L1 Anatomy Of The Nasal Cavity Flashcards
Parts of external nose ( 3)
Formed by cartilages, bones & fibrous tissue
Bones of external nose (3)
Nasal
Frontal process of the maxillae
Nasal process of Frontal bone
Nerve supply to skin of external nose
Above :
Ophthalmic nerve
a. infratrocheal branch
b. external nasal
Lateral :
Maxillary nerve
a. lateral branch of infraorbital nerve
Arterial supply to external nose
Above :
Ophthalmic artery
a. Dorsal nasal branch
Lateral :
Maxillary artery
a. infraorbital branch
Down:
Branches of facial artery
What can happen In fracture of the cribriform plate of the ethmoid bone?
the CSF may leak into the nasal cavity resulting in (CSF rhinorrhea)
(dribbling of clear fluid from the nose on bleeding and straining)
Structures of nasal cavity (4)
🌕Roof:
anterior —
Types of mucosa in nasal cavity
- Olfactory mucosa
- olfactory nerve that gives bipolar axons that penetrate the cribriform plate of the ethmoidal bone in the anterior part of the roof of the nasal cavity giving receptor cells ( with cilia and dendrites ) surrounded by supporting cells ( epi. cells ) - resp. Mucosa
- similar to rest of resp. tract
Type of cells in the mucosa ( mucosal cells )
🌕Ciliated cells
🌕Brush cells ( with microvilli )
🌕Goblet cells
🌕Small granule cells (Kulchitsky cells) — DNES ( diffused neuroendocrine system)
🌕Basal cells ( stem cells of ciliated and goblet cells )
Respiratory mucosa components (5)
Cilia
Goblet cells
Serous & Mucous glands ( in lamina propria )
High vascularity
Rich nerve supply
Components of the roof of nasal cavity
- Nasal cartilage
- Nasal bone
- Frontal bone
- Cribriform plate of ethmoid bone ( anteriorly )
- Body of the sphenoid bone ( posteriorly )
Nasal cavity is connected to anterior cranial cavity by
- Emissary veins that connect (nasal veins) with ( superior saggital sinus )
- Lymphatics that connects the nasal cavity to the subarchaniod space
Floor of nasal cavity is made of :
- Maxillary bone ( palatine process )
2. Palatine bone ( horizontal process )
Nasal and oral cavity are connected by :
Incisive canals in the incisive fossa in the anterior part of ( nasal cavity floor )
Components of nasal septum
BONES:
- perpendicular process of ethmoidal bone (sup.)
- Vomer (inf.)
- Nasal process of frontal
- Sphenoidal bone
CARTILAGES:
- septal cartilage
- Septal process of ( inferior nasal cartilage )
What is the name of the most anterior part of nasal septum
Columella which os fibro-fatty tissue and mobile
Nerve supply to the nasal septum
🔥Olfactory nerve (in the roof )
🔥Trigeminal nerve
🕸OPHTHALMIC
- external nasal nerve
- anterior ethmoidal nerve
🕸 maxillary
- anterior superior alveolar nerve
- sphenopalatine nerve
- greater palatine nerve
Arterial supply to nasal septum
🕸 ophthalmic artery (sup)
- anterior ethmoidal artery
🕸 maxillary ( lateral )
- sphenopalatine artery
- greater palatine artery
🕸 facial artery (inf )
What is the most affected area that leads to epistaxis ?
Kisselbach’s area which most of arteries anastomoses there
What does the lateral walls of nasal cavity made from?
BONES
- Nasal bones
- frontal process of maxillary bone
- Lacrimal bone
- Labyrinth of ethmoid (giving sup. and mid. conchae )
- Inferior conchae
- Perpendicular plate of the palatine ( with sphenopalatine foramen in its upper part )
- Medial pterygoid of sphenoid
CARTILAGES
- upper and lower nasal cartilages with some other
Most anterior part of lateral nasal walls called ?
It is mobile fibro-fatty tissue called (ala)
What is the Vestibule?
A small depressed area in the anterior part. It is lined by modified skin containing short, stiff curved hairs called vibrissae.
What is the The atrium of the middle meatus ?
It is the middle part just in front of the middle meatus and above the vestibule.
What are the components of the meatuses ?
- Inferior:
- lacrimal duct in the anterior part - Middle :
* frontal air sinuses
* anterior and middle ethmoidal air sinuses
* maxillary air sinuses - Superior:
- posterior ethmoidal air sinuses - Sphenoethmoidal recess:
- sphenoidal air sinuses
What is Fovea ethmoidalis ?
bony plate separating roof the ethmoidal air sinuses from anterior cranial fossa
Nerve supply to lateral walls of nasal cavity
- Olfactory
- Trigeminal
A. Ophthalmic nerve:
- anterior ethmoidal nerve
B. Maxillary
- ptreygopalatine ganglion ( secretomotor )
- branches of greater palatine
- greater palatine
- anterior superior alveolar nerve
Venous drainage from the Lateral wall of the Nasal cavity
drains into facial vein ( in front )
retropharyngeal vein,pterygoidvenous plexus ( behind )
What is the function of Sphenopalatine foramen?
Connects pterygopalatine fossa with nasal cavity. It transmits nerves and vessels ( such as pterygopalatine secretomotor nerve ) from this fossa to the nasal cavity. It is present in the upper part of the perpendicular plate of the palatine bone
Arterial supply to the Lateral wall of the Nasal cavity
- Ophthalmic
- anterior ethmoidal artery - Maxillary
- sphenopalatine artery
- branches of greater palatine
- greater palatine - Facial artery
Where does Maxillary air sinus situated ?
Within the body of maxilla
What are the nerves to the maxillary air sinuses ?
Mainly maxillary nerve
1. Anterior, middle, posterior superior alveolar nerve ( supplying upper tooth in the same time )
- Infra-orbital branch
What are the Structures reducing the openings of the maxillary sinus opening ?
the ethmoid, inferior nasal concha & perpendicular plate of palatine bone
Lymphatic drainage of the nasal cavity
Anterior part –submandibular lymph nodes
Posterior part – retropharyngeal nodes & Upper deep cervical lymph nodes
Roof – drains into CSF
How Infection from nasal cavity & nasopharynx can spread into the middle ear ?
By auditory tube in the lateral walls of nasopharynx
