Lec1. Anatomy of Nasal Cavity & Paranasal Sinuses PDF

1 DR/ABDELHAMID 2 DR/ABDELHAMID 3 DR/ABDELHAMID ILOS 1-By the end of this lecture, the student should be able to list the: Paranasal sinuses &their clinical importance. 2- Be able to describe the nasal cavity regards: Openings Walls Features of the lateral wall Arterial &nerve supply Clinical...

1 DR/ABDELHAMID 2 DR/ABDELHAMID 3 DR/ABDELHAMID ILOS 1-By the end of this lecture, the student should be able to list the: Paranasal sinuses &their clinical importance. 2- Be able to describe the nasal cavity regards: Openings Walls Features of the lateral wall Arterial &nerve supply Clinical points 4 DR/ABDELHAMID PARANASAL SINUSES 5 DR/ABDELHAMID PARANASAL SINUSES 6 DR/ABDELHAMID SPHENOIDAL AIR SINUS 7 DR/ABDELHAMID PARANASAL SINUSES 1. Definition: They are air-filled spaces in certain bones which surround the nasal cavity. They open into the lateral wall of the nose. 2.Functions: Warming & humidifying the inspired air. Diminishing the weight of the skull. They add resonance to the voice. 8 DR/ABDELHAMID LIST OF PARANASAL SINUSES 1-Maxillary sinus -------- Inside the body of the maxilla. 2-Frontal sinus --------- Between the two plates of the frontal bone. 3-Sphenoidal sinus ------------ Inside the body of the sphenoid bone. 4-Ethmoidal sinuses----------inside the ethmoidal labyrinth (Anterior, middle & posterior ethmoidal groups) - All the sinuses are present at birth except the frontal sinus appears during the 2nd.year of life 9 DR/ABDELHAMID Nose - The nose is the organ of breathing (cleans, warms, and moistens the inspired air) in addition to its olfactory function. 10 DR/ABDELHAMID NOSE 11 DR/ABDELHAMID Nasal Cavity - The cavity of the nose is subdivided into right and left halves by the nasal septum. - The two halves open anteriorly on the face through the anterior nares (nostrils), and open posteriorly into the nasopharynx through the posterior nasal apertures (choanae). 12 DR/ABDELHAMID ANT. NARES (NOSTRILS) 13 DR/ABDELHAMID Choanae 14 DR/ABDELHAMID Bony skeleton of the nasal cavity is formed of: (roof,floor,lateral wall &nasal septum) I. Roof is formed by: - Anterior part------ Nasal process of the frontal bone + Nasal bone. - Middle part ------- Cribriform plate of the ethmoid bone. - Posterior part---- Body of the sphenoid bone. 15 DR/ABDELHAMID Roof, floor & nasal septum 16 DR/ABDELHAMID II. Floor is formed by: - Anteriorly: Palatine process of the maxilla. - Posteriorly by: the palatine bone. 17 DR/ABDELHAMID III. Medial wall (nasal septum) is formed by: - Postero-inferior---------- Vomer. - Superiorly ------------ Perpendicular plate of the ethmoid bone. - Antero-inferior ------- Septal cartilage. 18 DR/ABDELHAMID IV.The lateral wall of the nose is subdivided into two areas which are: 1.Vestibule: Lies immediately above the nostril and lined with skin containing hair (nasal vibrissae). 2.Area of Nasal conchae and meatuses: 19 DR/ABDELHAMID LATERAL WALL OF NASAL CAVITY Superior concha Superior meatus Middle concha Middle meatus vestibule inferior concha Inferior meatus 20 DR/ABDELHAMID BONES FORMING LATERAL WALL OF NOSE 21 DR/ABDELHAMID OPENINGS IN LATERAL WALL OF NASAL CAVITY 22 DR/ABDELHAMID OPENINGS IN LATERAL WALL OF NASAL CAVITY ????? 23 DR/ABDELHAMID 1. Conchae - They are bony plates covered with mucous membrane. - They are three (superior, middle & inferior nasal conchae). 24 DR/ABDELHAMID 2. Meatuses - They are depressions below each concha (superior, middle & inferior meatuses). 1.Superior meatus: - It receives the opening of posterior ethmoidal air sinus. 25 DR/ABDELHAMID 2.Middle meatus: - It receives the openings of the following sinuses: i. Frontal air sinus. ii. Anterior&middle ethmoial air sinuses. iii. Maxillary air sinus. 26 DR/ABDELHAMID 3. Inferior meatus - It receives the nasolacrimal duct. 27 DR/ABDELHAMID Spheno-ethmoidal recess: - It is a triangular fossa between the superior concha and the roof of the nose. - It receives the opening of the sphenoidal air sinus 28 DR/ABDELHAMID Arterial blood supply of nose MAXILLARY ARTERY - It is a branch from the EXTERNAL CAROTID ARTERY 29 DR/ABDELHAMID External carotid artery 30 DR/ABDELHAMID 31 DR/ABDELHAMID Nerve supply of nose: 1. Olfactory area (1 cm) --- Olfactory nerves. (this area includes the roof and upper parts of both the septum and lateral nasal walls) 2- Respiratory area ----maxillary nerve (part of trigeminal nerve). 32 DR/ABDELHAMID OLFACTORY MUCOSA Olfactory mucosa 33 DR/ABDELHAMID NERVE SUPPLY OF NOSE Olfactory nerve Maxillary nerve 34 DR/ABDELHAMID 35 DR/ABDELHAMID