H&N 8: Larynx Flashcards
1
Q
Where is larynx?
A
- lies ant. to laryngeal part of pharynx
- ## extends from base of tongue (C3) to trachea (C6)
2
Q
Where does laryngeal inlet lie?
A
immediately behind post. 1/3 of tongue
3
Q
What is function of larynx?
A
- air passageway linking pharynx with trachea
- as sphincter to prevent food entering trachea
- organ of phonation as can control flow of air coming out of larynx
- also closes vocal folds during swallowing
4
Q
What are walls of pharynx supported by?
A
series of cartilages
5
Q
List the cartilages
A
- large unpaired:
- thyroid
- cricoid
- epiglottis
- small paired:
- arytenoid
- cuneiform
- corniculate
6
Q
What is thyroid cartilage?
A
- largest + consists of 2 plates joined ant. in midline
- males: union gives acute angle (Adam’s apple)
- females: union more obtuse
7
Q
What is cricoid cartilage?
A
- sits immediately below thyroid cartilage at level of C6
- shaped like signet ring - thin band with quad plate which faces post.
- only cartilage which completely encircles larynx
8
Q
What is epiglottis?
A
- fibroelastic leaf-shaped cartilage with stem anchored into angle of thyroid laminae
- oriented upwards + backwards lying behind hyoid + reaching post. surface of tongue
9
Q
What are the arytenoid cartilages?
A
- pyramid shaped - lie on post. lamina of cricoid + art with it in synovial joint
- ## provide attachment for vocal process
10
Q
What are the corniculate cartilages?
A
- sit atop apices of arytenoid cartilages, extending their length
11
Q
What are the cuneiform cartilages?
A
sit in aryepiglottic folds
12
Q
What connects thyroid + cricoid cartilages?
A
- synovial joint
- movement at this joint involved in movement of larynx + change length + tension of VF
13
Q
What attaches thyroid cartilage to hyoid?
A
- thyroid mem + triciteal cartilage
14
Q
What connects arytenoid + cricoid cartilages?
A
- synovial joint - movement can change distance between vocal folds - allow air in + out
15
Q
What is sig about laryngeal ventricles?
A
small as humans don’t need to make really loud noises
16
Q
What is sig about vocal folds?
A
- don’t have blood supply
- glands in laryngeal vent put fluid across them to keep them healthy
17
Q
What is within vocal fold?
A
- vocalis muscle - can change tension within vocal folds + size of rima glottidis
- also open + close vocal folds
18
Q
What is glottis?
A
both vocal folds
19
Q
What is rima glottidis?
A
opening between vocal folds
20
Q
What is thyroid mem?
A
- fibroelastic sheet joining inf. surface of hyoid to sup. aspect of thyroid cartilage
- lat. borders free + thickened + may devolve nodule of cartilage
21
Q
What are the vocal lig?`
A
thick bands of elastic fibres running from vocal processes of arytenoid to thyroid cartilage + covered by mucous mem (vocal folds)
22
Q
What are the vestibular lig?
A
- 2 bands of fibres run from lat. borders of arytenoid cartilages to int. lamina of thyroid cartilage
- run above vocal lig + also covered by mucous mem - vestibular folds (false vocal folds)
23
Q
What are the aryepiglottic lig?
A
pass upwards from apices of arytenoid cartilages to lat. border
24
Q
What is the quadrangular mem?
A
thin fibroelastic sheet filling space between aryepiglottic lig. + vent. lig
25
What is cricothyroid mem?
fibroelastic sheet filling space between vocal folds + cricoid cartilage (conus elasticus - lat. portion)
26
What are extrinsic muscles?
- supra + infrahyoid muscles
- insert into larynx/hyoid bone
- move larynx up/down
27
What is function of mylohyoid + ant. belly of digastric?
raise hyoid + also raise whole of larynx due to thyrohyoid mem
28
What is function of omohyoid + sternohyoid?
lower hyoid so whole of larynx moves down
29
What must the hyoid do?
move larynx out of the way during swallowing + goes into oesophagus
30
What are the intrinsic muscles?
both originate + insert into laryngeal cartilages
31
What is function of cricothyroid muscle?
- moves synovial joint between cricoid + thyroid cartilages
| - change length of VF
32
List functions of intrinsic muscles
- Open the rima to allow passage of air in or out.
- Close the vestibule + rima glottidis during swallowing to prevent aspiration of food.
- Control of tension in the vocal folds for phonation.
33
List intrinsic muscles
1. Posterior cricoarytenoid
2. Lateral cricoarytenoid
3. Transverse cricoarytenoid
4. Vocalis
5. Cricothyroid
34
What is function of post. cricoarytenoid?
open rima + abduct VF to give space for air to come out
35
What is function of transverse cricoarytenoid?
close VF
36
What is function of lat. cricoarytenoid?
close rima
37
What is function of oblique interarytenoid?
close VF
38
What is nerve supply to intrinsic muscles?
vagus
39
Where is sup. laryngeal nerve from + its function?
- vagus
| - supply mucous mem + sensory area of larynx above VF
40
Describe motor supply to larynx
- All intrinsic muscles supplied by laryngeal branches of vagus nerve.
- external branches supplies cricothyroid + remainder supplied by recurrent laryngeal nerve
41
Describe sensory supply to larynx
- vagus nerve sensory to larynx.
- internal laryngeal nerve supplies mucous membrane above vocal fold
- recurrent laryngeal nerve supplies below vocal fold.
42
Describe blood supply to larynx
- larynx receives its blood supply from sup. + inf. thyroid arteries.
- sup. gives off an int. laryngeal branch while the inf. gives off an inf. laryngeal branch which accompanies recurrent laryngeal nerve into larynx.
43
Describe venous drainage of larynx
- laryngeal veins drain into the superior and inferior thyroid veins
- sep in upper + lower pharynx
44
Describe lymphatic drainage of larynx
- submucosal lymphatic plexus of larynx drained by 2 sets of vessels.
- Above vocal folds they pierce thyrohyoid membrane to
reach upper deep cervical lymph nodes while below they join lower deep cervical lymph nodes
45
When does phonation normally take place?
- during expiration.
| - possible during inspiration but not efficient +,cannot be maintained for long.
46
What is breathing rate?
- 15 cycles per min with the time almost equally
divided between insp+ exp.
- During speech, rhythm is altered with insp occurring rapidly.
47
What is phonation?
- consists of converting an even flow of expired air passing through larynx into an oscillating flow with a freq of 16-20,000 Hz which is within range of human hearing.
48
How is phonation achieved?
- vocal folds adducted obstructing air flow.
- P then builds up from below until it forces folds apart allowing the air to escape.
- cycle repeated + converts the air into series of puffs at freq determined by sub-glottal P + mass + tension vocal ligs.
- freq of oscillating air also determines pitch which varies to allow intonation + expression.
49
What is articulation produced by?
the tongue and lips
50
How are vowel sounds formed?
by a continuous flow of air through the oral cavity the shape of which is modified by the muscles of the tongue and lips.
51
How are consonant sounds formed?
- constrictions of the vocal tract.
1. Labial - contact between the lips – BPM
2. Labiodentals - Lower lips & Upper incisors – FV
3. Lingopalatal - a) tip of tongue and anterior part of hard palate – DTR
b) dorsum of tongue + post. part of hard palate – JL
c) Dorsum of tongue + soft palate – K
52
How are sibilants formed?
S, SH, & Z air passes through narrow space between tip of tongue and + hard palate.
53
How are M&N achieved?
expelling air through nose
54
What may make speech unintelligible?
cleft palate/short lingual frenulum
55
What can affect articulation?
Loss of teeth and denture but most people adapt
