A 3-month-old infant presents with bulging anterior fontanelle, setting-sun sign, irritability, and increasing head circumference crossing percentiles. Ultrasound shows dilated lateral ventricles. The infant was born at 28 weeks with a history of Grade III intraventricular hemorrhage. Which type of hydrocephalus is most likely?
- A Communicating hydrocephalus due to impaired CSF absorption at arachnoid granulations ✓
- B Obstructive (non-communicating) hydrocephalus due to aqueductal stenosis
- C Hydrocephalus ex vacuo due to periventricular leukomalacia
- D Dandy-Walker malformation causing obstruction at foramen of Magendie
Explanation
Post-hemorrhagic hydrocephalus following IVH in preterm infants is characteristically communicating (non-obstructive) hydrocephalus. Blood products in the subarachnoid space cause inflammatory scarring of arachnoid granulations, impairing CSF resorption. This is distinct from congenital aqueductal stenosis (the most common cause of non-communicating hydrocephalus in older children). Hydrocephalus ex vacuo results from brain tissue loss (PVL) and is characterized by normal head circumference and absence of raised ICP signs. Dandy-Walker malformation causes non-communicating hydrocephalus via fourth ventricular obstruction.
Reference: Ghai Essential Pediatrics, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.