Flashcards in ENT Nasal Anatomy Deck (29):
What are the functions of the nasal cavity?
Allows air to enter the respiratory tract
Warms and Humidifies air
Filters air from dirt
Sense of smell
What is the difference between the nostril and the ala?
Nostril = hole in nose through which air is inspired
Ala = skin that makes up the nostril
What nerve innervates the nasal dorsum/bridge?
Which bones make up the nose?
Nasal Processes = Frontal and Maxillary Bones
Dorsum = Paired Nasal Bones
Septum = Ethmoid and Vomer Bones
Inferior Conchae = Inferior Concha Bones
Superior and Middle Conchae = Ethmoid Bone
What is the main nasal bone?
The Ethmoid Bone
Forms Parts of the Roof, Lateral Walls and Septum of the Nasal Cavity
What does the central part of the Ethmoid Bone contain?
What does the bilateral parts of the Ethmoid Bone contain?
Which fractures can disrupt the Cribriform Plate and Paranasal Sinuses?
Le Fort II and III Fractures
Can cause Anosmia (However, may only be temporary)
Which fractures can cause CSF leakage through the nose?
What kind of epithelium lines the nasal vestibule?
What kind of epithelium lines the majority of the nasal cavity?
What kind of epithelium lines the olfactory region of the nasal cavity?
What is the Olfactory Pathway?
1. Receptor Cells of CN I line the Cribriform Plate, through the Olfactory Epithelium
2. They pass Stimulatory Signals through the Cribriform Plate
3. CN I then Synapse with the Olfactory Bulb (Ganglion)
4. Neurons then pass along the Olfactory Tract to the Temporal Lobe and Other Areas
Which nerves provide somatic sensory innervation of the nasal cavity?
CN V1 via the Nasocillary Nerve (Superior Diagonal Portion)
CN V2 via the Nasopalatine Nerve (Inferior Diagonal Portion)
What is the blood supply to the nasal cavity?
Anterior Ethmoidal Artery (from the Internal Carotid)
Maxillary and Superior Labral Arteries (from External Carotid)
What area of anastomosis is particularly susceptible to nose bleeds?
Kisselbach's (Little's) Area
Rupture or Blow to the Nose in this Area can rupture the Arteries, resulting in Epitaxis.
What is the difference between Conchae and Turbinate?
Conchae = bony projection from the lateral nasal wall
Turbinate = conchae covered with mucosa
What is the function of the Turbinates?
Ruin air flow allowing circulation of air in the nasal cavity for humidification
What are the Nasal Meatuses?
Gaps in the nasal lateral walls, which present above and below the turbinates.
What are the 4 nasal meatuses and where are they found?
1. Sphenoethmoidal Recess (above superior nasal concha)
2. Superior Meatus (below superior concha but above middle concha)
3. Middle Meatus (below the middle concha but above the inferior concha)
4. Inferior Meatus (below the inferior concha)
What does each meatus drain?
1. Sphenoethmoidal Recess drains contents of the Sphenoid Sinus
2. Superior Meatus drains contents from the Posterior Ethmoidal Air Cells
3. Middle Meatus drains contents from the Frontal, Maxillary and Anterior Ethmoid Air Cell Sinuses
4. Inferior Meatus drains contents from the Nasolacrimal Duct
All Meatuses drain into their respective superior conchae
Where is contents from the Middle Ethmoidal Air Cells drained?
What can happen to the nasal airflow with drainage?
Engorgement of the Nasal Mucosa.
One side of the Septum will be Engorged and then it will change to the Other Side, every 3-5 hours. Each Concha is Erectile and thickens and thins from One Side of the Nasal Cavity to the Other.
What are the 4 Paranasal Sinuses?
1. Frontal Sinuses
2. Ethmoidal Air Cell Sinuses
3. Maxillary Sinuses
4. Sphenoid Sinuses
What epithelium does each paranasal sinus contain?
Thin, Respiratory Epithelium
Which paranasal sinus is most susceptible to infection?
Maxillary Sinuses (have to work against gravity for drainage)
Which paranasal sinus can act as a buffer to direct facial trauma?
Which nerves can refer pain to the teeth?