A: Frontal sinus
B: ethmoid air cells
C: sphenoid air sinus /opening of
D: maxillary air sinus (opening of)
E: frontonasal duct
F: semi lunar hiatus
What are paranasal air sinuses? List the 4.
Air-filled extensions connected by small openings to nasal cavity. Sinus mucosa helps warm and humidify air. They lighten skull and enhance resonance. Frontal, ethmoid, sphenoid and maxillary air sinuses.
A: septal cartilage
B: perpendicular plate of ethmoid
What are the two openings in the eye, and where do they drain to?
Lacrimal puncta and canalicui, drain to larcrimal sac -> to nasolacrimal duct
Where is the pharyngotympanic tube and what does it do?
From tympanic cavity to nasopharynx, lined mucus membrane, equalises pressure either side of tympanic membrane, opened wider by palatine muscles - yawn/swallow. Can get blocked/swell.
Label A and B in this coronal CT scan.
A: maxillary sinus
B: ethmoid sinus
What spinal level does the common carotid split, and to what?
C4, internal carotid (doesn't branch until brain) and external carotid (superior thyroid, ascending pharygeal, lingual, facial, occipital, maxillary, vertebral etc. branches)
What are the 5 soures of the arterial supply of the medial and lateral walls of the nasal cavity?
Where do they all anastamose?
What is epistaxis?
1. and 2. Anterior and posterior ethmoidal arteries (from the opthalmic artery)
3. and 4. Sphenopalatine and greater palatine artery (from maxillary artery)
5. Septal branch of superior labial artery (from facial artery)
The kisselbach area (most common for nose bleeds)
Bleeding from the nose
What is does this CT show?
Sinusitis - mucus accumulation. May have toothache and frontal facial pain.
1: frontal sinus
2: ethmoid sinus
3: sphenoidal sinus
4: maxillary sinus
A: soft palate
C: Palatine tonsil
F: posterior wall of oropharynx
Label Waldeyer's ring, A-D.
B: tubal tonsil
C: palatine tonsil
D: lingual tonsil
What are tonsils?
What is tonsilitis? Describe what you would see.
Tonsil inflammation, see white spots of exudate.
Label the parts of the pharynx
How many pharynx muscles are there?
What is the nerve supply to the pharynx?
What is sensory and motor to the pharynx?
What reflex is involved with the pharynx?
3 constrictors, 3 internal
Sensory IX, motor X
Label the parts of the larynx, A-G
A: hyoid: C3, free-floating bone, anchoring point
B: thyroid cartilage
C: laryngeal prominance
D: cricoid cartilage - C6, only cartilage forming complete ring around trachea
E: thyroid isthmus
F: tracheal rings
G: thyroid gland
Label the facia of the neck, A-D
What structures does B contain?
A: pretracheal fascia
B: carotid sheath
C: Prevertebral fascia
D: deep investing fascia
E: retropharyngeal space (between PTF and PVF)
common carotid artery, internal jugular vein, vagus nerve (VIC)
Describe the different cartilages of the larynx
9 in total, 3 paired (epiglottis, thyroid, and cricoid), and 3 unpaired.
Label A-C of the larynx during rest
A: vestibular fold - choking reflex
B: Rima glottidis - aperture
C: vocal fold - contain vocal ligament and vocalis muscle
Discriminate between extrinsic and intrinsic laryngeal muscles.
What innervates the intrinsic muscles?
What effect do ab/ductors and sphincters/relaxers have on the larynx?
Extrinsic: infra and suprahyroid
Intrinsic: move laryngeal components
Intrinsic all innervated by recurrant laryngeal nerve except cricothyroid (tensor, pulls thyroid cartilage down so increases pitch) which is by superior laryngeal nerve.
Ab/ductors open/close rima glottidis by rotating arytenoids
Sphincters/relaxers lower pitch (pull arytenoids anteriorly)
What does the cricothyroid muscle do?
Increases length and tension of vocal folds = increases pitch.
Describe laryngeal innervation.
CNX splits to recurrant and superior laryngeal nerves.
The RLN responsible for voice and motor to intrinsic muscles, sensory to infraglottic cavity. Left = loops under aortic arch, Right = loops under R. subclavian artery
The SLN branches to internal and external laryngeal nerves.
ILN: sensation, cough reflex
ELN: motor, cricothyroideus, higher pitch
What would happen if:
a) superior laryngeal nerve injury? e.g. compressed or damaged
b) recurrant laryngeal nerve injury?
a) if compressed = goitre, if damaged = thyroidectomy, non gag reflex, monotonous
b) progressive lesions or thyroidectomy causes hoarseness, unilateral paralysis of vocal fold, lateral deviation of normal vocal fold
Why is intubation important?
What happens if there is an airway obstruction?
In trachea, protection against aspiration and gastric insufflation, effective ventilation and O2, anasthetic delivery via ETT
Foreign object in vestibule -> laryngeal muscles spasm -> rima glottidis closes -> air still in lungs - heimlich manoevure. Poss emg cricothyroidectomy