A 6-week-old infant presents with macrocephaly, bulging anterior fontanelle, and 'setting sun sign'. Head circumference has crossed 2 centile lines upward in 2 weeks. CT brain shows dilated lateral ventricles with cortical mantle preserved. The communicating hydrocephalus in this neonate most likely results from:
- A Aqueduct of Sylvius stenosis causing obstructive hydrocephalus
- B Dandy-Walker malformation obstructing foramina of Luschka and Magendie
- C Post-haemorrhagic hydrocephalus following germinal matrix intraventricular haemorrhage ✓
- D Chiari type II malformation with foramen magnum obstruction
Correct answer: C. Post-haemorrhagic hydrocephalus following germinal matrix intraventricular haemorrhage
Explanation
Post-haemorrhagic hydrocephalus (PHH) following germinal matrix-intraventricular haemorrhage (GMH-IVH) is the most common cause of communicating hydrocephalus in preterm neonates presenting at 4–8 weeks of age. Blood in the subarachnoid space obstructs arachnoid granulations and impairs CSF resorption, producing communicating (non-obstructive) hydrocephalus with dilated all ventricles and preserved cortical mantle. Aqueductal stenosis causes non-communicating obstructive hydrocephalus. Dandy-Walker and Chiari II are structural malformations.
Reference: Ghai Essential Pediatrics, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.