriorly the OMC is open .

46. OSTEO MEATAL COMPLEX

47. Uncinate process : This is the most stable landmark in the lateral nasal wall. Horizontal and vertical limb It is a wing or boomerang shaped piece of bone. It attaches anteriorly to the posterior edge of the lacrimal bone, and inferiorly to the superior edge of the inferior turbinate . Superior attachment of the uncinate process is highly variable, may be attached to the lamina palyracea ( 80 % ),or sometimes to the middle turbinate or lie freee within middle meatus The configuration of the ethmoidal infundibulum and its relationship to the frontal recess depends largely on the behavior of the uncinate process

48. Variations in the superior insertion of the uncinate process are classified according to criteria developed by Landsber & Friedman A: Type 1 (insertion into the lamina papyracea ). B: Type 2 (insertion into the posterior wall of agger nasi cell). C: Type 3 (insertion into the lamina papyracea and junction of the middle turbinate with the cribriform plate). D: Type 4 (insertion in to junction of the middle turbinate with the cribriform plate). E: Type 5 (insertion into the skull base). F: Type 6 (insertion into the middle turbinate)

49. Uncinate attached to lamina : frontal sinus drainage : medial to uncinate process Attached to skull base : frontal sinus drains into infundibulum : disease from frontal sinus spreads to maxillary

50. The Agger Nasi Air Cell : Its an ethmoturbinal remnant present in nearly all patients ( 93 % ) The ANC is the most constant and anterior of the ethmoidal air cells. Located anterior to the vertical attachment of the middle turbinate to the skull base.

51. The degree of ANC pneumatization varies and has a significant effect on both the size of the frontal sinus ostium and the shape of the recess. If the ANC is small, then the “beak” of the frontal process of the maxilla, lying anteriorly and superiorly, will be prominent and extend posteriorly into the frontal recess, resulting in a narrow ostium . If the ANC is large, the beak will be small, resulting in a wider ostium but potentially causing obstruction more inferiorly.

52. ETHMOID BULLA Well pneumatized most constant anterior ethmoid cell 8% rudimentary/ absent Separated posteriorly from ground lamella by retrobullar recess if does not extend upto skull base, suprabullar recess.

53. If both suprabullar and retrobullar recess are absent : semilunar space above and behind the bulla : sinus lateralis Sinus lateralis opens into middle meatus by a cleft : hiatus semilunaris superioris Frontal recess may drain into sinus lateralis

54. FRONTAL RECESS The frontal recess is an hourglass like narrowing between the frontal sinus and the anterior middle meatus through which the frontal sinus drains Bounded anteriorly by agger nasi cell Posteriorly by bulla ethmoidalis Laterally by lamina papyracea Medially by middle turbinate, lateral wall of olfactory fossa .

55. Roof of frontal recess formed by fovea ethmoidalis : thick bone : resistance to injury Anterior ethmoid artery runs across fovea ethmoidalis When ther is a suprabullar recess : ethmoid artery will be in the frontal recess Anterior ethmoidal artery may lie in a mesentry in 15-45% pts, suspended from the skull base.

56. Anatomical variants

57. Fronto-ethmoid/kunh cells/bulla frontalis Are the anterior ethmoid cells which invade the frontal bone, bulging its floor They are more easily demonstrated at saggital view, where they appear as ethmoid air cells located above the ethmoid bulla and as an extension towards the frontal sinus. Depending on their size and pneumatization extent, such cells may affect the frontal sinus drainage. These air cells, are categorized into four types depending on their number and degree of extension into the frontal sinus. They are all located superior to the ANC.

58. Type 1 (most common): Single cell superior to the ANC that does not extend into the frontal sinus Type 2: Two or more cells superior to the ANC that may or may not extend into the frontal sinus. Type 3: Single frontal cell superior to the ANC that extends into the frontal sinus. Type 4: Completely contained in the frontal sinus. This configuration is rare.

59. This is formed by lateral and posterior pneumatization of the most posterior ethmoid cells over the sphenoid sinus. The presence of Onodi cells increases the chance that the optic nerve and / or carotid artery would be exposed in the pneumatized cell.

60. VARIATIONS OF THE CRIBRIFORM PLATE The cribriform plate may present at variable levels and, it is classified according to the criteria developed by Keros . It is based on the height of the olfactory fossa in relation to the roof of the ethmoid sinus as compared with the length of the lateral lamella of cribriform plate. The higher the Keros grade, the greater the chance of injury of the cribriform plate and olfactory fossa .

61. A: Type 1 (lateral cribriform lamella of 1–3 mm, the cribriform plate and the ethmoid cell roof are practically parallel to each other). B: Type 2 (lateral lamella of 4-7 mm, cribriform plate is much below the nasal cavity as compared with the ethmoid roof). C: Type 3 (lateral lamella of cribriform plate of 8–16 mm, ethmoid cell roof is located much above the plate

62. Haller cell Infraorbital ethmoid cells or Haller cells  are ethmoid air cells located anteriorly to the ethmoid bulla, along the orbital floor, adjacent to the natural ostium of the maxillary sinus, which may cause mucociliary drainage obstruction, predisposing to the development of sinusitis.

63. VARIATIONS IN MIDDLE TURBINATE Concha bullosa is a variation originated from pneumatization of the bone plate by extension of ethmoid sinus cells. Such variation may be either uni - or bilateral. Varied degrees of pneumatization of the concha may be observed, possibly causing middle meatus or infundibulum obstruction.

64. PARADOXICAL TURBINATES Paradoxical turbinates occur as the convexity of the middle turbinate is directed towards the medial wall of the maxillary sinus. Depending on the degree of curvature of the paradoxical turbinate compression of the infundibulum and sinusal obstruction may be observed.

65. A)horizontal uncinate b)hypertrophy of lt uncinate . C)pneumatisation of lt uncinate . D)vertical lt uncinate .

66. ACCESSORY MAXILLARY OSTIA Accessory maxillary ostia are generally solitary, but occasionally may be multiple. Easily seen, circular : tunnel like, ovoid Such variation may be congenital or secondary to sinusal diseases. Possible mechanisms involved in the development of such variation include: main ostium obstruction, maxillary sinusitis or anatomical/pathological factors in the middle meatus , resulting in rupture of membranous areas.

67. THANK U