The Child's Skull

Question 1

Neurocranium vs viscerocranium

Answer 1

Neurocranium: encases the brain
Viscerocranium: encases the face

Question 2

The brain doubles in size by _ months, and doubles again by __ months of age

Answer 2

• First double at 6 months
• Second double at 24 months

(Notice diminishing returns on speed)

Question 3

Where are the fontanelles located in a child’s skull? What are they? By what age do they close?

Answer 3

• Fontanelles are syndesmoses (connective tissue joints) between skull bones; allow brain to grow
• There are anterior, posterior, antero/posterolateral fontanelles
• Typically close by end of second year

Question 4

Why is craniosynostosis harmful in childrens’ development?

Answer 4

Premature fusion of skull bones means brain cannot expand as easily -> increased pressure -> harm

Question 5

What causes a cleft palate?

Answer 5

• Incomplete closure of maxillary processes during development
• Causes incomplete separation of nasal/oral cavities

Question 6

Describe differences in the proportion of adult vs baby’s skull

Answer 6

• Children have much larger cranium vs face
• In adulthood, the midface and mandible become more prominent

(Children also have much bigger heads relative to their body size; can cause increased heat loss etc)

Question 7

Adult vs child pharyngotympanic tube? How can a swollen adenoid/pharyngeal tonsil affect this?

Answer 7

• Children’s is shorter (easier for bacteria to get in from nasopharynx)
• Swollen adenoid can block outlet of eustachian tube; this leads to impaired drainage/pressure buildup (stasis is basis for infection)

Question 8

Location of vocal cords in children vs adults (link to story)

Answer 8

• In children, epiglottis and vocal cords are much higher

(This is why, when I was little and sick, Mum could see my epiglottis and god worried there was something in there)

Question 9

Why do kids mostly breathe through their noses?

Answer 9

• Because their tongues are proportionally larger
• Harder to get air through oral cavity; better to use nose

Question 10

Larynx + adenoids in kids vs adults?

Answer 10

• In kids, larynx is more superior (why?) and smaller (funnel shaped, so cricoid cartilage is narrowest part)
• Adenoids are proportionally larger (increased risk of ???)

Question 11

Why can it be dangerous to have a kid sleeping with a flexed neck?

Answer 11

• Short neck, longer/thinner/higher epiglottis
• Means that, with enough neck flexion, it can be hard for kids’ airways to remain open in this position

Question 12

How can babies suck and breathe at the same time?

Answer 12

• Higher larynx
• Lets larynx open directly into nasopharynx, bypassing oropharynx so both can occur at once

Question 13

Recall the four phases of swallowing

Answer 13

1. Oral (chewing, salivation, bolus formation)
2. Transit (tongue pushes bolus to pharynx
   (these two are voluntary)
3. Pharyngeal phase (reflexive soft palate elevation, pharyngeal constriction, opening of UES)
4. Oesophageal phase (reflexive peristalsis)