Nose Flashcards
Give four roles of the nose
- Warms and humidifies
- Removes and traps pathogens
- Responsible for smell
- Drains and clears Paranasal sinuses and lacrimal ducrs
Describe the anatomy of the nose
Root - as it joins forehead Bridge - top of the nose Dorsum Nasi Nares - Nostrils Apex - between nostrils Ala - side of nostrils
Name two bones in the external nose
Nasal Bone (ethmoid) Maxilla
Name four cartilages associated with the external nose
Septal
Lateral
Major Alar
Minor Alar
Describe the blood supply to the external nose
Facial Artery (Angular and Lateral Nasal) Branches of Maxillary and Opthalmic
The external nose is drained by the facial vein. Why is this relevant?
Valveless structure that runs into opthalmic and then cavernous sinus so infection in this region can cause intracranial spread (danger triangle)
What are the three regions of the nasal cavity?
Area surrounding external opening - Vestibule
Respiratory region
Olfactory region
What are conchae/turbinates?
Bony shelves protruding into cavity (superior, middle and inferior)
Increase SA of cavity and slows air flow down
What are meatuses?
4 Pathways between conchae
Inferior - between inferior conchae and floor
Middle - between inferior and middle conchae
Superior - between middle and superior conchae
Sphenoethmoidal - Superoposterior to superior
What structures open up into middle meatus?
Frontal, Maxillary and Ethmoid Sinuses
What structures open up into inferior meatus?
Nasolacrimal duct
Eustacian tube
What are two gateways of the nasal cavity?
Cribriform plate - into Ethmoid bone
Sphenopalantine - Between nasal cavity and Pterygopalantine fossa
The vasculature of the nasal cavity has to be rich. Describe this
Internal Carotid - Anterior and Posterior Ethmoidal (branches of opthalmic through cribriform plate)
External Carotid - Sphenopalantine, Greater Palantine, Superior Labial, Lateral Nasal
Anastamose in Little’s Area
Describe the innervation of the nasal cavity
Special Sensory - Olfactory
General Sensory - Nasociliary (Opthalmic) and Nasopalantine (Maxillary)
How would a Cribriform plate fracture present?
CSF Rhinorrhoea
Anosmia
What are Paranasal Sinuses?
Air filled extensions of nasal cavity, lined with pseudostratified epithelium and interspersed with goblet cells
Name four roles of Paranasal SInuses
Reduce weight of head
Supports immune defence
Humidifies inspired air
Increases vocal resonance
Describe the anatomy of the Frontal Sinus
Triangular shaped within the frontal bone
Drainage into middle meatus
Sensation by Supraorbital (CNV1)
Describe the anatomy of the Ethmoidal Sinus
Made up of three
Anterior - into middle meatus
Middle - into middle meatus
Inferior - into superior meatus
Describe the anatomy of the Maxillary Sinus
Drains into middle meatus (just below frontal so fluid can enter maxillary)
Maxillary nerve also supplies teeth - referred toothache
Give three broad causes of Nasal Obstruction
Anatomical
Nasal lining
Autonomic
Name three anatomical causes of nasal obstruction
Septal Deflection
Adenoidal Hypertrophy
Chonal Atresia
Chonal Atresia is a part of CHARGE Syndrome. How would it present?
Unilateral - persistent nasal drainage, recurrent sinus infections
Bilateral - RDS or Cyanosis
Name two nasal lining causes of nasal obstruction
Rhinitis
Nasal Polyps
Name an autonomic cause of nasal obstruction
Vasomotor Rhinitis (increased parasympathetic flow causes engorgement)
Nasal discharge has two different terms, what are they?
Rhinorrhoea - out of nostrils
Catarrh - Post nasal drip
Give two causes of watery nasal discharge
Allergic
CSF
Give two causes of mucopurulent nasal discharge
Bacterial Rhinitis
Foreign Body
Give two causes of serosanguinous nasal discharge
Neoplasia
Give two causes of bloody nasal discharge
Trauma
Neoplasia
How do allergies to dust mites present?
Sneezing upon waking (bed acts as resevoir)
What is Cacosmia?
Unpleasant smell detected mainly by others
Indicated nasal sepsis
Name two nasal causes of Halitosis
Chronic Sinusitis
Post Nasal Drip
Describe the pathophysiology of Allergic Rhinitis
IgE mediated inflammation of nasal mucosa due to mast cell degranulation
Describe the acute and late response of Allergic Rhinitis
Acute - Stimulation of afferent nerves (sneezing), Increase in nasal secretions 15-20 mins later
Late - 6 to 12h later nasal obstruction
Other than sneezing and nasal obstruction, name two features of Alllergic Rhinitis
Mouth Breathing
Halitosis
Allergic Rhinitis may require further investigation to determine allergen. What would these be?
Skin Prick Test (note - surpressed by antihistamines, steroids and TCAs) Blood IgE (useful if patient is on antihistamines
Name some general advice for pollen allergy
Avoid exposure to open grassy spaces
Keep windows shut
Regular servicing of car pollen filter
Name some general advice for house dust mite allergy
Special bedding
Soft toys off of bed
Wash bedding weekly
Laminate>carpet
Describe the possibly medical managements for allergic rhinitis
1) Topical Antihistamines for symptom relief and oral for prevention
2) Nasal Corticosteroids
3) Consider using Corticosteroid and Antihistamine combination (Dimysta) or adding LTRA
4) Short course of oral steroids
Increasing immunological tolerance? Nasal Douching with Saline? Avoiding allergens
Describe a possible surgical management for allergic rhinitis
Reduce inferior turbinates to improve airways
Vasomotor Rhinitis presents similarly to allergic but without the positive test. Describe the pathophysiology
Imbalance in sympathetic and parasympathetic, increasing vascularity and secretions
Causes - Humidity, temperature, pregnancy, alcohol