Nose Flashcards
What are teh fucntions of the nose and nasal cavity
Sense of smell
Provides a route for inspired air
Filters inspired air- trapping particles in nasal hair or mucous
Moistens (humidifies) and warms inspired air
Resonating chamber for speech - eg changes when have a cold voice changes
Describe the external nose
Ss
Why is the nasal bone psusceptible to fracture
Nasal bone very commonly fractured
At first very swollen. Send hoe with pan killers. Bring back in a week to review shape of nose when swelling has gone down. Concern if there is an obstruction to breathing through both nostrils.
What is a vestibule
Vestibule is lined with skin containing sebaceous/ sweat glands and hair
Inspired air enters via vestibule (of external nose)
Assists in filtering of inspired air- trapping particles in nasal hair
Hair is important for fi2ltering of hair before it enters nasal cavity???
What are the brounaris of the nasa cavity
Floor: hard palate
Medial wall: nasal septum
Lateral: irregular…
Roof: sphenoid bone, ethmoid bone, frontal bone, nasal bone
What are the concha
Lateral wall is Irregular Due to Presence of Bony Projections Bony projections (conchae) • Superior • Middle • Inferior
- Slows airflow by causing turbulence of airflow
- Increases surface area over which air passes
Shelf like protections - have meatuses underneath them
Increase teh SA over which air will pass.
How will the speed of air chanegs as it passes though
Air going from small space to big - speed will slow down - as it goes from vestibule to proper nasal cavity. CSA gets bigger, as it reaches back of cavity - gets narrow there so speed pickes up
Mucosa will help to filter and moisten the air. Allows time to modify the air befor it exits into nasopharynx
Why are there openings under the meatuses
- Openings under the meatuses allow for drainage of
- Paranasal air sinuses into nasal cavity
- Nasolacrimal duct into nasal cavity
Describe the osteology
Ss
Describe the nasa septum
2 halves separated by septalcartilage - gives scaffolding to shape of bone . Punch to the face - can fracture nasal bone but an also bent/bake theseptal cartilage
What is a septal haematoma
• Cartilage of nasal septum receives blood supply from overlying perichondrium
• Injury to nose can buckle septum and shears blood vessels
• Blood accumulates sub perichondrium..depriving underlying cartilage of its blood supply
• Septal Haematoma
Bleeding occurs between cartilage and overlying perichondrium. Can lead to avascular necrosis. Can share and not heal very well
What is a saddle nose deformity
• Untreated septal haematoma leads to
avascular necrosis of cartilaginous septum
– saddling of nasal dorsum - saddle nose deformity)
• Can also develop infection in the collecting haematoma
– Septal abscess formation further increases likelihood of avascular necrosis of septum
Always examine for septal haematomas in patients presenting with nasal injury
Need to drain the blood - then need to tamponade perichondrium against the cartilage.
Can also be an are for bacteria to collect - reason to drain it åç
Describe the innervation to the nasa cavity
CN v ss
Describe teh mucous membranes
• specialised Olfactory mucous membrane housing olfactory receptor neurones – Olfaction (smell): CN I • Respiratory mucous membrane – Pseudostratified columnar ciliated epithelium rich in goblet cells – Filters (mucous/cilia - Mucocilliary escalatory - waft it) – Humidifies (watery secretions) – Warms (rich blood supply)
What is a nasal polym ad what are the symptoms
• Usually bilateral: common (>40 years)
• Pale or yellow in appearance/fleshy and reddened, Not very tender
• Symptoms include
– Blocked nose and watery rhinorrhoea – Post-nasal drip
– Decreased smell and reduced taste
– Unilateral polyp +/- blood-tinged secretion may suggest tumour
- snorting due to obstruction of air flow
Can drip - chronic runny nose. Can run down the back - tickle - chronic cough