Macrocephaly

Question 1

Causes of Macrocephaly

Answer 1

A. CNS normal

1. Familial big head
2. Haemoglobinopathy - Thalassaemia
3. Normal varient
4. Disproportionally large head compares to body (IUGR, Preterm bb)

B. Abnormal CNS
1. Increase brain substance - Megaencephaly
Neurofibromatosis (NF)
Mucopolysaccharidosis (MPS)
Achondroplasia
2. SOL (Subdural effusion, brain tumor)
3. Increase CSF (Hydrocephalus)
4. Sotos Syndrome

Question 2

Clinical examination of Macrocephaly

Answer 2

1. HEAD
   a. Inspection - for size and shape of head (preterm), surgical scar, dilated veins/ sunset eye/ squint (Hydrocephalus) and cataract (MPS)
   b. Measure head circumference
   c. Palpate for fontanelle size and tension, suture separation and V-P shunt
   d. Translumination - >2.5cm diameter is significant (Unilateral - Subdural effusion; Posterior - Dandy Walker)
2. SPINE -Look for evidence of Spinal Bifida
3. Neurological exam and mentality esp for ataxia diplegia
4. Facial examination for Dysmorphic features, skin for rash and neurocutaneous sign (NF)
5. Eyes - Vision
6. Abdo - Scar, Organomegaly and Umbilical hernia (MPS)
7. Measure parent’s head circumference

N.B. If big head with no Shunt - think NF and look for Cafe au lait spots!