Week 1: CAI Flashcards
What is the Entrance to Nasopharynx called?
Nasal Choanae
What do the Upper Respiratory and Gastrointestinal Tracts share?
A common proximal pathway
What is Choanal Atresia? Who is it most commonly seen in?
- Compromise in normal size of Nasal Choanae, can be unilateral/bilateral
- Most common in neonates as one of most common cause of nasal obstruction in neonates
What is the separation between the nasal cavity and the oral cavity?
Bone - Hard Palate
What is the Concha
Superior, Middle, and Inferior Concha = Bony shelves that project inferiomedially from lateral wall on both sides of nasal cavity
Create meatuses
What are the nasal cavity meatuses?
Superior, Middle, Inferior Meatus - Spaces under each bony shelf (Concha)
What is the function of the nasal cavity? What structures assist this function?
- Bony Concha have highly vascular mucosal tissue covering: Warms, humidifies, and filters air coming through
- Bony Concha create turbulent air flow through the nasal cavity due to their shape. Further assisting as extending time for air to be warmed and allowing it to trap particle matter as air flows
What do the nasal cavity and paranasal sinuses do to sound?
Produces resonance in our voice
What is a nasal polyp
- Soft, painless, non-cancerous growth on lining of nasal cavity/sinus
- Hang down like teardrops
What causes nasal polyps to form? (5)
- Chronic conditions I.e. Asthma
- Recurrent infections
- Drug Sensitivities
- Allergies
- Immune Disorders
What can Nasal polyps cause?
- Large polyps / groups of polyps can block nasal passages and lead to difficulty breathing
- Large polyps can result in loss of sense of smell
- Polyps can cause recurrent sinus infection as they can block sinus drainage
What comprises the nasal septum?
- Septal Cartilage (most anterior)
- Ethmoid bone (posterior + superior)
- Vomer (bone) (posterior + inferior)
- Hard Palate sits underneath
What bones make up the nasal cavity, not the nasal septum?
- Nasal Bone
- Maxilla
- Palatine
- Inferior Concha
- Superior + Middle Concha (part of Ethmoid bone)
What is the main blood supply to the Nasal Cavity?
- Internal Carotid
* External Carotid
What arteries supply the Nasal Cavity?
- Internal Carotid - Anterior + Posterior ethmoidal arteries
- External Carotid - Maxillary a. + Sphenopalatine a.
- Come together on anterior nasal septum at Little’s Area / Kiesselbach’s Plexus - Rich Anastomoses
What area of the Nasal Anastomoses is the main origin of nosebleeds?
Little’s Area / Kiesselbach’s Plexus
What sensory nerves innervate the nasal cavity? Include their divisions
- Olfactory Nerve (CN I)
- Trigeminal Nerve (CN V) - CN Va (Opthalmic Division) + CN Vb (Maxillary Division)
- Both are Cranial Nerves
Where can CN Va pain refer to/from?
Opthalmic division pain can refer to/from frontal head (forehead)
Where can CN Vb pain refer to/from?
Maxillary division of Trigeminal Nerve pain can refer to/from upper maxillary teeth
What does the Olfactory Nerve sense? CN I
Smell
What does anosmia mean?
Loss of smell
What might a fracture of the cribriform plate result in?
CSF Rhinorrhoea - Leaking of intracerebral fluid through nasal cavity
Anosmia - Loss of smell if olfactory nerve endings damaged
What is the cribriform plate of the nasal cavity?
Found between the nasal cavity and the brain. Bone that separates and where olfactory nerves travel through to innervate nasal cavity region
How does the Nasolacrimal Duct drain into the nasal cavity?
Lacrimal sac - Nasolacrimal duct - Inferior concha - Opening of duct into inferior meatus
What are the parts that make up the Upper Respiratory Tract?
Nares, Nasal Cavity, Nasal Choanae, Nasopharynx
What are the structures making up the Upper Respiratory Tract?
- Superior, Middle, Inferior Concha and Meatuses
- Nasal Septum
- Nasal Cavity
What are the Mucosa Lined Regions of the Nasal Cavity?
- Nasal Vestibule region (Find hairs here, trap large particles)
- Olfactory region (smell)
- Respiratory region (lined with ciliated pseudostratified columnar)
What are the boundaries that make up the upper respiratory tract?
- Hard Palate
- Nasal Choanae
- Cribriform plate?
What are the functions of the Upper respiratory tract?
- Warms
- Humidifies
- Filters
Describe the Sensory Innervation of the nasal cavity and how this relates to pain referral
- Olfactory nerve (CN I)
- Two divisions of Trigeminal Nerve (CN V)
- CN Va (Ophthalmic) - Refers pain to/from Frontal Head
- CN Vb (Maxillary) - Refers pain to/from Upper Maxillary Teeth
What are the potential consequences of a nasal polyp?
- Difficulty Breathing
- Anosmia
- Recurrent infections
- Blocked sinus/nasolacrimal drainage
What are the major arterial branches which supply the nasal cavity, and where do most nosebleeds originate?
- Internal + External Carotids
* Kiesselbach’s Plexus / Little’s Area
A 55 y.o. man presents to A&E and requires insertion of an NG (Nasogastric tube). What is the ORDER of structures the tube will pass through in order to get to the stomach?
Nares - Nasal Cavity - Nasal Choanae - Nasopharynx - Oropharynx - Laryngopharynx - Oesophagus
A 55 y.o. man presents to A&E and requires insertion of an NG (Nasogastric tube). What is the ORDER of structures the tube will pass through in order to get to the stomach?
Nares - Nasal Cavity - Nasal Choanae - Nasopharynx - Oropharynx - Laryngopharynx - Oesophagus
What are the Sinus Cavities?
- 4 Pairs of air filled cavities
- Frontal
- Ethmoid
- Maxillary
- Sphenoid - Quite deep
What is the sensory innervation of the sinuses?
- All, except maxillary sinus, innervated by Ophthalmic division (CN Va) of Trigeminal Nerve
- Maxillary Sinus innervated by Maxillary Division (CN Vb) of Trigeminal Nerve
What sinus regions are innervated by CN Va?
- Ophthalmic Region of Trigeminal nerve
- Frontal
- Ethmoid
- Sphenoid
What sinus regions are innervated by CN Vb?
- Maxillary region of Trigeminal Nerve
* Maxillary sinus
What Sinuses drain into the Sphenoethmoidal recess of the nasal cavity?
Sphenoid Sinus
What Sinuses drain into the Middle Meatus of the nasal cavity?
- Frontal
- Ethmoid
- Maxillary (Upwards)
What Sinuses drain into the Inferior Meatus of the nasal cavity?
- Nasolacrimal
Where in the nasal cavity do the sinuses and ducts drain?
- Sphenoid - Sphenoethmoidal Recess
- Frontal - Middle Meatus
- Ethmoid - Middle Meatus
- Maxillary - Middle Meatus
- Nasolacrimal Duct - Inferior Meatus
How does the Maxillary Sinus drain into the nasal cavity?
- Upwards against gravity
* Via Hiatus Semilunaris
What in the oral cavity has very close relations to the maxillary sinus?
The floor of the maxillary sinus is in close relations to the upper maxillary teeth. Can affect drainage in cases.
What might poor drainage of the maxillary sinus lead to?
- Inflammation
- Infection
- Sinusitis
What issue can arise within the maxillary sinus?
An Extra bony septa that originates from the floor of the maxillary sinus (maxillary tooth) region into the sinus. Can find collections of fluid within the cavities formed
To what surgical relevance is the sphenoid sinus?
- Sphenoid Sinus is closely related to the Cranial Cavity
- Can be used for minimally invasive surgical approaches to the pituitary gland
- Through Nares, Nasal Cavity, Sphenoid Sinus, Can reach Pituitary
What separates the ethmoid sinus and the bony orbit?
Lamina Papyracea
What can occur if there is persistent infections in the ethmoid sinus?
- May erode + Spread infection through Lamina Papyracea into the bony orbit
- Causes Periorbital Cellulitis
Describe the position and routes of drainage of the sinuses and the Nasolacrimal duct
- Sphenoid sinus (superior to superior meatus) - Drains into sphenoethmoidal recess
- Frontal, Ethmoidal, Maxillary sinuses - Drain into Middle Meatus
- Nasolacrimal Duct - Drains into Inferior Meatus
Which Sinus drains against gravity, and why is this clinically relevant?
Maxillary sinus
Poor drainage may result in inflammation, infection, sinusitis
How might an infection in one of the sinuses lead to an infection around the eye (periorbital cellulitis)
Persistent infection in ethmoid sinus may erode through the lamina papyracea, spreading infection into the bony orbit.
What are the paranasal sinuses lined with?
Respiratory epithelium, ciliated pseudostratified columnar epithelium. Produces mucus which need to drain into nasal cavity. If have virus/allergy lining can become inflamed, increasing fluid production
Outline the basic structure of the Ear
- External Acoustic Meatus
- Tympanic membrane
- Middle ear - Pharyngotympanic tube stems off to join nasopharnyx directly here
- Inner ear
- Internal Acoustic Meatus leading CN VIII (Vestibulocochlear) to the Intracranial Cavity
Within which area of the skull does the ear sit within?
Petrous portion of temporal bone - Ear bits protected and embedded
What is the ear divided into?
- External ear
- Middle ear
- Inner ear
What is the sensory innervation of the external ear?
- Auricle/pinna, external auditory meatus, tympanic membrane from both Cranial & Somatic Nerves
- C2 + C3
- CN Vc (3rd division of trigeminal nerve)
- CN VII & CN X (vagus nerve)
What is meant by referred pain?
If same nerve innervates multiple area, if one area that that nerve innervates perceives sensory stimulation, may perceive pain or stimulation is any of the other area that that nerve innervates.
What are the patterns of sensory innervation of the external ear? What does this mean in terms of referred pain?
- Referred pain to the ear can be from:
- CN Vc - Mandible & Mandibular teeth
- CN Vc - Temporomandibular (Jaw) joint (TMJ)
- CN X - Laryngopharynx
- CN X - Larynx
- CN X - Cardiac
What is the Auricle/Pinna made up of?
- Formed of elastic cartilage covered with skin, and a fleshy lobule
- Helix
- Antihelix
- Concha
- Lobule
- Tragus (the goat)
- Antitragus
- External Acoustic Meatus
Describe the function of the structure of the Auricle/Pinna/External Ear?
The shape of the ear captures soundwaves and directs them to the ear. Allows to hear things and localise the direction which they come from
What must you do if a patient presents with an auricle/pinna infection? Why?
- Conduct systematic examination of all nodes in the pericranial cervical line, down jugular and supraclavicular. To check if infection has spread
- Infection can result in abscess formation and spread to local node groups
Describe the External Acoustic Meatus Structure
- Anterioinferior angled tube/passage 2/3 cm long met by tympanic membrane
- S-shaped in an adult
- Laterally Cartilaginous transforms to Bony Medially where it is embedded within the petrous (hard) portion of temporal bone
- Contains modified sweat glands that produce cerumen (wax)
What is inflammation of the EAM called?
Otitis Externa
Describe the sensory innervation of the EAM
- CN Vc - Mandibular division of Trigeminal cranial nerve
- CN X - Vagus cranial nerve
- So if have otitis externa may get referred pain to any area where these nerves innervate
What is an otoscope?
Device through which light is shone and image magnified to inspect the external acoustic meatus and tympanic membrane.
Adult and child ear examined differently.
How do you examine an adult ear? How does this differ from child ear?
- Using an otoscope
- Pull Pinna Posterior + Superiorly in order to straighten EAM and examine
- Pull Pinna Posterior +/- Inferiorly
What anatomical structures compose the external ear, and what nerves innervate this area?
- Formed of elastic cartilage covered with skin and fleshy lobule
- Helix, Antihelix, Concha, Lobule, Tragus, Antitragus, External Acoustic Meatus, Tympanic Membrane
- Nerve innervation = C2 + C3, CN X, CN VII, CN Vc
What are the common areas that pain can refer to / or from the ear?
- CN Vc = TMJ - Temporomandibular join, Mandibular teeth, Mandible
- CN X = Cardiac, Laryngopharnyx, Larynx,