Pediatric Radiology
Core concepts
Understand age-specific imaging: ultrasound first in children (avoid radiation), ALARA principles, and the role of MRI. Know neonatal brain patterns: hypoxic-ischaemic encephalopathy (HIE), intraventricular haemorrhage grading, and the evolving appearance of the brain. Learn pediatric chest (foreign body, bronchiolitis, pneumonia patterns) and abdominal emergencies: intussusception (target sign), pyloric stenosis (thickened pylorus), malrotation (volvulus), and appendicitis. Know skeletal conditions: non-accidental injury (fracture patterns), developmental dysplasia of the hip, and bone tumours by age.
Traps
- Intussusception may reduce with air enema-do not rush to surgery if stable.
- Pyloric stenosis shows a thickened pyloric muscle on ultrasound-measure it.
- Malrotation with volvulus is a surgical emergency-upper GI contrast is diagnostic.
- Non-accidental injury patterns (metaphyseal corner fractures, rib fractures) must be recognised.
- Do not over-irradiate-use ultrasound and MRI where possible.
Worked example / rule of thumb
A 3-month-old with projectile vomiting: ultrasound shows pyloric muscle thickness >3 mm and canal length >14 mm-pyloric stenosis. Rule of thumb: ultrasound first in children; CT only when necessary. For a vomiting infant, consider pyloric stenosis, malrotation, and intussusception in the differential.
Key points
- Ultrasound first; ALARA in children.
- HIE and IVH grading in neonates.
- Intussusception: target sign, air enema reduction.
- Pyloric stenosis: measure muscle thickness.
- Recognise non-accidental injury patterns.