ENT

1. ANATOMY OF NASAL CAVITY
RES EMAN ZAYED
SUPERVISED BY
PROF DR AHMED ALI

2. ANATOMY OF THE NASAL CAVITY

7. • VENOUS DRAINAGE --> ANGULAR --> ANTERIOR
FACIAL--> INTERNAL JUGULAR VEIN

8. ANATOMY OF NASAL CAVITY AND PARANASAL
SINUSES:
- DIVIDED INTO RIGHT AND LEFT NASAL CAVITIES BY NASAL SEPTUM.
- COMMUNICATES WITH THE EXTERIOR THROUGH NOSTRIL AND WITH THE
NASOPHARYNX THROUGH CHOANA.
O EXTERNAL NASAL VALVE: (NASAL VESTIBULE)
- ANTERIOR AND INFERIOR PART OF NASAL CAVITY (NOSTRIL).
- LINED BY SKIN AND CONTAINS SEBACEOUS GLANDS, HAIRFOLLICLES AND
VIBRISSAE.
- FORMED BY:
1. LATERAL CRUS OF LOWER LATERAL CARTILAGE (LLC) .
2. COLUMELLA

9. INTERNAL NASAL VALVE: ( LIMEN NASI ) NARROWEST PART OF NASAL AIRWAY.
- CROSS-SECTION AREA IS 0.73 CM2.
- FORMS AN ANGLE OF 10-15 DEGREE.
- BORDERED BY:
1. SEPTUM
2. ANTERIOR EDGE OF INFERIOR TURBINATE.
3. CAUDAL EDGE OF UPPER LATERAL CARTILAGE (ULC).
LINING MEMBRANES:
- VESTIBULE:
O SKIN KERATINIZED STRATIFIED SQUAMOUS EPITHELIUM.
- LOWER 2/3 OF NASAL CAVITY + PARANASAL SINUSES:
O RESPIRATORY MUCOSA PSEUDOSTRATIFIED CILIATED COLUMNAREPITHELIUM.
- UPPER 1/3 OF NASAL CAVITY:

14. • INFERIOR TURBINATE :
• INFERIOR MEATUS ==> NASOLACRIMAL DUCT
• SUPERIOR TURBINATE ==> SUPERIOR MEATUS => POST ETHMOIDAL
• OLFACTORY EPITHELIUM
• SPHENO-ETHMOIDAL RECESS : MEDIAL SUPERIOR TURBINATE , ANTERIOR TO
SPHENOID

16. • THE MOST ANTERIOR PART OF THE MIDDLE TURBINATE FUSES WITH THE
INFERIORPART OF AGGER NASI TO FORM THE “AXILLA”.
• - MIDDLE MEATUS:
• THE AREA OF THE LATERAL WALL OTHE NASAL CAVITY COVERED MEDIALLY BY
THE MIDDLE
• TURBINATE.
O DRAINS:
1. MAXILLARY SINUS.
2. ANTERIOR ETHMOID SINUS.
3. FRONTAL SINUS.

25. VENOUS DRAINAGE
• VENOUS SYSTEM:
• - ANTERIOR ETHMOID VEIN + POSTERIOR ETHMOID VEIN--> OPHTHALMIC VEIN
• CAVERNOUS SINUS
• - SPHENOPALATINE VEIN --->1- MAXILLARY VEIN -->INTERNAL JUGULAR VEIN
• 2- CAVERNOUS SINUS
• - GREATER PALATINE VEIN--> 1- POSTERIOR FACIAL VEIN --> EXTERNAL
JUGULAR VEIN
• 2- CAVERNOUS SINUS

26. • RETROCOLUMELLAR VEIN:
• - RUNS VERTICALLY DOWNWARDS JUST BEHIND THE COLUMELLA.
• - CROSSES FLOOR OF NOSE AND JOINS VENOUS PLEXUS ON LATERAL NASAL
WALL.
• - COMMON SITE OF VENOUS BLEEDING IN YOUNG PEOPLE.

31. MAXILLARY SINUS
• MAXILLARY SINUS:
• - 1ST SINUS TO DEVELOP IN-UTERO.
• - PRESENT AT BIRTH.
• - BIPHASIC GROWTH:
• 1. BIRTH - 3 YEARS.
• 2. 7 - 18 YEARS OLD.
• - LARGEST PARANASAL SINUS.
• - ADULT VOLUME 15 ML
• - PYRAMIDAL SHAPE OCCUPIES
• BODY OF MAXILLA.
boarders
Anterior wall: Facial surface of
Maxilla.
o Posterior wall: Infratemporal
and Pterygoplatine fossae.
o Medial wall: Uncinate process,
Fontanelles, Inferior Turbinate
o Lateral wall: Zygomatic
Process of Maxilla.
o Roof: Orbital Floor, Infraorbital
nerve and vessels.
o Floor: Alveolar and Palatine
Processes of Maxilla.

32. • OSTIUM:
• O SITUATED HIGH UP IN MEDIAL WALL.
• O OPENS IN POSTERIOR PART OF ETHMOID INFUNDIBULUM INTO MIDDLE MEATUS.
O IT IS ORIENTATED SLIGHTLY OFF SET FROM THE PARASAGITTAL PLANEFACING
POSTERIORLY AND IS USUALLY AROUND 5MM IN DIAMETER.
• O ACCESSORY OSTIUM PRESENT IN 25% MAINLY IN POSTERIOR NASALFONTANELLE,
POSTERO-INFERIOR TO NATURAL OSTIA.
- BLOOD SUPPLY:
1. MAXILLARY ARTERY + FACIAL ARTERY
2. MAXILLARY VEIN
- INNERVATION:
1. INFRAORBITAL NERVE (V2).
- RADIOLOGY:
1. 1ST RADIOLOGIC EVIDENCE AT AGE OF 4-5 MONTHS.

33. ETHMOIDAL SINUS
• ETHMOID SINUS:
- 2ND SINUS TO DEVELOP IN-UTERO.
- PRESENT AT BIRTH (3-4 ANTERIOR ETHMOID CELLS).
- MOST DEVELOPED SINUS AT BIRTH.
- THIN-WALLED AIR CAVITIES OCCUPIES LATERAL MASSES OF ETHMOID BONE.
- BASAL LAMELLA OF MIDDLE TURBINATE DIVIDES IT INTO ANTERIOR AND POSTERIOR GROUP.
• - ADULT SIZE: 10-15 AIR CELLS.
• - ADULT VOLUME: 2-3 ML.
- FORMED FROM 5 BASAL LAMELLA: (RELATIVELY CONSTANT LANDMARKS)
1. BASAL LAMELLA OF UNCINATE PROCESS.
2. BASAL LAMELLA OF ETHMOID BULLA.
3. BASAL LAMELLA OF MIDDLE TURBINATE.
4. BASAL LAMELLA OF SUPERIOR TURBINATE.
5. ANTERIOR WALL OF SPHENOID SINUS.

34. • ROOF IS FORMED BY:
O LATERAL LAMELLA AND FOVEA ETHMOIDALIS MEDIALLY.
O ORBITAL PLATE OF THE FRONTAL BONE LATERALLY , SEPARATED FROM ORBIT LATERALLY BY
LAMINA PAPYRECEA.
- OPTIC NERVE FORMS CLOSE RELATION WITH POSTERIOR ETHMOID CELLS.
- ANTERIOR CELLS DRAINS INTO --> INFUNDIBULM INTO MIDDLE MEATUS.
- POSTERIOR CELLS DRAINS INTO--> SUPERIOR MEATUS.
- BLOOD SUPPLY:
1. ANTERIOR ETHMOID + POSTERIOR ETHMOID ARTERY.
2. MAXILLARY + ETHMOID VEINS (CAVERNOUS SINUS).
- INNERVATION:
1. ANTERIOR ETHMOID + POSTERIOR ETHMOID NERVES. (V1)
• - RADIOLOGY:
1. 1ST RADIOLOGIC EVIDENCE AT AGE OF 1 YEAR.
2. LATERAL VIEW.
3. OCCIPTO-FRONTAL CALDWELL VIEW.

35. FRONTAL SINUS
- NOT PRESENT AT BIRTH.
• - INVADE FRONTAL BONE AT AGE OF 4 YEARS.
- BETWEEN OUTER AND INNER TABLE OF FRONTAL BONE.
- RATIO OF TABLE THICKNESS BETWEEN OUTER AND INNER TABLE IS 2:1
- ADULT VOLUME: 2-3 ML AT AGE OF 12-12 YEARS.
- UNDERDEVELOPED IN 5%
- USUALLY 2 ASYMMETRIC FRONTAL SINUSES SEPARATED BY THIN SEPTUM.
- OSTIUM LOCATED POSTERO-MEDIALLY IN THE FLOOR.

36. • DRAINAGE DEPENDS ON SUPERIOR ATTACHMENT OF UNCINATE PROCESS:
1. ATTACHES TO LAMINA PAPRYCHEA (MOST COMMON):
DRAINS INTO MIDDLE MEATUS MEDIAL TO ETHMOIDAL INFUNBIDULUM (BETWEEN
UNCINATE PROCESS AND MIDDLE TURBINATE )
2. ATTACHES TO ETHMOID ROOF (SKULL BASE):
DRAINS INTO ETHMOIDAL INFUNDIBULUM.
3. ATTACHES TO MIDDLE TURBINATE:
DRAINS INTO ETHMOIDAL INFUNDIBULUM.

37. RELATIONS:
O ANTERIOR WALL: SKIN OVER FORHEAD
O POSTERIOR WALL: MENINGES AND FRONTAL LOBE.
O FLOOR: ORBIT.
- BLOOD SUPPLY:
O SUPRAORBITAL + SUPRATROCHLEAR ARTERY
O OPHTHALMIC (CAVERNOUS SINUS) + SUPRAORBITAL (ANTERIOR FACIAL) VEINS.
- INNERVATION:
O SUPRAORBITAL + SUPRATROCHLEAR NERVES (V1)
- RADIOLOGY:
O 1ST RADIOLOGIC EVIDENCE AT AGE OF 6 YEAR.
O LATERAL VIEW.
O OCCIPTO-FRONTAL CALDWELL VIEW.

38. SPHENOID SINUS
• SPHENOID SINUS:
- NOT PRESENT AT BIRTH.
- OCCUPIES BODY OF SPHENOID.
- USUALLY 2 ASYMMETRIC SINUSES SEPARATED BY THIN SEPTUM.
- REACH SELLA TURCICA BY AGE OF 7 YEARS.
- ADULT SIZE AT 12-18 YEARS
- ADULT VOLUME: 0.5-8 ML.
- OSTIUM:
O SITUATED IN UPPER PART OF FACE OF SPHENOID AT THE LEVEL OF INFERIOR ONE THIRD OF THE SUPERIOR
TURBINATE AND ALONG A HORIZONTAL PLANE
THROUGH FLOOR OF THE ORBIT.
O LOCATED MEDIAL TO POSTERIOR END OF SUPERIOR TURBINATE IN 80% AND LATERALLY IN 20%.

39. • ANATOMICAL RELATIONSHIPS OF SPHENOID OSTIUM:
O 30 DEGREE FROM NASAL CAVITY FLOOR. (MOST RELIABLE)
O ADJACENT TO POSTERIOR BORDER OF NASAL SEPTUM.
O 6-8 CM POSTERIOR TO ANTERIOR NASAL SPINE.
O 1.5 CM ABOVE CHOANAL FLOOR
O 1/3 UP FROM CHOANA TO SKULL BASE.
- RELATIONS:
O ROOF: PITUITARY GLAND, OPTIC CHIASM.
O FLOOR: NASOPHARYNX, PTERYGOID CANAL.
O MEDIAL: OTHER SPHENOID BONE
O LATERAL WALL: CAVERNOUS SINUS, INTERNAL CAROTID ARTERY, CN- II, III, IV, V1, V2, AND VI

40. • ANTERIOR WALL OF SPHENOID (FACE OF SPHENOID) IS OFTEN THIN AND IS CROSSED
INFERIORLY BY THE POSTERIOR NASAL ARTERY (SEPTAL BRANCH OF
THESPHENOPALATINE ARTERY).
- BLOOD SUPPLY:
O SPHENOPALATINE ARTERY.
O MAXILLARY VEIN.
- INNERVATION:
O SPHENOPALATINE NERVE.
- RADIOLOGY:
O 1ST RADIOLOGIC EVIDENCE AT AGE OF 6 YEAR.
O LATERAL VIEW.