Voice across the lifespan

Question 1

When does embryonic development of the VFs occur?

Answer 1

• 1st evidence at 4th week
• Major structures of the larynx formed by 10-11th week
• VF complete by 12th week

Question 2

VF features in neonates and young children

Answer 2

• Thinner VF mucosa
• Greater proportion of collagen in VF muscle
• Layered structure not differentiated
• Immature vocal ligament develops by 4y and muscle fibres become stronger
• Vocal ligament matures by puberty

Question 3

Features of infant vocalisation (3)

Answer 3

• f0 high, small size/mass
• Vocalisations loud due to high f0 and children using greater lung pressure
• Increase in neuromuscular control allows intonational inflections to begin as early as 2weeks
• Initially an uncontrolled reflex
• Express pain/pleasure/hunger
• Lengthening and widening with growth
• Difficulty controlling tension and air pressure
• VF ECM begins to differentiate 2-5m

Question 4

Features of larynx in neonates

Answer 4

• Cartilage esp epiglottis very soft and pliable at birth
• Epiglottis & aryepiglottic folds tend to collapse inwards on inspiration if baby is in supine position
• Each of these factors predispose neonate to laryngeal stridor on inspiration (& occasional aspiration during feeding)
• Larynx high between C1-C3
• Descends to C6-C7 at puberty

Question 5

Laryngeal conditions associated with infant development (2)

Answer 5

1. Laryngomalacia
2. Vocal fold paralysis

Question 6

Features of laryngomalacia infancy

Answer 6

• Immature development of laryngeal cartilages
• ‘Floppy’ cartilage, narrow/curled epiglottis, aryepiglottic folds closely approximated
• Soft tissue collapses into larynx on inspiration
• Inspiratory stridor at birth/1st few weeks
• Usually resolves in 1st year

Question 7

Features of vocal fold paralysis in infancy

Answer 7

• Usually detected soon after birth by absent/weak cry, stridor, dyspnoea, aspiration
• Occasionally not detected until early childhood – breathy, soft, rough & monotone voice
• Aetiologies – idiopathic, birth trauma, cardiac surgery, CNS damage

Question 8

Laryngeal changes with puberty

Answer 8

• Rapid growth of larynx and vocal tract
• Usually begins at ~12-14 years in males & 13-15 years in females; complete by 14-15 years (most take 3-6 months, some up to 12 months)
• 5 VF layers fully developed

Question 9

Anatomic/physiological changes to ageing voice

Answer 9

• Reduced intrisinc musc innervation
• Diminished laryngeal neuromotor control
• VF atrophy/thinning of elastic fibres, incomplete closure
• Broken elastin replaced by collagen
• VF bowing males and oedema females
• Ossification/calcification of cartilages
• Mucous gland degeneration
• Diminished elastic recoil and vital capacity of lungs
• Decreased hyaluronic acid

Question 10

Perceptual features of ageing voice

Answer 10

• Breathy, rough, strained, instability
• Reduced loudness
• Pitch/voice breaks
• Reduced f0 range
• Increased pitch in men, down in women
• Vocal fatigue
• Increased shimmer and noise-to-harmonics ratio