MIcrocephaly & Macrocephaly

Question 1

What is the definition of Microcephaly

Answer 1

An occipital-frontal circumference <2nd centile.

Question 2

What are some causes of microcephaly?

Answer 2

• Normal variation e.g. small child with small head
• Familial e.g. parents with small head
• Congenital infection
• Perinatal brain injury e.g. hypoxic ischaemic encephalopathy
• Fetal alcohol syndrome
• Syndromes: Patau
• Craniosynostosis

Question 3

What are some causes of macrocephaly?

Answer 3

• Normal variant
• Chronic hydrocephalus
• Chronic subdural effusion
• Neurofibromatosis
• Gigantism (e.g. Soto’s syndrome)
• Metabolic storage diseases
• Bone problems e.g. thalassaemia